Minor addition to coroutine API.

2 files changed, 8 insertions, 2 deletions

diff --git a/include/stc/algo/coroutine.h b/include/stc/algo/coroutine.h
index 2e992e55..c786eb51 100644
--- a/include/stc/algo/coroutine.h
+++ b/include/stc/algo/coroutine.h
@@ -65,6 +65,7 @@ enum {
 };
 
 #define cco_initial(co) ((co)->cco_state == 0)
+#define cco_active(co) ((co)->cco_state >= 0)
 #define cco_suspended(co) ((co)->cco_state > 0)
 #define cco_done(co) ((co)->cco_state == cco_state_done)
 
@@ -172,6 +173,11 @@ static inline void ctimer_start(ctimer* tm, long msec) {
     tm->start = clock();
 }
 
+static inline ctimer ctimer_with(long msec) {
+    ctimer tm = {msec*(CLOCKS_PER_SEC/1000), clock()};
+    return tm;
+}
+
 static inline void ctimer_restart(ctimer* tm) {
     tm->start = clock();
 }
diff --git a/misc/examples/coread.c b/misc/examples/coread.c
index ef6cd6ee..2585fb81 100644
--- a/misc/examples/coread.c
+++ b/misc/examples/coread.c
@@ -16,6 +16,7 @@ void file_read(struct file_read* g)
 {
     cco_routine(g) {
         g->fp = fopen(g->filename, "r");
+        if (!g->fp) cco_return;
         g->line = cstr_init();
 
         cco_await(!cstr_getline(&g->line, g->fp));
@@ -23,9 +24,8 @@ void file_read(struct file_read* g)
     cco_final:
         printf("finish\n");
         cstr_drop(&g->line);
-        fclose(g->fp);
+        if (g->fp) fclose(g->fp);
     }
-    return;
 }
 
 int main(void)