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diff --git a/src/cairo-image-info.c b/src/cairo-image-info.c
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+/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
+/* cairo - a vector graphics library with display and print output
+ *
+ * Copyright © 2008 Adrian Johnson
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it either under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation
+ * (the "LGPL") or, at your option, under the terms of the Mozilla
+ * Public License Version 1.1 (the "MPL"). If you do not alter this
+ * notice, a recipient may use your version of this file under either
+ * the MPL or the LGPL.
+ *
+ * You should have received a copy of the LGPL along with this library
+ * in the file COPYING-LGPL-2.1; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
+ * You should have received a copy of the MPL along with this library
+ * in the file COPYING-MPL-1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
+ * OF ANY KIND, either express or implied. See the LGPL or the MPL for
+ * the specific language governing rights and limitations.
+ *
+ * The Original Code is the cairo graphics library.
+ *
+ * The Initial Developer of the Original Code is Adrian Johnson.
+ *
+ * Contributor(s):
+ * Adrian Johnson <ajohnson@redneon.com>
+ */
+
+#include "cairoint.h"
+
+#include "cairo-error-private.h"
+#include "cairo-image-info-private.h"
+
+/* JPEG (image/jpeg)
+ *
+ * http://www.w3.org/Graphics/JPEG/itu-t81.pdf
+ */
+
+/* Markers with no parameters. All other markers are followed by a two
+ * byte length of the parameters. */
+#define TEM 0x01
+#define RST_begin 0xd0
+#define RST_end 0xd7
+#define SOI 0xd8
+#define EOI 0xd9
+
+/* Start of frame markers. */
+#define SOF0 0xc0
+#define SOF1 0xc1
+#define SOF2 0xc2
+#define SOF3 0xc3
+#define SOF5 0xc5
+#define SOF6 0xc6
+#define SOF7 0xc7
+#define SOF9 0xc9
+#define SOF10 0xca
+#define SOF11 0xcb
+#define SOF13 0xcd
+#define SOF14 0xce
+#define SOF15 0xcf
+
+static const unsigned char *
+_jpeg_skip_segment (const unsigned char *p)
+{
+ int len;
+
+ p++;
+ len = (p[0] << 8) | p[1];
+
+ return p + len;
+}
+
+static void
+_jpeg_extract_info (cairo_image_info_t *info, const unsigned char *p)
+{
+ info->width = (p[6] << 8) + p[7];
+ info->height = (p[4] << 8) + p[5];
+ info->num_components = p[8];
+ info->bits_per_component = p[3];
+}
+
+cairo_int_status_t
+_cairo_image_info_get_jpeg_info (cairo_image_info_t *info,
+ const unsigned char *data,
+ long length)
+{
+ const unsigned char *p = data;
+
+ while (p + 1 < data + length) {
+ if (*p != 0xff)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+ p++;
+
+ switch (*p) {
+ /* skip fill bytes */
+ case 0xff:
+ p++;
+ break;
+
+ case TEM:
+ case SOI:
+ case EOI:
+ p++;
+ break;
+
+ case SOF0:
+ case SOF1:
+ case SOF2:
+ case SOF3:
+ case SOF5:
+ case SOF6:
+ case SOF7:
+ case SOF9:
+ case SOF10:
+ case SOF11:
+ case SOF13:
+ case SOF14:
+ case SOF15:
+ /* Start of frame found. Extract the image parameters. */
+ if (p + 8 > data + length)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ _jpeg_extract_info (info, p);
+ return CAIRO_STATUS_SUCCESS;
+
+ default:
+ if (*p >= RST_begin && *p <= RST_end) {
+ p++;
+ break;
+ }
+
