player: simplify OSD message handling code

Eliminate the remains of the OSD message stack. Another simplification
comes from the fact that we do not need to care about time going
backwards (we always use a monotonic time source, and wrapping time
values are practically impossible). What this code was pretty trivial,
and by now unnecessarily roundabout.

Merge get_osd_msg() into update_osd_msg(), and add_osd_msg() into
set_osd_msg_va().

2 files changed, 60 insertions, 103 deletions

diff --git a/player/core.h b/player/core.h
index a60e13a3e7..581a5b7a42 100644
--- a/player/core.h
+++ b/player/core.h
@@ -172,7 +172,6 @@ typedef struct MPContext {
 
     struct mp_log *statusline;
     struct osd_state *osd;
-    struct mp_osd_msg *osd_msg_stack;
     char *term_osd_text;
     char *term_osd_status;
     char *term_osd_subs;
@@ -183,8 +182,11 @@ typedef struct MPContext {
     double osd_visible; // for the osd bar only
     int osd_function;
     double osd_function_visible;
+    double osd_msg_visible;
     double osd_last_update;
     bool osd_force_update;
+    char *osd_msg_text;
+    bool osd_show_pos;
     struct osd_progbar_state osd_progbar;
 
     struct playlist *playlist;
@@ -430,7 +432,7 @@ void stream_dump(struct MPContext *mpctx);
 // osd.c
 void set_osd_bar(struct MPContext *mpctx, int type,
                  double min, double max, double neutral, double val);
-void set_osd_msg(struct MPContext *mpctx, int level, int time,
+bool set_osd_msg(struct MPContext *mpctx, int level, int time,
                  const char* fmt, ...) PRINTF_ATTRIBUTE(4,5);
 void set_osd_function(struct MPContext *mpctx, int osd_function);
 void set_osd_subtitle(struct MPContext *mpctx, const char *text);
diff --git a/player/osd.c b/player/osd.c
index 757af6a4c6..8bada12bb7 100644
--- a/player/osd.c
+++ b/player/osd.c
@@ -263,105 +263,29 @@ static void print_status(struct MPContext *mpctx)
     talloc_free(line);
 }
 
-typedef struct mp_osd_msg mp_osd_msg_t;
-struct mp_osd_msg {
-    /// Message text.
-    char *msg;
-    int started;
-    /// Display duration in seconds.
-    double time;
-    // Show full OSD for duration of message instead of msg
-    // (osd_show_progression command)
-    bool show_position;
-};
-
-// time is in ms
-static mp_osd_msg_t *add_osd_msg(struct MPContext *mpctx, int level, int time)
-{
-    struct MPOpts *opts = mpctx->opts;
-    if (level > opts->osd_level)
-        return NULL;
-
-    talloc_free(mpctx->osd_msg_stack);
-    mpctx->osd_msg_stack = talloc_struct(mpctx, mp_osd_msg_t, {
-        .msg = "",
-        .time = time / 1000.0,
-    });
-    mpctx->osd_force_update = true;
-    return mpctx->osd_msg_stack;
-}
-
-static void set_osd_msg_va(struct MPContext *mpctx, int level, int time,
+static bool set_osd_msg_va(struct MPContext *mpctx, int level, int time,
                            const char *fmt, va_list ap)
 {
-    if (level == OSD_LEVEL_INVISIBLE)
-        return;
-    mp_osd_msg_t *msg = add_osd_msg(mpctx, level, time);
-    if (msg)
-        msg->msg = talloc_vasprintf(msg, fmt, ap);
+    if (level > mpctx->opts->osd_level)
+        return false;
+
+    talloc_free(mpctx->osd_msg_text);
+    mpctx->osd_msg_text = talloc_vasprintf(mpctx, fmt, ap);
+    mpctx->osd_show_pos = false;
+    mpctx->osd_msg_visible = mp_time_sec() + time / 1000.0;
+    mpctx->osd_force_update = true;
+    mpctx->sleeptime = 0;
+    return true;
 }
 
