gui: Switch to the standard paraslash scheduler.
authorAndre Noll <maan@systemlinux.org>
Sat, 4 Jan 2014 06:04:26 +0000 (06:04 +0000)
committerAndre Noll <maan@systemlinux.org>
Sun, 4 May 2014 13:48:54 +0000 (15:48 +0200)
Due to the preparations performed in previous patches, this is a
rather simple change. Note we don't need to define a struct signal_task
since this structure is already defined in signal.h.

configure.ac
gui.c

index 30bce8e..e423d85 100644 (file)
@@ -1102,6 +1102,7 @@ if test "$have_curses" = "yes"; then
                gui
                gui_theme
                time
+               sched
                version
                ggo
        "
diff --git a/gui.c b/gui.c
index b239714..182545c 100644 (file)
--- a/gui.c
+++ b/gui.c
@@ -30,8 +30,6 @@
 INIT_GUI_ERRLISTS;
 static char *stat_content[NUM_STAT_ITEMS];
 
-static int signal_pipe;
-
 static struct gui_window {
        WINDOW *win;
 } top, bot, sb, in, sep;
@@ -122,6 +120,18 @@ GUI_COMMANDS
 
 static struct gui_command command_list[] = {GUI_COMMANDS {.name = NULL}};
 
+struct input_task {
+       struct task task;
+};
+
+struct status_task {
+       struct task task;
+};
+
+struct cmd_task {
+       struct task task;
+};
+
 static int find_cmd_byname(char *name)
 {
        int i;
@@ -469,16 +479,6 @@ static __printf_2_3 void curses_log(int ll, const char *fmt,...)
 }
 __printf_2_3 void (*para_log)(int, const char*, ...) = curses_log;
 
-static void setup_signal_handling(void)
-{
-       signal_pipe = para_signal_init();
-       para_install_sighandler(SIGINT);
-       para_install_sighandler(SIGTERM);
-       para_install_sighandler(SIGCHLD);
-       para_install_sighandler(SIGWINCH);
-       para_install_sighandler(SIGUSR1);
-}
-
 static void shutdown_curses(void)
 {
        def_prog_mode();
@@ -574,21 +574,14 @@ static void clear_all_items(void)
 
 static struct timeval next_exec;
 
-static void status_pre_select(fd_set *rfds, int *max_fileno, struct timeval *tv)
+static void status_pre_select(struct sched *s, __a_unused struct task *t)
 {
-       struct timeval atm, diff;
-
        if (stat_pipe >= 0)
-               return para_fd_set(stat_pipe, rfds, max_fileno);
-       gettimeofday(&atm, NULL);
-       if (tv_diff(&next_exec, &atm, &diff) > 0) {
-               *tv = diff;
-               return;
-       }
-       tv->tv_sec = tv->tv_usec = 0; /* min delay */
+               return para_fd_set(stat_pipe, &s->rfds, &s->max_fileno);
+       sched_request_barrier_or_min_delay(&next_exec, s);
 }
 
-static void status_post_select(fd_set *rfds)
+static int status_post_select(struct sched *s, __a_unused struct task *t)
 {
        static char *buf;
        static int bufsize, loaded;
@@ -597,36 +590,34 @@ static void status_post_select(fd_set *rfds)
        int ret, ret2;
 
        if (stat_pipe < 0) {
-               struct timeval atm;
                int fds[3] = {0, 1, 0};
                /* Avoid busy loop */
-               gettimeofday(&atm, NULL);
-               if (tv_diff(&next_exec, &atm, NULL) > 0)
-                       return;
-               next_exec.tv_sec = atm.tv_sec + 2;
+               if (tv_diff(&next_exec, now, NULL) > 0)
+                       return 0;
+               next_exec.tv_sec = now->tv_sec + 2;
                ret = para_exec_cmdline_pid(&pid, conf.stat_cmd_arg, fds);
                if (ret < 0)
-                       return;
+                       return 0;
                ret = mark_fd_nonblocking(fds[1]);
                if (ret < 0) {
                        close(fds[1]);
-                       return;
+                       return 0;
                }
                stat_pipe = fds[1];
-               return;
+               return 0;
        }
 
        if (loaded >= bufsize) {
                if (bufsize > 1000 * 1000) {
                        loaded = 0;
-                       return;
+                       return 0;
                }
                bufsize += bufsize + 1000;
                buf = para_realloc(buf, bufsize);
        }
        assert(loaded < bufsize);
        ret = read_nonblock(stat_pipe, buf + loaded, bufsize - loaded,
-               rfds, &sz);
+               &s->rfds, &sz);
        loaded += sz;
        ret2 = for_each_stat_item(buf, loaded, update_item);
        if (ret < 0 || ret2 < 0) {
@@ -639,12 +630,13 @@ static void status_post_select(fd_set *rfds)
                stat_content[SI_BASENAME] =
                        para_strdup("stat command terminated!?");
                print_all_items();
-               return;
+               return 0;
        }
        sz = ret2; /* what is left */
        if (sz > 0 && sz < loaded)
                memmove(buf, buf + loaded - sz, sz);
        loaded = sz;
+       return 0;
 }
 
