Add hooks infrastructure, basic commands (set-hook, show-hooks) and a

couple of not very useful client hooks. This will eventually let
commands be run at various points and on notifications. Joint work with
Thomas Adam.

Makefile

@@ -56,6 +56,7 @@ SRCS=	alerts.c \
 	cmd-send-keys.c \
 	cmd-set-buffer.c \
 	cmd-set-environment.c \
+	cmd-set-hook.c \
 	cmd-set-option.c \
 	cmd-show-environment.c \
 	cmd-show-messages.c \
@@ -78,6 +79,7 @@ SRCS=	alerts.c \
 	format.c \
 	grid-view.c \
 	grid.c \
+	hooks.c \
 	input-keys.c \
 	input.c \
 	job.c \

cmd-attach-session.c

@@ -108,7 +108,7 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 			TAILQ_FOREACH(c_loop, &clients, entry) {
 				if (c_loop->session != s || c == c_loop)
 					continue;
-				proc_send_s(c_loop->peer, MSG_DETACH, s->name);
+				server_client_detach(c, MSG_DETACH);
 			}
 		}
 
@@ -139,7 +139,7 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 			TAILQ_FOREACH(c_loop, &clients, entry) {
 				if (c_loop->session != s || c == c_loop)
 					continue;
-				proc_send_s(c_loop->peer, MSG_DETACH, s->name);
+				server_client_detach(c_loop, MSG_DETACH);
 			}
 		}
 
@@ -159,6 +159,7 @@ cmd_attach_session(struct cmd_q *cmdq, const char *tflag, int dflag, int rflag,
 
 		if (~c->flags & CLIENT_CONTROL)
 			proc_send(c->peer, MSG_READY, -1, NULL, 0);
+		hooks_run(c->session->hooks, "client-attached", c);
 		cmdq->client_exit = 0;
 	}
 	recalculate_sizes();

cmd-detach-client.c

@@ -72,9 +72,8 @@ cmd_detach_client_exec(struct cmd *self, struct cmd_q *cmdq)
 			return (CMD_RETURN_ERROR);
 
 		TAILQ_FOREACH(cloop, &clients, entry) {
-			if (cloop->session != s)
+			if (cloop->session == s)
-				continue;
+				server_client_detach(cloop, msgtype);
-			proc_send_s(cloop->peer, msgtype, cloop->session->name);
 		}
 		return (CMD_RETURN_STOP);
 	}
@@ -85,13 +84,12 @@ cmd_detach_client_exec(struct cmd *self, struct cmd_q *cmdq)
 
 	if (args_has(args, 'a')) {
 		TAILQ_FOREACH(cloop, &clients, entry) {
-			if (cloop->session == NULL || cloop == c)
+			if (cloop->session != NULL && cloop != c)
-				continue;
+				server_client_detach(cloop, msgtype);
-			proc_send_s(cloop->peer, msgtype, cloop->session->name);
 		}
 		return (CMD_RETURN_NORMAL);
 	}
 
-	proc_send_s(c->peer, msgtype, c->session->name);
+	server_client_detach(c, msgtype);
 	return (CMD_RETURN_STOP);
 }

