0.3.0: converge relibc to upstream 0.6.0 + Red Bear patches

tests/string/memmem.c

@@ -0,0 +1,31 @@
+#include <assert.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "test_helpers.h"
+
+int main(void) {
+    uint8_t haystack[] = {1, 1, 2, 1, 2, 3, 1, 2, 3, 4};
+    uint8_t present_needle[] = {1, 2, 3};
+    uint8_t absent_needle[] = {1, 2, 3, 4, 5};
+    uint8_t long_needle[] = {1, 1, 2, 1, 2, 3, 1, 2, 3, 4, 1};
+
+    size_t haystacklen = sizeof(haystack);
+    size_t present_needlelen = sizeof(present_needle);
+    size_t absent_needlelen = sizeof(absent_needle);
+    size_t long_needlelen = sizeof(long_needle);
+
+    uint8_t *present_needle_match_ptr = memmem(haystack, haystacklen, present_needle, present_needlelen);
+    assert(present_needle_match_ptr == haystack + 3);
+
+    uint8_t *absent_needle_match_ptr = memmem(haystack, haystacklen, absent_needle, absent_needlelen);
+    assert(absent_needle_match_ptr == NULL);
+
+    // Explicitly specified to return haystack for needlelen == 0.
+    uint8_t *zero_needle_match_ptr = memmem(haystack, haystacklen, present_needle, 0);
+    assert(zero_needle_match_ptr == haystack);
+
+    uint8_t *long_needle_match_ptr = memmem(haystack, haystacklen, long_needle, long_needlelen);
+    assert(long_needle_match_ptr == NULL);
+}