Alter how tmux handles the working directory to internally use file descriptors

rather than strings.

- Each session still has a current working directory.

- New sessions still get their working directory from the client that created
  them or its attached session if any.

- New windows are created by default in the session working directory.

- The -c flag to new, neww, splitw allows the working directory to be
  overridden.

- The -c flag to attach let's the session working directory be changed.

- The default-path option has been removed.

To get the equivalent to default-path '.', do:

        bind c neww -c $PWD

To get the equivalent of default-path '', do:

        bind c neww -c '#{pane_current_path}'

The equivalent of default-path '~' is left as an exercise for the reader.

This also changes the client identify protocol to be a set of messages rather
than one as well as some other changes that should make it easier to make
backwards-compatible protocol changes in future.

1 files changed, 45 insertions, 29 deletions

diff --git a/cmd-new-session.c b/cmd-new-session.c
index 38c79a6d..3ce24397 100644
--- a/cmd-new-session.c
+++ b/cmd-new-session.c
@@ -18,6 +18,8 @@
 
 #include <sys/types.h>
 
+#include <errno.h>
+#include <fcntl.h>
 #include <pwd.h>
 #include <stdlib.h>
 #include <string.h>
@@ -47,18 +49,15 @@ enum cmd_retval
 cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 {
 	struct args		*args = self->args;
-	struct client		*c = cmdq->client;
+	struct client		*c = cmdq->client, *c0;
 	struct session		*s, *groupwith;
 	struct window		*w;
 	struct environ		 env;
 	struct termios		 tio, *tiop;
-	struct passwd		*pw;
-	const char		*newname, *target, *update, *base, *cwd;
-	const char		*errstr, *template;
+	const char		*newname, *target, *update, *errstr, *template;
 	char			*cmd, *cause, *cp;
-	int			 detached, idx;
+	int			 detached, already_attached, idx, cwd, fd = -1;
 	u_int			 sx, sy;
-	int			 already_attached;
 	struct format_tree	*ft;
 
 	if (args_has(args, 't') && (args->argc != 0 || args_has(args, 'n'))) {
@@ -75,7 +74,7 @@ cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 		if (session_find(newname) != NULL) {
 			if (args_has(args, 'A')) {
 				return (cmd_attach_session(cmdq, newname,
-				    args_has(args, 'D'), 0));
+				    args_has(args, 'D'), 0, NULL));
 			}
 			cmdq_error(cmdq, "duplicate session: %s", newname);
 			return (CMD_RETURN_ERROR);
@@ -100,6 +99,31 @@ cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 	if (c != NULL && c->session != NULL)
 		already_attached = 1;
 
+	/* Get the new session working directory. */
+	if (args_has(args, 'c')) {
+		ft = format_create();
+		if ((c0 = cmd_find_client(cmdq, NULL, 1)) != NULL)
+			format_client(ft, c0);
+		cp = format_expand(ft, args_get(args, 'c'));
+		format_free(ft);
+
+		fd = open(cp, O_RDONLY|O_DIRECTORY);
+		free(cp);
+		if (fd == -1) {
+			cmdq_error(cmdq, "bad working directory: %s",
+			    strerror(errno));
+			return (CMD_RETURN_ERROR);
+		}
+		cwd = fd;
+	} else if (c->session == NULL)
+		cwd = c->cwd;
+	else if ((c0 = cmd_current_client(cmdq)) != NULL)
+		cwd = c0->session->cwd;
+	else {
+		fd = open(".", O_RDONLY);
+		cwd = fd;
+	}
+
 	/*
 	 * Save the termios settings, part of which is used for new windows in
 	 * this session.
@@ -121,26 +145,10 @@ cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 		if (server_client_open(c, NULL, &cause) != 0) {
 			cmdq_error(cmdq, "open terminal failed: %s", cause);
 			free(cause);
-			return (CMD_RETURN_ERROR);
+			goto error;
 		}
 	}
 
-	/* Get the new session working directory. */
-	if (c != NULL && c->cwd != NULL)
-		base = c->cwd;
-	else {
-		pw = getpwuid(getuid());
-		if (pw->pw_dir != NULL && *pw->pw_dir != '\0')
-			base = pw->pw_dir;
-		else
-			base = "/";
-	}
-	if (args_has(args, 'c'))
-		cwd = args_get(args, 'c');
-	else
-		cwd = options_get_string(&global_s_options, "default-path");
-	cwd = cmd_default_path(base, base, cwd);
-
 	/* Find new session size. */
 	if (c != NULL) {
 		sx = c->tty.sx;
@@ -153,14 +161,14 @@ cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 		sx = strtonum(args_get(args, 'x'), 1, USHRT_MAX, &errstr);
 		if (errstr != NULL) {
 			cmdq_error(cmdq, "width %s", errstr);
-			return (CMD_RETURN_ERROR);
+			goto error;
 		}
 	}
 	if (detached && args_has(args, 'y')) {
 		sy = strtonum(args_get(args, 'y'), 1, USHRT_MAX, &errstr);
 		if (errstr != NULL) {
 			cmdq_error(cmdq, "height %s", errstr);
-			return (CMD_RETURN_ERROR);
+			goto error;
 		}
 	}
 	if (sy > 0 && options_get_number(&global_s_options, "status"))
@@ -190,7 +198,7 @@ cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 	if (s == NULL) {
 		cmdq_error(cmdq, "create session failed: %s", cause);
 		free(cause);
-		return (CMD_RETURN_ERROR);
+		goto error;
 	}
 	environ_free(&env);
 
@@ -241,8 +249,8 @@ cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 			template = NEW_SESSION_TEMPLATE;
 
 		ft = format_create();
-		if ((c = cmd_find_client(cmdq, NULL, 1)) != NULL)
-			format_client(ft, c);
+		if ((c0 = cmd_find_client(cmdq, NULL, 1)) != NULL)
+			format_client(ft, c0);
 		format_session(ft, s);
 
 		cp = format_expand(ft, template);
@@ -254,5 +262,13 @@ cmd_new_session_exec(struct cmd *self, struct cmd_q *cmdq)
 
 	if (!detached)
 		cmdq->client_exit = 0;
+
+	if (fd != -1)
+		close(fd);
 	return (CMD_RETURN_NORMAL);
+
+error:
+	if (fd != -1)
+		close(fd);
+	return (CMD_RETURN_ERROR);
 }