1 files changed, 41 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/mman/mmap.c b/libc-top-half/musl/src/mman/mmap.c
new file mode 100644
index 0000000..eff88d8
--- /dev/null
+++ b/libc-top-half/musl/src/mman/mmap.c
@@ -0,0 +1,41 @@
+#include <unistd.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <stdint.h>
+#include <limits.h>
+#include "syscall.h"
+
+static void dummy(void) { }
+weak_alias(dummy, __vm_wait);
+
+#define UNIT SYSCALL_MMAP2_UNIT
+#define OFF_MASK ((-0x2000ULL << (8*sizeof(syscall_arg_t)-1)) | (UNIT-1))
+
+void *__mmap(void *start, size_t len, int prot, int flags, int fd, off_t off)
+{
+	long ret;
+	if (off & OFF_MASK) {
+		errno = EINVAL;
+		return MAP_FAILED;
+	}
+	if (len >= PTRDIFF_MAX) {
+		errno = ENOMEM;
+		return MAP_FAILED;
+	}
+	if (flags & MAP_FIXED) {
+		__vm_wait();
+	}
+#ifdef SYS_mmap2
+	ret = __syscall(SYS_mmap2, start, len, prot, flags, fd, off/UNIT);
+#else
+	ret = __syscall(SYS_mmap, start, len, prot, flags, fd, off);
+#endif
+	/* Fixup incorrect EPERM from kernel. */
+	if (ret == -EPERM && !start && (flags&MAP_ANON) && !(flags&MAP_FIXED))
+		ret = -ENOMEM;
+	return (void *)__syscall_ret(ret);
+}
+
+weak_alias(__mmap, mmap);
+
+weak_alias(mmap, mmap64);