2 files changed, 81 insertions, 12 deletions

diff --git a/lib9p/include/lib9p/srv.h b/lib9p/include/lib9p/srv.h
index 11c1fac..d79e7db 100644
--- a/lib9p/include/lib9p/srv.h
+++ b/lib9p/include/lib9p/srv.h
@@ -38,16 +38,19 @@ struct lib9p_srv_file;
 struct lib9p_srv_io;
 
 struct lib9p_srv_file_vtable {
-	/* all */
+	/* all - resource management */
+	struct lib9p_srv_file *(*clone  )(struct lib9p_srv_ctx *, struct lib9p_srv_file *);
+	void                   (*free   )(struct lib9p_srv_ctx *, struct lib9p_srv_file *);
+
+	/* all - syscalls */
 	struct lib9p_srv_io   *(*io     )(struct lib9p_srv_ctx *, struct lib9p_srv_file *,
 	                                  lib9p_o_t flags);
 	struct lib9p_stat      (*stat   )(struct lib9p_srv_ctx *, struct lib9p_srv_file *);
 	void                   (*wstat  )(struct lib9p_srv_ctx *, struct lib9p_srv_file *,
 	                                  struct lib9p_stat new);
 	void                   (*remove )(struct lib9p_srv_ctx *, struct lib9p_srv_file *);
-	void                   (*free   )(struct lib9p_srv_ctx *, struct lib9p_srv_file *); /* optional */
 
-	/* dir */
+	/* directories */
 	struct lib9p_srv_file *(*dopen  )(struct lib9p_srv_ctx *, struct lib9p_srv_file *,
 	                                 char *childname);
 	struct lib9p_srv_file *(*dcreate)(struct lib9p_srv_ctx *, struct lib9p_srv_file *,
@@ -77,7 +80,6 @@ struct lib9p_srv_file {
 
 	/* Managed by srv.c */
 	struct lib9p_srv_file           *_parent_dir;
-	struct lib9p_srv_file           *_refcount;
 
 	/* This is where your implementation data goes.  */
 	char                             data[0];
diff --git a/lib9p/srv.c b/lib9p/srv.c
index 84b3ae8..5af0971 100644
--- a/lib9p/srv.c
+++ b/lib9p/srv.c
@@ -515,6 +515,7 @@ static void handle_Tattach(struct _lib9p_srv_req *ctx,
 	}
 
 	struct lib9p_srv_file *rootdir = srv->rootdir(&ctx->ctx, req->aname.utf8);
+	assert((rootdir == NULL) == lib9p_ctx_has_error(&ctx->ctx.basectx));
 	if (lib9p_ctx_has_error(&ctx->ctx.basectx))
 		return;
 	rootdir->_parent_dir = rootdir;
@@ -522,8 +523,7 @@ static void handle_Tattach(struct _lib9p_srv_req *ctx,
 	if (!fidmap_store(&ctx->parent_sess->fids, req->fid, rootdir)) {
 		lib9p_error(&ctx->ctx.basectx,
 		            LINUX_EMFILE, "too many open files");
-		if (rootdir->vtable->free)
-			rootdir->vtable->free(&ctx->ctx, rootdir);
+		rootdir->vtable->free(&ctx->ctx, rootdir);
 		return;
 	}
 
@@ -558,8 +558,70 @@ static void handle_Twalk(struct _lib9p_srv_req *ctx,
 	assert(req);
 	assert(resp);
 
