diff options
Diffstat (limited to 'lib/zlib/inflate.c')
| -rw-r--r-- | lib/zlib/inflate.c | 956 |
1 files changed, 956 insertions, 0 deletions
diff --git a/lib/zlib/inflate.c b/lib/zlib/inflate.c new file mode 100644 index 000000000..1eef609de --- /dev/null +++ b/lib/zlib/inflate.c @@ -0,0 +1,956 @@ +/* inflate.c -- zlib decompression + * Copyright (C) 1995-2005 Mark Adler + * For conditions of distribution and use, see copyright notice in zlib.h + */ +local void fixedtables OF((struct inflate_state FAR *state)); +local int updatewindow OF((z_streamp strm, unsigned out)); + +int ZEXPORT inflateReset(strm) +z_streamp strm; +{ + struct inflate_state FAR *state; + + if (strm == Z_NULL || strm->state == Z_NULL) return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + strm->total_in = strm->total_out = state->total = 0; + strm->msg = Z_NULL; + strm->adler = 1; /* to support ill-conceived Java test suite */ + state->mode = HEAD; + state->last = 0; + state->havedict = 0; + state->dmax = 32768U; + state->head = Z_NULL; + state->wsize = 0; + state->whave = 0; + state->write = 0; + state->hold = 0; + state->bits = 0; + state->lencode = state->distcode = state->next = state->codes; + WATCHDOG_RESET(); + Tracev((stderr, "inflate: reset\n")); + return Z_OK; +} + +int ZEXPORT inflateInit2_(strm, windowBits, version, stream_size) +z_streamp strm; +int windowBits; +const char *version; +int stream_size; +{ + struct inflate_state FAR *state; + + if (version == Z_NULL || version[0] != ZLIB_VERSION[0] || + stream_size != (int)(sizeof(z_stream))) + return Z_VERSION_ERROR; + if (strm == Z_NULL) return Z_STREAM_ERROR; + strm->msg = Z_NULL; /* in case we return an error */ + if (strm->zalloc == (alloc_func)0) { + strm->zalloc = zcalloc; + strm->opaque = (voidpf)0; + } + if (strm->zfree == (free_func)0) strm->zfree = zcfree; + state = (struct inflate_state FAR *) + ZALLOC(strm, 1, sizeof(struct inflate_state)); + if (state == Z_NULL) return Z_MEM_ERROR; + Tracev((stderr, "inflate: allocated\n")); + strm->state = (struct internal_state FAR *)state; + if (windowBits < 0) { + state->wrap = 0; + windowBits = -windowBits; + } + else { + state->wrap = (windowBits >> 4) + 1; +#ifdef GUNZIP + if (windowBits < 48) windowBits &= 15; +#endif + } + if (windowBits < 8 || windowBits > 15) { + ZFREE(strm, state); + strm->state = Z_NULL; + return Z_STREAM_ERROR; + } + state->wbits = (unsigned)windowBits; + state->window = Z_NULL; + return inflateReset(strm); +} + +int ZEXPORT inflateInit_(strm, version, stream_size) +z_streamp strm; +const char *version; +int stream_size; +{ + return inflateInit2_(strm, DEF_WBITS, version, stream_size); +} + +local void fixedtables(state) +struct inflate_state FAR *state; +{ + state->lencode = lenfix; + state->lenbits = 9; + state->distcode = distfix; + state->distbits = 5; +} + +/* + Update the window with the last wsize (normally 32K) bytes written before + returning. If window does not exist yet, create it. This is only called + when a window is already in use, or when output has been written during this + inflate call, but the end of the deflate stream has not been reached yet. + It is also called to create a window for dictionary data when a dictionary + is loaded. + + Providing output buffers larger than 32K to inflate() should provide a speed + advantage, since only the last 32K of output is copied to the sliding window + upon return from inflate(), and since all distances after the first 32K of + output will fall in the output data, making match copies simpler and faster. + The advantage may be dependent on the size of the processor's data caches. + */ +local int updatewindow(strm, out) +z_streamp strm; +unsigned out; +{ + struct inflate_state FAR *state; + unsigned copy, dist; + + state = (struct inflate_state