cmd-set-hook.c

@@ -0,0 +1,116 @@
+/* $OpenBSD$ */
+
+/*
+ * Copyright (c) 2012 Thomas Adam <thomas@xteddy.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "tmux.h"
+
+/*
+ * Set or show global or session hooks.
+ */
+
+enum cmd_retval cmd_set_hook_exec(struct cmd *, struct cmd_q *);
+
+const struct cmd_entry cmd_set_hook_entry = {
+	"set-hook", NULL,
+	"gt:u", 1, 2,
+	"[-gu] " CMD_TARGET_SESSION_USAGE " hook-name [command]",
+	0,
+	cmd_set_hook_exec
+};
+
+const struct cmd_entry cmd_show_hooks_entry = {
+	"show-hooks", NULL,
+	"gt:", 0, 1,
+	"[-g] " CMD_TARGET_SESSION_USAGE,
+	0,
+	cmd_set_hook_exec
+};
+
+enum cmd_retval
+cmd_set_hook_exec(struct cmd *self, struct cmd_q *cmdq)
+{
+	struct args	*args = self->args;
+	struct session	*s;
+	struct cmd_list	*cmdlist;
+	struct hooks	*hooks;
+	struct hook	*hook;
+	char		*cause, *tmp;
+	const char	*name, *cmd;
+
+	if (args_has(args, 'g'))
+		hooks = global_hooks;
+	else {
+		s = cmd_find_session(cmdq, args_get(args, 't'), 0);
+		if (s == NULL)
+			return (CMD_RETURN_ERROR);
+		hooks = s->hooks;
+	}
+
+	if (self->entry == &cmd_show_hooks_entry) {
+		hook = hooks_first(hooks);
+		while (hook != NULL) {
+			tmp = cmd_list_print(hook->cmdlist);
+			cmdq_print(cmdq, "%s -> %s", hook->name, tmp);
+			free(tmp);
+
+			hook = hooks_next(hook);
+		}
+		return (CMD_RETURN_NORMAL);
+	}
+
+	name = args->argv[0];
+	if (*name == '\0') {
+		cmdq_error(cmdq, "invalid hook name");
+		return (CMD_RETURN_ERROR);
+	}
+	if (args->argc < 2)
+		cmd = NULL;
+	else
+		cmd = args->argv[1];
+
+	if (args_has(args, 'u')) {
+		if (cmd != NULL) {
+			cmdq_error(cmdq, "command passed to unset hook: %s",
+			    name);
+			return (CMD_RETURN_ERROR);
+		}
+		if ((hook = hooks_find(hooks, name)) != NULL)
+			hooks_remove(hooks, hook);
+		return (CMD_RETURN_NORMAL);
+	}
+
+	if (cmd == NULL) {
+		cmdq_error(cmdq, "no command to set hook: %s", name);
+		return (CMD_RETURN_ERROR);
+	}
+	if (cmd_string_parse(cmd, &cmdlist, NULL, 0, &cause) != 0) {
+		if (cause != NULL) {
+			cmdq_error(cmdq, "%s", cause);
+			free(cause);
+		}
+		return (CMD_RETURN_ERROR);
+	}
+	hooks_add(hooks, name, cmdlist);
+	cmd_list_free(cmdlist);
+
+	return (CMD_RETURN_NORMAL);
+}

cmd.c

@@ -96,10 +96,12 @@ extern const struct cmd_entry cmd_send_prefix_entry;
 extern const struct cmd_entry cmd_server_info_entry;
 extern const struct cmd_entry cmd_set_buffer_entry;
 extern const struct cmd_entry cmd_set_environment_entry;
+extern const struct cmd_entry cmd_set_hook_entry;
 extern const struct cmd_entry cmd_set_option_entry;
 extern const struct cmd_entry cmd_set_window_option_entry;
 extern const struct cmd_entry cmd_show_buffer_entry;
 extern const struct cmd_entry cmd_show_environment_entry;
+extern const struct cmd_entry cmd_show_hooks_entry;
 extern const struct cmd_entry cmd_show_messages_entry;
 extern const struct cmd_entry cmd_show_options_entry;
 extern const struct cmd_entry cmd_show_window_options_entry;
@@ -183,10 +185,12 @@ const struct cmd_entry *cmd_table[] = {
 	&cmd_server_info_entry,
 	&cmd_set_buffer_entry,
 	&cmd_set_environment_entry,
+	&cmd_set_hook_entry,
 	&cmd_set_option_entry,
 	&cmd_set_window_option_entry,
 	&cmd_show_buffer_entry,
 	&cmd_show_environment_entry,
+	&cmd_show_hooks_entry,
 	&cmd_show_messages_entry,
 	&cmd_show_options_entry,
 	&cmd_show_window_options_entry,

