glib/glib/gfileutils.c
Alexander Larsson 6cff88ba18 Bug 575555 – Use fsync() when replacing files to avoid data loss on
2009-03-16  Alexander Larsson  <alexl@redhat.com>

	Bug 575555 – Use fsync() when replacing files to avoid data loss on crash

        * configure.in:
	Look for fsync().

        * glib/gfileutils.c:
        (write_to_temp_file):
	fsync temp file if destination file exists

2009-03-16  Alexander Larsson  <alexl@redhat.com>

	Bug 575555 – Use fsync() when replacing files to avoid data loss on crash

        * glocalfileoutputstream.c:
        (g_local_file_output_stream_close):
        (_g_local_file_output_stream_replace):
	fsync temp file before closing if replacing target file

	

svn path=/trunk/; revision=7991
2009-03-16 16:03:13 +00:00

1966 lines
46 KiB
C

/* gfileutils.c - File utility functions
*
* Copyright 2000 Red Hat, Inc.
*
* GLib 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 of the
* License, or (at your option) any later version.
*
* GLib 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 GLib; see the file COPYING.LIB. If not,
* write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include "config.h"
#include "glib.h"
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#ifdef G_OS_WIN32
#include <windows.h>
#include <io.h>
#endif /* G_OS_WIN32 */
#ifndef S_ISLNK
#define S_ISLNK(x) 0
#endif
#ifndef O_BINARY
#define O_BINARY 0
#endif
#include "gstdio.h"
#include "glibintl.h"
#include "galias.h"
static gint create_temp_file (gchar *tmpl,
int permissions);
/**
* g_mkdir_with_parents:
* @pathname: 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)
{
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: 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, <literal>(G_FILE_TEST_EXISTS |
* G_FILE_TEST_IS_DIR)</literal> 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!
* |[
* /&ast; DON'T DO THIS &ast;/
* if (!g_file_test (filename, G_FILE_TEST_IS_SYMLINK))
* {
* fd = g_open (filename, O_WRONLY);
* /&ast; write to fd &ast;/
* }
* ]|
*
* 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.
*
* Return value: whether a test was %TRUE
**/
gboolean
g_file_test (const gchar *filename,
GFileTest test)
{
#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
int attributes;
wchar_t *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)
return (attributes & (FILE_ATTRIBUTE_DIRECTORY | FILE_ATTRIBUTE_DEVICE)) == 0;
if (test & G_FILE_TEST_IS_DIR)
return (attributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
if (test & G_FILE_TEST_IS_EXECUTABLE)
{
const gchar *lastdot = strrchr (filename, '.');
const gchar *pathext = NULL, *p;
int extlen;
if (lastdot == NULL)
return FALSE;
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)
return FALSE;
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);
return FALSE;
}
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
}
GQuark
g_file_error_quark (void)
{
return g_quark_from_static_string ("g-file-error-quark");
}
/**
* g_file_error_from_errno:
* @err_no: an "errno" value
*
* Gets a #GFileError constant based on the passed-in @errno.
* 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.
*
* Return value: #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;
break;
#endif
#ifdef EISDIR
case EISDIR:
return G_FILE_ERROR_ISDIR;
break;
#endif
#ifdef EACCES
case EACCES:
return G_FILE_ERROR_ACCES;
break;
#endif
#ifdef ENAMETOOLONG
case ENAMETOOLONG:
return G_FILE_ERROR_NAMETOOLONG;
break;
#endif
#ifdef ENOENT
case ENOENT:
return G_FILE_ERROR_NOENT;
break;
#endif
#ifdef ENOTDIR
case ENOTDIR:
return G_FILE_ERROR_NOTDIR;
break;
#endif
#ifdef ENXIO
case ENXIO:
return G_FILE_ERROR_NXIO;
break;
#endif
#ifdef ENODEV
case ENODEV:
return G_FILE_ERROR_NODEV;
break;
#endif
#ifdef EROFS
case EROFS:
