/* gfileutils.c - File utility functions * * Copyright 2000 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with this library; if not, see . */ #include "config.h" #include "glibconfig.h" #include #include #include #include #include #include #include #include #include #include #ifdef G_OS_UNIX #include #endif #ifdef G_OS_WIN32 #include #include #endif /* G_OS_WIN32 */ #ifndef S_ISLNK #define S_ISLNK(x) 0 #endif #ifndef O_BINARY #define O_BINARY 0 #endif #include "gfileutils.h" #include "gstdio.h" #include "gstdioprivate.h" #include "glibintl.h" #ifdef HAVE_LINUX_MAGIC_H /* for btrfs check */ #include #include #endif /** * SECTION:fileutils * @title: File Utilities * @short_description: various file-related functions * * Do not use these APIs unless you are porting a POSIX application to Windows. * A more high-level file access API is provided as GIO — see the documentation * for #GFile. * * There is a group of functions which wrap the common POSIX functions * dealing with filenames (g_open(), g_rename(), g_mkdir(), g_stat(), * g_unlink(), g_remove(), g_fopen(), g_freopen()). The point of these * wrappers is to make it possible to handle file names with any Unicode * characters in them on Windows without having to use ifdefs and the * wide character API in the application code. * * On some Unix systems, these APIs may be defined as identical to their POSIX * counterparts. For this reason, you must check for and include the necessary * header files (such as `fcntl.h`) before using functions like g_creat(). You * must also define the relevant feature test macros. * * The pathname argument should be in the GLib file name encoding. * On POSIX this is the actual on-disk encoding which might correspond * to the locale settings of the process (or the `G_FILENAME_ENCODING` * environment variable), or not. * * On Windows the GLib file name encoding is UTF-8. Note that the * Microsoft C library does not use UTF-8, but has separate APIs for * current system code page and wide characters (UTF-16). The GLib * wrappers call the wide character API if present (on modern Windows * systems), otherwise convert to/from the system code page. * * Another group of functions allows to open and read directories * in the GLib file name encoding. These are g_dir_open(), * g_dir_read_name(), g_dir_rewind(), g_dir_close(). */ /** * GFileError: * @G_FILE_ERROR_EXIST: Operation not permitted; only the owner of * the file (or other resource) or processes with special privileges * can perform the operation. * @G_FILE_ERROR_ISDIR: File is a directory; you cannot open a directory * for writing, or create or remove hard links to it. * @G_FILE_ERROR_ACCES: Permission denied; the file permissions do not * allow the attempted operation. * @G_FILE_ERROR_NAMETOOLONG: Filename too long. * @G_FILE_ERROR_NOENT: No such file or directory. This is a "file * doesn't exist" error for ordinary files that are referenced in * contexts where they are expected to already exist. * @G_FILE_ERROR_NOTDIR: A file that isn't a directory was specified when * a directory is required. * @G_FILE_ERROR_NXIO: No such device or address. The system tried to * use the device represented by a file you specified, and it * couldn't find the device. This can mean that the device file was * installed incorrectly, or that the physical device is missing or * not correctly attached to the computer. * @G_FILE_ERROR_NODEV: The underlying file system of the specified file * does not support memory mapping. * @G_FILE_ERROR_ROFS: The directory containing the new link can't be * modified because it's on a read-only file system. * @G_FILE_ERROR_TXTBSY: Text file busy. * @G_FILE_ERROR_FAULT: You passed in a pointer to bad memory. * (GLib won't reliably return this, don't pass in pointers to bad * memory.) * @G_FILE_ERROR_LOOP: Too many levels of symbolic links were encountered * in looking up a file name. This often indicates a cycle of symbolic * links. * @G_FILE_ERROR_NOSPC: No space left on device; write operation on a * file failed because the disk is full. * @G_FILE_ERROR_NOMEM: No memory available. The system cannot allocate * more virtual memory because its capacity is full. * @G_FILE_ERROR_MFILE: The current process has too many files open and * can't open any more. Duplicate descriptors do count toward this * limit. * @G_FILE_ERROR_NFILE: There are too many distinct file openings in the * entire system. * @G_FILE_ERROR_BADF: Bad file descriptor; for example, I/O on a * descriptor that has been closed or reading from a descriptor open * only for writing (or vice versa). * @G_FILE_ERROR_INVAL: Invalid argument. This is used to indicate * various kinds of problems with passing the wrong argument to a * library function. * @G_FILE_ERROR_PIPE: Broken pipe; there is no process reading from the * other end of a pipe. Every library function that returns this * error code also generates a 'SIGPIPE' signal; this signal * terminates the program if not handled or blocked. Thus, your * program will never actually see this code unless it has handled * or blocked 'SIGPIPE'. * @G_FILE_ERROR_AGAIN: Resource temporarily unavailable; the call might * work if you try again later. * @G_FILE_ERROR_INTR: Interrupted function call; an asynchronous signal * occurred and prevented completion of the call. When this * happens, you should try the call again. * @G_FILE_ERROR_IO: Input/output error; usually used for physical read * or write errors. i.e. the disk or other physical device hardware * is returning errors. * @G_FILE_ERROR_PERM: Operation not permitted; only the owner of the * file (or other resource) or processes with special privileges can * perform the operation. * @G_FILE_ERROR_NOSYS: Function not implemented; this indicates that * the system is missing some functionality. * @G_FILE_ERROR_FAILED: Does not correspond to a UNIX error code; this * is the standard "failed for unspecified reason" error code present * in all #GError error code enumerations. Returned if no specific * code applies. * * Values corresponding to @errno codes returned from file operations * on UNIX. Unlike @errno codes, GFileError values are available on * all systems, even Windows. The exact meaning of each code depends * on what sort of file operation you were performing; the UNIX * documentation gives more details. The following error code descriptions * come from the GNU C Library manual, and are under the copyright * of that manual. * * It's not very portable to make detailed assumptions about exactly * which errors will be returned from a given operation. Some errors * don't occur on some systems, etc., sometimes there are subtle * differences in when a system will report a given error, etc. */ /** * G_FILE_ERROR: * * Error domain for file operations. Errors in this domain will * be from the #GFileError enumeration. See #GError for information * on error domains. */ /** * GFileTest: * @G_FILE_TEST_IS_REGULAR: %TRUE if the file is a regular file * (not a directory). Note that this test will also return %TRUE * if the tested file is a symlink to a regular file. * @G_FILE_TEST_IS_SYMLINK: %TRUE if the file is a symlink. * @G_FILE_TEST_IS_DIR: %TRUE if the file is a directory. * @G_FILE_TEST_IS_EXECUTABLE: %TRUE if the file is executable. * @G_FILE_TEST_EXISTS: %TRUE if the file exists. It may or may not * be a regular file. * * A test to perform on a file using g_file_test(). */ /** * g_mkdir_with_parents: * @pathname: (type filename): a pathname in the GLib file name encoding * @mode: permissions to use for newly created directories * * Create a directory if it doesn't already exist. Create intermediate * parent directories as needed, too. * * Returns: 0 if the directory already exists, or was successfully * created. Returns -1 if an error occurred, with errno set. * * Since: 2.8 */ int g_mkdir_with_parents (const gchar *pathname, int mode) { gchar *fn, *p; if (pathname == NULL || *pathname == '\0') { errno = EINVAL; return -1; } fn = g_strdup (pathname); if (g_path_is_absolute (fn)) p = (gchar *) g_path_skip_root (fn); else p = fn; do { while (*p && !G_IS_DIR_SEPARATOR (*p)) p++; if (!