| /* GIO - GLib Input, Output and Streaming Library |
| * |
| * Copyright (C) 2006-2007 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 <http://www.gnu.org/licenses/>. |
| * |
| * Author: Alexander Larsson <alexl@redhat.com> |
| */ |
| |
| /* Needed for the statx() calls in inline functions in glocalfileinfo.h */ |
| #ifndef _GNU_SOURCE |
| #define _GNU_SOURCE |
| #endif |
| |
| #include "config.h" |
| |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <fcntl.h> |
| #include <errno.h> |
| #include <string.h> |
| |
| #include <glib.h> |
| #include <glib/gstdio.h> |
| #include "glibintl.h" |
| #include "gioerror.h" |
| #include "gcancellable.h" |
| #include "glocalfileoutputstream.h" |
| #include "gfileinfo.h" |
| #include "glocalfileinfo.h" |
| |
| #ifdef G_OS_UNIX |
| #include <unistd.h> |
| #include "gfiledescriptorbased.h" |
| #include <sys/uio.h> |
| #endif |
| |
| #include "glib-private.h" |
| #include "gioprivate.h" |
| |
| #ifdef G_OS_WIN32 |
| #include <io.h> |
| #ifndef S_ISDIR |
| #define S_ISDIR(m) (((m) & _S_IFMT) == _S_IFDIR) |
| #endif |
| #ifndef S_ISREG |
| #define S_ISREG(m) (((m) & _S_IFMT) == _S_IFREG) |
| #endif |
| #endif |
| |
| #ifndef O_BINARY |
| #define O_BINARY 0 |
| #endif |
| |
| #ifndef O_CLOEXEC |
| #define O_CLOEXEC 0 |
| #else |
| #define HAVE_O_CLOEXEC 1 |
| #endif |
| |
| struct _GLocalFileOutputStreamPrivate { |
| char *tmp_filename; |
| char *original_filename; |
| char *backup_filename; |
| char *etag; |
| guint sync_on_close : 1; |
| guint do_close : 1; |
| int fd; |
| }; |
| |
| #ifdef G_OS_UNIX |
| static void g_file_descriptor_based_iface_init (GFileDescriptorBasedIface *iface); |
| #endif |
| |
| #define g_local_file_output_stream_get_type _g_local_file_output_stream_get_type |
| #ifdef G_OS_UNIX |
| G_DEFINE_TYPE_WITH_CODE (GLocalFileOutputStream, g_local_file_output_stream, G_TYPE_FILE_OUTPUT_STREAM, |
| G_ADD_PRIVATE (GLocalFileOutputStream) |
| G_IMPLEMENT_INTERFACE (G_TYPE_FILE_DESCRIPTOR_BASED, |
| g_file_descriptor_based_iface_init)) |
| #else |
| G_DEFINE_TYPE_WITH_CODE (GLocalFileOutputStream, g_local_file_output_stream, G_TYPE_FILE_OUTPUT_STREAM, |
| G_ADD_PRIVATE (GLocalFileOutputStream)) |
| #endif |
| |
| |
| /* Some of the file replacement code was based on the code from gedit, |
| * relicenced to LGPL with permissions from the authors. |
| */ |
| |
| #define BACKUP_EXTENSION "~" |
| |
| static gssize g_local_file_output_stream_write (GOutputStream *stream, |
| const void *buffer, |
| gsize count, |
| GCancellable *cancellable, |
| GError **error); |
| #ifdef G_OS_UNIX |
| static gboolean g_local_file_output_stream_writev (GOutputStream *stream, |
| const GOutputVector *vectors, |
| gsize n_vectors, |
| gsize *bytes_written, |
| GCancellable *cancellable, |
| GError **error); |
| #endif |
| static gboolean g_local_file_output_stream_close (GOutputStream *stream, |
| GCancellable *cancellable, |
| GError **error); |
| static GFileInfo *g_local_file_output_stream_query_info (GFileOutputStream *stream, |
| const char *attributes, |
| GCancellable *cancellable, |
| GError **error); |
| static char * g_local_file_output_stream_get_etag (GFileOutputStream *stream); |
| static goffset g_local_file_output_stream_tell (GFileOutputStream *stream); |
| static gboolean g_local_file_output_stream_can_seek (GFileOutputStream *stream); |
| static gboolean g_local_file_output_stream_seek (GFileOutputStream *stream, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error); |
| static gboolean g_local_file_output_stream_can_truncate (GFileOutputStream *stream); |
| static gboolean g_local_file_output_stream_truncate (GFileOutputStream *stream, |
| goffset size, |
| GCancellable *cancellable, |
| GError **error); |
| #ifdef G_OS_UNIX |
| static int g_local_file_output_stream_get_fd (GFileDescriptorBased *stream); |
| #endif |
| |
| static void |
| g_local_file_output_stream_finalize (GObject *object) |
| { |
| GLocalFileOutputStream *file; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (object); |
| |
| g_free (file->priv->tmp_filename); |
| g_free (file->priv->original_filename); |
