1/*
2 * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
3 * All rights reserved.
4 *
5 * This source code is licensed under both the BSD-style license (found in the
6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found
7 * in the COPYING file in the root directory of this source tree).
8 * You may select, at your option, one of the above-listed licenses.
9 */
10
11#ifndef ZSTD_LEGACY_H
12#define ZSTD_LEGACY_H
13
14#if defined (__cplusplus)
15extern "C" {
16#endif
17
18/* *************************************
19*  Includes
20***************************************/
21#include "mem.h"            /* MEM_STATIC */
22#include "error_private.h"  /* ERROR */
23#include "zstd.h"           /* ZSTD_inBuffer, ZSTD_outBuffer */
24
25#if !defined (ZSTD_LEGACY_SUPPORT) || (ZSTD_LEGACY_SUPPORT == 0)
26#  undef ZSTD_LEGACY_SUPPORT
27#  define ZSTD_LEGACY_SUPPORT 8
28#endif
29
30#if (ZSTD_LEGACY_SUPPORT <= 1)
31#  include "zstd_v01.h"
32#endif
33#if (ZSTD_LEGACY_SUPPORT <= 2)
34#  include "zstd_v02.h"
35#endif
36#if (ZSTD_LEGACY_SUPPORT <= 3)
37#  include "zstd_v03.h"
38#endif
39#if (ZSTD_LEGACY_SUPPORT <= 4)
40#  include "zstd_v04.h"
41#endif
42#if (ZSTD_LEGACY_SUPPORT <= 5)
43#  include "zstd_v05.h"
44#endif
45#if (ZSTD_LEGACY_SUPPORT <= 6)
46#  include "zstd_v06.h"
47#endif
48#if (ZSTD_LEGACY_SUPPORT <= 7)
49#  include "zstd_v07.h"
50#endif
51
52/** ZSTD_isLegacy() :
53    @return : > 0 if supported by legacy decoder. 0 otherwise.
54              return value is the version.
55*/
56MEM_STATIC unsigned ZSTD_isLegacy(const void* src, size_t srcSize)
57{
58    U32 magicNumberLE;
59    if (srcSize<4) return 0;
60    magicNumberLE = MEM_readLE32(src);
61    switch(magicNumberLE)
62    {
63#if (ZSTD_LEGACY_SUPPORT <= 1)
64        case ZSTDv01_magicNumberLE:return 1;
65#endif
66#if (ZSTD_LEGACY_SUPPORT <= 2)
67        case ZSTDv02_magicNumber : return 2;
68#endif
69#if (ZSTD_LEGACY_SUPPORT <= 3)
70        case ZSTDv03_magicNumber : return 3;
71#endif
72#if (ZSTD_LEGACY_SUPPORT <= 4)
73        case ZSTDv04_magicNumber : return 4;
74#endif
75#if (ZSTD_LEGACY_SUPPORT <= 5)
76        case ZSTDv05_MAGICNUMBER : return 5;
77#endif
78#if (ZSTD_LEGACY_SUPPORT <= 6)
79        case ZSTDv06_MAGICNUMBER : return 6;
80#endif
81#if (ZSTD_LEGACY_SUPPORT <= 7)
82        case ZSTDv07_MAGICNUMBER : return 7;
83#endif
84        default : return 0;
85    }
86}
87
88
89MEM_STATIC unsigned long long ZSTD_getDecompressedSize_legacy(const void* src, size_t srcSize)
90{
91    U32 const version = ZSTD_isLegacy(src, srcSize);
92    if (version < 5) return 0;  /* no decompressed size in frame header, or not a legacy format */
93#if (ZSTD_LEGACY_SUPPORT <= 5)
94    if (version==5) {
95        ZSTDv05_parameters fParams;
96        size_t const frResult = ZSTDv05_getFrameParams(&fParams, src, srcSize);
97        if (frResult != 0) return 0;
98        return fParams.srcSize;
99    }
100#endif
101#if (ZSTD_LEGACY_SUPPORT <= 6)
102    if (version==6) {
103        ZSTDv06_frameParams fParams;
104        size_t const frResult = ZSTDv06_getFrameParams(&fParams, src, srcSize);
105        if (frResult != 0) return 0;
106        return fParams.frameContentSize;
107    }
108#endif
109#if (ZSTD_LEGACY_SUPPORT <= 7)
110    if (version==7) {
111        ZSTDv07_frameParams fParams;
112        size_t const frResult = ZSTDv07_getFrameParams(&fParams, src, srcSize);
113        if (frResult != 0) return 0;