*p) p = NULL; else *p = '\0'; if (!g_file_test (fn, G_FILE_TEST_EXISTS)) { if (g_mkdir (fn, mode) == -1 && errno != EEXIST) { int errno_save = errno; g_free (fn); errno = errno_save; return -1; } } else if (!g_file_test (fn, G_FILE_TEST_IS_DIR)) { g_free (fn); errno = ENOTDIR; return -1; } if (p) { *p++ = G_DIR_SEPARATOR; while (*p && G_IS_DIR_SEPARATOR (*p)) p++; } } while (p); g_free (fn); return 0; } /** * g_file_test: * @filename: (type filename): a filename to test in the * GLib file name encoding * @test: bitfield of #GFileTest flags * * Returns %TRUE if any of the tests in the bitfield @test are * %TRUE. For example, `(G_FILE_TEST_EXISTS | G_FILE_TEST_IS_DIR)` * will return %TRUE if the file exists; the check whether it's a * directory doesn't matter since the existence test is %TRUE. With * the current set of available tests, there's no point passing in * more than one test at a time. * * Apart from %G_FILE_TEST_IS_SYMLINK all tests follow symbolic links, * so for a symbolic link to a regular file g_file_test() will return * %TRUE for both %G_FILE_TEST_IS_SYMLINK and %G_FILE_TEST_IS_REGULAR. * * Note, that for a dangling symbolic link g_file_test() will return * %TRUE for %G_FILE_TEST_IS_SYMLINK and %FALSE for all other flags. * * You should never use g_file_test() to test whether it is safe * to perform an operation, because there is always the possibility * of the condition changing before you actually perform the operation. * For example, you might think you could use %G_FILE_TEST_IS_SYMLINK * to know whether it is safe to write to a file without being * tricked into writing into a different location. It doesn't work! * |[ * // DON'T DO THIS * if (!g_file_test (filename, G_FILE_TEST_IS_SYMLINK)) * { * fd = g_open (filename, O_WRONLY); * // write to fd * } * ]| * * Another thing to note is that %G_FILE_TEST_EXISTS and * %G_FILE_TEST_IS_EXECUTABLE are implemented using the access() * system call. This usually doesn't matter, but if your program * is setuid or setgid it means that these tests will give you * the answer for the real user ID and group ID, rather than the * effective user ID and group ID. * * On Windows, there are no symlinks, so testing for * %G_FILE_TEST_IS_SYMLINK will always return %FALSE. Testing for * %G_FILE_TEST_IS_EXECUTABLE will just check that the file exists and * its name indicates that it is executable, checking for well-known * extensions and those listed in the `PATHEXT` environment variable. * * Returns: whether a test was %TRUE **/ gboolean g_file_test (const gchar *filename, GFileTest test) { #ifdef G_OS_WIN32 int attributes; wchar_t *wfilename; #endif g_return_val_if_fail (filename != NULL, FALSE); #ifdef G_OS_WIN32 /* stuff missing in std vc6 api */ # ifndef INVALID_FILE_ATTRIBUTES # define INVALID_FILE_ATTRIBUTES -1 # endif # ifndef FILE_ATTRIBUTE_DEVICE # define FILE_ATTRIBUTE_DEVICE 64 # endif wfilename = g_utf8_to_utf16 (filename, -1, NULL, NULL, NULL); if (wfilename == NULL) return FALSE; attributes = GetFileAttributesW (wfilename); g_free (wfilename); if (attributes == INVALID_FILE_ATTRIBUTES) return FALSE; if (test & G_FILE_TEST_EXISTS) return TRUE; if (test & G_FILE_TEST_IS_REGULAR) { if ((attributes & (FILE_ATTRIBUTE_DIRECTORY | FILE_ATTRIBUTE_DEVICE)) == 0) return TRUE; } if (test & G_FILE_TEST_IS_DIR) { if ((attributes & FILE_ATTRIBUTE_DIRECTORY) != 0) return TRUE; } /* "while" so that we can exit this "loop" with a simple "break" */ while (test & G_FILE_TEST_IS_EXECUTABLE) { const gchar *lastdot = strrchr (filename, '.'); const gchar *pathext = NULL, *p; int extlen; if (lastdot == NULL) break; if (_stricmp (lastdot, ".exe") == 0 || _stricmp (lastdot, ".cmd") == 0 || _stricmp (lastdot, ".bat") == 0 || _stricmp (lastdot, ".com") == 0) return TRUE; /* Check if it is one of the types listed in %PATHEXT% */ pathext = g_getenv ("PATHEXT"); if (pathext == NULL) break; pathext = g_utf8_casefold (pathext, -1); lastdot = g_utf8_casefold (lastdot, -1); extlen = strlen (lastdot); p = pathext; while (TRUE) { const gchar *q = strchr (p, ';'); if (q == NULL) q = p + strlen (p); if (extlen == q - p && memcmp (lastdot, p, extlen) == 0) { g_free ((gchar *) pathext); g_free ((gchar *) lastdot); return TRUE; } if (*q) p = q + 1; else break; } g_free ((gchar *) pathext); g_free ((gchar *) lastdot); break; } return FALSE; #else if ((test & G_FILE_TEST_EXISTS) && (access (filename, F_OK) == 0)) return TRUE; if ((test & G_FILE_TEST_IS_EXECUTABLE) && (access (filename, X_OK) == 0)) { if (getuid () != 0) return TRUE; /* For root, on some POSIX systems, access (filename, X_OK) * will succeed even if no executable bits are set on the * file. We fall through to a stat test to avoid that. */ } else test &= ~G_FILE_TEST_IS_EXECUTABLE; if (test & G_FILE_TEST_IS_SYMLINK) { struct stat s; if ((lstat (filename, &s) == 0) && S_ISLNK (s.st_mode)) return TRUE; } if (test & (G_FILE_TEST_IS_REGULAR | G_FILE_TEST_IS_DIR | G_FILE_TEST_IS_EXECUTABLE)) { struct stat s; if (stat (filename, &s) == 0) { if ((test & G_FILE_TEST_IS_REGULAR) && S_ISREG (s.st_mode)) return TRUE; if ((test & G_FILE_TEST_IS_DIR) && S_ISDIR (s.st_mode)) return TRUE; /* The extra test for root when access (file, X_OK) succeeds. */ if ((test & G_FILE_TEST_IS_EXECUTABLE) && ((s.st_mode & S_IXOTH) || (s.st_mode & S_IXUSR) || (s.st_mode & S_IXGRP))) return TRUE; } } return FALSE; #endif } G_DEFINE_QUARK (g-file-error-quark, g_file_error) /** * g_file_error_from_errno: * @err_no: an "errno" value * * Gets a #GFileError constant based on the passed-in @err_no. * For example, if you pass in `EEXIST` this function returns * #G_FILE_ERROR_EXIST. Unlike `errno` values, you can portably * assume that all #GFileError values will exist. * * Normally a #GFileError value goes into a #GError returned * from a function that manipulates files. So you would use * g_file_error_from_errno() when constructing a #GError. * * Returns: #GFileError corresponding to the given @errno **/ GFileError g_file_error_from_errno (gint err_no) { switch (err_no) { #ifdef EEXIST case EEXIST: return G_FILE_ERROR_EXIST; #endif #ifdef EISDIR case EISDIR: return G_FILE_ERROR_ISDIR; #endif #ifdef EACCES case EACCES: return G_FILE_ERROR_ACCES; #endif #ifdef ENAMETOOLONG case ENAMETOOLONG: return G_FILE_ERROR_NAMETOOLONG; #endif #ifdef ENOENT case ENOENT: return G_FILE_ERROR_NOENT; #endif #ifdef ENOTDIR case ENOTDIR: return G_FILE_ERROR_NOTDIR; #endif #ifdef ENXIO case ENXIO: return G_FILE_ERROR_NXIO; #endif #ifdef ENODEV case ENODEV: return G_FILE_ERROR_NODEV; #endif #ifdef EROFS case EROFS: return G_FILE_ERROR_ROFS; #endif #ifdef ETXTBSY case ETXTBSY: return G_FILE_ERROR_TXTBSY; #endif #ifdef EFAULT case EFAULT: return G_FILE_ERROR_FAULT; #endif #ifdef ELOOP case ELOOP: return G_FILE_ERROR_LOOP; #endif #ifdef ENOSPC case ENOSPC: return G_FILE_ERROR_NOSPC; #endif #ifdef ENOMEM case ENOMEM: return