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-rw-r--r--erts/emulator/sys/unix/sys_drivers.c1862
1 files changed, 1862 insertions, 0 deletions
diff --git a/erts/emulator/sys/unix/sys_drivers.c b/erts/emulator/sys/unix/sys_drivers.c
new file mode 100644
index 0000000000..2a7cd91265
--- /dev/null
+++ b/erts/emulator/sys/unix/sys_drivers.c
@@ -0,0 +1,1862 @@
+/*
+ * %CopyrightBegin%
+ *
+ * Copyright Ericsson AB 1996-2014. 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%
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#ifdef ISC32
+#define _POSIX_SOURCE
+#define _XOPEN_SOURCE
+#endif
+
+#include <sys/times.h> /* ! */
+#include <time.h>
+#include <signal.h>
+#include <sys/wait.h>
+#include <sys/uio.h>
+#include <termios.h>
+#include <ctype.h>
+#include <sys/utsname.h>
+#include <sys/select.h>
+#include <arpa/inet.h>
+
+#ifdef ISC32
+#include <sys/bsdtypes.h>
+#endif
+
+#include <termios.h>
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+
+#define WANT_NONBLOCKING /* must define this to pull in defs from sys.h */
+#include "sys.h"
+
+#ifdef USE_THREADS
+#include "erl_threads.h"
+#endif
+
+extern char **environ;
+extern erts_smp_rwmtx_t environ_rwmtx;
+
+extern erts_smp_atomic_t sys_misc_mem_sz;
+
+static Eterm forker_port;
+
+#define MAX_VSIZE 16 /* Max number of entries allowed in an I/O
+ * vector sock_sendv().
+ */
+/*
+ * Don't need global.h, but erl_cpu_topology.h won't compile otherwise
+ */
+#include "global.h"
+#include "erl_cpu_topology.h"
+
+#include "erl_sys_driver.h"
+#include "sys_uds.h"
+
+#include "erl_child_setup.h"
+
+#if defined IOV_MAX
+#define MAXIOV IOV_MAX
+#elif defined UIO_MAXIOV
+#define MAXIOV UIO_MAXIOV
+#else
+#define MAXIOV 16
+#endif
+
+#ifdef USE_THREADS
+# define FDBLOCK 1
+#else
+# define FDBLOCK 0
+#endif
+
+/* Used by the fd driver iff the fd could not be set to non-blocking */
+typedef struct ErtsSysBlocking_ {
+ ErlDrvPDL pdl;
+ int res;
+ int err;
+ unsigned int pkey;
+} ErtsSysBlocking;
+
+typedef struct fd_data {
+ int fd;
+ char pbuf[4]; /* hold partial packet bytes */
+ int psz; /* size of pbuf */
+ char *buf;
+ char *cpos;
+ int sz;
+ int remain; /* for input on fd */
+} ErtsSysFdData;
+
+typedef struct driver_data {
+ ErlDrvPort port_num;
+ ErtsSysFdData *ofd;
+ ErtsSysFdData *ifd;
+ int packet_bytes;
+ int pid;
+ int alive;
+ int status;
+ int terminating;
+ ErtsSysBlocking *blocking;
+} ErtsSysDriverData;
+
+#define DIR_SEPARATOR_CHAR '/'
+
+#if defined(__ANDROID__)
+#define SHELL "/system/bin/sh"
+#else
+#define SHELL "/bin/sh"
+#endif /* __ANDROID__ */
+
+#if defined(DEBUG)
+#define ERL_BUILD_TYPE_MARKER ".debug"
+#elif defined(PURIFY)
+#define ERL_BUILD_TYPE_MARKER ".purify"
+#elif defined(QUANTIFY)
+#define ERL_BUILD_TYPE_MARKER ".quantify"
+#elif defined(PURECOV)
+#define ERL_BUILD_TYPE_MARKER ".purecov"
+#elif defined(VALGRIND)
+#define ERL_BUILD_TYPE_MARKER ".valgrind"
+#else /* opt */
+#define ERL_BUILD_TYPE_MARKER
+#endif
+
+#ifdef DEBUG
+#define close(fd) do { int res = close(fd); ASSERT(res > -1); } while(0)
+#endif
+
+#define CHILD_SETUP_PROG_NAME "erl_child_setup" ERL_BUILD_TYPE_MARKER
+
+// #define HARD_DEBUG
+#ifdef HARD_DEBUG
+#define driver_select(port_num, fd, flags, onoff) \
+ do { \
+ if (((flags) & ERL_DRV_READ) && onoff) \
+ fprintf(stderr,"%010d %p: read select %d\r\n", __LINE__, port_num, (int)fd); \
+ if (((flags) & ERL_DRV_WRITE) && onoff) \
+ fprintf(stderr,"%010d %p: writ select %d\r\n", __LINE__, port_num, (int)fd); \
+ if (((flags) & ERL_DRV_READ) && !onoff) \
+ fprintf(stderr,"%010d %p: read unsele %d\r\n", __LINE__, port_num, (int)fd); \
+ if (((flags) & ERL_DRV_WRITE) && !onoff) \
+ fprintf(stderr,"%010d %p: writ unsele %d\r\n", __LINE__, port_num, (int)fd); \
+ driver_select_nkp(port_num, fd, flags, onoff); \
+ } while(0)
+#endif
+
+/*
+ * Decreasing the size of it below 16384 is not allowed.
+ */
+
+#define ERTS_SYS_READ_BUF_SZ (64*1024)
+
+/* I. Initialization */
+
+void
+erl_sys_late_init(void)
+{
+ SysDriverOpts opts;
+#ifdef ERTS_SMP
+ Port *port;
+#endif
+
+ sys_signal(SIGPIPE, SIG_IGN); /* Ignore - we'll handle the write failure */
+
+ opts.packet_bytes = 0;
+ opts.use_stdio = 1;
+ opts.redir_stderr = 0;
+ opts.read_write = 0;
+ opts.hide_window = 0;
+ opts.wd = NULL;
+ opts.envir = NULL;
+ opts.exit_status = 0;
+ opts.overlapped_io = 0;
+ opts.spawn_type = ERTS_SPAWN_ANY;
+ opts.argv = NULL;
+ opts.parallelism = erts_port_parallelism;
+
+#ifdef ERTS_SMP
+ port =
+#endif
+ erts_open_driver(&forker_driver, make_internal_pid(0), "forker", &opts, NULL, NULL);
+#ifdef ERTS_SMP
+ erts_mtx_unlock(port->lock);
+#endif
+}
+
+/* II. Prototypes */
+
+/* II.I Spawn prototypes */
+static ErlDrvData spawn_start(ErlDrvPort, char*, SysDriverOpts*);
+static ErlDrvSSizeT spawn_control(ErlDrvData, unsigned int, char *,
+ ErlDrvSizeT, char **, ErlDrvSizeT);
+
+/* II.II Vanilla prototypes */
+static ErlDrvData vanilla_start(ErlDrvPort, char*, SysDriverOpts*);
+
+
+/* II.III FD prototypes */
+static ErlDrvData fd_start(ErlDrvPort, char*, SysDriverOpts*);
+#if FDBLOCK
+static void fd_async(void *);
+static void fd_ready_async(ErlDrvData drv_data, ErlDrvThreadData thread_data);
+#endif
+static ErlDrvSSizeT fd_control(ErlDrvData, unsigned int, char *, ErlDrvSizeT,
+ char **, ErlDrvSizeT);
+static void fd_stop(ErlDrvData);
+static void fd_flush(ErlDrvData);
+
+/* II.IV Common prototypes */
+static void stop(ErlDrvData);
+static void ready_input(ErlDrvData, ErlDrvEvent);
+static void ready_output(ErlDrvData, ErlDrvEvent);
+static void output(ErlDrvData, char*, ErlDrvSizeT);
+static void outputv(ErlDrvData, ErlIOVec*);
