1 files changed, 75 insertions, 0 deletions
diff --git a/strrcasestr.c b/strrcasestr.c
new file mode 100644
index 0000000..9bd40b3
--- /dev/null
+++ b/strrcasestr.c
@@ -0,0 +1,75 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+
+
+char *
+libsimple_strrcasestr(const char *h_, const char *n)
+{
+	char *h = *(char **)(void *)&h_;
+	size_t hn = strlen(h);
+	size_t nn = strlen(n);
+	if (hn < nn)
+		return NULL;
+	for (h += hn -= nn; hn--; h--)
+		if (!strcasecmp(h, n))
+			return h;
+	return NULL;
+}
+
+
+#ifdef TEST
+#include <assert.h>
+
+int
+main(void)
+{
+	assert(!strcmp(libsimple_strrcasestr("", ""), ""));
+	assert(!strcmp(libsimple_strrcasestr("test", ""), ""));
+	assert(!libsimple_strrcasestr("", ""));
+	assert(!libsimple_strrcasestr("t", "t"));
+	assert(!strcmp(libsimple_strrcasestr("test", "t"), "t"));
+	assert(!strcmp(libsimple_strrcasestr("test", "e"), "est"));
+	assert(!strcmp(libsimple_strrcasestr("test", "s"), "st"));
+	assert(!libsimple_strrcasestr("test", "x"));
+	assert(!strcmp(libsimple_strrcasestr("test", "te"), "test"));
+	assert(!strcmp(libsimple_strrcasestr("test", "es"), "est"));
+	assert(!strcmp(libsimple_strrcasestr("test", "st"), "st"));
+	assert(!libsimple_strrcasestr("test", "xx"));
+	assert(!strcmp(libsimple_strrcasestr("abc", "c"), "c"));
+	assert(!strcmp(libsimple_strrcasestr("abc", "bc"), "bc"));
+	assert(!strcmp(libsimple_strrcasestr("abc", "abc"), "abc"));
+	assert(!strcmp(libsimple_strrcasestr("abcabc", "bc"), "bc"));
+
+	assert(!strcmp(libsimple_strrcasestr("TEST", ""), ""));
+	assert(!libsimple_strrcasestr("T", "test"));
+	assert(!strcmp(libsimple_strrcasestr("TEST", "t"), "T"));
+	assert(!strcmp(libsimple_strrcasestr("TEST", "e"), "EST"));
+	assert(!strcmp(libsimple_strrcasestr("TEST", "s"), "ST"));
+	assert(!libsimple_strrcasestr("TEST", "x"));
+	assert(!strcmp(libsimple_strrcasestr("TEST", "te"), "TEST"));
+	assert(!strcmp(libsimple_strrcasestr("TEST", "es"), "EST"));
+	assert(!strcmp(libsimple_strrcasestr("TEST", "st"), "ST"));
+	assert(!libsimple_strrcasestr("TEST", "xx"));
+	assert(!strcmp(libsimple_strrcasestr("ABC", "c"), "C"));
+	assert(!strcmp(libsimple_strrcasestr("ABC", "bc"), "BC"));
+	assert(!strcmp(libsimple_strrcasestr("ABC", "abc"), "ABC"));
+	assert(!strcmp(libsimple_strrcasestr("ABCABC", "bc"), "BC"));
+
+	assert(!libsimple_strrcasestr("", "TEST"));
+	assert(!libsimple_strrcasestr("t", "TEST"));
+	assert(!strcmp(libsimple_strrcasestr("test", "T"), "t"));
+	assert(!strcmp(libsimple_strrcasestr("test", "E"), "est"));
+	assert(!strcmp(libsimple_strrcasestr("test", "S"), "st"));
+	assert(!libsimple_strrcasestr("test", "X"));
+	assert(!strcmp(libsimple_strrcasestr("test", "TE"), "test"));
+	assert(!strcmp(libsimple_strrcasestr("test", "ES"), "est"));
+	assert(!strcmp(libsimple_strrcasestr("test", "ST"), "st"));
+	assert(!libsimple_strrcasestr("test", "XX"));
+	assert(!strcmp(libsimple_strrcasestr("abc", "C"), "c"));
+	assert(!strcmp(libsimple_strrcasestr("abc", "BC"), "bc"));
+	assert(!strcmp(libsimple_strrcasestr("abc", "ABC"), "abc"));
+	assert(!strcmp(libsimple_strrcasestr("abcabc", "BC"), "bc"));
+	return 0;
+}
+
+#endif