commit 118347d8c3b83ea0291918e81c5367937316fabb
parent 6820da509686ce06fdb3de58856056476f55f534
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Wed, 6 Nov 2002 17:07:38 -0200
new API for coroutines
Diffstat:
| M | lapi.c | | | 15 | ++++++++++++++- |
| M | lbaselib.c | | | 46 | ++++++++++++++++++++++++---------------------- |
| M | ldo.c | | | 97 | +++++++++++++++++++++++++++++++------------------------------------------------ |
| M | lstate.h | | | 5 | +++-- |
| M | lua.h | | | 7 | ++++--- |
| M | lvm.c | | | 3 | ++- |
6 files changed, 85 insertions(+), 88 deletions(-)
diff --git a/lapi.c b/lapi.c
@@ -1,5 +1,5 @@
/*
-** $Id: lapi.c,v 1.214 2002/10/25 20:05:28 roberto Exp roberto $
+** $Id: lapi.c,v 1.215 2002/10/25 21:31:28 roberto Exp roberto $
** Lua API
** See Copyright Notice in lua.h
*/
@@ -105,6 +105,19 @@ LUA_API int lua_checkstack (lua_State *L, int size) {
}
+LUA_API void lua_movethread (lua_State *from, lua_State *to, int n) {
+ int i;
+ lua_lock(to);
+ api_checknelems(from, n);
+ from->top -= n;
+ for (i = 0; i < n; i++) {
+ setobj(to->top, from->top + i);
+ api_incr_top(to);
+ }
+ lua_unlock(to);
+}
+
+
LUA_API lua_CFunction lua_atpanic (lua_State *L, lua_CFunction panicf) {
lua_CFunction old;
lua_lock(L);
diff --git a/lbaselib.c b/lbaselib.c
@@ -1,5 +1,5 @@
/*
-** $Id: lbaselib.c,v 1.102 2002/10/25 21:31:28 roberto Exp roberto $
+** $Id: lbaselib.c,v 1.103 2002/10/25 21:36:54 roberto Exp roberto $
** Basic library
** See Copyright Notice in lua.h
*/
@@ -557,12 +557,23 @@ static const luaL_reg base_funcs[] = {
** =======================================================
*/
-
-static int luaB_auxresume (lua_State *L, lua_State *co) {
+static int auxresume (lua_State *L, lua_State *co, int narg) {
int status;
- int oldtop = lua_gettop(L);
- status = lua_resume(L, co);
- return (status != 0) ? -1 : lua_gettop(L) - oldtop;
+ if (!lua_checkstack(co, narg))
+ luaL_error(L, "too many arguments to resume");
+ lua_movethread(L, co, narg);
+ status = lua_resume(co, narg);
+ if (status == 0) {
+ int nres = lua_gettop(co);
+ if (!lua_checkstack(L, narg))
+ luaL_error(L, "too many results to resume");
+ lua_movethread(co, L, nres); /* move yielded values */
+ return nres;
+ }
+ else {
+ lua_movethread(co, L, 1); /* move error message */
+ return -1; /* error flag */
+ }
}
@@ -570,7 +581,7 @@ static int luaB_coresume (lua_State *L) {
lua_State *co = lua_tothread(L, 1);
int r;
luaL_arg_check(L, co, 1, "coroutine/thread expected");
- r = luaB_auxresume(L, co);
+ r = auxresume(L, co, lua_gettop(L) - 1);
if (r < 0) {
lua_pushboolean(L, 0);
lua_insert(L, -2);
@@ -585,28 +596,19 @@ static int luaB_coresume (lua_State *L) {
static int luaB_auxwrap (lua_State *L) {
- int r = luaB_auxresume(L, lua_tothread(L, lua_upvalueindex(1)));
- if (r < 0) lua_error(L);
+ lua_State *co = lua_tothread(L, lua_upvalueindex(1));
+ int r = auxresume(L, co, lua_gettop(L));
+ if (r < 0) lua_error(L); /* propagate error */
return r;
}
static int luaB_cocreate (lua_State *L) {
- lua_State *NL;
- int ref;
- int i;
- int n = lua_gettop(L);
+ lua_State *NL = lua_newthread(L);
luaL_arg_check(L, lua_isfunction(L, 1) && !lua_iscfunction(L, 1), 1,
"Lua function expected");
- NL = lua_newthread(L);
- /* move function and arguments from L to NL */
- for (i = 1; i <= n; i++) {
- lua_pushvalue(L, i);
- ref = lua_ref(L, 1);
- lua_getref(NL, ref);
- lua_unref(L, ref);
- }
- lua_cobegin(NL, n-1);
+ lua_pushvalue(L, 1); /* move function to top */
+ lua_movethread(L, NL, 1); /* move function from L to NL */
return 1;
}
diff --git a/ldo.c b/ldo.c
@@ -1,5 +1,5 @@
/*
-** $Id: ldo.c,v 1.196 2002/10/09 13:42:01 roberto Exp roberto $
