Add a way to mark environment variables as "hidden" so they can be used

by tmux but are not passed into the environment of new panes.

cmd-new-window.c

@@ -81,7 +81,7 @@ cmd_new_window_exec(struct cmd *self, struct cmdq_item *item)
 
 	add = args_first_value(args, 'e', &value);
 	while (add != NULL) {
-		environ_put(sc.environ, add);
+		environ_put(sc.environ, add, 0);
 		add = args_next_value(&value);
 	}
 

cmd-parse.y

@@ -99,6 +99,7 @@ static void	 cmd_parse_print_commands(struct cmd_parse_input *, u_int,
 }
 
 %token ERROR
+%token HIDDEN
 %token IF
 %token ELSE
 %token ELIF
@@ -134,6 +135,11 @@ statements	: statement '\n'
 		}
 
 statement	: /* empty */
+		{
+			$$ = xmalloc (sizeof *$$);
+			TAILQ_INIT($$);
+		}
+		| hidden_assignment
 		{
 			$$ = xmalloc (sizeof *$$);
 			TAILQ_INIT($$);
@@ -204,10 +210,21 @@ assignment	: EQUALS
 
 			if ((~flags & CMD_PARSE_PARSEONLY) &&
 			    (ps->scope == NULL || ps->scope->flag))
-				environ_put(global_environ, $1);
+				environ_put(global_environ, $1, 0);
 			free($1);
 		}
 
+hidden_assignment : HIDDEN EQUALS
+		{
+			struct cmd_parse_state	*ps = &parse_state;
+			int			 flags = ps->input->flags;
+
+			if ((~flags & CMD_PARSE_PARSEONLY) &&
+			    (ps->scope == NULL || ps->scope->flag))
+				environ_put(global_environ, $2, ENVIRON_HIDDEN);
+			free($2);
+		}
+
 if_open		: IF expanded
 		{
 			struct cmd_parse_state	*ps = &parse_state;
@@ -1079,6 +1096,10 @@ yylex(void)
 			if (*cp == '\0')
 				return (TOKEN);
 			ps->condition = 1;
+			if (strcmp(yylval.token, "%hidden") == 0) {
+				free(yylval.token);
+				return (HIDDEN);
+			}
 			if (strcmp(yylval.token, "%if") == 0) {
 				free(yylval.token);
 				return (IF);

cmd-respawn-pane.c

@@ -71,7 +71,7 @@ cmd_respawn_pane_exec(struct cmd *self, struct cmdq_item *item)
 
 	add = args_first_value(args, 'e', &value);
 	while (add != NULL) {
-		environ_put(sc.environ, add);
+		environ_put(sc.environ, add, 0);
 		add = args_next_value(&value);
 	}
 

cmd-respawn-window.c

@@ -68,7 +68,7 @@ cmd_respawn_window_exec(struct cmd *self, struct cmdq_item *item)
 
 	add = args_first_value(args, 'e', &value);
 	while (add != NULL) {
-		environ_put(sc.environ, add);
+		environ_put(sc.environ, add, 0);
 		add = args_next_value(&value);
 	}
 

cmd-set-environment.c

@@ -34,8 +34,8 @@ const struct cmd_entry cmd_set_environment_entry = {
 	.name = "set-environment",
 	.alias = "setenv",
 
-	.args = { "grt:u", 1, 2 },
-	.usage = "[-gru] " CMD_TARGET_SESSION_USAGE " name [value]",
+	.args = { "hgrt:u", 1, 2 },
+	.usage = "[-hgru] " CMD_TARGET_SESSION_USAGE " name [value]",
 
 	.target = { 't', CMD_FIND_SESSION, CMD_FIND_CANFAIL },
 
@@ -96,7 +96,10 @@ cmd_set_environment_exec(struct cmd *self, struct cmdq_item *item)
 			cmdq_error(item, "no value specified");
 			return (CMD_RETURN_ERROR);
 		}
-		environ_set(env, name, "%s", value);
+		if (args_has(args, 'h'))
+			environ_set(env, name, ENVIRON_HIDDEN, "%s", value);
+		else
+			environ_set(env, name, 0, "%s", value);
 	}
 
 	return (CMD_RETURN_NORMAL);

cmd-show-environment.c

@@ -38,8 +38,8 @@ const struct cmd_entry cmd_show_environment_entry = {
 	.name = "show-environment",
 	.alias = "showenv",
 
