From 99b8ba83770da7250fa735b46c3cff40d142c94e Mon Sep 17 00:00:00 2001
From: Konstantin Osipov <kostja.osipov@gmail.com>
Date: Wed, 15 Feb 2012 02:03:56 +0400
Subject: [PATCH] Blueprint 'lua-fiber-status': review comments.
Update style, add comments.
---
core/fiber.m | 6 +++++-
core/tarantool_lua.m | 42 +++++++++++++++++++++++-------------------
2 files changed, 28 insertions(+), 20 deletions(-)
diff --git a/core/fiber.m b/core/fiber.m
index c727f9fb29..6dba8ff44b 100644
--- a/core/fiber.m
+++ b/core/fiber.m
@@ -251,10 +251,14 @@ fiber_yield(void)
coro_transfer(&caller->coro.ctx, &callee->coro.ctx);
}
+/**
+ * Return true if the current fiber is a callee of fiber f,
+ * false otherwise.
+ */
bool
fiber_is_caller(struct fiber *f)
{
- /* 'unwinding' fiber's stack */
+ /* 'Unwinding' the fiber stack. */
for (struct fiber **sp_ptr = sp; sp_ptr > call_stack; --sp_ptr) {
if (f == *sp_ptr)
return true;
diff --git a/core/tarantool_lua.m b/core/tarantool_lua.m
index ca9ae097dd..f6e26c256a 100644
--- a/core/tarantool_lua.m
+++ b/core/tarantool_lua.m
@@ -518,32 +518,36 @@ lbox_fiber_yield(struct lua_State *L)
}
/**
- * Get fiber status
+ * Get fiber status.
+ * This follows the rules of Lua coroutine.status() function:
+ * Returns the status of fibier, as a string:
+ * - "running", if the fiber is running (that is, it called status);
+ * - "suspended", if the fiber is suspended in a call to yield(),
+ * or if it has not started running yet;
+ * - "normal" if the fiber is active but not running (that is,
+ * it has resumed another fiber);
+ * - "dead" if the fiber has finished its body function, or if it
+ * has stopped with an error.
*/
static int
lbox_fiber_status(struct lua_State *L)
{
struct fiber *f = lbox_checkfiber(L, 1);
+ const char *status;
if (f->fid == 0) {
- /* this fiber is dead */
- lua_pushstring(L, "dead");
- return 1;
- }
-
- if (f == fiber) {
- /* the fiber is current running fiber */
- lua_pushstring(L, "running");
- return 1;
+ /* This fiber is dead. */
+ status = "dead";
+ } else if (f == fiber) {
+ /* The fiber is the current running fiber. */
+ status = "running";
+ } else if (fiber_is_caller(f)) {
+ /* The fiber is current fiber's caller. */
+ status = "normal";
+ } else {
+ /* None of the above: must be suspended. */
+ status = "suspended";
}
-
- if (fiber_is_caller(f)) {
- /* the fiber is current fiber caller */
- lua_pushstring(L, "normal");
- return 1;
- }
-
- /* the fiber is sleeping */
- lua_pushstring(L, "suspended");
+ lua_pushstring(L, status);
return 1;
}
--
GitLab