+** $Id: ldo.c,v 1.197 2002/10/25 20:05:28 roberto Exp roberto $
** Stack and Call structure of Lua
** See Copyright Notice in lua.h
*/
@@ -44,22 +44,23 @@ struct lua_longjmp {
};
-static void seterrorobj (lua_State *L, int errcode) {
+static void seterrorobj (lua_State *L, int errcode, StkId oldtop) {
switch (errcode) {
case LUA_ERRMEM: {
- setsvalue(L->top, luaS_new(L, MEMERRMSG));
+ setsvalue(oldtop, luaS_new(L, MEMERRMSG));
break;
}
case LUA_ERRERR: {
- setsvalue(L->top, luaS_new(L, "error in error handling"));
+ setsvalue(oldtop, luaS_new(L, "error in error handling"));
break;
}
case LUA_ERRSYNTAX:
case LUA_ERRRUN: {
- return; /* error message already on top */
+ setobj(oldtop, L->top - 1); /* error message on current top */
+ break;
}
}
- L->top++;
+ L->top = oldtop + 1;
}
@@ -298,67 +299,46 @@ void luaD_call (lua_State *L, StkId func, int nResults) {
}
-LUA_API void lua_cobegin (lua_State *L, int nargs) {
- lua_lock(L);
- luaD_precall(L, L->top - (nargs+1));
- lua_unlock(L);
-}
-
-
-static void move_results (lua_State *L, TObject *from, TObject *to) {
- while (from < to) {
- setobj(L->top, from);
- from++;
- incr_top(L);
- }
-}
-
-
static void resume (lua_State *L, void *ud) {
StkId firstResult;
+ int nargs = *cast(int *, ud);
CallInfo *ci = L->ci;
- if (ci->state & CI_C) { /* not first time (i.e. inside a yield)? */
+ if (ci == L->base_ci) { /* no activation record? */
+ if (nargs >= L->top - L->ci->base)
+ luaG_runerror(L, "cannot resume dead coroutine");
+ luaD_precall(L, L->top - (nargs + 1)); /* start coroutine */
+ }
+ else if (ci->state && CI_YIELD) { /* inside a yield? */
/* finish interrupted execution of `OP_CALL' */
int nresults;
lua_assert((ci-1)->state & CI_SAVEDPC);
lua_assert(GET_OPCODE(*((ci-1)->u.l.savedpc - 1)) == OP_CALL ||
GET_OPCODE(*((ci-1)->u.l.savedpc - 1)) == OP_TAILCALL);
nresults = GETARG_C(*((ci-1)->u.l.savedpc - 1)) - 1;
- luaD_poscall(L, nresults, L->top); /* complete it */
+ luaD_poscall(L, nresults, L->top - nargs); /* complete it */
if (nresults >= 0) L->top = L->ci->top;
}
+ else
+ luaG_runerror(L, "cannot resume non-suspended coroutine");
firstResult = luaV_execute(L);
- if (firstResult == NULL) /* yield? */
- *cast(int *, ud) = L->ci->u.c.yield_results;
- else { /* return */
- *cast(int *, ud) = L->top - firstResult;
+ if (firstResult != NULL) /* return? */
luaD_poscall(L, LUA_MULTRET, firstResult); /* finalize this coroutine */
- }
}
-LUA_API int lua_resume (lua_State *L, lua_State *co) {
- CallInfo *ci;
- int numres;
+LUA_API int lua_resume (lua_State *L, int nargs) {
int status;
+ int old_allowhooks;
lua_lock(L);
- ci = co->ci;
- if (ci == co->base_ci) { /* no activation record? ?? */
- luaO_pushfstring(L, "cannot resume dead thread");
- status = LUA_ERRRUN;
- }
- else if (co->errorJmp != NULL) { /* ?? */
- luaO_pushfstring(L, "cannot resume active thread");
- status = LUA_ERRRUN;
- }
- else {
- status = luaD_rawrunprotected(co, resume, &numres);
- if (status == 0)
- move_results(L, co->top - numres, co->top);
- else {
- setobj(L->top++, co->top - 1); /* move error message to other stack */
- co->ci = co->base_ci; /* `kill' thread */
- }
+ old_allowhooks = allowhook(L);
+ lua_assert(L->errfunc == 0);
+ status = luaD_rawrunprotected(L, resume, &nargs);
+ if (status != 0) {
+ L->ci = L->base_ci; /* `kill' thread (??) */
+ seterrorobj(L, status, L->ci->base);
+ luaF_close(L, L->top); /* close eventual pending closures */
+ setallowhook(L, old_allowhooks);
+ restore_stack_limit(L);
}
lua_unlock(L);
return status;
@@ -372,7 +352,12 @@ LUA_API int lua_yield (lua_State *L, int nresults) {
