common/transformation_zlib.c

   1 #include <stdio.h>
   2 #include <config.h>
   3
   4 #ifdef HAVE_ZLIB
   5 #include <zlib.h>
   6 #endif /* HAVE_ZLIB */
   7
   8 #include "transformation.h"
   9
  10 /*
  11  * Initialize
  12  */
  13 static int
  14 zlib_initialize(Transformation *xform)
  15 {
  16         return 0;
  17 }
  18
  19 /*
  20  * Shut down.
  21  */
  22 static int
  23 zlib_shutdown(Transformation *xform)
  24 {
  25         return 0;
  26 }
  27
  28 /*
  29  * Handle forks.
  30  */
  31 static int
  32 zlib_startNewTape(Transformation *xform, struct tapebuf *bin,
  33         unsigned long *destlen)
  34 {
  35         return 0;
  36 }
  37
  38 /*
  39  * Start slave process
  40  */
  41 static int
  42 zlib_startDiskIOProcess(Transformation *xform)
  43 {
  44         return 0;
  45 }
  46
  47 /*
  48  * End slave process
  49  */
  50 static int
  51 zlib_endDiskIOProcess(Transformation *xform)
  52 {
  53         if (xform != NULL) {
  54                 free(xform);
  55         }
  56
  57         return 0;
  58 }
  59
  60 struct req {
  61         ext2_loff_t dblk;
  62         int count;
  63 };
  64
  65 /*
  66  * Compress a buffer.
  67  */
  68 static int
  69 zlib_compress(Transformation *xform, struct tapebuf *tpbin,
  70                 unsigned long *destlen, const char *src, int srclen)
  71 {
  72 #ifdef HAVE_ZLIB
  73         int compresult;
  74         compresult = compress2(tpbin->buf, destlen, src, srclen, xform->state.zlib.complvl);
  75         return compresult == Z_OK ? 1 : 0;
  76 #else
  77         return 1;
  78 #endif /* HAVE_ZLIB */
  79 }
  80
  81 /*
  82  * Decompress a buffer.
  83  */
  84 static int
  85 zlib_decompress(Transformation *xform, struct tapebuf *tpbin,
  86         unsigned long *destlen, const char *src, int srclen, char **reason)
  87 {
  88 #ifdef HAVE_ZLIB
  89         int cresult;
  90         cresult = uncompress(tpbin->buf, destlen, src, srclen);
  91         switch (cresult) {
  92                 case Z_OK:
  93                         *reason = "";
  94                         break;
  95                 case Z_MEM_ERROR:
  96                         *reason = "not enough memory";
  97                         break;
  98                 case Z_BUF_ERROR:
  99                         *reason = "buffer too small";
 100                         break;
 101                 case Z_DATA_ERROR:
 102                         *reason = "data error";
 103                         break;
 104                 default:
 105                         *reason = "unknown";
 106         }
 107         return (cresult == Z_OK) ? 1 : 0;
 108 #else
 109         return 1;
 110 #endif /* HAVE_ZLIB */
 111 }
 112
 113
 114 /*
 115  * Factory
 116  */
 117 Transformation
 118 *transformation_zlib_factory(int enc, int complvl)
 119 {
 120         Transformation *t = (Transformation *) malloc(sizeof (Transformation));
 121
 122         t->enc = enc;
 123         t->state.zlib.complvl = complvl;
 124
 125         t->name = "zlib";
 126         t->mandatory = 0;
 127         t->initialize = &zlib_initialize;
 128         t->shutdown = &zlib_shutdown;
 129         t->startNewTape = &zlib_startNewTape;
 130         t->startDiskIOProcess = &zlib_startDiskIOProcess;
 131         t->endDiskIOProcess = &zlib_endDiskIOProcess;
 132         t->compress = &zlib_compress;
 133         t->decompress = &zlib_decompress;
 134
 135         return t;
 136 }