1 // Copyright 2014 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6 
7 #include <setjmp.h>
8 
9 #include "core/include/fxcrt/fx_basic.h"
10 
11 extern FX_WORD _GetWord_LSBFirst(uint8_t* p);
12 extern void _SetWord_LSBFirst(uint8_t* p, FX_WORD v);
13 extern void _BpcConvert(const uint8_t* src_buf,
14                         FX_DWORD src_len,
15                         int32_t src_bpc,
16                         int32_t dst_bpc,
17                         uint8_t*& dst_buf,
18                         FX_DWORD& dst_len);
19 #define GIF_SUPPORT_COMMENT_EXTENSION
20 #define GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
21 #define GIF_SUPPORT_PLAIN_TEXT_EXTENSION
22 #define GIF_SIGNATURE "GIF"
23 #define GIF_SIG_EXTENSION 0x21
24 #define GIF_SIG_IMAGE 0x2C
25 #define GIF_SIG_TRAILER 0x3B
26 #define GIF_BLOCK_GCE 0xF9
27 #define GIF_BLOCK_PTE 0x01
28 #define GIF_BLOCK_CE 0xFE
29 #define GIF_BLOCK_AE 0xFF
30 #define GIF_BLOCK_TERMINAL 0x00
31 #define GIF_MAX_LZW_CODE 4096
32 #define GIF_DATA_BLOCK 255
33 #define GIF_MAX_ERROR_SIZE 256
34 #define GIF_D_STATUS_SIG 0x01
35 #define GIF_D_STATUS_TAIL 0x02
36 #define GIF_D_STATUS_EXT 0x03
37 #define GIF_D_STATUS_EXT_AE 0x04
38 #define GIF_D_STATUS_EXT_CE 0x05
39 #define GIF_D_STATUS_EXT_GCE 0x06
40 #define GIF_D_STATUS_EXT_PTE 0x07
41 #define GIF_D_STATUS_EXT_UNE 0x08
42 #define GIF_D_STATUS_IMG_INFO 0x09
43 #define GIF_D_STATUS_IMG_DATA 0x0A
44 #pragma pack(1)
45 typedef struct tagGifGF {
46   uint8_t pal_bits : 3;
47   uint8_t sort_flag : 1;
48   uint8_t color_resolution : 3;
49   uint8_t global_pal : 1;
50 } GifGF;
51 typedef struct tagGifLF {
52   uint8_t pal_bits : 3;
53   uint8_t reserved : 2;
54   uint8_t sort_flag : 1;
55   uint8_t interlace : 1;
56   uint8_t local_pal : 1;
57 } GifLF;
58 typedef struct tagGifHeader {
59   char signature[3];
60   char version[3];
61 } GifHeader;
62 typedef struct tagGifLSD {
63   FX_WORD width;
64   FX_WORD height;
65   uint8_t global_flag;
66   uint8_t bc_index;
67   uint8_t pixel_aspect;
68 } GifLSD;
69 typedef struct tagGifImageInfo {
70   FX_WORD left;
71   FX_WORD top;
72   FX_WORD width;
73   FX_WORD height;
74 
75   uint8_t local_flag;
76 } GifImageInfo;
77 typedef struct tagGifCEF {
78   uint8_t transparency : 1;
79   uint8_t user_input : 1;
80   uint8_t disposal_method : 3;
81   uint8_t reserved : 3;
82 } GifCEF;
83 typedef struct tagGifGCE {
84   uint8_t block_size;
85   uint8_t gce_flag;
86   FX_WORD delay_time;
87   uint8_t trans_index;
88 } GifGCE;
89 typedef struct tagGifPTE {
90   uint8_t block_size;
91   FX_WORD grid_left;
92   FX_WORD grid_top;
93   FX_WORD grid_width;
94   FX_WORD grid_height;
95 
96   uint8_t char_width;
97   uint8_t char_height;
98 
99   uint8_t fc_index;
100   uint8_t bc_index;
101 } GifPTE;
102 typedef struct tagGifAE {
103   uint8_t block_size;
104   uint8_t app_identify[8];
105   uint8_t app_authentication[3];
106 } GifAE;
107 typedef struct tagGifPalette { uint8_t r, g, b; } GifPalette;
108 #pragma pack()
109 typedef struct tagGifImage {
110   GifGCE* image_gce_ptr;
111   GifPalette* local_pal_ptr;
112   GifImageInfo* image_info_ptr;
113   uint8_t image_code_size;
114   FX_DWORD image_data_pos;
115   uint8_t* image_row_buf;
116   int32_t image_row_num;
117 } GifImage;
118 typedef struct tagGifPlainText {
119   GifGCE* gce_ptr;
120   GifPTE* pte_ptr;
121   CFX_ByteString* string_ptr;
122 } GifPlainText;
123 class CGifLZWDecoder {
124  public:
125   struct tag_Table {
126     FX_WORD prefix;
127     uint8_t suffix;
128   };
129   CGifLZWDecoder(FX_CHAR* error_ptr = NULL) { err_msg_ptr = error_ptr; }
130   void InitTable(uint8_t code_len);
131 
132   int32_t Decode(uint8_t* des_buf, FX_DWORD& des_size);
133 