if ((ci-1)->state & CI_C)
luaG_runerror(L, "cannot yield a C function");
lua_assert(ci->state & CI_C); /* current function is not Lua */
- ci->u.c.yield_results = nresults;
+ if (L->top - nresults > ci->base) { /* is there garbage in the stack? */
+ int i;
+ for (i=0; i<nresults; i++) /* move down results */
+ setobj(ci->base + i, L->top - nresults + i);
+ L->top = ci->base + nresults;
+ }
lua_unlock(L);
return -1;
}
@@ -405,12 +390,8 @@ int luaD_pcall (lua_State *L, int nargs, int nresults, ptrdiff_t errfunc) {
c.nresults = nresults;
status = luaD_rawrunprotected(L, &f_call, &c);
if (status != 0) { /* an error occurred? */
- StkId err; /* error msg. position */
- seterrorobj(L, status);
- err = L->top - 1;
- /* remove parameters and func from the stack */
- L->top = restorestack(L, old_top) - (nargs+1);
- setobj(L->top++, err); /* copy error message to corrected top */
+ StkId oldtop = restorestack(L, old_top) - (nargs+1);
+ seterrorobj(L, status, oldtop);
luaF_close(L, L->top); /* close eventual pending closures */
L->ci = restoreci(L, old_ci);
setallowhook(L, old_allowhooks);
@@ -461,9 +442,7 @@ int luaD_protectedparser (lua_State *L, ZIO *z, int bin) {
}
else { /* error */
StkId oldtop = restorestack(L, oldtopr);
- seterrorobj(L, status);
- setobj(oldtop, L->top - 1); /* copy error message to old top */
- L->top = oldtop+1;
+ seterrorobj(L, status, oldtop);
}
return status;
}
diff --git a/lstate.h b/lstate.h
@@ -1,5 +1,5 @@
/*
-** $Id: lstate.h,v 1.98 2002/10/22 17:58:14 roberto Exp roberto $
+** $Id: lstate.h,v 1.99 2002/10/25 20:05:28 roberto Exp roberto $
** Global State
** See Copyright Notice in lua.h
*/
@@ -83,7 +83,7 @@ typedef struct CallInfo {
StkId *pb; /* points to `base' variable in `luaV_execute' */
} l;
struct { /* for C functions */
- int yield_results;
+ int dummy; /* just to avoid an empty struct */
} c;
} u;
} CallInfo;
@@ -99,6 +99,7 @@ typedef struct CallInfo {
`pc' is being used by the other, and therefore CI_SAVEDPC is 1 too) */
#define CI_CALLING 4
#define CI_SAVEDPC 8 /* 1 if `savedpc' is updated */
+#define CI_YIELD 16 /* 1 if thread is suspended */
#define ci_func(ci) (clvalue((ci)->base - 1))
diff --git a/lua.h b/lua.h
@@ -1,5 +1,5 @@
/*
-** $Id: lua.h,v 1.160 2002/10/25 20:05:28 roberto Exp roberto $
+** $Id: lua.h,v 1.161 2002/10/25 21:31:28 roberto Exp roberto $
** Lua - An Extensible Extension Language
** Tecgraf: Computer Graphics Technology Group, PUC-Rio, Brazil
** http://www.lua.org mailto:info@lua.org
@@ -123,6 +123,8 @@ LUA_API void lua_insert (lua_State *L, int idx);
LUA_API void lua_replace (lua_State *L, int idx);
LUA_API int lua_checkstack (lua_State *L, int sz);
+LUA_API void lua_movethread (lua_State *from, lua_State *to, int n);
+
/*
** access functions (stack -> C)
@@ -201,9 +203,8 @@ LUA_API int lua_dump (lua_State *L, lua_Chunkwriter writer, void *data);
/*
** coroutine functions
*/
-LUA_API void lua_cobegin (lua_State *L, int nargs);
LUA_API int lua_yield (lua_State *L, int nresults);
-LUA_API int lua_resume (lua_State *L, lua_State *co);
+LUA_API int lua_resume (lua_State *L, int narg);
/*
** Garbage-collection functions
diff --git a/lvm.c b/lvm.c
@@ -1,5 +1,5 @@
/*
-** $Id: lvm.c,v 1.257 2002/10/08 18:46:08 roberto Exp roberto $
+** $Id: lvm.c,v 1.258 2002/10/25 20:05:28 roberto Exp roberto $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -592,6 +592,7 @@ StkId luaV_execute (lua_State *L) {
if (firstResult > L->top) { /* yield? */
(L->ci - 1)->u.l.savedpc = pc;
(L->ci - 1)->state = CI_SAVEDPC;
+ L->ci->state |= CI_YIELD;
return NULL;
}
/* it was a C function (`precall' called it); adjust results */
