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-rw-r--r--erts/emulator/nifs/common/prim_buffer_nif.c512
-rw-r--r--erts/emulator/nifs/common/prim_file_nif.c1298
-rw-r--r--erts/emulator/nifs/common/prim_file_nif.h243
-rw-r--r--erts/emulator/nifs/unix/unix_prim_file.c947
-rw-r--r--erts/emulator/nifs/win32/win_prim_file.c1526
5 files changed, 4526 insertions, 0 deletions
diff --git a/erts/emulator/nifs/common/prim_buffer_nif.c b/erts/emulator/nifs/common/prim_buffer_nif.c
new file mode 100644
index 0000000000..a8ef5fc355
--- /dev/null
+++ b/erts/emulator/nifs/common/prim_buffer_nif.c
@@ -0,0 +1,512 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#define STATIC_ERLANG_NIF 1
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#ifdef VALGRIND
+# include <valgrind/memcheck.h>
+#endif
+
+#define ACCUMULATOR_SIZE (2 << 10)
+
+#define FIND_NIF_RESCHEDULE_SIZE (1 << 20)
+
+/* NIF interface declarations */
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info);
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info);
+static void unload(ErlNifEnv *env, void* priv_data);
+
+static ErlNifResourceType *rtype_buffer;
+
+static ERL_NIF_TERM am_ok;
+static ERL_NIF_TERM am_error;
+
+static ERL_NIF_TERM am_lock_order_violation;
+
+static ERL_NIF_TERM am_acquired;
+static ERL_NIF_TERM am_busy;
+
+static ERL_NIF_TERM am_continue;
+
+static ERL_NIF_TERM am_out_of_memory;
+static ERL_NIF_TERM am_not_found;
+
+typedef struct {
+#ifdef DEBUG
+ erts_atomic32_t concurrent_users;
+#endif
+
+ ErlNifBinary accumulator;
+ size_t accumulated_bytes;
+ int accumulator_present;
+
+ ErlNifIOQueue *queue;
+
+ erts_atomic32_t external_lock;
+} buffer_data_t;
+
+static ERL_NIF_TERM new_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM peek_head_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM skip_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM size_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM write_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM copying_read_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM find_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM trylock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM unlock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ErlNifFunc nif_funcs[] = {
+ {"new", 0, new_nif},
+ {"size", 1, size_nif},
+ {"peek_head", 1, peek_head_nif},
+ {"copying_read", 2, copying_read_nif},
+ {"write", 2, write_nif},
+ {"skip", 2, skip_nif},
+ {"find_byte_index", 2, find_nif},
+ {"try_lock", 1, trylock_nif},
+ {"unlock", 1, unlock_nif},
+};
+
+ERL_NIF_INIT(prim_buffer, nif_funcs, load, NULL, upgrade, unload)
+
+static void gc_buffer(ErlNifEnv *env, void* data);
+
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info)
+{
+ am_ok = enif_make_atom(env, "ok");
+ am_error = enif_make_atom(env, "error");
+
+ am_lock_order_violation = enif_make_atom(env, "lock_order_violation");
+ am_acquired = enif_make_atom(env, "acquired");
+ am_busy = enif_make_atom(env, "busy");
+
+ am_continue = enif_make_atom(env, "continue");
+
+ am_out_of_memory = enif_make_atom(env, "out_of_memory");
+ am_not_found = enif_make_atom(env, "not_found");
+
+ rtype_buffer = enif_open_resource_type(env, NULL, "gc_buffer", gc_buffer,
+ ERL_NIF_RT_CREATE, NULL);
+
+ *priv_data = NULL;
+
+ return 0;
+}
+
+static void unload(ErlNifEnv *env, void* priv_data)
+{
+
+}
+
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info)
+{
+ if(*old_priv_data != NULL) {
+ return -1; /* Don't know how to do that */
+ }
+
+ if(*priv_data != NULL) {
+ return -1; /* Don't know how to do that */
+ }
+
+ if(load(env, priv_data, load_info)) {
+ return -1;
+ }
+
+ return 0;
+}
+
+static void gc_buffer(ErlNifEnv *env, void* data) {
+ buffer_data_t *buffer = (buffer_data_t*)data;
+
+ if(buffer->accumulator_present) {
+ enif_release_binary(&buffer->accumulator);
+ }
+
+ enif_ioq_destroy(buffer->queue);
+}
+
+static int get_buffer_data(ErlNifEnv *env, ERL_NIF_TERM opaque, buffer_data_t **buffer) {
+ return enif_get_resource(env, opaque, rtype_buffer, (void **)buffer);
+}
+
+/* Copies a number of bytes from the head of the iovec, skipping "vec_skip"
+ * vector elements followed by "byte_skip" bytes on the target vector. */
+static void copy_from_iovec(SysIOVec *iovec, int vec_len, int vec_skip,
+ size_t byte_skip, size_t size, char *data) {
+
+ size_t bytes_copied, skip_offset;
+ int vec_index;
+
+ skip_offset = byte_skip;
+ vec_index = vec_skip;
+ bytes_copied = 0;
+
+ while(bytes_copied < size) {
+ size_t block_size, copy_size;
+ char *block_start;
+
+ ASSERT(vec_index < vec_len);
+
+ block_start = (char*)iovec[vec_index].iov_base;
+ block_size = iovec[vec_index].iov_len;
+
+ copy_size = MIN(size - bytes_copied, block_size - skip_offset);
+ sys_memcpy(&data[bytes_copied], &block_start[skip_offset], copy_size);
+
+ bytes_copied += copy_size;
+ skip_offset = 0;
+
+ vec_index++;
+ }
+}
+
+/* Convenience function for copy_from_iovec over queues. */
+static void copy_from_queue(ErlNifIOQueue *queue, int queue_skip,
+ size_t byte_skip, size_t size, char *data) {
+
+ SysIOVec *queued_data;
+ int queue_length;
+
+ queued_data = enif_ioq_peek(queue, &queue_length);
+ ASSERT(queue_skip < queue_length);
+
+ copy_from_iovec(queued_data, queue_length, queue_skip, byte_skip, size, data);
+}
+
+static int enqueue_write_accumulator(buffer_data_t *buffer) {
+ ASSERT(!buffer->accumulator_present ^ (buffer->accumulated_bytes > 0));
+
+ if(buffer->accumulator_present && buffer->accumulated_bytes > 0) {
+ if(!enif_realloc_binary(&buffer->accumulator, buffer->accumulated_bytes)) {
+ return 0;
+ } else if(!enif_ioq_enq_binary(buffer->queue, &buffer->accumulator, 0)) {
+ return 0;
+ }
+
+ /* The queue owns the accumulator now. */
+ buffer->accumulator_present = 0;
+ buffer->accumulated_bytes = 0;
+ }
+
+ return 1;
+}
+
+static int combine_small_writes(buffer_data_t *buffer, ErlNifIOVec *iovec) {
+ ASSERT(!buffer->accumulator_present ^ (buffer->accumulated_bytes > 0));
+
+ if(buffer->accumulated_bytes + iovec->size >= ACCUMULATOR_SIZE) {
+ if(iovec->size >= (ACCUMULATOR_SIZE / 2)) {
+ return 0;
+ }
+
+ if(!enqueue_write_accumulator(buffer)) {
+ return 0;
+ }
+ }
+
+ if(!buffer->accumulator_present) {
+ if(!enif_alloc_binary(ACCUMULATOR_SIZE, &buffer->accumulator)) {
+ return 0;
+ }
+
+ buffer->accumulator_present = 1;
+ }
+
+ copy_from_iovec(iovec->iov, iovec->iovcnt, 0, 0, iovec->size,
+ (char*)&buffer->accumulator.data[buffer->accumulated_bytes]);
+ buffer->accumulated_bytes += iovec->size;
+
+ return 1;
+}
+
+/* *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** */
+
+static ERL_NIF_TERM new_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+ ERL_NIF_TERM result;
+
+ buffer = (buffer_data_t*)enif_alloc_resource(rtype_buffer, sizeof(buffer_data_t));
+ buffer->queue = enif_ioq_create(ERL_NIF_IOQ_NORMAL);
+
+ if(buffer->queue != NULL) {
+#ifdef DEBUG
+ erts_atomic32_init_nob(&buffer->concurrent_users, 0);
+#endif
+ erts_atomic32_init_nob(&buffer->external_lock, 0);
+
+ buffer->accumulator_present = 0;
+ buffer->accumulated_bytes = 0;
+
+ result = enif_make_resource(env, buffer);
+ } else {
+ result = enif_raise_exception(env, am_out_of_memory);
+ }
+
+ enif_release_resource(buffer);
+
+ return result;
+}
+
+static ERL_NIF_TERM size_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ size_t total_size;
+
+ if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+ total_size = enif_ioq_size(buffer->queue);
+
+ if(buffer->accumulator_present) {
+ total_size += buffer->accumulated_bytes;
+ } else {
+ ASSERT(buffer->accumulated_bytes == 0);
+ }
+
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ return enif_make_uint64(env, total_size);
+}
+
+static ERL_NIF_TERM copying_read_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ ERL_NIF_TERM result;
+ unsigned char *data;
+ Uint64 block_size;
+
+ if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+ || !enif_get_uint64(env, argv[1], &block_size)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+ if(!enqueue_write_accumulator(buffer)) {
+ return enif_raise_exception(env, am_out_of_memory);
+ }
+
+ if(enif_ioq_size(buffer->queue) < block_size) {
+ return enif_make_badarg(env);
+ }
+
+ data = enif_make_new_binary(env, block_size, &result);
+
+ if(block_size > 0) {
+ copy_from_queue(buffer->queue, 0, 0, block_size, (char*)data);
+ enif_ioq_deq(buffer->queue, block_size, NULL);
+ }
+
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ return result;
+}
+
+static ERL_NIF_TERM write_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ ErlNifIOVec vec, *iovec = &vec;
+ ERL_NIF_TERM tail;
+
+ if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+ || !enif_inspect_iovec(env, 64, argv[1], &tail, &iovec)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+ if(!combine_small_writes(buffer, iovec)) {
+ if(!enqueue_write_accumulator(buffer) || !enif_ioq_enqv(buffer->queue, iovec, 0)) {
+ return enif_raise_exception(env, am_out_of_memory);
+ }
+ }
+
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ if(!enif_is_empty_list(env, tail)) {
+ const ERL_NIF_TERM new_argv[2] = {argv[0], tail};
+
+ return enif_schedule_nif(env, "write", 0, &write_nif, argc, new_argv);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM peek_head_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ ERL_NIF_TERM result;
+
+ if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+ if(!enqueue_write_accumulator(buffer)) {
+ return enif_raise_exception(env, am_out_of_memory);
+ }
+
+ if(!enif_ioq_peek_head(env, buffer->queue, NULL, &result)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ return result;
+}
+
+static ERL_NIF_TERM skip_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ Uint64 block_size;
+
+ if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+ || !enif_get_uint64(env, argv[1], &block_size)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+ if(!enqueue_write_accumulator(buffer)) {
+ return enif_raise_exception(env, am_out_of_memory);
+ } else if(enif_ioq_size(buffer->queue) < block_size) {
+ return enif_make_badarg(env);
+ }
+
+ enif_ioq_deq(buffer->queue, block_size, NULL);
+
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM find_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ int queue_length, queue_index;
+ SysIOVec *queued_data;
+ size_t queue_size;
+
+ size_t search_offset;
+ int needle;
+
+ if(argc != 2 || !get_buffer_data(env, argv[0], &buffer)
+ || !enif_get_int(env, argv[1], &needle)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_inc_read_acqb(&buffer->concurrent_users) == 1);
+
+ if(!enqueue_write_accumulator(buffer)) {
+ return enif_raise_exception(env, am_out_of_memory);
+ } else if(needle < 0 || needle > 255) {
+ return enif_make_badarg(env);
+ }
+
+ queued_data = enif_ioq_peek(buffer->queue, &queue_length);
+ queue_size = enif_ioq_size(buffer->queue);
+ queue_index = 0;
+
+ search_offset = 0;
+
+ if(queue_size > (FIND_NIF_RESCHEDULE_SIZE / 100)) {
+ if(enif_thread_type() == ERL_NIF_THR_NORMAL_SCHEDULER) {
+ int timeslice_percent;
+
+ if(queue_size >= FIND_NIF_RESCHEDULE_SIZE) {
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ return enif_schedule_nif(env, "find",
+ ERL_NIF_DIRTY_JOB_CPU_BOUND, &find_nif, argc, argv);
+ }
+
+ timeslice_percent = (queue_size * 100) / FIND_NIF_RESCHEDULE_SIZE;
+ enif_consume_timeslice(env, timeslice_percent);
+ }
+ }
+
+ while(queue_index < queue_length) {
+ char *needle_address;
+ char *block_start;
+ size_t block_size;
+
+ block_start = queued_data[queue_index].iov_base;
+ block_size = queued_data[queue_index].iov_len;
+
+ needle_address = memchr(block_start, needle, block_size);
+
+ if(needle_address != NULL) {
+ size_t result = search_offset + (needle_address - block_start);
+
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ return enif_make_tuple2(env, am_ok, enif_make_uint64(env, result));
+ }
+
+ search_offset += block_size;
+ queue_index++;
+ }
+
+ ASSERT(erts_atomic32_dec_read_relb(&buffer->concurrent_users) == 0);
+
+ return am_not_found;
+}
+
+/* */
+
+static ERL_NIF_TERM trylock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+ return enif_make_badarg(env);
+ }
+
+ if(erts_atomic32_cmpxchg_acqb(&buffer->external_lock, 1, 0) == 0) {
+ return am_acquired;
+ }
+
+ return am_busy;
+}
+
+static ERL_NIF_TERM unlock_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ buffer_data_t *buffer;
+
+ if(argc != 1 || !get_buffer_data(env, argv[0], &buffer)) {
+ return enif_make_badarg(env);
+ }
+
+ if(erts_atomic32_cmpxchg_relb(&buffer->external_lock, 0, 1) == 0) {
+ return enif_raise_exception(env, am_lock_order_violation);
+ }
+
+ return am_ok;
+}
diff --git a/erts/emulator/nifs/common/prim_file_nif.c b/erts/emulator/nifs/common/prim_file_nif.c
new file mode 100644
index 0000000000..a78ee62677
--- /dev/null
+++ b/erts/emulator/nifs/common/prim_file_nif.c
@@ -0,0 +1,1298 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017-2018. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#define STATIC_ERLANG_NIF 1
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#ifdef VALGRIND
+# include <valgrind/memcheck.h>
+#endif
+
+#include "erl_driver.h"
+#include "prim_file_nif.h"
+
+/* NIF interface declarations */
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM load_info);
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info);
+static void unload(ErlNifEnv *env, void* priv_data);
+
+static ErlNifResourceType *efile_resource_type;
+
+static ERL_NIF_TERM am_close;
+
+static ERL_NIF_TERM am_ok;
+static ERL_NIF_TERM am_error;
+static ERL_NIF_TERM am_continue;
+
+static ERL_NIF_TERM am_file_info;
+
+/* File modes */
+static ERL_NIF_TERM am_read;
+static ERL_NIF_TERM am_write;
+static ERL_NIF_TERM am_exclusive;
+static ERL_NIF_TERM am_append;
+static ERL_NIF_TERM am_sync;
+static ERL_NIF_TERM am_skip_type_check;
+
+/* enum efile_access_t; read and write are defined above.*/
+static ERL_NIF_TERM am_read_write;
+static ERL_NIF_TERM am_none;
+
+/* enum efile_advise_t */
+static ERL_NIF_TERM am_normal;
+static ERL_NIF_TERM am_random;
+static ERL_NIF_TERM am_sequential;
+static ERL_NIF_TERM am_will_need;
+static ERL_NIF_TERM am_dont_need;
+static ERL_NIF_TERM am_no_reuse;
+
+/* enum efile_filetype_t */
+static ERL_NIF_TERM am_device;
+static ERL_NIF_TERM am_directory;
+static ERL_NIF_TERM am_regular;
+static ERL_NIF_TERM am_symlink;
+static ERL_NIF_TERM am_other;
+
+/* enum efile_seek_t, 'eof' marker. */
+static ERL_NIF_TERM am_bof;
+static ERL_NIF_TERM am_cur;
+static ERL_NIF_TERM am_eof;
+
+static ERL_NIF_TERM read_info_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_permissions_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_owner_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_time_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM read_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM list_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM make_hard_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM make_soft_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM rename_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM make_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM del_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM del_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM get_device_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM get_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM set_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM read_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+static ERL_NIF_TERM open_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM close_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+/* Internal ops */
+static ERL_NIF_TERM delayed_close_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM get_handle_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM altname_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]);
+
+/* All file handle operations are passed through a wrapper that handles state
+ * transitions, marking it as busy during the course of the operation, and
+ * closing on completion if the owner died in the middle of an operation.
+ *
+ * This is pretty ugly but required as there's no way to tell when it's safe to
+ * asynchronously close a file; the event could have fired just before landing
+ * in a system call which will fail with EBADF at best or alias a newly opened
+ * fd at worst.
+ *
+ * The old driver got away with enqueueing the close operation on the same
+ * async queue as all of its other operations, but since dirty schedulers use a
+ * single global queue there's no natural way to schedule an asynchronous close
+ * "behind" other operations.