+static void stop_select(ErlDrvEvent, void*);
+
+/* II.V Forker prototypes */
+static ErlDrvData forker_start(ErlDrvPort, char*, SysDriverOpts*);
+static void forker_stop(ErlDrvData);
+static void forker_ready_input(ErlDrvData, ErlDrvEvent);
+static void forker_ready_output(ErlDrvData, ErlDrvEvent);
+static ErlDrvSSizeT forker_control(ErlDrvData, unsigned int, char *,
+ ErlDrvSizeT, char **, ErlDrvSizeT);
+
+/* III Driver entries */
+
+/* III.I The spawn driver */
+struct erl_drv_entry spawn_driver_entry = {
+ NULL,
+ spawn_start,
+ stop,
+ output,
+ ready_input,
+ ready_output,
+ "spawn",
+ NULL,
+ NULL,
+ spawn_control,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ ERL_DRV_EXTENDED_MARKER,
+ ERL_DRV_EXTENDED_MAJOR_VERSION,
+ ERL_DRV_EXTENDED_MINOR_VERSION,
+ ERL_DRV_FLAG_USE_PORT_LOCKING | ERL_DRV_FLAG_USE_INIT_ACK,
+ NULL, NULL,
+ stop_select
+};
+
+/* III.II The fd driver */
+struct erl_drv_entry fd_driver_entry = {
+ NULL,
+ fd_start,
+ fd_stop,
+ output,
+ ready_input,
+ ready_output,
+ "fd",
+ NULL,
+ NULL,
+ fd_control,
+ NULL,
+ outputv,
+#if FDBLOCK
+ fd_ready_async, /* ready_async */
+#else
+ NULL,
+#endif
+ fd_flush, /* flush */
+ NULL, /* call */
+ NULL, /* event */
+ ERL_DRV_EXTENDED_MARKER,
+ ERL_DRV_EXTENDED_MAJOR_VERSION,
+ ERL_DRV_EXTENDED_MINOR_VERSION,
+ 0, /* ERL_DRV_FLAGs */
+ NULL, /* handle2 */
+ NULL, /* process_exit */
+ stop_select
+};
+
+/* III.III The vanilla driver */
+struct erl_drv_entry vanilla_driver_entry = {
+ NULL,
+ vanilla_start,
+ stop,
+ output,
+ ready_input,
+ ready_output,
+ "vanilla",
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL, /* flush */
+ NULL, /* call */
+ NULL, /* event */
+ ERL_DRV_EXTENDED_MARKER,
+ ERL_DRV_EXTENDED_MAJOR_VERSION,
+ ERL_DRV_EXTENDED_MINOR_VERSION,
+ 0, /* ERL_DRV_FLAGs */
+ NULL, /* handle2 */
+ NULL, /* process_exit */
+ stop_select
+};
+
+/* III.III The forker driver */
+struct erl_drv_entry forker_driver_entry = {
+ NULL,
+ forker_start,
+ forker_stop,
+ NULL,
+ forker_ready_input,
+ forker_ready_output,
+ "spawn_forker",
+ NULL,
+ NULL,
+ forker_control,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+ ERL_DRV_EXTENDED_MARKER,
+ ERL_DRV_EXTENDED_MAJOR_VERSION,
+ ERL_DRV_EXTENDED_MINOR_VERSION,
+ 0,
+ NULL, NULL,
+ stop_select
+};
+
+/* Untility functions */
+
+static int set_blocking_data(ErtsSysDriverData *dd) {
+
+ dd->blocking = erts_alloc(ERTS_ALC_T_SYS_BLOCKING, sizeof(ErtsSysBlocking));
+
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, sizeof(ErtsSysBlocking));
+
+ dd->blocking->pdl = driver_pdl_create(dd->port_num);
+ dd->blocking->res = 0;
+ dd->blocking->err = 0;
+ dd->blocking->pkey = driver_async_port_key(dd->port_num);
+
+ return 1;
+}
+
+static void init_fd_data(ErtsSysFdData *fd_data, int fd)
+{
+ fd_data->fd = fd;
+ fd_data->buf = NULL;
+ fd_data->cpos = NULL;
+ fd_data->remain = 0;
+ fd_data->sz = 0;
+ fd_data->psz = 0;
+}
+
+static ErtsSysDriverData *
+create_driver_data(ErlDrvPort port_num,
+ int ifd,
+ int ofd,
+ int packet_bytes,
+ int read_write,
+ int exit_status,
+ int pid,
+ int is_blocking)
+{
+ Port *prt;
+ ErtsSysDriverData *driver_data;
+ char *data;
+ int size = sizeof(ErtsSysDriverData);
+
+ if (read_write & DO_READ)
+ size += sizeof(ErtsSysFdData);
+
+ if ((read_write & DO_WRITE) &&
+ ((ifd != ofd || ofd == -1) || !(read_write & DO_READ)))
+ size += sizeof(ErtsSysFdData);
+
+ data = erts_alloc(ERTS_ALC_T_DRV_TAB,size);
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, size);
+
+ driver_data = (ErtsSysDriverData*)data;
+ data += sizeof(*driver_data);
+
+ prt = erts_drvport2port(port_num);
+ if (prt != ERTS_INVALID_ERL_DRV_PORT)
+ prt->os_pid = pid;
+
+ driver_data->packet_bytes = packet_bytes;
+ driver_data->port_num = port_num;
+ driver_data->pid = pid;
+ driver_data->alive = exit_status ? 1 : 0;
+ driver_data->status = 0;
+ driver_data->terminating = 0;
+ driver_data->blocking = NULL;
+
+ if (read_write & DO_READ) {
+ driver_data->ifd = (ErtsSysFdData*)data;
+ data += sizeof(*driver_data->ifd);
+ init_fd_data(driver_data->ifd, ifd);
+ driver_select(port_num, ifd, (ERL_DRV_READ|ERL_DRV_USE), 1);
+ } else {
+ driver_data->ifd = NULL;
+ }
+
+ if (read_write & DO_WRITE) {
+ if (ofd != -1 && ifd == ofd && read_write & DO_READ) {
+ /* This is for when ifd and ofd are the same fd */
+ driver_data->ofd = driver_data->ifd;
+ } else {
+ driver_data->ofd = (ErtsSysFdData*)data;
+ data += sizeof(*driver_data->ofd);
+ init_fd_data(driver_data->ofd, ofd);
+ }
+ if (is_blocking && FDBLOCK)
+ if (!set_blocking_data(driver_data)) {
+ erts_free(ERTS_ALC_T_DRV_TAB, driver_data);
+ return NULL;
+ }
+ } else {
+ driver_data->ofd = NULL;
+ }
+
+ return driver_data;
+}
+
+/* Spawn driver */
+
+static void close_pipes(int ifd[2], int ofd[2])
+{
+ close(ifd[0]);
+ close(ifd[1]);
+ close(ofd[0]);
+ close(ofd[1]);
+}
+
+static char **build_unix_environment(char *block)
+{
+ int i;
+ int j;
+ int len;
+ char *cp;
+ char **cpp;
+ char** old_env;
+
+ ERTS_SMP_LC_ASSERT(erts_smp_lc_rwmtx_is_rlocked(&environ_rwmtx));
+
+ cp = block;
+ len = 0;
+ while (*cp != '\0') {
+ cp += strlen(cp) + 1;
+ len++;
+ }
+ old_env = environ;
+ while (*old_env++ != NULL) {
+ len++;
+ }
+
+ cpp = (char **) erts_alloc_fnf(ERTS_ALC_T_ENVIRONMENT,
+ sizeof(char *) * (len+1));
+ if (cpp == NULL) {
+ return NULL;
+ }
+
+ cp = block;
+ len = 0;
+ while (*cp != '\0') {
+ cpp[len] = cp;
+ cp += strlen(cp) + 1;
+ len++;
+ }
+
+ i = len;
+ for (old_env = environ; *old_env; old_env++) {
+ char* old = *old_env;
+
+ for (j = 0; j < len; j++) {
+ char *s, *t;
+
+ /* check if cpp[j] equals old
+ before the = sign,
+ i.e.