G_FILE_ERROR_NOMEM; #endif #ifdef EMFILE case EMFILE: return G_FILE_ERROR_MFILE; #endif #ifdef ENFILE case ENFILE: return G_FILE_ERROR_NFILE; #endif #ifdef EBADF case EBADF: return G_FILE_ERROR_BADF; #endif #ifdef EINVAL case EINVAL: return G_FILE_ERROR_INVAL; #endif #ifdef EPIPE case EPIPE: return G_FILE_ERROR_PIPE; #endif #ifdef EAGAIN case EAGAIN: return G_FILE_ERROR_AGAIN; #endif #ifdef EINTR case EINTR: return G_FILE_ERROR_INTR; #endif #ifdef EIO case EIO: return G_FILE_ERROR_IO; #endif #ifdef EPERM case EPERM: return G_FILE_ERROR_PERM; #endif #ifdef ENOSYS case ENOSYS: return G_FILE_ERROR_NOSYS; #endif default: return G_FILE_ERROR_FAILED; } } static char * format_error_message (const gchar *filename, const gchar *format_string, int saved_errno) G_GNUC_FORMAT(2); #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wformat-nonliteral" static char * format_error_message (const gchar *filename, const gchar *format_string, int saved_errno) { gchar *display_name; gchar *msg; display_name = g_filename_display_name (filename); msg = g_strdup_printf (format_string, display_name, g_strerror (saved_errno)); g_free (display_name); return msg; } #pragma GCC diagnostic pop /* format string must have two '%s': * * - the place for the filename * - the place for the strerror */ static void set_file_error (GError **error, const gchar *filename, const gchar *format_string, int saved_errno) { char *msg = format_error_message (filename, format_string, saved_errno); g_set_error_literal (error, G_FILE_ERROR, g_file_error_from_errno (saved_errno), msg); g_free (msg); } static gboolean get_contents_stdio (const gchar *filename, FILE *f, gchar **contents, gsize *length, GError **error) { gchar buf[4096]; gsize bytes; /* always <= sizeof(buf) */ gchar *str = NULL; gsize total_bytes = 0; gsize total_allocated = 0; gchar *tmp; gchar *display_filename; g_assert (f != NULL); while (!feof (f)) { gint save_errno; bytes = fread (buf, 1, sizeof (buf), f); save_errno = errno; if (total_bytes > G_MAXSIZE - bytes) goto file_too_large; /* Possibility of overflow eliminated above. */ while (total_bytes + bytes >= total_allocated) { if (str) { if (total_allocated > G_MAXSIZE / 2) goto file_too_large; total_allocated *= 2; } else { total_allocated = MIN (bytes + 1, sizeof (buf)); } tmp = g_try_realloc (str, total_allocated); if (tmp == NULL) { display_filename = g_filename_display_name (filename); g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_NOMEM, g_dngettext (GETTEXT_PACKAGE, "Could not allocate %lu byte to read file “%s”", "Could not allocate %lu bytes to read file “%s”", (gulong)total_allocated), (gulong) total_allocated, display_filename); g_free (display_filename); goto error; } str = tmp; } if (ferror (f)) { display_filename = g_filename_display_name (filename); g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (save_errno), _("Error reading file “%s”: %s"), display_filename, g_strerror (save_errno)); g_free (display_filename); goto error; } g_assert (str != NULL); memcpy (str + total_bytes, buf, bytes); total_bytes += bytes; } fclose (f); if (total_allocated == 0) { str = g_new (gchar, 1); total_bytes = 0; } str[total_bytes] = '\0'; if (length) *length = total_bytes; *contents = str; return TRUE; file_too_large: display_filename = g_filename_display_name (filename); g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED, _("File “%s” is too large"), display_filename); g_free (display_filename); error: g_free (str); fclose (f); return FALSE; } #ifndef G_OS_WIN32 static gboolean get_contents_regfile (const gchar *filename, struct stat *stat_buf, gint fd, gchar **contents, gsize *length, GError **error) { gchar *buf; gsize bytes_read; gsize size; gsize alloc_size; gchar *display_filename; size = stat_buf->st_size; alloc_size = size + 1; buf = g_try_malloc (alloc_size); if (buf == NULL) { display_filename = g_filename_display_name (filename); g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_NOMEM, g_dngettext (GETTEXT_PACKAGE, "Could not allocate %lu byte to read file “%s”", "Could not allocate %lu bytes to read file “%s”", (gulong)alloc_size), (gulong) alloc_size, display_filename); g_free (display_filename); goto error; } bytes_read = 0; while (bytes_read < size) { gssize rc; rc = read (fd, buf + bytes_read, size - bytes_read); if (rc < 0) { if (errno != EINTR) { int save_errno = errno; g_free (buf); display_filename = g_filename_display_name (filename); g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (save_errno), _("Failed to read from file “%s”: %s"), display_filename, g_strerror (save_errno)); g_free (display_filename); goto error; } } else if (rc == 0) break; else bytes_read += rc; } buf[bytes_read] = '\0'; if (length) *length = bytes_read; *contents = buf; close (fd); return TRUE; error: close (fd); return FALSE; } static gboolean get_contents_posix (const gchar *filename, gchar **contents, gsize *length, GError **error) { struct stat stat_buf; gint fd; /* O_BINARY useful on Cygwin */ fd = open (filename, O_RDONLY|O_BINARY); if (fd < 0) { int saved_errno = errno; set_file_error (error, filename, _("Failed to open file “%s”: %s"), saved_errno); return FALSE; } /* I don't think this will ever fail, aside from ENOMEM, but. */ if (fstat (fd, &stat_buf) < 0) { int saved_errno = errno; set_file_error (error, filename, _("Failed to get attributes of file “%s”: fstat() failed: %s"), saved_errno); close (fd); return FALSE; } if (stat_buf.st_size > 0 && S_ISREG (stat_buf.st_mode)) { gboolean retval = get_contents_regfile (filename, &stat_buf, fd, contents, length, error); return retval; } else { FILE *f; gboolean retval; f = fdopen (fd, "r"); if (f == NULL) { int saved_errno = errno; set_file_error (error, filename, _("Failed to open file “%s”: fdopen() failed: %s"), saved_errno); return FALSE; } retval = get_contents_stdio (filename, f, contents, length, error); return retval; } } #else /* G_OS_WIN32 */ static gboolean get_contents_win32 (const gchar *filename, gchar **contents, gsize *length, GError **error) { FILE *f; gboolean retval; f = g_fopen (filename, "rb"); if (f == NULL) { int saved_errno = errno; set_file_error (error, filename, _("Failed to open file “%s”: %s"), saved_errno); return FALSE; } retval = get_contents_stdio (filename, f, contents, length, error); return retval; } #endif /** * g_file_get_contents: * @filename: (type filename): name of a file to read contents from, in the GLib file name encoding * @contents: (out) (array length=length) (element-type guint8): location to store an allocated string, use g_free() to free * the returned string * @length: (nullable): location to store length in bytes of the contents, or %NULL * @error: return location for a #GError, or %NULL * * Reads an entire file into allocated memory, with good error * checking. * * If the call was successful, it returns %TRUE and sets @contents to the file * contents and @length to the length of the file contents in bytes. The string * stored in @contents will be nul-terminated, so for text files you can pass * %NULL for the @length argument. If the call was not successful, it returns * %FALSE and sets @error. The error domain is #G_FILE_ERROR. Possible error * codes are those in the #GFileError enumeration. In the error case, * @contents is set to %NULL and @length is set to zero. * * Returns: %TRUE on success, %FALSE if an error occurred **/ gboolean g_file_get_contents (const gchar *filename, gchar **contents, gsize *length, GError **error) { g_return_val_if_fail (filename != NULL, FALSE); g_return_val_if_fail (contents != NULL, FALSE); *contents = NULL; if (length) *length = 0; #ifdef G_OS_WIN32 return get_contents_win32 (filename, contents, length, error); #else return get_contents_posix (filename, contents, length, error); #endif } static gboolean rename_file (const char *old_name, const char *new_name, GError **err) { errno = 0; if (g_rename (old_name, new_name) == -1) { int save_errno = errno; gchar *display_old_name = g_filename_display_name (old_name); gchar *display_new_name = g_filename_display_name (new_name); g_set_error (err, G_FILE_ERROR, g_file_error_from_errno (save_errno), _("Failed to rename file “%s” to “%s”: g_rename() failed: %s"), display_old_name, display_new_name, g_strerror (save_errno)); g_free (display_old_name); g_free (display_new_name); return FALSE; } return TRUE; } static gchar * write_to_temp_file (const gchar *contents, gssize length, const gchar *dest_file, GError **err) { gchar *tmp_name; gchar *retval; gint fd; retval = NULL; tmp_name = g_strdup_printf ("%s.XXXXXX", dest_file); errno = 0; fd = g_mkstemp_full (tmp_name, O_RDWR | O_BINARY, 0666); if (fd == -1) { int saved_errno = errno; set_file_error (err, tmp_name, _("Failed to create file “%s”: %s"), saved_errno); goto out; } #ifdef HAVE_FALLOCATE if (length > 0) { /* We do this on a 'best effort' basis... It may not be supported * on the underlying filesystem. */ (void) fallocate (fd, 0, 0, length); } #endif while (length > 0) { gssize s; s = write (fd, contents, length); if (s < 0) { int saved_errno = errno; if (saved_errno == EINTR) continue; set_file_error (err, tmp_name, _("Failed to write file “%s”: write() failed: %s"), saved_errno); close (fd); g_unlink (tmp_name); goto out; } g_assert (s <= length); contents += s; length -= s; } #ifdef BTRFS_SUPER_MAGIC { struct statfs buf; /* On Linux, on btrfs, skip the fsync since rename-over-existing is * guaranteed to be atomic and this is the only case in which we * would fsync() anyway. */ if (fstatfs (fd, &buf) == 0 && buf.f_type == BTRFS_SUPER_MAGIC) goto no_fsync; } #endif #ifdef HAVE_FSYNC { struct stat statbuf; errno = 0; /* If the final destination exists and is > 0 bytes, we want to sync the * newly written file to ensure the data is on disk when we rename over * the destination. Otherwise if we get a system crash we can lose both * the new and the old file on some filesystems. (I.E. those that don't * guarantee the data is written to the disk before the metadata.) */ if (g_lstat (dest_file, &statbuf) == 0 && statbuf.st_size > 0 && fsync (fd) != 0) { int saved_errno = errno; set_file_error (err, tmp_name, _("Failed to write file “%s”: fsync() failed: %s"), saved_errno); close (fd); g_unlink (tmp_name); goto out; } } #endif #ifdef BTRFS_SUPER_MAGIC no_fsync: #endif errno = 0; if (!g_close (fd, err)) { g_unlink (tmp_name); goto out; } retval = g_strdup (tmp_name); out: g_free (tmp_name); return retval; } /** * g_file_set_contents: * @filename: (type filename): name of a file to write @contents to, in the GLib file name * encoding * @contents: (array length=length) (element-type guint8): string to write to the file * @length: length of @contents, or -1 if @contents is a nul-terminated string * @error: return location for a #GError, or %NULL * * Writes all of @contents to a file named @filename, with good error checking. * If a file called @filename already exists it will be overwritten. * * This write is atomic in the sense that it is first written to a temporary * file which is then renamed to the final name. Notes: * * - On UNIX, if @filename already exists hard links to @filename will break. * Also since the file is recreated, existing permissions, access control * lists, metadata etc. may be lost. If @filename is a symbolic link, * the link itself will be replaced, not the linked file. * * - On Windows renaming a file will not remove an existing file with the * new name, so on Windows there is a race condition between the existing * file being removed and the temporary file being renamed. * * - On Windows there is no way to remove a file that is open to some * process, or mapped into memory. Thus, this function will fail if * @filename already exists and is open. * * If the call was successful, it returns %TRUE. If the call was not successful, * it returns %FALSE and sets @error. The error domain is #G_FILE_ERROR. * Possible error codes are those in the #GFileError enumeration. * * Note that the name for the temporary file is constructed by appending up * to 7 characters to @filename. * * Returns: %TRUE on success, %FALSE if an error occurred * * Since: 2.8 */ gboolean g_file_set_contents (const gchar *filename, const gchar *contents, gssize length, GError **error) { gchar *tmp_filename; gboolean retval; GError *rename_error = NULL; g_return_val_if_fail (filename != NULL, FALSE); g_return_val_if_fail (error == NULL || *error == NULL, FALSE); g_return_val_if_fail (contents != NULL || length == 0, FALSE); g_return_val_if_fail (length >= -1, FALSE); if (length == -1) length = strlen (contents); tmp_filename = write_to_temp_file (contents, length, filename, error); if (!tmp_filename) { retval = FALSE; goto out; } if (!rename_file (tmp_filename, filename, &rename_error)) { #ifndef G_OS_WIN32 g_unlink (tmp_filename); g_propagate_error (error, rename_error); retval = FALSE; goto out; #else /* G_OS_WIN32 */ /* Renaming failed, but on Windows this may just mean * the file already exists. So if the target file * exists, try deleting it and do the rename again. */ if (!g_file_test (filename, G_FILE_TEST_EXISTS)) { g_unlink (tmp_filename); g_propagate_error (error, rename_error); retval = FALSE; goto out; } g_error_free (rename_error); if (g_unlink (filename) == -1) { int saved_errno = errno; set_file_error (error, filename, _("Existing file “%s” could not be removed: g_unlink() failed: %s"), saved_errno); g_unlink (tmp_filename); retval = FALSE; goto out; } if (!rename_file (tmp_filename, filename, error)) { g_unlink (tmp_filename); retval = FALSE; goto out; } #endif } retval = TRUE; out: g_free (tmp_filename); return retval; } /* * get_tmp_file based on the mkstemp implementation from the GNU C library. * Copyright (C) 1991,92,93,94,95,96,97,98,99 Free Software Foundation, Inc. */ typedef gint (*GTmpFileCallback) (const gchar *, gint, gint); static gint get_tmp_file (gchar *tmpl, GTmpFileCallback f, int flags, int mode) { char *XXXXXX; int count, fd; static const char letters[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; static const int NLETTERS = sizeof (letters) - 1; glong value; GTimeVal tv; static int counter = 0; g_return_val_if_fail (tmpl != NULL, -1); /* find the last occurrence of "XXXXXX" */ XXXXXX = g_strrstr (tmpl, "XXXXXX"); if (!XXXXXX || strncmp (XXXXXX, "XXXXXX", 6)) { errno = EINVAL; return -1; } /* Get some more or less random data. */ g_get_current_time (&tv); value = (tv.tv_usec ^ tv.tv_sec) + counter++; for (count = 0; count < 100; value += 7777, ++count) { glong v = value; /* Fill in the random bits. */ XXXXXX[0] = letters[v % NLETTERS]; v /= NLETTERS; XXXXXX[1] = letters[v % NLETTERS]; v /= NLETTERS; XXXXXX[2] = letters[v % NLETTERS]; v /= NLETTERS; XXXXXX[3] = letters[v % NLETTERS]; v /= NLETTERS; XXXXXX[4] = letters[v % NLETTERS]; v /= NLETTERS; XXXXXX[5] = letters[v % NLETTERS]; fd = f (tmpl, flags, mode); if (fd >= 0) return fd; else if (errno != EEXIST) /* Any other error will apply also to other names we might * try, and there are 2^32 or so of them, so give up now. */ return -1; } /* We got out of the loop because we ran out of combinations to try. */ errno = EEXIST; return -1; } /* Some GTmpFileCallback implementations. * * Note: we cannot use open() or g_open() directly because even though * they appear compatible, they may be vararg functions and calling * varargs functions through a non-varargs type is undefined. */ static gint wrap_g_mkdir (const gchar *filename, int flags G_GNUC_UNUSED, int mode) { /* tmpl is in UTF-8 on Windows, thus use g_mkdir() */ return g_mkdir (filename, mode); } static gint wrap_g_open (const gchar *filename, int flags, int mode) { return g_open (filename, flags, mode); } /** * g_mkdtemp_full: (skip) * @tmpl: (type filename): template directory name * @mode: permissions to create the temporary directory with * * Creates a temporary directory. See the mkdtemp() documentation * on most UNIX-like systems. * * The parameter is a string that should follow the rules for * mkdtemp() templates, i.e. contain the string "XXXXXX". * g_mkdtemp_full() is slightly more flexible than mkdtemp() in that the * sequence does not have to occur at the very end of the template * and you can pass a @mode. The X string will be modified to form * the name of a directory that didn't exist. The string should be * in the GLib file name encoding. Most importantly, on Windows it * should be in UTF-8. * * If you are going to be creating a temporary directory inside the * directory returned by g_get_tmp_dir(), you might want to use * g_dir_make_tmp() instead. * * Returns: (nullable) (type filename): A pointer to @tmpl, which has been * modified to hold the directory name. In case of errors, %NULL is * returned, and %errno will be set. * * Since: 2.30 */ gchar * g_mkdtemp_full (gchar *tmpl, gint mode) { if (get_tmp_file (tmpl, wrap_g_mkdir, 0, mode) == -1) return NULL; else return tmpl; } /** * g_mkdtemp: (skip) * @tmpl: (type filename): template directory name * * Creates a temporary directory. See the mkdtemp() documentation * on most UNIX-like systems. * * The parameter is a string that should follow the rules for * mkdtemp() templates, i.e. contain the string "XXXXXX". * g_mkdtemp() is slightly more flexible than mkdtemp() in that the * sequence does not have to occur at the very end of the template. * The X string will be modified to form the name of a directory that * didn't exist. * The string should be in the GLib file name encoding. Most importantly, * on Windows it should be in UTF-8. * * If you are going to be creating a temporary directory inside the * directory returned by g_get_tmp_dir(), you might want to use * g_dir_make_tmp() instead. * * Returns: (nullable) (type filename): A pointer to @tmpl, which has been * modified to hold the directory name. In case of errors, %NULL is * returned and %errno will be set. * * Since: 2.30 */ gchar * g_mkdtemp (gchar *tmpl) { return g_mkdtemp_full (tmpl, 0700); } /** * g_mkstemp_full: (skip) * @tmpl: (type filename): template filename * @flags: flags to pass to an open() call in addition to O_EXCL * and O_CREAT, which are passed automatically * @mode: permissions to create the temporary file with * * Opens a temporary file. See the mkstemp() documentation * on most UNIX-like systems. * * The parameter is a string that should follow the rules for * mkstemp() templates, i.e. contain the string "XXXXXX". * g_mkstemp_full() is slightly more flexible than mkstemp() * in that the sequence does not have to occur at the very end of the * template and you can pass a @mode and additional @flags. The X * string will be modified to form the name of a file that didn't exist. * The string should be in the GLib file name encoding. Most importantly, * on Windows it should be in UTF-8. * * Returns: A file handle (as from open()) to the file * opened for reading and writing. The file handle should be * closed with close(). In case of errors, -1 is returned * and %errno will be set. * * Since: 2.22 */ gint g_mkstemp_full (gchar *tmpl, gint flags, gint mode) { /* tmpl is in UTF-8 on Windows, thus use g_open() */ return get_tmp_file (tmpl, wrap_g_open, flags | O_CREAT | O_EXCL, mode); } /** * g_mkstemp: (skip) * @tmpl: (type filename): template filename * * Opens a temporary file. See the mkstemp() documentation * on most UNIX-like systems. * * The parameter is a string that should follow the rules for * mkstemp() templates, i.e. contain the string "XXXXXX". * g_mkstemp() is slightly more flexible than mkstemp() in that the * sequence does not have to occur at the very end of the template. * The X string will be modified to form the name of a file that * didn't exist. The string should be in the GLib file name encoding. * Most importantly, on Windows it should be in UTF-8. * * Returns: A file handle (as from open()) to the file * opened for reading and writing. The file is opened in binary * mode on platforms where there is a difference. The file handle * should be closed with close(). In case of errors, -1 is * returned and %errno will be set. */ gint g_mkstemp (gchar *tmpl) { return g_mkstemp_full (tmpl, O_RDWR | O_BINARY, 0600); } static gint g_get_tmp_name (const gchar *tmpl, gchar **name_used, GTmpFileCallback f, gint flags, gint mode, GError **error) { int retval; const char *tmpdir; const char *sep; char *fulltemplate; const char *slash; if (tmpl == NULL) tmpl = ".XXXXXX"; if ((slash = strchr (tmpl, G_DIR_SEPARATOR)) != NULL #ifdef G_OS_WIN32 || (strchr (tmpl, '/') != NULL && (slash = "/")) #endif ) { gchar *display_tmpl = g_filename_display_name (tmpl); char c[2]; c[0] = *slash; c[1] = '\0'; g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED, _("Template “%s” invalid, should not contain a “%s”"), display_tmpl, c); g_free (display_tmpl); return -1; } if (strstr (tmpl, "XXXXXX") == NULL) { gchar *display_tmpl = g_filename_display_name (tmpl); g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED, _("Template “%s” doesn’t contain XXXXXX"), display_tmpl); g_free (display_tmpl); return -1; } tmpdir = g_get_tmp_dir (); if (G_IS_DIR_SEPARATOR (tmpdir [strlen (tmpdir) - 1])) sep = ""; else sep = G_DIR_SEPARATOR_S; fulltemplate = g_strconcat (tmpdir, sep, tmpl, NULL); retval = get_tmp_file (fulltemplate, f, flags, mode); if (retval == -1) { int saved_errno = errno; set_file_error (error, fulltemplate, _("Failed to create file “%s”: %s"), saved_errno); g_free (fulltemplate); return -1; } *name_used = fulltemplate; return retval; } /** * g_file_open_tmp: * @tmpl: (type filename) (nullable): Template for file name, as in * g_mkstemp(), basename only, or %NULL for a default template * @name_used: (out) (type filename): location to store actual name used, * or %NULL * @error: return location for a #GError * * Opens a file for writing in the preferred directory for temporary * files (as returned by g_get_tmp_dir()). * * @tmpl should be a string in the GLib file name encoding containing * a sequence of six 'X' characters, as the parameter to g_mkstemp(). * However, unlike these functions, the template should only be a * basename, no directory components are allowed. If template is * %NULL, a default template is used. * * Note that in contrast to g_mkstemp() (and mkstemp()) @tmpl is not * modified, and might thus be a read-only literal string. * * Upon success, and if @name_used is non-%NULL, the actual name used * is returned in @name_used. This string should be freed with g_free() * when not needed any longer. The returned name is in the GLib file * name encoding. * * Returns: A file handle (as