+ *
+ * The states may transition as follows:
+ *
+ * IDLE ->
+ * BUSY (file_handle_wrapper) |
+ * CLOSED (owner_death_callback)
+ *
+ * BUSY ->
+ * IDLE (file_handle_wrapper)
+ * CLOSED (close_nif_impl)
+ * CLOSE_PENDING (owner_death_callback)
+ *
+ * CLOSE_PENDING ->
+ * CLOSED (file_handle_wrapper)
+ *
+ * Should the owner of a file die, we can't close it immediately as that could
+ * potentially block a normal scheduler. When entering the CLOSED state from
+ * owner_death_callback, we will instead send a message to the erts_prim_file
+ * process that will then close the file through delayed_close_nif. */
+
+typedef ERL_NIF_TERM (*file_op_impl_t)(efile_data_t *d, ErlNifEnv *env,
+ int argc, const ERL_NIF_TERM argv[]);
+static ERL_NIF_TERM file_handle_wrapper(file_op_impl_t operation, ErlNifEnv *env,
+ int argc, const ERL_NIF_TERM argv[]);
+
+#define WRAP_FILE_HANDLE_EXPORT(name) \
+ static ERL_NIF_TERM name ## _impl (efile_data_t *d, ErlNifEnv *env, \
+ int argc, const ERL_NIF_TERM argv[]);\
+ static ERL_NIF_TERM name(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) { \
+ return file_handle_wrapper( name ## _impl , env, argc, argv); \
+ }
+
+WRAP_FILE_HANDLE_EXPORT(read_nif)
+WRAP_FILE_HANDLE_EXPORT(write_nif)
+WRAP_FILE_HANDLE_EXPORT(pread_nif)
+WRAP_FILE_HANDLE_EXPORT(pwrite_nif)
+WRAP_FILE_HANDLE_EXPORT(seek_nif)
+WRAP_FILE_HANDLE_EXPORT(sync_nif)
+WRAP_FILE_HANDLE_EXPORT(truncate_nif)
+WRAP_FILE_HANDLE_EXPORT(allocate_nif)
+WRAP_FILE_HANDLE_EXPORT(advise_nif)
+WRAP_FILE_HANDLE_EXPORT(get_handle_nif)
+WRAP_FILE_HANDLE_EXPORT(ipread_s32bu_p32bu_nif)
+
+static ErlNifFunc nif_funcs[] = {
+ /* File handle ops */
+ {"open_nif", 2, open_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"close_nif", 1, close_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"read_nif", 2, read_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"write_nif", 2, write_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"pread_nif", 3, pread_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"pwrite_nif", 3, pwrite_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"seek_nif", 3, seek_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"sync_nif", 2, sync_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"truncate_nif", 1, truncate_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"allocate_nif", 3, allocate_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"advise_nif", 4, advise_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+
+ /* Filesystem ops */
+ {"make_hard_link_nif", 2, make_hard_link_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"make_soft_link_nif", 2, make_soft_link_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"rename_nif", 2, rename_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"read_info_nif", 2, read_info_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"set_permissions_nif", 2, set_permissions_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"set_owner_nif", 3, set_owner_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"set_time_nif", 4, set_time_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"read_link_nif", 1, read_link_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"list_dir_nif", 1, list_dir_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"make_dir_nif", 1, make_dir_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"del_file_nif", 1, del_file_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"del_dir_nif", 1, del_dir_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"get_device_cwd_nif", 1, get_device_cwd_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"set_cwd_nif", 1, set_cwd_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"get_cwd_nif", 0, get_cwd_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+
+ /* These operations are equivalent to chained calls of other operations,
+ * but have been moved down to avoid excessive rescheduling. */
+ {"ipread_s32bu_p32bu_nif", 3, ipread_s32bu_p32bu_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"read_file_nif", 1, read_file_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+
+ /* Internal ops. */
+ {"get_handle_nif", 1, get_handle_nif},
+ {"delayed_close_nif", 1, delayed_close_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+ {"altname_nif", 1, altname_nif, ERL_NIF_DIRTY_JOB_IO_BOUND},
+};
+
+ERL_NIF_INIT(prim_file, nif_funcs, load, NULL, upgrade, unload)
+
+static ErlNifPid erts_prim_file_pid;
+
+static void owner_death_callback(ErlNifEnv* env, void* obj, ErlNifPid* pid, ErlNifMonitor* mon);
+
+static int load(ErlNifEnv *env, void** priv_data, ERL_NIF_TERM prim_file_pid)
+{
+ ErlNifResourceTypeInit callbacks;
+
+ if(!enif_get_local_pid(env, prim_file_pid, &erts_prim_file_pid)) {
+ ASSERT(!"bad pid passed to prim_file_nif");
+ }
+
+ am_close = enif_make_atom(env, "close");
+
+ am_ok = enif_make_atom(env, "ok");
+ am_error = enif_make_atom(env, "error");
+ am_continue = enif_make_atom(env, "continue");
+
+ am_read = enif_make_atom(env, "read");
+ am_write = enif_make_atom(env, "write");
+ am_exclusive = enif_make_atom(env, "exclusive");
+ am_append = enif_make_atom(env, "append");
+ am_sync = enif_make_atom(env, "sync");
+ am_skip_type_check = enif_make_atom(env, "skip_type_check");
+
+ am_read_write = enif_make_atom(env, "read_write");
+ am_none = enif_make_atom(env, "none");
+
+ am_normal = enif_make_atom(env, "normal");
+ am_random = enif_make_atom(env, "random");
+ am_sequential = enif_make_atom(env, "sequential");
+ am_will_need = enif_make_atom(env, "will_need");
+ am_dont_need = enif_make_atom(env, "dont_need");
+ am_no_reuse = enif_make_atom(env, "no_reuse");
+
+ am_device = enif_make_atom(env, "device");
+ am_directory = enif_make_atom(env, "directory");
+ am_regular = enif_make_atom(env, "regular");
+ am_symlink = enif_make_atom(env, "symlink");
+ am_other = enif_make_atom(env, "other");
+
+ am_file_info = enif_make_atom(env, "file_info");
+
+ am_bof = enif_make_atom(env, "bof");
+ am_cur = enif_make_atom(env, "cur");
+ am_eof = enif_make_atom(env, "eof");
+
+ callbacks.down = owner_death_callback;
+ callbacks.dtor = NULL;
+ callbacks.stop = NULL;
+
+ efile_resource_type = enif_open_resource_type_x(env, "efile", &callbacks,
+ ERL_NIF_RT_CREATE, NULL);
+
+ *priv_data = NULL;
+
+ return 0;
+}
+
+static void unload(ErlNifEnv *env, void* priv_data)
+{
+
+}
+
+static int upgrade(ErlNifEnv *env, void** priv_data, void** old_priv_data, ERL_NIF_TERM load_info)
+{
+ if(*old_priv_data != NULL) {
+ return -1; /* Don't know how to do that */
+ }
+ if(*priv_data != NULL) {
+ return -1; /* Don't know how to do that */
+ }
+ if(load(env, priv_data, load_info)) {
+ return -1;
+ }
+ return 0;
+}
+
+static ERL_NIF_TERM posix_error_to_tuple(ErlNifEnv *env, posix_errno_t posix_errno) {
+ ERL_NIF_TERM error = enif_make_atom(env, erl_errno_id(posix_errno));
+ return enif_make_tuple2(env, am_error, error);
+}
+
+static int get_file_data(ErlNifEnv *env, ERL_NIF_TERM opaque, efile_data_t **d) {
+ return enif_get_resource(env, opaque, efile_resource_type, (void **)d);
+}
+
+static ERL_NIF_TERM file_handle_wrapper(file_op_impl_t operation, ErlNifEnv *env,
+ int argc, const ERL_NIF_TERM argv[]) {
+
+ efile_data_t *d;
+
+ enum efile_state_t previous_state;
+ ERL_NIF_TERM result;
+
+ if(argc < 1 || !get_file_data(env, argv[0], &d)) {
+ return enif_make_badarg(env);
+ }
+
+ previous_state = erts_atomic32_cmpxchg_acqb(&d->state,
+ EFILE_STATE_BUSY, EFILE_STATE_IDLE);
+
+ if(previous_state == EFILE_STATE_IDLE) {
+ result = operation(d, env, argc - 1, &argv[1]);
+
+ previous_state = erts_atomic32_cmpxchg_relb(&d->state,
+ EFILE_STATE_IDLE, EFILE_STATE_BUSY);
+
+ ASSERT(previous_state != EFILE_STATE_IDLE);
+
+ if(previous_state == EFILE_STATE_CLOSE_PENDING) {
+ /* This is the only point where a change from CLOSE_PENDING is
+ * possible, and we're running synchronously, so we can't race with
+ * anything else here. */
+ posix_errno_t ignored;
+
+ erts_atomic32_set_acqb(&d->state, EFILE_STATE_CLOSED);
+ efile_close(d, &ignored);
+ }
+ } else {
+ /* CLOSE_PENDING should be impossible at this point since it requires
+ * a transition from BUSY; the only valid state here is CLOSED. */
+ ASSERT(previous_state == EFILE_STATE_CLOSED);
+
+ result = posix_error_to_tuple(env, EINVAL);
+ }
+
+ return result;
+}
+
+/* This is a special close operation used by the erts_prim_file process for
+ * cleaning up orphaned files. It differs from the ordinary close_nif in that
+ * it only works for files that have already entered the CLOSED state. */
+static ERL_NIF_TERM delayed_close_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t ignored;
+ efile_data_t *d;
+
+ ASSERT(argc == 1);
+ if(!get_file_data(env, argv[0], &d)) {
+ return enif_make_badarg(env);
+ }
+
+ ASSERT(erts_atomic32_read_acqb(&d->state) == EFILE_STATE_CLOSED);
+ efile_close(d, &ignored);
+
+ return am_ok;
+}
+
+static void owner_death_callback(ErlNifEnv* env, void* obj, ErlNifPid* pid, ErlNifMonitor* mon) {
+ efile_data_t *d = (efile_data_t*)obj;
+
+ (void)env;
+ (void)pid;
+ (void)mon;
+
+ for(;;) {
+ enum efile_state_t previous_state;
+
+ previous_state = erts_atomic32_cmpxchg_acqb(&d->state,
+ EFILE_STATE_CLOSED, EFILE_STATE_IDLE);
+
+ switch(previous_state) {
+ case EFILE_STATE_IDLE:
+ {
+ /* We cannot close the file here as that could block a normal
+ * scheduler, so we tell erts_prim_file to do it for us.
+ *
+ * This can in turn become a bottleneck (especially in cases
+ * like NFS failure), but it's less problematic than blocking
+ * thread progress. */
+ ERL_NIF_TERM message, file_ref;
+
+ file_ref = enif_make_resource(env, d);
+ message = enif_make_tuple2(env, am_close, file_ref);
+
+ if(!enif_send(env, &erts_prim_file_pid, NULL, message)) {
+ ERTS_INTERNAL_ERROR("Failed to defer prim_file close.");
+ }
+
+ return;
+ }
+ case EFILE_STATE_CLOSE_PENDING:
+ case EFILE_STATE_CLOSED:
+ /* We're either already closed or managed to mark ourselves for
+ * closure in the previous iteration. */
+ return;
+ case EFILE_STATE_BUSY:
+ /* Schedule ourselves to be closed once the current operation
+ * finishes, retrying the [IDLE -> CLOSED] transition in case we
+ * narrowly passed the [BUSY -> IDLE] one. */
+ erts_atomic32_cmpxchg_nob(&d->state,
+ EFILE_STATE_CLOSE_PENDING, EFILE_STATE_BUSY);
+ break;
+ }
+ }
+}
+
+static ERL_NIF_TERM efile_filetype_to_atom(enum efile_filetype_t type) {
+ switch(type) {
+ case EFILE_FILETYPE_DEVICE: return am_device;
+ case EFILE_FILETYPE_DIRECTORY: return am_directory;
+ case EFILE_FILETYPE_REGULAR: return am_regular;
+ case EFILE_FILETYPE_SYMLINK: return am_symlink;
+ case EFILE_FILETYPE_OTHER: return am_other;
+ }
+
+ return am_other;
+}
+
+static ERL_NIF_TERM efile_access_to_atom(enum efile_access_t type) {
+ if(type & EFILE_ACCESS_READ && !(type & EFILE_ACCESS_WRITE)) {
+ return am_read;
+ } else if(type & EFILE_ACCESS_WRITE && !(type & EFILE_ACCESS_READ)) {
+ return am_write;
+ } else if(type & EFILE_ACCESS_READ_WRITE) {
+ return am_read_write;
+ }
+
+ return am_none;
+}
+
+static enum efile_modes_t efile_translate_modelist(ErlNifEnv *env, ERL_NIF_TERM list) {
+ enum efile_modes_t modes;
+ ERL_NIF_TERM head, tail;
+
+ modes = 0;
+
+ while(enif_get_list_cell(env, list, &head, &tail)) {
+ if(enif_is_identical(head, am_read)) {
+ modes |= EFILE_MODE_READ;
+ } else if(enif_is_identical(head, am_write)) {
+ modes |= EFILE_MODE_WRITE;
+ } else if(enif_is_identical(head, am_exclusive)) {
+ modes |= EFILE_MODE_EXCLUSIVE;
+ } else if(enif_is_identical(head, am_append)) {
+ modes |= EFILE_MODE_APPEND;
+ } else if(enif_is_identical(head, am_sync)) {
+ modes |= EFILE_MODE_SYNC;
+ } else if(enif_is_identical(head, am_skip_type_check)) {
+ modes |= EFILE_MODE_SKIP_TYPE_CHECK;
+ } else {
+ /* Modes like 'raw', 'ram', 'delayed_writes' etc are handled
+ * further up the chain. */
+ }
+
+ list = tail;
+ }
+
+ if(modes & (EFILE_MODE_APPEND | EFILE_MODE_EXCLUSIVE)) {
+ /* 'append' and 'exclusive' are documented as "open for writing." */
+ modes |= EFILE_MODE_WRITE;
+ } else if(!(modes & EFILE_MODE_READ_WRITE)) {
+ /* Defaulting to read if !(W|R) is undocumented, but specifically
+ * tested against in file_SUITE. */
+ modes |= EFILE_MODE_READ;
+ }
+
+ return modes;
+}
+
+static ERL_NIF_TERM open_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+ efile_data_t *d;
+
+ ErlNifPid controlling_process;
+ enum efile_modes_t modes;
+ ERL_NIF_TERM result;
+ efile_path_t path;
+
+ if(argc != 2 || !enif_is_list(env, argv[1])) {
+ return enif_make_badarg(env);
+ }
+
+ modes = efile_translate_modelist(env, argv[1]);
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_open(&path, modes, efile_resource_type, &d))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ enif_self(env, &controlling_process);
+
+ if(enif_monitor_process(env, d, &controlling_process, &d->monitor)) {
+ /* We need to close the file manually as we haven't registered a
+ * destructor. */
+ posix_errno_t ignored;
+
+ erts_atomic32_set_acqb(&d->state, EFILE_STATE_CLOSED);
+ efile_close(d, &ignored);
+
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ /* Note that we do not call enif_release_resource at this point. While it's
+ * normally safe to leave resource management to the GC, efile_close is a
+ * blocking operation which must not be done in the GC callback, and we
+ * can't defer it as the resource is gone as soon as it returns.