+ "TMPDIR=/tmp/" */
+ s = cpp[j];
+ t = old;
+ while (*s == *t && *s != '=') {
+ s++, t++;
+ }
+ if (*s == '=' && *t == '=') {
+ break;
+ }
+ }
+
+ if (j == len) { /* New version not found */
+ cpp[len++] = old;
+ }
+ }
+
+ for (j = 0; j < i; ) {
+ size_t last = strlen(cpp[j])-1;
+ if (cpp[j][last] == '=' && strchr(cpp[j], '=') == cpp[j]+last) {
+ cpp[j] = cpp[--len];
+ if (len < i) {
+ i--;
+ } else {
+ j++;
+ }
+ }
+ else {
+ j++;
+ }
+ }
+
+ cpp[len] = NULL;
+ return cpp;
+}
+
+static ErlDrvData spawn_start(ErlDrvPort port_num, char* name,
+ SysDriverOpts* opts)
+{
+#define CMD_LINE_PREFIX_STR "exec "
+#define CMD_LINE_PREFIX_STR_SZ (sizeof(CMD_LINE_PREFIX_STR) - 1)
+
+ int len;
+ char **new_environ;
+ ErtsSysDriverData *dd;
+ char *cmd_line;
+ char wd_buff[MAXPATHLEN+1];
+ char *wd;
+ int ifd[2], ofd[2], stderrfd;
+
+ if (pipe(ifd) < 0) return ERL_DRV_ERROR_ERRNO;
+ errno = EMFILE; /* default for next three conditions */
+ if (ifd[0] >= sys_max_files() || pipe(ofd) < 0) {
+ close(ifd[0]);
+ close(ifd[1]);
+ return ERL_DRV_ERROR_ERRNO;
+ }
+ if (ofd[1] >= sys_max_files()) {
+ close_pipes(ifd, ofd);
+ errno = EMFILE;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+
+ SET_NONBLOCKING(ifd[0]);
+ SET_NONBLOCKING(ofd[1]);
+
+ stderrfd = opts->redir_stderr ? ifd[1] : dup(2);
+
+ if (stderrfd >= sys_max_files() || stderrfd < 0) {
+ close_pipes(ifd, ofd);
+ if (stderrfd > -1)
+ close(stderrfd);
+ return ERL_DRV_ERROR_ERRNO;
+ }
+
+ if (opts->spawn_type == ERTS_SPAWN_EXECUTABLE) {
+ /* started with spawn_executable, not with spawn */
+ len = strlen(name);
+ cmd_line = (char *) erts_alloc_fnf(ERTS_ALC_T_TMP, len + 1);
+ if (!cmd_line) {
+ close_pipes(ifd, ofd);
+ errno = ENOMEM;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+ memcpy((void *) cmd_line,(void *) name, len);
+ cmd_line[len] = '\0';
+ len = len + 1;
+ if (access(cmd_line,X_OK) != 0) {
+ int save_errno = errno;
+ erts_free(ERTS_ALC_T_TMP, cmd_line);
+ close_pipes(ifd, ofd);
+ errno = save_errno;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+ } else {
+ /* make the string suitable for giving to "sh" */
+ len = strlen(name);
+ cmd_line = (char *) erts_alloc_fnf(ERTS_ALC_T_TMP,
+ CMD_LINE_PREFIX_STR_SZ + len + 1);
+ if (!cmd_line) {
+ close_pipes(ifd, ofd);
+ errno = ENOMEM;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+ memcpy((void *) cmd_line,
+ (void *) CMD_LINE_PREFIX_STR,
+ CMD_LINE_PREFIX_STR_SZ);
+ memcpy((void *) (cmd_line + CMD_LINE_PREFIX_STR_SZ), (void *) name, len);
+ cmd_line[CMD_LINE_PREFIX_STR_SZ + len] = '\0';
+ len = CMD_LINE_PREFIX_STR_SZ + len + 1;
+ }
+
+ erts_smp_rwmtx_rlock(&environ_rwmtx);
+
+ if (opts->envir == NULL) {
+ new_environ = environ;
+ } else if ((new_environ = build_unix_environment(opts->envir)) == NULL) {
+ erts_smp_rwmtx_runlock(&environ_rwmtx);
+ close_pipes(ifd, ofd);
+ erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
+ errno = ENOMEM;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+
+ if (opts->wd == NULL) {
+ if ((wd = getcwd(wd_buff, MAXPATHLEN+1)) == NULL) {
+ /* on some OSs this call opens a fd in the
+ background which means that this can
+ return EMFILE */
+ int err = errno;
+ close_pipes(ifd, ofd);
+ erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
+ if (new_environ != environ)
+ erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
+ erts_smp_rwmtx_runlock(&environ_rwmtx);
+ errno = err;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+ } else {
+ wd = opts->wd;
+ }
+
+ {
+ struct iovec *io_vector;
+ int iov_len = 5;
+ char nullbuff[] = "\0";
+ int j, i = 0, res;
+ Sint32 buffsz = 0, env_len = 0, argv_len = 0,
+ flags = (opts->use_stdio ? FORKER_FLAG_USE_STDIO : 0)
+ | (opts->exit_status ? FORKER_FLAG_EXIT_STATUS : 0)
+ | (opts->read_write & DO_READ ? FORKER_FLAG_DO_READ : 0)
+ | (opts->read_write & DO_WRITE ? FORKER_FLAG_DO_WRITE : 0);
+
+ /* count number of elements in environment */
+ while(new_environ[env_len] != NULL)
+ env_len++;
+ iov_len += 1 + env_len; /* num envs including size int */
+
+ /* count number of element in argument list */
+ if (opts->spawn_type == ERTS_SPAWN_EXECUTABLE) {
+ if (opts->argv != NULL) {
+ while(opts->argv[argv_len] != NULL)
+ argv_len++;
+ } else {
+ argv_len++;
+ }
+ iov_len += 1 + argv_len; /* num argvs including size int */
+ }
+
+ io_vector = erts_alloc_fnf(ERTS_ALC_T_TMP, sizeof(struct iovec) * iov_len);
+
+ if (!io_vector) {
+ close_pipes(ifd, ofd);
+ erts_smp_rwmtx_runlock(&environ_rwmtx);
+ erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
+ if (new_environ != environ)
+ erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
+ errno = ENOMEM;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+
+ io_vector[i].iov_base = (void*)&buffsz;
+ io_vector[i++].iov_len = sizeof(buffsz);
+
+ io_vector[i].iov_base = (void*)&flags;
+ flags = htonl(flags);
+ io_vector[i++].iov_len = sizeof(flags);
+ buffsz += sizeof(flags);
+
+ io_vector[i].iov_base = cmd_line;
+ io_vector[i++].iov_len = len;
+ buffsz += len;
+
+ io_vector[i].iov_base = wd;
+ io_vector[i].iov_len = strlen(io_vector[i].iov_base) + 1;
+ buffsz += io_vector[i++].iov_len;
+
+ io_vector[i].iov_base = nullbuff;
+ io_vector[i++].iov_len = 1;
+ buffsz += io_vector[i-1].iov_len;
+
+ io_vector[i].iov_base = (void*)&env_len;
+ env_len = htonl(env_len);
+ io_vector[i++].iov_len = sizeof(env_len);
+ buffsz += io_vector[i-1].iov_len;
+
+ for (j = 0; new_environ[j] != NULL; j++) {
+ io_vector[i].iov_base = new_environ[j];
+ io_vector[i++].iov_len = strlen(new_environ[j]) + 1;
+ buffsz += io_vector[i-1].iov_len;
+ }
+
+ /* only append arguments if this was a spawn_executable */
+ if (opts->spawn_type == ERTS_SPAWN_EXECUTABLE) {
+
+ io_vector[i].iov_base = (void*)&argv_len;
+ argv_len = htonl(argv_len);
+ io_vector[i++].iov_len = sizeof(argv_len);
+ buffsz += io_vector[i-1].iov_len;
+
+ if (opts->argv) {
+ /* If there are arguments we copy in the references to
+ them into the iov */
+ for (j = 0; opts->argv[j]; j++) {
+ if (opts->argv[j] == erts_default_arg0)
+ io_vector[i].iov_base = cmd_line;
+ else
+ io_vector[i].iov_base = opts->argv[j];
+ io_vector[i].iov_len = strlen(io_vector[i].iov_base) + 1;
+ buffsz += io_vector[i++].iov_len;
+ }
+ } else {
+ io_vector[i].iov_base = cmd_line;
+ io_vector[i].iov_len = strlen(io_vector[i].iov_base) + 1;
+ buffsz += io_vector[i++].iov_len;
+ }
+ }
+
+ /* we send the request to do the fork */
+ if ((res = writev(ofd[1], io_vector, iov_len > MAXIOV ? MAXIOV : iov_len)) < 0) {
+ if (errno == ERRNO_BLOCK) {
+ res = 0;
+ } else {
+ int err = errno;
+ close_pipes(ifd, ofd);
+ erts_free(ERTS_ALC_T_TMP, io_vector);
+ if (new_environ != environ)
+ erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
+ erts_smp_rwmtx_runlock(&environ_rwmtx);
+ erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
+ errno = err;
+ return ERL_DRV_ERROR_ERRNO;
+ }
+ }
+
+ if (res < buffsz) {
+ /* we only wrote part of the command payload. Enqueue the rest. */
+ for (i = 0; i < iov_len; i++) {
+ driver_enq(port_num, io_vector[i].iov_base, io_vector[i].iov_len);