 /*
@@ -885,36 +877,38 @@ static void reread_conf(void)
 /*
  * React to various signal-related events
  */
-static void signal_post_select(fd_set *rfds)
+static int signal_post_select(struct sched *s, __a_unused struct task *t)
 {
-       int ret = para_next_signal(rfds);
+       int ret = para_next_signal(&s->rfds);
+
        if (ret <= 0)
-               return;
+               return 0;
        switch (ret) {
        case SIGTERM:
                die(EXIT_FAILURE, "only the good die young (caught SIGTERM)\n");
-               return;
+               return 1;
        case SIGWINCH:
                if (curses_active()) {
                        shutdown_curses();
                        init_curses();
                        redraw_bot_win();
                }
-               return;
+               return 1;
        case SIGINT:
                PARA_WARNING_LOG("caught SIGINT, reset\n");
                /* Nothing to do. SIGINT killed our child which gets noticed
                 * by do_select and resets everything.
                 */
-               return;
+               return 1;
        case SIGUSR1:
                PARA_NOTICE_LOG("got SIGUSR1, rereading configuration\n");
                reread_conf();
-               return;
+               return 1;
        case SIGCHLD:
                check_sigchld();
-               return;
+               return 1;
        }
+       return 1;
 }
 
 #define COMMAND_BUF_SIZE 32768
@@ -928,19 +922,19 @@ static enum cmd_status cmd_status(void)
        return CMDS_IDLE;
 }
 
-static void command_pre_select(fd_set *rfds, int *max_fileno)
+static void command_pre_select(struct sched *s, __a_unused struct task *t)
 {
        enum cmd_status cmds = cmd_status();
 
        if (cmds != CMDS_DCMD)
                return;
        if (command_fds[0] >= 0)
-               para_fd_set(command_fds[0], rfds, max_fileno);
+               para_fd_set(command_fds[0], &s->rfds, &s->max_fileno);
        if (command_fds[1] >= 0)
-               para_fd_set(command_fds[1], rfds, max_fileno);
+               para_fd_set(command_fds[1], &s->rfds, &s->max_fileno);
 }
 
-static void command_post_select(fd_set *rfds)
+static int command_post_select(struct sched *s, __a_unused struct task *t)
 {
        int i, ret;
        static char command_buf[2][COMMAND_BUF_SIZE];
@@ -949,14 +943,14 @@ static void command_post_select(fd_set *rfds)
        enum cmd_status cmds = cmd_status();
 
        if (cmds != CMDS_DCMD)
-               return;
+               return 0;
        for (i = 0; i < 2; i++) {
                size_t sz;
                if (command_fds[i] < 0)
                        continue;
                ret = read_nonblock(command_fds[i],
                        command_buf[i] + cbo[i],
-                       COMMAND_BUF_SIZE - 1 - cbo[i], rfds, &sz);
+                       COMMAND_BUF_SIZE - 1 - cbo[i], &s->rfds, &sz);
                cbo[i] += sz;
                sz = cbo[i];
                cbo[i] = for_each_line(flags[i], command_buf[i], cbo[i],
@@ -974,7 +968,7 @@ static void command_post_select(fd_set *rfds)
                        flags[i] = 0;
                        cbo[i] = 0;
                        if (command_fds[!i] < 0) /* both fds closed */
-                               return;
+                               return 1;
                }
                if (cbo[i] == COMMAND_BUF_SIZE - 1) {
                        PARA_NOTICE_LOG("discarding overlong line");
@@ -982,14 +976,15 @@ static void command_post_select(fd_set *rfds)
                        flags[i] = FELF_DISCARD_FIRST;
                }
        }
+       return 0;
 }
 
-static void input_pre_select(fd_set *rfds, int *max_fileno)
+static void input_pre_select(struct sched *s, __a_unused struct task *t)
 {
        enum cmd_status cmds = cmd_status();
 
        if (cmds != CMDS_XCMD)
-               para_fd_set(STDIN_FILENO, rfds, max_fileno);
+               para_fd_set(STDIN_FILENO, &s->rfds, &s->max_fileno);
 }
 