from open()) to the file opened for * reading and writing. The file is opened in binary mode on platforms * where there is a difference. The file handle should be closed with * close(). In case of errors, -1 is returned and @error will be set. */ gint g_file_open_tmp (const gchar *tmpl, gchar **name_used, GError **error) { gchar *fulltemplate; gint result; g_return_val_if_fail (error == NULL || *error == NULL, -1); result = g_get_tmp_name (tmpl, &fulltemplate, wrap_g_open, O_CREAT | O_EXCL | O_RDWR | O_BINARY, 0600, error); if (result != -1) { if (name_used) *name_used = fulltemplate; else g_free (fulltemplate); } return result; } /** * g_dir_make_tmp: * @tmpl: (type filename) (nullable): Template for directory name, * as in g_mkdtemp(), basename only, or %NULL for a default template * @error: return location for a #GError * * Creates a subdirectory in the preferred directory for temporary * files (as returned by g_get_tmp_dir()). * * @tmpl should be a string in the GLib file name encoding containing * a sequence of six 'X' characters, as the parameter to g_mkstemp(). * However, unlike these functions, the template should only be a * basename, no directory components are allowed. If template is * %NULL, a default template is used. * * Note that in contrast to g_mkdtemp() (and mkdtemp()) @tmpl is not * modified, and might thus be a read-only literal string. * * Returns: (type filename): The actual name used. This string * should be freed with g_free() when not needed any longer and is * is in the GLib file name encoding. In case of errors, %NULL is * returned and @error will be set. * * Since: 2.30 */ gchar * g_dir_make_tmp (const gchar *tmpl, GError **error) { gchar *fulltemplate; g_return_val_if_fail (error == NULL || *error == NULL, NULL); if (g_get_tmp_name (tmpl, &fulltemplate, wrap_g_mkdir, 0, 0700, error) == -1) return NULL; else return fulltemplate; } static gchar * g_build_path_va (const gchar *separator, const gchar *first_element, va_list *args, gchar **str_array) { GString *result; gint separator_len = strlen (separator); gboolean is_first = TRUE; gboolean have_leading = FALSE; const gchar *single_element = NULL; const gchar *next_element; const gchar *last_trailing = NULL; gint i = 0; result = g_string_new (NULL); if (str_array) next_element = str_array[i++]; else next_element = first_element; while (TRUE) { const gchar *element; const gchar *start; const gchar *end; if (next_element) { element = next_element; if (str_array) next_element = str_array[i++]; else next_element = va_arg (*args, gchar *); } else break; /* Ignore empty elements */ if (!*element) continue; start = element; if (separator_len) { while (strncmp (start, separator, separator_len) == 0) start += separator_len; } end = start + strlen (start); if (separator_len) { while (end >= start + separator_len && strncmp (end - separator_len, separator, separator_len) == 0) end -= separator_len; last_trailing = end; while (last_trailing >= element + separator_len && strncmp (last_trailing - separator_len, separator, separator_len) == 0) last_trailing -= separator_len; if (!have_leading) { /* If the leading and trailing separator strings are in the * same element and overlap, the result is exactly that element */ if (last_trailing <= start) single_element = element; g_string_append_len (result, element, start - element); have_leading = TRUE; } else single_element = NULL; } if (end == start) continue; if (!is_first) g_string_append (result, separator); g_string_append_len (result, start, end - start); is_first = FALSE; } if (single_element) { g_string_free (result, TRUE); return g_strdup (single_element); } else { if (last_trailing) g_string_append (result, last_trailing); return g_string_free (result, FALSE); } } /** * g_build_pathv: * @separator: a string used to separator the elements of the path. * @args: (array zero-terminated=1) (element-type filename): %NULL-terminated * array of strings containing the path elements. * * Behaves exactly like g_build_path(), but takes the path elements * as a string array, instead of varargs. This function is mainly * meant for language bindings. * * Returns: (type filename): a newly-allocated string that must be freed * with g_free(). * * Since: 2.8 */ gchar * g_build_pathv (const gchar *separator, gchar **args) { if (!args) return NULL; return g_build_path_va (separator, NULL, NULL, args); } /** * g_build_path: * @separator: (type filename): a string used to separator the elements of the path. * @first_element: (type filename): the first element in the path * @...: remaining elements in path, terminated by %NULL * * Creates a path from a series of elements using @separator as the * separator between elements. At the boundary between two elements, * any trailing occurrences of separator in the first element, or * leading occurrences of separator in the second element are removed * and exactly one copy of the separator is inserted. * * Empty elements are ignored. * * The number of leading copies of the separator on the result is * the same as the number of leading copies of the separator on * the first non-empty element. * * The number of trailing copies of the separator on the result is * the same as the number of trailing copies of the separator on * the last non-empty element. (Determination of the number of * trailing copies is done without stripping leading copies, so * if the separator is `ABA`, then `ABABA` has 1 trailing copy.) * * However, if there is only a single non-empty element, and there * are no characters in that element not part of the leading or * trailing separators, then the result is exactly the original value * of that element. * * Other than for determination of the number of leading and trailing * copies of the separator, elements consisting only of copies * of the separator are ignored. * * Returns: (type filename): a newly-allocated string that must be freed with * g_free(). **/ gchar * g_build_path (const gchar *separator, const gchar *first_element, ...) { gchar *str; va_list args; g_return_val_if_fail (separator != NULL, NULL); va_start (args, first_element); str = g_build_path_va (separator, first_element, &args, NULL); va_end (args); return str; } #ifdef G_OS_WIN32 static gchar * g_build_pathname_va (const gchar *first_element, va_list *args, gchar **str_array) { /* Code copied from g_build_pathv(), and modified to use two * alternative single-character separators. */ GString *result; gboolean is_first = TRUE; gboolean have_leading = FALSE; const gchar *single_element = NULL; const gchar *next_element; const gchar *last_trailing = NULL; gchar current_separator = '\\'; gint i = 0; result = g_string_new (NULL); if (str_array) next_element = str_array[i++]; else next_element = first_element; while (TRUE) { const gchar *element; const gchar *start; const gchar *end; if (next_element) { element = next_element; if (str_array) next_element = str_array[i++]; else next_element = va_arg (*args, gchar *); } else break; /* Ignore empty elements */ if (!