134   void Input(uint8_t* src_buf, FX_DWORD src_size);
135   FX_DWORD GetAvailInput();
136 
137  private:
138   void ClearTable();
139   void AddCode(FX_WORD prefix_code, uint8_t append_char);
140   void DecodeString(FX_WORD code);
141   uint8_t code_size;
142   uint8_t code_size_cur;
143   FX_WORD code_clear;
144   FX_WORD code_end;
145   FX_WORD code_next;
146   uint8_t code_first;
147   uint8_t stack[GIF_MAX_LZW_CODE];
148   FX_WORD stack_size;
149   tag_Table code_table[GIF_MAX_LZW_CODE];
150   FX_WORD code_old;
151 
152   uint8_t* next_in;
153   FX_DWORD avail_in;
154 
155   uint8_t bits_left;
156   FX_DWORD code_store;
157 
158   FX_CHAR* err_msg_ptr;
159 };
160 class CGifLZWEncoder {
161  public:
162   struct tag_Table {
163     FX_WORD prefix;
164     uint8_t suffix;
165   };
166   CGifLZWEncoder();
167   ~CGifLZWEncoder();
168   void Start(uint8_t code_len,
169              const uint8_t* src_buf,
170              uint8_t*& dst_buf,
171              FX_DWORD& offset);
172   FX_BOOL Encode(const uint8_t* src_buf,
173                  FX_DWORD src_len,
174                  uint8_t*& dst_buf,
175                  FX_DWORD& dst_len,
176                  FX_DWORD& offset);
177   void Finish(uint8_t*& dst_buf, FX_DWORD& dst_len, FX_DWORD& offset);
178 
179  private:
180   void ClearTable();
181   FX_BOOL LookUpInTable(const uint8_t* buf,
182                         FX_DWORD& offset,
183                         uint8_t& bit_offset);
184   void EncodeString(FX_DWORD index,
185                     uint8_t*& dst_buf,
186                     FX_DWORD& dst_len,
187                     FX_DWORD& offset);
188   void WriteBlock(uint8_t*& dst_buf, FX_DWORD& dst_len, FX_DWORD& offset);
189   jmp_buf jmp;
190   FX_DWORD src_offset;
191   uint8_t src_bit_offset;
192   uint8_t src_bit_cut;
193   FX_DWORD src_bit_num;
194   uint8_t code_size;
195   FX_WORD code_clear;
196   FX_WORD code_end;
197   FX_WORD index_num;
198   uint8_t bit_offset;
199   uint8_t index_bit_cur;
200   uint8_t index_buf[GIF_DATA_BLOCK];
201   uint8_t index_buf_len;
202   tag_Table code_table[GIF_MAX_LZW_CODE];
203   FX_WORD table_cur;
204 };
205 typedef struct tag_gif_decompress_struct gif_decompress_struct;
206 typedef gif_decompress_struct* gif_decompress_struct_p;
207 typedef gif_decompress_struct_p* gif_decompress_struct_pp;
208 static int32_t s_gif_interlace_step[4] = {8, 8, 4, 2};
209 struct tag_gif_decompress_struct {
210   jmp_buf jmpbuf;
211   FX_CHAR* err_ptr;
212   void (*_gif_error_fn)(gif_decompress_struct_p gif_ptr,
213                         const FX_CHAR* err_msg);
214   void* context_ptr;
215   int width;
216   int height;
217   GifPalette* global_pal_ptr;
218   int32_t global_pal_num;
219   uint8_t global_sort_flag;
220   uint8_t global_color_resolution;
221 
222   uint8_t bc_index;
223   uint8_t pixel_aspect;
224   CGifLZWDecoder* img_decoder_ptr;
225   FX_DWORD img_row_offset;
226   FX_DWORD img_row_avail_size;
227   uint8_t img_pass_num;
228   CFX_ArrayTemplate<GifImage*>* img_ptr_arr_ptr;
229   uint8_t* (*_gif_ask_buf_for_pal_fn)(gif_decompress_struct_p gif_ptr,
230                                       int32_t pal_size);
231   uint8_t* next_in;
232   FX_DWORD avail_in;
233   int32_t decode_status;
234   FX_DWORD skip_size;
235   void (*_gif_record_current_position_fn)(gif_decompress_struct_p gif_ptr,
236                                           FX_DWORD* cur_pos_ptr);
237   void (*_gif_get_row_fn)(gif_decompress_struct_p gif_ptr,
238                           int32_t row_num,
239                           uint8_t* row_buf);
240   FX_BOOL			(*_gif_get_record_position_fn)(gif_decompress_struct_p gif_ptr, FX_DWORD cur_pos,
241             int32_t left, int32_t top, int32_t width, int32_t height,
