Rename some functions that start with underscore.

Fix misc issues along the way.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1739623002 .
diff --git a/core/src/fxcodec/lgif/fx_gif.cpp b/core/src/fxcodec/lgif/fx_gif.cpp
index ffac891..a4de729 100644
--- a/core/src/fxcodec/lgif/fx_gif.cpp
+++ b/core/src/fxcodec/lgif/fx_gif.cpp
@@ -5,6 +5,9 @@
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "core/src/fxcodec/lgif/fx_gif.h"
+
+#include "core/src/fxcodec/lbmp/fx_bmp.h"
+
 void CGifLZWDecoder::Input(uint8_t* src_buf, FX_DWORD src_size) {
   next_in = src_buf;
   avail_in = src_size;
@@ -141,9 +144,9 @@
   }
   return 0;
 }
-static FX_BOOL _gif_grow_buf(uint8_t*& dst_buf,
-                             FX_DWORD& dst_len,
-                             FX_DWORD size) {
+static FX_BOOL gif_grow_buf(uint8_t*& dst_buf,
+                            FX_DWORD& dst_len,
+                            FX_DWORD size) {
   if (dst_len < size) {
     FX_DWORD len_org = dst_len;
     while (dst_buf && dst_len < size) {
@@ -162,19 +165,19 @@
   }
   return TRUE;
 }
-static inline void _gif_cut_index(uint8_t& val,
-                                  FX_DWORD index,
-                                  uint8_t index_bit,
-                                  uint8_t index_bit_use,
-                                  uint8_t bit_use) {
+static inline void gif_cut_index(uint8_t& val,
+                                 FX_DWORD index,
+                                 uint8_t index_bit,
+                                 uint8_t index_bit_use,
+                                 uint8_t bit_use) {
   FX_DWORD cut = ((1 << (index_bit - index_bit_use)) - 1) << index_bit_use;
   val |= ((index & cut) >> index_bit_use) << bit_use;
 }
-static inline uint8_t _gif_cut_buf(const uint8_t* buf,
-                                   FX_DWORD& offset,
-                                   uint8_t bit_cut,
-                                   uint8_t& bit_offset,
-                                   FX_DWORD& bit_num) {
+static inline uint8_t gif_cut_buf(const uint8_t* buf,
+                                  FX_DWORD& offset,
+                                  uint8_t bit_cut,
+                                  uint8_t& bit_offset,
+                                  FX_DWORD& bit_num) {
   if (bit_cut != 8) {
     FX_WORD index = 0;
     index |= ((1 << bit_cut) - 1) << (7 - bit_offset);
@@ -224,15 +227,15 @@
   src_offset = 0;
   src_bit_offset = 0;
   src_bit_num = 0;
-  code_table[index_num].prefix = _gif_cut_buf(src_buf, src_offset, src_bit_cut,
-                                              src_bit_offset, src_bit_num);
-  code_table[index_num].suffix = _gif_cut_buf(src_buf, src_offset, src_bit_cut,
-                                              src_bit_offset, src_bit_num);
+  code_table[index_num].prefix = gif_cut_buf(src_buf, src_offset, src_bit_cut,
+                                             src_bit_offset, src_bit_num);
+  code_table[index_num].suffix = gif_cut_buf(src_buf, src_offset, src_bit_cut,
+                                             src_bit_offset, src_bit_num);
 }
 void CGifLZWEncoder::WriteBlock(uint8_t*& dst_buf,
                                 FX_DWORD& dst_len,
                                 FX_DWORD& offset) {
-  if (!_gif_grow_buf(dst_buf, dst_len, offset + GIF_DATA_BLOCK + 1)) {
+  if (!gif_grow_buf(dst_buf, dst_len, offset + GIF_DATA_BLOCK + 1)) {
     longjmp(jmp, 1);
   }
   dst_buf[offset++] = index_buf_len;
@@ -250,8 +253,8 @@
   if (index_buf_len == GIF_DATA_BLOCK) {
     WriteBlock(dst_buf, dst_len, offset);
   }
-  _gif_cut_index(index_buf[index_buf_len], index, index_bit_cur, index_bit_use,
-                 bit_offset);
+  gif_cut_index(index_buf[index_buf_len], index, index_bit_cur, index_bit_use,
+                bit_offset);
   if (index_bit_cur <= (8 - bit_offset)) {
     bit_offset += index_bit_cur;
   } else if (index_bit_cur <= (16 - bit_offset)) {
@@ -261,8 +264,8 @@
     if (index_buf_len == GIF_DATA_BLOCK) {
       WriteBlock(dst_buf, dst_len, offset);
     }
-    _gif_cut_index(index_buf[index_buf_len], index, index_bit_cur,
-                   index_bit_use, bit_offset);
+    gif_cut_index(index_buf[index_buf_len], index, index_bit_cur, index_bit_use,
+                  bit_offset);
     bit_offset = index_bit_cur - index_bit_use;
   } else {
     index_bit_use += (8 - bit_offset);
@@ -271,16 +274,16 @@
     if (index_buf_len == GIF_DATA_BLOCK) {
       WriteBlock(dst_buf, dst_len, offset);
     }
-    _gif_cut_index(index_buf[index_buf_len], index, index_bit_cur,
-                   index_bit_use, bit_offset);
+    gif_cut_index(index_buf[index_buf_len], index, index_bit_cur, index_bit_use,
+                  bit_offset);
     index_bit_use += 8;
     bit_offset = 0;
     index_buf_len++;
     if (index_buf_len == GIF_DATA_BLOCK) {
       WriteBlock(dst_buf, dst_len, offset);
     }
-    _gif_cut_index(index_buf[index_buf_len], index, index_bit_cur,
-                   index_bit_use, bit_offset);
+    gif_cut_index(index_buf[index_buf_len], index, index_bit_cur, index_bit_use,
+                  bit_offset);
     bit_offset = index_bit_cur - index_bit_use;
   }
   if (bit_offset == 8) {
@@ -315,11 +318,11 @@
         EncodeString(code_clear, dst_buf, dst_len, offset);
         ClearTable();
         code_table[index_num].prefix = suffix;
-        code_table[index_num].suffix = _gif_cut_buf(
+        code_table[index_num].suffix = gif_cut_buf(
             src_buf, src_offset, src_bit_cut, src_bit_offset, src_bit_num);
       } else {
         code_table[index_num].prefix = code_table[index_num - 1].suffix;
-        code_table[index_num].suffix = _gif_cut_buf(
+        code_table[index_num].suffix = gif_cut_buf(
