From cc2a60ecb7e4c57ed31e5c5c3f49d8dc7447acc5 Mon Sep 17 00:00:00 2001 From: Roberto Ierusalimschy Date: Fri, 8 Jun 2012 12:14:04 -0300 Subject: [PATCH] bugs in yields inside debug hooks --- lapi.c | 4 ++-- ldo.c | 8 ++++---- lstate.h | 5 +++-- lvm.c | 19 ++++++++++++++----- 4 files changed, 23 insertions(+), 13 deletions(-) diff --git a/lapi.c b/lapi.c index 9201aac4..b82706fd 100644 --- a/lapi.c +++ b/lapi.c @@ -1,5 +1,5 @@ /* -** $Id: lapi.c,v 2.162 2012/05/22 17:50:39 roberto Exp roberto $ +** $Id: lapi.c,v 2.163 2012/05/23 15:42:27 roberto Exp roberto $ ** Lua API ** See Copyright Notice in lua.h */ @@ -950,7 +950,7 @@ LUA_API int lua_pcallk (lua_State *L, int nargs, int nresults, int errfunc, ci->u.c.k = k; /* save continuation */ ci->u.c.ctx = ctx; /* save context */ /* save information for error recovery */ - ci->u.c.extra = savestack(L, c.func); + ci->extra = savestack(L, c.func); ci->u.c.old_allowhook = L->allowhook; ci->u.c.old_errfunc = L->errfunc; L->errfunc = func; diff --git a/ldo.c b/ldo.c index f3121fd0..9e1a5b00 100644 --- a/ldo.c +++ b/ldo.c @@ -1,5 +1,5 @@ /* -** $Id: ldo.c,v 2.103 2012/04/26 20:41:18 roberto Exp roberto $ +** $Id: ldo.c,v 2.104 2012/05/08 13:53:33 roberto Exp roberto $ ** Stack and Call structure of Lua ** See Copyright Notice in lua.h */ @@ -451,7 +451,7 @@ static int recover (lua_State *L, int status) { CallInfo *ci = findpcall(L); if (ci == NULL) return 0; /* no recovery point */ /* "finish" luaD_pcall */ - oldtop = restorestack(L, ci->u.c.extra); + oldtop = restorestack(L, ci->extra); luaF_close(L, oldtop); seterrorobj(L, status, oldtop); L->ci = ci; @@ -498,10 +498,10 @@ static void resume (lua_State *L, void *ud) { resume_error(L, "cannot resume dead coroutine", firstArg); else { /* resuming from previous yield */ L->status = LUA_OK; + ci->func = restorestack(L, ci->extra); if (isLua(ci)) /* yielded inside a hook? */ luaV_execute(L); /* just continue running Lua code */ else { /* 'common' yield */ - ci->func = restorestack(L, ci->u.c.extra); if (ci->u.c.k != NULL) { /* does it have a continuation? */ int n; ci->u.c.status = LUA_YIELD; /* 'default' status */ @@ -563,13 +563,13 @@ LUA_API int lua_yieldk (lua_State *L, int nresults, int ctx, lua_CFunction k) { luaG_runerror(L, "attempt to yield from outside a coroutine"); } L->status = LUA_YIELD; + ci->extra = savestack(L, ci->func); /* save current 'func' */ if (isLua(ci)) { /* inside a hook? */ api_check(L, k == NULL, "hooks cannot continue after yielding"); } else { if ((ci->u.c.k = k) != NULL) /* is there a continuation? */ ci->u.c.ctx = ctx; /* save context */ - ci->u.c.extra = savestack(L, ci->func); /* save current 'func' */ ci->func = L->top - nresults - 1; /* protect stack below results */ luaD_throw(L, LUA_YIELD); } diff --git a/lstate.h b/lstate.h index 665cf160..5c6bd67b 100644 --- a/lstate.h +++ b/lstate.h @@ -1,5 +1,5 @@ /* -** $Id: lstate.h,v 2.79 2012/05/22 17:32:25 roberto Exp roberto $ +** $Id: lstate.h,v 2.80 2012/05/22 17:50:39 roberto Exp roberto $ ** Global State ** See Copyright Notice in lua.h */ @@ -72,6 +72,7 @@ typedef struct CallInfo { struct CallInfo *previous, *next; /* dynamic call link */ short nresults; /* expected number of results from this function */ lu_byte callstatus; + ptrdiff_t extra; union { struct { /* only for Lua functions */ StkId base; /* base for this function */ @@ -81,7 +82,6 @@ typedef struct CallInfo { int ctx; /* context info. in case of yields */ lua_CFunction k; /* continuation in case of yields */ ptrdiff_t old_errfunc; - ptrdiff_t extra; lu_byte old_allowhook; lu_byte status; } c; @@ -100,6 +100,7 @@ typedef struct CallInfo { #define CIST_YPCALL (1<<4) /* call is a yieldable protected call */ #define CIST_STAT (1<<5) /* call has an error status (pcall) */ #define CIST_TAIL (1<<6) /* call was tail called */ +#define CIST_HOOKYIELD (1<<7) /* last hook called yielded */ #define isLua(ci) ((ci)->callstatus & CIST_LUA) diff --git a/lvm.c b/lvm.c index cd7642eb..2d27d512 100644 --- a/lvm.c +++ b/lvm.c @@ -1,5 +1,5 @@ /* -** $Id: lvm.c,v 2.150 2012/05/08 13:53:33 roberto Exp roberto $ +** $Id: lvm.c,v 2.151 2012/05/14 17:50:49 roberto Exp roberto $ ** Lua virtual machine ** See Copyright Notice in lua.h */ @@ -60,10 +60,15 @@ int luaV_tostring (lua_State *L, StkId obj) { static void traceexec (lua_State *L) { CallInfo *ci = L->ci; lu_byte mask = L->hookmask; - if ((mask & LUA_MASKCOUNT) && L->hookcount == 0) { - resethookcount(L); - luaD_hook(L, LUA_HOOKCOUNT, -1); + int counthook = ((mask & LUA_MASKCOUNT) && L->hookcount == 0); + if (counthook) + resethookcount(L); /* reset count */ + if (ci->callstatus & CIST_HOOKYIELD) { /* called hook last time? */ + ci->callstatus &= ~CIST_HOOKYIELD; /* erase mark */ + return; /* do not call hook again (VM yielded, so it did not move) */ } + if (counthook) + luaD_hook(L, LUA_HOOKCOUNT, -1); /* call count hook */ if (mask & LUA_MASKLINE) { Proto *p = ci_func(ci)->p; int npc = pcRel(ci->u.l.savedpc, p); @@ -71,11 +76,15 @@ static void traceexec (lua_State *L) { if (npc == 0 || /* call linehook when enter a new function, */ ci->u.l.savedpc <= L->oldpc || /* when jump back (loop), or when */ newline != getfuncline(p, pcRel(L->oldpc, p))) /* enter a new line */ - luaD_hook(L, LUA_HOOKLINE, newline); + luaD_hook(L, LUA_HOOKLINE, newline); /* call line hook */ } L->oldpc = ci->u.l.savedpc; if (L->status == LUA_YIELD) { /* did hook yield? */ + if (counthook) + L->hookcount = 1; /* undo decrement to zero */ ci->u.l.savedpc--; /* undo increment (resume will increment it again) */ + ci->callstatus |= CIST_HOOKYIELD; /* mark that it yieled */ + ci->func = L->top - 1; /* protect stack below results */ luaD_throw(L, LUA_YIELD); } }