/* * This file Copyright (C) 2013-2014 Mnemosyne LLC * * It may be used under the GNU GPL versions 2 or 3 * or any future license endorsed by Mnemosyne LLC. * * $Id$ */ #ifndef TR_FILE_H #define TR_FILE_H #include #include #ifdef WIN32 #include #endif #include "error.h" #ifdef __cplusplus extern "C" { #endif /** * @addtogroup file_io File IO * @{ */ #ifndef _WIN32 /** @brief Platform-specific file descriptor type. */ typedef int tr_sys_file_t; /** @brief Platform-specific invalid file descriptor constant. */ #define TR_BAD_SYS_FILE (-1) /** @brief Platform-specific directory descriptor type. */ typedef void * tr_sys_dir_t; #else typedef HANDLE tr_sys_file_t; #define TR_BAD_SYS_FILE INVALID_HANDLE_VALUE typedef struct tr_sys_dir_win32 * tr_sys_dir_t; #endif /** @brief Platform-specific invalid directory descriptor constant. */ #define TR_BAD_SYS_DIR ((tr_sys_dir_t)NULL) typedef enum { TR_STD_SYS_FILE_IN, TR_STD_SYS_FILE_OUT, TR_STD_SYS_FILE_ERR } tr_std_sys_file_t; typedef enum { TR_SYS_FILE_READ = 1 << 0, TR_SYS_FILE_WRITE = 1 << 1, TR_SYS_FILE_CREATE = 1 << 2, TR_SYS_FILE_CREATE_NEW = 1 << 3, TR_SYS_FILE_APPEND = 1 << 4, TR_SYS_FILE_TRUNCATE = 1 << 5, TR_SYS_FILE_SEQUENTIAL = 1 << 6 } tr_sys_file_open_flags_t; typedef enum { TR_SEEK_SET, TR_SEEK_CUR, TR_SEEK_END } tr_seek_origin_t; typedef enum { TR_SYS_PATH_NO_FOLLOW = 1 << 0 } tr_sys_path_get_info_flags_t; typedef enum { TR_SYS_FILE_PREALLOC_SPARSE = 1 << 0 } tr_sys_file_preallocate_flags_t; typedef enum { TR_SYS_DIR_CREATE_PARENTS = 1 << 0 } tr_sys_dir_create_flags_t; typedef enum { TR_SYS_PATH_IS_FILE, TR_SYS_PATH_IS_DIRECTORY, TR_SYS_PATH_IS_OTHER } tr_sys_path_type_t; typedef struct tr_sys_path_info { tr_sys_path_type_t type; uint64_t size; time_t last_modified_at; } tr_sys_path_info; /** * @name Platform-specific wrapper functions * * Following functions accept paths in UTF-8 encoding and convert them to native * encoding internally if needed. * Descriptors returned (@ref tr_sys_file_t and @ref tr_sys_dir_t) may have * different type depending on platform and should generally not be passed to * native functions, but to wrapper functions instead. * * @{ */ /* Path-related wrappers */ /** * @brief Portability wrapper for `stat ()`. * * @param[in] path Path to file or directory. * @param[in] flags Combination of @ref tr_sys_path_get_info_flags_t values. * @param[out] info Result buffer. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_path_get_info (const char * path, int flags, tr_sys_path_info * info, tr_error ** error); /** * @brief Portability wrapper for `access ()`. * * @param[in] path Path to file or directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` if path exists, `false` otherwise. Note that `false` will also * be returned in case of error; if you need to distinguish the two, * check if `error` is `NULL` afterwards. */ bool tr_sys_path_exists (const char * path, tr_error ** error); /** * @brief Test to see if the two filenames point to the same file. * * @param[in] path1 Path to first file or directory. * @param[in] path2 Path to second file or directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` if two paths point to the same file or directory, `false` * otherwise. Note that `false` will also be returned in case of error; * if you need to distinguish the two, check if `error` is `NULL` * afterwards. */ bool tr_sys_path_is_same (const char * path1, const char * path2, tr_error ** error); /** * @brief Portability wrapper for `realpath ()`. * * @param[in] path Path to file or directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return Pointer to newly allocated buffer containing full path (with symbolic * links, `.` and `..` resolved) on success (use @ref tr_free to free it * when no longer needed), `NULL` otherwise (with `error` set * accordingly). */ char * tr_sys_path_resolve (const char * path, tr_error ** error); /** * @brief Portability wrapper for `basename ()`. * * @param[in] path Path to file or directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return Pointer to newly allocated buffer containing base name (last path * component; parent path removed) on success (use @ref tr_free to free * it when no longer needed), `NULL` otherwise (with `error` set * accordingly). */ char * tr_sys_path_basename (const char * path, tr_error ** error); /** * @brief Portability wrapper for `dirname ()`. * * @param[in] path Path to file or directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return Pointer to newly allocated buffer containing directory (parent path; * last path component removed) on success (use @ref tr_free to free it * when no longer needed), `NULL` otherwise (with `error` set * accordingly). */ char * tr_sys_path_dirname (const char * path, tr_error ** error); /** * @brief Portability wrapper for `rename ()`. * * @param[in] src_path Path to source file or directory. * @param[in] dst_path Path to destination file or directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). * Rename will generally only succeed if both source and destination are * on the same partition. */ bool tr_sys_path_rename (const char * src_path, const char * dst_path, tr_error ** error); /** * @brief Portability wrapper for `remove ()`. * * @param[in] path Path to file or directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). * Directory removal will only succeed if it is empty (contains no other * files and directories). */ bool tr_sys_path_remove (const char * path, tr_error ** error); /* File-related wrappers */ /** * @brief Get handle to one of standard I/O files. * * @param[in] std_file Standard file identifier. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return Opened file descriptor on success, `TR_BAD_SYS_FILE` otherwise (with * `error` set accordingly). DO NOT pass this descriptor to * @ref tr_sys_file_close (unless you know what you are doing). */ tr_sys_file_t tr_sys_file_get_std (tr_std_sys_file_t std_file, tr_error ** error); /** * @brief Portability wrapper for `open ()`. * * @param[in] path Path to file. * @param[in] flags Combination of @ref tr_sys_file_open_flags_t values. * @param[in] permissions Permissions to create file with (in case @ref TR_SYS_FILE_CREATE is used). Not used on Windows. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return Opened file descriptor on success, `TR_BAD_SYS_FILE` otherwise (with * `error` set accordingly). */ tr_sys_file_t tr_sys_file_open (const char * path, int flags, int permissions, tr_error ** error); /** * @brief Portability wrapper for `mkstemp ()`. * * @param[in,out] path_template Template path to file. Should end with at least * six 'X' characters. Upon success, trailing 'X' * characters are replaced with actual random * characters used to form a unique path to * temporary file. * @param[out] error Pointer to error object. Optional, pass `NULL` * if you are not interested in error details. * * @return Opened file descriptor on success, `TR_BAD_SYS_FILE` otherwise (with * `error` set accordingly). */ tr_sys_file_t tr_sys_file_open_temp (char * path_template, tr_error ** error); /** * @brief Portability wrapper for `close ()`. * * @param[in] handle Valid file descriptor. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_close (tr_sys_file_t handle, tr_error ** error); /** * @brief Portability wrapper for `fstat ()`. * * @param[in] handle Valid file descriptor. * @param[out] info Result buffer. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_get_info (tr_sys_file_t handle, tr_sys_path_info * info, tr_error ** error); /** * @brief Portability wrapper for `lseek ()`. * * @param[in] handle Valid file descriptor. * @param[in] offset Relative file offset in bytes to seek to. * @param[in] origin Offset origin. * @param[out] new_offset New offset in bytes from beginning of file. Optional, * pass `NULL` if you are not interested. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_seek (tr_sys_file_t handle, int64_t offset, tr_seek_origin_t origin, uint64_t * new_offset, tr_error ** error); /** * @brief Portability wrapper for `read ()`. * * @param[in] handle Valid file descriptor. * @param[out] buffer Buffer to store read data to. * @param[in] size Number of bytes to read. * @param[out] bytes_read Number of bytes actually read. Optional, pass `NULL` * if you are not interested. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_read (tr_sys_file_t handle, void * buffer, uint64_t size, uint64_t * bytes_read, tr_error ** error); /** * @brief Like `pread ()`, except that the position is undefined afterwards. * Not thread-safe. * * @param[in] handle Valid file descriptor. * @param[out] buffer Buffer to store read data to. * @param[in] size Number of bytes to read. * @param[in] offset File offset in bytes to start reading from. * @param[out] bytes_read Number of bytes actually read. Optional, pass `NULL` * if you are not interested. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_read_at (tr_sys_file_t handle, void * buffer, uint64_t size, uint64_t offset, uint64_t * bytes_read, tr_error ** error); /** * @brief Portability wrapper for `write ()`. * * @param[in] handle Valid file descriptor. * @param[in] buffer Buffer to get data being written from. * @param[in] size Number of bytes to write. * @param[out] bytes_written Number of bytes actually written. Optional, pass * `NULL` if you are not interested. * @param[out] error Pointer to error object. Optional, pass `NULL` if * you are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_write (tr_sys_file_t handle, const void * buffer, uint64_t size, uint64_t * bytes_written, tr_error ** error); /** * @brief Like `pwrite ()`, except that the position is undefined afterwards. * Not thread-safe. * * @param[in] handle Valid file descriptor. * @param[in] buffer Buffer to get data being written from. * @param[in] size Number of bytes to write. * @param[in] offset File offset in bytes to start writing from. * @param[out] bytes_written Number of bytes actually written. Optional, pass * `NULL` if you are not interested. