/** $Id: VDScriptInterp.cpp 46003 2013-05-13 08:44:23Z vboxsync $ */ /** @file * * VBox HDD container test utility - scripting engine, interpreter. */ /* * Copyright (C) 2013 Oracle Corporation * * This file is part of VirtualBox Open Source Edition (OSE), as * available from http://www.virtualbox.org. This file is free software; * you can redistribute it and/or modify it under the terms of the GNU * General Public License (GPL) as published by the Free Software * Foundation, in version 2 as it comes in the "COPYING" file of the * VirtualBox OSE distribution. VirtualBox OSE is distributed in the * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind. */ #define LOGGROUP LOGGROUP_DEFAULT #include #include #include #include #include #include #include "VDScriptAst.h" #include "VDScriptStack.h" #include "VDScriptInternal.h" /** * Interpreter variable. */ typedef struct VDSCRIPTINTERPVAR { /** String space core. */ RTSTRSPACECORE Core; /** Value. */ VDSCRIPTARG Value; } VDSCRIPTINTERPVAR; /** Pointer to an interpreter variable. */ typedef VDSCRIPTINTERPVAR *PVDSCRIPTINTERPVAR; /** * Block scope. */ typedef struct VDSCRIPTINTERPSCOPE { /** Pointer to the enclosing scope if available. */ struct VDSCRIPTINTERPSCOPE *pParent; /** String space of declared variables in this scope. */ RTSTRSPACE hStrSpaceVar; } VDSCRIPTINTERPSCOPE; /** Pointer to a scope block. */ typedef VDSCRIPTINTERPSCOPE *PVDSCRIPTINTERPSCOPE; /** * Function call. */ typedef struct VDSCRIPTINTERPFNCALL { /** Pointer to the caller of this function. */ struct VDSCRIPTINTERPFNCALL *pCaller; /** Root scope of this function. */ VDSCRIPTINTERPSCOPE ScopeRoot; /** Current scope in this function. */ PVDSCRIPTINTERPSCOPE pScopeCurr; } VDSCRIPTINTERPFNCALL; /** Pointer to a function call. */ typedef VDSCRIPTINTERPFNCALL *PVDSCRIPTINTERPFNCALL; /** * Interpreter context. */ typedef struct VDSCRIPTINTERPCTX { /** Pointer to the script context. */ PVDSCRIPTCTXINT pScriptCtx; /** Current function call entry. */ PVDSCRIPTINTERPFNCALL pFnCallCurr; /** Stack of calculated values. */ VDSCRIPTSTACK StackValues; /** Evaluation control stack. */ VDSCRIPTSTACK StackCtrl; } VDSCRIPTINTERPCTX; /** Pointer to an interpreter context. */ typedef VDSCRIPTINTERPCTX *PVDSCRIPTINTERPCTX; /** * Interpreter control type. */ typedef enum VDSCRIPTINTERPCTRLTYPE { VDSCRIPTINTERPCTRLTYPE_INVALID = 0, /** Function call to evaluate now, all values are computed * and are stored on the value stack. */ VDSCRIPTINTERPCTRLTYPE_FN_CALL, /** Cleanup the function call, deleting the scope and restoring the previous one. */ VDSCRIPTINTERPCTRLTYPE_FN_CALL_CLEANUP, /** If statement to evaluate now, the guard is on the stack. */ VDSCRIPTINTERPCTRLTYPE_IF, /** While or for statement. */ VDSCRIPTINTERPCTRLTYPE_LOOP, /** switch statement. */ VDSCRIPTINTERPCTRLTYPE_SWITCH, /** Compound statement. */ VDSCRIPTINTERPCTRLTYPE_COMPOUND, /** 32bit blowup. */ VDSCRIPTINTERPCTRLTYPE_32BIT_HACK = 0x7fffffff } VDSCRIPTINTERPCTRLTYPE; /** Pointer to a control type. */ typedef VDSCRIPTINTERPCTRLTYPE *PVDSCRIPTINTERPCTRLTYPE; /** * Interpreter stack control entry. */ typedef struct VDSCRIPTINTERPCTRL { /** Flag whether this entry points to an AST node to evaluate. */ bool fEvalAst; /** Flag dependent data. */ union { /** Pointer to the AST node to interprete. */ PVDSCRIPTASTCORE pAstNode; /** Interpreter control structure. */ struct { /** Type of control. */ VDSCRIPTINTERPCTRLTYPE enmCtrlType; /** Function call data. */ struct { /** Function to call. */ PVDSCRIPTFN pFn; } FnCall; /** Compound statement. */ struct { /** The compound statement node. */ PVDSCRIPTASTSTMT pStmtCompound; /** Current statement