-	.args = { "gst:", 0, 1 },
-	.usage = "[-gs] " CMD_TARGET_SESSION_USAGE " [name]",
+	.args = { "hgst:", 0, 1 },
+	.usage = "[-hgs] " CMD_TARGET_SESSION_USAGE " [name]",
 
 	.target = { 't', CMD_FIND_SESSION, CMD_FIND_CANFAIL },
 
@@ -69,8 +69,14 @@ static void
 cmd_show_environment_print(struct cmd *self, struct cmdq_item *item,
     struct environ_entry *envent)
 {
+	struct args	*args = self->args;
 	char		*escaped;
 
+	if (!args_has(args, 'h') && (envent->flags & ENVIRON_HIDDEN))
+		return;
+	if (args_has(args, 'h') && (~envent->flags & ENVIRON_HIDDEN))
+		return;
+
 	if (!args_has(self->args, 's')) {
 		if (envent->value != NULL)
 			cmdq_print(item, "%s=%s", envent->name, envent->value);

cmd-split-window.c

@@ -142,7 +142,7 @@ cmd_split_window_exec(struct cmd *self, struct cmdq_item *item)
 
 	add = args_first_value(args, 'e', &value);
 	while (add != NULL) {
-		environ_put(sc.environ, add);
+		environ_put(sc.environ, add, 0);
 		add = args_next_value(&value);
 	}
 

environ.c

@@ -86,8 +86,10 @@ environ_copy(struct environ *srcenv, struct environ *dstenv)
 	RB_FOREACH(envent, environ, srcenv) {
 		if (envent->value == NULL)
 			environ_clear(dstenv, envent->name);
-		else
-			environ_set(dstenv, envent->name, "%s", envent->value);
+		else {
+			environ_set(dstenv, envent->name, envent->flags,
+			    "%s", envent->value);
+		}
 	}
 }
 
@@ -103,18 +105,21 @@ environ_find(struct environ *env, const char *name)
 
 /* Set an environment variable. */
 void
-environ_set(struct environ *env, const char *name, const char *fmt, ...)
+environ_set(struct environ *env, const char *name, int flags, const char *fmt,
+    ...)
 {
 	struct environ_entry	*envent;
 	va_list			 ap;
 
 	va_start(ap, fmt);
 	if ((envent = environ_find(env, name)) != NULL) {
+		envent->flags = flags;
 		free(envent->value);
 		xvasprintf(&envent->value, fmt, ap);
 	} else {
 		envent = xmalloc(sizeof *envent);
 		envent->name = xstrdup(name);
+		envent->flags = flags;
 		xvasprintf(&envent->value, fmt, ap);
 		RB_INSERT(environ, env, envent);
 	}
@@ -133,6 +138,7 @@ environ_clear(struct environ *env, const char *name)
 	} else {
 		envent = xmalloc(sizeof *envent);
 		envent->name = xstrdup(name);
+		envent->flags = 0;
 		envent->value = NULL;
 		RB_INSERT(environ, env, envent);
 	}
@@ -140,7 +146,7 @@ environ_clear(struct environ *env, const char *name)
 
 /* Set an environment variable from a NAME=VALUE string. */
 void
-environ_put(struct environ *env, const char *var)
+environ_put(struct environ *env, const char *var, int flags)
 {
 	char	*name, *value;
 
@@ -152,7 +158,7 @@ environ_put(struct environ *env, const char *var)
 	name = xstrdup(var);
 	name[strcspn(name, "=")] = '\0';
 
-	environ_set(env, name, "%s", value);
+	environ_set(env, name, flags, "%s", value);
 	free(name);
 }
 
