projects / wxWidgets.git / blame
| Commit | Line | Data |
|---|---|---|
| c801d85f | 1 | /* compress.c -- compress a memory buffer |
| a4019ec2 | 2 | * Copyright (C) 1995-2002 Jean-loup Gailly. |
| e6ebb514 | 3 | * For conditions of distribution and use, see copyright notice in zlib.h |
| c801d85f KB |
4 | */ |
| 5 | ||
| 6 | /* @(#) $Id$ */ | |
| 7 | ||
| 51dbdf87 VS |
8 | #define ZLIB_INTERNAL |
| 9 | #include "zlib.h" | |
| c801d85f KB |
10 | |
| 11 | /* =========================================================================== | |
| 12 | Compresses the source buffer into the destination buffer. The level | |
| 13 | parameter has the same meaning as in deflateInit. sourceLen is the byte | |
| 14 | length of the source buffer. Upon entry, destLen is the total size of the | |
| 15 | destination buffer, which must be at least 0.1% larger than sourceLen plus | |
| 16 | 12 bytes. Upon exit, destLen is the actual size of the compressed buffer. | |
| 17 | ||
| 18 | compress2 returns Z_OK if success, Z_MEM_ERROR if there was not enough | |
| 19 | memory, Z_BUF_ERROR if there was not enough room in the output buffer, | |
| 20 | Z_STREAM_ERROR if the level parameter is invalid. | |
| 21 | */ | |
| 22 | int ZEXPORT compress2 (dest, destLen, source, sourceLen, level) | |
| 23 | Bytef *dest; | |
| 24 | uLongf *destLen; | |
| 25 | const Bytef *source; | |
| 26 | uLong sourceLen; | |
| 27 | int level; | |
| 28 | { | |
| 29 | z_stream stream; | |
| 30 | int err; | |
| 31 | ||
| 32 | stream.next_in = (Bytef*)source; | |
| 33 | stream.avail_in = (uInt)sourceLen; | |
| 34 | #ifdef MAXSEG_64K | |
| 35 | /* Check for source > 64K on 16-bit machine: */ | |
| 36 | if ((uLong)stream.avail_in != sourceLen) return Z_BUF_ERROR; | |
| 37 | #endif | |
| 38 | stream.next_out = dest; | |
| 39 | stream.avail_out = (uInt)*destLen; | |
| 40 | if ((uLong)stream.avail_out != *destLen) return Z_BUF_ERROR; | |
| 41 | ||
| 42 | stream.zalloc = (alloc_func)0; | |
| 43 | stream.zfree = (free_func)0; | |
| 44 | stream.opaque = (voidpf)0; | |
| 45 | ||
| 46 | err = deflateInit(&stream, level); | |
| 47 | if (err != Z_OK) return err; | |
| 48 | ||
| 49 | err = deflate(&stream, Z_FINISH); | |
| 50 | if (err != Z_STREAM_END) { | |
| 51 | deflateEnd(&stream); | |
| 52 | return err == Z_OK ? Z_BUF_ERROR : err; | |
| 53 | } | |
| 54 | *destLen = stream.total_out; | |
| 55 | ||
| 56 | err = deflateEnd(&stream); | |
| 57 | return err; | |
| 58 | } | |
| 59 | ||
| 60 | /* =========================================================================== | |
| 61 | */ | |
| 62 | int ZEXPORT compress (dest, destLen, source, sourceLen) | |
| 63 | Bytef *dest; | |
| 64 | uLongf *destLen; | |
| 65 | const Bytef *source; | |
| 66 | uLong sourceLen; | |
| 67 | { | |
| 68 | return compress2(dest, destLen, source, sourceLen, Z_DEFAULT_COMPRESSION); | |
| 69 | } | |
| 51dbdf87 VS |
70 | |
| 71 | /* =========================================================================== | |
| 72 | If the default memLevel or windowBits for deflateInit() is changed, then | |
| 73 | this function needs to be updated. | |
| 74 | */ | |
| 75 | uLong ZEXPORT compressBound (sourceLen) | |
| 76 | uLong sourceLen; | |
| 77 | { | |
| 78 | return sourceLen + (sourceLen >> 12) + (sourceLen >> 14) + 11; | |
| 79 | } |