28355a36da
make xreadlink() return NULL on failure, and make sure everyone uses the interface correctly. -Erik
38 lines
756 B
C
38 lines
756 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) {
|
|
perror_msg("%s:%s", applet_name, path);
|
|
return NULL;
|
|
}
|
|
}
|
|
while (bufsize < readsize + 1);
|
|
|
|
buf[readsize] = '\0';
|
|
|
|
return buf;
|
|
}
|
|
|