Glassfish example source code file (zutil.c)

This example Glassfish source code file (zutil.c) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Glassfish tags/keywords

assert, bytef, bytef, max_ptr, my_zcalloc, my_zcalloc, null, of, of, stdc, stdc, z_data_error, z_stream_end, zexport

The Glassfish zutil.c source code

/* 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 
 */


#include "zutil.h"

struct internal_state      {int dummy;}; /* for buggy compilers */

#ifndef STDC
extern void exit OF((int));
#endif

const char *z_errmsg[10] = {
"need dictionary",     /* Z_NEED_DICT       2  */
"stream end",          /* Z_STREAM_END      1  */
"",                    /* Z_OK              0  */
"file error",          /* Z_ERRNO         (-1) */
"stream error",        /* Z_STREAM_ERROR  (-2) */
"data error",          /* Z_DATA_ERROR    (-3) */
"insufficient memory", /* Z_MEM_ERROR     (-4) */
"buffer error",        /* Z_BUF_ERROR     (-5) */
"incompatible version",/* Z_VERSION_ERROR (-6) */
""};


const char * ZEXPORT zlibVersion()
{
    return ZLIB_VERSION;
}

#ifdef DEBUG

#  ifndef verbose
#    define verbose 0
#  endif
int z_verbose = verbose;

void z_error (m)
    char *m;
{
    fprintf(stderr, "%s\n", m);
    exit(1);
}
#endif

/* exported to allow conversion of error code to string for compress() and
 * uncompress()
 */
const char * ZEXPORT zError(err)
    int err;
{
    return ERR_MSG(err);
}


#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

#ifdef __TURBOC__
#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 /* __TURBOC__ */


#if defined(M_I86) && !defined(__32BIT__)
/* 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  calloc OF((uInt items, uInt size));
extern void   free   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)calloc(items, size);
}

void  zcfree (opaque, ptr)
    voidpf opaque;
    voidpf ptr;
{
    free(ptr);
    if (opaque) return; /* make compiler happy */
}

#endif /* MY_ZCALLOC */