Fix [d4e7780ca1681cd095dbd81fe264feff75c988f7|d4e7780ca1]: "global" cmd literal sharing vs. per-interp resolvers

9 files changed, 231 insertions, 34 deletions

diff --git a/generic/tclCompile.c b/generic/tclCompile.c
index c0203dd..f6b3c52 100644
--- a/generic/tclCompile.c
+++ b/generic/tclCompile.c
@@ -1781,9 +1781,17 @@ CompileCmdLiteral(
     CompileEnv *envPtr)
 {
     int numBytes;
-    const char *bytes = Tcl_GetStringFromObj(cmdObj, &numBytes);
-    int cmdLitIdx = TclRegisterNewCmdLiteral(envPtr, bytes, numBytes);
-    Command *cmdPtr = (Command *) Tcl_GetCommandFromObj(interp, cmdObj);
+    const char *bytes;
+    Command *cmdPtr;
+    int cmdLitIdx, extraLiteralFlags = LITERAL_CMD_NAME;
+
+    cmdPtr = (Command *) Tcl_GetCommandFromObj(interp, cmdObj);
+    if ((cmdPtr != NULL) && (cmdPtr->flags & CMD_VIA_RESOLVER)) {
+	extraLiteralFlags |= LITERAL_UNSHARED;
+    }
+
+    bytes = Tcl_GetStringFromObj(cmdObj, &numBytes);
+    cmdLitIdx = TclRegisterLiteral(envPtr, (char *)bytes, numBytes, extraLiteralFlags);
 
     if (cmdPtr) {
 	TclSetCmdNameObj(interp, TclFetchLiteral(envPtr, cmdLitIdx), cmdPtr);
diff --git a/generic/tclCompile.h b/generic/tclCompile.h
index d5bc86b..ba6ad44 100644
--- a/generic/tclCompile.h
+++ b/generic/tclCompile.h
@@ -1208,6 +1208,7 @@ MODULE_SCOPE int	TclPushProcCallFrame(ClientData clientData,
 
 #define LITERAL_ON_HEAP		0x01
 #define LITERAL_CMD_NAME	0x02
+#define LITERAL_UNSHARED	0x04
 
 /*
  * Form of TclRegisterLiteral with flags == 0. In that case, it is safe to
diff --git a/generic/tclEnsemble.c b/generic/tclEnsemble.c
index 8e5e410..6fedf29 100644
--- a/generic/tclEnsemble.c
+++ b/generic/tclEnsemble.c
@@ -3306,7 +3306,7 @@ CompileToInvokedCommand(
     Tcl_Token *tokPtr;
     Tcl_Obj *objPtr, **words;
     char *bytes;
-    int length, i, numWords, cmdLit;
+    int length, i, numWords, cmdLit, extraLiteralFlags = LITERAL_CMD_NAME;
     DefineLineInformation;
 
     /*
@@ -3349,7 +3349,10 @@ CompileToInvokedCommand(
     objPtr = Tcl_NewObj();
     Tcl_GetCommandFullName(interp, (Tcl_Command) cmdPtr, objPtr);
     bytes = Tcl_GetStringFromObj(objPtr, &length);
-    cmdLit = TclRegisterNewCmdLiteral(envPtr, bytes, length);
+    if ((cmdPtr != NULL) && (cmdPtr->flags & CMD_VIA_RESOLVER)) {
+	extraLiteralFlags |= LITERAL_UNSHARED;
+    }
+    cmdLit = TclRegisterLiteral(envPtr, (char *)bytes, length, extraLiteralFlags);
     TclSetCmdNameObj(interp, TclFetchLiteral(envPtr, cmdLit), cmdPtr);
     TclEmitPush(cmdLit, envPtr);
     TclDecrRefCount(objPtr);
diff --git a/generic/tclInt.h b/generic/tclInt.h
index 4f7ea6e..4d3c0b1 100644
--- a/generic/tclInt.h
+++ b/generic/tclInt.h
@@ -1677,11 +1677,13 @@ typedef struct Command {
  * (these last two flags are defined in tcl.h)
  */
 
-#define CMD_IS_DELETED		    0x1
-#define CMD_TRACE_ACTIVE	    0x2
-#define CMD_HAS_EXEC_TRACES	    0x4
-#define CMD_COMPILES_EXPANDED	    0x8
+#define CMD_IS_DELETED		    0x01
+#define CMD_TRACE_ACTIVE	    0x02
+#define CMD_HAS_EXEC_TRACES	    0x04
+#define CMD_COMPILES_EXPANDED	    0x08
 #define CMD_REDEF_IN_PROGRESS	    0x10
+#define CMD_VIA_RESOLVER	    0x20
+
 
