hooks

1 files changed, 37 insertions, 1 deletions

diff --git a/src/ldo.js b/src/ldo.js
index 6a74cad..0fcbf0e 100644
--- a/src/ldo.js
+++ b/src/ldo.js
@@ -73,7 +73,8 @@ const luaD_precall = function(L, off, nresults) {
             ci.funcOff = off;
             ci.top = L.top + lua.LUA_MINSTACK;
             ci.callstatus = 0;
-            // TODO: hook
+            if (L.hookmask & lua.LUA_MASKCALL)
+                luaD_hook(L, lua.LUA_HOOKCALL, -1);
             let n = f(L); /* do the actual call */
 
             assert(n < L.top - L.ci.funcOff, "not enough elements in the stack");
@@ -129,6 +130,13 @@ const luaD_precall = function(L, off, nresults) {
 
 const luaD_poscall = function(L, ci, firstResult, nres) {
     let wanted = ci.nresults;
+
+    if (L.hookmask & (lua.LUA_MASKRET | lua.LUA_MASKLINE)) {
+        if (L.hookmask & lua.LUA_MASKRET)
+            luaD_hook(L, lua.LUA_HOOKRET, -1);
+        L.oldpc = ci.previous.pcOff;  /* 'oldpc' for caller function */
+    }
+
     let res = ci.funcOff;
     L.ci = ci.previous;
     L.ciOff--;
@@ -171,6 +179,33 @@ const moveresults = function(L, firstResult, res, nres, wanted) {
     return true;
 };
 
+/*
+** Call a hook for the given event. Make sure there is a hook to be
+** called. (Both 'L->hook' and 'L->hookmask', which triggers this
+** function, can be changed asynchronously by signals.)
+*/
+const luaD_hook = function(L, event, line) {
+    let hook = L.hook;
+    if (hook && L.allowhook) {  /* make sure there is a hook */
+        let ci = L.ci;
+        let top = L.top;
+        let ci_top = ci.top;
+        let ar = new lua.lua_Debug();
+        ar.event = event;
+        ar.currentline = line;
+        ar.i_ci = ci;
+        ci.top = L.top + lua.LUA_MINSTACK;
+        L.allowhook = 0;  /* cannot call hooks inside a hook */
+        ci.callstatus |= lstate.CIST_HOOKED;
+        hook(L, ar);
+        assert(!L.allowhook);
+        L.allowhook = 1;
+        ci.top = ci_top;
+        L.top = top;
+        ci.callstatus &= ~lstate.CIST_HOOKED;
+    }
+};
+
 const adjust_varargs = function(L, p, actual) {
     let nfixargs = p.numparams;
     /* move fixed parameters to final position */
@@ -566,6 +601,7 @@ module.exports.SParser              = SParser;
 module.exports.adjust_varargs       = adjust_varargs;
 module.exports.luaD_call            = luaD_call;
 module.exports.luaD_callnoyield     = luaD_callnoyield;
+module.exports.luaD_hook            = luaD_hook;
 module.exports.luaD_pcall           = luaD_pcall;
 module.exports.luaD_poscall         = luaD_poscall;
 module.exports.luaD_precall         = luaD_precall;