114        return fParams.frameContentSize;
115    }
116#endif
117    return 0;   /* should not be possible */
118}
119
120
121MEM_STATIC size_t ZSTD_decompressLegacy(
122                     void* dst, size_t dstCapacity,
123               const void* src, size_t compressedSize,
124               const void* dict,size_t dictSize)
125{
126    U32 const version = ZSTD_isLegacy(src, compressedSize);
127    (void)dst; (void)dstCapacity; (void)dict; (void)dictSize;  /* unused when ZSTD_LEGACY_SUPPORT >= 8 */
128    switch(version)
129    {
130#if (ZSTD_LEGACY_SUPPORT <= 1)
131        case 1 :
132            return ZSTDv01_decompress(dst, dstCapacity, src, compressedSize);
133#endif
134#if (ZSTD_LEGACY_SUPPORT <= 2)
135        case 2 :
136            return ZSTDv02_decompress(dst, dstCapacity, src, compressedSize);
137#endif
138#if (ZSTD_LEGACY_SUPPORT <= 3)
139        case 3 :
140            return ZSTDv03_decompress(dst, dstCapacity, src, compressedSize);
141#endif
142#if (ZSTD_LEGACY_SUPPORT <= 4)
143        case 4 :
144            return ZSTDv04_decompress(dst, dstCapacity, src, compressedSize);
145#endif
146#if (ZSTD_LEGACY_SUPPORT <= 5)
147        case 5 :
148            {   size_t result;
149                ZSTDv05_DCtx* const zd = ZSTDv05_createDCtx();
150                if (zd==NULL) return ERROR(memory_allocation);
151                result = ZSTDv05_decompress_usingDict(zd, dst, dstCapacity, src, compressedSize, dict, dictSize);
152                ZSTDv05_freeDCtx(zd);
153                return result;
154            }
155#endif
156#if (ZSTD_LEGACY_SUPPORT <= 6)
157        case 6 :
158            {   size_t result;
159                ZSTDv06_DCtx* const zd = ZSTDv06_createDCtx();
160                if (zd==NULL) return ERROR(memory_allocation);
161                result = ZSTDv06_decompress_usingDict(zd, dst, dstCapacity, src, compressedSize, dict, dictSize);
162                ZSTDv06_freeDCtx(zd);
163                return result;
164            }
165#endif
166#if (ZSTD_LEGACY_SUPPORT <= 7)
167        case 7 :
168            {   size_t result;
169                ZSTDv07_DCtx* const zd = ZSTDv07_createDCtx();
170                if (zd==NULL) return ERROR(memory_allocation);
171                result = ZSTDv07_decompress_usingDict(zd, dst, dstCapacity, src, compressedSize, dict, dictSize);
172                ZSTDv07_freeDCtx(zd);
173                return result;
174            }
175#endif
176        default :
177            return ERROR(prefix_unknown);
178    }
179}
180
181MEM_STATIC size_t ZSTD_findFrameCompressedSizeLegacy(const void *src,
182                                             size_t compressedSize)
183{
184    U32 const version = ZSTD_isLegacy(src, compressedSize);
185    switch(version)
186    {
187#if (ZSTD_LEGACY_SUPPORT <= 1)
188        case 1 :
189            return ZSTDv01_findFrameCompressedSize(src, compressedSize);
190#endif
191#if (ZSTD_LEGACY_SUPPORT <= 2)
192        case 2 :
193            return ZSTDv02_findFrameCompressedSize(src, compressedSize);
194#endif
195#if (ZSTD_LEGACY_SUPPORT <= 3)
196        case 3 :
197            return ZSTDv03_findFrameCompressedSize(src, compressedSize);
198#endif
199#if (ZSTD_LEGACY_SUPPORT <= 4)
200        case 4 :
201            return ZSTDv04_findFrameCompressedSize(src, compressedSize);
202#endif
203#if (ZSTD_LEGACY_SUPPORT <= 5)
204        case 5 :