 /*
  *----------------------------------------------------------------
diff --git a/generic/tclLiteral.c b/generic/tclLiteral.c
index 26c21db..aeb8213 100644
--- a/generic/tclLiteral.c
+++ b/generic/tclLiteral.c
@@ -214,7 +214,7 @@ TclCreateLiteral(
 	    if (globalPtrPtr) {
 		*globalPtrPtr = globalPtr;
 	    }
-	    if (flags & LITERAL_ON_HEAP) {
+	    if ((flags & LITERAL_ON_HEAP)) {
 		ckfree(bytes);
 	    }
 	    globalPtr->refCount++;
@@ -222,7 +222,7 @@ TclCreateLiteral(
 	}
     }
     if (!newPtr) {
-	if (flags & LITERAL_ON_HEAP) {
+	if ((flags & LITERAL_ON_HEAP)) {
 	    ckfree(bytes);
 	}
 	return NULL;
@@ -235,13 +235,23 @@ TclCreateLiteral(
 
     TclNewObj(objPtr);
     Tcl_IncrRefCount(objPtr);
-    if (flags & LITERAL_ON_HEAP) {
+    if ((flags & LITERAL_ON_HEAP)) {
 	objPtr->bytes = bytes;
 	objPtr->length = length;
     } else {
 	TclInitStringRep(objPtr, bytes, length);
     }
 
+    if ((flags & LITERAL_UNSHARED)) {
+	/*
+	 * Make clear, that no global value is returned
+	 */
+	if (globalPtrPtr != NULL) {
+	    *globalPtrPtr = NULL;
+	}
+	return objPtr;
+    }
+
 #ifdef TCL_COMPILE_DEBUG
     if (LookupLiteralEntry((Tcl_Interp *) iPtr, objPtr) != NULL) {
 	Tcl_Panic("%s: literal \"%.*s\" found globally but shouldn't be",
@@ -398,7 +408,7 @@ TclRegisterLiteral(
 	if ((objPtr->length == length) && ((length == 0)
 		|| ((objPtr->bytes[0] == bytes[0])
 		&& (memcmp(objPtr->bytes, bytes, (unsigned) length) == 0)))) {
-	    if (flags & LITERAL_ON_HEAP) {
+	    if ((flags & LITERAL_ON_HEAP)) {
 		ckfree(bytes);
 	    }
 	    objIndex = (localPtr - envPtr->literalArrayPtr);
@@ -417,7 +427,7 @@ TclRegisterLiteral(
      * the namespace as the interp's global NS.
      */
 
-    if (flags & LITERAL_CMD_NAME) {
+    if ((flags & LITERAL_CMD_NAME)) {
 	if ((length >= 2) && (bytes[0] == ':') && (bytes[1] == ':')) {
 	    nsPtr = iPtr->globalNsPtr;
 	} else {
@@ -1153,13 +1163,6 @@ TclVerifyLocalLiteralTable(
 			"TclVerifyLocalLiteralTable",
 			(length>60? 60 : length), bytes, localPtr->refCount);
 	    }
-	    if (LookupLiteralEntry((Tcl_Interp *) envPtr->iPtr,
-		    localPtr->objPtr) == NULL) {
-		bytes = Tcl_GetStringFromObj(localPtr->objPtr, &length);
-		Tcl_Panic("%s: local literal \"%.*s\" is not global",
-			"TclVerifyLocalLiteralTable",
-			(length>60? 60 : length), bytes);
-	    }
 	    if (localPtr->objPtr->bytes == NULL) {
 		Tcl_Panic("%s: literal has NULL string rep",
 			"TclVerifyLocalLiteralTable");
diff --git a/generic/tclNamesp.c b/generic/tclNamesp.c
index 5930859..a8d351f 100644
--- a/generic/tclNamesp.c
+++ b/generic/tclNamesp.c
@@ -2566,7 +2566,9 @@ Tcl_FindCommand(
 	}
 
 	if (result == TCL_OK) {
+	    ((Command *)cmd)->flags |= CMD_VIA_RESOLVER;
 	    return cmd;
+
 	} else if (result != TCL_CONTINUE) {
 	    return NULL;
 	}
@@ -2658,6 +2660,7 @@ Tcl_FindCommand(
     }
 
     if (cmdPtr != NULL) {
+	cmdPtr->flags  &= ~CMD_VIA_RESOLVER;
 	return (Tcl_Command) cmdPtr;
     }
 
