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zutil.c revision 1.2 
      1 /*	$NetBSD: zutil.c,v 1.2 2006/01/16 17:02:29 christos Exp $	*/
      2 
      3 /* zutil.c -- target dependent utility functions for the compression library
      4  * Copyright (C) 1995-2005 Jean-loup Gailly.
      5  * For conditions of distribution and use, see copyright notice in zlib.h
      6  */
      7 
      8 /* @(#) Id */
      9 
     10 #include "zutil.h"
     11 
     12 #ifndef NO_DUMMY_DECL
     13 struct internal_state      {int dummy;}; /* for buggy compilers */
     14 #endif
     15 
     16 const char * const z_errmsg[10] = {
     17 "need dictionary",     /* Z_NEED_DICT       2  */
     18 "stream end",          /* Z_STREAM_END      1  */
     19 "",                    /* Z_OK              0  */
     20 "file error",          /* Z_ERRNO         (-1) */
     21 "stream error",        /* Z_STREAM_ERROR  (-2) */
     22 "data error",          /* Z_DATA_ERROR    (-3) */
     23 "insufficient memory", /* Z_MEM_ERROR     (-4) */
     24 "buffer error",        /* Z_BUF_ERROR     (-5) */
     25 "incompatible version",/* Z_VERSION_ERROR (-6) */
     26 ""};
     27 
     28 
     29 const char * ZEXPORT zlibVersion()
     30 {
     31     return ZLIB_VERSION;
     32 }
     33 
     34 uLong ZEXPORT zlibCompileFlags()
     35 {
     36     uLong flags;
     37 
     38     flags = 0;
     39     switch (sizeof(uInt)) {
     40     case 2:     break;
     41     case 4:     flags += 1;     break;
     42     case 8:     flags += 2;     break;
     43     default:    flags += 3;
     44     }
     45     switch (sizeof(uLong)) {
     46     case 2:     break;
     47     case 4:     flags += 1 << 2;        break;
     48     case 8:     flags += 2 << 2;        break;
     49     default:    flags += 3 << 2;
     50     }
     51     switch (sizeof(voidpf)) {
     52     case 2:     break;
     53     case 4:     flags += 1 << 4;        break;
     54     case 8:     flags += 2 << 4;        break;
     55     default:    flags += 3 << 4;
     56     }
     57     switch (sizeof(z_off_t)) {
     58     case 2:     break;
     59     case 4:     flags += 1 << 6;        break;
     60     case 8:     flags += 2 << 6;        break;
     61     default:    flags += 3 << 6;
     62     }
     63 #ifdef ZLIB_DEBUG
     64     flags += 1 << 8;
     65 #endif
     66 #if defined(ASMV) || defined(ASMINF)
     67     flags += 1 << 9;
     68 #endif
     69 #ifdef ZLIB_WINAPI
     70     flags += 1 << 10;
     71 #endif
     72 #ifdef BUILDFIXED
     73     flags += 1 << 12;
     74 #endif
     75 #ifdef DYNAMIC_CRC_TABLE
     76     flags += 1 << 13;
     77 #endif
     78 #ifdef NO_GZCOMPRESS
     79     flags += 1L << 16;
     80 #endif
     81 #ifdef NO_GZIP
     82     flags += 1L << 17;
     83 #endif
     84 #ifdef PKZIP_BUG_WORKAROUND
     85     flags += 1L << 20;
     86 #endif
     87 #ifdef FASTEST
     88     flags += 1L << 21;
     89 #endif
     90 #ifdef STDC
     91 #  ifdef NO_vsnprintf
     92         flags += 1L << 25;
     93 #    ifdef HAS_vsprintf_void
     94         flags += 1L << 26;
     95 #    endif
     96 #  else
     97 #    ifdef HAS_vsnprintf_void
     98         flags += 1L << 26;
     99 #    endif
    100 #  endif
    101 #else
    102         flags += 1L << 24;
    103 #  ifdef NO_snprintf
    104         flags += 1L << 25;
    105 #    ifdef HAS_sprintf_void
    106         flags += 1L << 26;
    107 #    endif
    108 #  else
    109 #    ifdef HAS_snprintf_void
    110         flags += 1L << 26;
    111 #    endif
    112 #  endif
    113 #endif
    114     return flags;
    115 }
    116 
    117 #ifdef ZLIB_DEBUG
    118 
    119 #  ifndef verbose
    120 #    define verbose 0
    121 #  endif
    122 int z_verbose = verbose;
    123 
    124 void z_error (m)
    125     char *m;
    126 {
    127     fprintf(stderr, "%s\n", m);
    128     exit(1);
    129 }
    130 #endif
    131 
    132 /* exported to allow conversion of error code to string for compress() and
    133  * uncompress()
    134  */
    135 const char * ZEXPORT zError(err)
    136     int err;
    137 {
    138     return ERR_MSG(err);
    139 }
    140 
    141 #if defined(_WIN32_WCE)
    142     /* The Microsoft C Run-Time Library for Windows CE doesn't have
    143      * errno.  We define it as a global variable to simplify porting.
    144      * Its value is always 0 and should not be used.
