user: implement mlibc as the libc, finally.

It's finally done..

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

user/include/mlibc/options/posix/generic/posix_string.cpp

@@ -0,0 +1,179 @@
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <bits/ensure.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+#include <signal.h>
+
+#include <mlibc/debug.hpp>
+
+char *strdup(const char *string) {
+	auto num_bytes = strlen(string);
+
+	char *new_string = (char *)malloc(num_bytes + 1);
+	if(!new_string) // TODO: set errno
+		return nullptr;
+
+	memcpy(new_string, string, num_bytes);
+	new_string[num_bytes] = 0;
+	return new_string;
+}
+
+char *strndup(const char *string, size_t max_size) {
+	auto num_bytes = strnlen(string, max_size);
+	char *new_string = (char *)malloc(num_bytes + 1);
+	if(!new_string) // TODO: set errno
+		return nullptr;
+
+	memcpy(new_string, string, num_bytes);
+	new_string[num_bytes] = 0;
+	return new_string;
+}
+
+char *stpcpy(char *__restrict dest, const char *__restrict src) {
+	auto n = strlen(src);
+	memcpy(dest, src, n + 1);
+	return dest + n;
+}
+
+char *stpncpy(char *__restrict dest, const char *__restrict src, size_t n) {
+	size_t nulls, copied, srcLen = strlen(src);
+	if (n >= srcLen) {
+		nulls = n - srcLen;
+		copied = srcLen;
+	} else {
+		nulls = 0;
+		copied = n;
+	}
+
+	memcpy(dest, src, copied);
+	memset(dest + srcLen, 0, nulls);
+	return dest + n - nulls;
+}
+
+size_t strnlen(const char *s, size_t n) {
+	size_t len = 0;
+	while(len < n && s[len])
+		++len;
+	return len;
+}
+
+char *strsep(char **m, const char *del) {
+	__ensure(m);
+
+	auto tok = *m;
+	if(!tok)
+		return nullptr;
+
+	// Replace the following delimiter by a null-terminator.
+	// After this loop: *p is null iff we reached the end of the string.
+	auto p = tok;
+	while(*p && !strchr(del, *p))
+		p++;
+
+	if(*p) {
+		*p = 0;
+		*m = p + 1;
+	}else{
+		*m = nullptr;
+	}
+	return tok;
+}
+
+char *strsignal(int sig) {
+	#define CASE_FOR(sigconst) case sigconst: s = #sigconst; break;
+	const char *s;
+	switch(sig) {
+	CASE_FOR(SIGABRT)
+	CASE_FOR(SIGFPE)
+	CASE_FOR(SIGILL)
+	CASE_FOR(SIGINT)
+	CASE_FOR(SIGSEGV)
+	CASE_FOR(SIGTERM)
+	CASE_FOR(SIGPROF)
+	CASE_FOR(SIGIO)
+	CASE_FOR(SIGPWR)
+	CASE_FOR(SIGALRM)
+	CASE_FOR(SIGBUS)
+	CASE_FOR(SIGCHLD)
+	CASE_FOR(SIGCONT)
+	CASE_FOR(SIGHUP)
+	CASE_FOR(SIGKILL)
+	CASE_FOR(SIGPIPE)
+	CASE_FOR(SIGQUIT)
+	CASE_FOR(SIGSTOP)
+	CASE_FOR(SIGTSTP)
+	CASE_FOR(SIGTTIN)
+	CASE_FOR(SIGTTOU)
+	CASE_FOR(SIGUSR1)
+	CASE_FOR(SIGUSR2)
+	CASE_FOR(SIGSYS)
+	CASE_FOR(SIGTRAP)
+	CASE_FOR(SIGURG)
+	CASE_FOR(SIGVTALRM)
+	CASE_FOR(SIGXCPU)
+	CASE_FOR(SIGXFSZ)
+	CASE_FOR(SIGWINCH)
+	default:
+		mlibc::infoLogger() << "mlibc: Unknown signal number " << sig << frg::endlog;
+		s = "Unknown signal number";
+	}
+	return const_cast<char *>(s);
+}
+
+char *strcasestr(const char *s, const char *pattern) {
+	size_t plen = strlen(pattern);
+	const char *p = s;
+	while(*p) {
+		// Need strncasecmp() to avoid checking past the end of a successful match.
+		if(!strncasecmp(p, pattern, plen))
+			return const_cast<char *>(p);
+		++p;
+	}
+	return nullptr;
+}
+
+void *memccpy(void *__restrict, const void *__restrict, int, size_t) {
+	__ensure(!"Not implemented");
+	__builtin_unreachable();
+}
+
+// This implementation was taken from musl
+void *memrchr(const void *m, int c, size_t n) {
+	const unsigned char *s = (const unsigned char *)m;
+	c = (unsigned char)c;
+	while(n--) {
+		if(s[n] == c)
+			return (void *)(s + n);
+	}
+	return nullptr;
+}
+
+char *strerror_l(int errnum, locale_t) {
+	mlibc::infoLogger() << "mlibc: strerror_l locale is ignored!" << frg::endlog;
+	return strerror(errnum);
+}
+
+// BSD extensions.
+// Taken from musl
+size_t strlcpy(char *d, const char *s, size_t n) {
+	char *d0 = d;
+
+	if(!n--)
+		goto finish;
+	for(; n && (*d=*s); n--, s++, d++);
+	*d = 0;
+finish:
+	return d-d0 + strlen(s);
+}
+
+size_t strlcat(char *d, const char *s, size_t n) {
+	size_t l = strnlen(d, n);
+	if(l == n) {
+		return l + strlen(s);
+	}
+	return l + strlcpy(d + l, s, n - l);
+}