| g_free (file->priv->backup_filename); |
| g_free (file->priv->etag); |
| |
| G_OBJECT_CLASS (g_local_file_output_stream_parent_class)->finalize (object); |
| } |
| |
| static void |
| g_local_file_output_stream_class_init (GLocalFileOutputStreamClass *klass) |
| { |
| GObjectClass *gobject_class = G_OBJECT_CLASS (klass); |
| GOutputStreamClass *stream_class = G_OUTPUT_STREAM_CLASS (klass); |
| GFileOutputStreamClass *file_stream_class = G_FILE_OUTPUT_STREAM_CLASS (klass); |
| |
| gobject_class->finalize = g_local_file_output_stream_finalize; |
| |
| stream_class->write_fn = g_local_file_output_stream_write; |
| #ifdef G_OS_UNIX |
| stream_class->writev_fn = g_local_file_output_stream_writev; |
| #endif |
| stream_class->close_fn = g_local_file_output_stream_close; |
| file_stream_class->query_info = g_local_file_output_stream_query_info; |
| file_stream_class->get_etag = g_local_file_output_stream_get_etag; |
| file_stream_class->tell = g_local_file_output_stream_tell; |
| file_stream_class->can_seek = g_local_file_output_stream_can_seek; |
| file_stream_class->seek = g_local_file_output_stream_seek; |
| file_stream_class->can_truncate = g_local_file_output_stream_can_truncate; |
| file_stream_class->truncate_fn = g_local_file_output_stream_truncate; |
| } |
| |
| #ifdef G_OS_UNIX |
| static void |
| g_file_descriptor_based_iface_init (GFileDescriptorBasedIface *iface) |
| { |
| iface->get_fd = g_local_file_output_stream_get_fd; |
| } |
| #endif |
| |
| static void |
| g_local_file_output_stream_init (GLocalFileOutputStream *stream) |
| { |
| stream->priv = g_local_file_output_stream_get_instance_private (stream); |
| stream->priv->do_close = TRUE; |
| } |
| |
| static gssize |
| g_local_file_output_stream_write (GOutputStream *stream, |
| const void *buffer, |
| gsize count, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *file; |
| gssize res; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| while (1) |
| { |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return -1; |
| res = write (file->priv->fd, buffer, count); |
| if (res == -1) |
| { |
| int errsv = errno; |
| |
| if (errsv == EINTR) |
| continue; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error writing to file: %s"), |
| g_strerror (errsv)); |
| } |
| |
| break; |
| } |
| |
| return res; |
| } |
| |
| /* On Windows there is no equivalent API for files. The closest API to that is |
| * WriteFileGather() but it is useless in general: it requires, among other |
| * things, that each chunk is the size of a whole page and in memory aligned |
| * to a page. We can't possibly guarantee that in GLib. |
| */ |
| #ifdef G_OS_UNIX |
| /* Macro to check if struct iovec and GOutputVector have the same ABI */ |
| #define G_OUTPUT_VECTOR_IS_IOVEC (sizeof (struct iovec) == sizeof (GOutputVector) && \ |
| G_SIZEOF_MEMBER (struct iovec, iov_base) == G_SIZEOF_MEMBER (GOutputVector, buffer) && \ |
| G_STRUCT_OFFSET (struct iovec, iov_base) == G_STRUCT_OFFSET (GOutputVector, buffer) && \ |
| G_SIZEOF_MEMBER (struct iovec, iov_len) == G_SIZEOF_MEMBER (GOutputVector, size) && \ |
| G_STRUCT_OFFSET (struct iovec, iov_len) == G_STRUCT_OFFSET (GOutputVector, size)) |
| |
| static gboolean |
| g_local_file_output_stream_writev (GOutputStream *stream, |
| const GOutputVector *vectors, |
| gsize n_vectors, |
| gsize *bytes_written, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *file; |
| gssize res; |
| struct iovec *iov; |
| |
| if (bytes_written) |
| *bytes_written = 0; |
| |
| /* Clamp the number of vectors if more given than we can write in one go. |
| * The caller has to handle short writes anyway. |
| */ |
| if (n_vectors > G_IOV_MAX) |
| n_vectors = G_IOV_MAX; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| if (G_OUTPUT_VECTOR_IS_IOVEC) |
| { |
| /* ABI is compatible */ |
| iov = (struct iovec *) vectors; |
| } |
| else |
| { |
| gsize i; |
| |
| /* ABI is incompatible */ |
| iov = g_newa (struct iovec, n_vectors); |
| for (i = 0; i < n_vectors; i++) |
| { |
| iov[i].iov_base = (void *)vectors[i].buffer; |
| iov[i].iov_len = vectors[i].size; |
| } |
| } |
| |
