lib9p: Implemnt Topen, add permission checks in Twalk

3 files changed, 36 insertions, 37 deletions

diff --git a/lib9p/include/lib9p/9p.generated.h b/lib9p/include/lib9p/9p.generated.h
index 6248ec7..584960c 100644
--- a/lib9p/include/lib9p/9p.generated.h
+++ b/lib9p/include/lib9p/9p.generated.h
@@ -80,7 +80,7 @@ typedef uint32_t lib9p_dm_t;
 #define   LIB9P_DM_OTHER_W       ((lib9p_dm_t)(1<<1))
 #define   LIB9P_DM_OTHER_X       ((lib9p_dm_t)(1<<0))
 
-#define   LIB9P_DM_PERM          ((lib9p_dm_t)(0777))
+#define   LIB9P_DM_PERM_MASK     ((lib9p_dm_t)(0777))
 
 typedef uint8_t lib9p_qt_t;
 
@@ -125,19 +125,21 @@ struct lib9p_stat {
 
 typedef uint8_t lib9p_o_t;
 
-/* unused                 ((lib9p_o_t)(1<<7)) */
-#define   LIB9P_O_RCLOSE  ((lib9p_o_t)(1<<6))
-/* unused                 ((lib9p_o_t)(1<<5)) */
-#define   LIB9P_O_TRUNC   ((lib9p_o_t)(1<<4))
-/* unused                 ((lib9p_o_t)(1<<3)) */
-/* unused                 ((lib9p_o_t)(1<<2)) */
-#define   LIB9P_O_rwx_1   ((lib9p_o_t)(1<<1))
-#define   LIB9P_O_rwx_0   ((lib9p_o_t)(1<<0))
-
-#define   LIB9P_O_READ    ((lib9p_o_t)(0))
-#define   LIB9P_O_WRITE   ((lib9p_o_t)(1))
-#define   LIB9P_O_RDWR    ((lib9p_o_t)(2))
-#define   LIB9P_O_EXEC    ((lib9p_o_t)(3))
+/* unused                    ((lib9p_o_t)(1<<7)) */
+#define   LIB9P_O_RCLOSE     ((lib9p_o_t)(1<<6))
+/* unused                    ((lib9p_o_t)(1<<5)) */
+#define   LIB9P_O_TRUNC      ((lib9p_o_t)(1<<4))
+/* unused                    ((lib9p_o_t)(1<<3)) */
+/* unused                    ((lib9p_o_t)(1<<2)) */
+#define   LIB9P_O_mode_1     ((lib9p_o_t)(1<<1))
+#define   LIB9P_O_mode_0     ((lib9p_o_t)(1<<0))
+
+#define   LIB9P_O_READ       ((lib9p_o_t)(0))
+#define   LIB9P_O_WRITE      ((lib9p_o_t)(1))
+#define   LIB9P_O_RDWR       ((lib9p_o_t)(2))
+#define   LIB9P_O_EXEC       ((lib9p_o_t)(3))
+#define   LIB9P_O_MODE_MASK  ((lib9p_o_t)(0b00000011))
+#define   LIB9P_O_FLAG_MASK  ((lib9p_o_t)(0b11111100))
 #endif /* defined(CONFIG_9P_ENABLE_9P2000) || defined(CONFIG_9P_ENABLE_9P2000_e) || defined(CONFIG_9P_ENABLE_9P2000_u) */
 
 /* messages *******************************************************************/
diff --git a/lib9p/include/lib9p/9p.h b/lib9p/include/lib9p/9p.h
index 3ad52f1..c3c6a8b 100644
--- a/lib9p/include/lib9p/9p.h
+++ b/lib9p/include/lib9p/9p.h
@@ -41,6 +41,12 @@ struct lib9p_ctx {
 	char                    err_msg[CONFIG_9P_MAX_ERR_SIZE];
 };
 
+static void lib9p_ctx_clear_error(struct lib9p_ctx *ctx) {
+	assert(ctx);
+	ctx->err_num = 0;
+	ctx->err_msg[0] = '\0';
+}
+
 static bool lib9p_ctx_has_error(struct lib9p_ctx *ctx) {
 	assert(ctx);
 	return ctx->err_num || ctx->err_msg[0];
diff --git a/lib9p/include/lib9p/srv.h b/lib9p/include/lib9p/srv.h
index d79e7db..5df6b1a 100644
--- a/lib9p/include/lib9p/srv.h
+++ b/lib9p/include/lib9p/srv.h
@@ -35,7 +35,6 @@ static inline int lib9p_srv_acknowledge_flush(struct lib9p_srv_ctx *ctx) {
 /* vtables you must implement *************************************************/
 
 struct lib9p_srv_file;
-struct lib9p_srv_io;
 
 struct lib9p_srv_file_vtable {
 	/* all - resource management */
@@ -43,28 +42,26 @@ struct lib9p_srv_file_vtable {
 	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 *,
+	uint32_t               (*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 *);
 
-	/* directories */
+	/* directories - base */
 	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 *,
 	                                 char *childname,
 	                                 lib9p_dm_t perm, lib9p_o_t flags);
-};
 
-struct lib9p_srv_io_dir_vtable {
+	/* directories - once opened */
 	size_t                 (*readdir)(struct lib9p_srv_ctx *, struct lib9p_srv_io_dir *,
 	                                  struct lib9p_stat *buf, size_t count,
 	                                  size_t offset);
-};
 
-struct lib9p_srv_io_file_vtable {
+	/* non-directories - once opened */
 	uint32_t               (*pread  )(struct lib9p_srv_ctx *, struct lib9p_srv_io_file *,
 	                                  void *buf, uint32_t count,
 	                                  uint64_t offset);
@@ -78,25 +75,19 @@ struct lib9p_srv_io_file_vtable {
 struct lib9p_srv_file {
 	struct lib9p_srv_file_vtable    *vtable;
 
-	/* Managed by srv.c */
-	struct lib9p_srv_file           *_parent_dir;
-
-	/* This is where your implementation data goes.  */
-	char                             data[0];
-};
-
-struct lib9p_srv_io {
-	union {
-		struct lib9p_srv_io_dir_vtable   *dir;
-		struct lib9p_srv_io_file_vtable  *file;
-	}                        vtable;
+	/* Managed by srv.c, but should be cloned by ->vtable->clone().  */
+	struct lib9p_srv_file           *_parent_dir; /* clone this
 
-	struct lib9p_srv_file   *file;
-	struct lib9p_qid         qid;
-	uint32_t                 iounit;
+	/* Managed by srv.c, and should be initialized to 0 by ->vtable->clone().  */
+	/* ref type 1: an entry in fidmap
+	 * ref type 2: ->_parent_dir of another file */
+	struct lib9p_srv_file           *_refcount;
+	lib9p_o_t                        _io_flags;
+	struct lib9p_qid                 _io_qid;
+	uint32_t                         _io_unit;
 
 	/* This is where your implementation data goes.  */
-	char                     data[0];
+	char                             data[0];
 };
 
 /* main server entrypoints ****************************************************/