zutil.c

00001 /* zutil.c -- target dependent utility functions for the compression library
00002  * Copyright (C) 1995-2005, 2010, 2011, 2012 Jean-loup Gailly.
00003  * For conditions of distribution and use, see copyright notice in zlib.h
00004  */
00005 
00006 /* @(#) $Id$ */
00007 
00008 #include "zutil.h"
00009 #ifndef Z_SOLO
00010 #  include "gzguts.h"
00011 #endif
00012 
00013 #ifndef NO_DUMMY_DECL
00014 struct internal_state      {int dummy;}; /* for buggy compilers */
00015 #endif
00016 
00017 const char * const z_errmsg[10] = {
00018 "need dictionary",     /* Z_NEED_DICT       2  */
00019 "stream end",          /* Z_STREAM_END      1  */
00020 "",                    /* Z_OK              0  */
00021 "file error",          /* Z_ERRNO         (-1) */
00022 "stream error",        /* Z_STREAM_ERROR  (-2) */
00023 "data error",          /* Z_DATA_ERROR    (-3) */
00024 "insufficient memory", /* Z_MEM_ERROR     (-4) */
00025 "buffer error",        /* Z_BUF_ERROR     (-5) */
00026 "incompatible version",/* Z_VERSION_ERROR (-6) */
00027 ""};
00028 
00029 
00030 const char * ZEXPORT zlibVersion()
00031 {
00032     return ZLIB_VERSION;
00033 }
00034 
00035 uLong ZEXPORT zlibCompileFlags()
00036 {
00037     uLong flags;
00038 
00039     flags = 0;
00040     switch ((int)(sizeof(uInt))) {
00041     case 2:     break;
00042     case 4:     flags += 1;     break;
00043     case 8:     flags += 2;     break;
00044     default:    flags += 3;
00045     }
00046     switch ((int)(sizeof(uLong))) {
00047     case 2:     break;
00048     case 4:     flags += 1 << 2;        break;
00049     case 8:     flags += 2 << 2;        break;
00050     default:    flags += 3 << 2;
00051     }
00052     switch ((int)(sizeof(voidpf))) {
00053     case 2:     break;
00054     case 4:     flags += 1 << 4;        break;
00055     case 8:     flags += 2 << 4;        break;
00056     default:    flags += 3 << 4;
00057     }
00058     switch ((int)(sizeof(z_off_t))) {
00059     case 2:     break;
00060     case 4:     flags += 1 << 6;        break;
00061     case 8:     flags += 2 << 6;        break;
00062     default:    flags += 3 << 6;
00063     }
00064 #ifdef DEBUG
00065     flags += 1 << 8;
00066 #endif
00067 #if defined(ASMV) || defined(ASMINF)
00068     flags += 1 << 9;
00069 #endif
00070 #ifdef ZLIB_WINAPI
00071     flags += 1 << 10;
00072 #endif
00073 #ifdef BUILDFIXED
00074     flags += 1 << 12;
00075 #endif
00076 #ifdef DYNAMIC_CRC_TABLE
00077     flags += 1 << 13;
00078 #endif
00079 #ifdef NO_GZCOMPRESS
00080     flags += 1L << 16;
00081 #endif
00082 #ifdef NO_GZIP
00083     flags += 1L << 17;
00084 #endif
00085 #ifdef PKZIP_BUG_WORKAROUND
00086     flags += 1L << 20;
00087 #endif
00088 #ifdef FASTEST
00089     flags += 1L << 21;
00090 #endif
00091 #if defined(STDC) || defined(Z_HAVE_STDARG_H)
00092 #  ifdef NO_vsnprintf
00093     flags += 1L << 25;
00094 #    ifdef HAS_vsprintf_void
00095     flags += 1L << 26;
00096 #    endif
00097 #  else
00098 #    ifdef HAS_vsnprintf_void
00099     flags += 1L << 26;
00100 #    endif
00101 #  endif
00102 #else
00103     flags += 1L << 24;
00104 #  ifdef NO_snprintf
00105     flags += 1L << 25;
00106 #    ifdef HAS_sprintf_void
00107     flags += 1L << 26;
00108 #    endif
00109 #  else
00110 #    ifdef HAS_snprintf_void
00111     flags += 1L << 26;
00112 #    endif
00113 #  endif
00114 #endif
00115     return flags;
00116 }
00117 
00118 #ifdef DEBUG
00119 
00120 #  ifndef verbose
00121 #    define verbose 0
00122 #  endif
00123 int ZLIB_INTERNAL z_verbose = verbose;
00124 
00125 void ZLIB_INTERNAL z_error (m)
00126     char *m;
00127 {
00128     fprintf(stderr, "%s\n", m);
00129     exit(1);
00130 }
00131 #endif
00132 
00133 /* exported to allow conversion of error code to string for compress() and
00134  * uncompress()
00135  */
00136 const char * ZEXPORT zError(err)
00137     int err;
00138 {
00139     return ERR_MSG(err);
00140 }
00141 
00142 #if defined(_WIN32_WCE)
00143     /* The Microsoft C Run-Time Library for Windows CE doesn't have
00144      * errno.  We define it as a global variable to simplify porting.
00145      * Its value is always 0 and should not be used.
