libkern/zlib/zutil.c

   1 /*
   2  * Copyright (c) 2008 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /* zutil.c -- target dependent utility functions for the compression library
  29  * Copyright (C) 1995-2005 Jean-loup Gailly.
  30  * For conditions of distribution and use, see copyright notice in zlib.h
  31  */
  32
  33 /* @(#) $Id$ */
  34
  35 #include "zutil.h"
  36
  37 #ifndef NO_DUMMY_DECL
  38 struct internal_state      {int dummy;}; /* for buggy compilers */
  39 #endif
  40
  41 const char * const z_errmsg[10] = {
  42 "need dictionary",     /* Z_NEED_DICT       2  */
  43 "stream end",          /* Z_STREAM_END      1  */
  44 "",                    /* Z_OK              0  */
  45 "file error",          /* Z_ERRNO         (-1) */
  46 "stream error",        /* Z_STREAM_ERROR  (-2) */
  47 "data error",          /* Z_DATA_ERROR    (-3) */
  48 "insufficient memory", /* Z_MEM_ERROR     (-4) */
  49 "buffer error",        /* Z_BUF_ERROR     (-5) */
  50 "incompatible version",/* Z_VERSION_ERROR (-6) */
  51 ""};
  52
  53
  54 const char * ZEXPORT zlibVersion()
  55 {
  56     return ZLIB_VERSION;
  57 }
  58
  59 uLong ZEXPORT zlibCompileFlags()
  60 {
  61     uLong flags;
  62
  63     flags = 0;
  64     switch (sizeof(uInt)) {
  65     case 2:     break;
  66     case 4:     flags += 1;     break;
  67     case 8:     flags += 2;     break;
  68     default:    flags += 3;
  69     }
  70     switch (sizeof(uLong)) {
  71     case 2:     break;
  72     case 4:     flags += 1 << 2;        break;
  73     case 8:     flags += 2 << 2;        break;
  74     default:    flags += 3 << 2;
  75     }
  76     switch (sizeof(voidpf)) {
  77     case 2:     break;
  78     case 4:     flags += 1 << 4;        break;
  79     case 8:     flags += 2 << 4;        break;
  80     default:    flags += 3 << 4;
  81     }
  82     switch (sizeof(z_off_t)) {
  83     case 2:     break;
  84     case 4:     flags += 1 << 6;        break;
  85     case 8:     flags += 2 << 6;        break;
  86     default:    flags += 3 << 6;
  87     }
  88 #ifdef DEBUG
  89     flags += 1 << 8;
  90 #endif
  91 #if defined(ASMV) || defined(ASMINF)
  92     flags += 1 << 9;
  93 #endif
  94 #ifdef ZLIB_WINAPI
  95     flags += 1 << 10;
  96 #endif
  97 #ifdef BUILDFIXED
  98     flags += 1 << 12;
  99 #endif
 100 #ifdef DYNAMIC_CRC_TABLE
 101     flags += 1 << 13;
 102 #endif
 103 #ifdef NO_GZCOMPRESS
 104     flags += 1L << 16;
 105 #endif
 106 #ifdef NO_GZIP
 107     flags += 1L << 17;
 108 #endif
 109 #ifdef PKZIP_BUG_WORKAROUND
 110     flags += 1L << 20;
 111 #endif
 112 #ifdef FASTEST
 113     flags += 1L << 21;
 114 #endif
 115 #ifdef STDC
 116 #  ifdef NO_vsnprintf
 117         flags += 1L << 25;
 118 #    ifdef HAS_vsprintf_void
 119         flags += 1L << 26;
 120 #    endif
 121 #  else
 122 #    ifdef HAS_vsnprintf_void
 123         flags += 1L << 26;
 124 #    endif
 125 #  endif
 126 #else
 127         flags += 1L << 24;
 128 #  ifdef NO_snprintf
 129         flags += 1L << 25;
 130 #    ifdef HAS_sprintf_void
 131         flags += 1L << 26;
 132 #    endif
 133 #  else
 134 #    ifdef HAS_snprintf_void
 135         flags += 1L << 26;
 136 #    endif
 137 #  endif
 138 #endif
 139     return flags;
 140 }
 141
 142 #ifdef DEBUG
 143
 144 #  ifndef verbose
 145 #    define verbose 0
 146 #  endif
 147 int z_verbose = verbose;
 148
 149 void z_error (m)
 150     char *m;
 151 {
 152     fprintf(stderr, "%s\n", m);
 153     exit(1);
 154 }
 155 #endif
 156
 157 /* exported to allow conversion of error code to string for compress() and
 158  * uncompress()
 159  */
 160 const char * ZEXPORT zError(err)
 161     int err;
 162 {
 163     return ERR_MSG(err);
 164 }
 165
 166 #if defined(_WIN32_WCE)
 167     /* The Microsoft C Run-Time Library for Windows CE doesn't have
 168      * errno.  We define it as a global variable to simplify porting.
 169      * Its value is always 0 and should not be used.