return G_FILE_ERROR_ROFS;
break;
#endif
#ifdef ETXTBSY
case ETXTBSY:
return G_FILE_ERROR_TXTBSY;
break;
#endif
#ifdef EFAULT
case EFAULT:
return G_FILE_ERROR_FAULT;
break;
#endif
#ifdef ELOOP
case ELOOP:
return G_FILE_ERROR_LOOP;
break;
#endif
#ifdef ENOSPC
case ENOSPC:
return G_FILE_ERROR_NOSPC;
break;
#endif
#ifdef ENOMEM
case ENOMEM:
return G_FILE_ERROR_NOMEM;
break;
#endif
#ifdef EMFILE
case EMFILE:
return G_FILE_ERROR_MFILE;
break;
#endif
#ifdef ENFILE
case ENFILE:
return G_FILE_ERROR_NFILE;
break;
#endif
#ifdef EBADF
case EBADF:
return G_FILE_ERROR_BADF;
break;
#endif
#ifdef EINVAL
case EINVAL:
return G_FILE_ERROR_INVAL;
break;
#endif
#ifdef EPIPE
case EPIPE:
return G_FILE_ERROR_PIPE;
break;
#endif
#ifdef EAGAIN
case EAGAIN:
return G_FILE_ERROR_AGAIN;
break;
#endif
#ifdef EINTR
case EINTR:
return G_FILE_ERROR_INTR;
break;
#endif
#ifdef EIO
case EIO:
return G_FILE_ERROR_IO;
break;
#endif
#ifdef EPERM
case EPERM:
return G_FILE_ERROR_PERM;
break;
#endif
#ifdef ENOSYS
case ENOSYS:
return G_FILE_ERROR_NOSYS;
break;
#endif
default:
return G_FILE_ERROR_FAILED;
break;
}
}
static gboolean
get_contents_stdio (const gchar *display_filename,
FILE *f,
gchar **contents,
gsize *length,
GError **error)
{
gchar buf[4096];
gsize bytes;
gchar *str = NULL;
gsize total_bytes = 0;
gsize total_allocated = 0;
gchar *tmp;
g_assert (f != NULL);
while (!feof (f))
{
gint save_errno;
bytes = fread (buf, 1, sizeof (buf), f);
save_errno = errno;
while ((total_bytes + bytes + 1) > total_allocated)
{
if (str)
total_allocated *= 2;
else
total_allocated = MIN (bytes + 1, sizeof (buf));
tmp = g_try_realloc (str, total_allocated);
if (tmp == NULL)
{
g_set_error (error,
G_FILE_ERROR,
G_FILE_ERROR_NOMEM,
_("Could not allocate %lu bytes to read file \"%s\""),
(gulong) total_allocated,
display_filename);
goto error;
}
str = tmp;
}
if (ferror (f))
{
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));
goto error;
}
memcpy (str + total_bytes, buf, bytes);
if (total_bytes + bytes < total_bytes)
{
g_set_error (error,
G_FILE_ERROR,
G_FILE_ERROR_FAILED,
_("File \"%s\" is too large"),
display_filename);
goto error;
}
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;
error:
g_free (str);
fclose (f);
return FALSE;
}
#ifndef G_OS_WIN32
static gboolean
get_contents_regfile (const gchar *display_filename,
struct stat *stat_buf,
gint fd,
gchar **contents,
gsize *length,
GError **error)
{
gchar *buf;
gsize bytes_read;
gsize size;
gsize alloc_size;
size = stat_buf->st_size;
alloc_size = size + 1;
buf = g_try_malloc (alloc_size);
if (buf == NULL)
{
g_set_error (error,
G_FILE_ERROR,
G_FILE_ERROR_NOMEM,
_("Could not allocate %lu bytes to read file \"%s\""),
(gulong) alloc_size,
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);
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));
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;
gchar *display_filename = g_filename_display_name (filename);
/* O_BINARY useful on Cygwin */
fd = open (filename, O_RDONLY|O_BINARY);
if (fd < 0)
{
int save_errno = errno;
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to open file '%s': %s"),
display_filename,
g_strerror (save_errno));
g_free (display_filename);
return FALSE;
}
/* I don't think this will ever fail, aside from ENOMEM, but. */
if (fstat (fd, &stat_buf) < 0)
{
int save_errno = errno;
close (fd);
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to get attributes of file '%s': fstat() failed: %s"),
display_filename,
g_strerror (save_errno));
g_free (display_filename);
return FALSE;
}
if (stat_buf.st_size > 0 && S_ISREG (stat_buf.st_mode))
{
gboolean retval = get_contents_regfile (display_filename,
&stat_buf,
fd,
contents,
length,
error);
g_free (display_filename);
return retval;
}
else
{
FILE *f;
gboolean retval;
f = fdopen (fd, "r");