-	lib9p_error(&ctx->ctx.basectx,
-	            LINUX_EOPNOTSUPP, "walk not yet implemented");
+	struct lib9p_srv_file **dirpp = fidmap_load(&ctx->parent_sess->fids, req->fid);
+	if (!dirpp) {
+		lib9p_errorf(&ctx->ctx.basectx,
+		             LINUX_EBADF, "bad file number %"PRIu32, req->fid);
+		return;
+	}
+	if (req->newfid != req->fid && fidmap_load(&ctx->parent_sess->fids, req->newfid)) {
+		lib9p_error(&ctx->ctx.basectx,
+		            LINUX_EBADF, "FID already in use");
+		return;
+	}
+
+	struct lib9p_srv_file *dirp;
+	if (req->newfid == req->fid)
+		dirp = *dirpp;
+	else {
+		dirp = (*dirpp)->vtable->clone(&ctx->ctx, *dirpp);
+		assert((dirp == NULL) == lib9p_ctx_has_error(&ctx->ctx.basectx));
+		if (lib9p_ctx_has_error(&ctx->ctx.basectx))
+			return;
+	}
+
+	resp->wqid = (struct lib9p_qid *)(&resp[1]);
+	for (resp->nwqid = 0; resp->nwqid < req->nwname; resp->nwqid++) {
+		struct lib9p_srv_file *memberp;
+		if (strcmp(req->wname[resp->nwqid].utf8, "..")) {
+			memberp = dirp->_parent_dir;
+		} else {
+			struct lib9p_stat stat = dirp->vtable->stat(&ctx->ctx, dirp);
+			if (lib9p_ctx_has_error(&ctx->ctx.basectx))
+				break;
+			if (!(stat.file_qid.type & LIB9P_QT_DIR) || !(stat.file_mode & LIB9P_DM_DIR)) {
+				lib9p_error(&ctx->ctx.basectx,
+				            LINUX_ENOTDIR, "not a directory");
+				break;
+			}
+
+			memberp = dirp->vtable->dopen(&ctx->ctx, dirp, req->wname[resp->nwqid].utf8);
+			assert((memberp == NULL) == lib9p_ctx_has_error(&ctx->ctx.basectx));
+			if (lib9p_ctx_has_error(&ctx->ctx.basectx))
+				break;
+		}
+
+		struct lib9p_stat stat = memberp->vtable->stat(&ctx->ctx, memberp);
+		if (lib9p_ctx_has_error(&ctx->ctx.basectx))
+			break;
+		resp->wqid[resp->nwqid] = stat.file_qid;
+
+		dirp->vtable->free(&ctx->ctx, dirp);
+		dirp = memberp;
+	}
+	if (resp->nwqid == req->nwname) {
+		if (req->newfid == req->fid)
+			*dirpp = dirp;
+		else
+			if (!fidmap_store(&ctx->parent_sess->fids, req->newfid, dirp)) {
+				lib9p_error(&ctx->ctx.basectx,
+				            LINUX_EMFILE, "too many open files");
+				dirp->vtable->free(&ctx->ctx, dirp);
+			}
+	} else if (resp->nwqid > 0) {
+		ctx->ctx.basectx.err_num = 0;
+		ctx->ctx.basectx.err_msg[0] = '\0';
+	}
 }
 
 static void handle_Topen(struct _lib9p_srv_req *ctx,
@@ -620,8 +682,7 @@ static void handle_Tclunk(struct _lib9p_srv_req *ctx,
 		return;
 	}
 
-	if ((*filepp)->vtable->free)
-		(*filepp)->vtable->free(&ctx->ctx, *filepp);
+	(*filepp)->vtable->free(&ctx->ctx, *filepp);
 	fidmap_del(&ctx->parent_sess->fids, req->fid);
 }
 
@@ -643,8 +704,14 @@ static void handle_Tstat(struct _lib9p_srv_req *ctx,
 	assert(req);
 	assert(resp);
 
-	lib9p_error(&ctx->ctx.basectx,
-	            LINUX_EOPNOTSUPP, "stat not yet implemented");
+	struct lib9p_srv_file **filepp = fidmap_load(&ctx->parent_sess->fids, req->fid);
+	if (!filepp) {
+		lib9p_errorf(&ctx->ctx.basectx,
+		             LINUX_EBADF, "bad file number %"PRIu32, req->fid);
+		return;
+	}
+
+	resp->stat = (*filepp)->vtable->stat(&ctx->ctx, *filepp);
 }
 
 static void handle_Twstat(struct _lib9p_srv_req *ctx,