FAR *)strm->state; + + /* if it hasn't been done already, allocate space for the window */ + if (state->window == Z_NULL) { + state->window = (unsigned char FAR *) + ZALLOC(strm, 1U << state->wbits, + sizeof(unsigned char)); + if (state->window == Z_NULL) return 1; + } + + /* if window not in use yet, initialize */ + if (state->wsize == 0) { + state->wsize = 1U << state->wbits; + state->write = 0; + state->whave = 0; + } + + /* copy state->wsize or less output bytes into the circular window */ + copy = out - strm->avail_out; + if (copy >= state->wsize) { + zmemcpy(state->window, strm->next_out - state->wsize, state->wsize); + state->write = 0; + state->whave = state->wsize; + } + else { + dist = state->wsize - state->write; + if (dist > copy) dist = copy; + zmemcpy(state->window + state->write, strm->next_out - copy, dist); + copy -= dist; + if (copy) { + zmemcpy(state->window, strm->next_out - copy, copy); + state->write = copy; + state->whave = state->wsize; + } + else { + state->write += dist; + if (state->write == state->wsize) state->write = 0; + if (state->whave < state->wsize) state->whave += dist; + } + } + return 0; +} + +/* Macros for inflate(): */ + +/* check function to use adler32() for zlib or crc32() for gzip */ +#ifdef GUNZIP +# define UPDATE(check, buf, len) \ + (state->flags ? crc32(check, buf, len) : adler32(check, buf, len)) +#else +# define UPDATE(check, buf, len) adler32(check, buf, len) +#endif + +/* check macros for header crc */ +#ifdef GUNZIP +# define CRC2(check, word) \ + do { \ + hbuf[0] = (unsigned char)(word); \ + hbuf[1] = (unsigned char)((word) >> 8); \ + check = crc32(check, hbuf, 2); \ + } while (0) + +# define CRC4(check, word) \ + do { \ + hbuf[0] = (unsigned char)(word); \ + hbuf[1] = (unsigned char)((word) >> 8); \ + hbuf[2] = (unsigned char)((word) >> 16); \ + hbuf[3] = (unsigned char)((word) >> 24); \ + check = crc32(check, hbuf, 4); \ + } while (0) +#endif + +/* Load registers with state in inflate() for speed */ +#define LOAD() \ + do { \ + put = strm->next_out; \ + left = strm->avail_out; \ + next = strm->next_in; \ + have = strm->avail_in; \ + hold = state->hold; \ + bits = state->bits; \ + } while (0) + +/* Restore state from registers in inflate() */ +#define RESTORE() \ + do { \ + strm->next_out = put; \ + strm->avail_out = left; \ + strm->next_in = next; \ + strm->avail_in = have; \ + state->hold = hold; \ + state->bits = bits; \ + } while (0) + +/* Clear the input bit accumulator */ +#define INITBITS() \ + do { \ + hold = 0; \ + bits = 0; \ + } while (0) + +/* Get a byte of input into the bit accumulator, or return from inflate() + if there is no input available. */ +#define PULLBYTE() \ + do { \ + if (have == 0) goto inf_leave; \ + have--; \ + hold += (unsigned long)(*next++) << bits; \ + bits += 8; \ + } while (0) + +/* Assure that there are at least n bits in the bit accumulator. If there is + not enough available input to do that, then return from inflate(). */ +#define NEEDBITS(n) \ + do { \ + while (bits < (unsigned)(n)) \ + PULLBYTE(); \ + } while (0) + +/* Return the low n bits of the bit accumulator (n < 16) */ +#define BITS(n) \ + ((unsigned)hold & ((1U << (n)) - 1)) + +/* Remove n bits from the bit accumulator */ +#define DROPBITS(n) \ + do { \ + hold >>= (n); \ + bits -= (unsigned)(n); \ + } while (0) + +/* Remove zero to seven bits as needed to go to a byte boundary */ +#define BYTEBITS() \ + do { \ + hold >>= bits & 7; \ + bits -= bits & 7; \ + } while (0) + +/* Reverse the bytes in a 32-bit value */ +#define REVERSE(q) \ + ((((q) >> 24) & 0xff) + (((q) >> 8) & 0xff00) + \ + (((q) & 0xff00) << 8) + (((q) & 0xff) << 24)) + +/* + inflate() uses a state machine to process as much input data and generate as + much output data as possible before returning. The