readlink: uClibc supports automatic allocation too now

[oweals/busybox.git] / libbb / xreadlink.c

diff --git a/libbb/xreadlink.c b/libbb/xreadlink.c
index 0b961b6f90765895f927bd85ea8bf11667727006..0bdf394da278f71f78fa5d27c9cf494e1e9fd70a 100644 (file)
--- a/libbb/xreadlink.c
+++ b/libbb/xreadlink.c
@@ -1,7 +1,9 @@
 /* vi: set sw=4 ts=4: */
 /*
- *  xreadlink.c - safe implementation of readlink.
- *  Returns a NULL on failure...
+ * xreadlink.c - safe implementation of readlink.
+ * Returns a NULL on failure...
+ *
+ * Licensed under GPLv2, see file LICENSE in this source tree.
  */
 
 #include "libbb.h"
@@ -10,7 +12,7 @@
  * NOTE: This function returns a malloced char* that you will have to free
  * yourself.
  */
-char *xmalloc_readlink(const char *path)
+char* FAST_FUNC xmalloc_readlink(const char *path)
 {
        enum { GROWBY = 80 }; /* how large we will grow strings by */
 
@@ -42,7 +44,7 @@ char *xmalloc_readlink(const char *path)
  * those at the tail.
  * A malloced char* is returned, which must be freed by the caller.
  */
-char *xmalloc_follow_symlinks(const char *path)
+char* FAST_FUNC xmalloc_follow_symlinks(const char *path)
 {
        char *buf;
        char *lpc;
@@ -84,28 +86,31 @@ char *xmalloc_follow_symlinks(const char *path)
        }
 }
 
-char *xmalloc_readlink_or_warn(const char *path)
+char* FAST_FUNC xmalloc_readlink_or_warn(const char *path)
 {
        char *buf = xmalloc_readlink(path);
        if (!buf) {
                /* EINVAL => "file: Invalid argument" => puzzled user */
-               bb_error_msg("%s: cannot read link (not a symlink?)", path);
+               const char *errmsg = "not a symlink";
+               int err = errno;
+               if (err != EINVAL)
+                       errmsg = strerror(err);
+               bb_error_msg("%s: cannot read link: %s", path, errmsg);
        }
        return buf;
 }
 
-/* UNUSED */
-#if 0
-char *xmalloc_realpath(const char *path)
+char* FAST_FUNC xmalloc_realpath(const char *path)
 {
-#if defined(__GLIBC__) && !defined(__UCLIBC__)
+#if defined(__GLIBC__) || \
+    (defined(__UCLIBC__) && UCLIBC_VERSION >= KERNEL_VERSION(0, 9, 31))
        /* glibc provides a non-standard extension */
+       /* new: POSIX.1-2008 specifies this behavior as well */
        return realpath(path, NULL);
 #else
        char buf[PATH_MAX+1];
 
-       /* on error returns NULL (xstrdup(NULL) ==NULL) */
+       /* on error returns NULL (xstrdup(NULL) == NULL) */
        return xstrdup(realpath(path, buf));
 #endif
 }
-#endif