    145      */
    146     int errno = 0;
    147 #endif
    148 
    149 #ifndef HAVE_MEMCPY
    150 
    151 void zmemcpy(dest, source, len)
    152     Bytef* dest;
    153     const Bytef* source;
    154     uInt  len;
    155 {
    156     if (len == 0) return;
    157     do {
    158         *dest++ = *source++; /* ??? to be unrolled */
    159     } while (--len != 0);
    160 }
    161 
    162 int zmemcmp(s1, s2, len)
    163     const Bytef* s1;
    164     const Bytef* s2;
    165     uInt  len;
    166 {
    167     uInt j;
    168 
    169     for (j = 0; j < len; j++) {
    170         if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
    171     }
    172     return 0;
    173 }
    174 
    175 void zmemzero(dest, len)
    176     Bytef* dest;
    177     uInt  len;
    178 {
    179     if (len == 0) return;
    180     do {
    181         *dest++ = 0;  /* ??? to be unrolled */
    182     } while (--len != 0);
    183 }
    184 #endif
    185 
    186 
    187 #ifdef SYS16BIT
    188 
    189 #ifdef __TURBOC__
    190 /* Turbo C in 16-bit mode */
    191 
    192 #  define MY_ZCALLOC
    193 
    194 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
    195  * and farmalloc(64K) returns a pointer with an offset of 8, so we
    196  * must fix the pointer. Warning: the pointer must be put back to its
    197  * original form in order to free it, use zcfree().
    198  */
    199 
    200 #define MAX_PTR 10
    201 /* 10*64K = 640K */
    202 
    203 local int next_ptr = 0;
    204 
    205 typedef struct ptr_table_s {
    206     voidpf org_ptr;
    207     voidpf new_ptr;
    208 } ptr_table;
    209 
    210 local ptr_table table[MAX_PTR];
    211 /* This table is used to remember the original form of pointers
    212  * to large buffers (64K). Such pointers are normalized with a zero offset.
    213  * Since MSDOS is not a preemptive multitasking OS, this table is not
    214  * protected from concurrent access. This hack doesn't work anyway on
    215  * a protected system like OS/2. Use Microsoft C instead.
    216  */
    217 
    218 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
    219 {
    220     voidpf buf = opaque; /* just to make some compilers happy */
    221     ulg bsize = (ulg)items*size;
    222 
    223     /* If we allocate less than 65520 bytes, we assume that farmalloc
    224      * will return a usable pointer which doesn't have to be normalized.
    225      */
    226     if (bsize < 65520L) {
    227         buf = farmalloc(bsize);
    228         if (*(ush*)&buf != 0) return buf;
    229     } else {
    230         buf = farmalloc(bsize + 16L);
    231     }
    232     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
    233     table[next_ptr].org_ptr = buf;
    234 
    235     /* Normalize the pointer to seg:0 */
    236     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
    237     *(ush*)&buf = 0;
    238     table[next_ptr++].new_ptr = buf;
    239     return buf;
    240 }
    241 
    242 void  zcfree (voidpf opaque, voidpf ptr)
    243 {
    244     int n;
    245     if (*(ush*)&ptr != 0) { /* object < 64K */
    246         farfree(ptr);
    247         return;
    248     }
    249     /* Find the original pointer */
    250     for (n = 0; n < next_ptr; n++) {
    251         if (ptr != table[n].new_ptr) continue;
    252 
    253         farfree(table[n].org_ptr);
    254         while (++n < next_ptr) {
    255             table[n-1] = table[n];
    256         }
    257         next_ptr--;
    258         return;
    259     }
    260     ptr = opaque; /* just to make some compilers happy */
    261     Assert(0, "zcfree: ptr not found");
    262 }
    263 
    264 #endif /* __TURBOC__ */
    265 
    266 
    267 #ifdef M_I86
    268 /* Microsoft C in 16-bit mode */
    269 
    270 #  define MY_ZCALLOC
    271 
    272 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
    273 #  define _halloc  halloc
    274 #  define _hfree   hfree
    275 #endif
    276 
    277 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
    278 {
    279     if (opaque) opaque = 0; /* to make compiler happy */
    280     return _halloc((long)items, size);
    281 }
    282 
    283 void  zcfree (voidpf opaque, voidpf ptr)
    284 {
    285     if (opaque) opaque = 0; /* to make compiler happy */
    286     _hfree(ptr);
    287 }
    288 
    289 #endif /* M_I86 */
    290 
    291 #endif /* SYS16BIT */
    292 
    293 
    294 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
    295 
    296 #ifndef STDC
    297 extern voidp  malloc OF((uInt size));
    298 extern voidp  calloc OF((uInt items, uInt size));
    299 extern void   free   OF((voidpf ptr));
    300 #endif
    301 
    302 voidpf zcalloc (opaque, items, size)
    303     voidpf opaque;
    304     unsigned items;
    305     unsigned size;
    306 {
    307     if (opaque) items += size - size; /* make compiler happy */
    308     return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
    309                               (voidpf)calloc(items, size);
    310 }
    311 
    312 void  zcfree (opaque, ptr)
    313     voidpf opaque;
    314     voidpf ptr;
    315 {
    316     free(ptr);
    317     if (opaque) return; /* make compiler happy */
    318 }
    319 
    320 #endif /* MY_ZCALLOC */
    321