GraphicsMagick: coders/tga.c TGA footer is read, currently used ...

changeset 33acd8182934 in /hg/GraphicsMagick
details: http://hg.GraphicsMagick.org/hg/GraphicsMagick?cmd=changeset;node=33acd8182934
summary: coders/tga.c TGA footer is read, currently used for logs only.

diffstat:

 ChangeLog    |   8 ++++++--
 coders/tga.c |  55 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 60 insertions(+), 3 deletions(-)

diffs (121 lines):

diff -r 95f1225117f6 -r 33acd8182934 ChangeLog
--- a/ChangeLog	Sun Oct 02 09:41:49 2022 -0500
+++ b/ChangeLog	Mon Oct 03 00:22:15 2022 +0200
@@ -1,3 +1,7 @@
+2022-10-03    Fojtik Jaroslav  <[email protected]>
+
+        * coders/tga.c TGA footer is read, currently used for logs only.
+
 2022-10-02  Bob Friesenhahn  <[email protected]>
 
 	* scripts/rst2html5.py: Fix from Mark Mitchell to deal with RST
@@ -29,11 +33,11 @@
 
 2022-10-01    Fojtik Jaroslav  <[email protected]>
 
-        * coders/tga.c Monochromatic TGA could be written.
+        * coders/tga.c Monochromatic bilevel TGA could be written.
 
 2022-09-29    Fojtik Jaroslav  <[email protected]>
 
-        * coders/tga.c Monochromatic TGA could be read.
+        * coders/tga.c Monochromatic bilevel TGA could be read.
 
 2022-09-28    Fojtik Jaroslav  <[email protected]>
 
diff -r 95f1225117f6 -r 33acd8182934 coders/tga.c
--- a/coders/tga.c	Sun Oct 02 09:41:49 2022 -0500
+++ b/coders/tga.c	Mon Oct 03 00:22:15 2022 +0200
@@ -112,6 +112,17 @@
     Top right           |   1   |   1
 */
 
+
+typedef struct _TGAFooter
+{
+    magick_uint32_t ExtensionOffset;
+    magick_uint32_t DevelopperDirOffset;
+    char Signature[17];		/* 16 official bytes + zero terminator. */
+    char Dot;
+    char Terminator;
+} TGAFooter;
+
+
 
 static void LogTGAInfo(const TGAInfo *tga_info)
 {
@@ -164,9 +175,22 @@
                         tga_info->width, tga_info->height,
                         (unsigned int) tga_info->bits_per_pixel,
                         tga_info->attributes,attribute_bits,OrientationTypeToString(orientation));
+}
 
+
+static void LogTGAFooter(const TGAFooter *ptga_footer)
+{
+ (void) LogMagickEvent(CoderEvent,GetMagickModule(),
+                        "Targa Footer:\n"
+                        "    ExtensionOffset     : %u\n"
+                        "    DevelopperDirOffset : %u\n"
+                        "    Signature           : %s\n",
+                               ptga_footer->ExtensionOffset,
+                               ptga_footer->DevelopperDirOffset,
+			       ptga_footer->Signature);
 }
 
+
 static unsigned int ReadBlobLSBShortFromBuffer(unsigned char* buffer, size_t* readerpos)
 {
   unsigned int
@@ -218,7 +242,6 @@
 %
 %    o exception: return any errors or warnings in this structure.
 %
-%
 */
 static Image *ReadTGAImage(const ImageInfo *image_info,ExceptionInfo *exception)
 {
@@ -246,6 +269,7 @@
 
   TGAInfo
     tga_info;
+  TGAFooter tga_footer;
 
   unsigned char
     runlength;
@@ -291,6 +315,35 @@
   tga_info.colormap_type=(unsigned char)ReadBlobByteFromBuffer(readbuffer, &readbufferpos);
   tga_info.image_type=(unsigned char)ReadBlobByteFromBuffer(readbuffer, &readbufferpos);
 
+  memset(&tga_footer, 0, sizeof(tga_footer));
+  if(BlobIsSeekable(image)
+     && image->logging)		/* TODO: Erase this line, footer is not doing anything usefull yet, logging only. */
+  {
+    status = MagickTrue;
+    SeekBlob(image,-26, SEEK_END);
+    tga_footer.ExtensionOffset = ReadBlobLSBLong(image);
+    tga_footer.DevelopperDirOffset = ReadBlobLSBLong(image);
+    if(ReadBlob(image, 16, tga_footer.Signature) != 16) status=MagickFail;
+    else
+    {
+      if((tga_footer.Dot=ReadBlobByte(image)) != '.') status=MagickFail;
+      if((tga_footer.Terminator=ReadBlobByte(image)) != 0) status=MagickFail;
+    }
+
+    if(status == MagickTrue)
+    {
+      if(image->logging) LogTGAFooter(&tga_footer);
+      if(strncmp(tga_footer.Signature,"TRUEVISION-XFILE",16)) status=MagickFail;
+    }
+
+    if(status != MagickTrue)	// Footer is invalid.
+    {
+      memset(&tga_footer, 0, sizeof(tga_footer));
+      status = MagickTrue;
+    }
+    SeekBlob(image,3,SEEK_SET);
+  }
+
   do
     {
       if (((tga_info.image_type != TGAColormap) &&