Import a basic implementation of mmap() and munmap()

include/errno.h

@@ -9,6 +9,7 @@
 
 
 /* constants */
+# define EPERM		1
 # define EBADF		9
 # define ENOMEM		12
 # define ENODEV		19

include/stdint.h

@@ -57,6 +57,31 @@ typedef unsigned long uintptr_t;
 
 typedef unsigned long size_t;
 
+
+/* constants */
+# define INT8_MAX	0x7f
+# define INT16_MAX	0x7fff
+# define INT32_MAX	0x7fffffff
+# define INT64_MAX	0x7fffffffffffffff
+
+# define INT8_MIN	(-INT8_MAX - 1)
+# define INT16_MIN	(-INT16_MAX - 1)
+# define INT32_MIN	(-INT32_MAX - 1)
+# define INT64_MIN	(-INT64_MAX - 1)
+
+# define UINT8_MAX	0xff
+# define UINT16_MAX	0xffff
+# define UINT32_MAX	0xffffffff
+# define UINT64_MAX	0xffffffffffffffff
+
+# ifndef ULONG_MAX
+#  ifdef _LP64 /* FIXME probably sometimes wrong */
+#   define ULONG_MAX 0xffffffffffffffff
+#  else
+#   define ULONG_MAX 0xffffffff
+#  endif
+# endif
+
 # ifndef SIZE_MAX
 #  define SIZE_MAX	ULONG_MAX
 # endif

include/stdlib.h

@@ -15,6 +15,7 @@
 void abort(void);
 int abs(int x);
 uint32_t arc4random(void);
+void * calloc(size_t nmemb, size_t size);
 void exit(int status);
 void free(void * ptr);
 long labs(long x);

include/sys/mman.h

@@ -0,0 +1,48 @@
+/* $Id$ */
+/* Copyright (c) 2018 Pierre Pronchery <khorben@defora.org> */
+/* This file is part of DeforaOS uKernel */
+
+
+
+#ifndef UKERNEL_SYS_MMAN_H
+# define UKERNEL_SYS_MMAN_H
+
+
+/* types */
+# ifndef mode_t
+#  define mode_t mode_t
+typedef unsigned int mode_t;
+# endif
+# ifndef off_t
+#  define off_t off_t
+typedef long long off_t;
+# endif
+# ifndef size_t
+#  define size_t size_t
+typedef unsigned long size_t;
+# endif
+
+
+/* constants */
+# define MAP_FAILED	((void *)-1)
+
+# define MAP_SHARED	0x0001
+# define MAP_PRIVATE	0x0002
+# define MAP_FIXED	0x0010
+# define MAP_ANONYMOUS	0x1000
+
+# define PROT_NONE	0x0
+# define PROT_READ	0x1
+# define PROT_WRITE	0x2
+# define PROT_EXEC	0x4
+
+
+/* functions */
+int mlock(const void * addr, size_t length);
+void * mmap(void * addr, size_t length, int prot, int flags, int fd,
+		off_t offset);
+int mprotect(void * addr, size_t length, int prot);
+int munlock(const void * addr, size_t length);
+int munmap(void * addr, size_t length);
+
+#endif /* !UKERNEL_SYS_MMAN_H */

include/sys/project.conf

@@ -1 +1 @@
-dist=Makefile,types.h
+dist=Makefile,mman.h,types.h

src/lib/project.conf

@@ -7,7 +7,7 @@ dist=Makefile,ssp.h
 
 [libuKernel]
 type=library
-sources=ctype.c,errno.c,ssp.c,stdio.c,stdlib.c,string.c,unistd.c
+sources=ctype.c,errno.c,ssp.c,stdio.c,stdlib.c,string.c,sys/mman.c,unistd.c
 
 [ctype.c]
 depends=../../include/ctype.h
@@ -26,3 +26,6 @@ depends=../../include/stdlib.h,../../include/unistd.h
 
 [string.c]
 depends=../../include/string.h
+
+[sys/mman.c]
+depends=../../include/sys/mman.h

src/lib/stdlib.c

@@ -4,7 +4,9 @@
 
 
 
+#include <stdint.h>
 #include <unistd.h>
+#include <string.h>
 #include <limits.h>
 #include <errno.h>
 #include <stdlib.h>
@@ -48,6 +50,25 @@ uint32_t arc4random(void)
 }
 
 
+/* calloc */
+void * calloc(size_t nmemb, size_t size)
+{
+	void * ptr;
+	size_t sz;
+
+	if(nmemb != 0 && size != 0 && SIZE_MAX / nmemb < size)
+	{
+		errno = ENOMEM;
+		return NULL;
+	}
+	sz = nmemb * size;
+	if((ptr = malloc(sz)) == NULL)
+		return NULL;
+	memset(ptr, 0, sz);
+	return ptr;
+}
+
+
 /* exit */
 void exit(int status)
 {

src/lib/sys/mman.c

@@ -0,0 +1,64 @@
+/* $Id$ */
+/* Copyright (c) 2018 Pierre Pronchery <khorben@defora.org> */
+/* This file is part of DeforaOS uKernel */
+
+
+
+#include <stdlib.h>
+#include <errno.h>
+#include <sys/mman.h>
+
+
+/* mmap */
+void * mmap(void * addr, size_t length, int prot, int flags, int fd,
+		off_t offset)
+{
+	void * ret;
+
+	/* enforce W^X */
+	if((prot & (PROT_WRITE | PROT_EXEC)) == (PROT_WRITE | PROT_EXEC))
+	{
+		errno = EPERM;
+		return MAP_FAILED;
+	}
+	/* flags */
+	if((flags & MAP_PRIVATE) != MAP_PRIVATE)
+	{
+		errno = EINVAL;
+		return MAP_FAILED;
+	}
+	if((flags & MAP_ANONYMOUS) == MAP_ANONYMOUS)
+		ret = calloc(1, length);
+	else
+		ret = malloc(length);
+	return (ret != NULL) ? ret : MAP_FAILED;
+}
+
+
+/* mprotect */
+int mprotect(void * addr, size_t length, int prot)
+{
+	if(addr == NULL || length == 0)
+	{
+		errno = EINVAL;
+		return -1;
+	}
+	/* FIXME really implement */
+	return 0;
+}
+
+
+/* munmap */
+int munmap(void * addr, size_t length)
+{
+	(void) length;
+
+	if(length == 0)
+	{
+		errno = EINVAL;
+		return -1;
+	}
+	/* FIXME check the length? */
+	free(addr);
+	return 0;
+}