diff -r 000000000000 -r e4d67989cc36 glib/libglib/src/gmappedfile.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/glib/libglib/src/gmappedfile.c Tue Feb 02 02:01:42 2010 +0200 @@ -0,0 +1,282 @@ +/* GLIB - Library of useful routines for C programming + * gmappedfile.c: Simplified wrapper around the mmap() function. + * + * Copyright 2005 Matthias Clasen + * Portions copyright (c) 2006 Nokia Corporation. All rights reserved. + * + * 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 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, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 02111-1307, USA. + */ + +#include "config.h" + +#include +#include +#include +#include +#ifdef HAVE_UNISTD_H +#include +#endif +#ifdef HAVE_MMAP +#include +#endif + +#include "glibconfig.h" + +#ifdef G_OS_WIN32 +#include +#include +#endif + +#include "gconvert.h" +#include "gerror.h" +#include "gfileutils.h" +#include "gmappedfile.h" +#include "gmem.h" +#include "gmessages.h" +#include "gstdio.h" +#include "gstrfuncs.h" + +#include "glibintl.h" + +#include "galias.h" + +#ifdef __SYMBIAN32__ +#include "glib.h" +#endif /* __SYMBIAN32__ */ + +#ifndef _O_BINARY +#define _O_BINARY 0 +#endif + +#ifndef MAP_FAILED +#define MAP_FAILED ((void *) -1) +#endif + +struct _GMappedFile +{ + gsize length; + gchar *contents; +#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 + */ +EXPORT_C GMappedFile * +g_mapped_file_new (const gchar *filename, + gboolean writable, + GError **error) +{ + 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) + { + 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 = g_new0 (GMappedFile, 1); + + if (fstat (fd, &st) == -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 get attributes of file '%s': fstat() failed: %s"), + display_filename, + g_strerror (save_errno)); + g_free (display_filename); + goto out; + } + + if (st.st_size == 0) + { + file->length = 0; + file->contents = ""; + close (fd); + return file; + } + + file->contents = MAP_FAILED; + +#ifdef HAVE_MMAP + if (st.st_size > G_MAXSIZE) + { + errno = EINVAL; + } + else + { + file->length = (gsize) st.st_size; + file->contents = (gchar *) mmap (NULL, file->length, + writable ? PROT_READ|PROT_WRITE : PROT_READ, + MAP_PRIVATE, fd, 0); + } +#endif +#ifdef G_OS_WIN32 + file->length = st.st_size; + file->mapping = CreateFileMapping ((HANDLE) _get_osfhandle (fd), NULL, + writable ? PAGE_WRITECOPY : PAGE_READONLY, + 0, 0, + NULL); + if (file->mapping != NULL) + { + file->contents = MapViewOfFile (file->mapping, + writable ? FILE_MAP_COPY : FILE_MAP_READ, + 0, 0, + 0); + if (file->contents == NULL) + { + file->contents = MAP_FAILED; + CloseHandle (file->mapping); + file->mapping = NULL; + } + } +#endif + + + if (file->contents == MAP_FAILED) + { + 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 map file '%s': mmap() failed: %s"), + display_filename, + g_strerror (save_errno)); + g_free (display_filename); + goto out; + } + + close (fd); + return file; + + out: + close (fd); + g_free (file); + + return NULL; +} + +/** + * g_mapped_file_get_length: + * @file: a #GMappedFile + * + * Returns the length of the contents of a #GMappedFile. + * + * Returns: the length of the contents of @file. + * + * Since: 2.8 + */ +EXPORT_C gsize +g_mapped_file_get_length (GMappedFile *file) +{ + g_return_val_if_fail (file != NULL, 0); + + return file->length; +} + +/** + * g_mapped_file_get_contents: + * @file: a #GMappedFile + * + * Returns the contents of a #GMappedFile. + * + * Note that the contents may not be zero-terminated, + * even if the #GMappedFile is backed by a text file. + * + * Returns: the contents of @file. + * + * Since: 2.8 + */ +EXPORT_C gchar * +g_mapped_file_get_contents (GMappedFile *file) +{ + g_return_val_if_fail (file != NULL, NULL); + + return file->contents; +} + +/** + * g_mapped_file_free: + * @file: a #GMappedFile + * + * Unmaps the buffer of @file and frees it. + * + * Since: 2.8 + */ +EXPORT_C void +g_mapped_file_free (GMappedFile *file) +{ + g_return_if_fail (file != NULL); + + if (file->length) + { +#ifdef HAVE_MMAP + munmap (file->contents, file->length); +#endif +#ifdef G_OS_WIN32 + UnmapViewOfFile (file->contents); + CloseHandle (file->mapping); +#endif + } + + g_free (file); +} + + +#define __G_MAPPED_FILE_C__ +#include "galiasdef.c"