+ *
+ * We instead keep the resource alive until efile_close is called, after
+ * which it's safe to leave things to the GC. If the controlling process
+ * were to die before the user had a chance to close their file, the above
+ * monitor will tell the erts_prim_file process to close it for them. */
+ result = enif_make_resource(env, d);
+
+ return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM close_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ enum efile_state_t previous_state;
+ efile_data_t *d;
+
+ ASSERT(argc == 1);
+ if(!get_file_data(env, argv[0], &d)) {
+ return enif_make_badarg(env);
+ }
+
+ previous_state = erts_atomic32_cmpxchg_acqb(&d->state,
+ EFILE_STATE_CLOSED, EFILE_STATE_IDLE);
+
+ if(previous_state == EFILE_STATE_IDLE) {
+ posix_errno_t error;
+
+ enif_demonitor_process(env, d, &d->monitor);
+
+ if(!efile_close(d, &error)) {
+ return posix_error_to_tuple(env, error);
+ }
+
+ return am_ok;
+ } else {
+ /* CLOSE_PENDING should be impossible at this point since it requires
+ * a transition from BUSY; the only valid state here is CLOSED. */
+ ASSERT(previous_state == EFILE_STATE_CLOSED);
+
+ return posix_error_to_tuple(env, EINVAL);
+ }
+}
+
+static ERL_NIF_TERM read_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ Sint64 bytes_read, block_size;
+ SysIOVec read_vec[1];
+ ErlNifBinary result;
+
+ if(argc != 1 || !enif_is_number(env, argv[0])) {
+ return enif_make_badarg(env);
+ }
+
+ if(!enif_get_int64(env, argv[0], &block_size) || block_size < 0) {
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ if(!enif_alloc_binary(block_size, &result)) {
+ return posix_error_to_tuple(env, ENOMEM);
+ }
+
+ read_vec[0].iov_base = result.data;
+ read_vec[0].iov_len = result.size;
+
+ bytes_read = efile_readv(d, read_vec, 1);
+ ASSERT(bytes_read <= block_size);
+
+ if(bytes_read < 0) {
+ enif_release_binary(&result);
+ return posix_error_to_tuple(env, d->posix_errno);
+ } else if(bytes_read == 0) {
+ enif_release_binary(&result);
+ return am_eof;
+ }
+
+ if(bytes_read < block_size && !enif_realloc_binary(&result, bytes_read)) {
+ ERTS_INTERNAL_ERROR("Failed to shrink read result.");
+ }
+
+ return enif_make_tuple2(env, am_ok, enif_make_binary(env, &result));
+}
+
+static ERL_NIF_TERM write_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ ErlNifIOVec vec, *input = &vec;
+ Sint64 bytes_written;
+ ERL_NIF_TERM tail;
+
+ if(argc != 1 || !enif_inspect_iovec(env, 64, argv[0], &tail, &input)) {
+ return enif_make_badarg(env);
+ }
+
+ bytes_written = efile_writev(d, input->iov, input->iovcnt);
+
+ if(bytes_written < 0) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ }
+
+ if(!enif_is_empty_list(env, tail)) {
+ ASSERT(bytes_written > 0);
+ return enif_make_tuple2(env, am_continue, tail);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM pread_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ Sint64 bytes_read, block_size, offset;
+ SysIOVec read_vec[1];
+ ErlNifBinary result;
+
+ if(argc != 2 || !enif_is_number(env, argv[0])
+ || !enif_is_number(env, argv[1])) {
+ return enif_make_badarg(env);
+ }
+
+ if(!enif_get_int64(env, argv[0], &offset) ||
+ !enif_get_int64(env, argv[1], &block_size) ||
+ (offset < 0 || block_size < 0)) {
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ if(!enif_alloc_binary(block_size, &result)) {
+ return posix_error_to_tuple(env, ENOMEM);
+ }
+
+ read_vec[0].iov_base = result.data;
+ read_vec[0].iov_len = result.size;
+
+ bytes_read = efile_preadv(d, offset, read_vec, 1);
+
+ if(bytes_read < 0) {
+ enif_release_binary(&result);
+ return posix_error_to_tuple(env, d->posix_errno);
+ } else if(bytes_read == 0) {
+ enif_release_binary(&result);
+ return am_eof;
+ }
+
+ if(bytes_read < block_size && !enif_realloc_binary(&result, bytes_read)) {
+ ERTS_INTERNAL_ERROR("Failed to shrink pread result.");
+ }
+
+ return enif_make_tuple2(env, am_ok, enif_make_binary(env, &result));
+}
+
+static ERL_NIF_TERM pwrite_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ ErlNifIOVec vec, *input = &vec;
+ Sint64 bytes_written, offset;
+ ERL_NIF_TERM tail;
+
+ if(argc != 2 || !enif_is_number(env, argv[0])
+ || !enif_inspect_iovec(env, 64, argv[1], &tail, &input)) {
+ return enif_make_badarg(env);
+ }
+
+ if(!enif_get_int64(env, argv[0], &offset) || offset < 0) {
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ bytes_written = efile_pwritev(d, offset, input->iov, input->iovcnt);
+
+ if(bytes_written < 0) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ }
+
+ if(!enif_is_empty_list(env, tail)) {
+ ASSERT(bytes_written > 0);
+ return enif_make_tuple3(env, am_continue,
+ enif_make_int64(env, bytes_written), tail);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM seek_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ Sint64 new_position, offset;
+ enum efile_seek_t seek;
+
+ if(argc != 2 || !enif_get_int64(env, argv[1], &offset)) {
+ return enif_make_badarg(env);
+ }
+
+ if(enif_is_identical(argv[0], am_bof)) {
+ seek = EFILE_SEEK_BOF;
+ } else if(enif_is_identical(argv[0], am_cur)) {
+ seek = EFILE_SEEK_CUR;
+ } else if(enif_is_identical(argv[0], am_eof)) {
+ seek = EFILE_SEEK_EOF;
+ } else {
+ return enif_make_badarg(env);
+ }
+
+ if(!efile_seek(d, seek, offset, &new_position)) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ }
+
+ return enif_make_tuple2(env, am_ok, enif_make_uint64(env, new_position));
+}
+
+static ERL_NIF_TERM sync_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ int data_only;
+
+ if(argc != 1 || !enif_get_int(env, argv[0], &data_only)) {
+ return enif_make_badarg(env);
+ }
+
+ if(!efile_sync(d, data_only)) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM truncate_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ if(argc != 0) {
+ return enif_make_badarg(env);
+ }
+
+ if(!efile_truncate(d)) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM allocate_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ Sint64 offset, length;
+
+ if(argc != 2 || !enif_is_number(env, argv[0])
+ || !enif_is_number(env, argv[1])) {
+ return enif_make_badarg(env);
+ }
+
+ if(!enif_get_int64(env, argv[0], &offset) ||
+ !enif_get_int64(env, argv[1], &length) ||
+ (offset < 0 || length < 0)) {
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ if(!efile_allocate(d, offset, length)) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM advise_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ enum efile_advise_t advise;
+ Sint64 offset, length;
+
+ if(argc != 3 || !enif_is_number(env, argv[0])
+ || !enif_is_number(env, argv[1])) {
+ return enif_make_badarg(env);
+ }
+
+ if(!enif_get_int64(env, argv[0], &offset) ||
+ !enif_get_int64(env, argv[1], &length) ||
+ (offset < 0 || length < 0)) {
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ if(enif_is_identical(argv[2], am_normal)) {
+ advise = EFILE_ADVISE_NORMAL;
+ } else if(enif_is_identical(argv[2], am_random)) {
+ advise = EFILE_ADVISE_RANDOM;
+ } else if(enif_is_identical(argv[2], am_sequential)) {
+ advise = EFILE_ADVISE_SEQUENTIAL;
+ } else if(enif_is_identical(argv[2], am_will_need)) {
+ advise = EFILE_ADVISE_WILL_NEED;
+ } else if(enif_is_identical(argv[2], am_dont_need)) {
+ advise = EFILE_ADVISE_DONT_NEED;
+ } else if(enif_is_identical(argv[2], am_no_reuse)) {
+ advise = EFILE_ADVISE_NO_REUSE;
+ } else {
+ /* The tests check for EINVAL instead of badarg. Sigh. */
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ if(!efile_advise(d, offset, length, advise)) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ }
+
+ return am_ok;
+}
+
+/* This undocumented function reads a pointer and then reads the data block
+ * described by said pointer. It was reverse-engineered from the old
+ * implementation so while all tests pass it may not be entirely correct. Our
+ * current understanding is as follows:
+ *
+ * Pointer layout:
+ *
+ * <<Size:1/integer-unit:32, Offset:1/integer-unit:32>>
+ *
+ * Where Offset is the -absolute- address to the data block.
+ *
+ * *) If we fail to read the pointer block in its entirety, we return eof.
+ * *) If the provided max_payload_size is larger than Size, we return eof.
+ * *) If we fail to read any data whatsoever at Offset, we return
+ * {ok, {Size, Offset, eof}}
+ * *) Otherwise, we return {ok, {Size, Offset, Data}}. Note that the size
+ * of Data may be smaller than Size if we encounter EOF before we could
+ * read the entire block.
+ *
+ * On errors we'll return {error, posix()} regardless of whether they
+ * happened before or after reading the pointer block. */
+static ERL_NIF_TERM ipread_s32bu_p32bu_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ Sint64 payload_offset, payload_size;
+
+ SysIOVec read_vec[1];
+ Sint64 bytes_read;
+
+ ErlNifBinary payload;
+
+ if(argc != 2 || !enif_is_number(env, argv[0])
+ || !enif_is_number(env, argv[1])) {
+ return enif_make_badarg(env);
+ }
+
+ {
+ Sint64 max_payload_size, pointer_offset;
+ unsigned char pointer_block[8];
+
+ if(!enif_get_int64(env, argv[0], &pointer_offset) ||
+ !enif_get_int64(env, argv[1], &max_payload_size) ||
+ (pointer_offset < 0 || max_payload_size >= 1u << 31)) {
+ return posix_error_to_tuple(env, EINVAL);
+ }
+
+ read_vec[0].iov_base = pointer_block;
+ read_vec[0].iov_len = sizeof(pointer_block);
+
+ bytes_read = efile_preadv(d, pointer_offset, read_vec, 1);
+
+ if(bytes_read < 0) {
+ return posix_error_to_tuple(env, d->posix_errno);
+ } else if(bytes_read < sizeof(pointer_block)) {
+ return am_eof;
+ }
+
+ payload_size = (Uint32)get_int32(&pointer_block[0]);
+ payload_offset = (Uint32)get_int32(&pointer_block[4]);
+
+ if(payload_size > max_payload_size) {
+ return am_eof;
+ }
+ }
+
+ if(!enif_alloc_binary(payload_size, &payload)) {
+ return posix_error_to_tuple(env, ENOMEM);
+ }
+
+ read_vec[0].iov_base = payload.data;
+ read_vec[0].iov_len = payload.size;
+
+ bytes_read = efile_preadv(d, payload_offset, read_vec, 1);
+
+ if(bytes_read < 0) {
+ enif_release_binary(&payload);
+ return posix_error_to_tuple(env, d->posix_errno);
+ } else if(bytes_read == 0) {
+ enif_release_binary(&payload);
+
+ return enif_make_tuple2(env, am_ok,
+ enif_make_tuple3(env,
+ enif_make_uint(env, payload_size),
+ enif_make_uint(env, payload_offset),
+ am_eof));
+ }
+
+ if(bytes_read < payload.size && !enif_realloc_binary(&payload, bytes_read)) {
+ ERTS_INTERNAL_ERROR("Failed to shrink ipread payload.");
+ }
+
+ return enif_make_tuple2(env, am_ok,
+ enif_make_tuple3(env,
+ enif_make_uint(env, payload_size),
+ enif_make_uint(env, payload_offset),
+ enif_make_binary(env, &payload)));
+}
+
+static ERL_NIF_TERM get_handle_nif_impl(efile_data_t *d, ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ if(argc != 0) {
+ return enif_make_badarg(env);
+ }
+
+ return efile_get_handle(env, d);
+}
+
+static ERL_NIF_TERM read_info_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_fileinfo_t info = {0};
+ efile_path_t path;
+ int follow_links;
+
+ if(argc != 2 || !enif_get_int(env, argv[1], &follow_links)) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_read_info(&path, follow_links, &info))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ /* #file_info as declared in file.hrl */
+ return enif_make_tuple(env, 14,
+ am_file_info,
+ enif_make_uint64(env, info.size),
+ efile_filetype_to_atom(info.type),
+ efile_access_to_atom(info.access),
+ enif_make_int64(env, MAX(EFILE_MIN_FILETIME, info.a_time)),
+ enif_make_int64(env, MAX(EFILE_MIN_FILETIME, info.m_time)),
+ enif_make_int64(env, MAX(EFILE_MIN_FILETIME, info.c_time)),
+ enif_make_uint(env, info.mode),
+ enif_make_uint(env, info.links),
+ enif_make_uint(env, info.major_device),
+ enif_make_uint(env, info.minor_device),
+ enif_make_uint(env, info.inode),
+ enif_make_uint(env, info.uid),
+ enif_make_uint(env, info.gid)
+ );
+}
+
+static ERL_NIF_TERM set_permissions_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+ unsigned int permissions;
+
+ if(argc != 2 || !enif_get_uint(env, argv[1], &permissions)) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_set_permissions(&path, permissions))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM set_owner_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+ int uid, gid;
+
+ if(argc != 3 || !enif_get_int(env, argv[1], &uid)
+ || !enif_get_int(env, argv[2], &gid)) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_set_owner(&path, uid, gid))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM set_time_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ Sint64 accessed, modified, created;
+ efile_path_t path;
+
+ if(argc != 4 || !enif_get_int64(env, argv[1], &accessed)
+ || !enif_get_int64(env, argv[2], &modified)
+ || !enif_get_int64(env, argv[3], &created)) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_set_time(&path, accessed, modified, created))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM read_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+ ERL_NIF_TERM result;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_read_link(env, &path, &result))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM list_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+ ERL_NIF_TERM result;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_list_dir(env, &path, &result))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM rename_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t existing_path, new_path;
+
+ if(argc != 2) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &existing_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_marshal_path(env, argv[1], &new_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_rename(&existing_path, &new_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM make_hard_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t existing_path, new_path;
+
+ if(argc != 2) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &existing_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_marshal_path(env, argv[1], &new_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_make_hard_link(&existing_path, &new_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM make_soft_link_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t existing_path, new_path;
+
+ if(argc != 2) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &existing_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_marshal_path(env, argv[1], &new_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_make_soft_link(&existing_path, &new_path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM make_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_make_dir(&path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM del_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_del_file(&path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM del_dir_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_del_dir(&path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+static ERL_NIF_TERM get_device_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ ERL_NIF_TERM result;
+ int device_index;
+
+ if(argc != 1 || !enif_get_int(env, argv[0], &device_index)) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_get_device_cwd(env, device_index, &result))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM get_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+ ERL_NIF_TERM result;
+
+ if(argc != 0) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_get_cwd(env, &result))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return enif_make_tuple2(env, am_ok, result);
+}
+
+static ERL_NIF_TERM set_cwd_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_set_cwd(&path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return am_ok;
+}
+
+/** @brief Reads an entire file into \c result, stopping after \c size bytes or
+ * EOF. It will read until EOF if size is 0. */
+static posix_errno_t read_file(efile_data_t *d, size_t size, ErlNifBinary *result) {
+ size_t initial_buffer_size;
+ ssize_t bytes_read;
+
+ if(size == 0) {
+ initial_buffer_size = 16 << 10;
+ } else {
+ initial_buffer_size = size;
+ }
+
+ if(!enif_alloc_binary(initial_buffer_size, result)) {
+ return ENOMEM;
+ }
+
+ bytes_read = 0;
+
+ for(;;) {
+ ssize_t block_bytes_read;
+ SysIOVec read_vec[1];
+
+ read_vec[0].iov_base = result->data + bytes_read;
+ read_vec[0].iov_len = result->size - bytes_read;
+
+ block_bytes_read = efile_readv(d, read_vec, 1);
+
+ if(block_bytes_read < 0) {
+ enif_release_binary(result);
+ return d->posix_errno;
+ }
+
+ bytes_read += block_bytes_read;
+
+ if(block_bytes_read < (result->size - bytes_read)) {
+ /* EOF */
+ break;
+ } else if(bytes_read == size) {
+ break;
+ }
+
+ if(!enif_realloc_binary(result, bytes_read * 2)) {
+ enif_release_binary(result);
+ return ENOMEM;
+ }
+ }
+
+ /* The file may have shrunk since we queried its size, so we have to do
+ * this even when the size is known. */
+ if(bytes_read < result->size && !enif_realloc_binary(result, bytes_read)) {
+ ERTS_INTERNAL_ERROR("Failed to shrink read_file result.");
+ }
+
+ return 0;
+}
+
+static ERL_NIF_TERM read_file_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno, ignored;
+
+ efile_fileinfo_t info = {0};
+ efile_path_t path;
+ efile_data_t *d;
+
+ ErlNifBinary result;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_read_info(&path, 1, &info))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_open(&path, EFILE_MODE_READ, efile_resource_type, &d))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ posix_errno = read_file(d, info.size, &result);
+
+ erts_atomic32_set_acqb(&d->state, EFILE_STATE_CLOSED);
+ efile_close(d, &ignored);
+
+ if(posix_errno) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return enif_make_tuple2(env, am_ok, enif_make_binary(env, &result));
+}
+
+static ERL_NIF_TERM altname_nif(ErlNifEnv *env, int argc, const ERL_NIF_TERM argv[]) {
+ posix_errno_t posix_errno;
+
+ efile_path_t path;
+ ERL_NIF_TERM result;
+
+ if(argc != 1) {
+ return enif_make_badarg(env);
+ }
+
+ if((posix_errno = efile_marshal_path(env, argv[0], &path))) {
+ return posix_error_to_tuple(env, posix_errno);
+ } else if((posix_errno = efile_altname(env, &path, &result))) {
+ return posix_error_to_tuple(env, posix_errno);
+ }
+
+ return enif_make_tuple2(env, am_ok, result);
+}
diff --git a/erts/emulator/nifs/common/prim_file_nif.h b/erts/emulator/nifs/common/prim_file_nif.h
new file mode 100644
index 0000000000..b2e30c59dd
--- /dev/null
+++ b/erts/emulator/nifs/common/prim_file_nif.h
@@ -0,0 +1,243 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017-2018. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+typedef int posix_errno_t;
+
+enum efile_modes_t {
+ EFILE_MODE_READ = (1 << 0),
+ EFILE_MODE_WRITE = (1 << 1), /* Implies truncating file when used alone. */
+ EFILE_MODE_APPEND = (1 << 2),
+ EFILE_MODE_EXCLUSIVE = (1 << 3),
+ EFILE_MODE_SYNC = (1 << 4),
+
+ EFILE_MODE_SKIP_TYPE_CHECK = (1 << 5), /* Special for device files on Unix. */
+ EFILE_MODE_NO_TRUNCATE = (1 << 6), /* Special for reopening on VxWorks. */
+
+ EFILE_MODE_READ_WRITE = EFILE_MODE_READ | EFILE_MODE_WRITE
+};
+
+enum efile_access_t {
+ EFILE_ACCESS_NONE = 0,
+ EFILE_ACCESS_READ = 1,
+ EFILE_ACCESS_WRITE = 2,
+ EFILE_ACCESS_READ_WRITE = EFILE_ACCESS_READ | EFILE_ACCESS_WRITE
+};
+
+enum efile_seek_t {
+ EFILE_SEEK_BOF,
+ EFILE_SEEK_CUR,
+ EFILE_SEEK_EOF
+};
+
+enum efile_filetype_t {
+ EFILE_FILETYPE_DEVICE,
+ EFILE_FILETYPE_DIRECTORY,
+ EFILE_FILETYPE_REGULAR,
+ EFILE_FILETYPE_SYMLINK,
+ EFILE_FILETYPE_OTHER
+};
+
+enum efile_advise_t {
+ EFILE_ADVISE_NORMAL,
+ EFILE_ADVISE_RANDOM,
+ EFILE_ADVISE_SEQUENTIAL,
+ EFILE_ADVISE_WILL_NEED,
+ EFILE_ADVISE_DONT_NEED,
+ EFILE_ADVISE_NO_REUSE
+};
+
+enum efile_state_t {
+ EFILE_STATE_IDLE = 0,
+ EFILE_STATE_BUSY = 1,
+ EFILE_STATE_CLOSE_PENDING = 2,
+ EFILE_STATE_CLOSED = 3
+};
+
+typedef struct {
+ Sint64 size; /* Size of file */
+ Uint32 type; /* Type of file -- one of EFILE_FILETYPE_*. */
+ Uint32 access; /* Access to file -- one of EFILE_ACCESS_*. */
+ Uint32 mode; /* Access permissions -- bit field. */
+ Uint32 links; /* Number of links to file. */
+ Uint32 major_device; /* Major device or file system. */
+ Uint32 minor_device; /* Minor device (for devices). */
+ Uint32 inode; /* Inode number. */
+ Uint32 uid; /* User id of owner. */
+ Uint32 gid; /* Group id of owner. */
+ Sint64 a_time; /* Last time the file was accessed. */
+ Sint64 m_time; /* Last time the file was modified. */
+ Sint64 c_time; /* Windows: creation time, Unix: last inode
+ * change. */
+} efile_fileinfo_t;
+
+/* The smallest value that can be converted freely between universal, local,
+ * and POSIX time, as required by read_file_info/2. Corresponds to
+ * {{1902,1,1},{0,0,0}} */
+#define EFILE_MIN_FILETIME -2145916800
+
+/* Initializes an efile_data_t; must be used in efile_open on success. */
+#define EFILE_INIT_RESOURCE(__d, __modes) do { \
+ erts_atomic32_init_acqb(&(__d)->state, EFILE_STATE_IDLE); \
+ (__d)->posix_errno = 0; \
+ (__d)->modes = __modes; \
+ } while(0)
+
+typedef struct {
+ erts_atomic32_t state;
+
+ posix_errno_t posix_errno;
+ enum efile_modes_t modes;
+
+ ErlNifMonitor monitor;
+} efile_data_t;
+
+typedef ErlNifBinary efile_path_t;
+
+/* @brief Translates the given "raw name" into the format expected by the APIs
+ * used by the underlying implementation. The result is transient and does not
+ * need to be released.
