fixes

1 files changed, 21 insertions, 10 deletions

diff --git a/coroutine.c b/coroutine.c
index 9e0920d..6219883 100644
--- a/coroutine.c
+++ b/coroutine.c
@@ -109,20 +109,26 @@ void coroutine_main(void) {
 	for (coroutine_running = 1;; coroutine_running = (coroutine_running%COROUTINE_NUM)+1) {
 		if (coroutine_running == 1)
 			ran = false;
-		if (coroutine_table[coroutine_running-1].state == CR_RUNNABLE) {
-			printf("running %zu...\n", coroutine_running);
+		struct coroutine *cr = &coroutine_table[coroutine_running-1];
+		if (cr->state == CR_RUNNABLE) {
 			ran = true;
-			coroutine_table[coroutine_running-1].state = CR_RUNNING;
+			cr->state = CR_RUNNING;
 			if (!setjmp(coroutine_main_env)) { /* point=b */
-				longjmp(coroutine_table[coroutine_running-1].env, 1); /* jump to point=c */
+				longjmp(cr->env, 1); /* jump to point=c */
 				assert(false); /* should cr_exit() instead of returning */
 			}
-			if (coroutine_table[coroutine_running-1].state == CR_NONE) {
-				free(coroutine_table[coroutine_running-1].stack);
+			if (cr->state == CR_NONE) {
+#if DEBUG
+				size_t stack_used = cr->stack_size;
+				while (stack_used > 0 && ((uint8_t*)cr->stack)[STACK_GROWS_DOWNWARD ? cr->stack_size - stack_used : stack_used - 1] == 0)
+					stack_used--;
+				printf("info: coroutine %zu exited having used %zu B stack space\n", coroutine_running, stack_used);
+#endif
+				free(cr->stack);
 				coroutine_table[coroutine_running-1] = (struct coroutine){0};
 			}
 		}
-		if (coroutine_running == COROUTINE_NUM+1 && !ran) {
+		if (coroutine_running == COROUTINE_NUM && !ran) {
 			fprintf(stderr, "error: no runnable coroutines\n");
 			return;
 		}
@@ -136,17 +142,22 @@ bool cr_begin(void) {
 		longjmp(coroutine_add_env, 1); /* jump to point=a */
 }
 
-static inline void _cr_transition(enum coroutine_state state) {
+static inline __attribute__ ((no_split_stack)) void _cr_transition(enum coroutine_state state) {
 	assert(coroutine_table[coroutine_running-1].state == CR_RUNNING);
 	coroutine_table[coroutine_running-1].state = state;
-	if (state == CR_NONE || !setjmp(coroutine_table[coroutine_running-1].env))  /* point=c2 */
+	if (!setjmp(coroutine_table[coroutine_running-1].env))  /* point=c2 */
 		longjmp(coroutine_main_env, 1); /* jump to point=b */
 }
 
-void cr_exit(void)            { _cr_transition(CR_NONE); }
 void cr_yield(void)           { _cr_transition(CR_RUNNABLE); }
 void cr_pause_and_yield(void) { _cr_transition(CR_PAUSED); }
 
+void cr_exit(void) {
+	assert(coroutine_table[coroutine_running-1].state == CR_RUNNING);
+	coroutine_table[coroutine_running-1].state = CR_NONE;
+	longjmp(coroutine_main_env, 1); /* jump to point=b */
+}
+
 void cr_unpause(cid_t cid) {
 	assert(coroutine_table[cid-1].state == CR_PAUSED);
 	coroutine_table[cid-1].state = CR_RUNNABLE;