summaryrefslogtreecommitdiff
path: root/compat/memmem.c
diff options
context:
space:
mode:
Diffstat (limited to 'compat/memmem.c')
-rw-r--r--compat/memmem.c29
1 files changed, 29 insertions, 0 deletions
diff --git a/compat/memmem.c b/compat/memmem.c
new file mode 100644
index 0000000..cd0d877
--- /dev/null
+++ b/compat/memmem.c
@@ -0,0 +1,29 @@
+#include "../git-compat-util.h"
+
+void *gitmemmem(const void *haystack, size_t haystack_len,
+ const void *needle, size_t needle_len)
+{
+ const char *begin = haystack;
+ const char *last_possible = begin + haystack_len - needle_len;
+
+ /*
+ * The first occurrence of the empty string is deemed to occur at
+ * the beginning of the string.
+ */
+ if (needle_len == 0)
+ return (void *)begin;
+
+ /*
+ * Sanity check, otherwise the loop might search through the whole
+ * memory.
+ */
+ if (haystack_len < needle_len)
+ return NULL;
+
+ for (; begin <= last_possible; begin++) {
+ if (!memcmp(begin, needle, needle_len))
+ return (void *)begin;
+ }
+
+ return NULL;
+}