Make jpeg loading errors non-fatal.

1 files changed, 35 insertions, 8 deletions

diff --git a/src/renderercommon/tr_image_jpg.c b/src/renderercommon/tr_image_jpg.c
index 2bbcb365..15c280d5 100644
--- a/src/renderercommon/tr_image_jpg.c
+++ b/src/renderercommon/tr_image_jpg.c
@@ -21,6 +21,8 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 ===========================================================================
 */
 
+#include <setjmp.h>
+
 #include "tr_common.h"
 
 /*
@@ -43,16 +45,27 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 #  endif
 #endif
 
-static void __attribute__((__noreturn__)) R_JPGErrorExit(j_common_ptr cinfo)
+/* Catching errors, as done in libjpeg's example.c */
+typedef struct q_jpeg_error_mgr_s
+{
+  struct jpeg_error_mgr pub;  /* "public" fields */
+
+  jmp_buf setjmp_buffer;  /* for return to caller */
+} q_jpeg_error_mgr_t;
+
+static void R_JPGErrorExit(j_common_ptr cinfo)
 {
   char buffer[JMSG_LENGTH_MAX];
+
+  /* cinfo->err really points to a q_jpeg_error_mgr_s struct, so coerce pointer */
+  q_jpeg_error_mgr_t *jerr = (q_jpeg_error_mgr_t *)cinfo->err;
   
   (*cinfo->err->format_message) (cinfo, buffer);
-  
-  /* Let the memory manager delete any temp files before we die */
-  jpeg_destroy(cinfo);
-  
-  ri.Error(ERR_FATAL, "%s", buffer);
+
+  ri.Printf(PRINT_ALL, "R_LoadJPG() error: %s", buffer);
+
+  /* Return control to the setjmp point */
+  longjmp(jerr->setjmp_buffer, 1);
 }
 
 static void R_JPGOutputMessage(j_common_ptr cinfo)
@@ -84,7 +97,7 @@ void R_LoadJPG(const char *filename, unsigned char **pic, int *width, int *heigh
    * Note that this struct must live as long as the main JPEG parameter
    * struct, to avoid dangling-pointer problems.
    */
-  struct jpeg_error_mgr jerr;
+  q_jpeg_error_mgr_t jerr;
   /* More stuff */
   JSAMPARRAY buffer;		/* Output row buffer */
   unsigned int row_stride;	/* physical row width in output buffer */
@@ -116,10 +129,24 @@ void R_LoadJPG(const char *filename, unsigned char **pic, int *width, int *heigh
    * This routine fills in the contents of struct jerr, and returns jerr's
    * address which we place into the link field in cinfo.
    */
-  cinfo.err = jpeg_std_error(&jerr);
+  cinfo.err = jpeg_std_error(&jerr.pub);
   cinfo.err->error_exit = R_JPGErrorExit;
   cinfo.err->output_message = R_JPGOutputMessage;
 
+  /* Establish the setjmp return context for R_JPGErrorExit to use. */
+  if (setjmp(jerr.setjmp_buffer))
+  {
+    /* If we get here, the JPEG code has signaled an error.
+     * We need to clean up the JPEG object, close the input file, and return.
+     */
+    jpeg_destroy_decompress(&cinfo);
+    ri.FS_FreeFile(fbuffer.v);
+
+    /* Append the filename to the error for easier debugging */
+    ri.Printf(PRINT_ALL, ", file %s\n", filename);
+    return;
+  }
+
   /* Now we can initialize the JPEG decompression object. */
   jpeg_create_decompress(&cinfo);