@@ -170,7 +176,7 @@ environ_unset(struct environ *env, const char *name)
 	free(envent);
 }
 
-/* Copy variables from a destination into a source * environment. */
+/* Copy variables from a destination into a source environment. */
 void
 environ_update(struct options *oo, struct environ *src, struct environ *dst)
 {
@@ -188,7 +194,7 @@ environ_update(struct options *oo, struct environ *src, struct environ *dst)
 		if ((envent = environ_find(src, ov->string)) == NULL)
 			environ_clear(dst, ov->string);
 		else
-			environ_set(dst, envent->name, "%s", envent->value);
+			environ_set(dst, envent->name, 0, "%s", envent->value);
 		a = options_array_next(a);
 	}
 }
@@ -201,7 +207,9 @@ environ_push(struct environ *env)
 
 	environ = xcalloc(1, sizeof *environ);
 	RB_FOREACH(envent, environ, env) {
-		if (envent->value != NULL && *envent->name != '\0')
+		if (envent->value != NULL &&
+		    *envent->name != '\0' &&
+		    (~envent->flags & ENVIRON_HIDDEN))
 			setenv(envent->name, envent->value, 1);
 	}
 }
@@ -243,14 +251,15 @@ environ_for_session(struct session *s, int no_TERM)
 
 	if (!no_TERM) {
 		value = options_get_string(global_options, "default-terminal");
-		environ_set(env, "TERM", "%s", value);
+		environ_set(env, "TERM", 0, "%s", value);
 	}
 
 	if (s != NULL)
 		idx = s->id;
 	else
 		idx = -1;
-	environ_set(env, "TMUX", "%s,%ld,%d", socket_path, (long)getpid(), idx);
+	environ_set(env, "TMUX", 0, "%s,%ld,%d", socket_path, (long)getpid(),
+	    idx);
 
 	return (env);
 }

server-client.c

@@ -520,6 +520,7 @@ server_client_check_mouse(struct client *c, struct key_event *event)
 			memcpy(&c->click_event, m, sizeof c->click_event);
 			c->click_button = m->b;
 
+			log_debug("click timer started");
 			tv.tv_sec = KEYC_CLICK_TIMEOUT / 1000;
 			tv.tv_usec = (KEYC_CLICK_TIMEOUT % 1000) * 1000L;
 			evtimer_del(&c->click_timer);
@@ -2020,7 +2021,7 @@ server_client_dispatch_identify(struct client *c, struct imsg *imsg)
 		if (datalen == 0 || data[datalen - 1] != '\0')
 			fatalx("bad MSG_IDENTIFY_ENVIRON string");
 		if (strchr(data, '=') != NULL)
-			environ_put(c->environ, data);
+			environ_put(c->environ, data, 0);
 		log_debug("client %p IDENTIFY_ENVIRON %s", c, data);
 		break;
 	case MSG_IDENTIFY_CLIENTPID:

spawn.c

@@ -303,7 +303,7 @@ spawn_pane(struct spawn_context *sc, char **cause)
 	child = environ_for_session(s, 0);
 	if (sc->environ != NULL)
 		environ_copy(sc->environ, child);
-	environ_set(child, "TMUX_PANE", "%%%u", new_wp->id);
+	environ_set(child, "TMUX_PANE", 0, "%%%u", new_wp->id);
 
 	/*
 	 * Then the PATH environment variable. The session one is replaced from
@@ -313,10 +313,10 @@ spawn_pane(struct spawn_context *sc, char **cause)
 	if (c != NULL && c->session == NULL) { /* only unattached clients */
 		ee = environ_find(c->environ, "PATH");
 		if (ee != NULL)
-			environ_set(child, "PATH", "%s", ee->value);
+			environ_set(child, "PATH", 0, "%s", ee->value);
 	}
 	if (environ_find(child, "PATH") == NULL)
-		environ_set(child, "%s", _PATH_DEFPATH);
+		environ_set(child, "PATH", 0, "%s", _PATH_DEFPATH);
 