             src_buf, src_offset, src_bit_cut, src_bit_offset, src_bit_num);
       }
     }
@@ -337,7 +340,7 @@
         code_table[i].suffix == code_table[index_num].suffix) {
       code_table[index_num].prefix = i;
       code_table[index_num].suffix =
-          _gif_cut_buf(buf, offset, src_bit_cut, bit_offset, src_bit_num);
+          gif_cut_buf(buf, offset, src_bit_cut, bit_offset, src_bit_num);
       table_cur = i;
       return TRUE;
     }
@@ -353,7 +356,7 @@
   bit_offset = 0;
   ClearTable();
 }
-gif_decompress_struct_p _gif_create_decompress() {
+gif_decompress_struct_p gif_create_decompress() {
   gif_decompress_struct_p gif_ptr =
       (gif_decompress_struct*)FX_Alloc(uint8_t, sizeof(gif_decompress_struct));
   if (gif_ptr == NULL) {
@@ -362,15 +365,11 @@
   FXSYS_memset(gif_ptr, 0, sizeof(gif_decompress_struct));
   gif_ptr->decode_status = GIF_D_STATUS_SIG;
   gif_ptr->img_ptr_arr_ptr = new CFX_ArrayTemplate<GifImage*>;
-#ifdef GIF_SUPPORT_COMMENT_EXTENSION
   gif_ptr->cmt_data_ptr = new CFX_ByteString;
-#endif
-#ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
   gif_ptr->pt_ptr_arr_ptr = new CFX_ArrayTemplate<GifPlainText*>;
-#endif
   return gif_ptr;
 }
-void _gif_destroy_decompress(gif_decompress_struct_pp gif_ptr_ptr) {
+void gif_destroy_decompress(gif_decompress_struct_pp gif_ptr_ptr) {
   if (gif_ptr_ptr == NULL || *gif_ptr_ptr == NULL) {
     return;
   }
@@ -393,16 +392,8 @@
     gif_ptr->img_ptr_arr_ptr->RemoveAll();
     delete gif_ptr->img_ptr_arr_ptr;
   }
-#ifdef GIF_SUPPORT_APPLICATION_EXTENSION
-  FX_Free(gif_ptr->app_data);
-#endif
-#ifdef GIF_SUPPORT_COMMENT_EXTENSION
   delete gif_ptr->cmt_data_ptr;
-#endif
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
   FX_Free(gif_ptr->gce_ptr);
-#endif
-#ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
   if (gif_ptr->pt_ptr_arr_ptr) {
     int32_t size_pt_arr = gif_ptr->pt_ptr_arr_ptr->GetSize();
     for (int32_t i = 0; i < size_pt_arr; i++) {
@@ -414,10 +405,9 @@
     gif_ptr->pt_ptr_arr_ptr->RemoveAll();
     delete gif_ptr->pt_ptr_arr_ptr;
   }
-#endif
   FX_Free(gif_ptr);
 }
-gif_compress_struct_p _gif_create_compress() {
+gif_compress_struct_p gif_create_compress() {
   gif_compress_struct_p gif_ptr =
       (gif_compress_struct*)FX_Alloc(uint8_t, sizeof(gif_compress_struct));
   if (gif_ptr == NULL) {
@@ -451,11 +441,6 @@
     return NULL;
   }
   FXSYS_memset(gif_ptr->image_info_ptr, 0, sizeof(GifImageInfo));
-#ifdef GIF_SUPPORT_APPLICATION_EXTENSION
-  FXSYS_memcpy(gif_ptr->app_identify, "netscape", 8);
-  FXSYS_memcpy(gif_ptr->app_authentication, "2.0", 3);
-#endif
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
   gif_ptr->gce_ptr = (GifGCE*)FX_Alloc(uint8_t, sizeof(GifGCE));
   if (gif_ptr->gce_ptr == NULL) {
     FX_Free(gif_ptr->image_info_ptr);
@@ -465,8 +450,6 @@
     FX_Free(gif_ptr);
     return NULL;
   }
-#endif
-#ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
   gif_ptr->pte_ptr = (GifPTE*)FX_Alloc(uint8_t, sizeof(GifPTE));
   if (gif_ptr->pte_ptr == NULL) {
     FX_Free(gif_ptr->gce_ptr);
@@ -479,10 +462,9 @@
   }
   FXSYS_memset(gif_ptr->pte_ptr, 0, sizeof(GifPTE));
   gif_ptr->pte_ptr->block_size = 12;
-#endif
   return gif_ptr;
 }
-void _gif_destroy_compress(gif_compress_struct_pp gif_ptr_ptr) {
+void gif_destroy_compress(gif_compress_struct_pp gif_ptr_ptr) {
   if (gif_ptr_ptr == NULL || *gif_ptr_ptr == NULL) {
     return;
   }
@@ -494,44 +476,35 @@
   FX_Free(gif_ptr->image_info_ptr);
   FX_Free(gif_ptr->local_pal);
   delete gif_ptr->img_encoder_ptr;
-#ifdef GIF_SUPPORT_APPLICATION_EXTENSION
-  FX_Free(gif_ptr->app_data);
-#endif
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
   FX_Free(gif_ptr->gce_ptr);
-#endif
-#ifdef GIF_SUPPORT_COMMENT_EXTENSION
   FX_Free(gif_ptr->cmt_data_ptr);
-#endif
-#ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
   FX_Free(gif_ptr->pte_ptr);
-#endif
   FX_Free(gif_ptr);
 }
-void _gif_error(gif_decompress_struct_p gif_ptr, const FX_CHAR* err_msg) {
-  if (gif_ptr && gif_ptr->_gif_error_fn) {
-    gif_ptr->_gif_error_fn(gif_ptr, err_msg);
+void gif_error(gif_decompress_struct_p gif_ptr, const FX_CHAR* err_msg) {
+  if (gif_ptr && gif_ptr->gif_error_fn) {
+    gif_ptr->gif_error_fn(gif_ptr, err_msg);
   }
 }
-void _gif_warn(gif_decompress_struct_p gif_ptr, const FX_CHAR* err_msg) {}
-int32_t _gif_read_header(gif_decompress_struct_p gif_ptr) {
+void gif_warn(gif_decompress_struct_p gif_ptr, const FX_CHAR* err_msg) {}
+int32_t gif_read_header(gif_decompress_struct_p gif_ptr) {
   if (gif_ptr == NULL) {
     return 0;
   }
   FX_DWORD skip_size_org = gif_ptr->skip_size;
   ASSERT(sizeof(GifHeader) == 6);
   GifHeader* gif_header_ptr = NULL;
-  if (_gif_read_data(gif_ptr, (uint8_t**)&gif_header_ptr, 6) == NULL) {
+  if (gif_read_data(gif_ptr, (uint8_t**)&gif_header_ptr, 6) == NULL) {
     return 2;
   }
   if (FXSYS_strncmp(gif_header_ptr->signature, GIF_SIGNATURE, 3) != 0 ||
       gif_header_ptr->version[0] != '8' || gif_header_ptr->version[2] != 'a') {
-    _gif_error(gif_ptr, "Not A Gif Image");
+    gif_error(gif_ptr, "Not A Gif Image");
     return 0;
   }
   ASSERT(sizeof(GifLSD) == 7);
   GifLSD* gif_lsd_ptr = NULL;
-  if (_gif_read_data(gif_ptr, (uint8_t**)&gif_lsd_ptr, 7) == NULL) {
+  if (gif_read_data(gif_ptr, (uint8_t**)&gif_lsd_ptr, 7) == NULL) {
     gif_ptr->skip_size = skip_size_org;
     return 2;
   }
@@ -541,7 +514,7 @@
     ASSERT(sizeof(GifPalette) == 3);
     int32_t global_pal_size = gif_ptr->global_pal_num * 3;
     uint8_t* global_pal_ptr = NULL;
-    if (_gif_read_data(gif_ptr, &global_pal_ptr, global_pal_size) == NULL) {
+    if (gif_read_data(gif_ptr, &global_pal_ptr, global_pal_size) == NULL) {
       gif_ptr->skip_size = skip_size_org;
