libkern/zlib/zutil.c

   1 /*
   2  * Copyright (c) 2008-2016 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
 150 z_error(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
 161 zError(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
 177 zmemcpy(Bytef* dest, const Bytef* source, uInt  len)
 178 {
 179     if (len == 0) return;
 180     do {
 181         *dest++ = *source++; /* ??? to be unrolled */
 182     } while (--len != 0);
 183 }
 184
 185 int
 186 zmemcmp(const Bytef* s1, const Bytef* s2, uInt  len)
 187 {
 188     uInt j;
 189
 190     for (j = 0; j < len; j++) {
 191         if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
 192     }
 193     return 0;
 194 }
 195
 196 void
 197 zmemzero(Bytef* dest, uInt  len)
 198 {
 199     if (len == 0) return;
 200     do {
 201         *dest++ = 0;  /* ??? to be unrolled */
 202     } while (--len != 0);
 203 }
 204 #endif
 205
 206 #ifndef NO_ZCFUNCS
 207
 208 #ifdef SYS16BIT
 209
 210 #ifdef __TURBOC__
 211 /* Turbo C in 16-bit mode */
 212
 213 #  define MY_ZCALLOC
 214
 215 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
 216  * and farmalloc(64K) returns a pointer with an offset of 8, so we
 217  * must fix the pointer. Warning: the pointer must be put back to its
 218  * original form in order to free it, use zcfree().
 219  */
 220
 221 #define MAX_PTR 10
 222 /* 10*64K = 640K */
 223
 224 local int next_ptr = 0;
 225
 226 typedef struct ptr_table_s {
 227     voidpf org_ptr;
 228     voidpf new_ptr;
 229 } ptr_table;
 230
 231 local ptr_table table[MAX_PTR];
 232 /* This table is used to remember the original form of pointers
 233  * to large buffers (64K). Such pointers are normalized with a zero offset.
 234  * Since MSDOS is not a preemptive multitasking OS, this table is not
 235  * protected from concurrent access. This hack doesn't work anyway on
 236  * a protected system like OS/2. Use Microsoft C instead.
 237  */
 238
 239 voidpf
 240 zcalloc(voidpf opaque, unsigned items, unsigned size)
 241 {
 242     voidpf buf = opaque; /* just to make some compilers happy */
 243     ulg bsize = (ulg)items*size;
 244
 245     /* If we allocate less than 65520 bytes, we assume that farmalloc
 246      * will return a usable pointer which doesn't have to be normalized.
 247      */
 248     if (bsize < 65520L) {
 249         buf = farmalloc(bsize);
 250         if (*(ush*)&buf != 0) return buf;
 251     } else {
 252         buf = farmalloc(bsize + 16L);
 253     }
 254     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
 255     table[next_ptr].org_ptr = buf;
 256
 257     /* Normalize the pointer to seg:0 */
 258     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
 259     *(ush*)&buf = 0;
 260     table[next_ptr++].new_ptr = buf;
 261     return buf;
 262 }
 263
 264 void
 265 zcfree(voidpf opaque, voidpf ptr)
 266 {
 267     int n;
 268     if (*(ush*)&ptr != 0) { /* object < 64K */
 269         farfree(ptr);
 270         return;
 271     }
 272     /* Find the original pointer */
 273     for (n = 0; n < next_ptr; n++) {
 274         if (ptr != table[n].new_ptr) continue;
 275
 276         farfree(table[n].org_ptr);
 277         while (++n < next_ptr) {
 278             table[n-1] = table[n];
 279         }
 280         next_ptr--;
 281         return;
 282     }
 283     ptr = opaque; /* just to make some compilers happy */
 284     Assert(0, "zcfree: ptr not found");
 285 }
 286
 287 #endif /* __TURBOC__ */
 288
 289
 290 #ifdef M_I86
 291 /* Microsoft C in 16-bit mode */
 292
 293 #  define MY_ZCALLOC
 294
 295 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
 296 #  define _halloc  halloc
 297 #  define _hfree   hfree
 298 #endif
 299
 300 voidpf
 301 zcalloc(voidpf opaque, unsigned items, unsigned size)
 302 {
 303     if (opaque) opaque = 0; /* to make compiler happy */
 304     return _halloc((long)items, size);
 305 }
 306
 307 void
 308 zcfree(voidpf opaque, voidpf ptr)
 309 {
 310     if (opaque) opaque = 0; /* to make compiler happy */
 311     _hfree(ptr);
 312 }
 313
 314 #endif /* M_I86 */
 315
 316 #endif /* SYS16BIT */
 317
 318
 319 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
 320
 321 #ifndef STDC
 322 extern voidp  malloc OF((uInt size));
 323 extern voidp  calloc OF((uInt items, uInt size));
 324 extern void   free   OF((voidpf ptr));
 325 #endif
 326
 327 voidpf
 328 zcalloc(voidpf opaque, unsigned items, unsigned size)
 329 {
 330     if (opaque) items += size - size; /* make compiler happy */
 331     if (sizeof(uInt) > 2) {
 332         /*
 333             to prevent use of uninitialized memory, malloc and bzero
 334         */
 335         voidpf  p = malloc(items * size);
 336         bzero(p, items * size);
 337         return p;
 338     } else
 339         return (voidpf)calloc(items, size);
 340 }
 341
 342 void
 343 zcfree(voidpf opaque, voidpf ptr)
 344 {
 345     free(ptr);
 346     if (opaque) return; /* make compiler happy */
 347 }
 348
 349 #endif /* MY_ZCALLOC */
 350
 351 #endif /* NO_CZFUNCS */