1//===--- Compression.cpp - Compression implementation ---------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements compression functions.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/Support/Compression.h"
14#include "llvm/ADT/SmallVector.h"
15#include "llvm/ADT/StringRef.h"
16#include "llvm/Config/config.h"
17#include "llvm/Support/Compiler.h"
18#include "llvm/Support/Error.h"
19#include "llvm/Support/ErrorHandling.h"
20#if LLVM_ENABLE_ZLIB
21#include <zlib.h>
22#endif
23#if LLVM_ENABLE_ZSTD
24#include <zstd.h>
25#endif
26
27using namespace llvm;
28using namespace llvm::compression;
29
30const char *compression::getReasonIfUnsupported(compression::Format F) {
31 switch (F) {
32 case compression::Format::Zlib:
33 if (zlib::isAvailable())
34 return nullptr;
35 return "LLVM was not built with LLVM_ENABLE_ZLIB or did not find zlib at "
36 "build time";
37 case compression::Format::Zstd:
38 if (zstd::isAvailable())
39 return nullptr;
40 return "LLVM was not built with LLVM_ENABLE_ZSTD or did not find zstd at "
41 "build time";
42 }
43 llvm_unreachable("");
44}
45
46void compression::compress(Params P, ArrayRef<uint8_t> Input,
47 SmallVectorImpl<uint8_t> &Output) {
48 switch (P.format) {
49 case compression::Format::Zlib:
50 zlib::compress(Input, CompressedBuffer&: Output, Level: P.level);
51 break;
52 case compression::Format::Zstd:
53 zstd::compress(Input, CompressedBuffer&: Output, Level: P.level, EnableLdm: P.zstdEnableLdm);
54 break;
55 }
56}
57
58Error compression::decompress(DebugCompressionType T, ArrayRef<uint8_t> Input,
59 uint8_t *Output, size_t UncompressedSize) {
60 switch (formatFor(Type: T)) {
61 case compression::Format::Zlib:
62 return zlib::decompress(Input, Output, UncompressedSize);
63 case compression::Format::Zstd:
64 return zstd::decompress(Input, Output, UncompressedSize);
65 }
66 llvm_unreachable("");
67}
68
69Error compression::decompress(compression::Format F, ArrayRef<uint8_t> Input,
70 SmallVectorImpl<uint8_t> &Output,
71 size_t UncompressedSize) {
72 switch (F) {
73 case compression::Format::Zlib:
74 return zlib::decompress(Input, Output, UncompressedSize);
75 case compression::Format::Zstd:
76 return zstd::decompress(Input, Output, UncompressedSize);
77 }
78 llvm_unreachable("");
79}
80
81Error compression::decompress(DebugCompressionType T, ArrayRef<uint8_t> Input,
82 SmallVectorImpl<uint8_t> &Output,
83 size_t UncompressedSize) {
84 return decompress(F: formatFor(Type: T), Input, Output, UncompressedSize);
85}
86
87#if LLVM_ENABLE_ZLIB
88
89static StringRef convertZlibCodeToString(int Code) {
90 switch (Code) {
91 case Z_MEM_ERROR:
92 return "zlib error: Z_MEM_ERROR";
93 case Z_BUF_ERROR:
94 return "zlib error: Z_BUF_ERROR";
95 case Z_STREAM_ERROR:
96 return "zlib error: Z_STREAM_ERROR";
97 case Z_DATA_ERROR:
98 return "zlib error: Z_DATA_ERROR";
99 case Z_OK:
100 default:
101 llvm_unreachable("unknown or unexpected zlib status code");
102 }
103}
104
105bool zlib::isAvailable() { return true; }
106
107void zlib::compress(ArrayRef<uint8_t> Input,
108 SmallVectorImpl<uint8_t> &CompressedBuffer, int Level) {
109 unsigned long CompressedSize = ::compressBound(sourceLen: Input.size());
110 CompressedBuffer.resize_for_overwrite(N: CompressedSize);
111 int Res = ::compress2(dest: (Bytef *)CompressedBuffer.data(), destLen: &CompressedSize,
112 source: (const Bytef *)Input.data(), sourceLen: Input.size(), level: Level);
113 if (Res == Z_MEM_ERROR)
114 report_bad_alloc_error(Reason: "Allocation failed");
115 assert(Res == Z_OK);
116 // Tell MemorySanitizer that zlib output buffer is fully initialized.
117 // This avoids a false report when running LLVM with uninstrumented ZLib.
118 __msan_unpoison(CompressedBuffer.data(), CompressedSize);
119 if (CompressedSize < CompressedBuffer.size())
120 CompressedBuffer.truncate(N: CompressedSize);
121}
122
123Error zlib::decompress(ArrayRef<uint8_t> Input, uint8_t *Output,
124 size_t &UncompressedSize) {
125 int Res = ::uncompress(dest: (Bytef *)Output, destLen: (uLongf *)&UncompressedSize,
126 source: (const Bytef *)Input.data(), sourceLen: Input.size());
127 // Tell MemorySanitizer that zlib output buffer is fully initialized.
128 // This avoids a false report when running LLVM with uninstrumented ZLib.