       return 2;
     }
@@ -552,13 +525,13 @@
     gif_ptr->global_pal_ptr = (GifPalette*)FX_Alloc(uint8_t, global_pal_size);
     FXSYS_memcpy(gif_ptr->global_pal_ptr, global_pal_ptr, global_pal_size);
   }
-  gif_ptr->width = (int)_GetWord_LSBFirst((uint8_t*)&gif_lsd_ptr->width);
-  gif_ptr->height = (int)_GetWord_LSBFirst((uint8_t*)&gif_lsd_ptr->height);
+  gif_ptr->width = (int)GetWord_LSBFirst((uint8_t*)&gif_lsd_ptr->width);
+  gif_ptr->height = (int)GetWord_LSBFirst((uint8_t*)&gif_lsd_ptr->height);
   gif_ptr->bc_index = gif_lsd_ptr->bc_index;
   gif_ptr->pixel_aspect = gif_lsd_ptr->pixel_aspect;
   return 1;
 }
-int32_t _gif_get_frame(gif_decompress_struct_p gif_ptr) {
+int32_t gif_get_frame(gif_decompress_struct_p gif_ptr) {
   if (gif_ptr == NULL) {
     return 0;
   }
@@ -569,69 +542,56 @@
         return 1;
       case GIF_D_STATUS_SIG: {
         uint8_t* sig_ptr = NULL;
-        if (_gif_read_data(gif_ptr, &sig_ptr, 1) == NULL) {
+        if (gif_read_data(gif_ptr, &sig_ptr, 1) == NULL) {
           return 2;
         }
         switch (*sig_ptr) {
           case GIF_SIG_EXTENSION:
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT);
+            gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT);
             continue;
           case GIF_SIG_IMAGE:
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_INFO);
+            gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_INFO);
             continue;
           case GIF_SIG_TRAILER:
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
+            gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
             return 1;
           default:
             if (gif_ptr->avail_in) {
-              _gif_warn(gif_ptr, "The Gif File has non_standard Tag!");
-              _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_SIG);
+              gif_warn(gif_ptr, "The Gif File has non_standard Tag!");
+              gif_save_decoding_status(gif_ptr, GIF_D_STATUS_SIG);
               continue;
             }
-            _gif_warn(gif_ptr, "The Gif File Doesn't have Trailer Tag!");
+            gif_warn(gif_ptr, "The Gif File Doesn't have Trailer Tag!");
             return 1;
         }
       }
       case GIF_D_STATUS_EXT: {
         uint8_t* ext_ptr = NULL;
-        if (_gif_read_data(gif_ptr, &ext_ptr, 1) == NULL) {
+        if (gif_read_data(gif_ptr, &ext_ptr, 1) == NULL) {
           return 2;
         }
         switch (*ext_ptr) {
-#ifdef GIF_SUPPORT_APPLICATION_EXTENSION
-          case GIF_BLOCK_AE:
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT_AE);
-            continue;
-#endif
-#ifdef GIF_SUPPORT_COMMENT_EXTENSION
           case GIF_BLOCK_CE:
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT_CE);
+            gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT_CE);
             continue;
-#endif
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
           case GIF_BLOCK_GCE:
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT_GCE);
+            gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT_GCE);
             continue;
-#endif
-#ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
           case GIF_BLOCK_PTE:
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT_PTE);
+            gif_save_decoding_status(gif_ptr, GIF_D_STATUS_EXT_PTE);
             continue;
-#endif
           default: {
             int32_t status = GIF_D_STATUS_EXT_UNE;
-#ifndef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
             if (*ext_ptr == GIF_BLOCK_PTE) {
               status = GIF_D_STATUS_EXT_PTE;
             }
-#endif
-            _gif_save_decoding_status(gif_ptr, status);
+            gif_save_decoding_status(gif_ptr, status);
             continue;
           }
         }
       }
       case GIF_D_STATUS_IMG_INFO: {
-        ret = _gif_decode_image_info(gif_ptr);
+        ret = gif_decode_image_info(gif_ptr);
         if (ret != 1) {
           return ret;
         }
@@ -641,25 +601,25 @@
         uint8_t* data_size_ptr = NULL;
         uint8_t* data_ptr = NULL;
         FX_DWORD skip_size_org = gif_ptr->skip_size;
-        if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+        if (gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
           return 2;
         }
         while (*data_size_ptr != GIF_BLOCK_TERMINAL) {
-          if (_gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL) {
+          if (gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL) {
             gif_ptr->skip_size = skip_size_org;
             return 2;
           }
-          _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
+          gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
           skip_size_org = gif_ptr->skip_size;
-          if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+          if (gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
             return 2;
           }
         }
-        _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_SIG);
+        gif_save_decoding_status(gif_ptr, GIF_D_STATUS_SIG);
         continue;
       }
       default: {
-        ret = _gif_decode_extension(gif_ptr);
+        ret = gif_decode_extension(gif_ptr);
         if (ret != 1) {
           return ret;
         }
@@ -669,63 +629,29 @@
   }
   return 1;
 }
-void _gif_takeover_gce_ptr(gif_decompress_struct_p gif_ptr,
-                           GifGCE** gce_ptr_ptr) {
+void gif_takeover_gce_ptr(gif_decompress_struct_p gif_ptr,
+                          GifGCE** gce_ptr_ptr) {
   *gce_ptr_ptr = NULL;
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
   if (gif_ptr->gce_ptr && gce_ptr_ptr) {
     *gce_ptr_ptr = gif_ptr->gce_ptr;
     gif_ptr->gce_ptr = NULL;
