fix several issues relating to elf and registers and add mmap

src/sys/syscalls/libclog.c

@@ -17,7 +17,7 @@ syscallret syscall_libc_log(char* str){
 
 	strcpy(buf, str);
 
-	printf("%s", str);
+	printf("%s\n", str);
 
 	ret.errno = 0;
 	ret.ret = 0;

src/sys/syscalls/mmap.c

@@ -0,0 +1,97 @@
+#include <kernel/syscalls.h>
+#include <kernel/vmm.h>
+#include <sys/types.h>
+#include <errno.h>
+
+// linux abi
+
+#define PROT_NONE  0x00
+#define PROT_READ  0x01
+#define PROT_WRITE 0x02
+#define PROT_EXEC  0x04
+
+#define MAP_FILE    0x00
+#define MAP_SHARED    0x01
+#define MAP_PRIVATE   0x02
+#define MAP_FIXED     0x10
+#define MAP_ANON      0x20
+#define MAP_ANONYMOUS 0x20
+#define MAP_NORESERVE 0x4000
+
+#define MS_ASYNC 0x01
+#define MS_INVALIDATE 0x02
+#define MS_SYNC 0x04
+
+#define MCL_CURRENT 0x01
+#define MCL_FUTURE 0x02
+
+#define POSIX_MADV_NORMAL 0
+#define POSIX_MADV_RANDOM 1
+#define POSIX_MADV_SEQUENTIAL 2
+#define POSIX_MADV_WILLNEED 3
+#define POSIX_MADV_DONTNEED 4
+
+#define MADV_NORMAL 0
+#define MADV_RANDOM 1
+#define MADV_SEQUENTIAL 2
+#define MADV_WILLNEED 3
+#define MADV_DONTNEED 4
+#define MADV_FREE 8
+
+#define MREMAP_MAYMOVE 1
+#define MREMAP_FIXED 2
+
+#define MFD_CLOEXEC 1U
+#define MFD_ALLOW_SEALING 2U
+
+syscallret syscall_mmap(void* hint, size_t len, int prot, int flags, int fd, off_t offset){
+	syscallret retv;
+	
+	retv.ret = -1;
+	retv.errno = 0;
+
+	if(len == 0 || hint > USER_SPACE_END){
+		retv.errno = EINVAL;
+		return retv;
+	}
+
+	if(flags != (MAP_ANON | MAP_PRIVATE)){
+		retv.errno = ENOSYS;
+		return retv;
+		
+	}
+	
+	size_t mmuflags = 0;
+
+	if(prot & PROT_READ)
+		mmuflags |= ARCH_MMU_MAP_READ;
+	
+	if(prot & PROT_WRITE)
+		mmuflags |= ARCH_MMU_MAP_WRITE;
+	
+	if(!prot & PROT_EXEC)
+		mmuflags |= ARCH_MMU_MAP_NOEXEC;
+	
+	mmuflags |= ARCH_MMU_MAP_USER;
+
+	size_t plen = len / PAGE_SIZE + (len % PAGE_SIZE ? 1 : 0);
+
+	void* ret = NULL;
+
+	if(hint)
+		ret = vmm_allocnowat(hint, mmuflags, plen) ? hint : NULL; // TODO demand page
+	
+	if(!ret && !(flags & MAP_FIXED))
+		ret = vmm_allocfrom(USER_ALLOC_START, mmuflags, len);
+
+	if(!ret){
+		retv.errno = ENOMEM;
+		if(flags & MAP_ANON)
+			memset(ret, 0, plen);
+	}
+	else
+		retv.ret = ret;
+
+	return retv;
+
+}