libext2fs: support operating systems that don't have strnlen()

Someone was trying to build e2fsprogs on MacOS 10.6.8, and ran into
build problems because MacOS didn't have strnlen() support until seven
years ago.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Jens Bauer <jens@plustv.dk>

diff --git a/lib/ext2fs/symlink.c b/lib/ext2fs/symlink.c
index 13bca6e99efed797d89dc4430423ac1d5c88c236..7f78c5f75549001135a83f0167ad977e038a2bd1 100644 (file)
--- a/lib/ext2fs/symlink.c
+++ b/lib/ext2fs/symlink.c
@@ -28,6 +28,22 @@
 #include "ext2_fs.h"
 #include "ext2fs.h"
 
+#ifndef HAVE_STRNLEN
+/*
+ * Incredibly, libc5 doesn't appear to have strnlen.  So we have to
+ * provide our own.
+ */
+static int my_strnlen(const char * s, int count)
+{
+       const char *cp = s;
+
+       while (count-- && *cp)
+               cp++;
+       return cp - s;
+}
+#define strnlen(str, x) my_strnlen((str),(x))
+#endif
+
 errcode_t ext2fs_symlink(ext2_filsys fs, ext2_ino_t parent, ext2_ino_t ino,
                         const char *name, const char *target)
 {