   }
-#endif
 }
-int32_t _gif_decode_extension(gif_decompress_struct_p gif_ptr) {
+int32_t gif_decode_extension(gif_decompress_struct_p gif_ptr) {
   uint8_t* data_size_ptr = NULL;
   uint8_t* data_ptr = NULL;
   FX_DWORD skip_size_org = gif_ptr->skip_size;
   switch (gif_ptr->decode_status) {
-#ifdef GIF_SUPPORT_APPLICATION_EXTENSION
-    case GIF_D_STATUS_EXT_AE: {
-      ASSERT(sizeof(GifAE) == 12);
-      GifAE* gif_ae_ptr = NULL;
-      if (_gif_read_data(gif_ptr, (uint8_t**)&gif_ae_ptr, 12) == NULL) {
-        return 2;
-      }
-      CFX_ByteString gif_ae_data_str;
-      if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
-        gif_ptr->skip_size = skip_size_org;
-        return 2;
-      }
-      while (*data_size_ptr != GIF_BLOCK_TERMINAL) {
-        uint8_t data_size = *data_size_ptr;
-        if (_gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL ||
-            _gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
-          gif_ptr->skip_size = skip_size_org;
-          return 2;
-        }
-        gif_ae_data_str += CFX_ByteString((const uint8_t*)data_ptr, data_size);
-      }
-      FXSYS_memcpy(gif_ptr->app_identify, gif_ae_ptr->app_identify, 8);
-      FXSYS_memcpy(gif_ptr->app_authentication, gif_ae_ptr->app_authentication,
-                   3);
-      gif_ptr->app_data_size = gif_ae_data_str.GetLength();
-      FX_Free(gif_ptr->app_data);
-      gif_ptr->app_data = FX_Alloc(uint8_t, gif_ptr->app_data_size);
-      FXSYS_memcpy(gif_ptr->app_data, const uint8_t*(gif_ae_data_str),
-                   gif_ptr->app_data_size);
-    } break;
-#endif
-#ifdef GIF_SUPPORT_COMMENT_EXTENSION
     case GIF_D_STATUS_EXT_CE: {
-      if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+      if (gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
         gif_ptr->skip_size = skip_size_org;
         return 2;
       }
       gif_ptr->cmt_data_ptr->Empty();
       while (*data_size_ptr != GIF_BLOCK_TERMINAL) {
         uint8_t data_size = *data_size_ptr;
-        if (_gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL ||
-            _gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+        if (gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL ||
+            gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
           gif_ptr->skip_size = skip_size_org;
           return 2;
         }
@@ -733,33 +659,31 @@
             CFX_ByteString((const FX_CHAR*)data_ptr, data_size);
       }
     } break;
-#endif
-#ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
     case GIF_D_STATUS_EXT_PTE: {
       ASSERT(sizeof(GifPTE) == 13);
       GifPTE* gif_pte_ptr = NULL;
-      if (_gif_read_data(gif_ptr, (uint8_t**)&gif_pte_ptr, 13) == NULL) {
+      if (gif_read_data(gif_ptr, (uint8_t**)&gif_pte_ptr, 13) == NULL) {
         return 2;
       }
       GifPlainText* gif_pt_ptr = FX_Alloc(GifPlainText, 1);
       FXSYS_memset(gif_pt_ptr, 0, sizeof(GifPlainText));
-      _gif_takeover_gce_ptr(gif_ptr, &gif_pt_ptr->gce_ptr);
+      gif_takeover_gce_ptr(gif_ptr, &gif_pt_ptr->gce_ptr);
       gif_pt_ptr->pte_ptr = (GifPTE*)FX_Alloc(uint8_t, sizeof(GifPTE));
       gif_pt_ptr->string_ptr = new CFX_ByteString;
       gif_pt_ptr->pte_ptr->block_size = gif_pte_ptr->block_size;
       gif_pt_ptr->pte_ptr->grid_left =
-          _GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_left);
+          GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_left);
       gif_pt_ptr->pte_ptr->grid_top =
-          _GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_top);
+          GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_top);
       gif_pt_ptr->pte_ptr->grid_width =
-          _GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_width);
+          GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_width);
       gif_pt_ptr->pte_ptr->grid_height =
-          _GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_height);
+          GetWord_LSBFirst((uint8_t*)&gif_pte_ptr->grid_height);
       gif_pt_ptr->pte_ptr->char_width = gif_pte_ptr->char_width;
       gif_pt_ptr->pte_ptr->char_height = gif_pte_ptr->char_height;
       gif_pt_ptr->pte_ptr->fc_index = gif_pte_ptr->fc_index;
       gif_pt_ptr->pte_ptr->bc_index = gif_pte_ptr->bc_index;
-      if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+      if (gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
         gif_ptr->skip_size = skip_size_org;
         if (gif_pt_ptr) {
           FX_Free(gif_pt_ptr->gce_ptr);
@@ -771,8 +695,8 @@
       }
       while (*data_size_ptr != GIF_BLOCK_TERMINAL) {
         uint8_t data_size = *data_size_ptr;
-        if (_gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL ||
-            _gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+        if (gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL ||
+            gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
           gif_ptr->skip_size = skip_size_org;
           if (gif_pt_ptr) {
             FX_Free(gif_pt_ptr->gce_ptr);
@@ -787,12 +711,10 @@
       }
       gif_ptr->pt_ptr_arr_ptr->Add(gif_pt_ptr);
     } break;
-#endif
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
     case GIF_D_STATUS_EXT_GCE: {
       ASSERT(sizeof(GifGCE) == 5);
       GifGCE* gif_gce_ptr = NULL;
-      if (_gif_read_data(gif_ptr, (uint8_t**)&gif_gce_ptr, 6) == NULL) {
+      if (gif_read_data(gif_ptr, (uint8_t**)&gif_gce_ptr, 6) == NULL) {
         return 2;
       }
       if (gif_ptr->gce_ptr == NULL) {
@@ -801,43 +723,38 @@
       gif_ptr->gce_ptr->block_size = gif_gce_ptr->block_size;
       gif_ptr->gce_ptr->gce_flag = gif_gce_ptr->gce_flag;
       gif_ptr->gce_ptr->delay_time =
