X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=glib%2Fgmappedfile.c;h=7c8702d2f59ea09c96b067d5be35c0f4201900c2;hb=20f6cc2a10ba26860e7a6d27c100deadb5497772;hp=d3d4de8bc2b2a309f0e6c7a97dca7d27408652e1;hpb=d87c91a396179516c8ba900dc402dfcb7063af83;p=platform%2Fupstream%2Fglib.git diff --git a/glib/gmappedfile.c b/glib/gmappedfile.c index d3d4de8..7c8702d 100644 --- a/glib/gmappedfile.c +++ b/glib/gmappedfile.c @@ -14,9 +14,7 @@ * 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, write to the - * Free Software Foundation, Inc., 59 Temple Place - Suite 330, - * Boston, MA 02111-1307, USA. + * License along with this library; if not, see . */ #include "config.h" @@ -25,18 +23,29 @@ #include #include #include -#ifdef HAVE_UNISTD_H -#include -#endif #ifdef HAVE_MMAP #include #endif #include "glibconfig.h" +#ifdef G_OS_UNIX +#include +#endif + #ifdef G_OS_WIN32 #include #include + +#undef fstat +#define fstat(a,b) _fstati64(a,b) +#undef stat +#define stat _stati64 + +#ifndef S_ISREG +#define S_ISREG(m) (((m) & _S_IFMT) == _S_IFREG) +#endif + #endif #include "gconvert.h" @@ -47,10 +56,10 @@ #include "gmessages.h" #include "gstdio.h" #include "gstrfuncs.h" +#include "gatomic.h" #include "glibintl.h" -#include "galias.h" #ifndef _O_BINARY #define _O_BINARY 0 @@ -60,88 +69,81 @@ #define MAP_FAILED ((void *) -1) #endif -struct _GMappedFile +/** + * GMappedFile: + * + * The #GMappedFile represents a file mapping created with + * g_mapped_file_new(). It has only private members and should + * not be accessed directly. + */ + +struct _GMappedFile { - gsize length; gchar *contents; + gsize length; + gpointer free_func; + int ref_count; #ifdef G_OS_WIN32 HANDLE mapping; #endif }; -/** - * g_mapped_file_new: - * @filename: The path of the file to load, in the GLib filename encoding - * @writable: wether the mapping should be writable - * @error: return location for a #GError, or %NULL - * - * Maps a file into memory. On UNIX, this is using the mmap() function. - * - * If @writable is %TRUE, the mapped buffer may be modified, otherwise - * it is an error to modify the mapped buffer. Modifications to the buffer - * are not visible to other processes mapping the same file, and are not - * written back to the file. - * - * Note that modifications of the underlying file might affect the contents - * of the #GMappedFile. Therefore, mapping should only be used if the file - * will not be modified, or if all modifications of the file are done - * atomically (e.g. using g_file_set_contents()). - * - * Return value: a newly allocated #GMappedFile which must be freed - * with g_mapped_file_free(), or %NULL if the mapping failed. - * - * Since: 2.8 - */ -GMappedFile * -g_mapped_file_new (const gchar *filename, - gboolean writable, - GError **error) +static void +g_mapped_file_destroy (GMappedFile *file) { - GMappedFile *file; - int fd; - struct stat st; - - g_return_val_if_fail (filename != NULL, NULL); - g_return_val_if_fail (!error || *error == NULL, NULL); - - fd = g_open (filename, (writable ? O_RDWR : O_RDONLY) | _O_BINARY, 0); - if (fd == -1) + if (file->length) { - int save_errno = errno; - gchar *display_filename = g_filename_display_name (filename); - - g_set_error (error, - G_FILE_ERROR, - g_file_error_from_errno (save_errno), - _("Failed to open file '%s': open() failed: %s"), - display_filename, - g_strerror (save_errno)); - g_free (display_filename); - return NULL; +#ifdef HAVE_MMAP + munmap (file->contents, file->length); +#endif +#ifdef G_OS_WIN32 + UnmapViewOfFile (file->contents); + CloseHandle (file->mapping); +#endif } - file = g_new0 (GMappedFile, 1); + g_slice_free (GMappedFile, file); +} + +static GMappedFile* +mapped_file_new_from_fd (int fd, + gboolean writable, + const gchar *filename, + GError **error) +{ + GMappedFile *file; + struct stat st; + + file = g_slice_new0 (GMappedFile); + file->ref_count = 1; + file->free_func = g_mapped_file_destroy; if (fstat (fd, &st) == -1) { int save_errno = errno; - gchar *display_filename = g_filename_display_name (filename); + gchar *display_filename = filename ? g_filename_display_name (filename) : NULL; 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, + _("Failed to get attributes of file '%s%s%s%s': fstat() failed: %s"), + display_filename ? display_filename : "fd", + display_filename ? "' " : "", + display_filename ? display_filename : "", + display_filename ? "'" : "", g_strerror (save_errno)); g_free (display_filename); goto out; } - if (st.st_size == 0) + /* mmap() on size 0 will fail with EINVAL, so we avoid calling mmap() + * in that case -- but only if we have a regular file; we still want + * attempts to mmap a character device to fail, for example. + */ + if (st.st_size == 0 && S_ISREG (st.st_mode)) { file->length = 0; - file->contents = ""; - close (fd); + file->contents = NULL; return file; } @@ -185,29 +187,124 @@ g_mapped_file_new (const gchar *filename, if (file->contents == MAP_FAILED) { int save_errno = errno; - gchar *display_filename = g_filename_display_name (filename); - + gchar *display_filename = filename ? g_filename_display_name (filename) : NULL; + g_set_error (error, G_FILE_ERROR, g_file_error_from_errno (save_errno), - _("Failed to map file '%s': mmap() failed: %s"), - display_filename, + _("Failed to map %s%s%s%s: mmap() failed: %s"), + display_filename ? display_filename : "fd", + display_filename ? "' " : "", + display_filename ? display_filename : "", + display_filename ? "'" : "", g_strerror (save_errno)); g_free (display_filename); goto out; } - close (fd); return file; out: - close (fd); - g_free (file); + g_slice_free (GMappedFile, file); return NULL; } /** + * g_mapped_file_new: + * @filename: The path of the file to load, in the GLib filename encoding + * @writable: whether the mapping should be writable + * @error: return location for a #GError, or %NULL + * + * Maps a file into memory. On UNIX, this is using the mmap() function. + * + * If @writable is %TRUE, the mapped buffer may be modified, otherwise + * it is an error to modify the mapped buffer. Modifications to the buffer + * are not visible to other processes mapping the same file, and are not + * written back to the file. + * + * Note that modifications of the underlying file might affect the contents + * of the #GMappedFile. Therefore, mapping should only be used if the file + * will not be modified, or if all modifications of the file are done + * atomically (e.g. using g_file_set_contents()). + * + * If @filename is the name of an empty, regular file, the function + * will successfully return an empty #GMappedFile. In other cases of + * size 0 (e.g. device files such as /dev/null), @error will be set + * to the #GFileError value #G_FILE_ERROR_INVAL. + * + * Returns: a newly allocated #GMappedFile which must be unref'd + * with g_mapped_file_unref(), or %NULL if the mapping failed. + * + * Since: 2.8 + */ +GMappedFile * +g_mapped_file_new (const gchar *filename, + gboolean writable, + GError **error) +{ + GMappedFile *file; + int fd; + + g_return_val_if_fail (filename != NULL, NULL); + g_return_val_if_fail (!error || *error == NULL, NULL); + + fd = g_open (filename, (writable ? O_RDWR : O_RDONLY) | _O_BINARY, 0); + if (fd == -1) + { + int save_errno = errno; + gchar *display_filename = g_filename_display_name (filename); + + g_set_error (error, + G_FILE_ERROR, + g_file_error_from_errno (save_errno), + _("Failed to open file '%s': open() failed: %s"), + display_filename, + g_strerror (save_errno)); + g_free (display_filename); + return NULL; + } + + file = mapped_file_new_from_fd (fd, writable, filename, error); + + close (fd); + + return file; +} + + +/** + * g_mapped_file_new_from_fd: + * @fd: The file descriptor of the file to load + * @writable: whether the mapping should be writable + * @error: return location for a #GError, or %NULL + * + * Maps a file into memory. On UNIX, this is using the mmap() function. + * + * If @writable is %TRUE, the mapped buffer may be modified, otherwise + * it is an error to modify the mapped buffer. Modifications to the buffer + * are not visible to other processes mapping the same file, and are not + * written back to the file. + * + * Note that modifications of the underlying file might affect the contents + * of the #GMappedFile. Therefore, mapping should only be used if the file + * will not be modified, or if all modifications of the file are done + * atomically (e.g. using g_file_set_contents()). + * + * Returns: a newly allocated #GMappedFile which must be unref'd + * with g_mapped_file_unref(), or %NULL if the mapping failed. + * + * Since: 2.32 + */ +GMappedFile * +g_mapped_file_new_from_fd (gint fd, + gboolean writable, + GError **error) +{ + return mapped_file_new_from_fd (fd, writable, NULL, error); +} + +/** * g_mapped_file_get_length: * @file: a #GMappedFile * @@ -234,7 +331,9 @@ g_mapped_file_get_length (GMappedFile *file) * Note that the contents may not be zero-terminated, * even if the #GMappedFile is backed by a text file. * - * Returns: the contents of @file. + * If the file is empty then %NULL is returned. + * + * Returns: the contents of @file, or %NULL. * * Since: 2.8 */ @@ -250,29 +349,79 @@ g_mapped_file_get_contents (GMappedFile *file) * g_mapped_file_free: * @file: a #GMappedFile * - * Unmaps the buffer of @file and frees it. + * This call existed before #GMappedFile had refcounting and is currently + * exactly the same as g_mapped_file_unref(). * * Since: 2.8 + * Deprecated:2.22: Use g_mapped_file_unref() instead. */ void g_mapped_file_free (GMappedFile *file) { - g_return_if_fail (file != NULL); + g_mapped_file_unref (file); +} - if (file->length) - { -#ifdef HAVE_MMAP - munmap (file->contents, file->length); -#endif -#ifdef G_OS_WIN32 - UnmapViewOfFile (file->contents); - CloseHandle (file->mapping); -#endif - } +/** + * g_mapped_file_ref: + * @file: a #GMappedFile + * + * Increments the reference count of @file by one. It is safe to call + * this function from any thread. + * + * Returns: the passed in #GMappedFile. + * + * Since: 2.22 + **/ +GMappedFile * +g_mapped_file_ref (GMappedFile *file) +{ + g_return_val_if_fail (file != NULL, NULL); - g_free (file); + g_atomic_int_inc (&file->ref_count); + + return file; } +/** + * g_mapped_file_unref: + * @file: a #GMappedFile + * + * Decrements the reference count of @file by one. If the reference count + * drops to 0, unmaps the buffer of @file and frees it. + * + * It is safe to call this function from any thread. + * + * Since 2.22 + **/ +void +g_mapped_file_unref (GMappedFile *file) +{ + g_return_if_fail (file != NULL); -#define __G_MAPPED_FILE_C__ -#include "galiasdef.c" + if (g_atomic_int_dec_and_test (&file->ref_count)) + g_mapped_file_destroy (file); +} + +/** + * g_mapped_file_get_bytes: + * @file: a #GMappedFile + * + * Creates a new #GBytes which references the data mapped from @file. + * The mapped contents of the file must not be modified after creating this + * bytes object, because a #GBytes should be immutable. + * + * Returns: (transfer full): A newly allocated #GBytes referencing data + * from @file + * + * Since: 2.34 + **/ +GBytes * +g_mapped_file_get_bytes (GMappedFile *file) +{ + g_return_val_if_fail (file != NULL, NULL); + + return g_bytes_new_with_free_func (file->contents, + file->length, + (GDestroyNotify) g_mapped_file_unref, + g_mapped_file_ref (file)); +}