00146      */
00147     int errno = 0;
00148 #endif
00149 
00150 #ifndef HAVE_MEMCPY
00151 
00152 void ZLIB_INTERNAL zmemcpy(dest, source, len)
00153     Bytef* dest;
00154     const Bytef* source;
00155     uInt  len;
00156 {
00157     if (len == 0) return;
00158     do {
00159         *dest++ = *source++; /* ??? to be unrolled */
00160     } while (--len != 0);
00161 }
00162 
00163 int ZLIB_INTERNAL zmemcmp(s1, s2, len)
00164     const Bytef* s1;
00165     const Bytef* s2;
00166     uInt  len;
00167 {
00168     uInt j;
00169 
00170     for (j = 0; j < len; j++) {
00171         if (s1[j] != s2[j]) return 2*(s1[j] > s2[j])-1;
00172     }
00173     return 0;
00174 }
00175 
00176 void ZLIB_INTERNAL zmemzero(dest, len)
00177     Bytef* dest;
00178     uInt  len;
00179 {
00180     if (len == 0) return;
00181     do {
00182         *dest++ = 0;  /* ??? to be unrolled */
00183     } while (--len != 0);
00184 }
00185 #endif
00186 
00187 #ifndef Z_SOLO
00188 
00189 #ifdef SYS16BIT
00190 
00191 #ifdef __TURBOC__
00192 /* Turbo C in 16-bit mode */
00193 
00194 #  define MY_ZCALLOC
00195 
00196 /* Turbo C malloc() does not allow dynamic allocation of 64K bytes
00197  * and farmalloc(64K) returns a pointer with an offset of 8, so we
00198  * must fix the pointer. Warning: the pointer must be put back to its
00199  * original form in order to free it, use zcfree().
00200  */
00201 
00202 #define MAX_PTR 10
00203 /* 10*64K = 640K */
00204 
00205 local int next_ptr = 0;
00206 
00207 typedef struct ptr_table_s {
00208     voidpf org_ptr;
00209     voidpf new_ptr;
00210 } ptr_table;
00211 
00212 local ptr_table table[MAX_PTR];
00213 /* This table is used to remember the original form of pointers
00214  * to large buffers (64K). Such pointers are normalized with a zero offset.
00215  * Since MSDOS is not a preemptive multitasking OS, this table is not
00216  * protected from concurrent access. This hack doesn't work anyway on
00217  * a protected system like OS/2. Use Microsoft C instead.
00218  */
00219 
00220 voidpf ZLIB_INTERNAL zcalloc (voidpf opaque, unsigned items, unsigned size)
00221 {
00222     voidpf buf = opaque; /* just to make some compilers happy */
00223     ulg bsize = (ulg)items*size;
00224 
00225     /* If we allocate less than 65520 bytes, we assume that farmalloc
00226      * will return a usable pointer which doesn't have to be normalized.
00227      */
00228     if (bsize < 65520L) {
00229         buf = farmalloc(bsize);
00230         if (*(ush*)&buf != 0) return buf;
00231     } else {
00232         buf = farmalloc(bsize + 16L);
00233     }
00234     if (buf == NULL || next_ptr >= MAX_PTR) return NULL;
00235     table[next_ptr].org_ptr = buf;
00236 
00237     /* Normalize the pointer to seg:0 */
00238     *((ush*)&buf+1) += ((ush)((uch*)buf-0) + 15) >> 4;
00239     *(ush*)&buf = 0;
00240     table[next_ptr++].new_ptr = buf;
00241     return buf;
00242 }
00243 
00244 void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
00245 {
00246     int n;
00247     if (*(ush*)&ptr != 0) { /* object < 64K */
00248         farfree(ptr);
00249         return;
00250     }
00251     /* Find the original pointer */
00252     for (n = 0; n < next_ptr; n++) {
00253         if (ptr != table[n].new_ptr) continue;
00254 
00255         farfree(table[n].org_ptr);
00256         while (++n < next_ptr) {
00257             table[n-1] = table[n];
00258         }
00259         next_ptr--;
00260         return;
00261     }
00262     ptr = opaque; /* just to make some compilers happy */
00263     Assert(0, "zcfree: ptr not found");
00264 }
00265 
00266 #endif /* __TURBOC__ */
00267 
00268 
00269 #ifdef M_I86
00270 /* Microsoft C in 16-bit mode */
00271 
00272 #  define MY_ZCALLOC
00273 
00274 #if (!defined(_MSC_VER) || (_MSC_VER <= 600))
00275 #  define _halloc  halloc
00276 #  define _hfree   hfree
00277 #endif
00278 
00279 voidpf ZLIB_INTERNAL zcalloc (voidpf opaque, uInt items, uInt size)
00280 {
00281     if (opaque) opaque = 0; /* to make compiler happy */
00282     return _halloc((long)items, size);
00283 }
00284 
00285 void ZLIB_INTERNAL zcfree (voidpf opaque, voidpf ptr)
00286 {
00287     if (opaque) opaque = 0; /* to make compiler happy */
00288     _hfree(ptr);
00289 }
00290 
00291 #endif /* M_I86 */
00292 
00293 #endif /* SYS16BIT */
00294 
00295 
00296 #ifndef MY_ZCALLOC /* Any system without a special alloc function */
00297 
00298 #ifndef STDC
00299 extern voidp  malloc OF((uInt size));
00300 extern voidp  calloc OF((uInt items, uInt size));
00301 extern void   free   OF((voidpf ptr));
00302 #endif
00303 
00304 voidpf ZLIB_INTERNAL zcalloc (opaque, items, size)
00305     voidpf opaque;
00306     unsigned items;
00307     unsigned size;
00308 {
00309     if (opaque) items += size - size; /* make compiler happy */
00310     return sizeof(uInt) > 2 ? (voidpf)malloc(items * size) :
00311                               (voidpf)calloc(items, size);
00312 }
00313 
00314 void ZLIB_INTERNAL zcfree (opaque, ptr)
00315     voidpf opaque;
00316     voidpf ptr;
00317 {
00318     free(ptr);
00319     if (opaque) return; /* make compiler happy */
00320 }
00321 
00322 #endif /* MY_ZCALLOC */
00323 
00324 #endif /* !Z_SOLO */