state machine is + structured roughly as follows: + + for (;;) switch (state) { + ... + case STATEn: + if (not enough input data or output space to make progress) + return; + ... make progress ... + state = STATEm; + break; + ... + } + + so when inflate() is called again, the same case is attempted again, and + if the appropriate resources are provided, the machine proceeds to the + next state. The NEEDBITS() macro is usually the way the state evaluates + whether it can proceed or should return. NEEDBITS() does the return if + the requested bits are not available. The typical use of the BITS macros + is: + + NEEDBITS(n); + ... do something with BITS(n) ... + DROPBITS(n); + + where NEEDBITS(n) either returns from inflate() if there isn't enough + input left to load n bits into the accumulator, or it continues. BITS(n) + gives the low n bits in the accumulator. When done, DROPBITS(n) drops + the low n bits off the accumulator. INITBITS() clears the accumulator + and sets the number of available bits to zero. BYTEBITS() discards just + enough bits to put the accumulator on a byte boundary. After BYTEBITS() + and a NEEDBITS(8), then BITS(8) would return the next byte in the stream. + + NEEDBITS(n) uses PULLBYTE() to get an available byte of input, or to return + if there is no input available. The decoding of variable length codes uses + PULLBYTE() directly in order to pull just enough bytes to decode the next + code, and no more. + + Some states loop until they get enough input, making sure that enough + state information is maintained to continue the loop where it left off + if NEEDBITS() returns in the loop. For example, want, need, and keep + would all have to actually be part of the saved state in case NEEDBITS() + returns: + + case STATEw: + while (want < need) { + NEEDBITS(n); + keep[want++] = BITS(n); + DROPBITS(n); + } + state = STATEx; + case STATEx: + + As shown above, if the next state is also the next case, then the break + is omitted. + + A state may also return if there is not enough output space available to + complete that state. Those states are copying stored data, writing a + literal byte, and copying a matching string. + + When returning, a "goto inf_leave" is used to update the total counters, + update the check value, and determine whether any progress has been made + during that inflate() call in order to return the proper return code. + Progress is defined as a change in either strm->avail_in or strm->avail_out. + When there is a window, goto inf_leave will update the window with the last + output written. If a goto inf_leave occurs in the middle of decompression + and there is no window currently, goto inf_leave will create one and copy + output to the window for the next call of inflate(). + + In this implementation, the flush parameter of inflate() only affects the + return code (per zlib.h). inflate() always writes as much as possible to + strm->next_out, given the space available and the provided input--the effect + documented in zlib.h of Z_SYNC_FLUSH. Furthermore, inflate() always defers + the allocation of and copying into a sliding window until necessary, which + provides the effect documented in zlib.h for Z_FINISH when the entire input + stream available. So the only thing the flush parameter actually does is: + when flush is set to Z_FINISH, inflate() cannot return Z_OK. Instead it + will return Z_BUF_ERROR if it has not reached the end of the stream. + */ +int ZEXPORT inflate(strm, flush) +z_streamp strm; +int flush; +{ + struct inflate_state FAR *state; + unsigned char FAR *next; /* next input */ + unsigned char FAR *put; /* next output */ + unsigned have, left; /* available input and output */ + unsigned long hold; /* bit buffer */ + unsigned bits; /* bits in bit buffer */ + unsigned in, out; /* save starting available input and output */ + unsigned copy; /* number of stored or match bytes to copy */ + unsigned char FAR *from; /* where to copy match bytes from */ + code this; /* current decoding table entry */ + code last; /* parent table entry */ + unsigned len; /* length to copy for repeats, bits to drop */ + int ret; /* return code */ +#ifdef GUNZIP + unsigned char hbuf[4]; /* buffer for gzip header crc calculation */ +#endif + static const unsigned short order[19] = /* permutation of code lengths */ + {16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15}; + + if (strm == Z_NULL || strm->state == Z_NULL || + (strm->next_in == Z_NULL && strm->avail_in != 0)) + return Z_STREAM_ERROR; + + state = (struct inflate_state FAR *)strm->state; + if (state->mode == TYPE) state->mode = TYPEDO; /* skip check */ + LOAD(); + in = have; + out = left; + ret = Z_OK; + for (;;) + switch (state->mode) { + case HEAD: + if (state->wrap == 0) { + state->mode = TYPEDO; + break; + } + NEEDBITS(16); +#ifdef GUNZIP + if ((state->wrap & 2) && hold == 0x8b1f) { /* gzip header */ + state->check = crc32(0L, Z_NULL, 0); + CRC2(state->check, hold); + INITBITS(); + state->mode = FLAGS; + break; + } + state->flags = 0; /* expect zlib header */ + if (state->head != Z_NULL) + state->head->done = -1; + if (!(state->wrap & 1) || /* check if zlib header allowed */ +#else + if ( +#endif + ((BITS(8) << 8) + (hold >> 8)) % 31) { + strm->msg = (char *)"incorrect header check"; + state->mode = BAD; + break; + } + if (BITS(4) != Z_DEFLATED) { + strm->msg = (char *)"unknown compression method"; + state->mode = BAD; + break; + } + DROPBITS(4); + len = BITS(4) + 8; + if (len > state->wbits) { + strm->msg = (char *)"invalid window size"; + state->mode = BAD; + break; + } + state->dmax = 1U << len; + Tracev((stderr, "inflate: zlib header ok\n")); + strm->adler = state->check = adler32(0L, Z_NULL, 0); + state->mode = hold & 0x200 ? DICTID : TYPE; + INITBITS(); + break; +#ifdef GUNZIP + case FLAGS: + NEEDBITS(16); + state->flags = (int)(hold); + if ((state->flags & 0xff) != Z_DEFLATED) { + strm->msg = (char *)"unknown compression method"; + state->mode = BAD; + break; + } + if (state->flags & 0xe000) { + strm->msg = (char *)"unknown header flags set"; + state->mode = BAD; + break; + } + if (state->head != Z_NULL) + state->head->text = (int)((hold >> 8) & 1); + if (state->flags & 0x0200) CRC2(state->check, hold); + INITBITS(); + state->mode = TIME; + case TIME: + NEEDBITS(32); + if (state->head != Z_NULL) + state->head->time = hold; + if (state->flags & 0x0200) CRC4(state->check, hold); + INITBITS(); + state->mode = OS; + case OS: + NEEDBITS(16); + if (state->head != Z_NULL) { + state->head->xflags = (int)(hold & 0xff); + state->head->os = (int)(hold >> 8); + } + if (state->flags & 0x0200) CRC2(state->check, hold); + INITBITS(); + state->mode = EXLEN; + case EXLEN: + if (state->flags & 0x0400) { + NEEDBITS(16); + state->length = (unsigned)(hold); + if (state->head != Z_NULL) + state->head->extra_len = (unsigned)hold; + if (state->flags & 0x0200) CRC2(state->check, hold); + INITBITS(); + } + else if (state->head != Z_NULL) + state->head->extra = Z_NULL; + state->mode = EXTRA; + case EXTRA: + if (state->flags & 0x0400) { + copy = state->length; + if (copy > have) copy = have; + if (copy) { + if (state->head != Z_NULL && + state->head->extra != Z_NULL) { + len = state->head->extra_len - state->length; + zmemcpy(state->head->extra + len, next, + len + copy > state->head->extra_max ? + state->head->extra_max - len : copy); + } + if (state->flags & 0x0200) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + state->length -= copy; + } + if (state->length) goto inf_leave; + } + state->length = 0; + state->mode = NAME; + case NAME: + if (state->flags & 0x0800) { + if (have == 0) goto inf_leave; + copy = 0; + do { + len = (unsigned)(next[copy++]); + if (state->head != Z_NULL && + state->head->name != Z_NULL && + state->length < state->head->name_max) + state->head->name[state->length++] = len; + } while (len && copy < have); + if (state->flags & 0x0200) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + if (len) goto inf_leave; + } + else if (state->head != Z_NULL) + state->head->name = Z_NULL; + state->length = 0; + state->mode = COMMENT; + case COMMENT: + if (state->flags & 0x1000) { + if (have == 0) goto inf_leave; + copy = 0; + do { + len = (unsigned)(next[copy++]); + if (state->head != Z_NULL && + state->head->comment != Z_NULL && + state->length < state->head->comm_max) + state->head->comment[state->length++] = len; + } while (len && copy < have); + if (state->flags & 0x0200) + state->check = crc32(state->check, next, copy); + have -= copy; + next += copy; + if (len) goto inf_leave; + } + else if (state->head != Z_NULL) + state->head->comment = Z_NULL; + state->mode = HCRC; + case HCRC: + if (state->flags & 0x0200) { + NEEDBITS(16); + if (hold != (state->check & 0xffff)) { + strm->msg = (char *)"header crc mismatch"; + state->mode = BAD; + break; + } + INITBITS(); + } + if (state->head != Z_NULL) { + state->head->hcrc = (int)((state->flags >> 9) & 1); + state->head->done = 1; + } + strm->adler = state->check = crc32(0L, Z_NULL, 0); + state->mode = TYPE; + break; +#endif + case DICTID: + NEEDBITS(32); + strm->adler = state->check = REVERSE(hold); + INITBITS(); + state->mode = DICT; + case DICT: + if (state->havedict == 0) { + RESTORE(); + return Z_NEED_DICT; + } + strm->adler = state->check = adler32(0L, Z_NULL, 0); + state->mode = TYPE; + case TYPE: + WATCHDOG_RESET(); + if (flush == Z_BLOCK) goto inf_leave; + case TYPEDO: + if (state->last) { + BYTEBITS(); + state->mode = CHECK; + break; + } + NEEDBITS(3); + state->last = BITS(1); + DROPBITS(1); + switch (BITS(2)) { + case 0: /* stored block */ + Tracev((stderr, "inflate: stored block%s\n", + state->last ? " (last)" : "")); + state->mode = STORED; + break; + case 1: /* fixed block */ + fixedtables(state); + Tracev((stderr, "inflate: fixed codes block%s\n", + state->last ? " (last)" : "")); + state->mode = LEN; /* decode codes */ + break; + case 2: /* dynamic block */ + Tracev((stderr, "inflate: dynamic codes block%s\n", + state->last ? " (last)" : "")); + state->mode = TABLE; + break; + case 3: + strm->msg = (char *)"invalid block type"; + state->mode = BAD; + } + DROPBITS(2); + break; + case STORED: + BYTEBITS(); /* go to byte boundary */ + NEEDBITS(32); + if ((hold & 0xffff) != ((hold >> 16) ^ 0xffff)) { + strm->msg = (char *)"invalid stored block lengths"; + state->mode = BAD; + break; + } + state->length = (unsigned)hold & 0xffff; + Tracev((stderr, "inflate: stored length %u\n", + state->length)); + INITBITS(); + state->mode = COPY; + case COPY: + copy = state->length; + if (copy) { + if (copy > have) copy = have; + if (copy > left) copy = left; + if (copy == 0) goto inf_leave; + zmemcpy(put, next, copy); + have -= copy; + next += copy; + left -= copy; + put += copy; + state->length -= copy; + break; + } + Tracev((stderr, "inflate: stored end\n")); + state->mode = TYPE; + break; + case TABLE: + NEEDBITS(14); + state->nlen = BITS(5) + 257; + DROPBITS(5); + state->ndist = BITS(5) + 1; + DROPBITS(5); + state->ncode = BITS(4) + 4; + DROPBITS(4); +#ifndef PKZIP_BUG_WORKAROUND + if (state->nlen > 286 || state->ndist > 30) { + strm->msg = (char *)"too many length or distance symbols"; + state->mode = BAD; + break; + } +#endif + Tracev((stderr, "inflate: table sizes ok\n")); + state->have = 0; + state->mode = LENLENS; + case LENLENS: + while (state->have < state->ncode) { + NEEDBITS(3); + state->lens[order[state->have++]] = (unsigned