diff --git a/generic/tclObj.c b/generic/tclObj.c
index 628c3a7..29c8e23 100644
--- a/generic/tclObj.c
+++ b/generic/tclObj.c
@@ -4219,7 +4219,10 @@ TclSetCmdNameObj(
     const char *name;
 
     if (objPtr->typePtr == &tclCmdNameType) {
-	return;
+	resPtr = objPtr->internalRep.twoPtrValue.ptr1;
+	if (resPtr != NULL && resPtr->cmdPtr == cmdPtr) {
+	    return;
+	}
     }
 
     cmdPtr->refCount++;
diff --git a/generic/tclTest.c b/generic/tclTest.c
index b3508f1..568dd01 100644
--- a/generic/tclTest.c
+++ b/generic/tclTest.c
@@ -7299,24 +7299,83 @@ InterpCmdResolver(
     CallFrame *varFramePtr = iPtr->varFramePtr;
     Proc *procPtr = (varFramePtr->isProcCallFrame & FRAME_IS_PROC) ?
             varFramePtr->procPtr : NULL;
-    Namespace *ns2NsPtr = (Namespace *)
-            Tcl_FindNamespace(interp, "::ns2", NULL, 0);
+    Namespace *callerNsPtr = varFramePtr->nsPtr;
+    Tcl_Command resolvedCmdPtr = NULL;
 
-    if (procPtr && (procPtr->cmdPtr->nsPtr == iPtr->globalNsPtr
-            || (ns2NsPtr && procPtr->cmdPtr->nsPtr == ns2NsPtr))) {
-        const char *callingCmdName =
+    /*
+     * Just do something special on a cmd literal "z" in two cases:
+     *  A)  when the caller is a proc "x", and the proc is either in "::" or in "::ns2".
+     *  B) the caller's namespace is "ctx1" or "ctx2"
+     */
+    if ( (name[0] == 'z') && (name[1] == '\0') ) {
+        Namespace *ns2NsPtr = (Namespace *) Tcl_FindNamespace(interp, "::ns2", NULL, 0);
+
+        if (procPtr != NULL
+            && ((procPtr->cmdPtr->nsPtr == iPtr->globalNsPtr)
+                || (ns2NsPtr != NULL && procPtr->cmdPtr->nsPtr == ns2NsPtr)
+                )
+            ) {
+            /*
+             * Case A)
+             *
+             *    - The context, in which this resolver becomes active, is
+             *      determined by the name of the caller proc, which has to be
+             *      named "x".
+             *
+             *    - To determine the name of the caller proc, the proc is taken
+             *      from the topmost stack frame.
+             *
+             *    - Note that the context is NOT provided during byte-code
+             *      compilation (e.g. in TclProcCompileProc)
+             *
+             *   When these conditions hold, this function resolves the
+             *   passed-in cmd literal into a cmd "y", which is taken from the
+             *   the global namespace (for simplicity).
+             */
+
+            const char *callingCmdName =
                 Tcl_GetCommandName(interp, (Tcl_Command) procPtr->cmdPtr);
 
-        if ((callingCmdName[0] == 'x') && (callingCmdName[1] == '\0')
-                && (name[0] == 'z') && (name[1] == '\0')) {
-            Tcl_Command sourceCmdPtr = Tcl_FindCommand(interp, "y", NULL,
-                    TCL_GLOBAL_ONLY);
+            if ( callingCmdName[0] == 'x' && callingCmdName[1] == '\0' ) {
+                resolvedCmdPtr = Tcl_FindCommand(interp, "y", NULL, TCL_GLOBAL_ONLY);
+            }
+        } else if (callerNsPtr != NULL) {
+            /*
+             * Case B)
+             *
+             *    - The context, in which this resolver becomes active, is
+             *      determined by the name of the parent namespace, which has
+             *      to be named "ctx1" or "ctx2".
+             *
+             *    - To determine the name of the parent namesace, it is taken
+             *      from the 2nd highest stack frame.
+             *
+             *    - Note that the context can be provided during byte-code
+             *      compilation (e.g. in TclProcCompileProc)
+             *
+             *   When these conditions hold, this function resolves the
+             *   passed-in cmd literal into a cmd "y" or "Y" depending on the
+             *   context. The resolved procs are taken from the the global
+             *   namespace (for simplicity).
+             */
+
+            CallFrame *parentFramePtr = varFramePtr->callerPtr;
+            char *context = parentFramePtr != NULL ? parentFramePtr->nsPtr->name : "(NULL)";
 