| while (1) |
| { |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return FALSE; |
| res = writev (file->priv->fd, iov, n_vectors); |
| if (res == -1) |
| { |
| int errsv = errno; |
| |
| if (errsv == EINTR) |
| continue; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error writing to file: %s"), |
| g_strerror (errsv)); |
| } |
| else if (bytes_written) |
| { |
| *bytes_written = res; |
| } |
| |
| break; |
| } |
| |
| return res != -1; |
| } |
| #endif |
| |
| void |
| _g_local_file_output_stream_set_do_close (GLocalFileOutputStream *out, |
| gboolean do_close) |
| { |
| out->priv->do_close = do_close; |
| } |
| |
| gboolean |
| _g_local_file_output_stream_really_close (GLocalFileOutputStream *file, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileStat final_stat; |
| |
| if (file->priv->sync_on_close && |
| g_fsync (file->priv->fd) != 0) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error writing to file: %s"), |
| g_strerror (errsv)); |
| goto err_out; |
| } |
| |
| #ifdef G_OS_WIN32 |
| |
| /* Must close before renaming on Windows, so just do the close first |
| * in all cases for now. |
| */ |
| if (GLIB_PRIVATE_CALL (g_win32_fstat) (file->priv->fd, &final_stat) == 0) |
| file->priv->etag = _g_local_file_info_create_etag (&final_stat); |
| |
| if (!g_close (file->priv->fd, NULL)) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error closing file: %s"), |
| g_strerror (errsv)); |
| return FALSE; |
| } |
| |
| #endif |
| |
| if (file->priv->tmp_filename) |
| { |
| /* We need to move the temp file to its final place, |
| * and possibly create the backup file |
| */ |
| |
| if (file->priv->backup_filename) |
| { |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| goto err_out; |
| |
| #ifdef G_OS_UNIX |
| /* create original -> backup link, the original is then renamed over */ |
| if (g_unlink (file->priv->backup_filename) != 0 && |
| errno != ENOENT) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Error removing old backup link: %s"), |
| g_strerror (errsv)); |
| goto err_out; |
| } |
| |
| if (link (file->priv->original_filename, file->priv->backup_filename) != 0) |
| { |
| /* link failed or is not supported, try rename */ |
| if (g_rename (file->priv->original_filename, file->priv->backup_filename) != 0) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Error creating backup copy: %s"), |
| g_strerror (errsv)); |
| goto err_out; |
| } |
| } |
| #else |
| /* If link not supported, just rename... */ |
| if (g_rename (file->priv->original_filename, file->priv->backup_filename) != 0) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Error creating backup copy: %s"), |
| g_strerror (errsv)); |
| goto err_out; |
| } |
| #endif |
| } |
| |
| |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| goto err_out; |
| |
| /* tmp -> original */ |
| if (g_rename (file->priv->tmp_filename, file->priv->original_filename) != 0) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error renaming temporary file: %s"), |
| g_strerror (errsv)); |
| goto err_out; |
| } |
| |
| g_clear_pointer (&file->priv->tmp_filename, g_free); |
| } |
| |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| goto err_out; |
| |
| #ifndef G_OS_WIN32 /* Already did the fstat() and close() above on Win32 */ |
| |
| if (g_local_file_fstat (file->priv->fd, G_LOCAL_FILE_STAT_FIELD_MTIME, G_LOCAL_FILE_STAT_FIELD_ALL, &final_stat) == 0) |
| file->priv->etag = _g_local_file_info_create_etag (&final_stat); |
| |
| if (!g_close (file->priv->fd, NULL)) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error closing file: %s"), |
| g_strerror (errsv)); |
| goto err_out; |
| } |
| |
| #endif |
| |
| return TRUE; |
| err_out: |
| |
| #ifndef G_OS_WIN32 |
| /* A simple try to close the fd in case we fail before the actual close */ |
| g_close (file->priv->fd, NULL); |
| #endif |
| if (file->priv->tmp_filename) |
| g_unlink (file->priv->tmp_filename); |
| |
| return FALSE; |
| } |
| |
| |
| static gboolean |
| g_local_file_output_stream_close (GOutputStream *stream, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *file; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| if (file->priv->do_close) |
