getgr_r.c raw

   1  #include "pwf.h"
   2  #include <pthread.h>
   3  
   4  #define FIX(x) (gr->gr_##x = gr->gr_##x-line+buf)
   5  
   6  static int getgr_r(const char *name, gid_t gid, struct group *gr, char *buf, size_t size, struct group **res)
   7  {
   8  	char *line = 0;
   9  	size_t len = 0;
  10  	char **mem = 0;
  11  	size_t nmem = 0;
  12  	int rv = 0;
  13  	size_t i;
  14  	int cs;
  15  
  16  	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
  17  
  18  	rv = __getgr_a(name, gid, gr, &line, &len, &mem, &nmem, res);
  19  	if (*res && size < len + (nmem+1)*sizeof(char *) + 32) {
  20  		*res = 0;
  21  		rv = ERANGE;
  22  	}
  23  	if (*res) {
  24  		buf += (16-(uintptr_t)buf)%16;
  25  		gr->gr_mem = (void *)buf;
  26  		buf += (nmem+1)*sizeof(char *);
  27  		memcpy(buf, line, len);
  28  		FIX(name);
  29  		FIX(passwd);
  30  		for (i=0; mem[i]; i++)
  31  			gr->gr_mem[i] = mem[i]-line+buf;
  32  		gr->gr_mem[i] = 0;
  33  	}
  34   	free(mem);
  35   	free(line);
  36  	pthread_setcancelstate(cs, 0);
  37  	if (rv) errno = rv;
  38  	return rv;
  39  }
  40  
  41  int getgrnam_r(const char *name, struct group *gr, char *buf, size_t size, struct group **res)
  42  {
  43  	return getgr_r(name, 0, gr, buf, size, res);
  44  }
  45  
  46  int getgrgid_r(gid_t gid, struct group *gr, char *buf, size_t size, struct group **res)
  47  {
  48  	return getgr_r(0, gid, gr, buf, size, res);
  49  }
  50