user: implement mlibc as the libc, finally.

It's finally done..

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

user/include/mlibc/options/posix/generic/sys-shm.cpp

@@ -0,0 +1,45 @@
+#include <sys/shm.h>
+#include <errno.h>
+
+#include <bits/ensure.h>
+#include <mlibc/debug.hpp>
+#include <mlibc/posix-sysdeps.hpp>
+
+void *shmat(int shmid, const void *shmaddr, int shmflg) {
+	void *ret;
+	auto sysdep = MLIBC_CHECK_OR_ENOSYS(mlibc::sys_shmat, ((void *)-1));
+	if(int e = sysdep(&ret, shmid, shmaddr, shmflg); e) {
+		errno = e;
+		return ((void *)-1);
+	}
+	return ret;
+}
+
+int shmctl(int shmid, int cmd, struct shmid_ds *buf) {
+	int ret;
+	auto sysdep = MLIBC_CHECK_OR_ENOSYS(mlibc::sys_shmctl, -1);
+	if(int e = sysdep(&ret, shmid, cmd, buf); e) {
+		errno = e;
+		return -1;
+	}
+	return ret;
+}
+
+int shmdt(const void *shmaddr) {
+	auto sysdep = MLIBC_CHECK_OR_ENOSYS(mlibc::sys_shmdt, -1);
+	if(int e = sysdep(shmaddr); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+int shmget(key_t key, size_t size, int shmflg) {
+	int ret;
+	auto sysdep = MLIBC_CHECK_OR_ENOSYS(mlibc::sys_shmget, -1);
+	if(int e = sysdep(&ret, key, size, shmflg); e) {
+		errno = e;
+		return -1;
+	}
+	return ret;
+}