+ }
+ driver_deq(port_num, res);
+ driver_select(port_num, ofd[1], ERL_DRV_WRITE|ERL_DRV_USE, 1);
+ }
+
+ erts_free(ERTS_ALC_T_TMP, io_vector);
+ }
+
+ erts_free(ERTS_ALC_T_TMP, (void *) cmd_line);
+
+ if (new_environ != environ)
+ erts_free(ERTS_ALC_T_ENVIRONMENT, (void *) new_environ);
+
+ erts_smp_rwmtx_runlock(&environ_rwmtx);
+
+ dd = create_driver_data(port_num, ifd[0], ofd[1], opts->packet_bytes,
+ DO_WRITE | DO_READ, opts->exit_status,
+ 0, 0);
+
+ {
+ /* send ofd[0] + ifd[1] + stderrfd to forker port */
+ ErtsSysForkerProto *proto =
+ erts_alloc(ERTS_ALC_T_DRV_CTRL_DATA,
+ sizeof(ErtsSysForkerProto));
+ memset(proto, 0, sizeof(ErtsSysForkerProto));
+ proto->action = ErtsSysForkerProtoAction_Start;
+ proto->u.start.fds[0] = ofd[0];
+ proto->u.start.fds[1] = ifd[1];
+ proto->u.start.fds[2] = stderrfd;
+ proto->u.start.port_id = opts->exit_status ? erts_drvport2id(port_num) : THE_NON_VALUE;
+ if (erl_drv_port_control(forker_port, 'S', (char*)proto, sizeof(*proto))) {
+ /* The forker port has been killed, we close both fd's which will
+ make open_port throw an epipe error */
+ close(ofd[0]);
+ close(ifd[1]);
+ }
+ }
+
+ /* we set these fds to negative to mark if
+ they should be closed after the handshake */
+ if (!(opts->read_write & DO_READ))
+ dd->ifd->fd *= -1;
+
+ if (!(opts->read_write & DO_WRITE))
+ dd->ofd->fd *= -1;
+
+ return (ErlDrvData)dd;
+#undef CMD_LINE_PREFIX_STR
+#undef CMD_LINE_PREFIX_STR_SZ
+}
+
+static ErlDrvSSizeT spawn_control(ErlDrvData e, unsigned int cmd, char *buf,
+ ErlDrvSizeT len, char **rbuf, ErlDrvSizeT rlen)
+{
+ ErtsSysDriverData *dd = (ErtsSysDriverData*)e;
+ ErtsSysForkerProto *proto = (ErtsSysForkerProto *)buf;
+
+ ASSERT(len == sizeof(*proto));
+ ASSERT(proto->action == ErtsSysForkerProtoAction_SigChld);
+
+ dd->status = proto->u.sigchld.error_number;
+ dd->alive = -1;
+
+ if (dd->ifd)
+ driver_select(dd->port_num, abs(dd->ifd->fd), ERL_DRV_READ | ERL_DRV_USE, 1);
+
+ if (dd->ofd)
+ driver_select(dd->port_num, abs(dd->ofd->fd), ERL_DRV_WRITE | ERL_DRV_USE, 1);
+
+ return 0;
+}
+
+#define FD_DEF_HEIGHT 24
+#define FD_DEF_WIDTH 80
+/* Control op */
+#define FD_CTRL_OP_GET_WINSIZE 100
+
+static int fd_get_window_size(int fd, Uint32 *width, Uint32 *height)
+{
+#ifdef TIOCGWINSZ
+ struct winsize ws;
+ if (ioctl(fd,TIOCGWINSZ,&ws) == 0) {
+ *width = (Uint32) ws.ws_col;
+ *height = (Uint32) ws.ws_row;
+ return 0;
+ }
+#endif
+ return -1;
+}
+
+static ErlDrvSSizeT fd_control(ErlDrvData drv_data,
+ unsigned int command,
+ char *buf, ErlDrvSizeT len,
+ char **rbuf, ErlDrvSizeT rlen)
+{
+ int fd = (int)(long)drv_data;
+ char resbuff[2*sizeof(Uint32)];
+ switch (command) {
+ case FD_CTRL_OP_GET_WINSIZE:
+ {
+ Uint32 w,h;
+ if (fd_get_window_size(fd,&w,&h))
+ return 0;
+ memcpy(resbuff,&w,sizeof(Uint32));
+ memcpy(resbuff+sizeof(Uint32),&h,sizeof(Uint32));
+ }
+ break;
+ default:
+ return 0;
+ }
+ if (rlen < 2*sizeof(Uint32)) {
+ *rbuf = driver_alloc(2*sizeof(Uint32));
+ }
+ memcpy(*rbuf,resbuff,2*sizeof(Uint32));
+ return 2*sizeof(Uint32);
+}
+
+static ErlDrvData fd_start(ErlDrvPort port_num, char* name,
+ SysDriverOpts* opts)
+{
+ int non_blocking = 0;
+
+ if (((opts->read_write & DO_READ) && opts->ifd >= sys_max_files()) ||
+ ((opts->read_write & DO_WRITE) && opts->ofd >= sys_max_files()))
+ return ERL_DRV_ERROR_GENERAL;
+
+ /*
+ * Historical:
+ *
+ * "Note about nonblocking I/O.
+ *
+ * At least on Solaris, setting the write end of a TTY to nonblocking,
+ * will set the input end to nonblocking as well (and vice-versa).
+ * If erl is run in a pipeline like this: cat | erl
+ * the input end of the TTY will be the standard input of cat.
+ * And cat is not prepared to handle nonblocking I/O."
+ *
+ * Actually, the reason for this is not that the tty itself gets set
+ * in non-blocking mode, but that the "input end" (cat's stdin) and
+ * the "output end" (erlang's stdout) are typically the "same" file
+ * descriptor, dup()'ed from a single fd by one of this process'
+ * ancestors.
+ *
+ * The workaround for this problem used to be a rather bad kludge,
+ * interposing an extra process ("internal cat") between erlang's
+ * stdout and the original stdout, allowing erlang to set its stdout
+ * in non-blocking mode without affecting the stdin of the preceding
+ * process in the pipeline - and being a kludge, it caused all kinds
+ * of weird problems.
+ *
+ * So, this is the current logic:
+ *
+ * The only reason to set non-blocking mode on the output fd at all is
+ * if it's something that can cause a write() to block, of course,
+ * i.e. primarily if it points to a tty, socket, pipe, or fifo.
+ *
+ * If we don't set non-blocking mode when we "should" have, and output
+ * becomes blocked, the entire runtime system will be suspended - this
+ * is normally bad of course, and can happen fairly "easily" - e.g. user
+ * hits ^S on tty - but doesn't necessarily happen.
+ *
+ * If we do set non-blocking mode when we "shouldn't" have, the runtime
+ * system will end up seeing EOF on the input fd (due to the preceding
+ * process dying), which typically will cause the entire runtime system
+ * to terminate immediately (due to whatever erlang process is seeing
+ * the EOF taking it as a signal to halt the system). This is *very* bad.
+ *
+ * I.e. we should take a conservative approach, and only set non-
+ * blocking mode when we a) need to, and b) are reasonably certain
+ * that it won't be a problem. And as in the example above, the problem
+ * occurs when input fd and output fd point to different "things".
+ *
+ * However, determining that they are not just the same "type" of
+ * "thing", but actually the same instance of that type of thing, is
+ * unreasonably complex in many/most cases.
+ *
+ * Also, with pipes, sockets, and fifos it's far from obvious that the
+ * user *wants* non-blocking output: If you're running erlang inside
+ * some complex pipeline, you're probably not running a real-time system
+ * that must never stop, but rather *want* it to suspend if the output
+ * channel is "full".
+ *
+ * So, the bottom line: We will only set the output fd non-blocking if
+ * it points to a tty, and either a) the input fd also points to a tty,
+ * or b) we can make sure that setting the output fd non-blocking
+ * doesn't interfere with someone else's input, via a somewhat milder
+ * kludge than the above.
+ *
+ * Also keep in mind that while this code is almost exclusively run as
+ * a result of an erlang open_port({fd,0,1}, ...), that isn't the only
+ * case - it can be called with any old pre-existing file descriptors,
+ * the relations between which (if they're even two) we can only guess
+ * at - still, we try our best...
+ *
+ * Added note OTP 18: Some systems seem to use stdout/stderr to log data
+ * using unix pipes, so we cannot allow the system to block on a write.
+ * Therefore we use an async thread to write the data to fd's that could
+ * not be set to non-blocking. When no async threads are available we
+ * fall back on the old behaviour.