+ *
+ * This may change the structure of the path and its results should never be
+ * passed on to the user. Refer to the OS-specific implementation for details.
+ *
+ * @param path The term to translate; it must have been encoded with
+ * prim_file:internal_native2name for compatibility reasons. */
+posix_errno_t efile_marshal_path(ErlNifEnv *env, ERL_NIF_TERM path, efile_path_t *result);
+
+/* @brief Returns the underlying handle as an implementation-defined term.
+ *
+ * This is an internal function intended to support tests and tricky
+ * operations like sendfile(2). */
+ERL_NIF_TERM efile_get_handle(ErlNifEnv *env, efile_data_t *d);
+
+/* @brief Read until EOF or the given iovec has been filled.
+ *
+ * @return -1 on failure, or the number of bytes read on success. The return
+ * value will be 0 if no bytes could be read before EOF or the end of the
+ * iovec. */
+Sint64 efile_readv(efile_data_t *d, SysIOVec *iov, int iovlen);
+
+/* @brief Write the entirety of the given iovec.
+ *
+ * @return -1 on failure, or the number of bytes written on success. "Partial"
+ * failures will be reported with -1 and not the number of bytes we managed to
+ * write to disk before the failure. */
+Sint64 efile_writev(efile_data_t *d, SysIOVec *iov, int iovlen);
+
+/* @brief As \c efile_readv, but starting from a file offset. */
+Sint64 efile_preadv(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen);
+
+/* @brief As \c efile_writev, but starting from a file offset. */
+Sint64 efile_pwritev(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen);
+
+int efile_seek(efile_data_t *d, enum efile_seek_t seek, Sint64 offset, Sint64 *new_position);
+
+int efile_sync(efile_data_t *d, int data_only);
+
+int efile_advise(efile_data_t *d, Sint64 offset, Sint64 length, enum efile_advise_t advise);
+int efile_allocate(efile_data_t *d, Sint64 offset, Sint64 length);
+int efile_truncate(efile_data_t *d);
+
+posix_errno_t efile_open(const efile_path_t *path, enum efile_modes_t modes,
+ ErlNifResourceType *nif_type, efile_data_t **d);
+
+/** @brief Closes a file. The file must have entered the CLOSED state prior to
+ * calling this to prevent double close.
+ *
+ * Note that the file is completely invalid after this point, so the error code
+ * is provided in \c error rather than d->posix_errno. */
+int efile_close(efile_data_t *d, posix_errno_t *error);
+
+/* **** **** **** **** **** **** **** **** **** **** **** **** **** **** **** */
+
+posix_errno_t efile_read_info(const efile_path_t *path, int follow_link, efile_fileinfo_t *result);
+
+/** @brief Sets the file times to the given values. Refer to efile_fileinfo_t
+ * for a description of each. */
+posix_errno_t efile_set_time(const efile_path_t *path, Sint64 a_time, Sint64 m_time, Sint64 c_time);
+
+/** @brief On Unix, this sets the file permissions according to the docs for
+ * file:write_file_info/2. On Windows it uses the "owner write permission" flag
+ * to toggle whether the file is read-only or not. */
+posix_errno_t efile_set_permissions(const efile_path_t *path, Uint32 permissions);
+
+/** @brief On Unix, this will set the owner/group to the given values. It will
+ * do nothing on other platforms. */
+posix_errno_t efile_set_owner(const efile_path_t *path, Sint32 owner, Sint32 group);
+
+/** @brief Resolves the final path of the given link. */
+posix_errno_t efile_read_link(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result);
+
+/** @brief Lists the contents of the given directory.
+ * @param result [out] A list of all the directory/file names contained in the
+ * given directory. */
+posix_errno_t efile_list_dir(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result);
+
+/** @brief Changes the name of an existing file or directory, from old_path
+ * to new_path.
+ *
+ * If old_path and new_path refer to the same file or directory, it does
+ * nothing and returns success. Otherwise if new_path already exists, it will
+ * be deleted and replaced by src subject to the following conditions:
+ *
+ * If old_path is a directory, new_path may be an empty directory.
+ * If old_path is a file, new_path may be a file.
+ *
+ * Neither of these are guaranteed to be atomic. In any other situation where
+ * new_path already exists, the rename will fail.
+ *
+ * Some possible error codes:
+ *
+ * - EACCES: Either paths or one of their parent directories can't be read
+ * and/or written.
+ * - EEXIST: new_path is a non-empty directory.
+ * - EINVAL: old_path is a root directory or new_path is a subdirectory
+ * of new_path.
+ * - EISDIR: new_path is a directory, but old_path is not.
+ * - ENOTDIR: old_path is a directory, but new_path is not.
+ * - ENOENT: old_path doesn't exist, or either path is "".
+ * - EXDEV: The paths are on different filesystems.
+ *
+ * The implementation of rename may allow cross-filesystem renames,
+ * but the caller should be prepared to emulate it with copy and
+ * delete if errno is EXDEV. */
+posix_errno_t efile_rename(const efile_path_t *old_path, const efile_path_t *new_path);
+
+posix_errno_t efile_make_hard_link(const efile_path_t *existing_path, const efile_path_t *new_path);
+posix_errno_t efile_make_soft_link(const efile_path_t *existing_path, const efile_path_t *new_path);
+posix_errno_t efile_make_dir(const efile_path_t *path);
+
+posix_errno_t efile_del_file(const efile_path_t *path);
+posix_errno_t efile_del_dir(const efile_path_t *path);
+
+posix_errno_t efile_get_cwd(ErlNifEnv *env, ERL_NIF_TERM *result);
+posix_errno_t efile_set_cwd(const efile_path_t *path);
+
+/** @brief A Windows-specific function for returning the working directory of a
+ * given device.
+ *
+ * @param device_index The drive index; 1 for A, 2 for B, etc.
+ * @param result [out] The working directory of the given device
+ */
+posix_errno_t efile_get_device_cwd(ErlNifEnv *env, int device_index, ERL_NIF_TERM *result);
+
+/** @brief A Windows-specific function for returning the 8.3-name of a given
+ * file or directory. */
+posix_errno_t efile_altname(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result);
diff --git a/erts/emulator/nifs/unix/unix_prim_file.c b/erts/emulator/nifs/unix/unix_prim_file.c
new file mode 100644
index 0000000000..169b193993
--- /dev/null
+++ b/erts/emulator/nifs/unix/unix_prim_file.c
@@ -0,0 +1,947 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017-2018. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#ifdef VALGRIND
+# include <valgrind/memcheck.h>
+#endif
+
+#include "prim_file_nif.h"
+
+#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__)
+#define __DARWIN__ 1
+#endif
+
+#if defined(__DARWIN__) || defined(HAVE_LINUX_FALLOC_H) || defined(HAVE_POSIX_FALLOCATE)
+#include <fcntl.h>
+#endif
+
+#ifdef HAVE_LINUX_FALLOC_H
+#include <linux/falloc.h>
+#endif
+
+#include <utime.h>
+
+/* Macros for testing file types. */
+#ifdef NO_UMASK
+#define FILE_MODE 0644
+#define DIR_MODE 0755
+#else
+#define FILE_MODE 0666
+#define DIR_MODE 0777
+#endif
+
+/* Old platforms might not have IOV_MAX defined. */
+#if !defined(IOV_MAX) && defined(UIO_MAXIOV)
+#define IOV_MAX UIO_MAXIOV
+#elif !defined(IOV_MAX)
+#define IOV_MAX 16
+#endif
+
+typedef struct {
+ efile_data_t common;
+ int fd;
+} efile_unix_t;
+
+static int has_invalid_null_termination(const ErlNifBinary *path) {
+ const char *null_pos, *end_pos;
+
+ null_pos = memchr(path->data, '\0', path->size);
+ end_pos = (const char*)&path->data[path->size] - 1;
+
+ if(null_pos == NULL) {
+ return 1;
+ }
+
+ /* prim_file:internal_name2native sometimes feeds us data that is "doubly"
+ * NUL-terminated, so we'll accept any number of trailing NULs so long as
+ * they aren't interrupted by anything else. */
+ while(null_pos < end_pos && (*null_pos) == '\0') {
+ null_pos++;
+ }
+
+ return null_pos != end_pos;
+}
+
+posix_errno_t efile_marshal_path(ErlNifEnv *env, ERL_NIF_TERM path, efile_path_t *result) {
+ if(!enif_inspect_binary(env, path, result)) {
+ return EINVAL;
+ }
+
+ if(has_invalid_null_termination(result)) {
+ return EINVAL;
+ }
+
+ return 0;
+}
+
+ERL_NIF_TERM efile_get_handle(ErlNifEnv *env, efile_data_t *d) {
+ efile_unix_t *u = (efile_unix_t*)d;
+
+ ERL_NIF_TERM result;
+ unsigned char *bits;
+
+ bits = enif_make_new_binary(env, sizeof(u->fd), &result);
+ memcpy(bits, &u->fd, sizeof(u->fd));
+
+ return result;
+}
+
+static int open_file_type_check(const efile_path_t *path, int fd) {
+ struct stat file_info;
+ int error;
+
+#ifndef HAVE_FSTAT
+ error = stat((const char*)path->data, &file_info);
+ (void)fd;
+#else
+ error = fstat(fd, &file_info);
+ (void)path;
+#endif
+
+ if(error < 0) {
+ /* If we failed to stat assume success and let the next call handle the
+ * error. The old driver checked whether the file was to be used
+ * immediately in a read within the call, but the new implementation
+ * never does that. */
+ return 1;
+ }
+
+ /* Allow everything that isn't a directory, and error out on the next call
+ * if it's unsupported. */
+ if(S_ISDIR(file_info.st_mode)) {
+ return 0;
+ }
+
+ return 1;
+}
+
+posix_errno_t efile_open(const efile_path_t *path, enum efile_modes_t modes,
+ ErlNifResourceType *nif_type, efile_data_t **d) {
+
+ int flags, fd;
+
+ flags = 0;
+
+ if(modes & EFILE_MODE_READ && !(modes & EFILE_MODE_WRITE)) {
+ flags |= O_RDONLY;
+ } else if(modes & EFILE_MODE_WRITE && !(modes & EFILE_MODE_READ)) {
+ if(!(modes & EFILE_MODE_NO_TRUNCATE)) {
+ flags |= O_TRUNC;
+ }
+
+ flags |= O_WRONLY | O_CREAT;
+ } else if(modes & EFILE_MODE_READ_WRITE) {
+ flags |= O_RDWR | O_CREAT;
+ } else {
+ return EINVAL;
+ }
+
+ if(modes & EFILE_MODE_APPEND) {
+ flags &= ~O_TRUNC;
+ flags |= O_APPEND;
+ }
+
+ if(modes & EFILE_MODE_EXCLUSIVE) {
+ flags |= O_EXCL;
+ }
+
+ if(modes & EFILE_MODE_SYNC) {
+#ifndef O_SYNC
+ return ENOTSUP;
+#else
+ flags |= O_SYNC;
+#endif
+ }
+
+ do {
+ fd = open((const char*)path->data, flags, FILE_MODE);
+ } while(fd == -1 && errno == EINTR);
+
+ if(fd != -1) {
+ efile_unix_t *u;
+
+ if(!(modes & EFILE_MODE_SKIP_TYPE_CHECK) && !open_file_type_check(path, fd)) {
+ close(fd);
+
+ /* This is blatantly incorrect, but we're documented as returning
+ * this for everything that isn't a file. */
+ return EISDIR;
+ }
+
+ u = (efile_unix_t*)enif_alloc_resource(nif_type, sizeof(efile_unix_t));
+ u->fd = fd;
+
+ EFILE_INIT_RESOURCE(&u->common, modes);
+ (*d) = &u->common;
+
+ return 0;
+ }
+
+ (*d) = NULL;
+ return errno;
+}
+
+int efile_close(efile_data_t *d, posix_errno_t *error) {
+ efile_unix_t *u = (efile_unix_t*)d;
+ int fd;
+
+ ASSERT(enif_thread_type() == ERL_NIF_THR_DIRTY_IO_SCHEDULER);
+ ASSERT(erts_atomic32_read_nob(&d->state) == EFILE_STATE_CLOSED);
+ ASSERT(u->fd != -1);
+
+ fd = u->fd;
+ u->fd = -1;
+
+ enif_release_resource(d);
+
+ /* close(2) either always closes (*BSD, Linux) or leaves the fd in an
+ * undefined state (POSIX 2008, Solaris), so we must not retry on EINTR. */
+
+ if(close(fd) < 0) {
+ *error = errno;
+ return 0;
+ }
+
+ return 1;
+}
+
+static void shift_iov(SysIOVec **iov, int *iovlen, ssize_t shift) {
+ SysIOVec *head_vec = (*iov);
+
+ ASSERT(shift >= 0);
+
+ while(shift > 0) {
+ ASSERT(head_vec < &(*iov)[*iovlen]);
+
+ if(shift < head_vec->iov_len) {
+ head_vec->iov_base = (char*)head_vec->iov_base + shift;
+ head_vec->iov_len -= shift;
+ break;
+ } else {
+ shift -= head_vec->iov_len;
+ head_vec++;
+ }
+ }
+
+ (*iovlen) -= head_vec - (*iov);
+ (*iov) = head_vec;
+}
+
+Sint64 efile_readv(efile_data_t *d, SysIOVec *iov, int iovlen) {
+ efile_unix_t *u = (efile_unix_t*)d;
+
+ Sint64 bytes_read;
+ ssize_t result;
+
+ bytes_read = 0;
+
+ do {
+ int use_fallback = 0;
+
+ if(iovlen < 1) {
+ result = 0;
+ break;
+ }
+
+ /* writev(2) implies readv(2) */
+#ifdef HAVE_WRITEV
+ result = readv(u->fd, iov, MIN(IOV_MAX, iovlen));
+
+ /* Fall back to using read(2) if readv(2) reports that the combined
+ * size of iov is greater than SSIZE_T_MAX. */
+ use_fallback = (result < 0 && errno == EINVAL);
+#else
+ use_fallback = 1;
+#endif
+
+ if(use_fallback) {
+ result = read(u->fd, iov->iov_base, iov->iov_len);
+ }
+
+ if(result > 0) {
+ shift_iov(&iov, &iovlen, result);
+ bytes_read += result;
+ }
+ } while(result > 0 || (result < 0 && errno == EINTR));
+
+ u->common.posix_errno = errno;
+
+ if(result == 0 && bytes_read > 0) {
+ return bytes_read;
+ }
+
+ return result;
+}
+
+Sint64 efile_writev(efile_data_t *d, SysIOVec *iov, int iovlen) {
+ efile_unix_t *u = (efile_unix_t*)d;
+
+ Sint64 bytes_written;
+ ssize_t result;
+
+ bytes_written = 0;
+
+ do {
+ int use_fallback = 0;
+
+ if(iovlen < 1) {
+ result = 0;
+ break;
+ }
+
+#ifdef HAVE_WRITEV
+ result = writev(u->fd, iov, MIN(IOV_MAX, iovlen));
+
+ /* Fall back to using write(2) if writev(2) reports that the combined
+ * size of iov is greater than SSIZE_T_MAX. */
+ use_fallback = (result < 0 && errno == EINVAL);
+#else
+ use_fallback = 1;
+#endif
+
+ if(use_fallback) {
+ result = write(u->fd, iov->iov_base, iov->iov_len);
+ }
+
+ if(result > 0) {
+ shift_iov(&iov, &iovlen, result);
+ bytes_written += result;
+ }
+ } while(result > 0 || (result < 0 && errno == EINTR));
+
+ u->common.posix_errno = errno;
+
+ if(result == 0 && bytes_written > 0) {
+ return bytes_written;
+ }
+
+ return result;
+}
+
+Sint64 efile_preadv(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+ efile_unix_t *u = (efile_unix_t*)d;
+
+ Uint64 bytes_read;
+ Sint64 result;
+
+#if !defined(HAVE_PREADV) && !defined(HAVE_PREAD)
+ /* This function is documented as leaving the file position undefined, but
+ * the old driver always reset it so there's probably code in the wild that
+ * relies on this behavior. */
+ off_t original_position = lseek(u->fd, 0, SEEK_CUR);
+
+ if(original_position < 0 || lseek(u->fd, offset, SEEK_SET) < 0) {
+ u->common.posix_errno = errno;
+ return -1;
+ }
+#endif
+
+ bytes_read = 0;
+
+ do {
+ if(iovlen < 1) {
+ result = 0;
+ break;
+ }
+
+#if defined(HAVE_PREADV)
+ result = preadv(u->fd, iov, MIN(IOV_MAX, iovlen), offset);
+#elif defined(HAVE_PREAD)
+ result = pread(u->fd, iov->iov_base, iov->iov_len, offset);
+#else
+ result = read(u->fd, iov->iov_base, iov->iov_len);
+#endif
+
+ if(result > 0) {
+ shift_iov(&iov, &iovlen, result);
+ bytes_read += result;
+ offset += result;
+ }
+ } while(result > 0 || (result < 0 && errno == EINTR));
+
+ u->common.posix_errno = errno;
+
+#if !defined(HAVE_PREADV) && !defined(HAVE_PREAD)
+ if(result >= 0) {
+ if(lseek(u->fd, original_position, SEEK_SET) < 0) {
+ u->common.posix_errno = errno;
+ return -1;
+ }
+ }
+#endif
+
+ if(result == 0 && bytes_read > 0) {
+ return bytes_read;
+ }
+
+ return result;
+}
+
+Sint64 efile_pwritev(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+ efile_unix_t *u = (efile_unix_t*)d;
+
+ Sint64 bytes_written;
+ ssize_t result;
+
+#if !defined(HAVE_PWRITEV) && !defined(HAVE_PWRITE)
+ off_t original_position = lseek(u->fd, 0, SEEK_CUR);
+
+ if(original_position < 0 || lseek(u->fd, offset, SEEK_SET) < 0) {
+ u->common.posix_errno = errno;
+ return -1;
+ }
+#endif
+
+ bytes_written = 0;
+
+ do {
+ if(iovlen < 1) {
+ result = 0;
+ break;
+ }
+
+#if defined(HAVE_PWRITEV)
+ result = pwritev(u->fd, iov, MIN(IOV_MAX, iovlen), offset);
+#elif defined(HAVE_PWRITE)
+ result = pwrite(u->fd, iov->iov_base, iov->iov_len, offset);
+#else
+ result = write(u->fd, iov->iov_base, iov->iov_len);
+#endif
+
+ if(result > 0) {
+ shift_iov(&iov, &iovlen, result);
+ bytes_written += result;
+ offset += result;
+ }
+ } while(result > 0 || (result < 0 && errno == EINTR));
+
+ u->common.posix_errno = errno;
+
+#if !defined(HAVE_PWRITEV) && !defined(HAVE_PWRITE)
+ if(result >= 0) {
+ if(lseek(u->fd, original_position, SEEK_SET) < 0) {
+ u->common.posix_errno = errno;
+ return -1;
+ }
+ }
+#endif
+
+ if(result == 0 && bytes_written > 0) {
+ return bytes_written;
+ }
+
+ return result;
+}
+
+int efile_seek(efile_data_t *d, enum efile_seek_t seek, Sint64 offset, Sint64 *new_position) {
+ efile_unix_t *u = (efile_unix_t*)d;
+ off_t result;
+ int whence;
+
+ switch(seek) {
+ case EFILE_SEEK_BOF: whence = SEEK_SET; break;
+ case EFILE_SEEK_CUR: whence = SEEK_CUR; break;
+ case EFILE_SEEK_EOF: whence = SEEK_END; break;
+ default: ERTS_INTERNAL_ERROR("Invalid seek parameter");
+ }
+
+ result = lseek(u->fd, offset, whence);
+
+ /*
+ * The man page for lseek (on SunOs 5) says:
+ *
+ * "if fildes is a remote file descriptor and offset is negative, lseek()
+ * returns the file pointer even if it is negative."
