X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=deanimate.c;h=59ed56e96c25bf64b84c6ea24663248f8392e3f8;hp=b0ba14e9dbb044bb46865b3fb2891fc9f6e696e3;hb=18e3588a109908e89842c0d79338fbdc5b812949;hpb=29aff70c9341505c82124964f20e2213dd04de81

diff --git a/deanimate.c b/deanimate.c
index b0ba14e9..59ed56e9 100644
--- a/deanimate.c
+++ b/deanimate.c
@@ -1,4 +1,4 @@
-const char deanimate_rcs[] = "$Id: deanimate.c,v 1.2 2001/07/13 13:46:20 oes Exp $";
+const char deanimate_rcs[] = "$Id: deanimate.c,v 1.11 2002/03/26 22:29:54 swa Exp $";
 /*********************************************************************
  *
  * File        :  $Source: /cvsroot/ijbswa/current/deanimate.c,v $
@@ -9,8 +9,8 @@ const char deanimate_rcs[] = "$Id: deanimate.c,v 1.2 2001/07/13 13:46:20 oes Exp
  *                buf_copy,  buf_getbyte, gif_skip_data_block, and
  *                gif_extract_image
  *
- * Copyright   :  Written by and Copyright (C) 2001 Andreas S. Oesterhelt
- *                for the SourceForge IJBSWA team. http://ijbswa.sourceforge.net
+ * Copyright   :  Written by and Copyright (C) 2001 by the the SourceForge
+ *                Privoxy team. http://www.privoxy.org/
  *
  *                Based on the GIF file format specification (see
  *                http://tronche.com/computer-graphics/gif/gif89a.html)
@@ -37,6 +37,37 @@ const char deanimate_rcs[] = "$Id: deanimate.c,v 1.2 2001/07/13 13:46:20 oes Exp
  *
  * Revisions   :
  *    $Log: deanimate.c,v $
+ *    Revision 1.11  2002/03/26 22:29:54  swa
+ *    we have a new homepage!
+ *
+ *    Revision 1.10  2002/03/24 13:25:43  swa
+ *    name change related issues
+ *
+ *    Revision 1.9  2002/03/13 00:27:04  jongfoster
+ *    Killing warnings
+ *
+ *    Revision 1.8  2002/03/09 19:42:47  jongfoster
+ *    Fixing more warnings
+ *
+ *    Revision 1.7  2002/03/08 17:46:04  jongfoster
+ *    Fixing int/size_t warnings
+ *
+ *    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
  *
@@ -81,6 +112,48 @@ void buf_free(struct binbuffer *buf)
 }
 
 
+/*********************************************************************
+ * 
+ * Function    :  buf_extend
+ *
+ * Description :  Ensure that a given binbuffer can hold a given amount
+ *                of bytes, by reallocating its buffer if necessary.
+ *                Allocate new mem in chunks of 1024 bytes, so we don't
+ *                have to realloc() too often.
+ *
+ * Parameters  :
+ *          1  :  buf = Pointer to the binbuffer
+ *          2  :  length = Desired minimum size
+ *                
+ *
+ * Returns     :  0 on success, 1 on failiure.
+ *
+ *********************************************************************/
+int buf_extend(struct binbuffer *buf, size_t length)
+{
+   char *newbuf;
+
+   if (buf->offset + length > buf->size)
+   {
+      buf->size = ((buf->size + length + (size_t)1023) & ~(size_t)1023);
+      newbuf = (char *)realloc(buf->buffer, buf->size);
+
+      if (newbuf == NULL)
+      {
+         freez(buf->buffer);
+         return 1;
+      }
+      else
+      {
+         buf->buffer = newbuf;
+         return 0;
+      }
+   }
+   return 0;
+
+}
+
+
 /*********************************************************************
  * 
  * Function    :  buf_copy
@@ -97,9 +170,8 @@ void buf_free(struct binbuffer *buf)
  * Returns     :  0 on success, 1 on failiure.
  *
  *********************************************************************/
-int buf_copy(struct binbuffer *src, struct binbuffer *dst, int length)
+int buf_copy(struct binbuffer *src, struct binbuffer *dst, size_t length)
 {
-   char *p;
 
    /*
     * Sanity check: Can't copy more data than we have
@@ -110,20 +182,11 @@ int buf_copy(struct binbuffer *src, struct binbuffer *dst, int length)
    }
 
    /*
-    * If dst can't hold the new data, get mem first. (In chunks
-    * of 1000 bytes, so we don't have to realloc() too often)
+    * Ensure that dst can hold the new data
     */
-   if (dst->offset + length > dst->size)
+   if (buf_extend(dst, length)) 
    {
-      dst->size = dst->size + length + 1000 - (dst->size + length) % 1000;
-      p = dst->buffer;
-      dst->buffer = (char *)realloc(dst->buffer, dst->size);
-
-      if (dst->buffer == NULL)
-      {
-         free(p);
-         return 1;
-      }
+      return 1;
    }
 