205            return ZSTDv05_findFrameCompressedSize(src, compressedSize);
206#endif
207#if (ZSTD_LEGACY_SUPPORT <= 6)
208        case 6 :
209            return ZSTDv06_findFrameCompressedSize(src, compressedSize);
210#endif
211#if (ZSTD_LEGACY_SUPPORT <= 7)
212        case 7 :
213            return ZSTDv07_findFrameCompressedSize(src, compressedSize);
214#endif
215        default :
216            return ERROR(prefix_unknown);
217    }
218}
219
220MEM_STATIC size_t ZSTD_freeLegacyStreamContext(void* legacyContext, U32 version)
221{
222    switch(version)
223    {
224        default :
225        case 1 :
226        case 2 :
227        case 3 :
228            (void)legacyContext;
229            return ERROR(version_unsupported);
230#if (ZSTD_LEGACY_SUPPORT <= 4)
231        case 4 : return ZBUFFv04_freeDCtx((ZBUFFv04_DCtx*)legacyContext);
232#endif
233#if (ZSTD_LEGACY_SUPPORT <= 5)
234        case 5 : return ZBUFFv05_freeDCtx((ZBUFFv05_DCtx*)legacyContext);
235#endif
236#if (ZSTD_LEGACY_SUPPORT <= 6)
237        case 6 : return ZBUFFv06_freeDCtx((ZBUFFv06_DCtx*)legacyContext);
238#endif
239#if (ZSTD_LEGACY_SUPPORT <= 7)
240        case 7 : return ZBUFFv07_freeDCtx((ZBUFFv07_DCtx*)legacyContext);
241#endif
242    }
243}
244
245
246MEM_STATIC size_t ZSTD_initLegacyStream(void** legacyContext, U32 prevVersion, U32 newVersion,
247                                        const void* dict, size_t dictSize)
248{
249    DEBUGLOG(5, "ZSTD_initLegacyStream for v0.%u", newVersion);
250    if (prevVersion != newVersion) ZSTD_freeLegacyStreamContext(*legacyContext, prevVersion);
251    switch(newVersion)
252    {
253        default :
254        case 1 :
255        case 2 :
256        case 3 :
257            (void)dict; (void)dictSize;
258            return 0;
259#if (ZSTD_LEGACY_SUPPORT <= 4)
260        case 4 :
261        {
262            ZBUFFv04_DCtx* dctx = (prevVersion != newVersion) ? ZBUFFv04_createDCtx() : (ZBUFFv04_DCtx*)*legacyContext;
263            if (dctx==NULL) return ERROR(memory_allocation);
264            ZBUFFv04_decompressInit(dctx);
265            ZBUFFv04_decompressWithDictionary(dctx, dict, dictSize);
266            *legacyContext = dctx;
267            return 0;
268        }
269#endif
270#if (ZSTD_LEGACY_SUPPORT <= 5)
271        case 5 :
272        {
273            ZBUFFv05_DCtx* dctx = (prevVersion != newVersion) ? ZBUFFv05_createDCtx() : (ZBUFFv05_DCtx*)*legacyContext;
274            if (dctx==NULL) return ERROR(memory_allocation);
275            ZBUFFv05_decompressInitDictionary(dctx, dict, dictSize);
276            *legacyContext = dctx;
277            return 0;
278        }
279#endif
280#if (ZSTD_LEGACY_SUPPORT <= 6)
281        case 6 :
282        {
283            ZBUFFv06_DCtx* dctx = (prevVersion != newVersion) ? ZBUFFv06_createDCtx() : (ZBUFFv06_DCtx*)*legacyContext;
284            if (dctx==NULL) return ERROR(memory_allocation);
285            ZBUFFv06_decompressInitDictionary(dctx, dict, dictSize);
286            *legacyContext = dctx;
287            return 0;
288        }
289#endif
290#if (ZSTD_LEGACY_SUPPORT <= 7)
291        case 7 :
292        {
293            ZBUFFv07_DCtx* dctx = (prevVersion != newVersion) ? ZBUFFv07_createDCtx() : (ZBUFFv07_DCtx*)*legacyContext;
294            if (dctx==NULL) return ERROR(memory_allocation);
295            ZBUFFv07_decompressInitDictionary(dctx, dict, dictSize);
296            *legacyContext = dctx;
