| 1 | // |
| 2 | // ZIP file support |
| 3 | // This is here to simplify interfacing to zlib, as zlib does NO zip file handling |
| 4 | // |
| 5 | // by James Hammons |
| 6 | // (C) 2012 Underground Software |
| 7 | // |
| 8 | // JLH = James Hammons <jlhamm@acm.org> |
| 9 | // |
| 10 | // Who When What |
| 11 | // --- ---------- ------------------------------------------------------------- |
| 12 | // JLH 01/16/2010 Created this log ;-) |
| 13 | // JLH 02/28/2010 Removed unnecessary cruft |
| 14 | // JLH 05/31/2012 Rewrote everything and removed all MAME code |
| 15 | // |
| 16 | |
| 17 | #include "unzip.h" |
| 18 | |
| 19 | #include <stdlib.h> |
| 20 | #include <string.h> |
| 21 | #include <zlib.h> |
| 22 | #include "log.h" |
| 23 | |
| 24 | |
| 25 | uint32_t GetLong(FILE * fp) |
| 26 | { |
| 27 | uint32_t n = ((uint32_t)fgetc(fp)); |
| 28 | n |= ((uint32_t)fgetc(fp)) << 8; |
| 29 | n |= ((uint32_t)fgetc(fp)) << 16; |
| 30 | n |= ((uint32_t)fgetc(fp)) << 24; |
| 31 | |
| 32 | return n; |
| 33 | } |
| 34 | |
| 35 | |
| 36 | uint16_t GetWord(FILE * fp) |
| 37 | { |
| 38 | uint16_t n = ((uint16_t)fgetc(fp)); |
| 39 | n |= ((uint16_t)fgetc(fp)) << 8; |
| 40 | |
| 41 | return n; |
| 42 | } |
| 43 | |
| 44 | |
| 45 | bool GetZIPHeader(FILE * fp, ZipFileEntry & ze) |
| 46 | { |
| 47 | ze.signature = GetLong(fp); |
| 48 | ze.version = GetWord(fp); |
| 49 | ze.flags = GetWord(fp); |
| 50 | ze.method = GetWord(fp); |
| 51 | ze.modifiedTime = GetWord(fp); |
| 52 | ze.modifiedDate = GetWord(fp); |
| 53 | ze.crc32 = GetLong(fp); |
| 54 | ze.compressedSize = GetLong(fp); |
| 55 | ze.uncompressedSize = GetLong(fp); |
| 56 | ze.filenameLength = GetWord(fp); |
| 57 | ze.extraLength = GetWord(fp); |
| 58 | |
| 59 | // This handling is really ungraceful; but if someone is going to feed us |
| 60 | // shit, then why eat it? :-) |
| 61 | if (ze.filenameLength < 512) |
| 62 | { |
| 63 | fread(ze.filename, 1, ze.filenameLength, fp); |
| 64 | ze.filename[ze.filenameLength] = 0; |
| 65 | } |
| 66 | else |
| 67 | { |
| 68 | fseek(fp, ze.filenameLength, SEEK_CUR); |
| 69 | ze.filename[0] = 0; |
| 70 | } |
| 71 | |
| 72 | // Skip the "extra" header |
| 73 | fseek(fp, ze.extraLength, SEEK_CUR); |
| 74 | |
| 75 | return (ze.signature == 0x04034B50 ? true : false); |
| 76 | } |
| 77 | |
| 78 | |
| 79 | // |
| 80 | // Uncompress a file from a ZIP file filestream |
| 81 | // NOTE: The passed in buffer *must* be fully allocated before calling this! |
| 82 | // |
| 83 | #define CHUNKSIZE 16384 |
| 84 | int UncompressFileFromZIP(FILE * fp, ZipFileEntry ze, uint8_t * buffer) |
| 85 | { |
| 86 | z_stream zip; |
| 87 | unsigned char inBuffer[CHUNKSIZE]; |
| 88 | uint32_t remaining = ze.compressedSize; |
| 89 | |
| 90 | // Set up z_stream for inflating |
| 91 | zip.zalloc = Z_NULL; |
| 92 | zip.zfree = Z_NULL; |
| 93 | zip.opaque = Z_NULL; |
| 94 | zip.avail_in = 0; |
| 95 | zip.next_in = Z_NULL; |
| 96 | |
| 97 | int ret = inflateInit2(&zip, -MAX_WBITS); // -MAX_WBITS tells it there's no header |
| 98 | |
| 99 | // Bail if can't initialize the z_stream... |
| 100 | if (ret != Z_OK) |
| 101 | return ret; |
| 102 | |
| 103 | zip.avail_out = ze.uncompressedSize; |
| 104 | zip.next_out = buffer; |
| 105 | |
| 106 | // Decompress until deflate stream ends or we hit end of file |
| 107 | do |
| 108 | { |
| 109 | zip.avail_in = fread(inBuffer, 1, (remaining < CHUNKSIZE ? remaining : CHUNKSIZE), fp); |
| 110 | zip.next_in = inBuffer; |
| 111 | remaining -= CHUNKSIZE; |
| 112 | |
| 113 | if (ferror(fp)) |
| 114 | { |
| 115 | inflateEnd(&zip); |
| 116 | return Z_ERRNO; |
| 117 | } |
| 118 | |
| 119 | if (zip.avail_in == 0) |
| 120 | break; |
| 121 | |
| 122 | ret = inflate(&zip, Z_NO_FLUSH); |
| 123 | |
| 124 | if ((ret == Z_NEED_DICT) || (ret == Z_DATA_ERROR) || (ret == Z_MEM_ERROR)) |
| 125 | { |
| 126 | inflateEnd(&zip); |
| 127 | return ret; |
| 128 | } |
| 129 | |
| 130 | } |
| 131 | while (ret != Z_STREAM_END); |
| 132 | |
| 133 | inflateEnd(&zip); |
| 134 | |
| 135 | return (ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR); |
| 136 | } |