evaluated. */ PVDSCRIPTASTSTMT pStmtCurr; } Compound; /** Pointer to an AST node. */ PVDSCRIPTASTCORE pAstNode; } Ctrl; }; } VDSCRIPTINTERPCTRL; /** Pointer to an exec stack control entry. */ typedef VDSCRIPTINTERPCTRL *PVDSCRIPTINTERPCTRL; /** * Record an error while interpreting. * * @returns VBox status code passed. * @param pThis The interpreter context. * @param rc The status code to record. * @param RT_SRC_POS Position in the source code. * @param pszFmt Format string. */ static int vdScriptInterpreterError(PVDSCRIPTINTERPCTX pThis, int rc, RT_SRC_POS_DECL, const char *pszFmt, ...) { RTPrintf(pszFmt); return rc; } /** * Pops the topmost value from the value stack. * * @returns nothing. * @param pThis The interpreter context. * @param pVal Where to store the value. */ DECLINLINE(void) vdScriptInterpreterPopValue(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTARG pVal) { PVDSCRIPTARG pValStack = (PVDSCRIPTARG)vdScriptStackGetUsed(&pThis->StackValues); if (!pValStack) { RT_ZERO(*pVal); AssertPtrReturnVoid(pValStack); } *pVal = *pValStack; vdScriptStackPop(&pThis->StackValues); } /** * Pushes a given value onto the value stack. */ DECLINLINE(int) vdScriptInterpreterPushValue(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTARG pVal) { PVDSCRIPTARG pValStack = (PVDSCRIPTARG)vdScriptStackGetUnused(&pThis->StackValues); if (!pValStack) return vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory pushing a value on the value stack"); *pValStack = *pVal; vdScriptStackPush(&pThis->StackValues); return VINF_SUCCESS; } /** * Pushes an AST node onto the control stack. * * @returns VBox status code. * @param pThis The interpreter context. * @param enmCtrlType The control entry type. */ DECLINLINE(int) vdScriptInterpreterPushAstEntry(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTCORE pAstNode) { PVDSCRIPTINTERPCTRL pCtrl = NULL; pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUnused(&pThis->StackCtrl); if (pCtrl) { pCtrl->fEvalAst = true; pCtrl->pAstNode = pAstNode; vdScriptStackPush(&pThis->StackCtrl); return VINF_SUCCESS; } return vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory adding an entry on the control stack"); } /** * Pushes a control entry without additional data onto the stack. * * @returns VBox status code. * @param pThis The interpreter context. * @param enmCtrlType The control entry type. */ DECLINLINE(int) vdScriptInterpreterPushNonDataCtrlEntry(PVDSCRIPTINTERPCTX pThis, VDSCRIPTINTERPCTRLTYPE enmCtrlType) { PVDSCRIPTINTERPCTRL pCtrl = NULL; pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUnused(&pThis->StackCtrl); if (pCtrl) { pCtrl->fEvalAst = false; pCtrl->Ctrl.enmCtrlType = enmCtrlType; vdScriptStackPush(&pThis->StackCtrl); return VINF_SUCCESS; } return vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory adding an entry on the control stack"); } /** * Pushes a compound statement control entry onto the stack. * * @returns VBox status code. * @param pThis The interpreter context. * @param pStmtFirst The first statement of the compound statement */ DECLINLINE(int) vdScriptInterpreterPushCompoundCtrlEntry(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTSTMT pStmt) { PVDSCRIPTINTERPCTRL pCtrl = NULL; pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUnused(&pThis->StackCtrl); if (pCtrl) { pCtrl->fEvalAst = false; pCtrl->Ctrl.enmCtrlType = VDSCRIPTINTERPCTRLTYPE_COMPOUND; pCtrl->Ctrl.Compound.pStmtCompound = pStmt; pCtrl->Ctrl.Compound.pStmtCurr = RTListGetFirst(&pStmt->Compound.ListStmts, VDSCRIPTASTSTMT, Core.ListNode); vdScriptStackPush(&pThis->StackCtrl); return VINF_SUCCESS; } return vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory