diff options
Diffstat (limited to 'libpng/infback.c')
| -rw-r--r-- | libpng/infback.c | 623 |
1 files changed, 0 insertions, 623 deletions
diff --git a/libpng/infback.c b/libpng/infback.c deleted file mode 100644 index 455dbc9..0000000 --- a/libpng/infback.c +++ /dev/null @@ -1,623 +0,0 @@ -/* infback.c -- inflate using a call-back interface - * Copyright (C) 1995-2005 Mark Adler - * For conditions of distribution and use, see copyright notice in zlib.h - */ - -/* - This code is largely copied from inflate.c. Normally either infback.o or - inflate.o would be linked into an application--not both. The interface - with inffast.c is retained so that optimized assembler-coded versions of - inflate_fast() can be used with either inflate.c or infback.c. - */ - -#include "zutil.h" -#include "inftrees.h" -#include "inflate.h" -#include "inffast.h" - -/* function prototypes */ -local void fixedtables OF((struct inflate_state FAR *state)); - -/* - strm provides memory allocation functions in zalloc and zfree, or - Z_NULL to use the library memory allocation functions. - - windowBits is in the range 8..15, and window is a user-supplied - window and output buffer that is 2**windowBits bytes. - */ -int ZEXPORT inflateBackInit_(strm, windowBits, window, version, stream_size) -z_streamp strm; -int windowBits; -unsigned char FAR *window; -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 || window == Z_NULL || - windowBits < 8 || windowBits > 15) - 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; - state->dmax = 32768U; - state->wbits = windowBits; - state->wsize = 1U << windowBits; - state->window = window; - state->write = 0; - state->whave = 0; - return Z_OK; -} - -/* - Return state with length and distance decoding tables and index sizes set to - fixed code decoding. Normally this returns fixed tables from inffixed.h. - If BUILDFIXED is defined, then instead this routine builds the tables the - first time it's called, and returns those tables the first time and - thereafter. This reduces the size of the code by about 2K bytes, in - exchange for a little execution time. However, BUILDFIXED should not be - used for threaded applications, since the rewriting of the tables and virgin - may not be thread-safe. - */ -local void fixedtables(state) -struct inflate_state FAR *state; -{ -#ifdef BUILDFIXED - static int virgin = 1; - static code *lenfix, *distfix; - static code fixed[544]; - - /* build fixed huffman tables if first call (may not be thread safe) */ - if (virgin) { - unsigned sym, bits; - static code *next; - - /* literal/length table */ - sym = 0; - while (sym < 144) state->lens[sym++] = 8; - while (sym < 256) state->lens[sym++] = 9; - while (sym < 280) state->lens[sym++] = 7; - while (sym < 288) state->lens[sym++] = 8; - next = fixed; - lenfix = next; - bits = 9; - inflate_table(LENS, state->lens, 288, &(next), &(bits), state->work); - - /* distance table */ - sym = 0; - while (sym < 32) state->lens[sym++] = 5; - distfix = next; - bits = 5; - inflate_table(DISTS, state->lens, 32, &(next), &(bits), state->work); - - /* do this just once */ - virgin = 0; - } -#else /* !BUILDFIXED */ -# include "inffixed.h" -#endif /* BUILDFIXED */ - state->lencode = lenfix; - state->lenbits = 9; - state->distcode = distfix; - state->distbits = 5; -} - -/* Macros for inflateBack(): */ - -/* Load returned state from inflate_fast() */ -#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) - -/* Set state from registers for inflate_fast() */ -#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) - -/* Assure that some input is available. If input is requested, but denied, - then return a Z_BUF_ERROR from inflateBack(). */ -#define PULL() \ - do { \ - if (have == 0) { \ - have = in(in_desc, &next); \ - if (have == 0) { \ - next = Z_NULL; \ - ret = Z_BUF_ERROR; \ - goto inf_leave; \ - } \ - } \ - } while (0) - -/* Get a byte of input into the bit accumulator, or return from inflateBack() - with an error if there is no input available. */ -#define PULLBYTE() \ - do { \ - PULL(); \ - 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 inflateBack() with - an error. */ -#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) - -/* Assure that some output space is available, by writing out the window - if it's full. If the write fails, return from inflateBack() with a - Z_BUF_ERROR. */ -#define ROOM() \ - do { \ - if (left == 0) { \ - put = state->window; \ - left = state->wsize; \ - state->whave = left; \ - if (out(out_desc, put, left)) { \ - ret = Z_BUF_ERROR; \ - goto inf_leave; \ - } \ - } \ - } while (0) - -/* - strm provides the memory allocation functions and window buffer on input, - and provides information on the unused input on return. For Z_DATA_ERROR - returns, strm will also provide an error message. - - in() and out() are the call-back input and output functions. When - inflateBack() needs more input, it calls in(). When inflateBack() has - filled the window with output, or when it completes with data in the - window, it calls out() to write out the data. The application must not - change the provided input until in() is called again or inflateBack() - returns. The application must not change the window/output buffer until - inflateBack() returns. - - in() and out() are called with a descriptor parameter provided in the - inflateBack() call. This parameter can be a structure that provides the - information required to do the read or write, as well as accumulated - information on the input and output such as totals and check values. - - in() should return zero on failure. out() should return non-zero on - failure. If either in() or out() fails, than inflateBack() returns a - Z_BUF_ERROR. strm->next_in can be checked for Z_NULL to see whether it - was in() or out() that caused in the error. Otherwise, inflateBack() - returns Z_STREAM_END on success, Z_DATA_ERROR for an deflate format - error, or Z_MEM_ERROR if it could not allocate memory for the state. - inflateBack() can also return Z_STREAM_ERROR if the input parameters - are not correct, i.e. strm is Z_NULL or the state was not initialized. - */ -int ZEXPORT inflateBack(strm, in, in_desc, out, out_desc) -z_streamp strm; -in_func in; -void FAR *in_desc; -out_func out; -void FAR *out_desc; -{ - 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 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 */ - 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}; - - /* Check that the strm exists and that the state was initialized */ - if (strm == Z_NULL || strm->state == Z_NULL) - return Z_STREAM_ERROR; - state = (struct inflate_state FAR *)strm->state; - - /* Reset the state */ - strm->msg = Z_NULL; - state->mode = TYPE; - state->last = 0; - state->whave = 0; - next = strm->next_in; - have = next != Z_NULL ? strm->avail_in : 0; - hold = 0; - bits = 0; - put = state->window; - left = state->wsize; - - /* Inflate until end of block marked as last */ - for (;;) - switch (state->mode) { - case TYPE: - /* determine and dispatch block type */ - if (state->last) { - BYTEBITS(); - state->mode = DONE; - 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: - /* get and verify stored block length */ - 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(); - - /* copy stored block from input to output */ - while (state->length != 0) { - copy = state->length; - PULL(); - ROOM(); - if (copy > have) copy = have; - if (copy > left) copy = left; - zmemcpy(put, next, copy); - have -= copy; - next += copy; - left -= copy; - put += copy; - state->length -= copy; - } - Tracev((stderr, "inflate: stored end\n")); - state->mode = TYPE; - break; - - case TABLE: - /* get dynamic table entries descriptor */ - 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")); - - /* get code length code lengths (not a typo) */ - state->have = 0; - 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")); - - /* get length and distance code code lengths */ - state->have = 0; - 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 = (unsigned)(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: - /* use inflate_fast() if we have enough input and output */ - if (have >= 6 && left >= 258) { - RESTORE(); - if (state->whave < state->wsize) - state->whave = state->wsize - left; - inflate_fast(strm, state->wsize); - LOAD(); - break; - } - - /* get a literal, length, or end-of-block code */ - 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; - - /* process literal */ - if (this.op == 0) { - Tracevv((stderr, this.val >= 0x20 && this.val < 0x7f ? - "inflate: literal '%c'\n" : - "inflate: literal 0x%02x\n", this.val)); - ROOM(); - *put++ = (unsigned char)(state->length); - left--; - state->mode = LEN; - break; - } - - /* process end of block */ - if (this.op & 32) { - Tracevv((stderr, "inflate: end of block\n")); - state->mode = TYPE; - break; - } - - /* invalid code */ - if (this.op & 64) { - strm->msg = (char *)"invalid literal/length code"; - state->mode = BAD; - break; - } - - /* length code -- get extra bits, if any */ - state->extra = (unsigned)(this.op) & 15; - if (state->extra != 0) { - NEEDBITS(state->extra); - state->length += BITS(state->extra); - DROPBITS(state->extra); - } - Tracevv((stderr, "inflate: length %u\n", state->length)); - - /* get distance code */ - 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; - - /* get distance extra bits, if any */ - state->extra = (unsigned)(this.op) & 15; - if (state->extra != 0) { - NEEDBITS(state->extra); - state->offset += BITS(state->extra); - DROPBITS(state->extra); - } - if (state->offset > state->wsize - (state->whave < state->wsize ? - left : 0)) { - strm->msg = (char *)"invalid distance too far back"; - state->mode = BAD; - break; - } - Tracevv((stderr, "inflate: distance %u\n", state->offset)); - - /* copy match from window to output */ - do { - ROOM(); - copy = state->wsize - state->offset; - if (copy < left) { - from = put + copy; - copy = left - copy; - } - else { - from = put - state->offset; - copy = left; - } - if (copy > state->length) copy = state->length; - state->length -= copy; - left -= copy; - do { - *put++ = *from++; - } while (--copy); - } while (state->length != 0); - break; - - case DONE: - /* inflate stream terminated properly -- write leftover output */ - ret = Z_STREAM_END; - if (left < state->wsize) { - if (out(out_desc, state->window, state->wsize - left)) - ret = Z_BUF_ERROR; - } - goto inf_leave; - - case BAD: - ret = Z_DATA_ERROR; - goto inf_leave; - - default: /* can't happen, but makes compilers happy */ - ret = Z_STREAM_ERROR; - goto inf_leave; - } - - /* Return unused input */ - inf_leave: - strm->next_in = next; - strm->avail_in = have; - return ret; -} - -int ZEXPORT inflateBackEnd(strm) -z_streamp strm; -{ - if (strm == Z_NULL || strm->state == Z_NULL || strm->zfree == (free_func)0) - return Z_STREAM_ERROR; - ZFREE(strm, strm->state); - strm->state = Z_NULL; - Tracev((stderr, "inflate: end\n")); - return Z_OK; -} |