-          _GetWord_LSBFirst((uint8_t*)&gif_gce_ptr->delay_time);
+          GetWord_LSBFirst((uint8_t*)&gif_gce_ptr->delay_time);
       gif_ptr->gce_ptr->trans_index = gif_gce_ptr->trans_index;
     } break;
-#endif
     default: {
-#ifndef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
       if (gif_ptr->decode_status == GIF_D_STATUS_EXT_PTE) {
         FX_Free(gif_ptr->gce_ptr);
         gif_ptr->gce_ptr = NULL;
       }
-#endif
-#endif
-      if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+      if (gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
         return 2;
       }
       while (*data_size_ptr != GIF_BLOCK_TERMINAL) {
-        if (_gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL ||
-            _gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+        if (gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL ||
+            gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
           gif_ptr->skip_size = skip_size_org;
           return 2;
         }
       }
     }
   }
-  _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_SIG);
+  gif_save_decoding_status(gif_ptr, GIF_D_STATUS_SIG);
   return 1;
 }
-int32_t _gif_decode_image_info(gif_decompress_struct_p gif_ptr) {
+int32_t gif_decode_image_info(gif_decompress_struct_p gif_ptr) {
   if (gif_ptr->width == 0 || gif_ptr->height == 0) {
-    _gif_error(gif_ptr, "No Image Header Info");
+    gif_error(gif_ptr, "No Image Header Info");
     return 0;
   }
   FX_DWORD skip_size_org = gif_ptr->skip_size;
   ASSERT(sizeof(GifImageInfo) == 9);
   GifImageInfo* gif_img_info_ptr = NULL;
-  if (_gif_read_data(gif_ptr, (uint8_t**)&gif_img_info_ptr, 9) == NULL) {
+  if (gif_read_data(gif_ptr, (uint8_t**)&gif_img_info_ptr, 9) == NULL) {
     return 2;
   }
   GifImage* gif_image_ptr = (GifImage*)FX_Alloc(uint8_t, sizeof(GifImage));
@@ -845,13 +762,13 @@
   gif_image_ptr->image_info_ptr =
       (GifImageInfo*)FX_Alloc(uint8_t, sizeof(GifImageInfo));
   gif_image_ptr->image_info_ptr->left =
-      _GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->left);
+      GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->left);
   gif_image_ptr->image_info_ptr->top =
-      _GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->top);
+      GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->top);
   gif_image_ptr->image_info_ptr->width =
-      _GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->width);
+      GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->width);
   gif_image_ptr->image_info_ptr->height =
-      _GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->height);
+      GetWord_LSBFirst((uint8_t*)&gif_img_info_ptr->height);
   gif_image_ptr->image_info_ptr->local_flag = gif_img_info_ptr->local_flag;
   if (gif_image_ptr->image_info_ptr->left +
               gif_image_ptr->image_info_ptr->width >
@@ -862,7 +779,7 @@
     FX_Free(gif_image_ptr->image_info_ptr);
     FX_Free(gif_image_ptr->image_row_buf);
     FX_Free(gif_image_ptr);
-    _gif_error(gif_ptr, "Image Data Out Of LSD, The File May Be Corrupt");
+    gif_error(gif_ptr, "Image Data Out Of LSD, The File May Be Corrupt");
     return 0;
   }
   GifLF* gif_img_info_lf_ptr = (GifLF*)&gif_img_info_ptr->local_flag;
@@ -870,7 +787,7 @@
     ASSERT(sizeof(GifPalette) == 3);
     int32_t loc_pal_size = (2 << gif_img_info_lf_ptr->pal_bits) * 3;
     uint8_t* loc_pal_ptr = NULL;
-    if (_gif_read_data(gif_ptr, &loc_pal_ptr, loc_pal_size) == NULL) {
+    if (gif_read_data(gif_ptr, &loc_pal_ptr, loc_pal_size) == NULL) {
       gif_ptr->skip_size = skip_size_org;
       FX_Free(gif_image_ptr->image_info_ptr);
       FX_Free(gif_image_ptr->image_row_buf);
@@ -878,14 +795,14 @@
       return 2;
     }
     gif_image_ptr->local_pal_ptr =
-        (GifPalette*)gif_ptr->_gif_ask_buf_for_pal_fn(gif_ptr, loc_pal_size);
+        (GifPalette*)gif_ptr->gif_ask_buf_for_pal_fn(gif_ptr, loc_pal_size);
     if (gif_image_ptr->local_pal_ptr) {
       FXSYS_memcpy((uint8_t*)gif_image_ptr->local_pal_ptr, loc_pal_ptr,
                    loc_pal_size);
     }
   }
   uint8_t* code_size_ptr = NULL;
-  if (_gif_read_data(gif_ptr, &code_size_ptr, 1) == NULL) {
+  if (gif_read_data(gif_ptr, &code_size_ptr, 1) == NULL) {
     gif_ptr->skip_size = skip_size_org;
     FX_Free(gif_image_ptr->image_info_ptr);
     FX_Free(gif_image_ptr->local_pal_ptr);
@@ -894,15 +811,15 @@
     return 2;
   }
   gif_image_ptr->image_code_size = *code_size_ptr;
-  gif_ptr->_gif_record_current_position_fn(gif_ptr,
-                                           &gif_image_ptr->image_data_pos);
+  gif_ptr->gif_record_current_position_fn(gif_ptr,
+                                          &gif_image_ptr->image_data_pos);
   gif_image_ptr->image_data_pos += gif_ptr->skip_size;
-  _gif_takeover_gce_ptr(gif_ptr, &gif_image_ptr->image_gce_ptr);
+  gif_takeover_gce_ptr(gif_ptr, &gif_image_ptr->image_gce_ptr);
   gif_ptr->img_ptr_arr_ptr->Add(gif_image_ptr);
-  _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
+  gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
   return 1;
 }
-int32_t _gif_load_frame(gif_decompress_struct_p gif_ptr, int32_t frame_num) {
+int32_t gif_load_frame(gif_decompress_struct_p gif_ptr, int32_t frame_num) {
   if (gif_ptr == NULL || frame_num < 0 ||
       frame_num >= gif_ptr->img_ptr_arr_ptr->GetSize()) {
     return 0;
@@ -926,7 +843,7 @@
             : 0;
     gif_ptr->avail_in = 0;
     if (gif_img_gce_ptr == NULL) {
-      FX_BOOL bRes = gif_ptr->_gif_get_record_position_fn(
+      FX_BOOL bRes = gif_ptr->gif_get_record_position_fn(
           gif_ptr, gif_image_ptr->image_data_pos,
           gif_image_ptr->image_info_ptr->left,
           gif_image_ptr->image_info_ptr->top,
@@ -938,11 +855,11 @@
