user: implement mlibc as the libc, finally.

It's finally done..

Signed-off-by: kaguya <vpshinomiya@protonmail.com>

user/include/mlibc/tests/ansi/mbrtoc32.c

@@ -0,0 +1,55 @@
+#include <assert.h>
+#include <locale.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <uchar.h>
+
+struct {
+	size_t ret;
+	char32_t c32;
+	uint8_t bytes[4];
+} expected_results[] = {
+	{1, 0x7A, {0x7A, 0, 0, 0}},
+	{2, 0xDF, {0xC3, 0x9F, 0, 0}},
+	{3, 0x6C34, {0xE6, 0xB0, 0xB4, 0}},
+	{4, 0x1F34C, {0xF0, 0x9F, 0x8D, 0x8C}},
+};
+
+int main() {
+	setlocale(LC_ALL, "en_US.utf8");
+
+	size_t ret = 0;
+
+	char *str = "z\u00df\u6c34\U0001F34C";
+
+	fprintf(stderr, "string: '%s'\n", str);
+
+	mbstate_t state = {};
+	char32_t c32;
+	size_t loop = 0;
+	while((ret = mbrtoc32(&c32, str, strlen(str), &state))) {
+		assert(ret != (size_t)-3);
+		if(ret == (size_t)-1)
+			break;
+		if(ret == (size_t)-2)
+			break;
+
+		fprintf(stderr, "Next UTF-32 char: 0x%x obtained from %zu bytes [", c32, ret);
+		for(size_t n = 0; n < ret; ++n) {
+			fprintf(stderr, " 0x%02x ", (uint8_t) str[n]);
+		}
+		fprintf(stderr, "]\n");
+
+		assert(ret == expected_results[loop].ret);
+		assert(c32 == expected_results[loop].c32);
+		for(size_t n = 0; n < ret; ++n) {
+			assert((uint8_t) str[n] == expected_results[loop].bytes[n]);
+		}
+
+		str += ret;
+		loop++;
+	}
+
+	return 0;
+}