242             int32_t pal_num, void* pal_ptr,
243             int32_t delay_time, FX_BOOL user_input,
244             int32_t trans_index, int32_t disposal_method, FX_BOOL interlace);
245 #ifdef GIF_SUPPORT_APPLICATION_EXTENSION
246   uint8_t app_identify[8];
247   uint8_t app_authentication[3];
248   FX_DWORD app_data_size;
249   uint8_t* app_data;
250 #endif
251 #ifdef GIF_SUPPORT_COMMENT_EXTENSION
252   CFX_ByteString* cmt_data_ptr;
253 #endif
254 #ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
255   GifGCE* gce_ptr;
256 #endif
257 #ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
258   CFX_ArrayTemplate<GifPlainText*>* pt_ptr_arr_ptr;
259 #endif
260 };
261 typedef struct tag_gif_compress_struct gif_compress_struct;
262 typedef gif_compress_struct* gif_compress_struct_p;
263 typedef gif_compress_struct_p* gif_compress_struct_pp;
264 struct tag_gif_compress_struct {
265   const uint8_t* src_buf;
266   FX_DWORD src_pitch;
267   FX_DWORD src_width;
268   FX_DWORD src_row;
269   FX_DWORD cur_offset;
270   FX_DWORD frames;
271   GifHeader* header_ptr;
272   GifLSD* lsd_ptr;
273   GifPalette* global_pal;
274   FX_WORD gpal_num;
275   GifPalette* local_pal;
276   FX_WORD lpal_num;
277   GifImageInfo* image_info_ptr;
278   CGifLZWEncoder* img_encoder_ptr;
279 #ifdef GIF_SUPPORT_APPLICATION_EXTENSION
280   uint8_t app_identify[8];
281   uint8_t app_authentication[3];
282   FX_DWORD app_data_size;
283   uint8_t* app_data;
284 #endif
285 
286 #ifdef GIF_SUPPORT_COMMENT_EXTENSION
287   uint8_t* cmt_data_ptr;
288   FX_DWORD cmt_data_len;
289 #endif
290 
291 #ifdef GIF_SUPPORT_GRAPHIC_CONTROL_EXTENSION
292   GifGCE* gce_ptr;
293 #endif
294 
295 #ifdef GIF_SUPPORT_PLAIN_TEXT_EXTENSION
296   GifPTE* pte_ptr;
297   const uint8_t* pte_data_ptr;
298   FX_DWORD pte_data_len;
299 #endif
300 };
301 void _gif_error(gif_decompress_struct_p gif_ptr, const FX_CHAR* err_msg);
302 void _gif_warn(gif_decompress_struct_p gif_ptr, const FX_CHAR* err_msg);
303 gif_decompress_struct_p _gif_create_decompress();
304 void _gif_destroy_decompress(gif_decompress_struct_pp gif_ptr_ptr);
305 gif_compress_struct_p _gif_create_compress();
306 void _gif_destroy_compress(gif_compress_struct_pp gif_ptr_ptr);
307 int32_t _gif_read_header(gif_decompress_struct_p gif_ptr);
308 int32_t _gif_get_frame(gif_decompress_struct_p gif_ptr);
309 int32_t _gif_get_frame_num(gif_decompress_struct_p gif_ptr);
310 int32_t _gif_decode_extension(gif_decompress_struct_p gif_ptr);
311 int32_t _gif_decode_image_info(gif_decompress_struct_p gif_ptr);
312 void _gif_takeover_gce_ptr(gif_decompress_struct_p gif_ptr,
313                            GifGCE** gce_ptr_ptr);
314 int32_t _gif_load_frame(gif_decompress_struct_p gif_ptr, int32_t frame_num);
315 uint8_t* _gif_read_data(gif_decompress_struct_p gif_ptr,
316                         uint8_t** des_buf_pp,
317                         FX_DWORD data_size);
318 void _gif_save_decoding_status(gif_decompress_struct_p gif_ptr, int32_t status);
319 void _gif_input_buffer(gif_decompress_struct_p gif_ptr,
320                        uint8_t* src_buf,
321                        FX_DWORD src_size);
322 FX_DWORD _gif_get_avail_input(gif_decompress_struct_p gif_ptr,
323                               uint8_t** avial_buf_ptr);
324 void interlace_buf(const uint8_t* buf, FX_DWORD width, FX_DWORD height);
325 FX_BOOL _gif_encode(gif_compress_struct_p gif_ptr,
326                     uint8_t*& dst_buf,
327                     FX_DWORD& dst_len);
328 #define GIF_PTR_NOT_NULL(ptr, gif_ptr)    \
329   if (ptr == NULL) {                      \
330     _gif_error(gif_ptr, "Out Of Memory"); \
331     return 0;                             \
332   }
333