lib/libz/zopen.c

   1 /*
   2  * Public domain stdio wrapper for libz, written by Johan Danielsson.
   3  */
   4
   5 #include <sys/cdefs.h>
   6 #include <stdio.h>
   7 #include <zlib.h>
   8
   9 FILE *zopen(const char *fname, const char *mode);
  10 FILE *zdopen(int fd, const char *mode);
  11
  12 /* convert arguments */
  13 static int
  14 xgzread(void *cookie, char *data, int size)
  15 {
  16     return gzread(cookie, data, size);
  17 }
  18
  19 static int
  20 xgzwrite(void *cookie, const char *data, int size)
  21 {
  22     return gzwrite(cookie, (void*)data, size);
  23 }
  24
  25 static int
  26 xgzclose(void *cookie)
  27 {
  28     return gzclose(cookie);
  29 }
  30
  31 static fpos_t
  32 xgzseek(void *cookie,  fpos_t offset, int whence)
  33 {
  34         return gzseek(cookie, (z_off_t)offset, whence);
  35 }
  36
  37 FILE *
  38 zopen(const char *fname, const char *mode)
  39 {
  40     gzFile gz = gzopen(fname, mode);
  41     if(gz == NULL)
  42         return NULL;
  43
  44     if(*mode == 'r')
  45         return (funopen(gz, xgzread, NULL, xgzseek, xgzclose));
  46     else
  47         return (funopen(gz, NULL, xgzwrite, xgzseek, xgzclose));
  48 }
  49
  50 FILE *
  51 zdopen(int fd, const char *mode)
  52 {
  53         gzFile gz;
  54
  55         gz = gzdopen(fd, mode);
  56         if (gz == NULL)
  57                 return (NULL);
  58
  59         if (*mode == 'r')
  60                 return (funopen(gz, xgzread, NULL, xgzseek, xgzclose));
  61         else
  62                 return (funopen(gz, NULL, xgzwrite, xgzseek, xgzclose));
  63 }