usr/src/boot/lib/libz/zopen.c

   1 /*
   2  * Public domain stdio wrapper for libz, written by Johan Danielsson.
   3  */
   4
   5 #include <sys/cdefs.h>
   6 __FBSDID("$FreeBSD$");
   7
   8 #include <stdio.h>
   9 #include <zlib.h>
  10
  11 FILE *zopen(const char *fname, const char *mode);
  12
  13 /* convert arguments */
  14 static int
  15 xgzread(void *cookie, char *data, int size)
  16 {
  17     return gzread(cookie, data, size);
  18 }
  19
  20 static int
  21 xgzwrite(void *cookie, const char *data, int size)
  22 {
  23     return gzwrite(cookie, (void*)data, size);
  24 }
  25
  26 static int
  27 xgzclose(void *cookie)
  28 {
  29     return gzclose(cookie);
  30 }
  31
  32 static fpos_t
  33 xgzseek(void *cookie,  fpos_t offset, int whence)
  34 {
  35         return gzseek(cookie, (z_off_t)offset, whence);
  36 }
  37
  38 FILE *
  39 zopen(const char *fname, const char *mode)
  40 {
  41     gzFile gz = gzopen(fname, mode);
  42     if(gz == NULL)
  43         return NULL;
  44
  45     if(*mode == 'r')
  46         return (funopen(gz, xgzread, NULL, xgzseek, xgzclose));
  47     else
  48         return (funopen(gz, NULL, xgzwrite, xgzseek, xgzclose));
  49 }