rename: RENAME_NOREPLACE

kernel-src/fs/ext2.c

@@ -1871,6 +1871,12 @@ static int ext2_rename(vnode_t *sourcedir, vnode_t *source, char *oldname, vnode
 	ext2node_t *ext2_replaced_node = (ext2node_t *)replaced_vnode;
 
 	if (replaced_vnode) {
+		if (flags & RENAME_NOREPLACE) {
+			VOP_UNLOCK(replaced_vnode);
+			VOP_RELEASE(replaced_vnode);
+			return EEXIST;
+		}
+
 		// we are replacing an existing link
 		// do some checks expected by posix
 		if (source->type != V_TYPE_DIR && replaced_vnode->type == V_TYPE_DIR) {

kernel-src/fs/fat/fatfs.c

@@ -738,6 +738,12 @@ static int fatfs_rename(vnode_t *vsource_dir, vnode_t *vsource, char *old_name,
 	target = (fatnode_t *)vtarget;
 
 	if (target) {
+		if (flags & RENAME_NOREPLACE) {
+			VOP_UNLOCK(vtarget);
+			VOP_RELEASE(vtarget);
+			return EEXIST;
+		}
+
 		// we are replacing an existing link
 		// do some checks expected by posix
 		if (vsource->type != V_TYPE_DIR && vtarget->type == V_TYPE_DIR) {

kernel-src/fs/tmpfs.c

@@ -352,6 +352,9 @@ static int tmpfs_rename(vnode_t *source, vnode_t *sourcefile, char *oldname, vno
 		oldnode = v;
 
 	if (oldnode) {
+		if (flags & RENAME_NOREPLACE)
+			return EEXIST;
+
 		// we are replacing an existing link
 		// do some checks expected by posix
 		if (sourcefile->type != V_TYPE_DIR && oldnode->type == V_TYPE_DIR)

kernel-src/include/kernel/abi.h

@@ -84,6 +84,8 @@ typedef struct {
 #define AT_SYMLINK_NOFOLLOW 0x100
 #define AT_EMPTY_PATH 0x1000
 
+#define RENAME_NOREPLACE 0x1
+
 #define AF_LOCAL 1
 #define AF_INET 2
 

kernel-src/sys/syscalls/renameat.c

@@ -3,13 +3,15 @@
 #include <string.h>
 #include <logging.h>
 
+#define RENAMEAT_KNOWN_FLAGS RENAME_NOREPLACE
+
 syscallret_t syscall_renameat(context_t *context, int olddirfd, char *uoldpath, int newdirfd, char *unewpath, unsigned int flags) {
 	syscallret_t ret = {
 		.ret = -1
 	};
 
-	if (flags)
-		printf("renameat: unknown %x\n", flags);
+	if (flags & ~RENAMEAT_KNOWN_FLAGS)
+		printf("renameat: unknown %x\n", flags & ~RENAMEAT_KNOWN_FLAGS);
 
 	size_t oldpathlen;
 	size_t newpathlen;