[U-Boot-Users] [PATCH 1/2] Add memmem() library function

[Grant Likely]

From: Grant Likely <grant.likely at secretlab.ca>

Signed-off-by: Grant Likely <grant.likely at secretlab.ca>
---

 include/linux/string.h |    3 +++
 lib_generic/string.c   |   34 ++++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 0 deletions(-)

diff --git a/include/linux/string.h b/include/linux/string.h
index 6239039..e18bcbf 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -81,6 +81,9 @@ extern int memcmp(const void *,const void *,__kernel_size_t);
 #ifndef __HAVE_ARCH_MEMCHR
 extern void * memchr(const void *,int,__kernel_size_t);
 #endif
+#ifndef __HAVE_ARCH_MEMMEM
+extern void * memmem(const void *,__kernel_size_t,const void *,__kernel_size_t);
+#endif
 
 #ifdef __cplusplus
 }
diff --git a/lib_generic/string.c b/lib_generic/string.c
index e0b793a..36262de 100644
--- a/lib_generic/string.c
+++ b/lib_generic/string.c
@@ -574,5 +574,39 @@ void *memchr(const void *s, int c, size_t n)
 	}
 	return NULL;
 }
+#endif
+
+#ifndef __HAVE_ARCH_MEMMEM
+/**
+ * memmem - Find a sequence in an area of memory
+ * @a: The memory area
+ * @len1: Size of the memory area
+ * @b: The sequence to search for
+ * @len2: Size of the sequence
+ *
+ * returns the address of the first occurrence of @b, or %NULL
+ * if @b is not found
+ */
+void *memmem (const void *m, size_t ml, const void *s, size_t sl)
+{
+	const char * start = m;
+	const char * end = m + ml;
 
+	if (sl > ml)
+		return NULL;
+
+	while (start < end)
+	{
+		size_t len = sl;
+		const char * ptr1 = start;
+		const char * ptr2 = s;
+		while (len > 0 && *ptr1++ == *ptr2++)
+			len--;
+		if (len == 0)
+			return (void *)start;
+		start++;
+	}
+
+	return NULL;
+}
 #endif