Implement new "i3bar_command" option for bar.

This allows you to specify an alternate path to the i3bar binary.
The userguide docu is included.

docs/userguide

@@ -796,6 +796,28 @@ bar {
 }
 ---------------------------
 
+=== i3bar command
+
+By default i3 will just pass +i3bar+ and let your shell handle the execution,
+searching your +$PATH+ for a correct version.
+If you have a different +i3bar+ somewhere or the binary is not in your +$PATH+ you can
+tell i3 what to execute.
+
+The specified command will be passed to +sh -c+, so you can use globbing and
+have to have correct quoting etc.
+
+*Syntax*:
+----------------------
+i3bar_command command
+----------------------
+
+*Example*:
+-------------------------------------------------
+bar {
+    i3bar_command /home/user/bin/i3bar
+}
+-------------------------------------------------
+
 === Statusline command
 
 i3bar can run a program and display every line of its +stdout+ output on the

include/config.h

@@ -201,6 +201,11 @@ struct Barconfig {
     /** Bar position (bottom by default). */
     enum { P_BOTTOM = 0, P_TOP = 1 } position;
 
+    /** Command that should be run to execute i3bar, give a full path if i3bar is not
+     * in your $PATH.
+     * By default just 'i3bar' is executed. */
+    char *i3bar_command;
+
     /** Command that should be run to get a statusline, for example 'i3status'.
      * Will be passed to the shell. */
     char *status_command;

src/cfgparse.l

@@ -102,6 +102,7 @@ EOL     (\r?\n)
 <BAR_POSITION>bottom            { yy_pop_state(); return TOK_BAR_BOTTOM; }
 <BAR_POSITION>top               { yy_pop_state(); return TOK_BAR_TOP; }
 <BAR>status_command             { WS_STRING; return TOK_BAR_STATUS_COMMAND; }
+<BAR>i3bar_command              { WS_STRING; return TOK_BAR_I3BAR_COMMAND; }
 <BAR>font                       { WS_STRING; return TOK_BAR_FONT; }
 <BAR>workspace_buttons          { return TOK_BAR_WORKSPACE_BUTTONS; }
 <BAR>verbose                    { return TOK_BAR_VERBOSE; }

src/cfgparse.y

@@ -705,6 +705,7 @@ void parse_file(const char *f) {
 %token                  TOK_BAR_BOTTOM              "bottom"
 %token                  TOK_BAR_TOP                 "top"
 %token                  TOK_BAR_STATUS_COMMAND      "status_command"
+%token                  TOK_BAR_I3BAR_COMMAND       "i3bar_command"
 %token                  TOK_BAR_FONT                "font (bar)"
 %token                  TOK_BAR_WORKSPACE_BUTTONS   "workspace_buttons"
 %token                  TOK_BAR_VERBOSE             "verbose"
@@ -1029,6 +1030,7 @@ barlines:
 barline:
     comment
     | bar_status_command
+    | bar_i3bar_command
     | bar_output
     | bar_tray_output
     | bar_position
@@ -1055,6 +1057,15 @@ bar_status_command:
     }
     ;
 
+bar_i3bar_command:
+    TOK_BAR_I3BAR_COMMAND STR
+    {
+        DLOG("should add i3bar_command %s\n", $2);
+        FREE(current_bar.i3bar_command);
+        current_bar.i3bar_command = $2;
+    }
+    ;
+
 bar_output:
     TOK_BAR_OUTPUT STR
     {

src/config.c

@@ -299,6 +299,7 @@ void load_configuration(xcb_connection_t *conn, const char *override_configpath,
             FREE(barconfig->tray_output);
             FREE(barconfig->socket_path);
             FREE(barconfig->status_command);
+            FREE(barconfig->i3bar_command);
             FREE(barconfig->font);
             FREE(barconfig->colors.background);
             FREE(barconfig->colors.statusline);

src/main.c

@@ -689,7 +689,8 @@ int main(int argc, char *argv[]) {
     Barconfig *barconfig;
     TAILQ_FOREACH(barconfig, &barconfigs, configs) {
         char *command = NULL;
-        sasprintf(&command, "i3bar --bar_id=%s --socket=\"%s\"",
+        sasprintf(&command, "%s --bar_id=%s --socket=\"%s\"",
+                barconfig->i3bar_command ? barconfig->i3bar_command : "i3bar",
                 barconfig->id, current_socketpath);
         LOG("Starting bar process: %s\n", command);
         start_application(command, true);