+ if (p + 2 > data + length)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ p = _jpeg_skip_segment (p);
+ break;
+ }
+ }
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+/* JPEG 2000 (image/jp2)
+ *
+ * http://www.jpeg.org/public/15444-1annexi.pdf
+ */
+
+#define JPX_FILETYPE 0x66747970
+#define JPX_JP2_HEADER 0x6A703268
+#define JPX_IMAGE_HEADER 0x69686472
+
+static const unsigned char _jpx_signature[] = {
+ 0x00, 0x00, 0x00, 0x0c, 0x6a, 0x50, 0x20, 0x20, 0x0d, 0x0a, 0x87, 0x0a
+};
+
+static const unsigned char *
+_jpx_next_box (const unsigned char *p)
+{
+ return p + get_unaligned_be32 (p);
+}
+
+static const unsigned char *
+_jpx_get_box_contents (const unsigned char *p)
+{
+ return p + 8;
+}
+
+static cairo_bool_t
+_jpx_match_box (const unsigned char *p, const unsigned char *end, uint32_t type)
+{
+ uint32_t length;
+
+ if (p + 8 < end) {
+ length = get_unaligned_be32 (p);
+ if (get_unaligned_be32 (p + 4) == type && p + length < end)
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+static const unsigned char *
+_jpx_find_box (const unsigned char *p, const unsigned char *end, uint32_t type)
+{
+ while (p < end) {
+ if (_jpx_match_box (p, end, type))
+ return p;
+ p = _jpx_next_box (p);
+ }
+
+ return NULL;
+}
+
+static void
+_jpx_extract_info (const unsigned char *p, cairo_image_info_t *info)
+{
+ info->height = get_unaligned_be32 (p);
+ info->width = get_unaligned_be32 (p + 4);
+ info->num_components = (p[8] << 8) + p[9];
+ info->bits_per_component = p[10];
+}
+
+cairo_int_status_t
+_cairo_image_info_get_jpx_info (cairo_image_info_t *info,
+ const unsigned char *data,
+ unsigned long length)
+{
+ const unsigned char *p = data;
+ const unsigned char *end = data + length;
+
+ /* First 12 bytes must be the JPEG 2000 signature box. */
+ if (length < ARRAY_LENGTH(_jpx_signature) ||
+ memcmp(p, _jpx_signature, ARRAY_LENGTH(_jpx_signature)) != 0)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ p += ARRAY_LENGTH(_jpx_signature);
+
+ /* Next box must be a File Type Box */
+ if (! _jpx_match_box (p, end, JPX_FILETYPE))
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ p = _jpx_next_box (p);
+
+ /* Locate the JP2 header box. */
+ p = _jpx_find_box (p, end, JPX_JP2_HEADER);
+ if (!p)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ /* Step into the JP2 header box. First box must be the Image
+ * Header */
+ p = _jpx_get_box_contents (p);
+ if (! _jpx_match_box (p, end, JPX_IMAGE_HEADER))
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ /* Get the image info */
+ p = _jpx_get_box_contents (p);
+ _jpx_extract_info (p, info);
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+/* PNG (image/png)
+ *
+ * http://www.w3.org/TR/2003/REC-PNG-20031110/
+ */
+
+#define PNG_IHDR 0x49484452
+
+static const unsigned char _png_magic[8] = { 137, 80, 78, 71, 13, 10, 26, 10 };
+
+cairo_int_status_t
+_cairo_image_info_get_png_info (cairo_image_info_t *info,
+ const unsigned char *data,
+ unsigned long length)
+{
+ const unsigned char *p = data;
+ const unsigned char *end = data + length;
+
+ if (length < 8 || memcmp (data, _png_magic, 8) != 0)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ p += 8;
+
+ /* The first chunk must be IDHR. IDHR has 13 bytes of data plus
+ * the 12 bytes of overhead for the chunk. */