-void set_osd_msg(struct MPContext *mpctx, int level, int time,
+bool set_osd_msg(struct MPContext *mpctx, int level, int time,
                  const char *fmt, ...)
 {
     va_list ap;
     va_start(ap, fmt);
-    set_osd_msg_va(mpctx, level, time, fmt, ap);
+    bool r = set_osd_msg_va(mpctx, level, time, fmt, ap);
     va_end(ap);
-}
-
-/**
- *  \brief Get the current message from the OSD stack.
- *
- *  This function decrements the message timer and destroys the old ones.
- *  The message that should be displayed is returned (if any).
- *
- */
-
-static mp_osd_msg_t *get_osd_msg(struct MPContext *mpctx)
-{
-    double now = mp_time_sec();
-    double diff;
-
-    if (mpctx->osd_visible) {
-        double sleep = mpctx->osd_visible - now;
-        if (sleep > 0) {
-            mpctx->sleeptime = MPMIN(mpctx->sleeptime, sleep);
-        } else {
-            mpctx->osd_visible = 0;
-            mpctx->osd_progbar.type = -1; // disable
-            osd_set_progbar(mpctx->osd, &mpctx->osd_progbar);
-        }
-    }
-    if (mpctx->osd_function_visible && now >= mpctx->osd_function_visible) {
-        mpctx->osd_function_visible = 0;
-        mpctx->osd_function = 0;
-    }
-
-    if (!mpctx->osd_last_update)
-        mpctx->osd_last_update = now;
-    diff = now >= mpctx->osd_last_update ? now - mpctx->osd_last_update : 0;
-
-    mpctx->osd_last_update = now;
-
-    mp_osd_msg_t *msg = mpctx->osd_msg_stack;
-    if (msg) {
-        if (!msg->started || msg->time > diff) {
-            // display it
-            if (msg->started)
-                msg->time -= diff;
-            else
-                msg->started = 1;
-        } else {
-            // kill the message
-            talloc_free(msg);
-            msg = NULL;
-            mpctx->osd_msg_stack = NULL;
-        }
-    }
-    if (msg)
-        mpctx->sleeptime = MPMIN(mpctx->sleeptime, msg->time);
-    return msg;
+    return r;
 }
 
 // type: mp_osd_font_codepoints, ASCII, or OSD_BAR_*
@@ -498,9 +422,8 @@ static void add_seek_osd_messages(struct MPContext *mpctx)
     if (mpctx->add_osd_seek_info & OSD_SEEK_INFO_TEXT) {
         // Never in term-osd mode
         if (mpctx->video_out && mpctx->opts->term_osd != 1) {
-            mp_osd_msg_t *msg = add_osd_msg(mpctx, 1, mpctx->opts->osd_duration);
-            if (msg)
-                msg->show_position = true;
+            if (set_osd_msg(mpctx, 1, mpctx->opts->osd_duration, "%s", ""))
+                mpctx->osd_show_pos = true;
         }
     }
     if (mpctx->add_osd_seek_info & OSD_SEEK_INFO_CHAPTER_TEXT) {
@@ -526,8 +449,9 @@ void update_osd_msg(struct MPContext *mpctx)
     struct MPOpts *opts = mpctx->opts;
     struct osd_state *osd = mpctx->osd;
 
+    double now = mp_time_sec();
+
     if (!mpctx->osd_force_update) {
-        double now = mp_time_sec();
         double delay = 0.050; // update the OSD at most this often
         double diff = now - mpctx->osd_last_update;
         if (diff < delay) {
@@ -536,23 +460,54 @@ void update_osd_msg(struct MPContext *mpctx)
         }
     }
     mpctx->osd_force_update = false;
+    mpctx->osd_last_update = now;
+
+    if (mpctx->osd_visible) {
+        double sleep = mpctx->osd_visible - now;
+        if (sleep > 0) {
+            mpctx->sleeptime = MPMIN(mpctx->sleeptime, sleep);
+        } else {
+            mpctx->osd_visible = 0;
+            mpctx->osd_progbar.type = -1; // disable
+            osd_set_progbar(mpctx->osd, &mpctx->osd_progbar);
+        }
+    }
+
+    if (mpctx->osd_function_visible && now >= mpctx->osd_function_visible) {
+        mpctx->osd_function_visible = 0;
+        mpctx->osd_function = 0;
+    }
+
+    if (mpctx->osd_msg_visible) {
+        double sleep = mpctx->osd_msg_visible - now;
+        if (sleep > 0) {
+            mpctx->sleeptime = MPMIN(mpctx->sleeptime, sleep);
+        } else {
+            talloc_free(mpctx->osd_msg_text);
+            mpctx->osd_msg_text = NULL;
+            mpctx->osd_msg_visible = 0;
+            mpctx->osd_show_pos = false;
+        }
+    }
 
     add_seek_osd_messages(mpctx);
-    double pos = get_current_pos_ratio(mpctx, false);
-    update_osd_bar(mpctx, OSD_BAR_SEEK, 0, 1, MPCLAMP(pos, 0, 1));
+
+    if (mpctx->osd_progbar.type == OSD_BAR_SEEK) {
+        double pos = get_current_pos_ratio(mpctx, false);
+        update_osd_bar(mpctx, OSD_BAR_SEEK, 0, 1, MPCLAMP(pos, 0, 1));
+    }
 
     print_status(mpctx);
 
     // Look if we have a msg
-    mp_osd_msg_t *msg = get_osd_msg(mpctx);
-    if (msg && !msg->show_position) {
-        osd_set_text(osd, OSDTYPE_OSD, msg->msg);
-        term_osd_set_text(mpctx, msg->msg);
+    if (mpctx->osd_msg_text && !mpctx->osd_show_pos) {
+        osd_set_text(osd, OSDTYPE_OSD, mpctx->osd_msg_text);
+        term_osd_set_text(mpctx, mpctx->osd_msg_text);
         return;
     }
 
     int osd_level = opts->osd_level;
-    if (msg && msg->show_position)
+    if (mpctx->osd_msg_text && mpctx->osd_show_pos)
         osd_level = 3;
 
     // clear, or if OSD level demands it, show the status