/* zutil.c -- target dependent utility functions for the compression library | |
* Copyright (C) 1995-2002 Jean-loup Gailly. | |
* For conditions of distribution and use, see copyright notice in zlib.h | |
*/ | |
/* @(#) $Id$ */ | |
#include "zutil.h" | |
#ifndef STDC | |
extern void exit OF((int)); | |
#endif | |
#ifndef HAVE_MEMCPY | |
void zmemcpy(dest, source, len) | |
Bytef* dest; | |
const Bytef* source; | |
uInt len; | |
{ | |
if (len == 0) return; | |
do { | |
*dest++ = *source++; /* ??? to be unrolled */ | |
} while (--len != 0); | |
} | |
int zmemcmp(s1, s2, len) | |
const Bytef* s1; | |
const Bytef* s2; | |
uInt len; | |
{ | |
uInt j; | |
for (j = 0; j < len; j++) { | |
if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1; | |
} | |
return 0; | |
} | |
void zmemzero(dest, len) | |
Bytef* dest; | |
uInt len; | |
{ | |
if (len == 0) return; | |
do { | |
*dest++ = 0; /* ??? to be unrolled */ | |
} while (--len != 0); | |
} | |
#endif | |
#if defined( MSDOS ) && defined( __TURBOC__ ) && !defined( MY_ZCALLOC ) | |
#if (defined( __BORLANDC__) || !defined(SMALL_MEDIUM)) && !defined(__32BIT__) | |
/* Small and medium model in Turbo C are for now limited to near allocation | |
* with reduced MAX_WBITS and MAX_MEM_LEVEL | |
*/ | |
# define MY_ZCALLOC | |
/* Turbo C malloc() does not allow dynamic allocation of 64K bytes | |
* and farmalloc(64K) returns a pointer with an offset of 8, so we | |
* must fix the pointer. Warning: the pointer must be put back to its | |
* original form in order to free it, use zcfree(). | |
*/ | |
#define MAX_PTR 10 | |
/* 10*64K = 640K */ | |
local int next_ptr = 0; | |
typedef struct ptr_table_s { | |
voidpf org_ptr; | |
voidpf new_ptr; | |
} ptr_table; | |
local ptr_table table[MAX_PTR]; | |
/* This table is used to remember the original form of pointers | |
* to large buffers (64K). Such pointers are normalized with a zero offset. | |
* Since MSDOS is not a preemptive multitasking OS, this table is not | |
* protected from concurrent access. This hack doesn't work anyway on | |
* a protected system like OS/2. Use Microsoft C instead. | |
*/ | |
voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) | |
{ | |
voidpf buf = opaque; /* just to make some compilers happy */ | |
ulg bsize = (ulg)items*size; | |
/* If we allocate less than 65520 bytes, we assume that farmalloc | |
* will return a usable pointer which doesn't have to be normalized. | |
*/ | |
if (bsize < 65520L) { | |
buf = farmalloc(bsize); | |
if (*(ush*)&buf != 0) return buf; | |
} else { | |
buf = farmalloc(bsize + 16L); | |
} | |
if (buf == NULL || next_ptr >= MAX_PTR) return NULL; | |
table[next_ptr].org_ptr = buf; | |
/* Normalize the pointer to seg:0 */ | |
*((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4; | |
*(ush*)&buf = 0; | |
table[next_ptr++].new_ptr = buf; | |
return buf; | |
} | |
void zcfree (voidpf opaque, voidpf ptr) | |
{ | |
int n; | |
if (*(ush*)&ptr != 0) { /* object < 64K */ | |
farfree(ptr); | |
return; | |
} | |
/* Find the original pointer */ | |
for (n = 0; n < next_ptr; n++) { | |
if (ptr != table[n].new_ptr) continue; | |
farfree(table[n].org_ptr); | |
while (++n < next_ptr) { | |
table[n-1] = table[n]; | |
} | |
next_ptr--; | |
return; | |
} | |
ptr = opaque; /* just to make some compilers happy */ | |
Assert(0, "zcfree: ptr not found"); | |
} | |
#endif | |
#endif /* MSDOS && __TURBOC__ */ | |
#if defined(M_I86) && !defined(__32BIT__) && !defined( MY_ZCALLOC ) | |
/* Microsoft C in 16-bit mode */ | |
# define MY_ZCALLOC | |
#if (!defined(_MSC_VER) || (_MSC_VER <= 600)) | |
# define _halloc halloc | |
# define _hfree hfree | |
#endif | |
voidpf zcalloc (voidpf opaque, unsigned items, unsigned size) | |
{ | |
if (opaque) opaque = 0; /* to make compiler happy */ | |
return _halloc((long)items, size); | |
} | |
void zcfree (voidpf opaque, voidpf ptr) | |
{ | |
if (opaque) opaque = 0; /* to make compiler happy */ | |
_hfree(ptr); | |
} | |
#endif /* MSC */ | |
#ifndef MY_ZCALLOC /* Any system without a special alloc function */ | |
#ifndef STDC | |
extern voidp ft_scalloc OF((uInt items, uInt size)); | |
extern void ft_sfree OF((voidpf ptr)); | |
#endif | |
voidpf zcalloc (opaque, items, size) | |
voidpf opaque; | |
unsigned items; | |
unsigned size; | |
{ | |
if (opaque) items += size - size; /* make compiler happy */ | |
return (voidpf)ft_scalloc(items, size); | |
} | |
void zcfree (opaque, ptr) | |
voidpf opaque; | |
voidpf ptr; | |
{ | |
ft_sfree(ptr); | |
if (opaque) return; /* make compiler happy */ | |
} | |
#endif /* MY_ZCALLOC */ |