 	/* Then the shell. If respawning, use the old one. */
 	if (~sc->flags & SPAWN_RESPAWN) {
@@ -326,7 +326,7 @@ spawn_pane(struct spawn_context *sc, char **cause)
 		free(new_wp->shell);
 		new_wp->shell = xstrdup(tmp);
 	}
-	environ_set(child, "SHELL", "%s", new_wp->shell);
+	environ_set(child, "SHELL", 0, "%s", new_wp->shell);
 
 	/* Log the arguments we are going to use. */
 	log_debug("%s: shell=%s", __func__, new_wp->shell);

tmux.1

@@ -565,6 +565,18 @@ Environment variables may be set by using the syntax
 for example
 .Ql HOME=/home/user .
 Variables set during parsing are added to the global environment.
+A hidden variable may be set with
+.Ql %hidden ,
+for example:
+.Bd -literal -offset indent
+%hidden MYVAR=42
+.Ed
+.Pp
+Hidden variables are not passed to the environment of processes created
+by tmux.
+See the
+.Sx GLOBAL AND SESSION ENVIRONMENT
+section.
 .Pp
 Commands may be parsed conditionally by surrounding them with
 .Ql %if ,
@@ -4711,10 +4723,16 @@ from inside, and the
 variable with the correct terminal setting of
 .Ql screen .
 .Pp
+Variables in both session and global environments may be marked as hidden.
+Hidden variables are not passed into the environment of new processes and
+instead can only be used by tmux itself (for example in formats, see the
+.Sx FORMATS
+section).
+.Pp
 Commands to alter and view the environment are:
 .Bl -tag -width Ds
 .It Xo Ic set-environment
-.Op Fl gru
+.Op Fl hgru
 .Op Fl t Ar target-session
 .Ar name Op Ar value
 .Xc
@@ -4731,8 +4749,10 @@ flag unsets a variable.
 .Fl r
 indicates the variable is to be removed from the environment before starting a
 new process.
+.Fl h
+marks the variable as hidden.
 .It Xo Ic show-environment
-.Op Fl gs
+.Op Fl hgs
 .Op Fl t Ar target-session
 .Op Ar variable
 .Xc
@@ -4749,6 +4769,8 @@ Variables removed from the environment are prefixed with
 If
 .Fl s
 is used, the output is formatted as a set of Bourne shell commands.
+.Fl h
+shows hidden variables (omitted by default).
 .El
 .Sh STATUS LINE
 .Nm

tmux.c

@@ -332,9 +332,9 @@ main(int argc, char **argv)
 
 	global_environ = environ_create();
 	for (var = environ; *var != NULL; var++)
-		environ_put(global_environ, *var);
+		environ_put(global_environ, *var, 0);
 	if ((cwd = find_cwd()) != NULL)
-		environ_set(global_environ, "PWD", "%s", cwd);
+		environ_set(global_environ, "PWD", 0, "%s", cwd);
 
 	global_options = options_create(NULL);
 	global_s_options = options_create(NULL);

tmux.h

@@ -1048,6 +1048,9 @@ struct environ_entry {
 	char		*name;
 	char		*value;
 
+	int		 flags;
+#define ENVIRON_HIDDEN 0x1
+
 	RB_ENTRY(environ_entry) entry;
 };
 
@@ -1957,10 +1960,10 @@ struct environ_entry *environ_first(struct environ *);
 struct environ_entry *environ_next(struct environ_entry *);
 void	environ_copy(struct environ *, struct environ *);
 struct environ_entry *environ_find(struct environ *, const char *);
-void printflike(3, 4) environ_set(struct environ *, const char *, const char *,
-	    ...);
+void printflike(4, 5) environ_set(struct environ *, const char *, int,
+	    const char *, ...);
 void	environ_clear(struct environ *, const char *);
-void	environ_put(struct environ *, const char *);
+void	environ_put(struct environ *, const char *, int);
 void	environ_unset(struct environ *, const char *);
 void	environ_update(struct options *, struct environ *, struct environ *);
 void	environ_push(struct environ *);