       if (!bRes) {
         FX_Free(gif_image_ptr->image_row_buf);
         gif_image_ptr->image_row_buf = NULL;
-        _gif_error(gif_ptr, "Error Read Record Position Data");
+        gif_error(gif_ptr, "Error Read Record Position Data");
         return 0;
       }
     } else {
-      FX_BOOL bRes = gif_ptr->_gif_get_record_position_fn(
+      FX_BOOL bRes = gif_ptr->gif_get_record_position_fn(
           gif_ptr, gif_image_ptr->image_data_pos,
           gif_image_ptr->image_info_ptr->left,
           gif_image_ptr->image_info_ptr->top,
@@ -962,7 +879,7 @@
       if (!bRes) {
         FX_Free(gif_image_ptr->image_row_buf);
         gif_image_ptr->image_row_buf = NULL;
-        _gif_error(gif_ptr, "Error Read Record Position Data");
+        gif_error(gif_ptr, "Error Read Record Position Data");
         return 0;
       }
     }
@@ -974,20 +891,20 @@
     gif_ptr->img_row_avail_size = 0;
     gif_ptr->img_pass_num = 0;
     gif_image_ptr->image_row_num = 0;
-    _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
+    gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
   }
   CGifLZWDecoder* img_decoder_ptr = gif_ptr->img_decoder_ptr;
   if (gif_ptr->decode_status == GIF_D_STATUS_IMG_DATA) {
-    if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+    if (gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
       return 2;
     }
     if (*data_size_ptr != GIF_BLOCK_TERMINAL) {
-      if (_gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL) {
+      if (gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL) {
         gif_ptr->skip_size = skip_size_org;
         return 2;
       }
       img_decoder_ptr->Input(data_ptr, *data_size_ptr);
-      _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
+      gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
       gif_ptr->img_row_offset += gif_ptr->img_row_avail_size;
       gif_ptr->img_row_avail_size = gif_img_row_bytes - gif_ptr->img_row_offset;
       int32_t ret = img_decoder_ptr->Decode(
@@ -996,32 +913,32 @@
       if (ret == 0) {
         FX_Free(gif_image_ptr->image_row_buf);
         gif_image_ptr->image_row_buf = NULL;
-        _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
-        _gif_error(gif_ptr, "Decode Image Data Error");
+        gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
+        gif_error(gif_ptr, "Decode Image Data Error");
         return 0;
       }
       while (ret != 0) {
         if (ret == 1) {
-          gif_ptr->_gif_get_row_fn(gif_ptr, gif_image_ptr->image_row_num,
-                                   gif_image_ptr->image_row_buf);
+          gif_ptr->gif_get_row_fn(gif_ptr, gif_image_ptr->image_row_num,
+                                  gif_image_ptr->image_row_buf);
           FX_Free(gif_image_ptr->image_row_buf);
           gif_image_ptr->image_row_buf = NULL;
-          _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
+          gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
           return 1;
         }
         if (ret == 2) {
           ASSERT(img_decoder_ptr->GetAvailInput() == 0);
           skip_size_org = gif_ptr->skip_size;
-          if (_gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
+          if (gif_read_data(gif_ptr, &data_size_ptr, 1) == NULL) {
             return 2;
           }
           if (*data_size_ptr != GIF_BLOCK_TERMINAL) {
-            if (_gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL) {
+            if (gif_read_data(gif_ptr, &data_ptr, *data_size_ptr) == NULL) {
               gif_ptr->skip_size = skip_size_org;
               return 2;
             }
             img_decoder_ptr->Input(data_ptr, *data_size_ptr);
-            _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
+            gif_save_decoding_status(gif_ptr, GIF_D_STATUS_IMG_DATA);
             gif_ptr->img_row_offset += gif_ptr->img_row_avail_size;
             gif_ptr->img_row_avail_size =
                 gif_img_row_bytes - gif_ptr->img_row_offset;
@@ -1032,8 +949,8 @@
         }
         if (ret == 3) {
           if (((GifLF*)&gif_image_ptr->image_info_ptr->local_flag)->interlace) {
-            gif_ptr->_gif_get_row_fn(gif_ptr, gif_image_ptr->image_row_num,
-                                     gif_image_ptr->image_row_buf);
+            gif_ptr->gif_get_row_fn(gif_ptr, gif_image_ptr->image_row_num,
+                                    gif_image_ptr->image_row_buf);
             gif_image_ptr->image_row_num +=
                 s_gif_interlace_step[gif_ptr->img_pass_num];
             if (gif_image_ptr->image_row_num >=
@@ -1043,8 +960,8 @@
                   s_gif_interlace_step[gif_ptr->img_pass_num] / 2;
             }
           } else {
-            gif_ptr->_gif_get_row_fn(gif_ptr, gif_image_ptr->image_row_num++,
-                                     gif_image_ptr->image_row_buf);
+            gif_ptr->gif_get_row_fn(gif_ptr, gif_image_ptr->image_row_num++,
+                                    gif_image_ptr->image_row_buf);
           }
           gif_ptr->img_row_offset = 0;
           gif_ptr->img_row_avail_size = gif_img_row_bytes;
@@ -1055,27 +972,26 @@
         if (ret == 0) {
           FX_Free(gif_image_ptr->image_row_buf);
           gif_image_ptr->image_row_buf = NULL;
-          _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
-          _gif_error(gif_ptr, "Decode Image Data Error");
+          gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
+          gif_error(gif_ptr, "Decode Image Data Error");
           return 0;
         }
       }
     }
-    _gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
+    gif_save_decoding_status(gif_ptr, GIF_D_STATUS_TAIL);
   }
-  _gif_error(gif_ptr, "Decode Image Data Error");
