From cb7c5f9921c1228d4823dae492a37c18254c38ce Mon Sep 17 00:00:00 2001
From: Gregory Nutt <gnutt@nuttx.org>
Date: Wed, 22 Feb 2017 10:20:58 -0600
Subject: [PATCH] Implement strings.h macros as inline functions when possible
 for better C++ compatibility.

---
 include/cxx/cstring               | 18 +++-----
 include/strings.h                 | 68 ++++++++++++++++++++++++++-----
 sched/pthread/pthread_mutexlock.c |  2 +-
 3 files changed, 63 insertions(+), 25 deletions(-)

diff --git a/include/cxx/cstring b/include/cxx/cstring
index e2b7367ab7..038080e75d 100644
--- a/include/cxx/cstring
+++ b/include/cxx/cstring
@@ -44,19 +44,6 @@
 #include <string.h>
 #include <strings.h>
 
-//***************************************************************************
-// Pre-processor Definitions
-//***************************************************************************
-
-// Remove macros defined in strings.h.  The index() definition, in
-// particular, can cause naming collision problems.
-
-#undef bcmp
-#undef bcopy
-#undef bzero
-#undef index
-#undef rindex
-
 //***************************************************************************
 // Namespace
 //***************************************************************************
@@ -100,6 +87,11 @@ namespace std
 
   // Declared in legacy strings.h
 
+  using ::bcmp;
+  using ::bcopy;
+  using ::bzero;
+  using ::index;
+  using ::rindex;
   using ::ffs;
   using ::strcasecmp;
   using ::strncasecmp;
diff --git a/include/strings.h b/include/strings.h
index e9812335f7..6fdaec2275 100644
--- a/include/strings.h
+++ b/include/strings.h
@@ -47,24 +47,28 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
+
+#if !defined(CONFIG_HAVE_INLINE) && !defined(__cplusplus)
 /* Compatibility definitions
  *
  * Marked LEGACY in Open Group Base Specifications Issue 6/IEEE Std 1003.1-2004
  * Removed from Open Group Base Specifications Issue 7/IEEE Std 1003.1-2008
  */
 
-#define bcmp(b1,b2,len)  memcmp(b1,b2,(size_t)len)
-#define bcopy(b1,b2,len) (void)memmove(b2,b1,len)
+#  define bcmp(b1,b2,len)  memcmp(b1,b2,(size_t)len)
+#  define bcopy(b1,b2,len) (void)memmove(b2,b1,len)
 
-#ifndef CONFIG_LIBC_ARCH_BZERO
-# define bzero(s,n)      (void)memset(s,0,n)
-#endif
+#  ifndef CONFIG_LIBC_ARCH_BZERO
+#    define bzero(s,n)      (void)memset(s,0,n)
+#  endif
 
-#define index(s,c)       strchr(s,c)
-#define rindex(s,c)      strrchr(s,c)
+#  define index(s,c)       strchr(s,c)
+#  define rindex(s,c)      strrchr(s,c)
+
+#endif /* !CONFIG_HAVE_INLINE && !__cplusplus */
 
 /****************************************************************************
- * Public Function Prototypes
+ * Inline Functions
  ****************************************************************************/
 
 #undef EXTERN
@@ -76,9 +80,51 @@ extern "C"
 #define EXTERN extern
 #endif
 
-int ffs(int j);
-int strcasecmp(FAR const char *, FAR const char *);
-int strncasecmp(FAR const char *, FAR const char *, size_t);
+#if defined(CONFIG_HAVE_INLINE) || defined(__cplusplus)
+/* Compatibility inline functions.
+ *
+ * Marked LEGACY in Open Group Base Specifications Issue 6/IEEE Std 1003.1-2004
+ * Removed from Open Group Base Specifications Issue 7/IEEE Std 1003.1-2008
+ */
+
+static inline int bcmp(FAR const void *b1, FAR const void *b2, size_t len)
+{
+  return memcmp(b1, b2, len);
+}
+
+static inline void bcopy(FAR const void *b1, FAR void *b2, size_t len)
+{
+  (void)memmove(b1, b2, len);
+}
+
+#ifndef CONFIG_LIBC_ARCH_BZERO
+static inline void bzero(FAR void *s, size_t len)
+{
+  (void)memset(s, 0, len);
+}
+#endif
+
+static inline FAR char *index(FAR const char *s, int c)
+{
+  return strchr(s, c);
+}
+
+static inline FAR char *rindex(FAR const char *s, int c)
+{
+  return strrchr(s, c);
+}
+#endif /* CONFIG_HAVE_INLINE || __cplusplus */
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#ifdef CONFIG_LIBC_ARCH_BZERO
+void bzero(FAR void *s, size_t len);
+#endif
+int  ffs(int j);
+int  strcasecmp(FAR const char *, FAR const char *);
+int  strncasecmp(FAR const char *, FAR const char *, size_t);
 
 #undef EXTERN
 #if defined(__cplusplus)
diff --git a/sched/pthread/pthread_mutexlock.c b/sched/pthread/pthread_mutexlock.c
index ebd650df6f..f94890505d 100644
--- a/sched/pthread/pthread_mutexlock.c
+++ b/sched/pthread/pthread_mutexlock.c
@@ -150,7 +150,7 @@ int pthread_mutex_lock(FAR pthread_mutex_t *mutex)
 
           ret = pthread_takesemaphore((FAR sem_t *)&mutex->sem);
 
-          /* If we succussfully obtained the semaphore, then indicate
+          /* If we successfully obtained the semaphore, then indicate
            * that we own it.
            */