if (f == NULL)
{
int save_errno = errno;
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to open file '%s': fdopen() failed: %s"),
display_filename,
g_strerror (save_errno));
g_free (display_filename);
return FALSE;
}
retval = get_contents_stdio (display_filename, f, contents, length, error);
g_free (display_filename);
return retval;
}
}
#else /* G_OS_WIN32 */
static gboolean
get_contents_win32 (const gchar *filename,
gchar **contents,
gsize *length,
GError **error)
{
FILE *f;
gboolean retval;
gchar *display_filename = g_filename_display_name (filename);
int save_errno;
f = g_fopen (filename, "rb");
save_errno = errno;
if (f == NULL)
{
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to open file '%s': %s"),
display_filename,
g_strerror (save_errno));
g_free (display_filename);
return FALSE;
}
retval = get_contents_stdio (display_filename, f, contents, length, error);
g_free (display_filename);
return retval;
}
#endif
/**
* g_file_get_contents:
* @filename: name of a file to read contents from, in the GLib file name encoding
* @contents: location to store an allocated string, use g_free() to free
* the returned string
* @length: 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.
*
* Return value: %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 *display_name;
gchar *retval;
FILE *file;
gint fd;
int save_errno;
retval = NULL;
tmp_name = g_strdup_printf ("%s.XXXXXX", dest_file);
errno = 0;
fd = create_temp_file (tmp_name, 0666);
save_errno = errno;
display_name = g_filename_display_name (tmp_name);
if (fd == -1)
{
g_set_error (err,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to create file '%s': %s"),
display_name, g_strerror (save_errno));
goto out;
}
errno = 0;
file = fdopen (fd, "wb");
if (!file)
{
save_errno = errno;
g_set_error (err,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to open file '%s' for writing: fdopen() failed: %s"),
display_name,
g_strerror (save_errno));
close (fd);
g_unlink (tmp_name);
goto out;
}
if (length > 0)
{
gsize n_written;
errno = 0;
n_written = fwrite (contents, 1, length, file);
if (n_written < length)
{
save_errno = errno;
g_set_error (err,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to write file '%s': fwrite() failed: %s"),
display_name,
g_strerror (save_errno));
fclose (file);
g_unlink (tmp_name);
goto out;
}
}
errno = 0;
if (fflush (file) != 0)
{
save_errno = errno;
g_set_error (err,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to write file '%s': fflush() failed: %s"),
display_name,
g_strerror (save_errno));
g_unlink (tmp_name);
goto out;
}
#ifdef HAVE_FSYNC
errno = 0;
/* If the final destination exists, 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_file_test (dest_file, G_FILE_TEST_EXISTS) &&
fsync (fileno (file)) != 0)
{
save_errno = errno;
g_set_error (err,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to write file '%s': fsync() failed: %s"),
display_name,
g_strerror (save_errno));
g_unlink (tmp_name);
goto out;
}
#endif
errno = 0;
if (fclose (file) == EOF)
{
save_errno = errno;
g_set_error (err,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to close file '%s': fclose() failed: %s"),
display_name,
g_strerror (save_errno));
g_unlink (tmp_name);
goto out;
}
retval = g_strdup (tmp_name);
out:
g_free (tmp_name);
g_free (display_name);
return retval;
}
/**
* g_file_set_contents:
* @filename: name of a file to write @contents to, in the GLib file name
* encoding
* @contents: 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:
* <itemizedlist>
* <listitem>
* 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.
* </listitem>
* <listitem>
* 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.
* </listitem>
* <listitem>
* 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.
* </listitem>