+  gif_error(gif_ptr, "Decode Image Data Error");
   return 0;
 }
-void _gif_save_decoding_status(gif_decompress_struct_p gif_ptr,
-                               int32_t status) {
+void gif_save_decoding_status(gif_decompress_struct_p gif_ptr, int32_t status) {
   gif_ptr->decode_status = status;
   gif_ptr->next_in += gif_ptr->skip_size;
   gif_ptr->avail_in -= gif_ptr->skip_size;
   gif_ptr->skip_size = 0;
 }
-uint8_t* _gif_read_data(gif_decompress_struct_p gif_ptr,
-                        uint8_t** des_buf_pp,
-                        FX_DWORD data_size) {
+uint8_t* gif_read_data(gif_decompress_struct_p gif_ptr,
+                       uint8_t** des_buf_pp,
+                       FX_DWORD data_size) {
   if (gif_ptr == NULL || gif_ptr->avail_in < gif_ptr->skip_size + data_size) {
     return NULL;
   }
@@ -1083,15 +999,15 @@
   gif_ptr->skip_size += data_size;
   return *des_buf_pp;
 }
-void _gif_input_buffer(gif_decompress_struct_p gif_ptr,
-                       uint8_t* src_buf,
-                       FX_DWORD src_size) {
+void gif_input_buffer(gif_decompress_struct_p gif_ptr,
+                      uint8_t* src_buf,
+                      FX_DWORD src_size) {
   gif_ptr->next_in = src_buf;
   gif_ptr->avail_in = src_size;
   gif_ptr->skip_size = 0;
 }
-FX_DWORD _gif_get_avail_input(gif_decompress_struct_p gif_ptr,
-                              uint8_t** avial_buf_ptr) {
+FX_DWORD gif_get_avail_input(gif_decompress_struct_p gif_ptr,
+                             uint8_t** avial_buf_ptr) {
   if (avial_buf_ptr) {
     *avial_buf_ptr = NULL;
     if (gif_ptr->avail_in > 0) {
@@ -1100,12 +1016,12 @@
   }
   return gif_ptr->avail_in;
 }
-int32_t _gif_get_frame_num(gif_decompress_struct_p gif_ptr) {
+int32_t gif_get_frame_num(gif_decompress_struct_p gif_ptr) {
   return gif_ptr->img_ptr_arr_ptr->GetSize();
 }
-static FX_BOOL _gif_write_header(gif_compress_struct_p gif_ptr,
-                                 uint8_t*& dst_buf,
-                                 FX_DWORD& dst_len) {
+static FX_BOOL gif_write_header(gif_compress_struct_p gif_ptr,
+                                uint8_t*& dst_buf,
+                                FX_DWORD& dst_len) {
   if (gif_ptr->cur_offset) {
     return TRUE;
   }
@@ -1117,16 +1033,16 @@
   FXSYS_memset(dst_buf, 0, dst_len);
   FXSYS_memcpy(dst_buf, gif_ptr->header_ptr, sizeof(GifHeader));
   gif_ptr->cur_offset += sizeof(GifHeader);
-  _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->lsd_ptr->width);
+  SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->lsd_ptr->width);
   gif_ptr->cur_offset += 2;
-  _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->lsd_ptr->height);
+  SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->lsd_ptr->height);
   gif_ptr->cur_offset += 2;
   dst_buf[gif_ptr->cur_offset++] = gif_ptr->lsd_ptr->global_flag;
   dst_buf[gif_ptr->cur_offset++] = gif_ptr->lsd_ptr->bc_index;
   dst_buf[gif_ptr->cur_offset++] = gif_ptr->lsd_ptr->pixel_aspect;
   if (gif_ptr->global_pal) {
     FX_WORD size = sizeof(GifPalette) * gif_ptr->gpal_num;
-    if (!_gif_grow_buf(dst_buf, dst_len, gif_ptr->cur_offset + size)) {
+    if (!gif_grow_buf(dst_buf, dst_len, gif_ptr->cur_offset + size)) {
       return FALSE;
     }
     FXSYS_memcpy(&dst_buf[gif_ptr->cur_offset], gif_ptr->global_pal, size);
@@ -1165,11 +1081,11 @@
     }
   }
 }
-static void _gif_write_block_data(const uint8_t* src_buf,
-                                  FX_DWORD src_len,
-                                  uint8_t*& dst_buf,
-                                  FX_DWORD& dst_len,
-                                  FX_DWORD& dst_offset) {
+static void gif_write_block_data(const uint8_t* src_buf,
+                                 FX_DWORD src_len,
+                                 uint8_t*& dst_buf,
+                                 FX_DWORD& dst_len,
+                                 FX_DWORD& dst_offset) {
   FX_DWORD src_offset = 0;
   while (src_len > GIF_DATA_BLOCK) {
     dst_buf[dst_offset++] = GIF_DATA_BLOCK;
@@ -1182,13 +1098,12 @@
   FXSYS_memcpy(&dst_buf[dst_offset], &src_buf[src_offset], src_len);
   dst_offset += src_len;
 }
-static FX_BOOL _gif_write_data(gif_compress_struct_p gif_ptr,
-                               uint8_t*& dst_buf,
-                               FX_DWORD& dst_len) {
-  if (!_gif_grow_buf(dst_buf, dst_len, gif_ptr->cur_offset + GIF_DATA_BLOCK)) {
+static FX_BOOL gif_write_data(gif_compress_struct_p gif_ptr,
+                              uint8_t*& dst_buf,
+                              FX_DWORD& dst_len) {
+  if (!gif_grow_buf(dst_buf, dst_len, gif_ptr->cur_offset + GIF_DATA_BLOCK)) {
     return FALSE;
   }
-#ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
   if (FXSYS_memcmp(gif_ptr->header_ptr->version, "89a", 3) == 0) {
     dst_buf[gif_ptr->cur_offset++] = GIF_SIG_EXTENSION;
     dst_buf[gif_ptr->cur_offset++] = GIF_BLOCK_GCE;
@@ -1197,32 +1112,30 @@
     gif_ptr->gce_ptr->gce_flag = 0;
     dst_buf[gif_ptr->cur_offset++] = gif_ptr->gce_ptr->gce_flag;
     gif_ptr->gce_ptr->delay_time = 10;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->gce_ptr->delay_time);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                     gif_ptr->gce_ptr->delay_time);
     gif_ptr->cur_offset += 2;
     gif_ptr->gce_ptr->trans_index = 0;
     dst_buf[gif_ptr->cur_offset++] = gif_ptr->gce_ptr->trans_index;
     dst_buf[gif_ptr->cur_offset++] = 0;
   }
-#endif
   dst_buf[gif_ptr->cur_offset++] = GIF_SIG_IMAGE;
-  _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                    gif_ptr->image_info_ptr->left);
+  SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                   gif_ptr->image_info_ptr->left);
   gif_ptr->cur_offset += 2;