+ *
+ * Also the guarantee about what is delivered to the OS has changed.
+ * Pre 18 the fd driver did no flushing of data before terminating.
+ * Now it does. This is because we want to be able to guarantee that things
+ * such as escripts and friends really have outputted all data before
+ * terminating. This could potentially block the termination of the system
+ * for a very long time, but if the user wants to terminate fast she should
+ * use erlang:halt with flush=false.
+ */
+
+ /* Try to figure out if we can use non-blocking writes */
+ if (opts->read_write & DO_WRITE) {
+
+ /* If we don't have a read end, all bets are off - no non-blocking. */
+ if (opts->read_write & DO_READ) {
+
+ if (isatty(opts->ofd)) { /* output fd is a tty:-) */
+
+ if (isatty(opts->ifd)) { /* input fd is also a tty */
+
+ /* To really do this "right", we should also check that
+ input and output fd point to the *same* tty - but
+ this seems like overkill; ttyname() isn't for free,
+ and this is a very common case - and it's hard to
+ imagine a scenario where setting non-blocking mode
+ here would cause problems - go ahead and do it. */
+
+ non_blocking = 1;
+ SET_NONBLOCKING(opts->ofd);
+
+ } else { /* output fd is a tty, input fd isn't */
+
+ /* This is a "problem case", but also common (see the
+ example above) - i.e. it makes sense to try a bit
+ harder before giving up on non-blocking mode: Try to
+ re-open the tty that the output fd points to, and if
+ successful replace the original one with the "new" fd
+ obtained this way, and set *that* one in non-blocking
+ mode. (Yes, this is a kludge.)
+
+ However, re-opening the tty may fail in a couple of
+ (unusual) cases:
+
+ 1) The name of the tty (or an equivalent one, i.e.
+ same major/minor number) can't be found, because
+ it actually lives somewhere other than /dev (or
+ wherever ttyname() looks for it), and isn't
+ equivalent to any of those that do live in the
+ "standard" place - this should be *very* unusual.
+
+ 2) Permissions on the tty don't allow us to open it -
+ it's perfectly possible to have an fd open to an
+ object whose permissions wouldn't allow us to open
+ it. This is not as unusual as it sounds, one case
+ is if the user has su'ed to someone else (not
+ root) - we have a read/write fd open to the tty
+ (because it has been inherited all the way down
+ here), but we have neither read nor write
+ permission for the tty.
+
+ In these cases, we finally give up, and don't set the
+ output fd in non-blocking mode. */
+
+ char *tty;
+ int nfd;
+
+ if ((tty = ttyname(opts->ofd)) != NULL &&
+ (nfd = open(tty, O_WRONLY)) != -1) {
+ dup2(nfd, opts->ofd);
+ close(nfd);
+ non_blocking = 1;
+ SET_NONBLOCKING(opts->ofd);
+ }
+ }
+ }
+ }
+ }
+ return (ErlDrvData)create_driver_data(port_num, opts->ifd, opts->ofd,
+ opts->packet_bytes,
+ opts->read_write, 0, -1,
+ !non_blocking);
+}
+
+static void clear_fd_data(ErtsSysFdData *fdd)
+{
+ if (fdd->sz > 0) {
+ erts_free(ERTS_ALC_T_FD_ENTRY_BUF, (void *) fdd->buf);
+ ASSERT(erts_smp_atomic_read_nob(&sys_misc_mem_sz) >= fdd->sz);
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, -1*fdd->sz);
+ }
+ fdd->buf = NULL;
+ fdd->sz = 0;
+ fdd->remain = 0;
+ fdd->cpos = NULL;
+ fdd->psz = 0;
+}
+
+static void nbio_stop_fd(ErlDrvPort prt, ErtsSysFdData *fdd)
+{
+ driver_select(prt, abs(fdd->fd), DO_READ|DO_WRITE, 0);
+ clear_fd_data(fdd);
+ SET_BLOCKING(abs(fdd->fd));
+
+}
+
+static void fd_stop(ErlDrvData ev) /* Does not close the fds */
+{
+ ErtsSysDriverData* dd = (ErtsSysDriverData*)ev;
+ ErlDrvPort prt = dd->port_num;
+ int sz = sizeof(ErtsSysDriverData);
+
+#if FDBLOCK
+ if (dd->blocking) {
+ erts_free(ERTS_ALC_T_SYS_BLOCKING, dd->blocking);
+ dd->blocking = NULL;
+ sz += sizeof(ErtsSysBlocking);
+ }
+#endif
+
+ if (dd->ifd) {
+ sz += sizeof(ErtsSysFdData);
+ nbio_stop_fd(prt, dd->ifd);
+ }
+ if (dd->ofd && dd->ofd != dd->ifd) {
+ sz += sizeof(ErtsSysFdData);
+ nbio_stop_fd(prt, dd->ofd);
+ }
+
+ erts_free(ERTS_ALC_T_DRV_TAB, dd);
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, -sz);
+}
+
+static void fd_flush(ErlDrvData ev)
+{
+ ErtsSysDriverData* dd = (ErtsSysDriverData*)ev;
+ if (!dd->terminating)
+ dd->terminating = 1;
+}
+
+static ErlDrvData vanilla_start(ErlDrvPort port_num, char* name,
+ SysDriverOpts* opts)
+{
+ int flags, fd;
+ ErlDrvData res;
+
+ flags = (opts->read_write == DO_READ ? O_RDONLY :
+ opts->read_write == DO_WRITE ? O_WRONLY|O_CREAT|O_TRUNC :
+ O_RDWR|O_CREAT);
+ if ((fd = open(name, flags, 0666)) < 0)
+ return ERL_DRV_ERROR_GENERAL;
+ if (fd >= sys_max_files()) {
+ close(fd);
+ return ERL_DRV_ERROR_GENERAL;
+ }
+ SET_NONBLOCKING(fd);
+
+ res = (ErlDrvData)(long)create_driver_data(port_num, fd, fd,
+ opts->packet_bytes,
+ opts->read_write, 0, -1, 0);
+ return res;
+}
+
+/* Note that driver_data[fd].ifd == fd if the port was opened for reading, */
+/* otherwise (i.e. write only) driver_data[fd].ofd = fd. */
+
+static void stop(ErlDrvData ev)
+{
+ ErtsSysDriverData* dd = (ErtsSysDriverData*)ev;
+ ErlDrvPort prt = dd->port_num;
+
+ if (dd->ifd) {
+ nbio_stop_fd(prt, dd->ifd);
+ driver_select(prt, abs(dd->ifd->fd), ERL_DRV_USE, 0); /* close(ifd); */
+ }
+
+ if (dd->ofd && dd->ofd != dd->ifd) {
+ nbio_stop_fd(prt, dd->ofd);
+ driver_select(prt, abs(dd->ofd->fd), ERL_DRV_USE, 0); /* close(ofd); */
+ }
+
