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-mman.cpp

@@ -0,0 +1,181 @@
+
+#include <errno.h>
+#include <limits.h>
+#include <pthread.h>
+#include <unistd.h>
+#include <sys/mman.h>
+#include <bits/ensure.h>
+
+#include <mlibc/debug.hpp>
+#include <mlibc/posix-sysdeps.hpp>
+
+int mprotect(void *pointer, size_t size, int prot) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_vm_protect, -1);
+	if(int e = mlibc::sys_vm_protect(pointer, size, prot); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+int mlock(const void *addr, size_t len) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_mlock, -1);
+	if(int e = mlibc::sys_mlock(addr, len); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+int mlockall(int flags) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_mlockall, -1);
+	if(int e = mlibc::sys_mlockall(flags); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+int munlock(const void *addr, size_t len) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_munlock, -1);
+	if(int e = mlibc::sys_munlock(addr, len); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+int munlockall(void) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_munlockall, -1);
+	if(int e = mlibc::sys_munlockall(); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+
+int posix_madvise(void *addr, size_t length, int advice) {
+	if(!mlibc::sys_posix_madvise) {
+		MLIBC_MISSING_SYSDEP();
+		return ENOSYS;
+	}
+	return mlibc::sys_posix_madvise(addr, length, advice);
+}
+
+int msync(void *addr, size_t length, int flags) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_msync, -1);
+	if(int e = mlibc::sys_msync(addr, length, flags); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+void *mmap(void *hint, size_t size, int prot, int flags, int fd, off_t offset) {
+	void *window;
+	if(int e = mlibc::sys_vm_map(hint, size, prot, flags, fd, offset, &window); e) {
+		errno = e;
+		return (void *)-1;
+	}
+	return window;
+}
+
+[[gnu::alias("mmap")]] void *mmap64(void *hint, size_t size, int prot, int flags, int fd, off64_t offset);
+
+int munmap(void *pointer, size_t size) {
+	if(int e = mlibc::sys_vm_unmap(pointer, size); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+
+// The implementation of shm_open and shm_unlink is taken from musl.
+namespace {
+	char *shm_mapname(const char *name, char *buf) {
+		char *p;
+		while(*name == '/')
+			name++;
+		if(*(p = strchrnul(name, '/')) || p == name ||
+			(p - name <= 2 && name[0] == '.' && p[-1] == '.')) {
+			errno = EINVAL;
+			return nullptr;
+		}
+		if(p - name > NAME_MAX) {
+			errno = ENAMETOOLONG;
+			return nullptr;
+		}
+		memcpy(buf, "/dev/shm/", 9);
+		memcpy(buf + 9, name, p - name + 1);
+		return buf;
+	}
+} // namespace
+
+int shm_open(const char *name, int flags, mode_t mode) {
+	int cs;
+	char buf[NAME_MAX + 10];
+	if(!(name = shm_mapname(name, buf)))
+		return -1;
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+	int fd = open(name, flags | O_NOFOLLOW | O_CLOEXEC | O_NONBLOCK, mode);
+	pthread_setcancelstate(cs, nullptr);
+	return fd;
+}
+
+int shm_unlink(const char *name) {
+	char buf[NAME_MAX + 10];
+	if(!(name = shm_mapname(name, buf)))
+		return -1;
+	return unlink(name);
+}
+
+#if __MLIBC_LINUX_OPTION
+void *mremap(void *pointer, size_t size, size_t new_size, int flags, ...) {
+	__ensure(flags == MREMAP_MAYMOVE);
+
+	void *window;
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_vm_remap, (void *)-1);
+	if(int e = mlibc::sys_vm_remap(pointer, size, new_size, &window); e) {
+		errno = e;
+		return (void *)-1;
+	}
+	return window;
+}
+
+int remap_file_pages(void *, size_t, int, size_t, int) {
+	__ensure(!"Not implemented");
+	__builtin_unreachable();
+}
+
+int memfd_create(const char *name, unsigned int flags) {
+	int ret = -1;
+
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_memfd_create, -1);
+	if(int e = mlibc::sys_memfd_create(name, flags, &ret)) {
+		errno = e;
+		return -1;
+	}
+
+	return ret;
+}
+
+int madvise(void *addr, size_t length, int advice) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_madvise, -1);
+	if(int e = mlibc::sys_madvise(addr, length, advice)) {
+		errno = e;
+		return -1;
+	}
+
+	return 0;
+}
+
+int mincore(void *addr, size_t length, unsigned char *vec) {
+	MLIBC_CHECK_OR_ENOSYS(mlibc::sys_munlockall, -1);
+	if(int e = mlibc::sys_mincore(addr, length, vec); e) {
+		errno = e;
+		return -1;
+	}
+	return 0;
+}
+#endif /* __MLIBC_LINUX_OPTION */