Add a command queue to standardize and simplify commands that call other

commands and allow a command to block execution of subsequent commands. This
allows run-shell and if-shell to be synchronous which has been much requested.

Each client has a default command queue and commands are consumed one at a time
from it. A command may suspend execution from the queue by returning
CMD_RETURN_WAIT and then resume it by calling cmd_continue() - for example
run-shell does this from the callback that is fired after the job is freed.

When the command queue becomes empty, command clients are automatically exited
(unless attaching). A callback is also fired - this is used for nested commands
in, for example, if-shell which can block execution of the client's cmdq until
a new cmdq becomes empty.

Also merge all the old error/info/print functions together and lose the old
curclient/cmdclient distinction - a cmdq is bound to one client (or none if in
the configuration file), this is a command client if c->session is NULL
otherwise an attached client.

Makefile.am

@@ -104,6 +104,7 @@ dist_tmux_SOURCES = \
 	cmd-new-window.c \
 	cmd-paste-buffer.c \
 	cmd-pipe-pane.c \
+	cmd-queue.c \
 	cmd-refresh-client.c \
 	cmd-rename-session.c \
 	cmd-rename-window.c \

cfg.c

@@ -27,80 +27,27 @@
 
 #include "tmux.h"
 
-/*
- * Config file parser. Pretty quick and simple, each line is parsed into a
- * argv array and executed as a command.
- */
-
-void printflike2 cfg_print(struct cmd_ctx *, const char *, ...);
-void printflike2 cfg_error(struct cmd_ctx *, const char *, ...);
-
-char			*cfg_cause;
+struct cmd_q		*cfg_cmd_q;
 int			 cfg_finished;
-int	 		 cfg_references;
+int			 cfg_references;
 struct causelist	 cfg_causes;
 
-void printflike2
-cfg_print(unused struct cmd_ctx *ctx, unused const char *fmt, ...)
-{
-}
-
-void printflike2
-cfg_error(unused struct cmd_ctx *ctx, const char *fmt, ...)
-{
-	va_list	ap;
-
-	va_start(ap, fmt);
-	xvasprintf(&cfg_cause, fmt, ap);
-	va_end(ap);
-}
-
-void printflike2
-cfg_add_cause(struct causelist *causes, const char *fmt, ...)
-{
-	char	*cause;
-	va_list	 ap;
-
-	va_start(ap, fmt);
-	xvasprintf(&cause, fmt, ap);
-	va_end(ap);
-
-	ARRAY_ADD(causes, cause);
-}
-
-/*
- * Load configuration file. Returns -1 for an error with a list of messages in
- * causes. Note that causes must be initialised by the caller!
- */
-enum cmd_retval
-load_cfg(const char *path, struct cmd_ctx *ctx, struct causelist *causes)
+int
+load_cfg(const char *path, struct cmd_q *cmdq, char **cause)
 {
 	FILE		*f;
-	u_int		 n;
-	char		*buf, *copy, *line, *cause;
+	u_int		 n, found;
+	char		*buf, *copy, *line, *cause1, *msg;
 	size_t		 len, oldlen;
 	struct cmd_list	*cmdlist;
-	enum cmd_retval	 retval;
 
 	if ((f = fopen(path, "rb")) == NULL) {
-		cfg_add_cause(causes, "%s: %s", path, strerror(errno));
-		return (CMD_RETURN_ERROR);
-	}
-
-	cfg_references++;
-
-	if (ctx != NULL)
-		cmd_ref_ctx(ctx);
-	else {
-		ctx = cmd_get_ctx(NULL, NULL);
-		ctx->error = cfg_error;
-		ctx->print = cfg_print;
-		ctx->info = cfg_print;
+		xasprintf(cause, "%s: %s", path, strerror(errno));
+		return (-1);
 	}
 
-	n = 0;
+	n = found = 0;
 	line = NULL;
-	retval = CMD_RETURN_NORMAL;
 	while ((buf = fgetln(f, &len))) {
 		/* Trim \n. */
 		if (buf[len - 1] == '\n')
@@ -142,61 +89,54 @@ load_cfg(const char *path, struct cmd_ctx *ctx, struct causelist *causes)
 			continue;
 		}
 
-		if (cmd_string_parse(buf, &cmdlist, &cause) != 0) {
+		/* Parse and run the command. */
+		if (cmd_string_parse(buf, &cmdlist, path, n, &cause1) != 0) {
 			free(copy);
-			if (cause == NULL)
+			if (cause1 == NULL)
 				continue;
-			cfg_add_cause(causes, "%s: %u: %s", path, n, cause);
-			free(cause);
+			xasprintf(&msg, "%s:%u: %s", path, n, cause1);
+			ARRAY_ADD(&cfg_causes, msg);
+			free(cause1);
 			continue;
 		}
 		free(copy);
+
 		if (cmdlist == NULL)
 			continue;
-
-		cfg_cause = NULL;
-		switch (cmd_list_exec(cmdlist, ctx)) {
-		case CMD_RETURN_YIELD:
-			if (retval != CMD_RETURN_ATTACH)
-				retval = CMD_RETURN_YIELD;
-			break;
-		case CMD_RETURN_ATTACH:
-			retval = CMD_RETURN_ATTACH;
-			break;
-		case CMD_RETURN_ERROR:
-		case CMD_RETURN_NORMAL:
-			break;
-		}
+		cmdq_append(cmdq, cmdlist);
 		cmd_list_free(cmdlist);
-		if (cfg_cause != NULL) {
-			cfg_add_cause(causes, "%s: %d: %s", path, n, cfg_cause);
-			free(cfg_cause);
-		}
+		found++;
 	}
-	if (line != NULL) {
-		cfg_add_cause(causes,
-		    "%s: %d: line continuation at end of file", path, n);
+	if (line != NULL)
 		free(line);
-	}
 	fclose(f);
 