+ erts_free(ERTS_ALC_T_DRV_TAB, dd);
+}
+
+/* used by fd_driver */
+static void outputv(ErlDrvData e, ErlIOVec* ev)
+{
+ ErtsSysDriverData *dd = (ErtsSysDriverData*)e;
+ ErlDrvPort ix = dd->port_num;
+ int pb = dd->packet_bytes;
+ int ofd = dd->ofd ? dd->ofd->fd : -1;
+ ssize_t n;
+ ErlDrvSizeT sz;
+ char lb[4];
+ char* lbp;
+ ErlDrvSizeT len = ev->size;
+
+ /* (len > ((unsigned long)-1 >> (4-pb)*8)) */
+ /* if (pb >= 0 && (len & (((ErlDrvSizeT)1 << (pb*8))) - 1) != len) {*/
+ if (((pb == 2) && (len > 0xffff)) || (pb == 1 && len > 0xff)) {
+ driver_failure_posix(ix, EINVAL);
+ return; /* -1; */
+ }
+ /* Handles 0 <= pb <= 4 only */
+ put_int32((Uint32) len, lb);
+ lbp = lb + (4-pb);
+
+ ev->iov[0].iov_base = lbp;
+ ev->iov[0].iov_len = pb;
+ ev->size += pb;
+
+ if (dd->blocking && FDBLOCK)
+ driver_pdl_lock(dd->blocking->pdl);
+
+ if ((sz = driver_sizeq(ix)) > 0) {
+ driver_enqv(ix, ev, 0);
+
+ if (dd->blocking && FDBLOCK)
+ driver_pdl_unlock(dd->blocking->pdl);
+
+ if (sz + ev->size >= (1 << 13))
+ set_busy_port(ix, 1);
+ }
+ else if (!dd->blocking || !FDBLOCK) {
+ /* We try to write directly if the fd in non-blocking */
+ int vsize = ev->vsize > MAX_VSIZE ? MAX_VSIZE : ev->vsize;
+
+ n = writev(ofd, (const void *) (ev->iov), vsize);
+ if (n == ev->size)
+ return; /* 0;*/
+ if (n < 0) {
+ if ((errno != EINTR) && (errno != ERRNO_BLOCK)) {
+ driver_failure_posix(ix, errno);
+ return; /* -1;*/
+ }
+ n = 0;
+ }
+ driver_enqv(ix, ev, n); /* n is the skip value */
+ driver_select(ix, ofd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
+ }
+#if FDBLOCK
+ else {
+ if (ev->size != 0) {
+ driver_enqv(ix, ev, 0);
+ driver_pdl_unlock(dd->blocking->pdl);
+ driver_async(ix, &dd->blocking->pkey,
+ fd_async, dd, NULL);
+ } else {
+ driver_pdl_unlock(dd->blocking->pdl);
+ }
+ }
+#endif
+ /* return 0;*/
+}
+
+/* Used by spawn_driver and vanilla driver */
+static void output(ErlDrvData e, char* buf, ErlDrvSizeT len)
+{
+ ErtsSysDriverData *dd = (ErtsSysDriverData*)e;
+ ErlDrvPort ix = dd->port_num;
+ int pb = dd->packet_bytes;
+ int ofd = dd->ofd ? dd->ofd->fd : -1;
+ ssize_t n;
+ ErlDrvSizeT sz;
+ char lb[4];
+ char* lbp;
+ struct iovec iv[2];
+
+ /* (len > ((unsigned long)-1 >> (4-pb)*8)) */
+ if (((pb == 2) && (len > 0xffff))
+ || (pb == 1 && len > 0xff)
+ || dd->pid == 0 /* Attempt at output before port is ready */) {
+ driver_failure_posix(ix, EINVAL);
+ return; /* -1; */
+ }
+ put_int32(len, lb);
+ lbp = lb + (4-pb);
+
+ if ((sz = driver_sizeq(ix)) > 0) {
+ driver_enq(ix, lbp, pb);
+ driver_enq(ix, buf, len);
+ if (sz + len + pb >= (1 << 13))
+ set_busy_port(ix, 1);
+ }
+ else {
+ iv[0].iov_base = lbp;
+ iv[0].iov_len = pb; /* should work for pb=0 */
+ iv[1].iov_base = buf;
+ iv[1].iov_len = len;
+ n = writev(ofd, iv, 2);
+ if (n == pb+len)
+ return; /* 0; */
+ if (n < 0) {
+ if ((errno != EINTR) && (errno != ERRNO_BLOCK)) {
+ driver_failure_posix(ix, errno);
+ return; /* -1; */
+ }
+ n = 0;
+ }
+ if (n < pb) {
+ driver_enq(ix, lbp+n, pb-n);
+ driver_enq(ix, buf, len);
+ }
+ else {
+ n -= pb;
+ driver_enq(ix, buf+n, len-n);
+ }
+ driver_select(ix, ofd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
+ }
+ return; /* 0; */
+}
+
+static int port_inp_failure(ErtsSysDriverData *dd, int res)
+ /* Result: 0 (eof) or -1 (error) */
+{
+ int err = errno;
+
+ ASSERT(res <= 0);
+ if (dd->ifd) {
+ driver_select(dd->port_num, dd->ifd->fd, ERL_DRV_READ|ERL_DRV_WRITE, 0);
+ clear_fd_data(dd->ifd);
+ }
+
+ if (dd->blocking && FDBLOCK) {
+ driver_pdl_lock(dd->blocking->pdl);
+ if (driver_sizeq(dd->port_num) > 0) {
+ driver_pdl_unlock(dd->blocking->pdl);
+ /* We have stuff in the output queue, so we just
+ set the state to terminating and wait for fd_async_ready
+ to terminate the port */
+ if (res == 0)
+ dd->terminating = 2;
+ else
+ dd->terminating = -err;
+ return 0;
+ }
+ driver_pdl_unlock(dd->blocking->pdl);
+ }
+
+ if (res == 0) {
+ if (dd->alive == 1) {
+ /*
+ * We have eof and want to report exit status, but the process
+ * hasn't exited yet. When it does ready_input will
+ * driver_select() this fd which will make sure that we get
+ * back here with dd->alive == -1 and dd->status set.
+ */
+ return 0;
+ }
+ else if (dd->alive == -1) {
+ int status = dd->status;
+
+ /* We need not be prepared for stopped/continued processes. */
+ if (WIFSIGNALED(status))
+ status = 128 + WTERMSIG(status);
+ else
+ status = WEXITSTATUS(status);
+ driver_report_exit(dd->port_num, status);
+ }
+ driver_failure_eof(dd->port_num);
+ } else if (dd->ifd) {
+ erl_drv_init_ack(dd->port_num, ERL_DRV_ERROR_ERRNO);
+ } else {
+ driver_failure_posix(dd->port_num, err);
+ }
+ return 0;
+}
+
+/* fd is the drv_data that is returned from the */
+/* initial start routine */
+/* ready_fd is the descriptor that is ready to read */
+
+static void ready_input(ErlDrvData e, ErlDrvEvent ready_fd)
+{
+ ErtsSysDriverData *dd = (ErtsSysDriverData*)e;
+ ErlDrvPort port_num;
+ int packet_bytes;
+ int res;
+ Uint h;
+
+ port_num = dd->port_num;
+ packet_bytes = dd->packet_bytes;
+
+ ASSERT(abs(dd->ifd->fd) == ready_fd);
+
+ if (dd->pid == 0) {
+ /* the pid is sent from erl_child_setup. spawn driver only. */
+ ErtsSysForkerProto proto;
+ int res;
+
+ if((res = read(ready_fd, &proto, sizeof(proto))) <= 0) {
+ /* hmm, child setup seems to have closed the pipe too early...
