diff options
Diffstat (limited to 'deflate.c')
| -rw-r--r-- | deflate.c | 263 |
1 files changed, 198 insertions, 65 deletions
@@ -1,5 +1,5 @@ /* deflate.c -- compress data using the deflation algorithm - * Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler + * Copyright (C) 1995-2013 Jean-loup Gailly and Mark Adler * For conditions of distribution and use, see copyright notice in zlib.h */ @@ -37,7 +37,7 @@ * REFERENCES * * Deutsch, L.P.,"DEFLATE Compressed Data Format Specification". - * Available in http://www.ietf.org/rfc/rfc1951.txt + * Available in http://tools.ietf.org/html/rfc1951 * * A description of the Rabin and Karp algorithm is given in the book * "Algorithms" by R. Sedgewick, Addison-Wesley, p252. @@ -52,7 +52,7 @@ #include "deflate.h" const char deflate_copyright[] = - " deflate 1.2.5 Copyright 1995-2010 Jean-loup Gailly and Mark Adler "; + " deflate 1.2.8 Copyright 1995-2013 Jean-loup Gailly and Mark Adler "; /* If you use the zlib library in a product, an acknowledgment is welcome in the documentation of your product. If for some reason you cannot @@ -155,6 +155,9 @@ local const config configuration_table[10] = { struct static_tree_desc_s {int dummy;}; /* for buggy compilers */ #endif +/* rank Z_BLOCK between Z_NO_FLUSH and Z_PARTIAL_FLUSH */ +#define RANK(f) (((f) << 1) - ((f) > 4 ? 9 : 0)) + /* =========================================================================== * Update a hash value with the given input byte * IN assertion: all calls to to UPDATE_HASH are made with consecutive @@ -235,10 +238,19 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy, strm->msg = Z_NULL; if (strm->zalloc == (alloc_func)0) { +#ifdef Z_SOLO + return Z_STREAM_ERROR; +#else strm->zalloc = zcalloc; strm->opaque = (voidpf)0; +#endif } - if (strm->zfree == (free_func)0) strm->zfree = zcfree; + if (strm->zfree == (free_func)0) +#ifdef Z_SOLO + return Z_STREAM_ERROR; +#else + strm->zfree = zcfree; +#endif #ifdef FASTEST if (level != 0) level = 1; @@ -293,7 +305,7 @@ int ZEXPORT deflateInit2_(strm, level, method, windowBits, memLevel, strategy, if (s->window == Z_NULL || s->prev == Z_NULL || s->head == Z_NULL || s->pending_buf == Z_NULL) { s->status = FINISH_STATE; - strm->msg = (char*)ERR_MSG(Z_MEM_ERROR); + strm->msg = ERR_MSG(Z_MEM_ERROR); deflateEnd (strm); return Z_MEM_ERROR; } @@ -314,43 +326,70 @@ int ZEXPORT deflateSetDictionary (strm, dictionary, dictLength) uInt dictLength; { deflate_state *s; - uInt length = dictLength; - uInt n; - IPos hash_head = 0; + uInt str, n; + int wrap; + unsigned avail; + z_const unsigned char *next; - if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL || - strm->state->wrap == 2 || - (strm->state->wrap == 1 && strm->state->status != INIT_STATE)) + if (strm == Z_NULL || strm->state == Z_NULL || dictionary == Z_NULL) return Z_STREAM_ERROR; - s = strm->state; - if (s->wrap) - strm->adler = adler32(strm->adler, dictionary, dictLength); + wrap = s->wrap; + if (wrap == 2 || (wrap == 1 && s->status != INIT_STATE) || s->lookahead) + return Z_STREAM_ERROR; - if (length < MIN_MATCH) return Z_OK; - if (length > s->w_size) { - length = s->w_size; - dictionary += dictLength - length; /* use the tail of the dictionary */ + /* when using zlib wrappers, compute Adler-32 for provided dictionary */ + if (wrap == 1) + strm->adler = adler32(strm->adler, dictionary, dictLength); + s->wrap = 0; /* avoid computing Adler-32 in read_buf */ + + /* if dictionary would fill window, just replace the history */ + if (dictLength >= s->w_size) { + if (wrap == 0) { /* already empty otherwise */ + CLEAR_HASH(s); + s->strstart = 0; + s->block_start = 0L; + s->insert = 0; + } + dictionary += dictLength - s->w_size; /* use the tail */ + dictLength = s->w_size; } - zmemcpy(s->window, dictionary, length); - s->strstart = length; - s->block_start = (long)length; - /* Insert all strings in the hash table (except for the last two bytes). - * s->lookahead stays null, so s->ins_h will be recomputed at the next - * call of fill_window. - */ - s->ins_h = s->window[0]; - UPDATE_HASH(s, s->ins_h, s->window[1]); - for (n = 0; n <= length - MIN_MATCH; n++) { - INSERT_STRING(s, n, hash_head); + /* insert dictionary into window and hash */ + avail = strm->avail_in; + next = strm->next_in; + strm->avail_in = dictLength; + strm->next_in = (z_const Bytef *)dictionary; + fill_window(s); + while (s->lookahead >= MIN_MATCH) { + str = s->strstart; + n = s->lookahead - (MIN_MATCH-1); + do { + UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); +#ifndef FASTEST + s->prev[str & s->w_mask] = s->head[s->ins_h]; +#endif + s->head[s->ins_h] = (Pos)str; + str++; + } while (--n); + s->strstart = str; + s->lookahead = MIN_MATCH-1; + fill_window(s); } - if (hash_head) hash_head = 0; /* to make compiler happy */ + s->strstart += s->lookahead; + s->block_start = (long)s->strstart; + s->insert = s->lookahead; + s->lookahead = 0; + s->match_length = s->prev_length = MIN_MATCH-1; + s->match_available = 0; + strm->next_in = next; + strm->avail_in = avail; + s->wrap = wrap; return Z_OK; } /* ========================================================================= */ -int ZEXPORT deflateReset (strm) +int ZEXPORT deflateResetKeep (strm) z_streamp strm; { deflate_state *s; @@ -380,12 +419,23 @@ int ZEXPORT deflateReset (strm) s->last_flush = Z_NO_FLUSH; _tr_init(s); - lm_init(s); return Z_OK; } /* ========================================================================= */ +int ZEXPORT deflateReset (strm) + z_streamp strm; +{ + int ret; + + ret = deflateResetKeep(strm); + if (ret == Z_OK) + lm_init(strm->state); + return ret; +} + +/* ========================================================================= */ int ZEXPORT deflateSetHeader (strm, head) z_streamp strm; gz_headerp head; @@ -397,14 +447,42 @@ int ZEXPORT deflateSetHeader (strm, head) } /* ========================================================================= */ +int ZEXPORT deflatePending (strm, pending, bits) + unsigned *pending; + int *bits; + z_streamp strm; +{ + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + if (pending != Z_NULL) + *pending = strm->state->pending; + if (bits != Z_NULL) + *bits = strm->state->bi_valid; + return Z_OK; +} + +/* ========================================================================= */ int ZEXPORT deflatePrime (strm, bits, value) z_streamp strm; int bits; int value; { + deflate_state *s; + int put; + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; - strm->state->bi_valid = bits; - strm->state->bi_buf = (ush)(value & ((1 << bits) - 1)); + s = strm->state; + if ((Bytef *)(s->d_buf) < s->pending_out + ((Buf_size + 7) >> 3)) + return Z_BUF_ERROR; + do { + put = Buf_size - s->bi_valid; + if (put > bits) + put = bits; + s->bi_buf |= (ush)((value & ((1 << put) - 1)) << s->bi_valid); + s->bi_valid += put; + _tr_flush_bits(s); + value >>= put; + bits -= put; + } while (bits); return Z_OK; } @@ -435,6 +513,8 @@ int ZEXPORT deflateParams(strm, level, strategy) strm->total_in != 0) { /* Flush the last buffer: */ err = deflate(strm, Z_BLOCK); + if (err == Z_BUF_ERROR && s->pending == 0) + err = Z_OK; } if (s->level != level) { s->level = level; @@ -562,19 +642,22 @@ local void putShortMSB (s, b) local void flush_pending(strm) z_streamp strm; { - unsigned len = strm->state->pending; + unsigned len; + deflate_state *s = strm->state; + _tr_flush_bits(s); + len = s->pending; if (len > strm->avail_out) len = strm->avail_out; if (len == 0) return; - zmemcpy(strm->next_out, strm->state->pending_out, len); + zmemcpy(strm->next_out, s->pending_out, len); strm->next_out += len; - strm->state->pending_out += len; + s->pending_out += len; strm->total_out += len; strm->avail_out -= len; - strm->state->pending -= len; - if (strm->state->pending == 0) { - strm->state->pending_out = strm->state->pending_buf; + s->pending -= len; + if (s->pending == 0) { + s->pending_out = s->pending_buf; } } @@ -801,7 +884,7 @@ int ZEXPORT deflate (strm, flush) * flushes. For repeated and useless calls with Z_FINISH, we keep * returning Z_STREAM_END instead of Z_BUF_ERROR. */ - } else if (strm->avail_in == 0 && flush <= old_flush && + } else if (strm->avail_in == 0 && RANK(flush) <= RANK(old_flush) && flush != Z_FINISH) { ERR_RETURN(strm, Z_BUF_ERROR); } @@ -850,6 +933,7 @@ int ZEXPORT deflate (strm, flush) if (s->lookahead == 0) { s->strstart = 0; s->block_start = 0L; + s->insert = 0; } } } @@ -945,12 +1029,12 @@ int ZEXPORT deflateCopy (dest, source) ss = source->state; - zmemcpy(dest, source, sizeof(z_stream)); + zmemcpy((voidpf)dest, (voidpf)source, sizeof(z_stream)); ds = (deflate_state *) ZALLOC(dest, 1, sizeof(deflate_state)); if (ds == Z_NULL) return Z_MEM_ERROR; dest->state = (struct internal_state FAR *) ds; - zmemcpy(ds, ss, sizeof(deflate_state)); + zmemcpy((voidpf)ds, (voidpf)ss, sizeof(deflate_state)); ds->strm = dest; ds->window = (Bytef *) ZALLOC(dest, ds->w_size, 2*sizeof(Byte)); @@ -966,8 +1050,8 @@ int ZEXPORT deflateCopy (dest, source) } /* following zmemcpy do not work for 16-bit MSDOS */ zmemcpy(ds->window, ss->window, ds->w_size * 2 * sizeof(Byte)); - zmemcpy(ds->prev, ss->prev, ds->w_size * sizeof(Pos)); - zmemcpy(ds->head, ss->head, ds->hash_size * sizeof(Pos)); + zmemcpy((voidpf)ds->prev, (voidpf)ss->prev, ds->w_size * sizeof(Pos)); + zmemcpy((voidpf)ds->head, (voidpf)ss->head, ds->hash_size * sizeof(Pos)); zmemcpy(ds->pending_buf, ss->pending_buf, (uInt)ds->pending_buf_size); ds->pending_out = ds->pending_buf + (ss->pending_out - ss->pending_buf); @@ -1001,15 +1085,15 @@ local int read_buf(strm, buf, size) strm->avail_in -= len; + zmemcpy(buf, strm->next_in, len); if (strm->state->wrap == 1) { - strm->adler = adler32(strm->adler, strm->next_in, len); + strm->adler = adler32(strm->adler, buf, len); } #ifdef GZIP else if (strm->state->wrap == 2) { - strm->adler = crc32(strm->adler, strm->next_in, len); + strm->adler = crc32(strm->adler, buf, len); } #endif - zmemcpy(buf, strm->next_in, len); strm->next_in += len; strm->total_in += len; @@ -1036,6 +1120,7 @@ local void lm_init (s) s->strstart = 0; s->block_start = 0L; s->lookahead = 0; + s->insert = 0; s->match_length = s->prev_length = MIN_MATCH-1; s->match_available = 0; s->ins_h = 0; @@ -1310,6 +1395,8 @@ local void fill_window(s) unsigned more; /* Amount of free space at the end of the window. */ uInt wsize = s->w_size; + Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead"); + do { more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); @@ -1362,7 +1449,7 @@ local void fill_window(s) #endif more += wsize; } - if (s->strm->avail_in == 0) return; + if (s->strm->avail_in == 0) break; /* If there was no sliding: * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && @@ -1381,12 +1468,24 @@ local void fill_window(s) s->lookahead += n; /* Initialize the hash value now that we have some input: */ - if (s->lookahead >= MIN_MATCH) { - s->ins_h = s->window[s->strstart]; - UPDATE_HASH(s, s->ins_h, s->window[s->strstart+1]); + if (s->lookahead + s->insert >= MIN_MATCH) { + uInt str = s->strstart - s->insert; + s->ins_h = s->window[str]; + UPDATE_HASH(s, s->ins_h, s->window[str + 1]); #if MIN_MATCH != 3 Call UPDATE_HASH() MIN_MATCH-3 more times #endif + while (s->insert) { + UPDATE_HASH(s, s->ins_h, s->window[str + MIN_MATCH-1]); +#ifndef FASTEST + s->prev[str & s->w_mask] = s->head[s->ins_h]; +#endif + s->head[s->ins_h] = (Pos)str; + str++; + s->insert--; + if (s->lookahead + s->insert < MIN_MATCH) + break; + } } /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, * but this is not important since only literal bytes will be emitted. @@ -1427,6 +1526,9 @@ local void fill_window(s) s->high_water += init; } } + + Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD, + "not enough room for search"); } /* =========================================================================== @@ -1506,8 +1608,14 @@ local block_state deflate_stored(s, flush) FLUSH_BLOCK(s, 0); } } - FLUSH_BLOCK(s, flush == Z_FINISH); - return flush == Z_FINISH ? finish_done : block_done; + s->insert = 0; + if (flush == Z_FINISH) { + FLUSH_BLOCK(s, 1); + return finish_done; + } + if ((long)s->strstart > s->block_start) + FLUSH_BLOCK(s, 0); + return block_done; } /* =========================================================================== @@ -1603,8 +1711,14 @@ local block_state deflate_fast(s, flush) } if (bflush) FLUSH_BLOCK(s, 0); } - FLUSH_BLOCK(s, flush == Z_FINISH); - return flush == Z_FINISH ? finish_done : block_done; + s->insert = s->strstart < MIN_MATCH-1 ? s->strstart : MIN_MATCH-1; + if (flush == Z_FINISH) { + FLUSH_BLOCK(s, 1); + return finish_done; + } + if (s->last_lit) + FLUSH_BLOCK(s, 0); + return block_done; } #ifndef FASTEST @@ -1728,8 +1842,14 @@ local block_state deflate_slow(s, flush) _tr_tally_lit(s, s->window[s->strstart-1], bflush); s->match_available = 0; } - FLUSH_BLOCK(s, flush == Z_FINISH); - return flush == Z_FINISH ? finish_done : block_done; + s->insert = s->strstart < MIN_MATCH-1 ? s->strstart : MIN_MATCH-1; + if (flush == Z_FINISH) { + FLUSH_BLOCK(s, 1); + return finish_done; + } + if (s->last_lit) + FLUSH_BLOCK(s, 0); + return block_done; } #endif /* FASTEST */ @@ -1749,11 +1869,11 @@ local block_state deflate_rle(s, flush) for (;;) { /* Make sure that we always have enough lookahead, except * at the end of the input file. We need MAX_MATCH bytes - * for the longest encodable run. + * for the longest run, plus one for the unrolled loop. */ - if (s->lookahead < MAX_MATCH) { + if (s->lookahead <= MAX_MATCH) { fill_window(s); - if (s->lookahead < MAX_MATCH && flush == Z_NO_FLUSH) { + if (s->lookahead <= MAX_MATCH && flush == Z_NO_FLUSH) { return need_more; } if (s->lookahead == 0) break; /* flush the current block */ @@ -1776,6 +1896,7 @@ local block_state deflate_rle(s, flush) if (s->match_length > s->lookahead) s->match_length = s->lookahead; } + Assert(scan <= s->window+(uInt)(s->window_size-1), "wild scan"); } /* Emit match if have run of MIN_MATCH or longer, else emit literal */ @@ -1796,8 +1917,14 @@ local block_state deflate_rle(s, flush) } if (bflush) FLUSH_BLOCK(s, 0); } - FLUSH_BLOCK(s, flush == Z_FINISH); - return flush == Z_FINISH ? finish_done : block_done; + s->insert = 0; + if (flush == Z_FINISH) { + FLUSH_BLOCK(s, 1); + return finish_done; + } + if (s->last_lit) + FLUSH_BLOCK(s, 0); + return block_done; } /* =========================================================================== @@ -1829,6 +1956,12 @@ local block_state deflate_huff(s, flush) s->strstart++; if (bflush) FLUSH_BLOCK(s, 0); } - FLUSH_BLOCK(s, flush == Z_FINISH); - return flush == Z_FINISH ? finish_done : block_done; + s->insert = 0; + if (flush == Z_FINISH) { + FLUSH_BLOCK(s, 1); + return finish_done; + } + if (s->last_lit) + FLUSH_BLOCK(s, 0); + return block_done; } |