* </itemizedlist>
*
* If the call was sucessful, 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.
*
* Return value: %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)
{
gchar *display_filename = g_filename_display_name (filename);
int save_errno = errno;
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Existing file '%s' could not be removed: g_unlink() failed: %s"),
display_filename,
g_strerror (save_errno));
g_free (display_filename);
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;
}
/*
* create_temp_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.
*/
static gint
create_temp_file (gchar *tmpl,
int permissions)
{
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;
/* 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];
/* tmpl is in UTF-8 on Windows, thus use g_open() */
fd = g_open (tmpl, O_RDWR | O_CREAT | O_EXCL | O_BINARY, permissions);
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;
}
/**
* g_mkstemp:
* @tmpl: 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.
*
* Return value: 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.
*/
gint
g_mkstemp (gchar *tmpl)
{
return create_temp_file (tmpl, 0600);
}
/**
* g_file_open_tmp:
* @tmpl: Template for file name, as in g_mkstemp(), basename only,
* or %NULL, to a default template
* @name_used: 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.
*
* The actual name used is returned in @name_used if non-%NULL. This
* string should be freed with g_free() when not needed any longer.
* The returned name is in the GLib file name encoding.
*
* Return value: 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)
{
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 = g_mkstemp (fulltemplate);
if (retval == -1)
{
int save_errno = errno;
gchar *display_fulltemplate = g_filename_display_name (fulltemplate);
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to create file '%s': %s"),
display_fulltemplate, g_strerror (save_errno));
g_free (display_fulltemplate);
g_free (fulltemplate);
return -1;
}
if (name_used)
*name_used = fulltemplate;
else
g_free (fulltemplate);
return retval;
}
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 (start &&
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: %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.
*
* Return value: 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: a string used to separator the elements of the path.
* @first_element: the first element in the path
* @Varargs: 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 <literal>ABA</literal>, <literal>ABABA</literal>
* 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.
*
* Return value: 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, &current_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: %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.
*
* Return value: 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: the first element in the path
* @Varargs: 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 <literal>g_build_path
* (G_DIR_SEPARATOR_S, first_element, ....)</literal>.
*
* On Windows, it takes into account that either the backslash
* (<literal>\</literal> or slash (<literal>/</literal>) 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.
*
* Return value: 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;
}
#define KILOBYTE_FACTOR 1024.0
#define MEGABYTE_FACTOR (1024.0 * 1024.0)
#define GIGABYTE_FACTOR (1024.0 * 1024.0 * 1024.0)
/**
* g_format_size_for_display:
* @size: a size in bytes.
*
* Formats a size (for example the size of a file) into a human readable string.
* Sizes are rounded to the nearest size prefix (KB, MB, GB) and are displayed
* rounded to the nearest tenth. E.g. the file size 3292528 bytes will be
* converted into the string "3.1 MB".