+ */
+ if(result < 0 && errno == 0) {
+ errno = EINVAL;
+ }
+
+ if(result < 0) {
+ u->common.posix_errno = errno;
+ return 0;
+ }
+
+ (*new_position) = result;
+
+ return 1;
+}
+
+int efile_sync(efile_data_t *d, int data_only) {
+ efile_unix_t *u = (efile_unix_t*)d;
+
+#if defined(HAVE_FDATASYNC) && !defined(__DARWIN__)
+ if(data_only) {
+ if(fdatasync(u->fd) < 0) {
+ u->common.posix_errno = errno;
+ return 0;
+ }
+
+ return 1;
+ }
+#endif
+
+#if defined(__DARWIN__) && defined(F_FULLFSYNC)
+ if(fcntl(u->fd, F_FULLFSYNC) < 0) {
+#else
+ if(fsync(u->fd) < 0) {
+#endif
+ u->common.posix_errno = errno;
+ return 0;
+ }
+
+ return 1;
+}
+
+int efile_advise(efile_data_t *d, Sint64 offset, Sint64 length, enum efile_advise_t advise) {
+#ifdef HAVE_POSIX_FADVISE
+ efile_unix_t *u = (efile_unix_t*)d;
+ int p_advise;
+
+ switch(advise) {
+ case EFILE_ADVISE_NORMAL: p_advise = POSIX_FADV_NORMAL; break;
+ case EFILE_ADVISE_RANDOM: p_advise = POSIX_FADV_RANDOM; break;
+ case EFILE_ADVISE_SEQUENTIAL: p_advise = POSIX_FADV_SEQUENTIAL; break;
+ case EFILE_ADVISE_WILL_NEED: p_advise = POSIX_FADV_WILLNEED; break;
+ case EFILE_ADVISE_DONT_NEED: p_advise = POSIX_FADV_DONTNEED; break;
+ case EFILE_ADVISE_NO_REUSE: p_advise = POSIX_FADV_NOREUSE; break;
+ default:
+ u->common.posix_errno = EINVAL;
+ return 0;
+ }
+
+ if(posix_fadvise(u->fd, offset, length, p_advise) < 0) {
+ u->common.posix_errno = errno;
+ return 0;
+ }
+
+ return 1;
+#else
+ /* We'll pretend to support this syscall as it's only a recommendation even
+ * on systems that do support it. */
+ return 1;
+#endif
+}
+
+int efile_allocate(efile_data_t *d, Sint64 offset, Sint64 length) {
+ efile_unix_t *u = (efile_unix_t*)d;
+ int ret = -1;
+
+ /* We prefer OS-specific methods, but fall back to posix_fallocate on
+ * failure. It's unclear whether this has any practical benefit on
+ * modern systems, but the old driver did it. */
+
+#if defined(HAVE_FALLOCATE)
+ /* Linux-specific */
+ do {
+ ret = fallocate(u->fd, FALLOC_FL_KEEP_SIZE, offset, length);
+ } while(ret < 0 && errno == EINTR);
+#elif defined(F_PREALLOCATE)
+ /* Mac-specific */
+ fstore_t fs = {};
+
+ fs.fst_flags = F_ALLOCATECONTIG;
+ fs.fst_posmode = F_VOLPOSMODE;
+ fs.fst_offset = offset;
+ fs.fst_length = length;
+
+ ret = fcntl(u->fd, F_PREALLOCATE, &fs);
+ if(ret < 0) {
+ fs.fst_flags = F_ALLOCATEALL;
+ ret = fcntl(u->fd, F_PREALLOCATE, &fs);
+ }
+#elif !defined(HAVE_POSIX_FALLOCATE)
+ u->common.posix_errno = ENOTSUP;
+ return 0;
+#endif
+
+#ifdef HAVE_POSIX_FALLOCATE
+ if(ret < 0) {
+ do {
+ ret = posix_fallocate(u->fd, offset, length);
+
+ /* On Linux and Solaris for example, posix_fallocate() returns a
+ * positive error number on error and it does not set errno. On
+ * FreeBSD however (9.0 at least), it returns -1 on error and it
+ * sets errno. */
+ if (ret > 0) {
+ errno = ret;
+ ret = -1;
+ }
+ } while(ret < 0 && errno == EINTR);
+ }
+#endif
+
+ if(ret < 0) {
+ u->common.posix_errno = errno;
+ return 0;
+ }
+
+ return 1;
+}
+
+int efile_truncate(efile_data_t *d) {
+ efile_unix_t *u = (efile_unix_t*)d;
+ off_t offset;
+
+ offset = lseek(u->fd, 0, SEEK_CUR);
+
+ if(offset < 0) {
+ u->common.posix_errno = errno;
+ return 0;
+ }
+
+ if(ftruncate(u->fd, offset) < 0) {
+ u->common.posix_errno = errno;
+ return 0;
+ }
+
+ return 1;
+}
+
+posix_errno_t efile_read_info(const efile_path_t *path, int follow_links, efile_fileinfo_t *result) {
+ struct stat data;
+
+ if(follow_links) {
+ if(stat((const char*)path->data, &data) < 0) {
+ return errno;
+ }
+ } else {
+ if(lstat((const char*)path->data, &data) < 0) {
+ return errno;
+ }
+ }
+
+ if(S_ISCHR(data.st_mode) || S_ISBLK(data.st_mode)) {
+ result->type = EFILE_FILETYPE_DEVICE;
+ } else if(S_ISDIR(data.st_mode)) {
+ result->type = EFILE_FILETYPE_DIRECTORY;
+ } else if(S_ISREG(data.st_mode)) {
+ result->type = EFILE_FILETYPE_REGULAR;
+ } else if(S_ISLNK(data.st_mode)) {
+ result->type = EFILE_FILETYPE_SYMLINK;
+ } else {
+ result->type = EFILE_FILETYPE_OTHER;
+ }
+
+ result->a_time = (Sint64)data.st_atime;
+ result->m_time = (Sint64)data.st_mtime;
+ result->c_time = (Sint64)data.st_ctime;
+ result->size = data.st_size;
+
+ result->major_device = data.st_dev;
+ result->minor_device = data.st_rdev;
+ result->links = data.st_nlink;
+ result->inode = data.st_ino;
+ result->mode = data.st_mode;
+ result->uid = data.st_uid;
+ result->gid = data.st_gid;
+
+#ifndef NO_ACCESS
+ result->access = EFILE_ACCESS_NONE;
+
+ if(access((const char*)path->data, R_OK) == 0) {
+ result->access |= EFILE_ACCESS_READ;
+ }
+ if(access((const char*)path->data, W_OK) == 0) {
+ result->access |= EFILE_ACCESS_WRITE;
+ }
+#else
+ /* Just look at read/write access for owner. */
+ result->access = ((data.st_mode >> 6) & 07) >> 1;
+#endif
+
+ return 0;
+}
+
+posix_errno_t efile_set_permissions(const efile_path_t *path, Uint32 permissions) {
+ const mode_t MUTABLE_MODES = (S_ISUID | S_ISGID | S_IRWXU | S_IRWXG | S_IRWXO);
+ mode_t new_modes = permissions & MUTABLE_MODES;
+
+ if(chmod((const char*)path->data, new_modes) < 0) {
+ new_modes &= ~(S_ISUID | S_ISGID);
+
+ if (chmod((const char*)path->data, new_modes) < 0) {
+ return errno;
+ }
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_set_owner(const efile_path_t *path, Sint32 owner, Sint32 group) {
+ if(chown((const char*)path->data, owner, group) < 0) {
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_set_time(const efile_path_t *path, Sint64 a_time, Sint64 m_time, Sint64 c_time) {
+ struct utimbuf tval;
+
+ tval.actime = (time_t)a_time;
+ tval.modtime = (time_t)m_time;
+
+ (void)c_time;
+
+ if(utime((const char*)path->data, &tval) < 0) {
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_read_link(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+ ErlNifBinary result_bin;
+
+ if(!enif_alloc_binary(256, &result_bin)) {
+ return ENOMEM;
+ }
+
+ for(;;) {
+ ssize_t bytes_copied;
+
+ bytes_copied = readlink((const char*)path->data, (char*)result_bin.data,
+ result_bin.size);
+
+ if(bytes_copied <= 0) {
+ posix_errno_t saved_errno = errno;
+ enif_release_binary(&result_bin);
+ return saved_errno;
+ } else if(bytes_copied < result_bin.size) {
+ if(!enif_realloc_binary(&result_bin, bytes_copied)) {
+ enif_release_binary(&result_bin);
+ return ENOMEM;
+ }
+
+ (*result) = enif_make_binary(env, &result_bin);
+
+ return 0;
+ }
+
+ /* The result didn't fit into the buffer, so we'll try again with a
+ * larger one. */
+
+ if(!enif_realloc_binary(&result_bin, result_bin.size * 2)) {
+ enif_release_binary(&result_bin);
+ return ENOMEM;
+ }
+ }
+}
+
+static int is_ignored_name(int name_length, const char *name) {
+ if(name_length == 1 && name[0] == '.') {
+ return 1;
+ } else if(name_length == 2 && memcmp(name, "..", 2) == 0) {
+ return 1;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_list_dir(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+ ERL_NIF_TERM list_head;
+
+ struct dirent *dir_entry;
+ DIR *dir_stream;
+
+ dir_stream = opendir((const char*)path->data);
+ if(dir_stream == NULL) {
+ posix_errno_t saved_errno = errno;
+ *result = enif_make_list(env, 0);
+ return saved_errno;
+ }
+
+ list_head = enif_make_list(env, 0);
+ dir_entry = readdir(dir_stream);
+
+ while(dir_entry != NULL) {
+ int name_length = strlen(dir_entry->d_name);
+
+ if(!is_ignored_name(name_length, dir_entry->d_name)) {
+ unsigned char *name_bytes;
+ ERL_NIF_TERM name_term;
+
+ name_bytes = enif_make_new_binary(env, name_length, &name_term);
+ sys_memcpy(name_bytes, dir_entry->d_name, name_length);
+
+ list_head = enif_make_list_cell(env, name_term, list_head);
+ }
+
+ dir_entry = readdir(dir_stream);
+ }
+
+ (*result) = list_head;
+ closedir(dir_stream);
+
+ return 0;
+}
+
+posix_errno_t efile_rename(const efile_path_t *old_path, const efile_path_t *new_path) {
+ if(rename((const char*)old_path->data, (const char*)new_path->data) < 0) {
+ if(errno == ENOTEMPTY) {
+ return EEXIST;
+ }
+
+ if(strcmp((const char*)old_path->data, "/") == 0) {
+ /* Alpha reports renaming / as EBUSY and Linux reports it as EACCES
+ * instead of EINVAL.*/
+ return EINVAL;
+ }
+
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_make_hard_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+ if(link((const char*)existing_path->data, (const char*)new_path->data) < 0) {
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_make_soft_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+ if(symlink((const char*)existing_path->data, (const char*)new_path->data) < 0) {
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_make_dir(const efile_path_t *path) {
+#ifdef NO_MKDIR_MODE
+ if(mkdir((const char*)path->data) < 0) {
+#else
+ if(mkdir((const char*)path->data, DIR_MODE) < 0) {
+#endif
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_del_file(const efile_path_t *path) {
+ if(unlink((const char*)path->data) < 0) {
+ /* Linux sets the wrong error code. */
+ if(errno == EISDIR) {
+ return EPERM;
+ }
+
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_del_dir(const efile_path_t *path) {
+ if(rmdir((const char*)path->data) < 0) {
+ posix_errno_t saved_errno = errno;
+
+ if(saved_errno == ENOTEMPTY) {
+ saved_errno = EEXIST;
+ }
+
+ /* The error code might be wrong if we're trying to delete the current
+ * directory. */
+ if(saved_errno == EEXIST) {
+ struct stat path_stat, cwd_stat;
+ int has_stat;
+
+ has_stat = (stat((const char*)path->data, &path_stat) == 0);
+ has_stat &= (stat(".", &cwd_stat) == 0);
+
+ if(has_stat && path_stat.st_ino == cwd_stat.st_ino) {
+ if(path_stat.st_dev == cwd_stat.st_dev) {
+ return EINVAL;
+ }
+ }
+ }
+
+ return saved_errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_set_cwd(const efile_path_t *path) {
+ if(chdir((const char*)path->data) < 0) {
+ return errno;
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_get_device_cwd(ErlNifEnv *env, int device_index, ERL_NIF_TERM *result) {
+ (void)device_index;
+ (void)result;
+ (void)env;
+
+ return ENOTSUP;
+}
+
+posix_errno_t efile_get_cwd(ErlNifEnv *env, ERL_NIF_TERM *result) {
+ ErlNifBinary result_bin;
+ size_t bytes_copied;
+
+ if(!enif_alloc_binary(256, &result_bin)) {
+ return ENOMEM;
+ }
+
+ while(getcwd((char*)result_bin.data, result_bin.size) == NULL) {
+ posix_errno_t saved_errno = errno;
+
+ if(saved_errno != ERANGE) {
+ enif_release_binary(&result_bin);
+ return saved_errno;
+ } else {
+ if(!enif_realloc_binary(&result_bin, result_bin.size * 2)) {
+ enif_release_binary(&result_bin);
+ return ENOMEM;
+ }
+ }
+ }
+
+ /* getcwd(2) guarantees null-termination. */
+ bytes_copied = strlen((const char*)result_bin.data);
+
+ if(!enif_realloc_binary(&result_bin, bytes_copied)) {
+ enif_release_binary(&result_bin);
+ return ENOMEM;
+ }
+
+ (*result) = enif_make_binary(env, &result_bin);
+
+ return 0;
+}
+
+posix_errno_t efile_altname(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+ (void)path;
+ (void)result;
+
+ return ENOTSUP;
+}
diff --git a/erts/emulator/nifs/win32/win_prim_file.c b/erts/emulator/nifs/win32/win_prim_file.c
new file mode 100644
index 0000000000..d0aa70542f
--- /dev/null
+++ b/erts/emulator/nifs/win32/win_prim_file.c
@@ -0,0 +1,1526 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson 2017-2018. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * %CopyrightEnd%
+ */
+
+#include "erl_nif.h"
+#include "config.h"
+#include "sys.h"
+
+#include "prim_file_nif.h"
+
+#include <winioctl.h>
+#include <windows.h>
+#include <strsafe.h>
+#include <wchar.h>
+
+#define IS_SLASH(a) ((a) == L'\\' || (a) == L'/')
+
+#define FILE_SHARE_FLAGS (FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE)
+
+/* Long paths can either be in the file (?) or the device (.) namespace. UNC
+ * paths are always in the file namespace. */
+#define LP_FILE_PREFIX L"\\\\?\\"
+#define LP_DEV_PREFIX L"\\\\.\\"
+#define LP_UNC_PREFIX (LP_FILE_PREFIX L"UNC\\")
+
+#define LP_PREFIX_SIZE (sizeof(LP_FILE_PREFIX) - sizeof(WCHAR))
+#define LP_PREFIX_LENGTH (LP_PREFIX_SIZE / sizeof(WCHAR))
+
+#define LP_UNC_PREFIX_SIZE (sizeof(LP_UNC_PREFIX) - sizeof(WCHAR))
+#define LP_UNC_PREFIX_LENGTH (LP_UNC_PREFIX_SIZE / sizeof(WCHAR))
+
+#define IS_LONG_PATH(length, data) \
+ ((length) >= LP_PREFIX_LENGTH && \
+ (!sys_memcmp((data), LP_FILE_PREFIX, LP_PREFIX_SIZE) || \
+ !sys_memcmp((data), LP_DEV_PREFIX, LP_PREFIX_SIZE)))
+
+#define IS_LONG_UNC_PATH(length, data) \
+ ((length) >= LP_UNC_PREFIX_LENGTH && \
+ !sys_memcmp((data), LP_UNC_PREFIX, LP_UNC_PREFIX_SIZE))
+
+#define PATH_LENGTH(path) (path->size / sizeof(WCHAR) - 1)
+
+#define ASSERT_PATH_FORMAT(path) \
+ do { \
+ ASSERT(IS_LONG_PATH(PATH_LENGTH(path), (path)->data)); \
+ ASSERT(PATH_LENGTH(path) == wcslen((WCHAR*)path->data)); \
+ } while(0)
+
+#define TICKS_PER_SECOND (10000000ULL)
+#define EPOCH_DIFFERENCE (11644473600LL)
+
+#define FILETIME_TO_EPOCH(epoch, ft) \
+ do { \
+ ULARGE_INTEGER ull; \
+ ull.LowPart = (ft).dwLowDateTime; \
+ ull.HighPart = (ft).dwHighDateTime; \
+ (epoch) = ((ull.QuadPart / TICKS_PER_SECOND) - EPOCH_DIFFERENCE); \
+ } while(0)
+
+#define EPOCH_TO_FILETIME(ft, epoch) \
+ do { \
+ ULARGE_INTEGER ull; \
+ ull.QuadPart = (((epoch) + EPOCH_DIFFERENCE) * TICKS_PER_SECOND); \
+ (ft).dwLowDateTime = ull.LowPart; \
+ (ft).dwHighDateTime = ull.HighPart; \
+ } while(0)
+
+typedef struct {
+ efile_data_t common;
+ HANDLE handle;
+} efile_win_t;
+
+static int windows_to_posix_errno(DWORD last_error);
+
+static int has_invalid_null_termination(const ErlNifBinary *path) {
+ const WCHAR *null_pos, *end_pos;
+
+ null_pos = wmemchr((const WCHAR*)path->data, L'\0', path->size);
+ end_pos = (const WCHAR*)&path->data[path->size] - 1;
+
+ if(null_pos == NULL) {
+ return 1;
+ }
+
+ /* prim_file:internal_name2native sometimes feeds us data that is "doubly"