-	cmd_free_ctx(ctx);
+	return (found);
+}
+
+void
+cfg_default_done(unused struct cmd_q *cmdq)
+{
+	if (--cfg_references != 0)
+		return;
+	cfg_finished = 1;
 
-	cfg_references--;
+	if (!RB_EMPTY(&sessions))
+		cfg_show_causes(RB_MIN(sessions, &sessions));
 
-	return (retval);
+	cmdq_free(cfg_cmd_q);
+	cfg_cmd_q = NULL;
 }
 
 void
-show_cfg_causes(struct session *s)
+cfg_show_causes(struct session *s)
 {
 	struct window_pane	*wp;
 	char			*cause;
 	u_int			 i;
 
 	if (s == NULL || ARRAY_EMPTY(&cfg_causes))
 		return;
-
 	wp = s->curw->window->active;
 
 	window_pane_set_mode(wp, &window_copy_mode);

client.c

@@ -188,7 +188,8 @@ client_main(int argc, char **argv, int flags)
 		 * later in server) but it is necessary to get the start server
 		 * flag.
 		 */
-		if ((cmdlist = cmd_list_parse(argc, argv, &cause)) == NULL) {
+		cmdlist = cmd_list_parse(argc, argv, NULL, 0, &cause);
+		if (cmdlist == NULL) {
 			fprintf(stderr, "%s\n", cause);
 			return (1);
 		}

cmd-attach-session.c

@@ -26,7 +26,7 @@
  * Attach existing session to the current terminal.
  */
 
-enum cmd_retval	cmd_attach_session_exec(struct cmd *, struct cmd_ctx *);
+enum cmd_retval	cmd_attach_session_exec(struct cmd *, struct cmd_q *);
 
 const struct cmd_entry cmd_attach_session_entry = {
 	"attach-session", "attach",
@@ -39,7 +39,7 @@ const struct cmd_entry cmd_attach_session_entry = {
 };
 
 enum cmd_retval
-cmd_attach_session_exec(struct cmd *self, struct cmd_ctx *ctx)
+cmd_attach_session_exec(struct cmd *self, struct cmd_q *cmdq)
 {
 	struct args	*args = self->args;
 	struct session	*s;
@@ -49,17 +49,17 @@ cmd_attach_session_exec(struct cmd *self, struct cmd_ctx *ctx)
 	u_int		 i;
 
 	if (RB_EMPTY(&sessions)) {
-		ctx->error(ctx, "no sessions");
+		cmdq_error(cmdq, "no sessions");
 		return (CMD_RETURN_ERROR);
 	}
 
-	if ((s = cmd_find_session(ctx, args_get(args, 't'), 1)) == NULL)
+	if ((s = cmd_find_session(cmdq, args_get(args, 't'), 1)) == NULL)
 		return (CMD_RETURN_ERROR);
 
-	if (ctx->cmdclient == NULL && ctx->curclient == NULL)
+	if (cmdq->client == NULL)
 		return (CMD_RETURN_NORMAL);
 
-	if (ctx->cmdclient == NULL) {
+	if (cmdq->client->session != NULL) {
 		if (args_has(self->args, 'd')) {
 			/*
 			 * Can't use server_write_session in case attaching to
@@ -69,43 +69,44 @@ cmd_attach_session_exec(struct cmd *self, struct cmd_ctx *ctx)
 				c = ARRAY_ITEM(&clients, i);
 				if (c == NULL || c->session != s)
 					continue;
-				if (c == ctx->curclient)
+				if (c == cmdq->client)
 					continue;
 				server_write_client(c, MSG_DETACH, NULL, 0);
 			}
 		}
 
-		ctx->curclient->session = s;
-		notify_attached_session_changed(ctx->curclient);
+		cmdq->client->session = s;
+		notify_attached_session_changed(cmdq->client);
 		session_update_activity(s);
-		server_redraw_client(ctx->curclient);
+		server_redraw_client(cmdq->client);
 		s->curw->flags &= ~WINLINK_ALERTFLAGS;
 	} else {
-		if (server_client_open(ctx->cmdclient, s, &cause) != 0) {
-			ctx->error(ctx, "open terminal failed: %s", cause);
+		if (server_client_open(cmdq->client, s, &cause) != 0) {
+			cmdq_error(cmdq, "open terminal failed: %s", cause);
 			free(cause);
 			return (CMD_RETURN_ERROR);
 		}
 
 		if (args_has(self->args, 'r'))
-			ctx->cmdclient->flags |= CLIENT_READONLY;
+			cmdq->client->flags |= CLIENT_READONLY;
 
 		if (args_has(self->args, 'd'))
 			server_write_session(s, MSG_DETACH, NULL, 0);
 