 170      */
 171     int errno = 0;
 172 #endif
 173
 174 #ifndef HAVE_MEMCPY
 175
 176 void zmemcpy(dest, source, len)
 177     Bytef* dest;
 178     const Bytef* source;
 179     uInt  len;
 180 {
 181     if (len == 0) return;
 182     do {
 183         *dest++ = *source++; /* ??? to be unrolled */
 184     } while (--len != 0);
 185 }
 186
 187 int zmemcmp(s1, s2, len)
 188     const Bytef* s1;
 189     const Bytef* s2;
 190     uInt  len;
 191 {
 192     uInt j;
 193
 194     for (j = 0; j < len; j++) {
 195         if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
 196     }
 197     return 0;
 198 }
 199
 200 void zmemzero(dest, len)
 201     Bytef* dest;
 202     uInt  len;
 203 {
 204     if (len == 0) return;
 205     do {
 206         *dest++ = 0;  /* ??? to be unrolled */
 207     } while (--len != 0);
 208 }
 209 #endif
 210
 211 #ifndef NO_ZCFUNCS
 212
 213 #ifdef SYS16BIT
 214
 215 #ifdef __TURBOC__
 216 /* Turbo C in 16-bit mode */
 217
 218 #  define MY_ZCALLOC
 219
 220 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
 221  * and farmalloc(64K) returns a pointer with an offset of 8, so we
 222  * must fix the pointer. Warning: the pointer must be put back to its
 223  * original form in order to free it, use zcfree().
 224  */
 225
 226 #define MAX_PTR 10
 227 /* 10*64K = 640K */
 228
 229 local int next_ptr = 0;
 230
 231 typedef struct ptr_table_s {
 232     voidpf org_ptr;
 233     voidpf new_ptr;
 234 } ptr_table;
 235
 236 local ptr_table table[MAX_PTR];
 237 /* This table is used to remember the original form of pointers
 238  * to large buffers (64K). Such pointers are normalized with a zero offset.
 239  * Since MSDOS is not a preemptive multitasking OS, this table is not
 240  * protected from concurrent access. This hack doesn't work anyway on
 241  * a protected system like OS/2. Use Microsoft C instead.
 242  */
 243
 244 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
 245 {
 246     voidpf buf = opaque; /* just to make some compilers happy */
 247     ulg bsize = (ulg)items*size;
 248
 249     /* If we allocate less than 65520 bytes, we assume that farmalloc
 250      * will return a usable pointer which doesn't have to be normalized.
 251      */
 252     if (bsize < 65520L) {
 253         buf = farmalloc(bsize);
 254         if (*(ush*)&buf != 0) return buf;
 255     } else {
 256         buf = farmalloc(bsize + 16L);
 257     }
 258     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
 259     table[next_ptr].org_ptr = buf;
 260
 261     /* Normalize the pointer to seg:0 */
 262     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
 263     *(ush*)&buf = 0;
 264     table[next_ptr++].new_ptr = buf;
 265     return buf;
 266 }
 267
 268 void  zcfree (voidpf opaque, voidpf ptr)
 269 {
 270     int n;
 271     if (*(ush*)&ptr != 0) { /* object < 64K */
 272         farfree(ptr);
 273         return;
 274     }
 275     /* Find the original pointer */
 276     for (n = 0; n < next_ptr; n++) {
 277         if (ptr != table[n].new_ptr) continue;
 278
 279         farfree(table[n].org_ptr);
 280         while (++n < next_ptr) {
 281             table[n-1] = table[n];
 282         }
 283         next_ptr--;
 284         return;
 285     }
 286     ptr = opaque; /* just to make some compilers happy */
 287     Assert(0, "zcfree: ptr not found");
 288 }
 289
 290 #endif /* __TURBOC__ */
 291
 292
 293 #ifdef M_I86
 294 /* Microsoft C in 16-bit mode */
 295
 296 #  define MY_ZCALLOC
 297
 298 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
 299 #  define _halloc  halloc
 300 #  define _hfree   hfree
 301 #endif
 302
 303 voidpf zcalloc (voidpf opaque, unsigned items, unsigned size)
 304 {
 305     if (opaque) opaque = 0; /* to make compiler happy */
 306     return _halloc((long)items, size);
 307 }
 308
 309 void  zcfree (voidpf opaque, voidpf ptr)
 310 {
 311     if (opaque) opaque = 0; /* to make compiler happy */
 312     _hfree(ptr);
 313 }
 314
 315 #endif /* M_I86 */
 316
 317 #endif /* SYS16BIT */
 318
 319
 320 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
 321
 322 #ifndef STDC
 323 extern voidp  malloc OF((uInt size));
 324 extern voidp  calloc OF((uInt items, uInt size));
 325 extern void   free   OF((voidpf ptr));
 326 #endif
 327
 328 voidpf zcalloc (opaque, items, size)
 329     voidpf opaque;
 330     unsigned items;
 331     unsigned size;
 332 {
 333     if (opaque) items += size - size; /* make compiler happy */
 334     if (sizeof(uInt) > 2) {
 335         /*
 336             to prevent use of uninitialized memory, malloc and bzero
 337         */
 338         voidpf  p = malloc(items * size);
 339         bzero(p, items * size);
 340         return p;
 341     } else
 342         return (voidpf)calloc(items, size);
 343 }
 344
 345 void  zcfree (opaque, ptr)
 346     voidpf opaque;
 347     voidpf ptr;
 348 {
 349     free(ptr);
 350     if (opaque) return; /* make compiler happy */
 351 }
 352
 353 #endif /* MY_ZCALLOC */
 354
 355 #endif /* NO_CZFUNCS */