Addition to coroutine.h. Allow dynamic allocation of context.

3 files changed, 29 insertions, 15 deletions

diff --git a/include/stc/algo/coroutine.h b/include/stc/algo/coroutine.h
index 4ba39e63..7ea53a0c 100644
--- a/include/stc/algo/coroutine.h
+++ b/include/stc/algo/coroutine.h
@@ -61,14 +61,15 @@ int main(void) {
 #include <stc/ccommon.h>
 
 #define cco_begin(c) \
-     int* _state = &(c)->cco_state; \
-     switch (*_state) { \
+    int *_state = &(c)->cco_state, _nodyn; \
+    switch (*_state) { \
         case 0:
 
 #define cco_end() \
         *_state = 0; break; \
         default: assert(!"missing cco_final: or illegal state"); \
-    } *_state *= -1
+    } \
+    *_state *= -1; (void)_nodyn
 
 #define cco_yield(retval) \
     do { \
@@ -84,7 +85,22 @@ int main(void) {
     } while (0)
 
 #define cco_final case -1
-#define cco_alive(c) ((c)->cco_state > 0)
-#define cco_stop(c) ((c)->cco_state = cco_alive(c) ? -1 : -2, c)
+#define cco_alive(c) ((c) && (c)->cco_state > 0)
+#define cco_stop(c) ((c)->cco_state = (c)->cco_state ? -1 : -2, c)
+
+// ---------------------------------------------------------------
+
+#define cco_begin_dyn(cp) \
+    if (!*(cp)) *(cp) = malloc(sizeof **(cp)), (*(cp))->cco_state = 0; \
+    int* _state = &(*(cp))->cco_state, _dyn; \
+    switch (*_state) { \
+        case 0:
+
+#define cco_end_dyn(cp) \
+        *_state = 0; break; \
+        default: assert(!"missing cco_final: or illegal state"); \
+    } \
+    *_state *= -1; (void)_dyn; \
+    free(*(cp)); *(cp) = NULL
 
 #endif
diff --git a/misc/examples/coread.c b/misc/examples/coread.c
index 89e06b71..3d49c5df 100644
--- a/misc/examples/coread.c
+++ b/misc/examples/coread.c
@@ -35,7 +35,7 @@ int main(void) {
         printf("%3d %s\n", ++n, cstr_str(&z.line));
 
         // stop after 15 lines:
-        if (n == 15) cco_stop(&z);
+        if (n == 15) (void)cco_stop(&z);
     }
     printf("state %d\n", z.cco_state);
 }
diff --git a/misc/examples/coroutines.c b/misc/examples/coroutines.c
index 120f11b8..66a1275e 100644
--- a/misc/examples/coroutines.c
+++ b/misc/examples/coroutines.c
@@ -4,15 +4,13 @@
 
 // Use coroutine to create a fibonacci sequence generator:
 
-typedef long long intll_t;
-
 struct fibonacci {
     int n; 
     int cco_state;
-    intll_t a, b, idx;
+    int64_t a, b, idx;
 };
 
-intll_t fibonacci(struct fibonacci* F) {
+int64_t fibonacci(struct fibonacci* F) {
     assert (F->n < 95);
 
     cco_begin(F);
@@ -20,7 +18,7 @@ intll_t fibonacci(struct fibonacci* F) {
         F->b = 1;
         for (F->idx = 0; F->idx < F->n; F->idx++) {
             cco_yield(F->a);
-            intll_t sum = F->a + F->b; // NB! locals only lasts until next cco_yield!
+            int64_t sum = F->a + F->b; // NB! locals only lasts until next cco_yield!
             F->a = F->b;
             F->b = sum;
         }
@@ -50,16 +48,16 @@ bool iterate(struct iterate* I, struct fibonacci* F) {
             }
         }
         cco_final:
+            puts("final");
     cco_end();
     return false;
 }
 
 
 int main(void) {
-    printf("Fibonacci numbers:\n");
     struct fibonacci fib = {.n = 14};
-    struct iterate iter = {3, 3};
+    struct iterate it = {3, 3};
 
-    while (iterate(&iter, &fib))
-        printf("%d %d. Fib: %lld\n", iter.x, iter.y, fib.a);
+    while (iterate(&it, &fib))
+        printf("Iter=(%d, %d). Fib=%lld\n", it.x, it.y, (long long)fib.a);
 }