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_write_at (tr_sys_file_t handle, const void * buffer, uint64_t size, uint64_t offset, uint64_t * bytes_written, tr_error ** error); /** * @brief Portability wrapper for `fsync ()`. * * @param[in] handle Valid file descriptor. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_flush (tr_sys_file_t handle, tr_error ** error); /** * @brief Portability wrapper for `ftruncate ()`. * * @param[in] handle Valid file descriptor. * @param[in] size Number of bytes to truncate (or extend) file to. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_truncate (tr_sys_file_t handle, uint64_t size, tr_error ** error); /** * @brief Tell system to prefetch some part of file which is to be read soon. * * @param[in] handle Valid file descriptor. * @param[in] offset Offset in file to prefetch from. * @param[in] size Number of bytes to prefetch. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_prefetch (tr_sys_file_t handle, uint64_t offset, uint64_t size, tr_error ** error); /** * @brief Preallocate file to specified size in full or sparse mode. * * @param[in] handle Valid file descriptor. * @param[in] size Number of bytes to preallocate file to. * @param[in] flags Combination of @ref tr_sys_file_preallocate_flags_t values. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_preallocate (tr_sys_file_t handle, uint64_t size, int flags, tr_error ** error); /** * @brief Portability wrapper for `mmap ()` for files. * * @param[in] handle Valid file descriptor. * @param[in] offset Offset in file to map from. * @param[in] size Number of bytes to map. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return Pointer to mapped file data on success, `NULL` otherwise (with * `error` set accordingly). */ void * tr_sys_file_map_for_reading (tr_sys_file_t handle, uint64_t offset, uint64_t size, tr_error ** error); /** * @brief Portability wrapper for `munmap ()` for files. * * @param[in] address Pointer to mapped file data. * @param[in] size Size of mapped data in bytes. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_file_unmap (const void * address, uint64_t size, tr_error ** error); /* Directory-related wrappers */ /** * @brief Portability wrapper for `getcwd ()`. * * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return Pointer to newly allocated buffer containing path to current * directory (use @ref tr_free to free it when no longer needed) on * success, `NULL` otherwise (with `error` set accordingly). */ char * tr_sys_dir_get_current (tr_error ** error); /** * @brief Like `mkdir ()`, but makes parent directories if needed. * * @param[in] path Path to directory. * @param[in] flags Combination of @ref tr_sys_dir_create_flags_t values. * @param[in] permissions Permissions to create directory with. Not used on Windows. * @param[out] error Pointer to error object. Optional, pass `NULL` if you * are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_dir_create (const char * path, int flags, int permissions, tr_error ** error); /** * @brief Portability wrapper for `mkdtemp ()`. * * @param[in,out] path_template Template path to directory. Should end with at * least six 'X' characters. Upon success, trailing * 'X' characters are replaced with actual random * characters used to form a unique path to * temporary directory. * @param[out] error Pointer to error object. Optional, pass `NULL` * if you are not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_dir_create_temp (char * path_template, tr_error ** error); /** * @brief Portability wrapper for `opendir ()`. * * @param[in] path Path to directory. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return Opened directory descriptor on success, `TR_BAD_SYS_DIR` otherwise * (with `error` set accordingly). */ tr_sys_dir_t tr_sys_dir_open (const char * path, tr_error ** error); /** * @brief Portability wrapper for `readdir ()`. * * @param[in] handle Valid directory descriptor. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return Pointer to next directory entry name (stored internally, DO NOT pass * it to @ref tr_free) on success, `NULL` otherwise (with `error` set * accordingly). Note that `NULL` will also be returned in case of end * of directory; if you need to distinguish the two, check if `error` * is `NULL` afterwards. */ const char * tr_sys_dir_read_name (tr_sys_dir_t handle, tr_error ** error); /** * @brief Portability wrapper for `closedir ()`. * * @param[in] handle Valid directory descriptor. * @param[out] error Pointer to error object. Optional, pass `NULL` if you are * not interested in error details. * * @return `True` on success, `false` otherwise (with `error` set accordingly). */ bool tr_sys_dir_close (tr_sys_dir_t handle, tr_error ** error); /** @} */ /** @} */ #ifdef __cplusplus } #endif #endif