+ we close the port as there is not much else we can do */
+ if (res < 0 && errno == ERRNO_BLOCK)
+ return;
+ driver_select(port_num, ready_fd, ERL_DRV_READ, 0);
+ if (res == 0)
+ errno = EPIPE;
+ port_inp_failure(dd, -1);
+ return;
+ }
+
+ ASSERT(proto.action == ErtsSysForkerProtoAction_Go);
+ dd->pid = proto.u.go.os_pid;
+
+ if (dd->pid == -1) {
+ /* Setup failed! The only reason why this should happen is if
+ the fork fails. */
+ errno = proto.u.go.error_number;
+ port_inp_failure(dd, -1);
+ return;
+ }
+
+ proto.action = ErtsSysForkerProtoAction_Ack;
+
+ if (driver_sizeq(port_num) > 0) {
+ driver_enq(port_num, (char*)&proto, sizeof(proto));
+ } else {
+ if (write(abs(dd->ofd->fd), &proto, sizeof(proto)) < 0)
+ if (errno == ERRNO_BLOCK || errno == EINTR)
+ driver_enq(port_num, (char*)&proto, sizeof(proto));
+ /* do nothing on failure here. If the ofd is broken, then
+ the ifd will probably also be broken and trigger
+ a port_inp_failure */
+ }
+
+ if (dd->ifd->fd < 0) {
+ driver_select(port_num, abs(dd->ifd->fd), ERL_DRV_READ|ERL_DRV_USE, 0);
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, -sizeof(ErtsSysFdData));
+ dd->ifd = NULL;
+ }
+
+ if (dd->ofd->fd < 0 || driver_sizeq(port_num) > 0)
+ /* we select in order to close fd or write to queue,
+ child setup will close this fd if fd < 0 */
+ driver_select(port_num, abs(dd->ofd->fd), ERL_DRV_WRITE|ERL_DRV_USE, 1);
+
+ erl_drv_set_os_pid(port_num, dd->pid);
+ erl_drv_init_ack(port_num, e);
+ return;
+ }
+
+ if (packet_bytes == 0) {
+ byte *read_buf = (byte *) erts_alloc(ERTS_ALC_T_SYS_READ_BUF,
+ ERTS_SYS_READ_BUF_SZ);
+ res = read(ready_fd, read_buf, ERTS_SYS_READ_BUF_SZ);
+ if (res < 0) {
+ if ((errno != EINTR) && (errno != ERRNO_BLOCK))
+ port_inp_failure(dd, res);
+ }
+ else if (res == 0)
+ port_inp_failure(dd, res);
+ else
+ driver_output(port_num, (char*) read_buf, res);
+ erts_free(ERTS_ALC_T_SYS_READ_BUF, (void *) read_buf);
+ }
+ else if (dd->ifd->remain > 0) { /* We try to read the remainder */
+ /* space is allocated in buf */
+ res = read(ready_fd, dd->ifd->cpos,
+ dd->ifd->remain);
+ if (res < 0) {
+ if ((errno != EINTR) && (errno != ERRNO_BLOCK))
+ port_inp_failure(dd, res);
+ }
+ else if (res == 0) {
+ port_inp_failure(dd, res);
+ }
+ else if (res == dd->ifd->remain) { /* we're done */
+ driver_output(port_num, dd->ifd->buf,
+ dd->ifd->sz);
+ clear_fd_data(dd->ifd);
+ }
+ else { /* if (res < dd->ifd->remain) */
+ dd->ifd->cpos += res;
+ dd->ifd->remain -= res;
+ }
+ }
+ else if (dd->ifd->remain == 0) { /* clean fd */
+ byte *read_buf = (byte *) erts_alloc(ERTS_ALC_T_SYS_READ_BUF,
+ ERTS_SYS_READ_BUF_SZ);
+ /* We make one read attempt and see what happens */
+ res = read(ready_fd, read_buf, ERTS_SYS_READ_BUF_SZ);
+ if (res < 0) {
+ if ((errno != EINTR) && (errno != ERRNO_BLOCK))
+ port_inp_failure(dd, res);
+ }
+ else if (res == 0) { /* eof */
+ port_inp_failure(dd, res);
+ }
+ else if (res < packet_bytes - dd->ifd->psz) {
+ memcpy(dd->ifd->pbuf+dd->ifd->psz,
+ read_buf, res);
+ dd->ifd->psz += res;
+ }
+ else { /* if (res >= packet_bytes) */
+ unsigned char* cpos = read_buf;
+ int bytes_left = res;
+
+ while (1) {
+ int psz = dd->ifd->psz;
+ char* pbp = dd->ifd->pbuf + psz;
+
+ while(bytes_left && (psz < packet_bytes)) {
+ *pbp++ = *cpos++;
+ bytes_left--;
+ psz++;
+ }
+
+ if (psz < packet_bytes) {
+ dd->ifd->psz = psz;
+ break;
+ }
+ dd->ifd->psz = 0;
+
+ switch (packet_bytes) {
+ case 1: h = get_int8(dd->ifd->pbuf); break;
+ case 2: h = get_int16(dd->ifd->pbuf); break;
+ case 4: h = get_int32(dd->ifd->pbuf); break;
+ default: ASSERT(0); return; /* -1; */
+ }
+
+ if (h <= (bytes_left)) {
+ driver_output(port_num, (char*) cpos, h);
+ cpos += h;
+ bytes_left -= h;
+ continue;
+ }
+ else { /* The last message we got was split */
+ char *buf = erts_alloc_fnf(ERTS_ALC_T_FD_ENTRY_BUF, h);
+ if (!buf) {
+ errno = ENOMEM;
+ port_inp_failure(dd, -1);
+ }
+ else {
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, h);
+ sys_memcpy(buf, cpos, bytes_left);
+ dd->ifd->buf = buf;
+ dd->ifd->sz = h;
+ dd->ifd->remain = h - bytes_left;
+ dd->ifd->cpos = buf + bytes_left;
+ }
+ break;
+ }
+ }
+ }
+ erts_free(ERTS_ALC_T_SYS_READ_BUF, (void *) read_buf);
+ }
+}
+
+
+/* fd is the drv_data that is returned from the */
+/* initial start routine */
+/* ready_fd is the descriptor that is ready to read */
+
+static void ready_output(ErlDrvData e, ErlDrvEvent ready_fd)
+{
+ ErtsSysDriverData *dd = (ErtsSysDriverData*)e;
+ ErlDrvPort ix = dd->port_num;
+ int n;
+ struct iovec* iv;
+ int vsize;
+
+ if ((iv = (struct iovec*) driver_peekq(ix, &vsize)) == NULL) {
+ driver_select(ix, ready_fd, ERL_DRV_WRITE, 0);
+ if (dd->pid > 0 && dd->ofd->fd < 0) {
+ /* The port was opened with 'in' option, which means we
+ should close the output fd as soon as the command has
+ been sent. */
+ driver_select(ix, ready_fd, ERL_DRV_WRITE|ERL_DRV_USE, 0);
+ erts_smp_atomic_add_nob(&sys_misc_mem_sz, -sizeof(ErtsSysFdData));
+ dd->ofd = NULL;
+ }
+ if (dd->terminating)
+ driver_failure_atom(dd->port_num,"normal");
+ return; /* 0; */
+ }
+ vsize = vsize > MAX_VSIZE ? MAX_VSIZE : vsize;
+ if ((n = writev(ready_fd, iv, vsize)) > 0) {
+ if (driver_deq(ix, n) == 0)
+ set_busy_port(ix, 0);
+ }
+ else if (n < 0) {
+ if (errno == ERRNO_BLOCK || errno == EINTR)
+ return; /* 0; */
+ else {
+ int res = errno;
+ driver_select(ix, ready_fd, ERL_DRV_WRITE, 0);
+ driver_failure_posix(ix, res);
+ return; /* -1; */
+ }
+ }
+ return; /* 0; */
+}
+
+static void stop_select(ErlDrvEvent fd, void* _)
+{
+ close((int)fd);
+}
+
+#if FDBLOCK
+
+static void
+fd_async(void *async_data)
+{
+ int res;
+ ErtsSysDriverData *dd = (ErtsSysDriverData *)async_data;
+ SysIOVec *iov0;
+ SysIOVec *iov;
+ int iovlen;
+ int err = 0;
+ /* much of this code is stolen from efile_drv:invoke_writev */
+ driver_pdl_lock(dd->blocking->pdl);
+ iov0 = driver_peekq(dd->port_num, &iovlen);
+ iovlen = iovlen < MAXIOV ? iovlen : MAXIOV;
+ iov = erts_alloc_fnf(ERTS_ALC_T_SYS_WRITE_BUF,
+ sizeof(SysIOVec)*iovlen);
+ if (!iov) {
+ res = -1;
+ err = ENOMEM;
+ driver_pdl_unlock(dd->blocking->pdl);
+ } else {
+ memcpy(iov,iov0,iovlen*sizeof(SysIOVec));
+ driver_pdl_unlock(dd->blocking->pdl);
+
+ do {
+ res = writev(dd->ofd->fd, iov, iovlen);
+ } while (res < 0 && errno == EINTR);
+ if (res < 0)
+ err = errno;
+ err = errno;
+
+ erts_free(ERTS_ALC_T_SYS_WRITE_BUF, iov);
+ }
+ dd->blocking->res = res;
+ dd->blocking->err = err;
+}
+
+void fd_ready_async(ErlDrvData drv_data,
+ ErlDrvThreadData thread_data) {
+ ErtsSysDriverData *dd = (ErtsSysDriverData *)thread_data;
+ ErlDrvPort port_num = dd->port_num;
+
+ ASSERT(dd->blocking);
+
+ if (dd->blocking->res > 0) {
+ driver_pdl_lock(dd->blocking->pdl);
+ if (driver_deq(port_num, dd->blocking->res) == 0) {
