X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=deanimate.c;h=3ad4e2bed1404cd60a634c7b3df5c8e56a8d72b6;hp=2233dcc97c90ad35967b6754534ad7d38bca7f04;hb=f6d5412c130de0675288a218d065729380ff33b8;hpb=4a1c090df7a6b35c83f067afacb325b5cb84139a

diff --git a/deanimate.c b/deanimate.c
index 2233dcc9..3ad4e2be 100644
--- a/deanimate.c
+++ b/deanimate.c
@@ -1,16 +1,18 @@
-const char deanimate_rcs[] = "$Id: deanimate.c,v 1.6 2002/03/07 03:46:17 oes Exp $";
+const char deanimate_rcs[] = "$Id: deanimate.c,v 1.19 2008/05/21 15:29:35 fabiankeil Exp $";
 /*********************************************************************
  *
  * File        :  $Source: /cvsroot/ijbswa/current/deanimate.c,v $
  *
- * Purpose     :  Declares functions to deanimate GIF images on the fly.
+ * Purpose     :  Declares functions to manipulate binary images on the
+ *                fly.  High-level functions include:
+ *                  - Deanimation of GIF images
  *                
  *                Functions declared include: gif_deanimate, buf_free,
- *                buf_copy,  buf_getbyte, gif_skip_data_block, and
- *                gif_extract_image
+ *                buf_copy,  buf_getbyte, gif_skip_data_block
+ *                and gif_extract_image
  *
- * Copyright   :  Written by and Copyright (C) 2001 by the the SourceForge
- *                IJBSWA team.  http://ijbswa.sourceforge.net
+ * Copyright   :  Written by and Copyright (C) 2001 - 2004, 2006 by the
+ *                SourceForge Privoxy team. http://www.privoxy.org/
  *
  *                Based on the GIF file format specification (see
  *                http://tronche.com/computer-graphics/gif/gif89a.html)
@@ -35,36 +37,15 @@ const char deanimate_rcs[] = "$Id: deanimate.c,v 1.6 2002/03/07 03:46:17 oes Exp
  *                or write to the Free Software Foundation, Inc., 59
  *                Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  *
- * Revisions   :
- *    $Log: deanimate.c,v $
- *    Revision 1.6  2002/03/07 03:46:17  oes
- *    Fixed compiler warnings
- *
- *    Revision 1.5  2001/09/10 10:16:06  oes
- *    Silenced compiler warnings
- *
- *    Revision 1.4  2001/07/18 12:28:49  oes
- *    - Added feature for extracting the first frame
- *      to gif_deanimate
- *    - Separated image buffer extension into buf_extend
- *    - Extended gif deanimation to GIF87a (untested!)
- *    - Cosmetics
- *
- *    Revision 1.3  2001/07/15 13:57:50  jongfoster
- *    Adding #includes string.h and miscutil.h
- *
- *    Revision 1.2  2001/07/13 13:46:20  oes
- *    Introduced GIF deanimation feature
- *
- *
  **********************************************************************/
-
+
 
 #include "config.h"
 
 #include <string.h>
 #include <fcntl.h>
 
+#include "errlog.h"
 #include "project.h"
 #include "deanimate.h"
 #include "miscutil.h"
@@ -111,16 +92,16 @@ void buf_free(struct binbuffer *buf)
  *          2  :  length = Desired minimum size
  *                
  *
- * Returns     :  0 on success, 1 on failiure.
+ * Returns     :  0 on success, 1 on failure.
  *
  *********************************************************************/
-int buf_extend(struct binbuffer *buf, size_t length)
+static int buf_extend(struct binbuffer *buf, size_t length)
 {
    char *newbuf;
 
    if (buf->offset + length > buf->size)
    {
-      buf->size = ((buf->size + length + 1023) & ~1023);
+      buf->size = ((buf->size + length + (size_t)1023) & ~(size_t)1023);
       newbuf = (char *)realloc(buf->buffer, buf->size);
 
       if (newbuf == NULL)
@@ -152,10 +133,10 @@ int buf_extend(struct binbuffer *buf, size_t length)
  *          2  :  dst = Pointer to the destination binbuffer
  *          3  :  length = Number of bytes to be copied
  *
- * Returns     :  0 on success, 1 on failiure.
+ * Returns     :  0 on success, 1 on failure.
  *
  *********************************************************************/
-int buf_copy(struct binbuffer *src, struct binbuffer *dst, size_t length)
+static int buf_copy(struct binbuffer *src, struct binbuffer *dst, size_t length)
 {
 