| return _g_local_file_output_stream_really_close (file, |
| cancellable, |
| error); |
| return TRUE; |
| } |
| |
| static char * |
| g_local_file_output_stream_get_etag (GFileOutputStream *stream) |
| { |
| GLocalFileOutputStream *file; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| return g_strdup (file->priv->etag); |
| } |
| |
| static goffset |
| g_local_file_output_stream_tell (GFileOutputStream *stream) |
| { |
| GLocalFileOutputStream *file; |
| off_t pos; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| pos = lseek (file->priv->fd, 0, SEEK_CUR); |
| |
| if (pos == (off_t)-1) |
| return 0; |
| |
| return pos; |
| } |
| |
| static gboolean |
| g_local_file_output_stream_can_seek (GFileOutputStream *stream) |
| { |
| GLocalFileOutputStream *file; |
| off_t pos; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| pos = lseek (file->priv->fd, 0, SEEK_CUR); |
| |
| if (pos == (off_t)-1 && errno == ESPIPE) |
| return FALSE; |
| |
| return TRUE; |
| } |
| |
| static int |
| seek_type_to_lseek (GSeekType type) |
| { |
| switch (type) |
| { |
| default: |
| case G_SEEK_CUR: |
| return SEEK_CUR; |
| |
| case G_SEEK_SET: |
| return SEEK_SET; |
| |
| case G_SEEK_END: |
| return SEEK_END; |
| } |
| } |
| |
| static gboolean |
| g_local_file_output_stream_seek (GFileOutputStream *stream, |
| goffset offset, |
| GSeekType type, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *file; |
| off_t pos; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| pos = lseek (file->priv->fd, offset, seek_type_to_lseek (type)); |
| |
| if (pos == (off_t)-1) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error seeking in file: %s"), |
| g_strerror (errsv)); |
| return FALSE; |
| } |
| |
| return TRUE; |
| } |
| |
| static gboolean |
| g_local_file_output_stream_can_truncate (GFileOutputStream *stream) |
| { |
| /* We can't truncate pipes and stuff where we can't seek */ |
| return g_local_file_output_stream_can_seek (stream); |
| } |
| |
| static gboolean |
| g_local_file_output_stream_truncate (GFileOutputStream *stream, |
| goffset size, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *file; |
| int res; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| restart: |
| #ifdef G_OS_WIN32 |
| res = g_win32_ftruncate (file->priv->fd, size); |
| #else |
| res = ftruncate (file->priv->fd, size); |
| #endif |
| |
| if (res == -1) |
| { |
| int errsv = errno; |
| |
| if (errsv == EINTR) |
| { |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return FALSE; |
| goto restart; |
| } |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error truncating file: %s"), |
| g_strerror (errsv)); |
| return FALSE; |
| } |
| |
| return TRUE; |
| } |
| |
| |
| static GFileInfo * |
| g_local_file_output_stream_query_info (GFileOutputStream *stream, |
| const char *attributes, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *file; |
| |
| file = G_LOCAL_FILE_OUTPUT_STREAM (stream); |
| |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return NULL; |
| |
| return _g_local_file_info_get_from_fd (file->priv->fd, |
| attributes, |
| error); |
| } |
| |
| GFileOutputStream * |
| _g_local_file_output_stream_new (int fd) |
| { |
| GLocalFileOutputStream *stream; |
| |
| stream = g_object_new (G_TYPE_LOCAL_FILE_OUTPUT_STREAM, NULL); |
| stream->priv->fd = fd; |
| return G_FILE_OUTPUT_STREAM (stream); |
| } |
| |
| static void |
| set_error_from_open_errno (const char *filename, |
| GError **error) |
| { |
| int errsv = errno; |
| |
| if (errsv == EINVAL) |
| /* This must be an invalid filename, on e.g. FAT */ |
| g_set_error_literal (error, G_IO_ERROR, |
| G_IO_ERROR_INVALID_FILENAME, |
| _("Invalid filename")); |
| else |
| { |
| char *display_name = g_filename_display_name (filename); |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error opening file “%s”: %s"), |
| display_name, g_strerror (errsv)); |
| g_free (display_name); |
| } |
| } |
| |
| static GFileOutputStream * |
| output_stream_open (const char *filename, |
| gint open_flags, |
