Remove longjmp from the Gif module

The Gif module is only using the longjmp as a way to catch errors, so this CL
makes it use GifDecodeStatus::Error instead.

Change-Id: I9c97e63ed851d2a80e38f1d2cd9e8f297d608cb2
Reviewed-on: https://pdfium-review.googlesource.com/5850
Commit-Queue: Nicolás Peña <npm@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>

1 files changed, 10 insertions, 19 deletions

diff --git a/core/fxcodec/lgif/fx_gif.cpp b/core/fxcodec/lgif/fx_gif.cpp
index 5e257cc2f5..b4fe328f6c 100644
--- a/core/fxcodec/lgif/fx_gif.cpp
+++ b/core/fxcodec/lgif/fx_gif.cpp
@@ -119,8 +119,7 @@ GifDecodeStatus gif_decode_extension(CGifContext* context) {
 
 GifDecodeStatus gif_decode_image_info(CGifContext* context) {
   if (context->width == 0 || context->height == 0) {
-    context->ThrowError("No Image Header Info");
-    NOTREACHED();
+    context->AddError("No Image Header Info");
     return GifDecodeStatus::Error;
   }
   uint32_t skip_size_org = context->skip_size;
@@ -143,9 +142,7 @@ GifDecodeStatus gif_decode_image_info(CGifContext* context) {
           context->width ||
       gif_image->m_ImageInfo.top + gif_image->m_ImageInfo.height >
           context->height) {
-    gif_image = nullptr;
-    context->ThrowError("Image Data Out Of LSD, The File May Be Corrupt");
-    NOTREACHED();
+    context->AddError("Image Data Out Of LSD, The File May Be Corrupt");
     return GifDecodeStatus::Error;
   }
   GifLF* gif_img_info_lf_ptr = (GifLF*)&gif_img_info_ptr->local_flag;
@@ -182,8 +179,7 @@ void gif_decoding_failure_at_tail_cleanup(CGifContext* context,
                                           GifImage* gif_image_ptr) {
   gif_image_ptr->m_ImageRowBuf.clear();
   gif_save_decoding_status(context, GIF_D_STATUS_TAIL);
-  context->ThrowError("Decode Image Data Error");
-  NOTREACHED();
+  context->AddError("Decode Image Data Error");
 }
 
 }  // namespace
@@ -378,8 +374,7 @@ GifDecodeStatus gif_read_header(CGifContext* context) {
 
   if (strncmp(gif_header_ptr->signature, GIF_SIGNATURE, 3) != 0 ||
       gif_header_ptr->version[0] != '8' || gif_header_ptr->version[2] != 'a') {
-    context->ThrowError("Not A Gif Image");
-    NOTREACHED();
+    context->AddError("Not A Gif Image");
     return GifDecodeStatus::Error;
   }
   GifLSD* gif_lsd_ptr = nullptr;
@@ -474,6 +469,7 @@ GifDecodeStatus gif_get_frame(CGifContext* context) {
         ret = gif_decode_image_info(context);
         if (ret != GifDecodeStatus::Success)
           return ret;
+
         continue;
       }
       case GIF_D_STATUS_IMG_DATA: {
@@ -517,8 +513,7 @@ GifDecodeStatus gif_load_frame(CGifContext* context, int32_t frame_num) {
   GifImage* gif_image_ptr = context->m_Images[frame_num].get();
   uint32_t gif_img_row_bytes = gif_image_ptr->m_ImageInfo.width;
   if (gif_img_row_bytes == 0) {
-    context->ThrowError("Error Invalid Number of Row Bytes");
-    NOTREACHED();
+    context->AddError("Error Invalid Number of Row Bytes");
     return GifDecodeStatus::Error;
   }
   if (context->decode_status == GIF_D_STATUS_TAIL) {
@@ -541,8 +536,7 @@ GifDecodeStatus gif_load_frame(CGifContext* context, int32_t frame_num) {
           (bool)((GifLF*)&gif_image_ptr->m_ImageInfo.local_flag)->interlace);
       if (!bRes) {
         gif_image_ptr->m_ImageRowBuf.clear();
-        context->ThrowError("Error Read Record Position Data");
-        NOTREACHED();
+        context->AddError("Error Read Record Position Data");
         return GifDecodeStatus::Error;
       }
     } else {
@@ -560,15 +554,13 @@ GifDecodeStatus gif_load_frame(CGifContext* context, int32_t frame_num) {
           (bool)((GifLF*)&gif_image_ptr->m_ImageInfo.local_flag)->interlace);
       if (!bRes) {
         gif_image_ptr->m_ImageRowBuf.clear();
-        context->ThrowError("Error Read Record Position Data");
-        NOTREACHED();
+        context->AddError("Error Read Record Position Data");
         return GifDecodeStatus::Error;
       }
     }
     if (gif_image_ptr->image_code_size >= 13) {
       gif_image_ptr->m_ImageRowBuf.clear();
-      context->ThrowError("Error Invalid Code Size");
-      NOTREACHED();
+      context->AddError("Error Invalid Code Size");
       return GifDecodeStatus::Error;
     }
     if (!context->m_ImgDecoder.get())
@@ -665,8 +657,7 @@ GifDecodeStatus gif_load_frame(CGifContext* context, int32_t frame_num) {
     }
     gif_save_decoding_status(context, GIF_D_STATUS_TAIL);
   }
-  context->ThrowError("Decode Image Data Error");
-  NOTREACHED();
+  context->AddError("Decode Image Data Error");
   return GifDecodeStatus::Error;
 }