commands: add pt_clear command to clear playlist

This deletes all playlist elements, except the currently active
playlist entry.

NOTE: this doesn't remove parent nodes in the case when we really have
a play tree (as opposed to a play list). Apparently this doesn't cause
any harm.

3 files changed, 29 insertions, 0 deletions

diff --git a/command.c b/command.c
index 8c5d02e81d..fab9ccabd7 100644
--- a/command.c
+++ b/command.c
@@ -21,6 +21,7 @@
 #include <unistd.h>
 #include <string.h>
 #include <stdbool.h>
+#include <assert.h>
 
 #include "config.h"
 #include "talloc.h"
@@ -2787,6 +2788,28 @@ static void remove_subtitle_range(MPContext *mpctx, int start, int count)
     }
 }
 
+static void do_clear_pt(struct play_tree *node, struct play_tree *exclude)
+{
+    while (node) {
+        do_clear_pt(node->child, exclude);
+        struct play_tree *next = node->next;
+        // do not delete root node, or nodes that could lead to "exclude" node
+        if (node->parent && !node->child && node != exclude)
+            play_tree_remove(node, 1, 1);
+        node = next;
+    }
+}
+
+static void clear_play_tree(MPContext *mpctx)
+{
+    struct play_tree *exclude = NULL;
+    if (mpctx->playtree_iter) {
+        assert(mpctx->playtree == mpctx->playtree_iter->root);
+        exclude = mpctx->playtree_iter->tree;
+    }
+    do_clear_pt(mpctx->playtree, exclude);
+}
+
 void run_command(MPContext *mpctx, mp_cmd_t *cmd)
 {
     struct MPOpts *opts = &mpctx->opts;
@@ -3116,6 +3139,10 @@ void run_command(MPContext *mpctx, mp_cmd_t *cmd)
         break;
     }
 
+    case MP_CMD_PLAY_TREE_CLEAR:
+        clear_play_tree(mpctx);
+        break;
+
     case MP_CMD_STOP:
         // Go back to the starting point.
         while (play_tree_iter_up_step(mpctx->playtree_iter, 0, 1) !=
diff --git a/input/input.c b/input/input.c
index a880a583d8..c6d5470bb5 100644
--- a/input/input.c
+++ b/input/input.c
@@ -184,6 +184,7 @@ static const mp_cmd_t mp_cmds[] = {
   { MP_CMD_SWITCH_VSYNC, "switch_vsync", 0, { {MP_CMD_ARG_INT} } },
   { MP_CMD_LOADFILE, "loadfile", 1, { {MP_CMD_ARG_STRING}, {MP_CMD_ARG_INT} } },
   { MP_CMD_LOADLIST, "loadlist", 1, { {MP_CMD_ARG_STRING}, {MP_CMD_ARG_INT} } },
+  { MP_CMD_PLAY_TREE_CLEAR, "pt_clear", 0 },
   { MP_CMD_RUN, "run", 1, { {MP_CMD_ARG_STRING} } },
   { MP_CMD_CAPTURING, "capturing", 0 },
   { MP_CMD_VF_CHANGE_RECTANGLE, "change_rectangle", 2, { {MP_CMD_ARG_INT}, {MP_CMD_ARG_INT} } },
diff --git a/input/input.h b/input/input.h
index 99a69c7355..084e2dd3e7 100644
--- a/input/input.h
+++ b/input/input.h
@@ -50,6 +50,7 @@ enum mp_command_type {
     MP_CMD_MUTE,
     MP_CMD_LOADFILE,
     MP_CMD_LOADLIST,
+    MP_CMD_PLAY_TREE_CLEAR,
     MP_CMD_VF_CHANGE_RECTANGLE,
     MP_CMD_GAMMA,
     MP_CMD_SUB_VISIBILITY,