diff options
Diffstat (limited to 'zlib/inffast.c')
| -rw-r--r-- | zlib/inffast.c | 183 |
1 files changed, 0 insertions, 183 deletions
diff --git a/zlib/inffast.c b/zlib/inffast.c deleted file mode 100644 index aa7f1d4d2..000000000 --- a/zlib/inffast.c +++ /dev/null @@ -1,183 +0,0 @@ -/* inffast.c -- process literals and length/distance pairs fast - * Copyright (C) 1995-2002 Mark Adler - * For conditions of distribution and use, see copyright notice in zlib.h - */ - -#include "zutil.h" -#include "inftrees.h" -#include "infblock.h" -#include "infcodes.h" -#include "infutil.h" -#include "inffast.h" - -struct inflate_codes_state {int dummy;}; /* for buggy compilers */ - -/* simplify the use of the inflate_huft type with some defines */ -#define exop word.what.Exop -#define bits word.what.Bits - -/* macros for bit input with no checking and for returning unused bytes */ -#define GRABBITS(j) {while(k<(j)){b|=((uLong)NEXTBYTE)<<k;k+=8;}} -#define UNGRAB {c=z->avail_in-n;c=(k>>3)<c?k>>3:c;n+=c;p-=c;k-=c<<3;} - -/* Called with number of bytes left to write in window at least 258 - (the maximum string length) and number of input bytes available - at least ten. The ten bytes are six bytes for the longest length/ - distance pair plus four bytes for overloading the bit buffer. */ - -int inflate_fast(bl, bd, tl, td, s, z) -uInt bl, bd; -inflate_huft *tl; -inflate_huft *td; /* need separate declaration for Borland C++ */ -inflate_blocks_statef *s; -z_streamp z; -{ - inflate_huft *t; /* temporary pointer */ - uInt e; /* extra bits or operation */ - uLong b; /* bit buffer */ - uInt k; /* bits in bit buffer */ - Bytef *p; /* input data pointer */ - uInt n; /* bytes available there */ - Bytef *q; /* output window write pointer */ - uInt m; /* bytes to end of window or read pointer */ - uInt ml; /* mask for literal/length tree */ - uInt md; /* mask for distance tree */ - uInt c; /* bytes to copy */ - uInt d; /* distance back to copy from */ - Bytef *r; /* copy source pointer */ - - /* load input, output, bit values */ - LOAD - - /* initialize masks */ - ml = inflate_mask[bl]; - md = inflate_mask[bd]; - - /* do until not enough input or output space for fast loop */ - do { /* assume called with m >= 258 && n >= 10 */ - /* get literal/length code */ - GRABBITS(20) /* max bits for literal/length code */ - if ((e = (t = tl + ((uInt)b & ml))->exop) == 0) - { - DUMPBITS(t->bits) - Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? - "inflate: * literal '%c'\n" : - "inflate: * literal 0x%02x\n", t->base)); - *q++ = (Byte)t->base; - m--; - continue; - } - do { - DUMPBITS(t->bits) - if (e & 16) - { - /* get extra bits for length */ - e &= 15; - c = t->base + ((uInt)b & inflate_mask[e]); - DUMPBITS(e) - Tracevv((stderr, "inflate: * length %u\n", c)); - - /* decode distance base of block to copy */ - GRABBITS(15); /* max bits for distance code */ - e = (t = td + ((uInt)b & md))->exop; - do { - DUMPBITS(t->bits) - if (e & 16) - { - /* get extra bits to add to distance base */ - e &= 15; - GRABBITS(e) /* get extra bits (up to 13) */ - d = t->base + ((uInt)b & inflate_mask[e]); - DUMPBITS(e) - Tracevv((stderr, "inflate: * distance %u\n", d)); - - /* do the copy */ - m -= c; - r = q - d; - if (r < s->window) /* wrap if needed */ - { - do { - r += s->end - s->window; /* force pointer in window */ - } while (r < s->window); /* covers invalid distances */ - e = s->end - r; - if (c > e) - { - c -= e; /* wrapped copy */ - do { - *q++ = *r++; - } while (--e); - r = s->window; - do { - *q++ = *r++; - } while (--c); - } - else /* normal copy */ - { - *q++ = *r++; c--; - *q++ = *r++; c--; - do { - *q++ = *r++; - } while (--c); - } - } - else /* normal copy */ - { - *q++ = *r++; c--; - *q++ = *r++; c--; - do { - *q++ = *r++; - } while (--c); - } - break; - } - else if ((e & 64) == 0) - { - t += t->base; - e = (t += ((uInt)b & inflate_mask[e]))->exop; - } - else - { - z->msg = (char*)"invalid distance code"; - UNGRAB - UPDATE - return Z_DATA_ERROR; - } - } while (1); - break; - } - if ((e & 64) == 0) - { - t += t->base; - if ((e = (t += ((uInt)b & inflate_mask[e]))->exop) == 0) - { - DUMPBITS(t->bits) - Tracevv((stderr, t->base >= 0x20 && t->base < 0x7f ? - "inflate: * literal '%c'\n" : - "inflate: * literal 0x%02x\n", t->base)); - *q++ = (Byte)t->base; - m--; - break; - } - } - else if (e & 32) - { - Tracevv((stderr, "inflate: * end of block\n")); - UNGRAB - UPDATE - return Z_STREAM_END; - } - else - { - z->msg = (char*)"invalid literal/length code"; - UNGRAB - UPDATE - return Z_DATA_ERROR; - } - } while (1); - } while (m >= 258 && n >= 10); - - /* not enough input or output--restore pointers and return */ - UNGRAB - UPDATE - return Z_OK; -} |