| guint mode, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *stream; |
| gint fd; |
| |
| fd = g_open (filename, open_flags, mode); |
| if (fd == -1) |
| { |
| set_error_from_open_errno (filename, error); |
| return NULL; |
| } |
| |
| stream = g_object_new (G_TYPE_LOCAL_FILE_OUTPUT_STREAM, NULL); |
| stream->priv->fd = fd; |
| return G_FILE_OUTPUT_STREAM (stream); |
| } |
| |
| GFileOutputStream * |
| _g_local_file_output_stream_open (const char *filename, |
| gboolean readable, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| int open_flags; |
| |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return NULL; |
| |
| open_flags = O_BINARY; |
| if (readable) |
| open_flags |= O_RDWR; |
| else |
| open_flags |= O_WRONLY; |
| |
| return output_stream_open (filename, open_flags, 0666, cancellable, error); |
| } |
| |
| static gint |
| mode_from_flags_or_info (GFileCreateFlags flags, |
| GFileInfo *reference_info) |
| { |
| if (flags & G_FILE_CREATE_PRIVATE) |
| return 0600; |
| else if (reference_info && g_file_info_has_attribute (reference_info, "unix::mode")) |
| return g_file_info_get_attribute_uint32 (reference_info, "unix::mode") & (~S_IFMT); |
| else |
| return 0666; |
| } |
| |
| GFileOutputStream * |
| _g_local_file_output_stream_create (const char *filename, |
| gboolean readable, |
| GFileCreateFlags flags, |
| GFileInfo *reference_info, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| int mode; |
| int open_flags; |
| |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return NULL; |
| |
| mode = mode_from_flags_or_info (flags, reference_info); |
| |
| open_flags = O_CREAT | O_EXCL | O_BINARY; |
| if (readable) |
| open_flags |= O_RDWR; |
| else |
| open_flags |= O_WRONLY; |
| |
| return output_stream_open (filename, open_flags, mode, cancellable, error); |
| } |
| |
| GFileOutputStream * |
| _g_local_file_output_stream_append (const char *filename, |
| GFileCreateFlags flags, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| int mode; |
| |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return NULL; |
| |
| if (flags & G_FILE_CREATE_PRIVATE) |
| mode = 0600; |
| else |
| mode = 0666; |
| |
| return output_stream_open (filename, O_CREAT | O_APPEND | O_WRONLY | O_BINARY, mode, |
| cancellable, error); |
| } |
| |
| static char * |
| create_backup_filename (const char *filename) |
| { |
| return g_strconcat (filename, BACKUP_EXTENSION, NULL); |
| } |
| |
| #define BUFSIZE 8192 /* size of normal write buffer */ |
| |
| static gboolean |
| copy_file_data (gint sfd, |
| gint dfd, |
| GError **error) |
| { |
| gboolean ret = TRUE; |
| gpointer buffer; |
| const gchar *write_buffer; |
| gssize bytes_read; |
| gssize bytes_to_write; |
| gssize bytes_written; |
| |
| buffer = g_malloc (BUFSIZE); |
| |
| do |
| { |
| bytes_read = read (sfd, buffer, BUFSIZE); |
| if (bytes_read == -1) |
| { |
| int errsv = errno; |
| |
| if (errsv == EINTR) |
| continue; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error reading from file: %s"), |
| g_strerror (errsv)); |
| ret = FALSE; |
| break; |
| } |
| |
| bytes_to_write = bytes_read; |
| write_buffer = buffer; |
| |
| do |
| { |
| bytes_written = write (dfd, write_buffer, bytes_to_write); |
| if (bytes_written == -1) |
| { |
| int errsv = errno; |
| |
| if (errsv == EINTR) |
| continue; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error writing to file: %s"), |
| g_strerror (errsv)); |
| ret = FALSE; |
| break; |
| } |
| |
| bytes_to_write -= bytes_written; |
| write_buffer += bytes_written; |
| } |
| while (bytes_to_write > 0); |
| |
| } while ((bytes_read != 0) && (ret == TRUE)); |
| |
| g_free (buffer); |
| |
| return ret; |
| } |
| |
| static int |
| handle_overwrite_open (const char *filename, |
| gboolean readable, |
| const char *etag, |
| gboolean create_backup, |
| char **temp_filename, |
| GFileCreateFlags flags, |
| GFileInfo *reference_info, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| int fd = -1; |
| GLocalFileStat original_stat; |
| char *current_etag; |
| gboolean is_symlink; |
| int open_flags; |
| int res; |
| int mode; |
| int errsv; |