*element) continue; start = element; if (TRUE) { while (start && (*start == '\\' || *start == '/')) { current_separator = *start; start++; } } end = start + strlen (start); if (TRUE) { while (end >= start + 1 && (end[-1] == '\\' || end[-1] == '/')) { current_separator = end[-1]; end--; } last_trailing = end; while (last_trailing >= element + 1 && (last_trailing[-1] == '\\' || last_trailing[-1] == '/')) last_trailing--; if (!have_leading) { /* If the leading and trailing separator strings are in the * same element and overlap, the result is exactly that element */ if (last_trailing <= start) single_element = element; g_string_append_len (result, element, start - element); have_leading = TRUE; } else single_element = NULL; } if (end == start) continue; if (!is_first) g_string_append_len (result, ¤t_separator, 1); g_string_append_len (result, start, end - start); is_first = FALSE; } if (single_element) { g_string_free (result, TRUE); return g_strdup (single_element); } else { if (last_trailing) g_string_append (result, last_trailing); return g_string_free (result, FALSE); } } #endif /** * g_build_filenamev: * @args: (array zero-terminated=1) (element-type filename): %NULL-terminated * array of strings containing the path elements. * * Behaves exactly like g_build_filename(), but takes the path elements * as a string array, instead of varargs. This function is mainly * meant for language bindings. * * Returns: (type filename): a newly-allocated string that must be freed * with g_free(). * * Since: 2.8 */ gchar * g_build_filenamev (gchar **args) { gchar *str; #ifndef G_OS_WIN32 str = g_build_path_va (G_DIR_SEPARATOR_S, NULL, NULL, args); #else str = g_build_pathname_va (NULL, NULL, args); #endif return str; } /** * g_build_filename: * @first_element: (type filename): the first element in the path * @...: remaining elements in path, terminated by %NULL * * Creates a filename from a series of elements using the correct * separator for filenames. * * On Unix, this function behaves identically to `g_build_path * (G_DIR_SEPARATOR_S, first_element, ....)`. * * On Windows, it takes into account that either the backslash * (`\` or slash (`/`) can be used as separator in filenames, but * otherwise behaves as on UNIX. When file pathname separators need * to be inserted, the one that last previously occurred in the * parameters (reading from left to right) is used. * * No attempt is made to force the resulting filename to be an absolute * path. If the first element is a relative path, the result will * be a relative path. * * Returns: (type filename): a newly-allocated string that must be freed with * g_free(). **/ gchar * g_build_filename (const gchar *first_element, ...) { gchar *str; va_list args; va_start (args, first_element); #ifndef G_OS_WIN32 str = g_build_path_va (G_DIR_SEPARATOR_S, first_element, &args, NULL); #else str = g_build_pathname_va (first_element, &args, NULL); #endif va_end (args); return str; } /** * g_file_read_link: * @filename: (type filename): the symbolic link * @error: return location for a #GError * * Reads the contents of the symbolic link @filename like the POSIX * readlink() function. The returned string is in the encoding used * for filenames. Use g_filename_to_utf8() to convert it to UTF-8. * * Returns: (type filename): A newly-allocated string with the contents of * the symbolic link, or %NULL if an error occurred. * * Since: 2.4 */ gchar * g_file_read_link (const gchar *filename, GError **error) { #if defined (HAVE_READLINK) || defined (G_OS_WIN32) gchar *buffer; size_t size; gssize read_size; g_return_val_if_fail (filename != NULL, NULL); g_return_val_if_fail (error == NULL || *error == NULL, NULL); size = 256; buffer = g_malloc (size); while (TRUE) { #ifndef G_OS_WIN32 read_size = readlink (filename, buffer, size); #else read_size = g_win32_readlink_utf8 (filename, buffer, size); #endif if (read_size < 0) { int saved_errno = errno; set_file_error (error, filename, _("Failed to read the symbolic link “%s”: %s"), saved_errno); g_free (buffer); return NULL; } if ((size_t) read_size < size) { buffer[read_size] = 0; return buffer; } size *= 2; buffer = g_realloc (buffer, size); } #else g_return_val_if_fail (filename != NULL, NULL); g_return_val_if_fail (error == NULL || *error == NULL, NULL); g_set_error_literal (error, G_FILE_ERROR, G_FILE_ERROR_INVAL, _("Symbolic links not supported")); return NULL; #endif } /** * g_path_is_absolute: * @file_name: (type filename): a file name * * Returns %TRUE if the given @file_name is an absolute file name. * Note that this is a somewhat vague concept on Windows. * * On POSIX systems, an absolute file name is well-defined. It always * starts from the single root directory. For example "/usr/local". * * On Windows, the concepts of current drive and drive-specific * current directory introduce vagueness. This function interprets as * an absolute file name one that either begins with a directory * separator such as "\Users\tml" or begins with the root on a drive, * for example "C:\Windows". The first case also includes UNC paths * such as "\\\\myserver\docs\foo". In all cases, either slashes or * backslashes are accepted. * * Note that a file name relative to the current drive root does not * truly specify a file uniquely over time and across processes, as * the current drive is a per-process value and can be changed. * * File names relative the current directory on some specific drive, * such as "D:foo/bar", are not interpreted as absolute by this * function, but they obviously are not relative to the normal current * directory as returned by getcwd() or g_get_current_dir() * either. Such paths should be avoided, or need to be handled using * Windows-specific code. * * Returns: %TRUE if @file_name is absolute */ gboolean g_path_is_absolute (const gchar *file_name) { g_return_val_if_fail (file_name != NULL, FALSE); if (G_IS_DIR_SEPARATOR (file_name[0])) return TRUE; #ifdef G_OS_WIN32 /* Recognize drive letter on native Windows */ if (g_ascii_isalpha (file_name[0]) && file_name[1] == ':' && G_IS_DIR_SEPARATOR (file_name[2])) return TRUE; #endif return FALSE; } /** * g_path_skip_root: * @file_name: (type filename): a file name * * Returns a pointer into @file_name after the root component, * i.e. after the "/" in UNIX or "C:\" under Windows. If @file_name * is not an absolute path it returns %NULL. * * Returns: (type filename) (nullable): a pointer into @file_name after the * root component */ const gchar * g_path_skip_root (const gchar *file_name) { g_return_val_if_fail (file_name != NULL, NULL); #ifdef G_PLATFORM_WIN32 /* Skip \\server\share or //server/share */ if (G_IS_DIR_SEPARATOR (file_name[0]) && G_IS_DIR_SEPARATOR (file_name[1]) && file_name[2] && !G_IS_DIR_SEPARATOR (file_name[2])) { gchar *p; p = strchr (file_name + 2, G_DIR_SEPARATOR); #ifdef G_OS_WIN32 { gchar *q; q = strchr (file_name + 2, '/'); if (p == NULL || (q != NULL && q < p)) p = q; } #endif if (p && p > file_name + 2 && p[1]) { file_name = p + 1; while (file_name[0] && !G_IS_DIR_SEPARATOR (file_name[0])) file_name++; /* Possibly skip a backslash after the share name */ if (G_IS_DIR_SEPARATOR (file_name[0])) file_name++; return (gchar *)file_name; } } #endif /* Skip initial slashes */ if (G_IS_DIR_SEPARATOR (file_name[0])) { while (G_IS_DIR_SEPARATOR (file_name[0])) file_name++; return (gchar *)file_name; } #ifdef G_OS_WIN32 /* Skip X:\ */ if (g_ascii_isalpha (file_name[0]) && file_name[1] == ':' && G_IS_DIR_SEPARATOR (file_name[2])) return (gchar *)file_name + 3; #endif return NULL; } /** * g_basename: * @file_name: (type filename): the name of the file * * Gets the name of the file without any leading directory * components. It returns a pointer into the given file name * string. * * Returns: (type filename): the name of the file without any leading * directory components * * Deprecated:2.2: Use g_path_get_basename() instead, but notice * that g_path_get_basename() allocates new memory for the * returned string, unlike this