-            if (sourceCmdPtr != NULL) {
-                *rPtr = sourceCmdPtr;
-                return TCL_OK;
+            if (strcmp(context, "ctx1") == 0 && (name[0] == 'z') && (name[1] == '\0')) {
+                resolvedCmdPtr = Tcl_FindCommand(interp, "y", NULL, TCL_GLOBAL_ONLY);
+                /* fprintf(stderr, "... y ==> %p\n", resolvedCmdPtr);*/
+
+            } else if (strcmp(context, "ctx2") == 0 && (name[0] == 'z') && (name[1] == '\0')) {
+                resolvedCmdPtr = Tcl_FindCommand(interp, "Y", NULL, TCL_GLOBAL_ONLY);
+                /*fprintf(stderr, "... Y ==> %p\n", resolvedCmdPtr);*/
             }
         }
+
+        if (resolvedCmdPtr != NULL) {
+            *rPtr = resolvedCmdPtr;
+            return TCL_OK;
+        }
     }
     return TCL_CONTINUE;
 }
diff --git a/tests/resolver.test b/tests/resolver.test
index aaad02c..9bb4c08 100644
--- a/tests/resolver.test
+++ b/tests/resolver.test
@@ -196,6 +196,121 @@ test resolver-2.1 {compiled var resolver: Bug #3383616} -setup {
 } -cleanup {
     testinterpresolver down
 } -result {}
+
+
+#
+# The test resolver-3.1* test bad interactions of resolvers on the "global"
+# (per interp) literal pools. A resolver might resolve a cmd literal depending
+# on a context differently, whereas the cmd literal sharing assumed that the
+# namespace containing the literal solely determines the resolved cmd (and is
+# resolver-agnostic).
+#
+# In order to make the test cases for the per-interpreter cmd literal pool
+# reproducable and to minimize interactions between test cases, we use a slave
+# interpreter per test-case.
+#
+#
+# Testing resolver in namespace-based context "ctx1"
+#
+test resolver-3.1a {
+    interp command resolver,
+    resolve literal "z" in proc "x1" in context "ctx1"
+} -setup {
+
+    interp create i0
+    testinterpresolver up i0
+    i0 eval {
+	proc y {} { return yy }
+	namespace eval ::ns {
+	    proc x1 {} { z }
+	}
+    }
+} -constraints testinterpresolver -body {
+
+    set r [i0 eval {namespace eval ::ctx1 {
+	::ns::x1
+    }}]
+
+    return $r
+} -cleanup {
+    testinterpresolver down i0
+    interp delete i0
+} -result {yy}
+
+#
+# Testing resolver in namespace-based context "ctx2"
+#
+test resolver-3.1b {
+    interp command resolver,
+    resolve literal "z" in proc "x2" in context "ctx2"
+} -setup {
+
+    interp create i0
+    testinterpresolver up i0
+    i0 eval {
+	proc Y {} { return YY }
+	namespace eval ::ns {
+	    proc x2 {} { z }
+	}
+    }
+} -constraints testinterpresolver -body {
+
+    set r [i0 eval {namespace eval ::ctx2 {
+	::ns::x2
+    }}]
+
+    return $r
+} -cleanup {
+    testinterpresolver down i0
+    interp delete i0
+} -result {YY}
+
+#
+# Testing resolver in namespace-based context "ctx1" and "ctx2" in the same
+# interpreter.
+#
+
+test resolver-3.1c {
+    interp command resolver,
+    resolve literal "z" in proc "x1" in context "ctx1",
+    resolve literal "z" in proc "x2" in context "ctx2"
+
+    Test, whether the shared cmd literal created by the first byte-code
+    compilation interacts with the second one.
+} -setup {
+
+    interp create i0
+    testinterpresolver up i0
+
+    i0 eval {
+	proc y {} { return yy }
+	proc Y {} { return YY }
+	namespace eval ::ns {
+	    proc x1 {} { z }
+	    proc x2 {} { z }
+	}
+    }
+
+} -constraints testinterpresolver -body {
+
+    set r1 [i0 eval {namespace eval ::ctx1 {
+	::ns::x1
+    }}]
+
+    set r2 [i0 eval {namespace eval ::ctx2 {
+	::ns::x2
+    }}]
+
+    set r3 [i0 eval {namespace eval ::ctx1 {
+	::ns::x1
+    }}]
+
+    return [list $r1 $r2 $r3]
+} -cleanup {
+    testinterpresolver down i0
+    interp delete i0
+} -result {yy YY yy}
+
 
 cleanupTests
 return