hooks.c

@@ -0,0 +1,139 @@
+/* $OpenBSD$ */
+
+/*
+ * Copyright (c) 2012 Thomas Adam <thomas@xteddy.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "tmux.h"
+
+struct hooks {
+	RB_HEAD(hooks_tree, hook) tree;
+	struct hooks	*parent;
+};
+
+static int	hooks_cmp(struct hook *, struct hook *);
+RB_PROTOTYPE(hooks_tree, hook, entry, hooks_cmp);
+RB_GENERATE(hooks_tree, hook, entry, hooks_cmp);
+
+struct hook	*hooks_find1(struct hooks *, const char *);
+
+static int
+hooks_cmp(struct hook *hook1, struct hook *hook2)
+{
+	return (strcmp(hook1->name, hook2->name));
+}
+
+struct hooks *
+hooks_create(struct hooks *parent)
+{
+	struct hooks	*hooks;
+
+	hooks = xcalloc(1, sizeof *hooks);
+	RB_INIT(&hooks->tree);
+	hooks->parent = parent;
+	return (hooks);
+}
+
+void
+hooks_free(struct hooks *hooks)
+{
+	struct hook	*hook, *hook1;
+
+	RB_FOREACH_SAFE(hook, hooks_tree, &hooks->tree, hook1)
+		hooks_remove(hooks, hook);
+	free(hooks);
+}
+
+struct hook *
+hooks_first(struct hooks *hooks)
+{
+	return (RB_MIN(hooks_tree, &hooks->tree));
+}
+
+struct hook *
+hooks_next(struct hook *hook)
+{
+	return (RB_NEXT(hooks_tree, &hooks->tree, hook));
+}
+
+void
+hooks_add(struct hooks *hooks, const char *name, struct cmd_list *cmdlist)
+{
+	struct hook	*hook;
+
+	if ((hook = hooks_find1(hooks, name)) != NULL)
+		hooks_remove(hooks, hook);
+
+	hook = xcalloc(1, sizeof *hook);
+	hook->name = xstrdup(name);
+	hook->cmdlist = cmdlist;
+	hook->cmdlist->references++;
+	RB_INSERT(hooks_tree, &hooks->tree, hook);
+}
+
+void
+hooks_remove(struct hooks *hooks, struct hook *hook)
+{
+	RB_REMOVE(hooks_tree, &hooks->tree, hook);
+	cmd_list_free(hook->cmdlist);
+	free((char *) hook->name);
+	free(hook);
+}
+
+struct hook *
+hooks_find1(struct hooks *hooks, const char *name)
+{
+	struct hook	hook;
+
+	hook.name = name;
+	return (RB_FIND(hooks_tree, &hooks->tree, &hook));
+}
+
+struct hook *
+hooks_find(struct hooks *hooks, const char *name)
+{
+	struct hook	 hook0, *hook;
+
+	hook0.name = name;
+	hook = RB_FIND(hooks_tree, &hooks->tree, &hook0);
+	while (hook == NULL) {
+		hooks = hooks->parent;
+		if (hooks == NULL)
+			break;
+		hook = RB_FIND(hooks_tree, &hooks->tree, &hook0);
+	}
+	return (hook);
+}
+
+void
+hooks_run(struct hooks *hooks, const char *name, struct client *c)
+{
+	struct hook	*hook;
+	struct cmd_q	*cmdq;
+
+	hook = hooks_find(hooks, name);
+	if (hook == NULL)
+		return;
+	log_debug("running hook %s", name);
+
+	cmdq = cmdq_new(c);
+	cmdq_run(cmdq, hook->cmdlist, NULL);
+	cmdq_free(cmdq);
+}

server-client.c

@@ -256,6 +256,19 @@ server_client_free(__unused int fd, __unused short events, void *arg)
 		free(c);
 }
 
+/* Detach a client. */
+void
+server_client_detach(struct client *c, enum msgtype msgtype)
+{
+	struct session	*s = c->session;
+
+	if (s == NULL)
+		return;
+
+	hooks_run(c->session->hooks, "client-detached", c);
+	proc_send_s(c->peer, msgtype, s->name);
+}
+
 /* Check for mouse keys. */
 key_code
 server_client_check_mouse(struct client *c)
@@ -995,6 +1008,8 @@ server_client_dispatch(struct imsg *imsg, void *arg)
 			recalculate_sizes();
 			server_redraw_client(c);
 		}
+		if (c->session != NULL)
+			hooks_run(c->session->hooks, "client-resized", c);
 		break;
 	case MSG_EXITING:
 		if (datalen != 0)

session.c

@@ -123,7 +123,9 @@ session_create(const char *name, int argc, char **argv, const char *path,
 	s->environ = environ_create();
 	if (env != NULL)
 		environ_copy(env, s->environ);
+
 	s->options = options_create(global_s_options);
+	s->hooks = hooks_create(global_hooks);
 
 	s->tio = NULL;
 	if (tio != NULL) {
@@ -189,7 +191,9 @@ session_free(__unused int fd, __unused short events, void *arg)
 
 	if (s->references == 0) {
 		environ_free(s->environ);
+
 		options_free(s->options);
+		hooks_free(s->hooks);
 
 		free(s->name);
 		free(s);

