string: fix prototype of memdup()

It doesn't make sense to restrict memdup() to only return char*
pointers, especially when it is already defined to accept void*. This
makes it uglier to use to e.g. duplicate a struct.

Make it return void*, just as kmemdup() does in the kernel (and which
our kmemdup() in fact also does).

While in here, make a small optimization: memcpy() is defined to
return the destination register, so we write this in a way that the
compiler may do a tail call.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Rasmus Villemoes <ravi@prevas.dk>

diff --git a/include/linux/string.h b/include/linux/string.h
index d943fcce690c572c197d5e17309a406be8e30ae8..9e47fe01c165e5a52e6704eaec251ab6d0da2a2c 100644 (file)
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -142,7 +142,7 @@ void *memchr_inv(const void *, int, size_t);
  *     memory is available
  *
  */
-char *memdup(const void *src, size_t len);
+void *memdup(const void *src, size_t len);
 
 unsigned long ustrtoul(const char *cp, char **endp, unsigned int base);
 unsigned long long ustrtoull(const char *cp, char **endp, unsigned int base);

diff --git a/lib/string.c b/lib/string.c
index d56f88d4a847a43f7808ca85366faf9db2830bd7..c2813e0f8549ae05e489b2ef70fec50b90ac3b66 100644 (file)
--- a/lib/string.c
+++ b/lib/string.c
@@ -667,17 +667,15 @@ void * memscan(void * addr, int c, size_t size)
 }
 #endif
 
-char *memdup(const void *src, size_t len)
+void *memdup(const void *src, size_t len)
 {
-       char *p;
+       void *p;
 
        p = malloc(len);
        if (!p)
                return NULL;
 
-       memcpy(p, src, len);
-
-       return p;
+       return memcpy(p, src, len);
 }
 
 #ifndef __HAVE_ARCH_STRNSTR