short)BITS(3); + DROPBITS(3); + } + while (state->have < 19) + state->lens[order[state->have++]] = 0; + state->next = state->codes; + state->lencode = (code const FAR *)(state->next); + state->lenbits = 7; + ret = inflate_table(CODES, state->lens, 19, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid code lengths set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: code lengths ok\n")); + state->have = 0; + state->mode = CODELENS; + case CODELENS: + while (state->have < state->nlen + state->ndist) { + for (;;) { + this = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if (this.val < 16) { + NEEDBITS(this.bits); + DROPBITS(this.bits); + state->lens[state->have++] = this.val; + } + else { + if (this.val == 16) { + NEEDBITS(this.bits + 2); + DROPBITS(this.bits); + if (state->have == 0) { + strm->msg = (char *)"invalid bit length repeat"; + state->mode = BAD; + break; + } + len = state->lens[state->have - 1]; + copy = 3 + BITS(2); + DROPBITS(2); + } + else if (this.val == 17) { + NEEDBITS(this.bits + 3); + DROPBITS(this.bits); + len = 0; + copy = 3 + BITS(3); + DROPBITS(3); + } + else { + NEEDBITS(this.bits + 7); + DROPBITS(this.bits); + len = 0; + copy = 11 + BITS(7); + DROPBITS(7); + } + if (state->have + copy > state->nlen + state->ndist) { + strm->msg = (char *)"invalid bit length repeat"; + state->mode = BAD; + break; + } + while (copy--) + state->lens[state->have++] = (unsigned short)len; + } + } + + /* handle error breaks in while */ + if (state->mode == BAD) break; + + /* build code tables */ + state->next = state->codes; + state->lencode = (code const FAR *)(state->next); + state->lenbits = 9; + ret = inflate_table(LENS, state->lens, state->nlen, &(state->next), + &(state->lenbits), state->work); + if (ret) { + strm->msg = (char *)"invalid literal/lengths set"; + state->mode = BAD; + break; + } + state->distcode = (code const FAR *)(state->next); + state->distbits = 6; + ret = inflate_table(DISTS, state->lens + state->nlen, state->ndist, + &(state->next), &(state->distbits), state->work); + if (ret) { + strm->msg = (char *)"invalid distances set"; + state->mode = BAD; + break; + } + Tracev((stderr, "inflate: codes ok\n")); + state->mode = LEN; + case LEN: + WATCHDOG_RESET(); + if (have >= 6 && left >= 258) { + RESTORE(); + inflate_fast(strm, out); + LOAD(); + break; + } + for (;;) { + this = state->lencode[BITS(state->lenbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if (this.op && (this.op & 0xf0) == 0) { + last = this; + for (;;) { + this = state->lencode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + this.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + } + DROPBITS(this.bits); + state->length = (unsigned)this.val; + if ((int)(this.op) == 0) { + Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? + "inflate: literal '%c'\n" : + "inflate: literal 0x%02x\n", this.val)); + state->mode = LIT; + break; + } + if (this.op & 32) { + Tracevv((stderr, "inflate: end of block\n")); + state->mode = TYPE; + break; + } + if (this.op & 64) { + strm->msg = (char *)"invalid literal/length code"; + state->mode = BAD; + break; + } + state->extra = (unsigned)(this.op) & 15; + state->mode = LENEXT; + case LENEXT: + if (state->extra) { + NEEDBITS(state->extra); + state->length += BITS(state->extra); + DROPBITS(state->extra); + } + Tracevv((stderr, "inflate: length %u\n", state->length)); + state->mode = DIST; + case DIST: + for (;;) { + this = state->distcode[BITS(state->distbits)]; + if ((unsigned)(this.bits) <= bits) break; + PULLBYTE(); + } + if ((this.op & 0xf0) == 0) { + last = this; + for (;;) { + this = state->distcode[last.val + + (BITS(last.bits + last.op) >> last.bits)]; + if ((unsigned)(last.bits + this.bits) <= bits) break; + PULLBYTE(); + } + DROPBITS(last.bits); + } + DROPBITS(this.bits); + if (this.op & 64) { + strm->msg = (char *)"invalid distance code"; + state->mode = BAD; + break; + } + state->offset = (unsigned)this.val; + state->extra = (unsigned)(this.op) & 15; + state->mode = DISTEXT; + case DISTEXT: + if (state->extra) { + NEEDBITS(state->extra); + state->offset += BITS(state->extra); + DROPBITS(state->extra); + } +#ifdef INFLATE_STRICT + if (state->offset > state->dmax) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } +#endif + if (state->offset > state->whave + out - left) { + strm->msg = (char *)"invalid distance too far back"; + state->mode = BAD; + break; + } + Tracevv((stderr, "inflate: distance %u\n", state->offset)); + state->mode = MATCH; + case MATCH: + if (left == 0) goto inf_leave; + copy = out - left; + if (state->offset > copy) { /* copy from window */ + copy = state->offset - copy; + if (copy > state->write) { + copy -= state->write; + from = state->window + (state->wsize - copy); + } + else + from = state->window + (state->write - copy); + if (copy > state->length) copy = state->length; + } + else { /* copy from output */ + from = put - state->offset; + copy = state->length; + } + if (copy > left) copy = left; + left -= copy; + state->length -= copy; + do { + *put++ = *from++; + } while (--copy); + if (state->length == 0) state->mode = LEN; + break; + case LIT: + if (left == 0) goto inf_leave; + *put++ = (unsigned char)(state->length); + left--; + state->mode = LEN; + break; + case CHECK: + if (state->wrap) { + NEEDBITS(32); + out -= left; + strm->total_out += out; + state->total += out; + if (out) + strm->adler = state->check = + UPDATE(state->check, put - out, out); + out = left; + if (( +#ifdef GUNZIP + state->flags ? hold : +#endif + REVERSE(hold)) != state->check) { + strm->msg = (char *)"incorrect data check"; + state->mode = BAD; + break; + } + INITBITS(); + Tracev((stderr, "inflate: check matches trailer\n")); + } +#ifdef GUNZIP + state->mode = LENGTH; + case LENGTH: + if (state->wrap && state->flags) { + NEEDBITS(32); + if (hold != (state->total & 0xffffffffUL)) { + strm->msg = (char *)"incorrect length check"; + state->mode = BAD; + break; + } + INITBITS(); + Tracev((stderr, "inflate: length matches trailer\n")); + } +#endif + state->mode = DONE; + case DONE: + ret = Z_STREAM_END; + goto inf_leave; + case BAD: + ret = Z_DATA_ERROR; + goto inf_leave; + case MEM: + return Z_MEM_ERROR; + case SYNC: + default: + return Z_STREAM_ERROR; + } + + /* + Return from inflate(), updating the total counts and the check value. + If there was no progress during the inflate() call, return a buffer + error. Call updatewindow() to create and/or update the window state. + Note: a memory error from inflate() is non-recoverable. + */ + inf_leave: + RESTORE(); + if (state->wsize || (state->mode < CHECK && out != strm->avail_out)) + if (updatewindow(strm, out)) { + state->mode = MEM; + return Z_MEM_ERROR; + } + in -= strm->avail_in; + out -= strm->avail_out; + strm->total_in += in; + strm->total_out += out; + state->total += out; + if (state->wrap && out) + strm->adler = state->check = + UPDATE(state->check, strm->next_out - out, out); + strm->data_type = state->bits + (state->last ? 64 : 0) + + (state->mode == TYPE ? 128 : 0); + if (((in == 0 && out == 0) || flush == Z_FINISH) && ret == Z_OK) + ret = Z_BUF_ERROR; + return ret; +} + +int ZEXPORT inflateEnd(strm) +z_streamp strm; +{ + struct inflate_state FAR *state; + if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) + return Z_STREAM_ERROR; + state = (struct inflate_state FAR *)strm->state; + if (state->window != Z_NULL) { + WATCHDOG_RESET(); + ZFREE(strm, state->window); + } + ZFREE(strm, strm->state); + strm->state = Z_NULL; + Tracev((stderr, "inflate: end\n")); + return Z_OK; +} |