| gboolean replace_destination_set = (flags & G_FILE_CREATE_REPLACE_DESTINATION); |
| |
| mode = mode_from_flags_or_info (flags, reference_info); |
| |
| /* We only need read access to the original file if we are creating a backup. |
| * We also add O_CREAT to avoid a race if the file was just removed */ |
| if (create_backup || readable) |
| open_flags = O_RDWR | O_CREAT | O_BINARY; |
| else |
| open_flags = O_WRONLY | O_CREAT | O_BINARY; |
| |
| /* Some systems have O_NOFOLLOW, which lets us avoid some races |
| * when finding out if the file we opened was a symlink */ |
| #ifdef O_NOFOLLOW |
| is_symlink = FALSE; |
| fd = g_open (filename, open_flags | O_NOFOLLOW, mode); |
| errsv = errno; |
| #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__) |
| if (fd == -1 && errsv == EMLINK) |
| #elif defined(__NetBSD__) |
| if (fd == -1 && errsv == EFTYPE) |
| #else |
| if (fd == -1 && errsv == ELOOP) |
| #endif |
| { |
| /* Could be a symlink, or it could be a regular ELOOP error, |
| * but then the next open will fail too. */ |
| is_symlink = TRUE; |
| if (!replace_destination_set) |
| fd = g_open (filename, open_flags, mode); |
| } |
| #else /* if !O_NOFOLLOW */ |
| /* This is racy, but we do it as soon as possible to minimize the race */ |
| is_symlink = g_file_test (filename, G_FILE_TEST_IS_SYMLINK); |
| |
| if (!is_symlink || !replace_destination_set) |
| { |
| fd = g_open (filename, open_flags, mode); |
| errsv = errno; |
| } |
| #endif |
| |
| if (fd == -1 && |
| (!is_symlink || !replace_destination_set)) |
| { |
| char *display_name = g_filename_display_name (filename); |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error opening file “%s”: %s"), |
| display_name, g_strerror (errsv)); |
| g_free (display_name); |
| return -1; |
| } |
| |
| if (!is_symlink) |
| { |
| res = g_local_file_fstat (fd, |
| G_LOCAL_FILE_STAT_FIELD_TYPE | |
| G_LOCAL_FILE_STAT_FIELD_MODE | |
| G_LOCAL_FILE_STAT_FIELD_UID | |
| G_LOCAL_FILE_STAT_FIELD_GID | |
| G_LOCAL_FILE_STAT_FIELD_MTIME | |
| G_LOCAL_FILE_STAT_FIELD_NLINK, |
| G_LOCAL_FILE_STAT_FIELD_ALL, &original_stat); |
| errsv = errno; |
| } |
| else |
| { |
| res = g_local_file_lstat (filename, |
| G_LOCAL_FILE_STAT_FIELD_TYPE | |
| G_LOCAL_FILE_STAT_FIELD_MODE | |
| G_LOCAL_FILE_STAT_FIELD_UID | |
| G_LOCAL_FILE_STAT_FIELD_GID | |
| G_LOCAL_FILE_STAT_FIELD_MTIME | |
| G_LOCAL_FILE_STAT_FIELD_NLINK, |
| G_LOCAL_FILE_STAT_FIELD_ALL, &original_stat); |
| errsv = errno; |
| } |
| |
| if (res != 0) |
| { |
| char *display_name = g_filename_display_name (filename); |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error when getting information for file “%s”: %s"), |
| display_name, g_strerror (errsv)); |
| g_free (display_name); |
| goto error; |
| } |
| |
| /* not a regular file */ |
| if (!S_ISREG (_g_stat_mode (&original_stat))) |
| { |
| if (S_ISDIR (_g_stat_mode (&original_stat))) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_IS_DIRECTORY, |
| _("Target file is a directory")); |
| goto error; |
| } |
| else if (!is_symlink || |
| #ifdef S_ISLNK |
| !S_ISLNK (_g_stat_mode (&original_stat)) |
| #else |
| FALSE |
| #endif |
| ) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_NOT_REGULAR_FILE, |
| _("Target file is not a regular file")); |
| goto error; |
| } |
| } |
| |
| if (etag != NULL) |
| { |
| GLocalFileStat etag_stat; |
| GLocalFileStat *etag_stat_pointer; |
| |
| /* The ETag is calculated on the details of the target file, for symlinks, |
| * so we might need to stat() again. */ |
| if (is_symlink) |
| { |
| res = g_local_file_stat (filename, |
| G_LOCAL_FILE_STAT_FIELD_MTIME, |
| G_LOCAL_FILE_STAT_FIELD_ALL, &etag_stat); |
| errsv = errno; |
| |
| if (res != 0) |
| { |
| char *display_name = g_filename_display_name (filename); |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error when getting information for file “%s”: %s"), |
| display_name, g_strerror (errsv)); |
| g_free (display_name); |
| goto error; |
| } |
| |
| etag_stat_pointer = &etag_stat; |
| } |
| else |
| etag_stat_pointer = &original_stat; |
| |
| /* Compare the ETags */ |
| current_etag = _g_local_file_info_create_etag (etag_stat_pointer); |
