com32/libutil/loadfile.c

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 2005 H. Peter Anvin - All Rights Reserved
   4  *
   5  *   This program is free software; you can redistribute it and/or modify
   6  *   it under the terms of the GNU General Public License as published by
   7  *   the Free Software Foundation, Inc., 53 Temple Place Ste 330,
   8  *   Boston MA 02111-1307, USA; either version 2 of the License, or
   9  *   (at your option) any later version; incorporated herein by reference.
  10  *
  11  * ----------------------------------------------------------------------- */
  12
  13 /*
  14  * loadfile.c
  15  *
  16  * Read the contents of a data file into a malloc'd buffer
  17  */
  18
  19 #include <stdio.h>
  20 #include <stdlib.h>
  21 #include <unistd.h>
  22 #include <string.h>
  23 #include <fcntl.h>
  24 #include <sys/stat.h>
  25
  26 #include "loadfile.h"
  27
  28 int loadfile(const char *filename, void **ptr, size_t *len)
  29 {
  30   int fd;
  31   struct stat st;
  32   void *data;
  33   FILE *f;
  34   size_t xlen;
  35
  36   fd = open(filename, O_RDONLY);
  37   if ( fd < 0 )
  38     return -1;
  39
  40   f = fdopen(fd, "rb");
  41   if ( !f ) {
  42     close(fd);
  43     return -1;
  44   }
  45
  46   if ( fstat(fd, &st) )
  47     goto err_fclose;
  48
  49   *len = st.st_size;
  50   xlen = (st.st_size + LOADFILE_ZERO_PAD-1) & ~(LOADFILE_ZERO_PAD-1);
  51
  52   *ptr = data = malloc(xlen);
  53   if ( !data )
  54     goto err_fclose;
  55
  56   if ( (off_t)fread(data, 1, st.st_size, f) != st.st_size )
  57     goto err_free;
  58
  59   memset((char *)data + st.st_size, 0, xlen-st.st_size);
  60
  61   fclose(f);
  62   return 0;
  63
  64  err_free:
  65   free(data);
  66  err_fclose:
  67   fclose(f);
  68   return -1;
  69 }