hush/libbb/xreadlink.c

37 lines
714 B
C

/*
* xreadlink.c - safe implementation of readlink.
* Returns a NULL on failure...
*/
#include <stdio.h>
/*
* NOTE: This function returns a malloced char* that you will have to free
* yourself. You have been warned.
*/
#include <unistd.h>
#include "libbb.h"
extern char *xreadlink(const char *path)
{
static const int GROWBY = 80; /* how large we will grow strings by */
char *buf = NULL;
int bufsize = 0, readsize = 0;
do {
buf = xrealloc(buf, bufsize += GROWBY);
readsize = readlink(path, buf, bufsize); /* 1st try */
if (readsize == -1) {
bb_perror_msg("%s", path);
return NULL;
}
}
while (bufsize < readsize + 1);
buf[readsize] = '\0';
return buf;
}