+ * NUL-terminated, so we'll accept any number of trailing NULs so long as
+ * they aren't interrupted by anything else. */
+ while(null_pos < end_pos && (*null_pos) == L'\0') {
+ null_pos++;
+ }
+
+ return null_pos != end_pos;
+}
+
+static posix_errno_t get_full_path(ErlNifEnv *env, WCHAR *input, efile_path_t *result) {
+ DWORD maximum_length, actual_length;
+ int add_long_prefix;
+
+ maximum_length = GetFullPathNameW(input, 0, NULL, NULL);
+ add_long_prefix = 0;
+
+ if(maximum_length == 0) {
+ /* POSIX doesn't have the concept of a "path error" in the same way
+ * Windows does, so we'll return ENOENT since that's what most POSIX
+ * APIs would return if they were fed such garbage. */
+ return ENOENT;
+ }
+
+ maximum_length += MAX(LP_PREFIX_LENGTH, LP_UNC_PREFIX_LENGTH);
+
+ if(!enif_alloc_binary(maximum_length * sizeof(WCHAR), result)) {
+ return ENOMEM;
+ }
+
+ actual_length = GetFullPathNameW(input, maximum_length, (WCHAR*)result->data, NULL);
+
+ if(actual_length < maximum_length) {
+ int is_long_path, maybe_unc_path;
+ WCHAR *path_start;
+
+ /* The APIs we use have varying path length limits and sometimes
+ * behave differently when given a long-path prefix, so it's simplest
+ * to always use long paths. */
+
+ is_long_path = IS_LONG_PATH(actual_length, result->data);
+ maybe_unc_path = !sys_memcmp(result->data, L"\\\\", sizeof(WCHAR) * 2);
+
+ if(maybe_unc_path && !is_long_path) {
+ /* \\localhost\c$\gurka -> \\?\UNC\localhost\c$\gurka */
+ sys_memmove(result->data + LP_UNC_PREFIX_SIZE,
+ &((WCHAR*)result->data)[2],
+ (actual_length - 1) * sizeof(WCHAR));
+ sys_memcpy(result->data, LP_UNC_PREFIX, LP_UNC_PREFIX_SIZE);
+ actual_length += LP_UNC_PREFIX_LENGTH;
+ } else if(!is_long_path) {
+ /* C:\gurka -> \\?\C:\gurka */
+ sys_memmove(result->data + LP_PREFIX_SIZE, result->data,
+ (actual_length + 1) * sizeof(WCHAR));
+ sys_memcpy(result->data, LP_FILE_PREFIX, LP_PREFIX_SIZE);
+ actual_length += LP_PREFIX_LENGTH;
+ }
+
+ path_start = (WCHAR*)result->data;
+
+ /* We're removing trailing slashes since quite a few APIs refuse to
+ * work with them, and none require them. We only check the last
+ * character since GetFullPathNameW folds slashes together. */
+ if(IS_SLASH(path_start[actual_length - 1])) {
+ if(path_start[actual_length - 2] != L':') {
+ path_start[actual_length - 1] = L'\0';
+ actual_length--;
+ }
+ }
+
+ if(!enif_realloc_binary(result, (actual_length + 1) * sizeof(WCHAR))) {
+ enif_release_binary(result);
+ return ENOMEM;
+ }
+
+ enif_make_binary(env, result);
+ return 0;
+ }
+
+ /* We may end up here if the current directory changes to something longer
+ * between/during GetFullPathName. There's nothing sensible we can do about
+ * this. */
+
+ enif_release_binary(result);
+
+ return EINVAL;
+}
+
+posix_errno_t efile_marshal_path(ErlNifEnv *env, ERL_NIF_TERM path, efile_path_t *result) {
+ ErlNifBinary raw_path;
+
+ if(!enif_inspect_binary(env, path, &raw_path)) {
+ return EINVAL;
+ } else if(raw_path.size % sizeof(WCHAR)) {
+ return EINVAL;
+ }
+
+ if(has_invalid_null_termination(&raw_path)) {
+ return EINVAL;
+ }
+
+ return get_full_path(env, (WCHAR*)raw_path.data, result);
+}
+
+ERL_NIF_TERM efile_get_handle(ErlNifEnv *env, efile_data_t *d) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ ERL_NIF_TERM result;
+ unsigned char *bits;
+
+ bits = enif_make_new_binary(env, sizeof(w->handle), &result);
+ memcpy(bits, &w->handle, sizeof(w->handle));
+
+ return result;
+}
+
+/** @brief Converts a native path to the preferred form in "erlang space,"
+ * without path-prefixes, forward-slashes, or NUL terminators. */
+static int normalize_path_result(ErlNifBinary *path) {
+ WCHAR *path_iterator, *path_start, *path_end;
+ int length;
+
+ path_start = (WCHAR*)path->data;
+ length = wcslen(path_start);
+
+ ASSERT(length < path->size / sizeof(WCHAR));
+
+ /* Get rid of the long-path prefix, if present. */
+
+ if(IS_LONG_UNC_PATH(length, path_start)) {
+ /* The first two characters (\\) are the same for both long and short
+ * UNC paths. */
+ sys_memmove(&path_start[2], &path_start[LP_UNC_PREFIX_LENGTH],
+ (length - LP_UNC_PREFIX_LENGTH) * sizeof(WCHAR));
+
+ length -= LP_UNC_PREFIX_LENGTH - 2;
+ } else if(IS_LONG_PATH(length, path_start)) {
+ length -= LP_PREFIX_LENGTH;
+
+ sys_memmove(path_start, &path_start[LP_PREFIX_LENGTH],
+ length * sizeof(WCHAR));
+ }
+
+ path_end = &path_start[length];
+ path_iterator = path_start;
+
+ /* Convert drive letters to lowercase, if present. */
+ if(length >= 2 && path_start[1] == L':') {
+ WCHAR drive_letter = path_start[0];
+
+ if(drive_letter >= L'A' && drive_letter <= L'Z') {
+ path_start[0] = drive_letter - L'A' + L'a';
+ }
+ }
+
+ while(path_iterator < path_end) {
+ if(*path_iterator == L'\\') {
+ *path_iterator = L'/';
+ }
+
+ path_iterator++;
+ }
+
+ /* Truncate the result to its actual length; we don't want to include the
+ * NUL terminator. */
+ return enif_realloc_binary(path, length * sizeof(WCHAR));
+}
+
+/* @brief Checks whether all the given attributes are set on the object at the
+ * given path. Note that it assumes false on errors. */
+static int has_file_attributes(const efile_path_t *path, DWORD mask) {
+ DWORD attributes = GetFileAttributesW((WCHAR*)path->data);
+
+ if(attributes == INVALID_FILE_ATTRIBUTES) {
+ return 0;
+ }
+
+ return !!((attributes & mask) == mask);
+}
+
+static int is_ignored_name(int name_length, const WCHAR *name) {
+ if(name_length == 1 && name[0] == L'.') {
+ return 1;
+ } else if(name_length == 2 && !sys_memcmp(name, L"..", 2 * sizeof(WCHAR))) {
+ return 1;
+ }
+
+ return 0;
+}
+
+static int get_drive_number(const efile_path_t *path) {
+ const WCHAR *path_start;
+ int length;
+
+ ASSERT_PATH_FORMAT(path);
+
+ path_start = (WCHAR*)path->data + LP_PREFIX_LENGTH;
+ length = PATH_LENGTH(path) - LP_PREFIX_LENGTH;
+
+ if(length >= 2 && path_start[1] == L':') {
+ WCHAR drive_letter = path_start[0];
+
+ if(drive_letter >= L'A' && drive_letter <= L'Z') {
+ return drive_letter - L'A' + 1;
+ } else if(drive_letter >= L'a' && drive_letter <= L'z') {
+ return drive_letter - L'a' + 1;
+ }
+ }
+
+ return -1;
+}
+
+/* @brief Checks whether two *paths* are on the same mount point; they don't
+ * have to refer to existing or accessible files/directories. */
+static int has_same_mount_point(const efile_path_t *path_a, const efile_path_t *path_b) {
+ WCHAR *mount_a, *mount_b;
+ int result = 0;
+
+ mount_a = enif_alloc(path_a->size);
+ mount_b = enif_alloc(path_b->size);
+
+ if(mount_a != NULL && mount_b != NULL) {
+ int length_a, length_b;
+
+ length_a = PATH_LENGTH(path_a);
+ length_b = PATH_LENGTH(path_b);
+
+ if(GetVolumePathNameW((WCHAR*)path_a->data, mount_a, length_a)) {
+ ASSERT(wcslen(mount_a) <= length_a);
+
+ if(GetVolumePathNameW((WCHAR*)path_b->data, mount_b, length_b)) {
+ ASSERT(wcslen(mount_b) <= length_b);
+
+ result = !_wcsicmp(mount_a, mount_b);
+ }
+ }
+ }
+
+ if(mount_b != NULL) {
+ enif_free(mount_b);
+ }
+
+ if(mount_a != NULL) {
+ enif_free(mount_a);
+ }
+
+ return result;
+}
+
+/* Mirrors the PathIsRootW function of the shell API, but doesn't choke on
+ * paths longer than MAX_PATH. */
+static int is_path_root(const efile_path_t *path) {
+ const WCHAR *path_start, *path_end, *path_iterator;
+ int length;
+
+ ASSERT_PATH_FORMAT(path);
+
+ if(!IS_LONG_UNC_PATH(PATH_LENGTH(path), path->data)) {
+ path_start = (WCHAR*)path->data + LP_PREFIX_LENGTH;
+ length = PATH_LENGTH(path) - LP_PREFIX_LENGTH;
+
+ /* A single \ refers to the root of the current working directory. */
+ if(length == 1) {
+ return IS_SLASH(path_start[0]);
+ }
+
+ /* Drive letter. */
+ if(length == 3 && iswalpha(path_start[0]) && path_start[1] == L':') {
+ return IS_SLASH(path_start[2]);
+ }
+
+ return 0;
+ }
+
+ /* Check whether we're a UNC root, eg. \\server, \\server\share */
+
+ path_start = (WCHAR*)path->data + LP_UNC_PREFIX_LENGTH;
+ length = PATH_LENGTH(path) - LP_UNC_PREFIX_LENGTH;
+
+ path_end = &path_start[length];
+ path_iterator = path_start;
+
+ /* Server name must be at least one character. */
+ if(length <= 1) {
+ return 0;
+ }
+
+ /* Slide to the slash between the server and share names, if present. */
+ while(path_iterator < path_end && !IS_SLASH(*path_iterator)) {
+ path_iterator++;
+ }
+
+ /* Slide past the end of the string, stopping at the first slash we
+ * encounter. */
+ do {
+ path_iterator++;
+ } while(path_iterator < path_end && !IS_SLASH(*path_iterator));
+
+ /* If we're past the end of the string and it didnt't end with a slash,
+ * then we're a root path. */
+ return path_iterator >= path_end && !IS_SLASH(path_start[length - 1]);
+}
+
+posix_errno_t efile_open(const efile_path_t *path, enum efile_modes_t modes,
+ ErlNifResourceType *nif_type, efile_data_t **d) {
+
+ DWORD attributes, access_flags, open_mode;
+ HANDLE handle;
+
+ ASSERT_PATH_FORMAT(path);
+
+ access_flags = 0;
+ open_mode = 0;
+
+ if(modes & EFILE_MODE_READ && !(modes & EFILE_MODE_WRITE)) {
+ access_flags = GENERIC_READ;
+ open_mode = OPEN_EXISTING;
+ } else if(modes & EFILE_MODE_WRITE && !(modes & EFILE_MODE_READ)) {
+ access_flags = GENERIC_WRITE;
+ open_mode = CREATE_ALWAYS;
+ } else if(modes & EFILE_MODE_READ_WRITE) {
+ access_flags = GENERIC_READ | GENERIC_WRITE;
+ open_mode = OPEN_ALWAYS;
+ } else {
+ return EINVAL;
+ }
+
+ if(modes & EFILE_MODE_APPEND) {
+ access_flags |= FILE_APPEND_DATA;
+ open_mode = OPEN_ALWAYS;
+ }
+
+ if(modes & EFILE_MODE_EXCLUSIVE) {
+ open_mode = CREATE_NEW;
+ }
+
+ if(modes & EFILE_MODE_SYNC) {
+ attributes = FILE_FLAG_WRITE_THROUGH;
+ } else {
+ attributes = FILE_ATTRIBUTE_NORMAL;
+ }
+
+ handle = CreateFileW((WCHAR*)path->data, access_flags,
+ FILE_SHARE_FLAGS, NULL, open_mode, attributes, NULL);
+
+ if(handle != INVALID_HANDLE_VALUE) {
+ efile_win_t *w;
+
+ w = (efile_win_t*)enif_alloc_resource(nif_type, sizeof(efile_win_t));
+ w->handle = handle;
+
+ EFILE_INIT_RESOURCE(&w->common, modes);
+ (*d) = &w->common;
+
+ return 0;
+ } else {
+ DWORD last_error = GetLastError();
+
+ /* Rewrite all failures on directories to EISDIR to match the old
+ * driver. */
+ if(has_file_attributes(path, FILE_ATTRIBUTE_DIRECTORY)) {
+ return EISDIR;
+ }
+
+ return windows_to_posix_errno(last_error);
+ }
+}
+
+int efile_close(efile_data_t *d, posix_errno_t *error) {
+ efile_win_t *w = (efile_win_t*)d;
+ HANDLE handle;
+
+ ASSERT(enif_thread_type() == ERL_NIF_THR_DIRTY_IO_SCHEDULER);
+ ASSERT(erts_atomic32_read_nob(&d->state) == EFILE_STATE_CLOSED);
+ ASSERT(w->handle != INVALID_HANDLE_VALUE);
+
+ handle = w->handle;
+ w->handle = INVALID_HANDLE_VALUE;
+
+ enif_release_resource(d);
+
+ if(!CloseHandle(handle)) {
+ *error = windows_to_posix_errno(GetLastError());
+ return 0;
+ }
+
+ return 1;
+}
+
+static void shift_overlapped(OVERLAPPED *overlapped, DWORD shift) {
+ LARGE_INTEGER offset;
+
+ ASSERT(shift >= 0);
+
+ offset.HighPart = overlapped->OffsetHigh;
+ offset.LowPart = overlapped->Offset;
+
+ /* ~(Uint64)0 is a magic value ("append to end of file") which needs to be
+ * preserved. Other positions resulting in overflow would have errored out
+ * just prior to this point. */
+ if(offset.QuadPart != ERTS_UINT64_MAX) {
+ offset.QuadPart += shift;
+ }
+
+ /* All unused fields must be zeroed for the next call. */
+ sys_memset(overlapped, 0, sizeof(*overlapped));
+ overlapped->OffsetHigh = offset.HighPart;
+ overlapped->Offset = offset.LowPart;
+}
+
+static void shift_iov(SysIOVec **iov, int *iovlen, DWORD shift) {
+ SysIOVec *head_vec = (*iov);
+
+ ASSERT(shift >= 0);
+
+ while(shift > 0) {
+ ASSERT(head_vec < &(*iov)[*iovlen]);
+
+ if(shift < head_vec->iov_len) {
+ head_vec->iov_base = (char*)head_vec->iov_base + shift;
+ head_vec->iov_len -= shift;
+ break;
+ } else {
+ shift -= head_vec->iov_len;
+ head_vec++;
+ }
+ }
+
+ (*iovlen) -= head_vec - (*iov);
+ (*iov) = head_vec;
+}
+
+typedef BOOL (WINAPI *io_op_t)(HANDLE, LPVOID, DWORD, LPDWORD, LPOVERLAPPED);
+
+static Sint64 internal_sync_io(efile_win_t *w, io_op_t operation,
+ SysIOVec *iov, int iovlen, OVERLAPPED *overlapped) {
+
+ Sint64 bytes_processed = 0;
+
+ for(;;) {
+ DWORD block_bytes_processed, last_error;
+ BOOL succeeded;
+
+ if(iovlen < 1) {
+ return bytes_processed;
+ }
+
+ succeeded = operation(w->handle, iov->iov_base, iov->iov_len,
+ &block_bytes_processed, overlapped);
+ last_error = GetLastError();
+
+ if(!succeeded && (last_error != ERROR_HANDLE_EOF)) {
+ w->common.posix_errno = windows_to_posix_errno(last_error);
+ return -1;
+ } else if(block_bytes_processed == 0) {
+ /* EOF */
+ return bytes_processed;
+ }
+
+ if(overlapped != NULL) {
+ shift_overlapped(overlapped, block_bytes_processed);
+ }
+
+ shift_iov(&iov, &iovlen, block_bytes_processed);
+
+ bytes_processed += block_bytes_processed;
+ }
+}
+
+Sint64 efile_readv(efile_data_t *d, SysIOVec *iov, int iovlen) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ return internal_sync_io(w, ReadFile, iov, iovlen, NULL);
+}
+
+Sint64 efile_writev(efile_data_t *d, SysIOVec *iov, int iovlen) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ OVERLAPPED __overlapped, *overlapped;
+ Uint64 bytes_written;
+
+ if(w->common.modes & EFILE_MODE_APPEND) {
+ overlapped = &__overlapped;
+
+ sys_memset(overlapped, 0, sizeof(*overlapped));
+ overlapped->OffsetHigh = 0xFFFFFFFF;
+ overlapped->Offset = 0xFFFFFFFF;
+ } else {
+ overlapped = NULL;
+ }
+
+ return internal_sync_io(w, WriteFile, iov, iovlen, overlapped);
+}
+
+Sint64 efile_preadv(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ OVERLAPPED overlapped;
+
+ sys_memset(&overlapped, 0, sizeof(overlapped));
+ overlapped.OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
+ overlapped.Offset = offset & 0xFFFFFFFF;
+
+ return internal_sync_io(w, ReadFile, iov, iovlen, &overlapped);
+}
+