-		ctx->cmdclient->session = s;
-		notify_attached_session_changed(ctx->cmdclient);
-		session_update_activity(s);
-		server_write_ready(ctx->cmdclient);
-
 		update = options_get_string(&s->options, "update-environment");
-		environ_update(update, &ctx->cmdclient->environ, &s->environ);
+		environ_update(update, &cmdq->client->environ, &s->environ);
 
-		server_redraw_client(ctx->cmdclient);
+		cmdq->client->session = s;
+		notify_attached_session_changed(cmdq->client);
+		session_update_activity(s);
+		server_redraw_client(cmdq->client);
 		s->curw->flags &= ~WINLINK_ALERTFLAGS;
+
+		server_write_ready(cmdq->client);
+		cmdq->client_exit = 0;
 	}
 	recalculate_sizes();
 	server_update_socket();
 
-	return (CMD_RETURN_ATTACH);
+	return (CMD_RETURN_NORMAL);
 }

cmd-bind-key.c

@@ -28,9 +28,9 @@
  */
 
 enum cmd_retval	 cmd_bind_key_check(struct args *);
-enum cmd_retval	 cmd_bind_key_exec(struct cmd *, struct cmd_ctx *);
+enum cmd_retval	 cmd_bind_key_exec(struct cmd *, struct cmd_q *);
 
-enum cmd_retval	 cmd_bind_key_table(struct cmd *, struct cmd_ctx *, int);
+enum cmd_retval	 cmd_bind_key_table(struct cmd *, struct cmd_q *, int);
 
 const struct cmd_entry cmd_bind_key_entry = {
 	"bind-key", "bind",
@@ -56,7 +56,7 @@ cmd_bind_key_check(struct args *args)
 }
 
 enum cmd_retval
-cmd_bind_key_exec(struct cmd *self, struct cmd_ctx *ctx)
+cmd_bind_key_exec(struct cmd *self, struct cmd_q *cmdq)
 {
 	struct args	*args = self->args;
 	char		*cause;
@@ -65,16 +65,17 @@ cmd_bind_key_exec(struct cmd *self, struct cmd_ctx *ctx)
 
 	key = key_string_lookup_string(args->argv[0]);
 	if (key == KEYC_NONE) {
-		ctx->error(ctx, "unknown key: %s", args->argv[0]);
+		cmdq_error(cmdq, "unknown key: %s", args->argv[0]);
 		return (CMD_RETURN_ERROR);
 	}
 
 	if (args_has(args, 't'))
-		return (cmd_bind_key_table(self, ctx, key));
+		return (cmd_bind_key_table(self, cmdq, key));
 
-	cmdlist = cmd_list_parse(args->argc - 1, args->argv + 1, &cause);
+	cmdlist = cmd_list_parse(args->argc - 1, args->argv + 1, NULL, 0,
+	    &cause);
 	if (cmdlist == NULL) {
-		ctx->error(ctx, "%s", cause);
+		cmdq_error(cmdq, "%s", cause);
 		free(cause);
 		return (CMD_RETURN_ERROR);
 	}
@@ -86,7 +87,7 @@ cmd_bind_key_exec(struct cmd *self, struct cmd_ctx *ctx)
 }
 
 enum cmd_retval
-cmd_bind_key_table(struct cmd *self, struct cmd_ctx *ctx, int key)
+cmd_bind_key_table(struct cmd *self, struct cmd_q *cmdq, int key)
 {
 	struct args			*args = self->args;
 	const char			*tablename;
@@ -97,25 +98,25 @@ cmd_bind_key_table(struct cmd *self, struct cmd_ctx *ctx, int key)
 
 	tablename = args_get(args, 't');
 	if ((mtab = mode_key_findtable(tablename)) == NULL) {
-		ctx->error(ctx, "unknown key table: %s", tablename);
+		cmdq_error(cmdq, "unknown key table: %s", tablename);
 		return (CMD_RETURN_ERROR);
 	}
 
 	cmd = mode_key_fromstring(mtab->cmdstr, args->argv[1]);
 	if (cmd == MODEKEY_NONE) {
-		ctx->error(ctx, "unknown command: %s", args->argv[1]);
+		cmdq_error(cmdq, "unknown command: %s", args->argv[1]);
 		return (CMD_RETURN_ERROR);
 	}
 
 	if (cmd != MODEKEYCOPY_COPYPIPE) {
 		if (args->argc != 2) {
-			ctx->error(ctx, "no argument allowed");
+			cmdq_error(cmdq, "no argument allowed");
 			return (CMD_RETURN_ERROR);
 		}
 		arg = NULL;
 	} else {
 		if (args->argc != 3) {
-			ctx->error(ctx, "no argument given");
+			cmdq_error(cmdq, "no argument given");
 			return (CMD_RETURN_ERROR);
 		}
 		arg = args->argv[2];