 /* read from command pipe and print data to bot window */
@@ -1087,57 +1082,29 @@ static void handle_command(int c)
                km_keyname(c));
 }
 
-static void input_post_select(void)
+static int input_post_select(__a_unused struct sched *s, __a_unused struct task *t)
 {
        int ret;
        enum cmd_status cmds = cmd_status();
 
        if (cmds == CMDS_XCMD)
-               return;
+               return 0;
        ret = wgetch(top.win);
        if (ret == ERR || ret == KEY_RESIZE)
-               return;
-       if (cmds == CMDS_IDLE)
-               return handle_command(ret);
+               return 0;
+       if (cmds == CMDS_IDLE) {
+               handle_command(ret);
+               return 0;
+       }
        if (cmd_pid != 0)
                kill(cmd_pid, SIGTERM);
+       return 0;
 }
 
-static void signal_pre_select(fd_set *rfds, int *max_fileno)
+static void signal_pre_select(struct sched *s, struct task *t)
 {
-       para_fd_set(signal_pipe, rfds, max_fileno);
-}
-
-/*
- * This is the core select loop. It checks the following fds:
- *
- * - signal pipe
- * - stdin
- * - stdout/stderr of display or internal commands
- */
-__noreturn static void do_select(void)
-{
-       fd_set rfds;
-       int ret, max_fileno;
-       struct timeval tv;
-
-repeat:
-       tv.tv_sec = conf.timeout_arg  / 1000;
-       tv.tv_usec = (conf.timeout_arg % 1000) * 1000;
-       FD_ZERO(&rfds);
-       max_fileno = 0;
-       status_pre_select(&rfds, &max_fileno, &tv);
-       signal_pre_select(&rfds, &max_fileno);
-       command_pre_select(&rfds, &max_fileno);
-       input_pre_select(&rfds, &max_fileno);
-       ret = para_select(max_fileno + 1, &rfds, NULL, &tv);
-       if (ret <= 0)
-               goto repeat; /* skip fd checks */
-       signal_post_select(&rfds);
-       command_post_select(&rfds);
-       status_post_select(&rfds);
-       input_post_select();
-       goto repeat;
+       struct signal_task *st = container_of(t, struct signal_task, task);
+       para_fd_set(st->fd, &s->rfds, &s->max_fileno);
 }
 
 static void print_scroll_msg(void)
@@ -1408,6 +1375,56 @@ __noreturn static void print_help_and_die(void)
        exit(0);
 }
 
+static int setup_tasks_and_schedule(void)
+{
+       struct sched sched = {
+               .default_timeout = {
+                       .tv_sec = conf.timeout_arg  / 1000,
+                       .tv_usec = (conf.timeout_arg % 1000) * 1000,
+               },
+       };
+       struct cmd_task cmd_task = {
+               .task = {
+                       .status = "cmd",
+                       .pre_select = command_pre_select,
+                       .post_select = command_post_select,
+               },
+       };
+       struct status_task status_task = {
+               .task = {
+                       .status = "status",
+                       .pre_select = status_pre_select,
+                       .post_select = status_post_select,
+               },
+       };
+       struct input_task input_task = {
+               .task = {
+                       .status = "input",
+                       .pre_select = input_pre_select,
+                       .post_select = input_post_select,
+               },
+       };
+       struct signal_task signal_task = {
+               .task = {
+                       .status = "signal",
+                       .pre_select = signal_pre_select,
+                       .post_select = signal_post_select,
+               },
+       };
+       signal_task.fd = para_signal_init();
+       para_install_sighandler(SIGINT);
+       para_install_sighandler(SIGTERM);
+       para_install_sighandler(SIGCHLD);
+       para_install_sighandler(SIGWINCH);
+       para_install_sighandler(SIGUSR1);
+
+       register_task(&sched, &cmd_task.task);
+       register_task(&sched, &status_task.task);
+       register_task(&sched, &input_task.task);
+       register_task(&sched, &signal_task.task);
+       return schedule(&sched);
+}
+
 int main(int argc, char *argv[])
 {
        gui_cmdline_parser(argc, argv, &conf); /* exits on errors */
@@ -1416,10 +1433,9 @@ int main(int argc, char *argv[])
        if (conf.help_given || conf.detailed_help_given)
                print_help_and_die();
        parse_config_file_or_die(false /* override */);
-       setup_signal_handling();
        bot_win_rb = ringbuffer_new(RINGBUFFER_SIZE);
        setlocale(LC_CTYPE, "");
        initscr(); /* needed only once, always successful */
        init_curses();
-       do_select();
+       return setup_tasks_and_schedule() < 0? EXIT_FAILURE : EXIT_SUCCESS;
 }