+Sint64 efile_pwritev(efile_data_t *d, Sint64 offset, SysIOVec *iov, int iovlen) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ OVERLAPPED overlapped;
+
+ sys_memset(&overlapped, 0, sizeof(overlapped));
+ overlapped.OffsetHigh = (offset >> 32) & 0xFFFFFFFF;
+ overlapped.Offset = offset & 0xFFFFFFFF;
+
+ return internal_sync_io(w, WriteFile, iov, iovlen, &overlapped);
+}
+
+int efile_seek(efile_data_t *d, enum efile_seek_t seek, Sint64 offset, Sint64 *new_position) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ LARGE_INTEGER large_offset, large_new_position;
+ DWORD whence;
+
+ switch(seek) {
+ case EFILE_SEEK_BOF: whence = FILE_BEGIN; break;
+ case EFILE_SEEK_CUR: whence = FILE_CURRENT; break;
+ case EFILE_SEEK_EOF: whence = FILE_END; break;
+ default: ERTS_INTERNAL_ERROR("Invalid seek parameter");
+ }
+
+ large_offset.QuadPart = offset;
+
+ if(!SetFilePointerEx(w->handle, large_offset, &large_new_position, whence)) {
+ w->common.posix_errno = windows_to_posix_errno(GetLastError());
+ return 0;
+ }
+
+ (*new_position) = large_new_position.QuadPart;
+
+ return 1;
+}
+
+int efile_sync(efile_data_t *d, int data_only) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ /* Windows doesn't support data-only syncing. */
+ (void)data_only;
+
+ if(!FlushFileBuffers(w->handle)) {
+ w->common.posix_errno = windows_to_posix_errno(GetLastError());
+ return 0;
+ }
+
+ return 1;
+}
+
+int efile_advise(efile_data_t *d, Sint64 offset, Sint64 length, enum efile_advise_t advise) {
+ /* Windows doesn't support this, but we'll pretend it does since the call
+ * is only a recommendation even on systems that do support it. */
+
+ (void)d;
+ (void)offset;
+ (void)length;
+ (void)advise;
+
+ return 1;
+}
+
+int efile_allocate(efile_data_t *d, Sint64 offset, Sint64 length) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ (void)d;
+ (void)offset;
+ (void)length;
+
+ w->common.posix_errno = ENOTSUP;
+
+ return 0;
+}
+
+int efile_truncate(efile_data_t *d) {
+ efile_win_t *w = (efile_win_t*)d;
+
+ if(!SetEndOfFile(w->handle)) {
+ w->common.posix_errno = windows_to_posix_errno(GetLastError());
+ return 0;
+ }
+
+ return 1;
+}
+
+static int is_executable_file(const efile_path_t *path) {
+ /* We're using the file extension in order to be quirks-compliant with the
+ * old driver, which never bothered to check the actual permissions. We
+ * could easily do so now (cf. GetNamedSecurityInfo) but the execute
+ * permission is only relevant for files that are started with the default
+ * loader, and batch files run just fine with read permission alone. */
+
+ int length = PATH_LENGTH(path);
+
+ if(length >= 4) {
+ const WCHAR *last_four = &((WCHAR*)path->data)[length - 4];
+
+ if (!_wcsicmp(last_four, L".exe") ||
+ !_wcsicmp(last_four, L".cmd") ||
+ !_wcsicmp(last_four, L".bat") ||
+ !_wcsicmp(last_four, L".com")) {
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+/* Returns whether the path refers to a link-like object, e.g. a junction
+ * point, symbolic link, or mounted folder. */
+static int is_name_surrogate(const efile_path_t *path) {
+ HANDLE handle;
+ int result;
+
+ handle = CreateFileW((const WCHAR*)path->data, GENERIC_READ,
+ FILE_SHARE_FLAGS, NULL, OPEN_EXISTING,
+ FILE_FLAG_OPEN_REPARSE_POINT |
+ FILE_FLAG_BACKUP_SEMANTICS,
+ NULL);
+ result = 0;
+
+ if(handle != INVALID_HANDLE_VALUE) {
+ REPARSE_GUID_DATA_BUFFER reparse_buffer;
+ DWORD unused_length;
+ BOOL success;
+
+ success = DeviceIoControl(handle,
+ FSCTL_GET_REPARSE_POINT, NULL, 0,
+ &reparse_buffer, sizeof(reparse_buffer),
+ &unused_length, NULL);
+
+ /* ERROR_MORE_DATA is tolerated since we're guaranteed to have filled
+ * the field we want. */
+ if(success || GetLastError() == ERROR_MORE_DATA) {
+ result = IsReparseTagNameSurrogate(reparse_buffer.ReparseTag);
+ }
+
+ CloseHandle(handle);
+ }
+
+ return result;
+}
+
+posix_errno_t efile_read_info(const efile_path_t *path, int follow_links, efile_fileinfo_t *result) {
+ BY_HANDLE_FILE_INFORMATION native_file_info;
+ DWORD attributes;
+ int is_link;
+
+ sys_memset(&native_file_info, 0, sizeof(native_file_info));
+ is_link = 0;
+
+ attributes = GetFileAttributesW((WCHAR*)path->data);
+
+ if(attributes == INVALID_FILE_ATTRIBUTES) {
+ DWORD last_error = GetLastError();
+
+ /* Querying a network share root fails with ERROR_BAD_NETPATH, so we'll
+ * fake it as a directory just like local roots. */
+ if(!is_path_root(path) || last_error != ERROR_BAD_NETPATH) {
+ return windows_to_posix_errno(last_error);
+ }
+
+ attributes = FILE_ATTRIBUTE_DIRECTORY;
+ } else if(is_path_root(path)) {
+ /* Local (or mounted) roots can be queried with GetFileAttributesW but
+ * lack support for GetFileInformationByHandle, so we'll skip that
+ * part. */
+ } else {
+ HANDLE handle;
+
+ if(attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
+ is_link = is_name_surrogate(path);
+ }
+
+ if(follow_links && is_link) {
+ posix_errno_t posix_errno;
+ efile_path_t resolved_path;
+
+ posix_errno = internal_read_link(path, &resolved_path);
+
+ if(posix_errno != 0) {
+ return posix_errno;
+ }
+
+ return efile_read_info(&resolved_path, 0, result);
+ }
+
+ handle = CreateFileW((const WCHAR*)path->data, GENERIC_READ,
+ FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS,
+ NULL);
+
+ /* The old driver never cared whether this succeeded. */
+ if(handle != INVALID_HANDLE_VALUE) {
+ GetFileInformationByHandle(handle, &native_file_info);
+ CloseHandle(handle);
+ }
+
+ FILETIME_TO_EPOCH(result->m_time, native_file_info.ftLastWriteTime);
+ FILETIME_TO_EPOCH(result->a_time, native_file_info.ftLastAccessTime);
+ FILETIME_TO_EPOCH(result->c_time, native_file_info.ftCreationTime);
+
+ if(result->m_time == -EPOCH_DIFFERENCE) {
+ /* Default to 1970 just like the old driver. */
+ result->m_time = 0;
+ }
+
+ if(result->a_time == -EPOCH_DIFFERENCE) {
+ result->a_time = result->m_time;
+ }
+
+ if(result->c_time == -EPOCH_DIFFERENCE) {
+ result->c_time = result->m_time;
+ }
+ }
+
+ if(is_link) {
+ result->type = EFILE_FILETYPE_SYMLINK;
+ /* This should be _S_IFLNK, but the old driver always set
+ * non-directories to _S_IFREG. */
+ result->mode |= _S_IFREG;
+ } else if(attributes & FILE_ATTRIBUTE_DIRECTORY) {
+ result->type = EFILE_FILETYPE_DIRECTORY;
+ result->mode |= _S_IFDIR | _S_IEXEC;
+ } else {
+ if(is_executable_file(path)) {
+ result->mode |= _S_IEXEC;
+ }
+
+ result->type = EFILE_FILETYPE_REGULAR;
+ result->mode |= _S_IFREG;
+ }
+
+ if(!(attributes & FILE_ATTRIBUTE_READONLY)) {
+ result->access = EFILE_ACCESS_READ | EFILE_ACCESS_WRITE;
+ result->mode |= _S_IREAD | _S_IWRITE;
+ } else {
+ result->access = EFILE_ACCESS_READ;
+ result->mode |= _S_IREAD;
+ }
+
+ /* Propagate user mode-bits to group/other fields */
+ result->mode |= (result->mode & 0700) >> 3;
+ result->mode |= (result->mode & 0700) >> 6;
+
+ result->size =
+ ((Uint64)native_file_info.nFileSizeHigh << 32ull) |
+ (Uint64)native_file_info.nFileSizeLow;
+
+ result->links = MAX(1, native_file_info.nNumberOfLinks);
+
+ result->major_device = get_drive_number(path);
+ result->minor_device = 0;
+ result->inode = 0;
+ result->uid = 0;
+ result->gid = 0;
+
+ return 0;
+}
+
+posix_errno_t efile_set_permissions(const efile_path_t *path, Uint32 permissions) {
+ DWORD attributes = GetFileAttributesW((WCHAR*)path->data);
+
+ if(attributes == INVALID_FILE_ATTRIBUTES) {
+ return windows_to_posix_errno(GetLastError());
+ }
+
+ if(permissions & _S_IWRITE) {
+ attributes &= ~FILE_ATTRIBUTE_READONLY;
+ } else {
+ attributes |= FILE_ATTRIBUTE_READONLY;
+ }
+
+ if(SetFileAttributesW((WCHAR*)path->data, attributes)) {
+ return 0;
+ }
+
+ return windows_to_posix_errno(GetLastError());
+}
+
+posix_errno_t efile_set_owner(const efile_path_t *path, Sint32 owner, Sint32 group) {
+ (void)path;
+ (void)owner;
+ (void)group;
+
+ return 0;
+}
+
+posix_errno_t efile_set_time(const efile_path_t *path, Sint64 a_time, Sint64 m_time, Sint64 c_time) {
+ FILETIME accessed, modified, created;
+ DWORD last_error, attributes;
+ HANDLE handle;
+
+ attributes = GetFileAttributesW((WCHAR*)path->data);
+
+ if(attributes == INVALID_FILE_ATTRIBUTES) {
+ return windows_to_posix_errno(GetLastError());
+ }
+
+ /* If the file is read-only, we have to make it temporarily writable while
+ * setting new metadata. */
+ if(attributes & FILE_ATTRIBUTE_READONLY) {
+ DWORD without_readonly = attributes & ~FILE_ATTRIBUTE_READONLY;
+
+ if(!SetFileAttributesW((WCHAR*)path->data, without_readonly)) {
+ return windows_to_posix_errno(GetLastError());
+ }
+ }
+
+ EPOCH_TO_FILETIME(modified, m_time);
+ EPOCH_TO_FILETIME(accessed, a_time);
+ EPOCH_TO_FILETIME(created, c_time);
+
+ handle = CreateFileW((WCHAR*)path->data, GENERIC_READ | GENERIC_WRITE,
+ FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+ last_error = GetLastError();
+
+ if(handle != INVALID_HANDLE_VALUE) {
+ if(SetFileTime(handle, &created, &accessed, &modified)) {
+ last_error = ERROR_SUCCESS;
+ } else {
+ last_error = GetLastError();
+ }
+
+ CloseHandle(handle);
+ }
+
+ if(attributes & FILE_ATTRIBUTE_READONLY) {
+ SetFileAttributesW((WCHAR*)path->data, attributes);
+ }
+
+ return windows_to_posix_errno(last_error);
+}
+
+static posix_errno_t internal_read_link(const efile_path_t *path, efile_path_t *result) {
+ DWORD required_length, actual_length;
+ HANDLE link_handle;
+ DWORD last_error;
+
+ link_handle = CreateFileW((WCHAR*)path->data, GENERIC_READ,
+ FILE_SHARE_FLAGS, NULL, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+ last_error = GetLastError();
+
+ if(link_handle == INVALID_HANDLE_VALUE) {
+ return windows_to_posix_errno(last_error);
+ }
+
+ required_length = GetFinalPathNameByHandleW(link_handle, NULL, 0, 0);
+ last_error = GetLastError();
+
+ if(required_length <= 0) {
+ CloseHandle(link_handle);
+ return windows_to_posix_errno(last_error);
+ }
+
+ /* Unlike many other path functions (eg. GetFullPathNameW), this one
+ * includes the NUL terminator in its required length. */
+ if(!enif_alloc_binary(required_length * sizeof(WCHAR), result)) {
+ CloseHandle(link_handle);
+ return ENOMEM;
+ }
+
+ actual_length = GetFinalPathNameByHandleW(link_handle,
+ (WCHAR*)result->data, required_length, 0);
+ last_error = GetLastError();
+
+ CloseHandle(link_handle);
+
+ if(actual_length == 0 || actual_length >= required_length) {
+ enif_release_binary(result);
+ return windows_to_posix_errno(last_error);
+ }
+
+ /* GetFinalPathNameByHandle always prepends with "\\?\" and NUL-terminates,
+ * so we never have to touch-up the resulting path. */
+
+ ASSERT_PATH_FORMAT(result);
+
+ return 0;
+}
+
+posix_errno_t efile_read_link(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+ posix_errno_t posix_errno;
+ ErlNifBinary result_bin;
+ DWORD attributes;
+
+ ASSERT_PATH_FORMAT(path);
+
+ attributes = GetFileAttributesW((WCHAR*)path->data);
+
+ if(attributes == INVALID_FILE_ATTRIBUTES) {
+ return windows_to_posix_errno(GetLastError());
+ } else if(!(attributes & FILE_ATTRIBUTE_REPARSE_POINT)) {
+ return EINVAL;
+ }
+
+ if(!is_name_surrogate(path)) {
+ return EINVAL;
+ }
+
+ posix_errno = internal_read_link(path, &result_bin);
+
+ if(posix_errno == 0) {
+ if(!normalize_path_result(&result_bin)) {
+ enif_release_binary(&result_bin);
+ return ENOMEM;
+ }
+
+ (*result) = enif_make_binary(env, &result_bin);
+ }
+
+ return posix_errno;
+}
+
+posix_errno_t efile_list_dir(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+ ERL_NIF_TERM list_head;
+ WIN32_FIND_DATAW data;
+ HANDLE search_handle;
+ WCHAR *search_path;
+ DWORD last_error;
+
+ ASSERT_PATH_FORMAT(path);
+
+ search_path = enif_alloc(path->size + 2 * sizeof(WCHAR));
+
+ if(search_path == NULL) {
+ return ENOMEM;
+ }
+
+ sys_memcpy(search_path, path->data, path->size);
+ search_path[PATH_LENGTH(path) + 0] = L'\\';
+ search_path[PATH_LENGTH(path) + 1] = L'*';
+ search_path[PATH_LENGTH(path) + 2] = L'\0';
+
+ search_handle = FindFirstFileW(search_path, &data);
+ last_error = GetLastError();
+
+ enif_free(search_path);
+
+ if(search_handle == INVALID_HANDLE_VALUE) {
+ return windows_to_posix_errno(last_error);
+ }
+
+ list_head = enif_make_list(env, 0);
+
+ do {
+ int name_length = wcslen(data.cFileName);
+
+ if(!is_ignored_name(name_length, data.cFileName)) {
+ unsigned char *name_bytes;
+ ERL_NIF_TERM name_term;
+ size_t name_size;
+
+ name_size = name_length * sizeof(WCHAR);
+
+ name_bytes = enif_make_new_binary(env, name_size, &name_term);
+ sys_memcpy(name_bytes, data.cFileName, name_size);
+
+ list_head = enif_make_list_cell(env, name_term, list_head);
+ }
+ } while(FindNextFileW(search_handle, &data));
+
+ FindClose(search_handle);
+ (*result) = list_head;
+
+ return 0;
+}
+
+posix_errno_t efile_rename(const efile_path_t *old_path, const efile_path_t *new_path) {
+ BOOL old_is_directory, new_is_directory;
+ DWORD move_flags, last_error;
+
+ ASSERT_PATH_FORMAT(old_path);
+ ASSERT_PATH_FORMAT(new_path);
+
+ move_flags = MOVEFILE_COPY_ALLOWED | MOVEFILE_WRITE_THROUGH;
+
+ if(MoveFileExW((WCHAR*)old_path->data, (WCHAR*)new_path->data, move_flags)) {
+ return 0;
+ }
+
+ last_error = GetLastError();
+
+ old_is_directory = has_file_attributes(old_path, FILE_ATTRIBUTE_DIRECTORY);
+ new_is_directory = has_file_attributes(new_path, FILE_ATTRIBUTE_DIRECTORY);
+
+ switch(last_error) {
+ case ERROR_SHARING_VIOLATION:
+ case ERROR_ACCESS_DENIED:
+ if(old_is_directory) {
+ BOOL moved_into_itself;
+
+ moved_into_itself = (old_path->size <= new_path->size) &&
+ !_wcsnicmp((WCHAR*)old_path->data, (WCHAR*)new_path->data,
+ PATH_LENGTH(old_path));
+
+ if(moved_into_itself) {
+ return EINVAL;
+ } else if(is_path_root(old_path)) {
+ return EINVAL;
+ }
+
+ /* Renaming a directory across volumes needs to be rewritten as
+ * EXDEV so that the caller can respond by simulating it with
+ * copy/delete operations.
