diff options
Diffstat (limited to 'erts/emulator/nifs/common/prim_file_nif.h')
| -rw-r--r-- | erts/emulator/nifs/common/prim_file_nif.h | 240 |
1 files changed, 240 insertions, 0 deletions
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..4194cdc7d9 --- /dev/null +++ b/erts/emulator/nifs/common/prim_file_nif.h @@ -0,0 +1,240 @@ +/* + * %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% + */ + +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. */ +int efile_close(efile_data_t *d); + +/* **** **** **** **** **** **** **** **** **** **** **** **** **** **** **** */ + +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); |