129 __msan_unpoison(Output, UncompressedSize);
130 return Res ? make_error<StringError>(Args: convertZlibCodeToString(Code: Res),
131 Args: inconvertibleErrorCode())
132 : Error::success();
133}
134
135Error zlib::decompress(ArrayRef<uint8_t> Input,
136 SmallVectorImpl<uint8_t> &Output,
137 size_t UncompressedSize) {
138 Output.resize_for_overwrite(N: UncompressedSize);
139 Error E = zlib::decompress(Input, Output: Output.data(), UncompressedSize);
140 if (UncompressedSize < Output.size())
141 Output.truncate(N: UncompressedSize);
142 return E;
143}
144
145#else
146bool zlib::isAvailable() { return false; }
147void zlib::compress(ArrayRef<uint8_t> Input,
148 SmallVectorImpl<uint8_t> &CompressedBuffer, int Level) {
149 llvm_unreachable("zlib::compress is unavailable");
150}
151Error zlib::decompress(ArrayRef<uint8_t> Input, uint8_t *UncompressedBuffer,
152 size_t &UncompressedSize) {
153 llvm_unreachable("zlib::decompress is unavailable");
154}
155Error zlib::decompress(ArrayRef<uint8_t> Input,
156 SmallVectorImpl<uint8_t> &UncompressedBuffer,
157 size_t UncompressedSize) {
158 llvm_unreachable("zlib::decompress is unavailable");
159}
160#endif
161
162#if LLVM_ENABLE_ZSTD
163
164bool zstd::isAvailable() { return true; }
165
166#include <zstd.h> // Ensure ZSTD library is included
167
168void zstd::compress(ArrayRef<uint8_t> Input,
169 SmallVectorImpl<uint8_t> &CompressedBuffer, int Level,
170 bool EnableLdm) {
171 ZSTD_CCtx *Cctx = ZSTD_createCCtx();
172 if (!Cctx)
173 report_bad_alloc_error(Reason: "Failed to create ZSTD_CCtx");
174
175 if (ZSTD_isError(code: ZSTD_CCtx_setParameter(
176 cctx: Cctx, param: ZSTD_c_enableLongDistanceMatching, value: EnableLdm ? 1 : 0))) {
177 ZSTD_freeCCtx(cctx: Cctx);
178 report_bad_alloc_error(Reason: "Failed to set ZSTD_c_enableLongDistanceMatching");
179 }
180
181 if (ZSTD_isError(
182 code: ZSTD_CCtx_setParameter(cctx: Cctx, param: ZSTD_c_compressionLevel, value: Level))) {
183 ZSTD_freeCCtx(cctx: Cctx);
184 report_bad_alloc_error(Reason: "Failed to set ZSTD_c_compressionLevel");
185 }
186
187 unsigned long CompressedBufferSize = ZSTD_compressBound(srcSize: Input.size());
188 CompressedBuffer.resize_for_overwrite(N: CompressedBufferSize);
189
190 size_t const CompressedSize =
191 ZSTD_compress2(cctx: Cctx, dst: CompressedBuffer.data(), dstCapacity: CompressedBufferSize,
192 src: Input.data(), srcSize: Input.size());
193
194 ZSTD_freeCCtx(cctx: Cctx);
195
196 if (ZSTD_isError(code: CompressedSize))
197 report_bad_alloc_error(Reason: "Compression failed");
198
199 __msan_unpoison(CompressedBuffer.data(), CompressedSize);
200 if (CompressedSize < CompressedBuffer.size())
201 CompressedBuffer.truncate(N: CompressedSize);
202}
203
204Error zstd::decompress(ArrayRef<uint8_t> Input, uint8_t *Output,
205 size_t &UncompressedSize) {
206 const size_t Res = ::ZSTD_decompress(
207 dst: Output, dstCapacity: UncompressedSize, src: (const uint8_t *)Input.data(), compressedSize: Input.size());
208 UncompressedSize = Res;
209 if (ZSTD_isError(code: Res))
210 return make_error<StringError>(Args: ZSTD_getErrorName(code: Res),
211 Args: inconvertibleErrorCode());
212 // Tell MemorySanitizer that zstd output buffer is fully initialized.
213 // This avoids a false report when running LLVM with uninstrumented ZLib.
214 __msan_unpoison(Output, UncompressedSize);
215 return Error::success();
216}
217
218Error zstd::decompress(ArrayRef<uint8_t> Input,
219 SmallVectorImpl<uint8_t> &Output,
220 size_t UncompressedSize) {
221 Output.resize_for_overwrite(N: UncompressedSize);
222 Error E = zstd::decompress(Input, Output: Output.data(), UncompressedSize);
223 if (UncompressedSize < Output.size())
224 Output.truncate(N: UncompressedSize);
225 return E;
226}
227
228#else
229bool zstd::isAvailable() { return false; }
230void zstd::compress(ArrayRef<uint8_t> Input,
231 SmallVectorImpl<uint8_t> &CompressedBuffer, int Level,
232 bool EnableLdm) {
233 llvm_unreachable("zstd::compress is unavailable");
234}
235Error zstd::decompress(ArrayRef<uint8_t> Input, uint8_t *Output,
236 size_t &UncompressedSize) {
237 llvm_unreachable("zstd::decompress is unavailable");
238}
239Error zstd::decompress(ArrayRef<uint8_t> Input,
240 SmallVectorImpl<uint8_t> &Output,
241 size_t UncompressedSize) {
242 llvm_unreachable("zstd::decompress is unavailable");
243}
244#endif
245