| if (strcmp (etag, current_etag) != 0) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_WRONG_ETAG, |
| _("The file was externally modified")); |
| g_free (current_etag); |
| goto error; |
| } |
| g_free (current_etag); |
| } |
| |
| /* We use two backup strategies. |
| * The first one (which is faster) consist in saving to a |
| * tmp file then rename the original file to the backup and the |
| * tmp file to the original name. This is fast but doesn't work |
| * when the file is a link (hard or symbolic) or when we can't |
| * write to the current dir or can't set the permissions on the |
| * new file. |
| * The second strategy consist simply in copying the old file |
| * to a backup file and rewrite the contents of the file. |
| */ |
| |
| if (replace_destination_set || |
| (!(_g_stat_nlink (&original_stat) > 1) && !is_symlink)) |
| { |
| char *dirname, *tmp_filename; |
| int tmpfd; |
| |
| dirname = g_path_get_dirname (filename); |
| tmp_filename = g_build_filename (dirname, ".goutputstream-XXXXXX", NULL); |
| g_free (dirname); |
| |
| tmpfd = g_mkstemp_full (tmp_filename, (readable ? O_RDWR : O_WRONLY) | O_BINARY, mode); |
| if (tmpfd == -1) |
| { |
| g_free (tmp_filename); |
| goto fallback_strategy; |
| } |
| |
| /* try to keep permissions (unless replacing) */ |
| |
| if (!replace_destination_set && |
| ( |
| #ifdef HAVE_FCHOWN |
| fchown (tmpfd, _g_stat_uid (&original_stat), _g_stat_gid (&original_stat)) == -1 || |
| #endif |
| #ifdef HAVE_FCHMOD |
| fchmod (tmpfd, _g_stat_mode (&original_stat) & ~S_IFMT) == -1 || |
| #endif |
| 0 |
| ) |
| ) |
| { |
| GLocalFileStat tmp_statbuf; |
| int tres; |
| |
| tres = g_local_file_fstat (tmpfd, |
| G_LOCAL_FILE_STAT_FIELD_TYPE | |
| G_LOCAL_FILE_STAT_FIELD_MODE | |
| G_LOCAL_FILE_STAT_FIELD_UID | |
| G_LOCAL_FILE_STAT_FIELD_GID, |
| G_LOCAL_FILE_STAT_FIELD_ALL, &tmp_statbuf); |
| |
| /* Check that we really needed to change something */ |
| if (tres != 0 || |
| _g_stat_uid (&original_stat) != _g_stat_uid (&tmp_statbuf) || |
| _g_stat_gid (&original_stat) != _g_stat_gid (&tmp_statbuf) || |
| _g_stat_mode (&original_stat) != _g_stat_mode (&tmp_statbuf)) |
| { |
| g_close (tmpfd, NULL); |
| g_unlink (tmp_filename); |
| g_free (tmp_filename); |
| goto fallback_strategy; |
| } |
| } |
| |
| if (fd >= 0) |
| g_close (fd, NULL); |
| *temp_filename = tmp_filename; |
| return tmpfd; |
| } |
| |
| fallback_strategy: |
| |
| if (create_backup) |
| { |
| #if defined(HAVE_FCHOWN) && defined(HAVE_FCHMOD) |
| GLocalFileStat tmp_statbuf; |
| #endif |
| char *backup_filename; |
| int bfd; |
| |
| backup_filename = create_backup_filename (filename); |
| |
| if (g_unlink (backup_filename) == -1 && errno != ENOENT) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Backup file creation failed")); |
| g_free (backup_filename); |
| goto error; |
| } |
| |
| bfd = g_open (backup_filename, |
| O_WRONLY | O_CREAT | O_EXCL | O_BINARY, |
| _g_stat_mode (&original_stat) & 0777); |
| |
| if (bfd == -1) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Backup file creation failed")); |
| g_free (backup_filename); |
| goto error; |
| } |
| |
| /* If needed, Try to set the group of the backup same as the |
| * original file. If this fails, set the protection |
| * bits for the group same as the protection bits for |
| * others. */ |
| #if defined(HAVE_FCHOWN) && defined(HAVE_FCHMOD) |
| if (g_local_file_fstat (bfd, G_LOCAL_FILE_STAT_FIELD_GID, G_LOCAL_FILE_STAT_FIELD_ALL, &tmp_statbuf) != 0) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Backup file creation failed")); |
| g_unlink (backup_filename); |
| g_close (bfd, NULL); |
| g_free (backup_filename); |
| goto error; |
| } |
| |
| if ((_g_stat_gid (&original_stat) != _g_stat_gid (&tmp_statbuf)) && |
| fchown (bfd, (uid_t) -1, _g_stat_gid (&original_stat)) != 0) |
| { |
| if (fchmod (bfd, |
| (_g_stat_mode (&original_stat) & 0707) | |
| ((_g_stat_mode (&original_stat) & 07) << 3)) != 0) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Backup file creation failed")); |
| g_unlink (backup_filename); |
| g_close (bfd, NULL); |
