From ff2a6f1b3aefd413bcf31ea7a54597edfbde9adc Mon Sep 17 00:00:00 2001
From: Joel Rosdahl <joel@rosdahl.net>
Date: Sun, 1 Aug 2010 14:08:42 +0200
Subject: [PATCH] Add x_readlink() utility function

---
 ccache.h |  1 +
 util.c   | 26 ++++++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/ccache.h b/ccache.h
index f9aaf8798..3a650a740 100644
--- a/ccache.h
+++ b/ccache.h
@@ -123,6 +123,7 @@ void update_mtime(const char *path);
 void *x_fmmap(const char *fname, off_t *size, const char *errstr);
 int x_munmap(void *addr, size_t length);
 int x_rename(const char *oldpath, const char *newpath);
+char *x_readlink(const char *path);
 
 /* ------------------------------------------------------------------------- */
 /* stats.c */
diff --git a/util.c b/util.c
index 7fb7f5435..3bc554226 100644
--- a/util.c
+++ b/util.c
@@ -1114,3 +1114,29 @@ int x_rename(const char *oldpath, const char *newpath)
 #endif
 	return rename(oldpath, newpath);
 }
+
+/* Like readlink() but returns the string or NULL on failure. Caller frees. */
+char *
+x_readlink(const char *path)
+{
+	size_t maxlen;
+	ssize_t len;
+	char *buf;
+#ifdef PATH_MAX
+	maxlen = PATH_MAX;
+#elif defined(MAXPATHLEN)
+	maxlen = MAXPATHLEN;
+#elif defined(_PC_PATH_MAX)
+	maxlen = pathconf(path, _PC_PATH_MAX);
+#endif
+	if (maxlen < 4096) maxlen = 4096;
+
+	buf = x_malloc(maxlen);
+	len = readlink(path, buf, maxlen-1);
+	if (len == -1) {
+		free(buf);
+		return NULL;
+	}
+	buf[len] = 0;
+	return buf;
+}
-- 
2.47.3