+ driver_pdl_unlock(dd->blocking->pdl);
+ set_busy_port(port_num, 0);
+ if (dd->terminating) {
+ /* The port is has been ordered to terminate
+ from either fd_flush or port_inp_failure */
+ if (dd->terminating == 1)
+ driver_failure_atom(port_num, "normal");
+ else if (dd->terminating == 2)
+ driver_failure_eof(port_num);
+ else if (dd->terminating < 0)
+ driver_failure_posix(port_num, -dd->terminating);
+ return; /* -1; */
+ }
+ } else {
+ driver_pdl_unlock(dd->blocking->pdl);
+ /* still data left to write in queue */
+ driver_async(port_num, &dd->blocking->pkey, fd_async, dd, NULL);
+ return /* 0; */;
+ }
+ } else if (dd->blocking->res < 0) {
+ if (dd->blocking->err == ERRNO_BLOCK) {
+ set_busy_port(port_num, 1);
+ /* still data left to write in queue */
+ driver_async(port_num, &dd->blocking->pkey, fd_async, dd, NULL);
+ } else
+ driver_failure_posix(port_num, dd->blocking->err);
+ return; /* -1; */
+ }
+ return; /* 0; */
+}
+
+#endif
+
+/* Forker driver */
+
+static int forker_fd;
+
+static ErlDrvData forker_start(ErlDrvPort port_num, char* name,
+ SysDriverOpts* opts)
+{
+
+ int i;
+ int fds[2];
+ int res, unbind;
+ char bindir[MAXPATHLEN];
+ size_t bindirsz = sizeof(bindir);
+ Uint csp_path_sz;
+ char *child_setup_prog;
+
+ forker_port = erts_drvport2id(port_num);
+
+ res = erts_sys_getenv_raw("BINDIR", bindir, &bindirsz);
+ if (res != 0) {
+ if (res < 0)
+ erl_exit(-1,
+ "Environment variable BINDIR is not set\n");
+ if (res > 0)
+ erl_exit(-1,
+ "Value of environment variable BINDIR is too large\n");
+ }
+ if (bindir[0] != DIR_SEPARATOR_CHAR)
+ erl_exit(-1,
+ "Environment variable BINDIR does not contain an"
+ " absolute path\n");
+ csp_path_sz = (strlen(bindir)
+ + 1 /* DIR_SEPARATOR_CHAR */
+ + sizeof(CHILD_SETUP_PROG_NAME)
+ + 1);
+ child_setup_prog = erts_alloc(ERTS_ALC_T_CS_PROG_PATH, csp_path_sz);
+ erts_snprintf(child_setup_prog, csp_path_sz,
+ "%s%c%s",
+ bindir,
+ DIR_SEPARATOR_CHAR,
+ CHILD_SETUP_PROG_NAME);
+ if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds) < 0) {
+ erl_exit(ERTS_ABORT_EXIT,
+ "Could not open unix domain socket in spawn_init: %d\n",
+ errno);
+ }
+
+ forker_fd = fds[0];
+
+ unbind = erts_sched_bind_atfork_prepare();
+
+ i = fork();
+
+ if (i == 0) {
+ /* The child */
+ char *cs_argv[FORKER_ARGV_NO_OF_ARGS] =
+ {CHILD_SETUP_PROG_NAME, NULL, NULL};
+ char buff[128];
+
+ erts_sched_bind_atfork_child(unbind);
+
+ snprintf(buff, 128, "%d", sys_max_files());
+ cs_argv[FORKER_ARGV_MAX_FILES] = buff;
+
+ /* We preallocate fd 3 for the uds fd */
+ if (fds[1] != 3) {
+ dup2(fds[1], 3);
+ }
+
+#if defined(USE_SETPGRP_NOARGS) /* SysV */
+ (void) setpgrp();
+#elif defined(USE_SETPGRP) /* BSD */
+ (void) setpgrp(0, getpid());
+#else /* POSIX */
+ (void) setsid();
+#endif
+
+ execv(child_setup_prog, cs_argv);
+ _exit(1);
+ }
+
+ erts_sched_bind_atfork_parent(unbind);
+
+ erts_free(ERTS_ALC_T_CS_PROG_PATH, child_setup_prog);
+
+ close(fds[1]);
+
+ SET_NONBLOCKING(forker_fd);
+
+ driver_select(port_num, forker_fd, ERL_DRV_READ|ERL_DRV_USE, 1);
+
+ return (ErlDrvData)port_num;
+}
+
+static void forker_stop(ErlDrvData e)
+{
+ /* we probably should do something here,
+ the port has been closed by the user. */
+}
+
+static void forker_ready_input(ErlDrvData e, ErlDrvEvent fd)
+{
+ int res;
+ ErtsSysForkerProto *proto;
+
+ proto = erts_alloc(ERTS_ALC_T_DRV_CTRL_DATA, sizeof(*proto));
+
+ if ((res = read(fd, proto, sizeof(*proto))) < 0) {
+ if (errno == ERRNO_BLOCK)
+ return;
+ erl_exit(ERTS_DUMP_EXIT, "Failed to read from erl_child_setup: %d\n", errno);
+ }
+
+ if (res == 0)
+ erl_exit(ERTS_DUMP_EXIT, "erl_child_setup closed\n");
+
+ ASSERT(res == sizeof(*proto));
+
+#ifdef FORKER_PROTO_START_ACK
+ if (proto->action == ErtsSysForkerProtoAction_StartAck) {
+ /* Ideally we would like to not have to ack each Start
+ command being sent over the uds, but it would seem
+ that some operating systems (only observed on FreeBSD)
+ throw away data on the uds when the socket becomes full,
+ so we have to.
+ */
+ ErlDrvPort port_num = (ErlDrvPort)e;
+ int vlen;
+ SysIOVec *iov = driver_peekq(port_num, &vlen);
+ ErtsSysForkerProto *proto = (ErtsSysForkerProto *)iov[0].iov_base;
+
+ close(proto->u.start.fds[0]);
+ close(proto->u.start.fds[1]);
+ if (proto->u.start.fds[1] != proto->u.start.fds[2])
+ close(proto->u.start.fds[2]);
+
+ driver_deq(port_num, sizeof(*proto));
+
+ if (driver_sizeq(port_num) > 0)
+ driver_select(port_num, forker_fd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
+ } else
+#endif
+ {
+ ASSERT(proto->action == ErtsSysForkerProtoAction_SigChld);
+
+ /* ideally this would be a port_command call, but as command is
+ already used by the spawn_driver, we use control instead.
+ Note that when using erl_drv_port_control it is an asynchronous
+ control. */
+ erl_drv_port_control(proto->u.sigchld.port_id, 'S',
+ (char*)proto, sizeof(*proto));
+ }
+
+}
+
+static void forker_ready_output(ErlDrvData e, ErlDrvEvent fd)
+{
+ ErlDrvPort port_num = (ErlDrvPort)e;
+
+#ifndef FORKER_PROTO_START_ACK
+ while (driver_sizeq(port_num) > 0) {
+#endif
+ int vlen;
+ SysIOVec *iov = driver_peekq(port_num, &vlen);
+ ErtsSysForkerProto *proto = (ErtsSysForkerProto *)iov[0].iov_base;
+ ASSERT(iov[0].iov_len >= (sizeof(*proto)));
+ if (sys_uds_write(forker_fd, (char*)proto, sizeof(*proto),
+ proto->u.start.fds, 3, 0) < 0) {
+ if (errno == ERRNO_BLOCK)
+ return;
+ erl_exit(ERTS_DUMP_EXIT, "Failed to write to erl_child_setup: %d\n", errno);
+ }
+#ifndef FORKER_PROTO_START_ACK
+ close(proto->u.start.fds[0]);
+ close(proto->u.start.fds[1]);
+ if (proto->u.start.fds[1] != proto->u.start.fds[2])
+ close(proto->u.start.fds[2]);
+ driver_deq(port_num, sizeof(*proto));
+ }
+#endif
+
+ driver_select(port_num, forker_fd, ERL_DRV_WRITE, 0);
+}
+
+static ErlDrvSSizeT forker_control(ErlDrvData e, unsigned int cmd, char *buf,
+ ErlDrvSizeT len, char **rbuf, ErlDrvSizeT rlen)
+{
+ ErtsSysForkerProto *proto = (ErtsSysForkerProto *)buf;
+ ErlDrvPort port_num = (ErlDrvPort)e;
+ int res;
+
+ driver_enq(port_num, buf, len);
+ if (driver_sizeq(port_num) > sizeof(*proto)) {
+ return 0;
+ }
+
+ if ((res = sys_uds_write(forker_fd, (char*)proto, sizeof(*proto),
+ proto->u.start.fds, 3, 0)) < 0) {
+ if (errno == ERRNO_BLOCK) {
+ driver_select(port_num, forker_fd, ERL_DRV_WRITE|ERL_DRV_USE, 1);
+ return 0;
+ }
+ erl_exit(ERTS_DUMP_EXIT, "Failed to write to erl_child_setup: %d\n", errno);
+ }
+
+#ifndef FORKER_PROTO_START_ACK
+ ASSERT(res == sizeof(*proto));
+ close(proto->u.start.fds[0]);
+ close(proto->u.start.fds[1]);
+ if (proto->u.start.fds[1] != proto->u.start.fds[2])
+ close(proto->u.start.fds[2]);
+ driver_deq(port_num, sizeof(*proto));
+#endif
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-01 15:48:18 +0000