From f39f262c76f5ab4624e14e69bf1ffacafc5cc803 Mon Sep 17 00:00:00 2001
From: Antti Kantee <pooka@iki.fi>
Date: Wed, 4 Sep 2013 22:51:36 +0300
Subject: [PATCH] Add some sort of emulation for mmap

---
 Makefile     |  1 +
 emul.c       | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 libc_stubs.c |  2 --
 3 files changed, 68 insertions(+), 2 deletions(-)
 create mode 100644 emul.c

diff --git a/Makefile b/Makefile
index 3a8d665..b561940 100644
--- a/Makefile
+++ b/Makefile
@@ -69,6 +69,7 @@ TARGET := rump-kernel
 SUBDIRS := lib xenbus console
 
 src-$(CONFIG_BLKFRONT) += blkfront.c
+src-y += emul.c
 src-y += events.c
 src-$(CONFIG_FBFRONT) += fbfront.c
 src-y += gntmap.c
diff --git a/emul.c b/emul.c
new file mode 100644
index 0000000..9063dd5
--- /dev/null
+++ b/emul.c
@@ -0,0 +1,67 @@
+/* Copyright (c) 2013 Antti Kantee.  See COPYING */
+
+/*
+ * Emulate a bit of mmap.  Currently just MAP_ANON
+ * and MAP_FILE+PROT_READ are supported.  For files, it's not true
+ * mmap, but should cover a good deal of the cases anyway.
+ */
+
+/* for libc namespace */
+#define mmap _mmap
+
+#include <sys/cdefs.h>
+#include <sys/mman.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <mini-os/os.h> /* for PAGE_SIZE */
+
+void *
+mmap(void *addr, size_t len, int prot, int flags, int fd, off_t off)
+{
+	void *v;
+	ssize_t nn;
+	int error;
+
+	if ((fd != -1 && prot != PROT_READ) || addr != NULL) {
+		errno = ENOTSUP;
+		return MAP_FAILED;
+	}
+
+	if ((error = posix_memalign(&v, len, PAGE_SIZE)) != 0) {
+		errno = error;
+		return MAP_FAILED;
+	}
+
+	if (flags & MAP_ANON)
+		return v;
+
+	if ((nn = pread(fd, v, len, off)) == -1) {
+		error = errno;
+		free(v);
+		errno = error;
+		return MAP_FAILED;
+	}
+	return v;
+}
+#undef mmap
+__weak_alias(mmap,_mmap);
+
+int
+madvise(void *addr, size_t len, int adv)
+{
+
+	/* thanks for the advise, pal */
+	return 0;
+}
+
+int
+munmap(void *addr, size_t len)
+{
+
+	free(addr);
+	return 0;
+}
diff --git a/libc_stubs.c b/libc_stubs.c
index 0e9fb9d..570e03c 100644
--- a/libc_stubs.c
+++ b/libc_stubs.c
@@ -27,8 +27,6 @@ STUB(__sigprocmask14);
 STUB(_exit);
 STUB(_lwp_kill);
 STUB(_lwp_self);
-STUB(_mmap);
-STUB(munmap);
 STUB(__wait450);
 STUB(__fork);
 
-- 
2.39.5