+ *
+ * Files are handled through MOVEFILE_COPY_ALLOWED. */
+ if(!has_same_mount_point(old_path, new_path)) {
+ return EXDEV;
+ }
+ }
+ break;
+ case ERROR_PATH_NOT_FOUND:
+ case ERROR_FILE_NOT_FOUND:
+ return ENOENT;
+ case ERROR_ALREADY_EXISTS:
+ case ERROR_FILE_EXISTS:
+ if(old_is_directory && !new_is_directory) {
+ return ENOTDIR;
+ } else if(!old_is_directory && new_is_directory) {
+ return EISDIR;
+ } else if(old_is_directory && new_is_directory) {
+ /* This will fail if the destination isn't empty. */
+ if(RemoveDirectoryW((WCHAR*)new_path->data)) {
+ return efile_rename(old_path, new_path);
+ }
+
+ return EEXIST;
+ } else if(!old_is_directory && !new_is_directory) {
+ /* This is pretty iffy; the public documentation says that the
+ * operation may EACCES on some systems when either file is open,
+ * which gives us room to use MOVEFILE_REPLACE_EXISTING and be done
+ * with it, but the old implementation simulated Unix semantics and
+ * there's a lot of code that relies on that.
+ *
+ * The simulation renames the destination to a scratch name to get
+ * around the fact that it's impossible to open (and by extension
+ * rename) a file that's been deleted while open. It has a few
+ * drawbacks though;
+ *
+ * 1) It's not atomic as there's a small window where there's no
+ * file at all on the destination path.
+ * 2) It will confuse applications that subscribe to folder
+ * changes.
+ * 3) It will fail if we lack general permission to write in the
+ * same folder. */
+
+ WCHAR *swap_path = enif_alloc(new_path->size + sizeof(WCHAR) * 64);
+
+ if(swap_path == NULL) {
+ return ENOMEM;
+ } else {
+ static LONGLONG unique_counter = 0;
+ WCHAR *swap_path_end;
+
+ /* We swap in the same folder as the destination to be
+ * reasonably sure that it's on the same volume. Note that
+ * we're avoiding GetTempFileNameW as it will fail on long
+ * paths. */
+
+ sys_memcpy(swap_path, (WCHAR*)new_path->data, new_path->size);
+ swap_path_end = swap_path + PATH_LENGTH(new_path);
+
+ while(!IS_SLASH(*swap_path_end)) {
+ ASSERT(swap_path_end > swap_path);
+ swap_path_end--;
+ }
+
+ StringCchPrintfW(&swap_path_end[1], 64, L"erl-%lx-%llx.tmp",
+ GetCurrentProcessId(), unique_counter);
+ InterlockedIncrement64(&unique_counter);
+ }
+
+ if(MoveFileExW((WCHAR*)new_path->data, swap_path, MOVEFILE_REPLACE_EXISTING)) {
+ if(MoveFileExW((WCHAR*)old_path->data, (WCHAR*)new_path->data, move_flags)) {
+ last_error = ERROR_SUCCESS;
+ DeleteFileW(swap_path);
+ } else {
+ last_error = GetLastError();
+ MoveFileW(swap_path, (WCHAR*)new_path->data);
+ }
+ } else {
+ last_error = GetLastError();
+ DeleteFileW(swap_path);
+ }
+
+ enif_free(swap_path);
+
+ return windows_to_posix_errno(last_error);
+ }
+
+ return EEXIST;
+ }
+
+ return windows_to_posix_errno(last_error);
+}
+
+posix_errno_t efile_make_hard_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+ ASSERT_PATH_FORMAT(existing_path);
+ ASSERT_PATH_FORMAT(new_path);
+
+ if(!CreateHardLinkW((WCHAR*)new_path->data, (WCHAR*)existing_path->data, NULL)) {
+ return windows_to_posix_errno(GetLastError());
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_make_soft_link(const efile_path_t *existing_path, const efile_path_t *new_path) {
+ DWORD link_flags;
+
+ ASSERT_PATH_FORMAT(existing_path);
+ ASSERT_PATH_FORMAT(new_path);
+
+ if(has_file_attributes(existing_path, FILE_ATTRIBUTE_DIRECTORY)) {
+ link_flags = SYMBOLIC_LINK_FLAG_DIRECTORY;
+ } else {
+ link_flags = 0;
+ }
+
+ if(!CreateSymbolicLinkW((WCHAR*)new_path->data, (WCHAR*)existing_path->data, link_flags)) {
+ return windows_to_posix_errno(GetLastError());
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_make_dir(const efile_path_t *path) {
+ ASSERT_PATH_FORMAT(path);
+
+ if(!CreateDirectoryW((WCHAR*)path->data, NULL)) {
+ return windows_to_posix_errno(GetLastError());
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_del_file(const efile_path_t *path) {
+ ASSERT_PATH_FORMAT(path);
+
+ if(!DeleteFileW((WCHAR*)path->data)) {
+ DWORD last_error = GetLastError();
+
+ switch(last_error) {
+ case ERROR_INVALID_NAME:
+ /* Attempted to delete a device or similar. */
+ return EACCES;
+ case ERROR_ACCESS_DENIED:
+ /* Windows NT reports removing a directory as EACCES instead of
+ * EPERM. */
+ if(has_file_attributes(path, FILE_ATTRIBUTE_DIRECTORY)) {
+ return EPERM;
+ }
+ break;
+ }
+
+ return windows_to_posix_errno(last_error);
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_del_dir(const efile_path_t *path) {
+ ASSERT_PATH_FORMAT(path);
+
+ if(!RemoveDirectoryW((WCHAR*)path->data)) {
+ DWORD last_error = GetLastError();
+
+ if(last_error == ERROR_DIRECTORY) {
+ return ENOTDIR;
+ }
+
+ return windows_to_posix_errno(last_error);
+ }
+
+ return 0;
+}
+
+posix_errno_t efile_set_cwd(const efile_path_t *path) {
+ const WCHAR *path_start;
+
+ ASSERT_PATH_FORMAT(path);
+
+ /* We have to use _wchdir since that's the only function that updates the
+ * per-drive working directory, but it naively assumes that all paths
+ * starting with \\ are UNC paths, so we have to skip the long-path prefix.
+ *
+ * _wchdir doesn't handle long-prefixed UNC paths either so we hand those
+ * to SetCurrentDirectoryW instead. The per-drive working directory is
+ * irrelevant for such paths anyway. */
+
+ if(!IS_LONG_UNC_PATH(PATH_LENGTH(path), path->data)) {
+ path_start = (WCHAR*)path->data + LP_PREFIX_LENGTH;
+
+ if(_wchdir(path_start)) {
+ return windows_to_posix_errno(GetLastError());
+ }
+ } else {
+ if(!SetCurrentDirectoryW((WCHAR*)path->data)) {
+ return windows_to_posix_errno(GetLastError());
+ }
+ }
+
+ return 0;
+}
+
+static int is_valid_drive(int device_index) {
+ WCHAR drive_path[4] = {L'?', L':', L'\\', L'\0'};
+
+ if(device_index == 0) {
+ /* Default drive; always valid. */
+ return 1;
+ } else if(device_index > (L'Z' - L'A' + 1)) {
+ return 0;
+ }
+
+ drive_path[0] = device_index + L'A' - 1;
+
+ switch(GetDriveTypeW(drive_path)) {
+ case DRIVE_NO_ROOT_DIR:
+ case DRIVE_UNKNOWN:
+ return 0;
+ }
+
+ return 1;
+}
+
+posix_errno_t efile_get_device_cwd(ErlNifEnv *env, int device_index, ERL_NIF_TERM *result) {
+ ErlNifBinary result_bin;
+
+ /* _wgetdcwd might crash the entire emulator on debug builds since the CRT
+ * invalid parameter handler asserts if passed a non-existent drive (Or
+ * simply one that has been unmounted), so we check it ourselves to avoid
+ * that. */
+ if(!is_valid_drive(device_index)) {
+ return EACCES;
+ }
+
+ if(!enif_alloc_binary(MAX_PATH * sizeof(WCHAR), &result_bin)) {
+ return ENOMEM;
+ }
+
+ if(_wgetdcwd(device_index, (WCHAR*)result_bin.data, MAX_PATH) == NULL) {
+ enif_release_binary(&result_bin);
+ return EACCES;
+ }
+
+ if(!normalize_path_result(&result_bin)) {
+ enif_release_binary(&result_bin);
+ return ENOMEM;
+ }
+
+ (*result) = enif_make_binary(env, &result_bin);
+
+ return 0;
+}
+
+posix_errno_t efile_get_cwd(ErlNifEnv *env, ERL_NIF_TERM *result) {
+ return efile_get_device_cwd(env, 0, result);
+}
+
+posix_errno_t efile_altname(ErlNifEnv *env, const efile_path_t *path, ERL_NIF_TERM *result) {
+ ErlNifBinary result_bin;
+
+ ASSERT_PATH_FORMAT(path);
+
+ if(is_path_root(path)) {
+ /* Root paths can't be queried so we'll just return them as they are. */
+ if(!enif_alloc_binary(path->size, &result_bin)) {
+ return ENOMEM;
+ }
+
+ sys_memcpy(result_bin.data, path->data, path->size);
+ } else {
+ WIN32_FIND_DATAW data;
+ HANDLE handle;
+
+ WCHAR *name_buffer;
+ int name_length;
+
+ /* Reject path wildcards. */
+ if(wcspbrk(&((const WCHAR*)path->data)[LP_PREFIX_LENGTH], L"?*")) {
+ return ENOENT;
+ }
+
+ handle = FindFirstFileW((const WCHAR*)path->data, &data);
+
+ if(handle == INVALID_HANDLE_VALUE) {
+ return windows_to_posix_errno(GetLastError());
+ }
+
+ FindClose(handle);
+
+ name_length = wcslen(data.cAlternateFileName);
+
+ if(name_length > 0) {
+ name_buffer = data.cAlternateFileName;
+ } else {
+ name_length = wcslen(data.cFileName);
+ name_buffer = data.cFileName;
+ }
+
+ /* Include NUL-terminator; it will be removed after normalization. */
+ name_length += 1;
+
+ if(!enif_alloc_binary(name_length * sizeof(WCHAR), &result_bin)) {
+ return ENOMEM;
+ }
+
+ sys_memcpy(result_bin.data, name_buffer, name_length * sizeof(WCHAR));
+ }
+
+ if(!normalize_path_result(&result_bin)) {
+ enif_release_binary(&result_bin);
+ return ENOMEM;
+ }
+
+ (*result) = enif_make_binary(env, &result_bin);
+
+ return 0;
+}
+
+static int windows_to_posix_errno(DWORD last_error) {
+ switch(last_error) {
+ case ERROR_SUCCESS:
+ return 0;
+ case ERROR_INVALID_FUNCTION:
+ case ERROR_INVALID_DATA:
+ case ERROR_INVALID_PARAMETER:
+ case ERROR_INVALID_TARGET_HANDLE:
+ case ERROR_INVALID_CATEGORY:
+ case ERROR_NEGATIVE_SEEK:
+ return EINVAL;
+ case ERROR_DIR_NOT_EMPTY:
+ return EEXIST;
+ case ERROR_BAD_FORMAT:
+ return ENOEXEC;
+ case ERROR_PATH_NOT_FOUND:
+ case ERROR_FILE_NOT_FOUND:
+ case ERROR_NO_MORE_FILES:
+ case ERROR_INVALID_NAME:
+ return ENOENT;
+ case ERROR_TOO_MANY_OPEN_FILES:
+ return EMFILE;
+ case ERROR_ACCESS_DENIED:
+ case ERROR_INVALID_ACCESS:
+ case ERROR_CURRENT_DIRECTORY:
+ case ERROR_SHARING_VIOLATION:
+ case ERROR_LOCK_VIOLATION:
+ case ERROR_INVALID_PASSWORD:
+ case ERROR_DRIVE_LOCKED:
+ return EACCES;
+ case ERROR_INVALID_HANDLE:
+ return EBADF;
+ case ERROR_NOT_ENOUGH_MEMORY:
+ case ERROR_OUTOFMEMORY:
+ case ERROR_OUT_OF_STRUCTURES:
+ return ENOMEM;
+ case ERROR_INVALID_DRIVE:
+ case ERROR_BAD_UNIT:
+ case ERROR_NOT_READY:
+ case ERROR_REM_NOT_LIST:
+ case ERROR_DUP_NAME:
+ case ERROR_BAD_NETPATH:
+ case ERROR_NETWORK_BUSY:
+ case ERROR_DEV_NOT_EXIST:
+ case ERROR_BAD_NET_NAME:
+ return ENXIO;
+ case ERROR_NOT_SAME_DEVICE:
+ return EXDEV;
+ case ERROR_WRITE_PROTECT:
+ return EROFS;
+ case ERROR_BAD_LENGTH:
+ case ERROR_BUFFER_OVERFLOW:
+ return E2BIG;
+ case ERROR_SEEK:
+ case ERROR_SECTOR_NOT_FOUND:
+ return ESPIPE;
+ case ERROR_NOT_DOS_DISK:
+ return ENODEV;
+ case ERROR_GEN_FAILURE:
+ return ENODEV;
+ case ERROR_SHARING_BUFFER_EXCEEDED:
+ case ERROR_NO_MORE_SEARCH_HANDLES:
+ return EMFILE;
+ case ERROR_HANDLE_EOF:
+ case ERROR_BROKEN_PIPE:
+ return EPIPE;
+ case ERROR_HANDLE_DISK_FULL:
+ case ERROR_DISK_FULL:
+ return ENOSPC;
+ case ERROR_NOT_SUPPORTED:
+ return ENOTSUP;
+ case ERROR_FILE_EXISTS:
+ case ERROR_ALREADY_EXISTS:
+ case ERROR_CANNOT_MAKE:
+ return EEXIST;
+ case ERROR_ALREADY_ASSIGNED:
+ return EBUSY;
+ case ERROR_NO_PROC_SLOTS:
+ return EAGAIN;
+ case ERROR_CANT_RESOLVE_FILENAME:
+ return EMLINK;
+ case ERROR_PRIVILEGE_NOT_HELD:
+ return EPERM;
+ case ERROR_ARENA_TRASHED:
+ case ERROR_INVALID_BLOCK:
+ case ERROR_BAD_ENVIRONMENT:
+ case ERROR_BAD_COMMAND:
+ case ERROR_CRC:
+ case ERROR_OUT_OF_PAPER:
+ case ERROR_READ_FAULT:
+ case ERROR_WRITE_FAULT:
+ case ERROR_WRONG_DISK:
+ case ERROR_NET_WRITE_FAULT:
+ return EIO;
+ default: /* not to do with files I expect. */
+ return EIO;
+ }
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-06 07:39:30 +0000