+ if (p + 13 + 12 > end)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ p += 4;
+ if (get_unaligned_be32 (p) != PNG_IHDR)
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+
+ p += 4;
+ info->width = get_unaligned_be32 (p);
+ p += 4;
+ info->height = get_unaligned_be32 (p);
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+static const unsigned char *
+_jbig2_find_data_end (const unsigned char *p,
+ const unsigned char *end,
+ int type)
+{
+ unsigned char end_seq[2];
+ int mmr;
+
+ /* Segments of type "Immediate generic region" may have an
+ * unspecified data length. The JBIG2 specification specifies the
+ * method to find the end of the data for these segments. */
+ if (type == 36 || type == 38 || type == 39) {
+ if (p + 18 < end) {
+ mmr = p[17] & 0x01;
+ if (mmr) {
+ /* MMR encoding ends with 0x00, 0x00 */
+ end_seq[0] = 0x00;
+ end_seq[1] = 0x00;
+ } else {
+ /* Template encoding ends with 0xff, 0xac */
+ end_seq[0] = 0xff;
+ end_seq[1] = 0xac;
+ }
+ p += 18;
+ while (p < end) {
+ if (p[0] == end_seq[0] && p[1] == end_seq[1]) {
+ /* Skip the 2 terminating bytes and the 4 byte row count that follows. */
+ p += 6;
+ if (p < end)
+ return p;
+ }
+ p++;
+ }
+ }
+ }
+
+ return NULL;
+}
+
+static const unsigned char *
+_jbig2_get_next_segment (const unsigned char *p,
+ const unsigned char *end,
+ int *type,
+ const unsigned char **data,
+ unsigned long *data_len)
+{
+ unsigned long seg_num;
+ cairo_bool_t big_page_size;
+ int num_segs;
+ int ref_seg_bytes;
+ int referred_size;
+
+ if (p + 6 >= end)
+ return NULL;
+
+ seg_num = get_unaligned_be32 (p);
+ *type = p[4] & 0x3f;
+ big_page_size = (p[4] & 0x40) != 0;
+ p += 5;
+
+ num_segs = p[0] >> 5;
+ if (num_segs == 7) {
+ num_segs = get_unaligned_be32 (p) & 0x1fffffff;
+ ref_seg_bytes = 4 + ((num_segs + 1)/8);
+ } else {
+ ref_seg_bytes = 1;
+ }
+ p += ref_seg_bytes;
+
+ if (seg_num <= 256)
+ referred_size = 1;
+ else if (seg_num <= 65536)
+ referred_size = 2;
+ else
+ referred_size = 4;
+
+ p += num_segs * referred_size;
+ p += big_page_size ? 4 : 1;
+ if (p + 4 >= end)
+ return NULL;
+
+ *data_len = get_unaligned_be32 (p);
+ p += 4;
+ *data = p;
+
+ if (*data_len == 0xffffffff) {
+ /* if data length is -1 we have to scan through the data to find the end */
+ p = _jbig2_find_data_end (*data, end, *type);
+ if (!p || p >= end)
+ return NULL;
+
+ *data_len = p - *data;
+ } else {
+ p += *data_len;
+ }
+
+ if (p < end)
+ return p;
+ else
+ return NULL;
+}
+
+static void
+_jbig2_extract_info (cairo_image_info_t *info, const unsigned char *p)
+{
+ info->width = get_unaligned_be32 (p);
+ info->height = get_unaligned_be32 (p + 4);
+ info->num_components = 1;
+ info->bits_per_component = 1;
+}
+
+cairo_int_status_t
+_cairo_image_info_get_jbig2_info (cairo_image_info_t *info,
+ const unsigned char *data,
+ unsigned long length)
+{
+ const unsigned char *p = data;
+ const unsigned char *end = data + length;
+ int seg_type;
+ const unsigned char *seg_data;
+ unsigned long seg_data_len;
+
+ while (p && p < end) {
+ p = _jbig2_get_next_segment (p, end, &seg_type, &seg_data, &seg_data_len);
+ if (p && seg_type == 48 && seg_data_len > 8) {
+ /* page information segment */
+ _jbig2_extract_info (info, seg_data);
+ return CAIRO_STATUS_SUCCESS;
+ }
+ }
+
+ return CAIRO_INT_STATUS_UNSUPPORTED;
+}