1 files changed, 124 insertions, 0 deletions
diff --git a/memelemmove.c b/memelemmove.c
new file mode 100644
index 0000000..2a90e26
--- /dev/null
+++ b/memelemmove.c
@@ -0,0 +1,124 @@
+/* See LICENSE file for copyright and license details. */
+#include "libsimple.h"
+#ifndef TEST
+
+
+#define MEMELEMMOVE(TYPE)\
+	do {\
+		TYPE *p;\
+		if (d <= s) {\
+			for (; n; n--, s++)\
+				if ((*d++ = *s) == elem)\
+					return d;\
+		} else {\
+			for (p = *(TYPE **)(void *)&s; n; n--, p++) {\
+				if (*p == elem) {\
+					n = (size_t)(p - s);\
+					p = &d[n + 1];\
+					do { d[n] = s[n]; } while (n--);\
+					return p;\
+				}\
+			}\
+			for (n = (size_t)(p - s); n;) {\
+				n--;\
+				d[n] = s[n];\
+			}\
+		}\
+		return NULL;\
+	} while (0)
+
+
+static uint16_t *
+memelemmove16(uint16_t *restrict d, const uint16_t *restrict s, uint16_t elem, size_t n)
+{
+	MEMELEMMOVE(uint16_t);
+}
+
+
+static uint32_t *
+memelemmove32(uint32_t *restrict d, const uint32_t *restrict s, uint32_t elem, size_t n)
+{
+	MEMELEMMOVE(uint32_t);
+}
+
+
+static uint64_t *
+memelemmove64(uint64_t *restrict d, const uint64_t *restrict s, uint64_t elem, size_t n)
+{
+	MEMELEMMOVE(uint64_t);
+}
+
+
+static char *
+memelemmovex(char *restrict d, const char *restrict s, const char *restrict elem, size_t size, size_t n)
+{
+	char *p;
+	size_t i;
+	if (d <= s) {
+		for (; n; s += size, n--) {
+			for (i = 0; i < size; i++)
+				d[i] = s[i];
+			for (i = 0; i < size; i++)
+				if (d[i] != elem[i])
+					goto next_forwards;
+			d += size;
+			return d;
+		next_forwards:
+			d += size;
+		}
+		return NULL;
+	} else {
+		for (p = *(char **)(void *)&s; n; n--) {
+			for (i = 0; i < size; i++)
+				if (p[i] != elem[i])
+					goto next_backwards;
+			
+			p += size;
+			n = (size_t)(p - s);
+			p = &d[n];
+			goto out_backwards;
+		next_backwards:
+			p += size;
+		}
+		n = (size_t)(p - s);
+		p = NULL;
+	out_backwards:
+		while (n) {
+			n--;
+			d[n] = s[n];
+		}
+		return p;
+	}
+}
+
+
+void *
+libsimple_memelemmove(void *d, const void *s, const void *restrict elem, size_t size, size_t n) /* TODO test, man */
+{
+	switch (size) {
+	case 0:
+		return d;
+	case 1:
+		return memcmove(d, s, *(const char *)elem, n);
+	case 2:
+		return memelemmove16(d, s, *(const uint16_t *)elem, n);
+	case 4:
+		return memelemmove32(d, s, *(const uint32_t *)elem, n);
+	case 8:
+		return memelemmove64(d, s, *(const uint64_t *)elem, n);
+	default:
+		return memelemmovex(d, s, elem, size, n);
+	}
+}
+
+
+#else
+#include "test.h"
+
+int
+main(void)
+{
+	return 0;
+}
+
+#endif