    /*
@@ -147,13 +210,13 @@ int buf_copy(struct binbuffer *src, struct binbuffer *dst, int 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
  *
  *********************************************************************/
-unsigned char buf_getbyte(struct binbuffer *src, int offset)
+unsigned char buf_getbyte(struct binbuffer *src, size_t offset)
 {
    if (src->offset + offset < src->size)
    {
@@ -173,7 +236,7 @@ unsigned char buf_getbyte(struct binbuffer *src, int offset)
  *
  * Description :  Safely advances the offset of a given struct binbuffer
  *                that contains a GIF image and whose offset is
- *                positioned at the start of a data block behind
+ *                positioned at the start of a data block, behind
  *                that block.
  *
  * Parameters  :
@@ -191,7 +254,7 @@ 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)
       {
@@ -239,7 +302,7 @@ int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
     */
    if (c & 0x80)
    {
-      if (buf_copy(src, dst, 3 * (1 << ((c & 0x07) + 1))))
+      if (buf_copy(src, dst, (size_t) 3 * (1 << ((c & 0x07) + 1))))
       {
          return 1;
       }           
@@ -249,16 +312,16 @@ 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, c + 1)) return 1;
+      if (buf_copy(src, dst, 1 + (size_t) c)) return 1;
    }
    if (buf_copy(src, dst, 1)) return 1;
 
    /*
     * Trim and rewind the dst buffer
     */
-   dst->buffer = (char *)realloc(dst->buffer, dst->offset);
+   if (NULL == (dst->buffer = (char *)realloc(dst->buffer, dst->offset))) return 1;
    dst->size = dst->offset;
    dst->offset = 0;
 
@@ -280,11 +343,13 @@ int gif_extract_image(struct binbuffer *src, struct binbuffer *dst)
  * Parameters  :
  *          1  :  src = Pointer to the source binbuffer
  *          2  :  dst = Pointer to the destination binbuffer
+ *          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
  *
  *********************************************************************/
-int gif_deanimate(struct binbuffer *src, struct binbuffer *dst)
+int gif_deanimate(struct binbuffer *src, struct binbuffer *dst, int get_first_image)
 {
    unsigned char c;
    struct binbuffer *image;
@@ -299,9 +364,8 @@ int gif_deanimate(struct binbuffer *src, struct binbuffer *dst)
    /*
     * Check & copy GIF header 
     */
-   if (strncmp(src->buffer, "GIF89a", 6)) 
+   if (strncmp(src->buffer, "GIF89a", 6) && strncmp(src->buffer, "GIF87a", 6)) 
    {
-      fprintf(stderr, "This is not a GIF98a!\n");
       return 1;
    }
    else
@@ -317,7 +381,7 @@ int gif_deanimate(struct binbuffer *src, struct binbuffer *dst)
     */
    if(c & 0x80)
    {
-      if (buf_copy(src, dst, 3 * (1 << ((c & 0x07) + 1))))
+      if (buf_copy(src, dst, (size_t) 3 * (1 << ((c & 0x07) + 1))))
       {
          return 1;
       }
@@ -343,22 +407,15 @@ int gif_deanimate(struct binbuffer *src, struct binbuffer *dst)
           *  End-of-GIF Marker: Append current image and return
           */
       case 0x3b:
-         if (buf_copy(image, dst, image->size) || buf_copy(src, dst, 1))
-         {
-            goto failed;
-         }
-         buf_free(image);
-         return(0);
+         goto write;
 
          /* 
-          * Image block: Extract to current image buffer
+          * Image block: Extract to current image buffer.
           */
       case 0x2c:
          image->offset = 0;
-         if (gif_extract_image(src, image))
-         {
-            goto failed;
-         }
+         if (gif_extract_image(src, image)) goto failed;
+         if (get_first_image) goto write;
          continue;
 
          /*
@@ -375,6 +432,7 @@ int gif_deanimate(struct binbuffer *src, struct binbuffer *dst)
             image->offset = 0;
             if (buf_copy(src, image, 8) || buf_getbyte(src, 0) != 0x2c) goto failed;
             if (gif_extract_image(src, image)) goto failed;
+            if (get_first_image) goto write;
             continue;
 
             /*
@@ -425,6 +483,17 @@ failed:
    buf_free(image);
    return 1;
 
+   /*
+    * Append the current image to dst and return
+    */
+
+write:
+   if (buf_copy(image, dst, image->size)) goto failed;
+   if (buf_extend(dst, 1)) goto failed;
+   *(dst->buffer + dst->offset++) = 0x3b;
+   buf_free(image);
+   return 0;
+
 }