tmux.1

@@ -3193,6 +3193,52 @@ is used.
 .Fl v
 shows only the option value, not the name.
 .El
+.Sh HOOKS
+.Nm
+allows commands to run on various triggers, called
+.Em hooks .
+Each hook has a
+.Em name .
+The following hooks are available:
+.Bl -tag -width "XXXXXXXXXXXXXXXX"
+.It client-attached
+Run when a client is attached.
+.It client-detached
+Run when a client is detached
+.It client-resized
+Run when a client is resized.
+.El
+.Pp
+Hooks are managed with these commands:
+.Bl -tag -width Ds
+.It Xo Ic set-hook
+.Op Fl g
+.Op Fl t Ar target-session
+.Ar hook-name
+.Ar command
+.Xc
+Sets hook
+.Ar hook-name
+to
+.Ar command .
+If
+.Fl g
+is given,
+.Em hook-name
+is added to the global list of hooks, otherwise it is added to the session
+hooks (for
+.Ar target-session
+with
+.Fl t ) .
+Like options, session hooks inherit from the global ones.
+.It Xo Ic show-hooks
+.Op Fl g
+.Op Fl t Ar target-session
+.Xc
+Shows the global list of hooks with
+.Fl g ,
+otherwise the session hooks.
+.Ed
 .Sh MOUSE SUPPORT
 If the
 .Ic mouse

tmux.c

@@ -38,6 +38,7 @@ struct options	*global_options;	/* server options */
 struct options	*global_s_options;	/* session options */
 struct options	*global_w_options;	/* window options */
 struct environ	*global_environ;
+struct hooks	*global_hooks;
 
 struct timeval	 start_time;
 const char	*socket_path;
@@ -269,6 +270,8 @@ main(int argc, char **argv)
 			flags |= CLIENT_UTF8;
 	}
 
+	global_hooks = hooks_create(NULL);
+
 	global_environ = environ_create();
 	for (var = environ; *var != NULL; var++)
 		environ_put(global_environ, *var);

tmux.h

@@ -691,6 +691,14 @@ struct grid {
 	struct grid_line	*linedata;
 };
 
+/* Hook data structures. */
+struct hook {
+	const char      *name;
+	struct cmd_q    *cmdq;
+	struct cmd_list *cmdlist;
+	RB_ENTRY(hook)   entry;
+};
+
 /* Option data structures. */
 struct options_entry {
 	char		*name;
@@ -1011,6 +1019,7 @@ struct session {
 	struct winlink_stack lastw;
 	struct winlinks	 windows;
 
+	struct hooks	*hooks;
 	struct options	*options;
 
 #define SESSION_UNATTACHED 0x1	/* not attached to any clients */
@@ -1427,10 +1436,11 @@ struct options_table_entry {
 #define CMD_BUFFER_USAGE "[-b buffer-name]"
 
 /* tmux.c */
-extern struct options *global_options;
+extern struct hooks	*global_hooks;
-extern struct options *global_s_options;
+extern struct options	*global_options;
-extern struct options *global_w_options;
+extern struct options	*global_s_options;
-extern struct environ *global_environ;
+extern struct options	*global_w_options;
+extern struct environ	*global_environ;
 extern struct timeval	 start_time;
 extern const char	*socket_path;
 const char	*getshell(void);
@@ -1495,6 +1505,18 @@ void		 format_defaults_pane(struct format_tree *,
 void		 format_defaults_paste_buffer(struct format_tree *,
 		     struct paste_buffer *);
 
+/* hooks.c */
+struct hook;
+struct hooks	*hooks_create(struct hooks *);
+void		 hooks_free(struct hooks *);
+struct hook	*hooks_first(struct hooks *);
+struct hook	*hooks_next(struct hook *);
+void		 hooks_add(struct hooks *, const char *, struct cmd_list *);
+void		 hooks_copy(struct hooks *, struct hooks *);
+void		 hooks_remove(struct hooks *, struct hook *);
+struct hook	*hooks_find(struct hooks *, const char *);
+void		 hooks_run(struct hooks *, const char *, struct client *);
+
 /* mode-key.c */
 extern const struct mode_key_table mode_key_tables[];
 extern struct mode_key_tree mode_key_tree_vi_edit;
@@ -1782,6 +1804,7 @@ void	 server_client_create(int);
 int	 server_client_open(struct client *, char **);
 void	 server_client_unref(struct client *);
 void	 server_client_lost(struct client *);
+void	 server_client_detach(struct client *, enum msgtype);
 void	 server_client_loop(void);
 void	 server_client_push_stdout(struct client *);
 void	 server_client_push_stderr(struct client *);