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.

11 files changed, 364 insertions, 13 deletions

diff --git a/Makefile b/Makefile
index 10c6a783..a60f1f19 100644
--- a/Makefile
+++ b/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 \
diff --git a/cmd-attach-session.c b/cmd-attach-session.c
index 5bde0d80..45b05b09 100644
--- a/cmd-attach-session.c
+++ b/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();
diff --git a/cmd-detach-client.c b/cmd-detach-client.c
index f7369df0..d8128eae 100644
--- a/cmd-detach-client.c
+++ b/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)
-				continue;
-			proc_send_s(cloop->peer, msgtype, cloop->session->name);
+			if (cloop->session == s)
+				server_client_detach(cloop, msgtype);
 		}
 		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)
-				continue;
-			proc_send_s(cloop->peer, msgtype, cloop->session->name);
+			if (cloop->session != NULL && cloop != c)
+				server_client_detach(cloop, msgtype);
 		}
 		return (CMD_RETURN_NORMAL);
 	}
 
-	proc_send_s(c->peer, msgtype, c->session->name);
+	server_client_detach(c, msgtype);
 	return (CMD_RETURN_STOP);
 }
diff --git a/cmd-set-hook.c b/cmd-set-hook.c
new file mode 100644
index 00000000..f35e7a0a
--- /dev/null
+++ b/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);
+}
diff --git a/cmd.c b/cmd.c
index 824d9caf..a950a49a 100644
--- a/cmd.c
+++ b/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,
diff --git a/hooks.c b/hooks.c
new file mode 100644
index 00000000..95d6b9d8
--- /dev/null
+++ b/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);
+}
diff --git a/server-client.c b/server-client.c
index d2abd356..c948e980 100644
--- a/server-client.c
+++ b/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)
diff --git a/session.c b/session.c
index c5721c9a..b3ae2b42 100644
--- a/session.c
+++ b/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);
diff --git a/tmux.1 b/tmux.1
index 7d45688c..6971100e 100644
--- a/tmux.1
+++ b/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
diff --git a/tmux.c b/tmux.c
index 68f0092d..fe5e54a5 100644
--- a/tmux.c
+++ b/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);
diff --git a/tmux.h b/tmux.h
index a1e16955..fa589f57 100644
--- a/tmux.h
+++ b/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 options *global_s_options;
-extern struct options *global_w_options;
-extern struct environ *global_environ;
+extern struct hooks	*global_hooks;
+extern struct options	*global_options;
+extern struct options	*global_s_options;
+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 *);