Tidy cfx_gif.h.chromium/3415chromium/3414chromium/3413

Use C++ style struct syntax (file already has other C++ features).

Assert that things have packed as intended since they map to
known layouts. Order these asserts in the same order as .h file.

Change-Id: I0a006c4b5789fb544783f488d5b4e609e32c7ec1
Reviewed-on: https://pdfium-review.googlesource.com/31654
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

2 files changed, 38 insertions, 26 deletions

diff --git a/core/fxcodec/gif/cfx_gif.cpp b/core/fxcodec/gif/cfx_gif.cpp
index e87b9df975..18d474ba9a 100644
--- a/core/fxcodec/gif/cfx_gif.cpp
+++ b/core/fxcodec/gif/cfx_gif.cpp
@@ -9,15 +9,23 @@
 const char kGifSignature87[] = "GIF87a";
 const char kGifSignature89[] = "GIF89a";
 
+static_assert(sizeof(CFX_GifGlobalFlags) == 1,
+              "CFX_GifGlobalFlags should have a size of 1");
+static_assert(sizeof(CFX_GifLocalFlags) == 1,
+              "CFX_GifLocalFlags should have a size of 1");
+static_assert(sizeof(CFX_GifHeader) == 6,
+              "CFX_GifHeader should have a size of 6");
+static_assert(sizeof(CFX_GifLocalScreenDescriptor) == 7,
+              "CFX_GifLocalScreenDescriptor should have a size of 7");
 static_assert(sizeof(CFX_CFX_GifImageInfo) == 9,
               "CFX_CFX_GifImageInfo should have a size of 9");
-static_assert(sizeof(CFX_GifPalette) == 3,
-              "CFX_GifPalette should have a size of 3");
+static_assert(sizeof(CFX_GifControlExtensionFlags) == 1,
+              "CFX_GifControlExtensionFlags should have a size of 1");
 static_assert(sizeof(CFX_GifPlainTextExtension) == 13,
               "CFX_GifPlainTextExtension should have a size of 13");
 static_assert(sizeof(CFX_GifGraphicControlExtension) == 5,
               "CFX_GifGraphicControlExtension should have a size of 5");
-static_assert(sizeof(CFX_GifHeader) == 6,
-              "CFX_GifHeader should have a size of 6");
-static_assert(sizeof(CFX_GifLocalScreenDescriptor) == 7,
-              "CFX_GifLocalScreenDescriptor should have a size of 7");
+static_assert(sizeof(GifApplicationExtension) == 12,
+              "GifApplicationExtension should have a size of 12");
+static_assert(sizeof(CFX_GifPalette) == 3,
+              "CFX_GifPalette should have a size of 3");
diff --git a/core/fxcodec/gif/cfx_gif.h b/core/fxcodec/gif/cfx_gif.h
index 5abe1ad33f..bba2d9c911 100644
--- a/core/fxcodec/gif/cfx_gif.h
+++ b/core/fxcodec/gif/cfx_gif.h
@@ -36,74 +36,78 @@ extern const char kGifSignature89[];
 #define GIF_D_STATUS_IMG_DATA 0x0A
 
 #pragma pack(1)
-typedef struct {
+struct CFX_GifGlobalFlags {
   uint8_t pal_bits : 3;
   uint8_t sort_flag : 1;
   uint8_t color_resolution : 3;
   uint8_t global_pal : 1;
-} CFX_GifGlobalFlags;
+};
 
-typedef struct {
+struct CFX_GifLocalFlags {
   uint8_t pal_bits : 3;
   uint8_t reserved : 2;
   uint8_t sort_flag : 1;
   uint8_t interlace : 1;
   uint8_t local_pal : 1;
-} CFX_GifLocalFlags;
+};
 
-typedef struct { char signature[6]; } CFX_GifHeader;
+struct CFX_GifHeader {
+  char signature[6];
+};
 
-typedef struct {
+struct CFX_GifLocalScreenDescriptor {
   uint16_t width;
   uint16_t height;
   CFX_GifGlobalFlags global_flags;
   uint8_t bc_index;
   uint8_t pixel_aspect;
-} CFX_GifLocalScreenDescriptor;
+};
 
-typedef struct {
+struct CFX_CFX_GifImageInfo {
   uint16_t left;
   uint16_t top;
   uint16_t width;
   uint16_t height;
   CFX_GifLocalFlags local_flags;
-} CFX_CFX_GifImageInfo;
+};
 
-typedef struct {
+struct CFX_GifControlExtensionFlags {
   uint8_t transparency : 1;
   uint8_t user_input : 1;
   uint8_t disposal_method : 3;
   uint8_t reserved : 3;
-} CFX_GifControlExtensionFlags;
+};
 
-typedef struct {
+struct CFX_GifGraphicControlExtension {
   uint8_t block_size;
   CFX_GifControlExtensionFlags gce_flags;
   uint16_t delay_time;
   uint8_t trans_index;
-} CFX_GifGraphicControlExtension;
+};
 
-typedef struct {
+struct CFX_GifPlainTextExtension {
   uint8_t block_size;
   uint16_t grid_left;
   uint16_t grid_top;
   uint16_t grid_width;
   uint16_t grid_height;
-
   uint8_t char_width;
   uint8_t char_height;
-
   uint8_t fc_index;
   uint8_t bc_index;
-} CFX_GifPlainTextExtension;
+};
 
-typedef struct {
+struct GifApplicationExtension {
   uint8_t block_size;
   uint8_t app_identify[8];
   uint8_t app_authentication[3];
-} GifApplicationExtension;
+};
 
-typedef struct { uint8_t r, g, b; } CFX_GifPalette;
+struct CFX_GifPalette {
+  uint8_t r;
+  uint8_t g;
+  uint8_t b;
+};
 #pragma pack()
 
 enum class CFX_GifDecodeStatus {