1 files changed, 37 insertions, 0 deletions

diff --git a/busybox/libbb/xreadlink.c b/busybox/libbb/xreadlink.c
new file mode 100644
index 000000000..49823fa7f
--- /dev/null
+++ b/busybox/libbb/xreadlink.c
@@ -0,0 +1,37 @@
+/*
+ *  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);
+                        free(buf);
+                        return NULL;
+                }
+        }
+        while (bufsize < readsize + 1);
+
+        buf[readsize] = '\0';
+
+        return buf;
+}