action: Use a binary search for insertion

Linear searches make me cry.

1 files changed, 21 insertions, 10 deletions

diff --git a/action.c b/action.c
index 1dec134..b592ea2 100644
--- a/action.c
+++ b/action.c
@@ -30,20 +30,31 @@ static uint64_t next_seq = 0;
 
 void addaction(int x, int y, double when, enum actions what)
 {
-  int i = 0;
+  int a, b;
+  int i;
+
   if ( action_count >= MAXACT )
     return;
 
-  while ( i < action_count && actions[i].when <= when && actions[i].what )
-    i++;
+  a = 0;
+  b = action_count;
+  while (b > a) {
+    i = (a+b) >> 1;
+    if (actions[i].when <= when)
+      a = i+1;
+    else
+      b = i;
+  }
+
+  if (a < action_count)
+    memmove(&actions[a+1], &actions[a],
+	    (action_count-a)*sizeof(struct action));
 
-  memmove(&actions[i+1], &actions[i],
-	  (action_count-i)*sizeof(struct action));
-  actions[i].x = x;
-  actions[i].y = y;
-  actions[i].when = when;
-  actions[i].what = what;
-  actions[i].seq = next_seq++;
+  actions[a].x = x;
+  actions[a].y = y;
+  actions[a].when = when;
+  actions[a].what = what;
+  actions[a].seq = next_seq++;
   action_count++;
 }