297            return 0;
298        }
299#endif
300    }
301}
302
303
304
305MEM_STATIC size_t ZSTD_decompressLegacyStream(void* legacyContext, U32 version,
306                                              ZSTD_outBuffer* output, ZSTD_inBuffer* input)
307{
308    DEBUGLOG(5, "ZSTD_decompressLegacyStream for v0.%u", version);
309    switch(version)
310    {
311        default :
312        case 1 :
313        case 2 :
314        case 3 :
315            (void)legacyContext; (void)output; (void)input;
316            return ERROR(version_unsupported);
317#if (ZSTD_LEGACY_SUPPORT <= 4)
318        case 4 :
319            {
320                ZBUFFv04_DCtx* dctx = (ZBUFFv04_DCtx*) legacyContext;
321                const void* src = (const char*)input->src + input->pos;
322                size_t readSize = input->size - input->pos;
323                void* dst = (char*)output->dst + output->pos;
324                size_t decodedSize = output->size - output->pos;
325                size_t const hintSize = ZBUFFv04_decompressContinue(dctx, dst, &decodedSize, src, &readSize);
326                output->pos += decodedSize;
327                input->pos += readSize;
328                return hintSize;
329            }
330#endif
331#if (ZSTD_LEGACY_SUPPORT <= 5)
332        case 5 :
333            {
334                ZBUFFv05_DCtx* dctx = (ZBUFFv05_DCtx*) legacyContext;
335                const void* src = (const char*)input->src + input->pos;
336                size_t readSize = input->size - input->pos;
337                void* dst = (char*)output->dst + output->pos;
338                size_t decodedSize = output->size - output->pos;
339                size_t const hintSize = ZBUFFv05_decompressContinue(dctx, dst, &decodedSize, src, &readSize);
340                output->pos += decodedSize;
341                input->pos += readSize;
342                return hintSize;
343            }
344#endif
345#if (ZSTD_LEGACY_SUPPORT <= 6)
346        case 6 :
347            {
348                ZBUFFv06_DCtx* dctx = (ZBUFFv06_DCtx*) legacyContext;
349                const void* src = (const char*)input->src + input->pos;
350                size_t readSize = input->size - input->pos;
351                void* dst = (char*)output->dst + output->pos;
352                size_t decodedSize = output->size - output->pos;
353                size_t const hintSize = ZBUFFv06_decompressContinue(dctx, dst, &decodedSize, src, &readSize);
354                output->pos += decodedSize;
355                input->pos += readSize;
356                return hintSize;
357            }
358#endif
359#if (ZSTD_LEGACY_SUPPORT <= 7)
360        case 7 :
361            {
362                ZBUFFv07_DCtx* dctx = (ZBUFFv07_DCtx*) legacyContext;
363                const void* src = (const char*)input->src + input->pos;
364                size_t readSize = input->size - input->pos;
365                void* dst = (char*)output->dst + output->pos;
366                size_t decodedSize = output->size - output->pos;
367                size_t const hintSize = ZBUFFv07_decompressContinue(dctx, dst, &decodedSize, src, &readSize);
368                output->pos += decodedSize;
369                input->pos += readSize;
370                return hintSize;
371            }
372#endif
373    }
374}
375
376
377#if defined (__cplusplus)
378}
379#endif
380
381#endif   /* ZSTD_LEGACY_H */
382