| g_free (backup_filename); |
| goto error; |
| } |
| } |
| #endif |
| |
| if (!copy_file_data (fd, bfd, NULL)) |
| { |
| g_set_error_literal (error, |
| G_IO_ERROR, |
| G_IO_ERROR_CANT_CREATE_BACKUP, |
| _("Backup file creation failed")); |
| g_unlink (backup_filename); |
| g_close (bfd, NULL); |
| g_free (backup_filename); |
| |
| goto error; |
| } |
| |
| g_close (bfd, NULL); |
| g_free (backup_filename); |
| |
| /* Seek back to the start of the file after the backup copy */ |
| if (lseek (fd, 0, SEEK_SET) == -1) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error seeking in file: %s"), |
| g_strerror (errsv)); |
| goto error; |
| } |
| } |
| |
| if (replace_destination_set) |
| { |
| g_close (fd, NULL); |
| |
| if (g_unlink (filename) != 0) |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error removing old file: %s"), |
| g_strerror (errsv)); |
| goto error; |
| } |
| |
| if (readable) |
| open_flags = O_RDWR | O_CREAT | O_BINARY; |
| else |
| open_flags = O_WRONLY | O_CREAT | O_BINARY; |
| fd = g_open (filename, open_flags, mode); |
| if (fd == -1) |
| { |
| int errsv = errno; |
| char *display_name = g_filename_display_name (filename); |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error opening file “%s”: %s"), |
| display_name, g_strerror (errsv)); |
| g_free (display_name); |
| goto error; |
| } |
| } |
| else |
| { |
| /* Truncate the file at the start */ |
| #ifdef G_OS_WIN32 |
| if (g_win32_ftruncate (fd, 0) == -1) |
| #else |
| if (ftruncate (fd, 0) == -1) |
| #endif |
| { |
| int errsv = errno; |
| |
| g_set_error (error, G_IO_ERROR, |
| g_io_error_from_errno (errsv), |
| _("Error truncating file: %s"), |
| g_strerror (errsv)); |
| goto error; |
| } |
| } |
| |
| return fd; |
| |
| error: |
| if (fd >= 0) |
| g_close (fd, NULL); |
| |
| return -1; |
| } |
| |
| GFileOutputStream * |
| _g_local_file_output_stream_replace (const char *filename, |
| gboolean readable, |
| const char *etag, |
| gboolean create_backup, |
| GFileCreateFlags flags, |
| GFileInfo *reference_info, |
| GCancellable *cancellable, |
| GError **error) |
| { |
| GLocalFileOutputStream *stream; |
| int mode; |
| int fd; |
| char *temp_file; |
| gboolean sync_on_close; |
| int open_flags; |
| |
| if (g_cancellable_set_error_if_cancelled (cancellable, error)) |
| return NULL; |
| |
| temp_file = NULL; |
| |
| mode = mode_from_flags_or_info (flags, reference_info); |
| sync_on_close = FALSE; |
| |
| /* If the file doesn't exist, create it */ |
| open_flags = O_CREAT | O_EXCL | O_BINARY | O_CLOEXEC; |
| if (readable) |
| open_flags |= O_RDWR; |
| else |
| open_flags |= O_WRONLY; |
| fd = g_open (filename, open_flags, mode); |
| |
| if (fd == -1 && errno == EEXIST) |
| { |
| /* The file already exists */ |
| fd = handle_overwrite_open (filename, readable, etag, |
| create_backup, &temp_file, |
| flags, reference_info, |
| cancellable, error); |
| if (fd == -1) |
| return NULL; |
| |
| /* 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.) |
| */ |
| sync_on_close = TRUE; |
| } |
| else if (fd == -1) |
| { |
| set_error_from_open_errno (filename, error); |
| return NULL; |
| } |
| #if !defined(HAVE_O_CLOEXEC) && defined(F_SETFD) |
| else |
| fcntl (fd, F_SETFD, FD_CLOEXEC); |
| #endif |
| |
| stream = g_object_new (G_TYPE_LOCAL_FILE_OUTPUT_STREAM, NULL); |
| stream->priv->fd = fd; |
| stream->priv->sync_on_close = sync_on_close; |
| stream->priv->tmp_filename = temp_file; |
| if (create_backup) |
| stream->priv->backup_filename = create_backup_filename (filename); |
| stream->priv->original_filename = g_strdup (filename); |
| |
| return G_FILE_OUTPUT_STREAM (stream); |
| } |
| |
| gint |
| _g_local_file_output_stream_get_fd (GLocalFileOutputStream *stream) |
| { |
| g_return_val_if_fail (G_IS_LOCAL_FILE_OUTPUT_STREAM (stream), -1); |
| return stream->priv->fd; |
| } |
| |
| #ifdef G_OS_UNIX |
| static int |
| g_local_file_output_stream_get_fd (GFileDescriptorBased *fd_based) |
| { |
| GLocalFileOutputStream *stream = G_LOCAL_FILE_OUTPUT_STREAM (fd_based); |
| return _g_local_file_output_stream_get_fd (stream); |
| } |
| #endif |
