Create local C library implementation (1/2)

- This change is split into two separate patches in order to
  simplify the history as interpreted by 'git'. The split is
  between the move/rename and addition of new files.
- Remove dependency on toolchain C library headers and functions in
  order to ensure behavioural compatibility between toolchains.
- Use FreeBSD as reference for C library implementation.
- Do not let GCC use default library include paths.
- Remove unused definitions in modified headers and implementations.
- Move C library files to 'lib/stdlib' and 'include/stdlib'.
- Break std.c functions out into separate files.

Change-Id: I91cddfb3229775f770ad781589670c57d347a154

1 files changed, 103 insertions, 0 deletions

diff --git a/lib/stdlib/mem.c b/lib/stdlib/mem.c
new file mode 100644
index 000000000..e072710be
--- /dev/null
+++ b/lib/stdlib/mem.c
@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) 2013, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <stddef.h> /* size_t */
+
+/*
+ * Fill @count bytes of memory pointed to by @dst with @val
+ */
+void *memset(void *dst, int val, size_t count)
+{
+	char *ptr = dst;
+
+	while (count--)
+		*ptr++ = val;
+
+	return dst;
+}
+
+/*
+ * Compare @len bytes of @s1 and @s2
+ */
+int memcmp(const void *s1, const void *s2, size_t len)
+{
+	const char *s = s1;
+	const char *d = s2;
+	char dc;
+	char sc;
+
+	while (len--) {
+		sc = *s++;
+		dc = *d++;
+		if (sc - dc)
+			return (sc - dc);
+	}
+
+	return 0;
+}
+
+
+/*
+ * Move @len bytes from @src to @dst
+ */
+void *memmove(void *dst, const void *src, size_t len)
+{
+	const char *s = src;
+	char *d = dst;
+
+	while (len--)
+		*d++ = *s++;
+	return d;
+}
+
+/*
+ * Copy @len bytes from @src to @dst
+ */
+void *memcpy(void *dst, const void *src, size_t len)
+{
+	return memmove(dst, src, len);
+}
+
+
+/*
+ * Scan @len bytes of @src for value @c
+ */
+void *memchr(const void *src, int c, size_t len)
+{
+	const char *s = src;
+
+	while (len--) {
+		if (*s == c)
+			return (void *) s;
+		s++;
+	}
+
+	return NULL;
+}