Added coroutines, based upon Simon Tatham's famous implementation. This version is much improved, but uses the same basic mechanisms.

2 files changed, 81 insertions, 0 deletions

diff --git a/misc/examples/cofib.c b/misc/examples/cofib.c
new file mode 100644
index 00000000..d0e4ac2a
--- /dev/null
+++ b/misc/examples/cofib.c
@@ -0,0 +1,40 @@
+#include <stc/algo/cco.h>
+#include <stdio.h>
+#include <stdint.h>
+
+// Use coroutine to create a fibonacci sequence generator:
+
+typedef long long llong;
+
+llong fibonacci_sequence(ccontext* ctx, unsigned n) {
+    assert (n < 95);
+
+    cco_context(ctx, 
+        llong a, b, idx;
+    );
+
+    cco_routine(u,
+        u->a = 0;
+        u->b = 1;
+        for (u->idx = 2; u->idx < n; u->idx++) {
+            llong sum = u->a + u->b;
+            cco_yield(sum);
+            u->a = u->b;
+            u->b = sum;
+        }
+        cco_finish:
+    );
+    return 0;
+}
+
+
+int main(void) {
+    ccontext z = 0;
+    printf("Fibonacci numbers:\n");
+    for (;;) {
+       llong x = fibonacci_sequence(&z, 30);
+       if (!z) break;
+       printf(" %lld", x);
+    }
+    puts("");
+}
diff --git a/misc/examples/coread.c b/misc/examples/coread.c
new file mode 100644
index 00000000..9181401d
--- /dev/null
+++ b/misc/examples/coread.c
@@ -0,0 +1,41 @@
+#include <stc/cstr.h>
+#include <stc/algo/cco.h>
+#include <errno.h>
+
+// Read file line by line using coroutines:
+
+cstr file_nextline(ccontext* ccx, const char* name)
+{
+    cco_context(ccx,
+        FILE* fp;
+        cstr line;
+    );
+
+    cco_routine(U,
+        U->fp = fopen(name, "r");
+        U->line = cstr_NULL;
+
+        while (cstr_getline(&U->line, U->fp))
+            cco_yield (cstr_clone(U->line));
+
+        cco_finish: // cco_finish is needed to support cco_stop.
+            printf("finish\n");
+            cstr_drop(&U->line);
+            fclose(U->fp);
+    );
+    return cstr_NULL;
+}
+
+
+int main(void) {
+    ccontext z = 0;
+    int n = 0;
+    do {
+        c_with (cstr line = file_nextline(&z, __FILE__), z, cstr_drop(&line)) {
+            printf("%3d %s\n", ++n, cstr_str(&line));
+
+            // stop after 10 lines:
+            if (n == 10) file_nextline(cco_stop(&z), __FILE__);
+        }
+    } while (z);
+}