*
* The prefix units base is 1024 (i.e. 1 KB is 1024 bytes).
*
* This string should be freed with g_free() when not needed any longer.
*
* Returns: a newly-allocated formatted string containing a human readable
* file size.
*
* Since: 2.16
**/
char *
g_format_size_for_display (goffset size)
{
if (size < (goffset) KILOBYTE_FACTOR)
return g_strdup_printf (g_dngettext(GETTEXT_PACKAGE, "%u byte", "%u bytes",(guint) size), (guint) size);
else
{
gdouble displayed_size;
if (size < (goffset) MEGABYTE_FACTOR)
{
displayed_size = (gdouble) size / KILOBYTE_FACTOR;
return g_strdup_printf (_("%.1f KB"), displayed_size);
}
else if (size < (goffset) GIGABYTE_FACTOR)
{
displayed_size = (gdouble) size / MEGABYTE_FACTOR;
return g_strdup_printf (_("%.1f MB"), displayed_size);
}
else
{
displayed_size = (gdouble) size / GIGABYTE_FACTOR;
return g_strdup_printf (_("%.1f GB"), displayed_size);
}
}
}
/**
* g_file_read_link:
* @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: 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)
{
#ifdef HAVE_READLINK
gchar *buffer;
guint size;
gint read_size;
size = 256;
buffer = g_malloc (size);
while (TRUE)
{
read_size = readlink (filename, buffer, size);
if (read_size < 0) {
int save_errno = errno;
gchar *display_filename = g_filename_display_name (filename);
g_free (buffer);
g_set_error (error,
G_FILE_ERROR,
g_file_error_from_errno (save_errno),
_("Failed to read the symbolic link '%s': %s"),
display_filename,
g_strerror (save_errno));
g_free (display_filename);
return NULL;
}
if (read_size < size)
{
buffer[read_size] = 0;
return buffer;
}
size *= 2;
buffer = g_realloc (buffer, size);
}
#else
g_set_error_literal (error,
G_FILE_ERROR,
G_FILE_ERROR_INVAL,
_("Symbolic links not supported"));
return NULL;
#endif
}
/* NOTE : Keep this part last to ensure nothing in this file uses the
* below binary compatibility versions.
*/
#if defined (G_OS_WIN32) && !defined (_WIN64)
/* Binary compatibility versions. Will be called by code compiled
* against quite old (pre-2.8, I think) headers only, not from more
* recently compiled code.
*/
#undef g_file_test
gboolean
g_file_test (const gchar *filename,
GFileTest test)
{
gchar *utf8_filename = g_locale_to_utf8 (filename, -1, NULL, NULL, NULL);
gboolean retval;
if (utf8_filename == NULL)
return FALSE;
retval = g_file_test_utf8 (utf8_filename, test);
g_free (utf8_filename);
return retval;
}
#undef g_file_get_contents
gboolean
g_file_get_contents (const gchar *filename,
gchar **contents,
gsize *length,
GError **error)
{
gchar *utf8_filename = g_locale_to_utf8 (filename, -1, NULL, NULL, error);
gboolean retval;
if (utf8_filename == NULL)
return FALSE;
retval = g_file_get_contents_utf8 (utf8_filename, contents, length, error);
g_free (utf8_filename);
return retval;
}
#undef g_mkstemp
gint
g_mkstemp (gchar *tmpl)
{
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;
/* find the last occurrence of 'XXXXXX' */
XXXXXX = g_strrstr (tmpl, "XXXXXX");
if (!XXXXXX)
{
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];
/* This is the backward compatibility system codepage version,
* thus use normal open().
*/
fd = open (tmpl, O_RDWR | O_CREAT | O_EXCL | O_BINARY, 0600);
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;
}
#undef g_file_open_tmp
gint
g_file_open_tmp (const gchar *tmpl,
gchar **name_used,
GError **error)
{
gchar *utf8_tmpl = g_locale_to_utf8 (tmpl, -1, NULL, NULL, error);
gchar *utf8_name_used;
gint retval;
if (utf8_tmpl == NULL)
return -1;
retval = g_file_open_tmp_utf8 (utf8_tmpl, &utf8_name_used, error);
if (retval == -1)
return -1;
if (name_used)
*name_used = g_locale_from_utf8 (utf8_name_used, -1, NULL, NULL, NULL);
g_free (utf8_name_used);
return retval;
}
#endif
#define __G_FILEUTILS_C__
#include "galiasdef.c"