-  _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                    gif_ptr->image_info_ptr->top);
+  SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->image_info_ptr->top);
   gif_ptr->cur_offset += 2;
-  _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                    gif_ptr->image_info_ptr->width);
+  SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                   gif_ptr->image_info_ptr->width);
   gif_ptr->cur_offset += 2;
-  _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                    gif_ptr->image_info_ptr->height);
+  SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                   gif_ptr->image_info_ptr->height);
   gif_ptr->cur_offset += 2;
   GifLF& lf = (GifLF&)gif_ptr->image_info_ptr->local_flag;
   dst_buf[gif_ptr->cur_offset++] = gif_ptr->image_info_ptr->local_flag;
   if (gif_ptr->local_pal) {
     FX_DWORD pal_size = sizeof(GifPalette) * gif_ptr->lpal_num;
-    if (!_gif_grow_buf(dst_buf, dst_len, pal_size + gif_ptr->cur_offset)) {
+    if (!gif_grow_buf(dst_buf, dst_len, pal_size + gif_ptr->cur_offset)) {
       return FALSE;
     }
     FXSYS_memcpy(&dst_buf[gif_ptr->cur_offset], gif_ptr->local_pal, pal_size);
@@ -1250,75 +1163,52 @@
   }
   gif_ptr->img_encoder_ptr->Finish(dst_buf, dst_len, gif_ptr->cur_offset);
   dst_buf[gif_ptr->cur_offset++] = 0;
-#ifdef GIF_SUPPORT_COMMENT_EXTENSION
   if (FXSYS_memcmp(gif_ptr->header_ptr->version, "89a", 3) == 0 &&
       gif_ptr->cmt_data_ptr) {
     dst_buf[gif_ptr->cur_offset++] = GIF_SIG_EXTENSION;
     dst_buf[gif_ptr->cur_offset++] = GIF_BLOCK_CE;
-    _gif_write_block_data(gif_ptr->cmt_data_ptr, gif_ptr->cmt_data_len, dst_buf,
-                          dst_len, gif_ptr->cur_offset);
+    gif_write_block_data(gif_ptr->cmt_data_ptr, gif_ptr->cmt_data_len, dst_buf,
+                         dst_len, gif_ptr->cur_offset);
     dst_buf[gif_ptr->cur_offset++] = 0;
   }
-#endif
-#ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
   if (FXSYS_memcmp(gif_ptr->header_ptr->version, "89a", 3) == 0 &&
       gif_ptr->pte_data_ptr) {
     dst_buf[gif_ptr->cur_offset++] = GIF_SIG_EXTENSION;
     dst_buf[gif_ptr->cur_offset++] = GIF_BLOCK_PTE;
     dst_buf[gif_ptr->cur_offset++] = gif_ptr->pte_ptr->block_size;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->grid_left);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                     gif_ptr->pte_ptr->grid_left);
     gif_ptr->cur_offset += 2;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->grid_top);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->pte_ptr->grid_top);
     gif_ptr->cur_offset += 2;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->grid_width);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                     gif_ptr->pte_ptr->grid_width);
     gif_ptr->cur_offset += 2;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->grid_height);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                     gif_ptr->pte_ptr->grid_height);
     gif_ptr->cur_offset += 2;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->char_width);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                     gif_ptr->pte_ptr->char_width);
     gif_ptr->cur_offset += 2;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->char_height);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
+                     gif_ptr->pte_ptr->char_height);
     gif_ptr->cur_offset += 2;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->fc_index);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->pte_ptr->fc_index);
     gif_ptr->cur_offset += 2;
-    _SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset,
-                      gif_ptr->pte_ptr->bc_index);
+    SetWord_LSBFirst(dst_buf + gif_ptr->cur_offset, gif_ptr->pte_ptr->bc_index);
     gif_ptr->cur_offset += 2;
-    _gif_write_block_data(gif_ptr->pte_data_ptr, gif_ptr->pte_data_len, dst_buf,
-                          dst_len, gif_ptr->cur_offset);
+    gif_write_block_data(gif_ptr->pte_data_ptr, gif_ptr->pte_data_len, dst_buf,
+                         dst_len, gif_ptr->cur_offset);
     gif_ptr->cur_offset += gif_ptr->pte_data_len;
     dst_buf[gif_ptr->cur_offset++] = 0;
   }
-#endif
-#ifdef GIF_SUPPORT_APPLICATION_EXTENSION
-  if (FXSYS_memcmp(gif_ptr->header_ptr->version, "89a", 3) == 0 &&
-      gif_ptr->app_data) {
-    dst_buf[gif_ptr->cur_offset++] = GIF_SIG_EXTENSION;
-    dst_buf[gif_ptr->cur_offset++] = GIF_BLOCK_AE;
-    dst_buf[gif_ptr->cur_offset++] = 11;
-    FXSYS_memcpy(&dst_buf[gif_ptr->cur_offset], gif_ptr->app_identify, 8);
-    gif_ptr->cur_offset += 8;
-    FXSYS_memcpy(&dst_buf[gif_ptr->cur_offset], gif_ptr->app_authentication, 8);
-    gif_ptr->cur_offset += 3;
-    FXSYS_memcpy(&dst_buf[gif_ptr->cur_offset], gif_ptr->app_data,
-                 gif_ptr->app_data_size);
-    gif_ptr->cur_offset += gif_ptr->app_data_size;
-    dst_buf[gif_ptr->cur_offset++] = 0;
-  }
-#endif
   dst_buf[gif_ptr->cur_offset++] = GIF_SIG_TRAILER;
   return TRUE;
 }
-FX_BOOL _gif_encode(gif_compress_struct_p gif_ptr,
-                    uint8_t*& dst_buf,
-                    FX_DWORD& dst_len) {
-  if (!_gif_write_header(gif_ptr, dst_buf, dst_len)) {
+FX_BOOL gif_encode(gif_compress_struct_p gif_ptr,
+                   uint8_t*& dst_buf,
+                   FX_DWORD& dst_len) {
+  if (!gif_write_header(gif_ptr, dst_buf, dst_len)) {
     return FALSE;
   }
   FX_DWORD cur_offset = gif_ptr->cur_offset;
@@ -1326,7 +1216,7 @@
   if (gif_ptr->frames) {
     gif_ptr->cur_offset--;
   }
-  if (!_gif_write_data(gif_ptr, dst_buf, dst_len)) {
+  if (!gif_write_data(gif_ptr, dst_buf, dst_len)) {
     gif_ptr->cur_offset = cur_offset;
     res = FALSE;
   }