[vlc-commits] compat: add memrchr replacement

[Jean-Baptiste Kempf]

vlc | branch: master | Jean-Baptiste Kempf <jb at videolan.org> | Sun Jul 17 21:09:17 2016 +0200| [a051de1ac61c0fea6f72aa3a880248dd85da210b] | committer: Jean-Baptiste Kempf

compat: add memrchr replacement

This is a very simple replacement. It probably can be better. Feel free.

> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=a051de1ac61c0fea6f72aa3a880248dd85da210b
---

 compat/memrchr.c     |   41 +++++++++++++++++++++++++++++++++++++++++
 configure.ac         |    2 +-
 include/vlc_fixups.h |    4 ++++
 3 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/compat/memrchr.c b/compat/memrchr.c
new file mode 100644
index 0000000..c7a038c
--- /dev/null
+++ b/compat/memrchr.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2007 Todd C. Miller <Todd.Miller at courtesan.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <string.h>
+
+/*
+ * Reverse memchr()
+ * Find the last occurrence of 'c' in the buffer 's' of size 'n'.
+ */
+void *
+memrchr(const void *s, int c, size_t n)
+{
+    const unsigned char *cp;
+
+    if (n != 0) {
+        cp = (unsigned char *)s + n;
+        do {
+            if (*(--cp) == (unsigned char)c)
+                return((void *)cp);
+        } while (--n != 0);
+    }
+    return(NULL);
+}
diff --git a/configure.ac b/configure.ac
index 3c31066..8a855f2 100644
--- a/configure.ac
+++ b/configure.ac
@@ -584,7 +584,7 @@ need_libc=false
 dnl Check for usual libc functions
 AC_CHECK_DECLS([nanosleep],,,[#include <time.h>])
 AC_CHECK_FUNCS([daemon fcntl flock fstatvfs fork getenv getpwuid_r isatty lstat memalign mkostemp mmap open_memstream openat pread posix_fadvise posix_madvise setlocale stricmp strnicmp strptime uselocale pthread_cond_timedwait_monotonic_np pthread_condattr_setclock])
-AC_REPLACE_FUNCS([atof atoll dirfd fdopendir ffsll flockfile fsync getdelim getpid lldiv nrand48 poll posix_memalign recvmsg rewind sendmsg setenv strcasecmp strcasestr strdup strlcpy strndup strnlen strnstr strsep strtof strtok_r strtoll swab tdestroy timegm timespec_get strverscmp])
+AC_REPLACE_FUNCS([atof atoll dirfd fdopendir ffsll flockfile fsync getdelim getpid lldiv memrchr nrand48 poll posix_memalign recvmsg rewind sendmsg setenv strcasecmp strcasestr strdup strlcpy strndup strnlen strnstr strsep strtof strtok_r strtoll swab tdestroy timegm timespec_get strverscmp])
 AC_REPLACE_FUNCS([gettimeofday])
 AC_CHECK_FUNCS(fdatasync,,
   [AC_DEFINE(fdatasync, fsync, [Alias fdatasync() to fsync() if missing.])
diff --git a/include/vlc_fixups.h b/include/vlc_fixups.h
index 52209dc..d62920a 100644
--- a/include/vlc_fixups.h
+++ b/include/vlc_fixups.h
@@ -268,6 +268,10 @@ int unsetenv (const char *);
 int posix_memalign (void **, size_t, size_t);
 #endif
 
+#ifndef HAVE_MEMRCHR
+void *memrchr(const void *, int, size_t);
+#endif
+
 /* locale.h */
 #ifndef HAVE_USELOCALE
 #define LC_ALL_MASK      0