function which returns a pointer * into the argument. */ const gchar * g_basename (const gchar *file_name) { gchar *base; g_return_val_if_fail (file_name != NULL, NULL); base = strrchr (file_name, G_DIR_SEPARATOR); #ifdef G_OS_WIN32 { gchar *q; q = strrchr (file_name, '/'); if (base == NULL || (q != NULL && q > base)) base = q; } #endif if (base) return base + 1; #ifdef G_OS_WIN32 if (g_ascii_isalpha (file_name[0]) && file_name[1] == ':') return (gchar*) file_name + 2; #endif return (gchar*) file_name; } /** * g_path_get_basename: * @file_name: (type filename): the name of the file * * Gets the last component of the filename. * * If @file_name ends with a directory separator it gets the component * before the last slash. If @file_name consists only of directory * separators (and on Windows, possibly a drive letter), a single * separator is returned. If @file_name is empty, it gets ".". * * Returns: (type filename): a newly allocated string containing the last * component of the filename */ gchar * g_path_get_basename (const gchar *file_name) { gssize base; gssize last_nonslash; gsize len; gchar *retval; g_return_val_if_fail (file_name != NULL, NULL); if (file_name[0] == '\0') return g_strdup ("."); last_nonslash = strlen (file_name) - 1; while (last_nonslash >= 0 && G_IS_DIR_SEPARATOR (file_name [last_nonslash])) last_nonslash--; if (last_nonslash == -1) /* string only containing slashes */ return g_strdup (G_DIR_SEPARATOR_S); #ifdef G_OS_WIN32 if (last_nonslash == 1 && g_ascii_isalpha (file_name[0]) && file_name[1] == ':') /* string only containing slashes and a drive */ return g_strdup (G_DIR_SEPARATOR_S); #endif base = last_nonslash; while (base >=0 && !G_IS_DIR_SEPARATOR (file_name [base])) base--; #ifdef G_OS_WIN32 if (base == -1 && g_ascii_isalpha (file_name[0]) && file_name[1] == ':') base = 1; #endif /* G_OS_WIN32 */ len = last_nonslash - base; retval = g_malloc (len + 1); memcpy (retval, file_name + base + 1, len); retval [len] = '\0'; return retval; } /** * g_dirname: * @file_name: (type filename): the name of the file * * Gets the directory components of a file name. * * If the file name has no directory components "." is returned. * The returned string should be freed when no longer needed. * * Returns: (type filename): the directory components of the file * * Deprecated: use g_path_get_dirname() instead */ /** * g_path_get_dirname: * @file_name: (type filename): the name of the file * * Gets the directory components of a file name. * * If the file name has no directory components "." is returned. * The returned string should be freed when no longer needed. * * Returns: (type filename): the directory components of the file */ gchar * g_path_get_dirname (const gchar *file_name) { gchar *base; gsize len; g_return_val_if_fail (file_name != NULL, NULL); base = strrchr (file_name, G_DIR_SEPARATOR); #ifdef G_OS_WIN32 { gchar *q; q = strrchr (file_name, '/'); if (base == NULL || (q != NULL && q > base)) base = q; } #endif if (!base) { #ifdef G_OS_WIN32 if (g_ascii_isalpha (file_name[0]) && file_name[1] == ':') { gchar drive_colon_dot[4]; drive_colon_dot[0] = file_name[0]; drive_colon_dot[1] = ':'; drive_colon_dot[2] = '.'; drive_colon_dot[3] = '\0'; return g_strdup (drive_colon_dot); } #endif return g_strdup ("."); } while (base > file_name && G_IS_DIR_SEPARATOR (*base)) base--; #ifdef G_OS_WIN32 /* base points to the char before the last slash. * * In case file_name is the root of a drive (X:\) or a child of the * root of a drive (X:\foo), include the slash. * * In case file_name is the root share of an UNC path * (\\server\share), add a slash, returning \\server\share\ . * * In case file_name is a direct child of a share in an UNC path * (\\server\share\foo), include the slash after the share name, * returning \\server\share\ . */ if (base == file_name + 1 && g_ascii_isalpha (file_name[0]) && file_name[1] == ':') base++; else if (G_IS_DIR_SEPARATOR (file_name[0]) && G_IS_DIR_SEPARATOR (file_name[1]) && file_name[2] && !G_IS_DIR_SEPARATOR (file_name[2]) && base >= file_name + 2) { const gchar *p = file_name + 2; while (*p && !G_IS_DIR_SEPARATOR (*p)) p++; if (p == base + 1) { len = (guint) strlen (file_name) + 1; base = g_new (gchar, len + 1); strcpy (base, file_name); base[len-1] = G_DIR_SEPARATOR; base[len] = 0; return base; } if (G_IS_DIR_SEPARATOR (*p)) { p++; while (*p && !G_IS_DIR_SEPARATOR (*p)) p++; if (p == base + 1) base++; } } #endif len = (guint) 1 + base - file_name; base = g_new (gchar, len + 1); memmove (base, file_name, len); base[len] = 0; return base; } #if defined(MAXPATHLEN) #define G_PATH_LENGTH MAXPATHLEN #elif defined(PATH_MAX) #define G_PATH_LENGTH PATH_MAX #elif defined(_PC_PATH_MAX) #define G_PATH_LENGTH sysconf(_PC_PATH_MAX) #else #define G_PATH_LENGTH 2048 #endif /** * g_get_current_dir: * * Gets the current directory. * * The returned string should be freed when no longer needed. * The encoding of the returned string is system defined. * On Windows, it is always UTF-8. * * Since GLib 2.40, this function will return the value of the "PWD" * environment variable if it is set and it happens to be the same as * the current directory. This can make a difference in the case that * the current directory is the target of a symbolic link. * * Returns: (type filename): the current directory */ gchar * g_get_current_dir (void) { #ifdef G_OS_WIN32 gchar *dir = NULL; wchar_t dummy[2], *wdir; int len; len = GetCurrentDirectoryW (2, dummy); wdir = g_new (wchar_t, len); if (GetCurrentDirectoryW (len, wdir) == len - 1) dir = g_utf16_to_utf8 (wdir, -1, NULL, NULL, NULL); g_free (wdir); if (dir == NULL) dir = g_strdup ("\\"); return dir; #else const gchar *pwd; gchar *buffer = NULL; gchar *dir = NULL; static gulong max_len = 0; struct stat pwdbuf, dotbuf; pwd = g_getenv ("PWD"); if (pwd != NULL && g_stat (".", &dotbuf) == 0 && g_stat (pwd, &pwdbuf) == 0 && dotbuf.st_dev == pwdbuf.st_dev && dotbuf.st_ino == pwdbuf.st_ino) return g_strdup (pwd); if (max_len == 0) max_len = (G_PATH_LENGTH == -1) ? 2048 : G_PATH_LENGTH; while (max_len < G_MAXULONG / 2) { g_free (buffer); buffer = g_new (gchar, max_len + 1); *buffer = 0; dir = getcwd (buffer, max_len); if (dir || errno != ERANGE) break; max_len *= 2; } if (!dir || !*buffer) { /* hm, should we g_error() out here? * this can happen if e.g. "./" has mode \0000 */ buffer[0] = G_DIR_SEPARATOR; buffer[1] = 0; } dir = g_strdup (buffer); g_free (buffer); return dir; #endif /* !G_OS_WIN32 */ } #ifdef G_OS_WIN32 /* Binary compatibility versions. Not for newly compiled code. */ _GLIB_EXTERN gboolean g_file_test_utf8 (const gchar *filename, GFileTest test); _GLIB_EXTERN gboolean g_file_get_contents_utf8 (const gchar *filename, gchar **contents, gsize *length, GError **error); _GLIB_EXTERN gint g_mkstemp_utf8 (gchar *tmpl); _GLIB_EXTERN gint g_file_open_tmp_utf8 (const gchar *tmpl, gchar **name_used, GError **error); _GLIB_EXTERN gchar *g_get_current_dir_utf8 (void); gboolean g_file_test_utf8 (const gchar *filename, GFileTest test) { return g_file_test (filename, test); } gboolean g_file_get_contents_utf8 (const gchar *filename, gchar **contents, gsize *length, GError **error) { return g_file_get_contents (filename, contents, length, error); } gint g_mkstemp_utf8 (gchar *tmpl) { return g_mkstemp (tmpl); } gint g_file_open_tmp_utf8 (const gchar *tmpl, gchar **name_used, GError **error) { return g_file_open_tmp (tmpl, name_used, error); } gchar * g_get_current_dir_utf8 (void) { return g_get_current_dir (); } #endif