    /*
@@ -195,13 +176,13 @@ int buf_copy(struct binbuffer *src, struct binbuffer *dst, size_t length)
  *                given offset
  *
  * Parameters  :
- *          1  :  buf = Pointer to the source binbuffer
+ *          1  :  src = Pointer to the source binbuffer
  *          2  :  offset = Offset to the desired byte
  *
- * Returns     :  The byte on success, or 0 on failiure
+ * Returns     :  The byte on success, or 0 on failure
  *
  *********************************************************************/
-unsigned char buf_getbyte(struct binbuffer *src, size_t offset)
+static unsigned char buf_getbyte(const struct binbuffer *src, size_t offset)
 {
    if (src->offset + offset < src->size)
    {
@@ -227,10 +208,10 @@ unsigned char buf_getbyte(struct binbuffer *src, size_t offset)
  * Parameters  :
  *          1  :  buf = Pointer to the binbuffer
  *
- * Returns     :  0 on success, or 1 on failiure
+ * Returns     :  0 on success, or 1 on failure
  *
  *********************************************************************/
-int gif_skip_data_block(struct binbuffer *buf)
+static int gif_skip_data_block(struct binbuffer *buf)
 {
    unsigned char c;
 
@@ -239,9 +220,10 @@ int gif_skip_data_block(struct binbuffer *buf)
     * by a one-byte length field, with the last chunk having
     * zero length.
     */
-   while((c = buf_getbyte(buf, 0)))
+   while((c = buf_getbyte(buf, 0)) != '\0')
    {
-      if ((buf->offset += c + 1) >= buf->size - 1)
+      buf->offset += (size_t)c + 1;
+      if (buf->offset >= buf->size - 1)
       {
          return 1;
       }
@@ -266,13 +248,13 @@ int gif_skip_data_block(struct binbuffer *buf)
  *          1  :  src = Pointer to the source binbuffer
  *          2  :  dst = Pointer to the destination binbuffer
  *
- * Returns     :  0 on success, or 1 on failiure
+ * Returns     :  0 on success, or 1 on failure
  *
  *********************************************************************/
-int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
+static int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
 {
    unsigned char c;
-   
+
    /*
     * Remember the colormap flag and copy the image head
     */
@@ -287,7 +269,14 @@ int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
     */
    if (c & 0x80)
    {
-      if (buf_copy(src, dst, (size_t) 3 * (1 << ((c & 0x07) + 1))))
+      int map_length = 3 * (1 << ((c & 0x07) + 1));
+      if (map_length <= 0)
+      {
+         log_error(LOG_LEVEL_DEANIMATE,
+            "colormap length = %d (%c)?", map_length, c);
+         return 1;
+      }
+      if (buf_copy(src, dst, (size_t)map_length))
       {
          return 1;
       }           
@@ -297,7 +286,7 @@ int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
    /*
     * Copy the image chunk by chunk.
     */
-   while((c = buf_getbyte(src, 0)))
+   while((c = buf_getbyte(src, 0)) != '\0')
    {
       if (buf_copy(src, dst, 1 + (size_t) c)) return 1;
    }
@@ -331,7 +320,7 @@ int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
  *          3  :  get_first_image = Flag: If set, get the first image
  *                                        If unset (default), get the last
  *
- * Returns     :  0 on success, or 1 on failiure
+ * Returns     :  0 on success, or 1 on failure
  *
  *********************************************************************/
 int gif_deanimate(struct binbuffer *src, struct binbuffer *dst, int get_first_image)
@@ -366,7 +355,14 @@ int gif_deanimate(struct binbuffer *src, struct binbuffer *dst, int get_first_im
     */
    if(c & 0x80)
    {
-      if (buf_copy(src, dst, (size_t) 3 * (1 << ((c & 0x07) + 1))))
+      int map_length = 3 * (1 << ((c & 0x07) + 1));
+      if (map_length <= 0)
+      {
+         log_error(LOG_LEVEL_DEANIMATE,
+            "colormap length = %d (%c)?", map_length, c);
+         return 1;
+      }
+      if (buf_copy(src, dst, (size_t)map_length))
       {
          return 1;
       }