support/zlib_macros.c

   1 /*
   2  * Helper routines to use Zlib
   3  *
   4  * Author:
   5  *   Christopher Lahey (clahey@ximian.co)
   6  *
   7  * (C) 2004 Novell, Inc.
   8  */
   9 #include <config.h>
  10 #if defined (HAVE_ZLIB)
  11 #include <zlib.h>
  12 #else
  13 #include "zlib.h"
  14 #endif
  15
  16 #include <stdlib.h>
  17
  18 z_stream *
  19 create_z_stream(int compress, unsigned char gzip)
  20 {
  21         z_stream *z;
  22         int retval;
  23
  24 #if !defined(ZLIB_VERNUM) || (ZLIB_VERNUM < 0x1204)
  25         /* Older versions of zlib do not support raw deflate or gzip */
  26         return NULL;
  27 #endif
  28
  29         z = malloc (sizeof (z_stream));
  30         z->next_in = Z_NULL;
  31         z->avail_in = 0;
  32         z->next_out = Z_NULL;
  33         z->avail_out = 0;
  34         z->zalloc = Z_NULL;
  35         z->zfree = Z_NULL;
  36         z->opaque = NULL;
  37         if (compress) {
  38                 retval = deflateInit2 (z, Z_DEFAULT_COMPRESSION, Z_DEFLATED, gzip ? 31 : -15, 8, Z_DEFAULT_STRATEGY);
  39         } else {
  40                 retval = inflateInit2 (z, gzip ? 31 : -15);
  41         }
  42
  43         if (retval == Z_OK)
  44                 return z;
  45
  46         free (z);
  47         return NULL;
  48 }
  49
  50 void
  51 free_z_stream(z_stream *z, int compress)
  52 {
  53         if (compress) {
  54                 deflateEnd (z);
  55         } else {
  56                 inflateEnd (z);
  57         }
  58         free (z);
  59 }
  60
  61 void
  62 z_stream_set_next_in(z_stream *z, unsigned char *next_in)
  63 {
  64         z->next_in = next_in;
  65 }
  66
  67 void
  68 z_stream_set_avail_in(z_stream *z, int avail_in)
  69 {
  70         z->avail_in = avail_in;
  71 }
  72
  73 int
  74 z_stream_get_avail_in(z_stream *z)
  75 {
  76         return z->avail_in;
  77 }
  78
  79 void
  80 z_stream_set_next_out(z_stream *z, unsigned char *next_out)
  81 {
  82         z->next_out = next_out;
  83 }
  84
  85 void
  86 z_stream_set_avail_out(z_stream *z, int avail_out)
  87 {
  88         z->avail_out = avail_out;
  89 }
  90
  91 int
  92 z_stream_deflate (z_stream *z, int flush, unsigned char *next_out, int *avail_out)
  93 {
  94         int ret_val;
  95
  96         z->next_out = next_out;
  97         z->avail_out = *avail_out;
  98
  99         ret_val = deflate (z, flush);
 100
 101         *avail_out = z->avail_out;
 102
 103         return ret_val;
 104 }
 105
 106 int
 107 z_stream_inflate (z_stream *z, int *avail_out)
 108 {
 109         int ret_val;
 110
 111         z->avail_out = *avail_out;
 112
 113         ret_val = inflate (z, Z_NO_FLUSH);
 114
 115         *avail_out = z->avail_out;
 116
 117         return ret_val;
 118 }