Safer state machine in coroutine.h (internal).

Removed c_forwhile() macro. Redundant, use c_forfilter().
Removed find and eq in cspan (use general c_find_if() instead for search).

1 files changed, 7 insertions, 2 deletions

diff --git a/include/stc/algo/coroutine.h b/include/stc/algo/coroutine.h
index 1c849d49..1dd82720 100644
--- a/include/stc/algo/coroutine.h
+++ b/include/stc/algo/coroutine.h
@@ -68,12 +68,11 @@ enum {
 #define cco_begin(ctx) \
     int *_state = &(ctx)->cco_state; \
     switch (*_state) { \
-        case cco_state_done: \
         case 0:
 
 #define cco_end(retval) \
         *_state = cco_state_done; break; \
-        default: goto _cco_final_; /*  never happens */ \
+        default: assert(0); goto _cco_final_; \
     } \
     return retval
 
@@ -109,4 +108,10 @@ enum {
         if (*_state > 0) *_state = cco_state_final; \
     } while (0)
 
+#define cco_reset(ctx) \
+    do { \
+        int* _state = &(ctx)->cco_state; \
+        if (*_state == cco_state_final) *_state = 0; \
+    } while (0)
+
 #endif