ensure code will compile with an ANSI-C compiler

ImageMagick · Jan 28, 2023 · 2c240b7 · 2c240b7
1 parent 25d201d
commit 2c240b7
Showing 1 changed file with 13 additions and 0 deletions.
diff --git a/coders/heic.c b/coders/heic.c
@@ -221,13 +221,26 @@ static MagickBooleanType ReadHEICExifProfile(Image *image,
       /*
         Extract Exif profile.
       */
+      size_t exif_length = GetStringInfoLength(exif_profile);
+      unsigned char *exif_datum = GetStringInfoDatum(exif_profile);
       StringInfo *snippet = SplitStringInfo(exif_profile,4);
       unsigned int offset = 0;
       offset|=(unsigned int) (*(GetStringInfoDatum(snippet)+0)) << 24;
       offset|=(unsigned int) (*(GetStringInfoDatum(snippet)+1)) << 16;
       offset|=(unsigned int) (*(GetStringInfoDatum(snippet)+2)) << 8;
       offset|=(unsigned int) (*(GetStringInfoDatum(snippet)+3)) << 0;
       snippet=DestroyStringInfo(snippet);
+      /*
+        Strip any EOI marker if payload starts with a JPEG marker.
+      */
+      if ((exif_length > 2) &&
+          ((memcmp(exif_datum,"\0xFF\0xD8",2) == 0) ||
+           (memcmp(exif_datum,"\0xFF\0xE1",2) == 0)) &&
+           memcmp(exif_datum+exif_length-2,"\0xFF\0xD9",2) == 0)
+        SetStringInfoLength(exif_profile,exif_length-2);
+      /*
+        Skip to actual Exif payload.
+      */
       if (offset < GetStringInfoLength(exif_profile))
         {
           (void) DestroyStringInfo(SplitStringInfo(exif_profile,offset));