adding an entry on the control stack"); } /** * Pushes a while statement control entry onto the stack. * * @returns VBox status code. * @param pThis The interpreter context. * @param pStmt The while statement. */ DECLINLINE(int) vdScriptInterpreterPushWhileCtrlEntry(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTSTMT pStmt) { int rc = VINF_SUCCESS; PVDSCRIPTINTERPCTRL pCtrl = NULL; pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUnused(&pThis->StackCtrl); if (pCtrl) { pCtrl->fEvalAst = false; pCtrl->Ctrl.enmCtrlType = VDSCRIPTINTERPCTRLTYPE_LOOP; pCtrl->Ctrl.pAstNode = &pStmt->Core; vdScriptStackPush(&pThis->StackCtrl); rc = vdScriptInterpreterPushAstEntry(pThis, &pStmt->While.pCond->Core); if ( RT_SUCCESS(rc) && pStmt->While.fDoWhile) { /* Push the statement to execute for do ... while loops because they run at least once. */ rc = vdScriptInterpreterPushAstEntry(pThis, &pStmt->While.pStmt->Core); if (RT_FAILURE(rc)) { /* Cleanup while control statement and AST node. */ vdScriptStackPop(&pThis->StackCtrl); vdScriptStackPop(&pThis->StackCtrl); } } else if (RT_FAILURE(rc)) vdScriptStackPop(&pThis->StackCtrl); /* Cleanup the while control statement. */ } else rc = vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory adding an entry on the control stack"); return rc; } /** * Pushes an if statement control entry onto the stack. * * @returns VBox status code. * @param pThis The interpreter context. * @param pStmt The if statement. */ static int vdScriptInterpreterPushIfCtrlEntry(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTSTMT pStmt) { int rc = VINF_SUCCESS; PVDSCRIPTINTERPCTRL pCtrl = NULL; pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUnused(&pThis->StackCtrl); if (pCtrl) { pCtrl->fEvalAst = false; pCtrl->Ctrl.enmCtrlType = VDSCRIPTINTERPCTRLTYPE_IF; pCtrl->Ctrl.pAstNode = &pStmt->Core; vdScriptStackPush(&pThis->StackCtrl); rc = vdScriptInterpreterPushAstEntry(pThis, &pStmt->If.pCond->Core); } else rc = vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory adding an entry on the control stack"); return rc; } /** * Pushes a for statement control entry onto the stack. * * @returns VBox status code. * @param pThis The interpreter context. * @param pStmt The while statement. */ DECLINLINE(int) vdScriptInterpreterPushForCtrlEntry(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTSTMT pStmt) { int rc = VINF_SUCCESS; PVDSCRIPTINTERPCTRL pCtrl = NULL; pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUnused(&pThis->StackCtrl); if (pCtrl) { pCtrl->fEvalAst = false; pCtrl->Ctrl.enmCtrlType = VDSCRIPTINTERPCTRLTYPE_LOOP; pCtrl->Ctrl.pAstNode = &pStmt->Core; vdScriptStackPush(&pThis->StackCtrl); /* Push the conditional first and the the initializer .*/ rc = vdScriptInterpreterPushAstEntry(pThis, &pStmt->For.pExprCond->Core); if (RT_SUCCESS(rc)) { rc = vdScriptInterpreterPushAstEntry(pThis, &pStmt->For.pExprStart->Core); if (RT_FAILURE(rc)) vdScriptStackPop(&pThis->StackCtrl); } } else rc = vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory adding an entry on the control stack"); return rc; } /** * Destroy variable string space callback. */ static DECLCALLBACK(int) vdScriptInterpreterVarSpaceDestroy(PRTSTRSPACECORE pStr, void *pvUser) { RTMemFree(pStr); return VINF_SUCCESS; } /** * Setsup a new scope in the current function call. * * @returns VBox status code. * @param pThis The interpreter context. */ static int vdScriptInterpreterScopeCreate(PVDSCRIPTINTERPCTX pThis) { int rc = VINF_SUCCESS; PVDSCRIPTINTERPSCOPE pScope = (PVDSCRIPTINTERPSCOPE)RTMemAllocZ(sizeof(VDSCRIPTINTERPSCOPE)); if (pScope) { pScope->pParent = pThis->pFnCallCurr->pScopeCurr; pScope->hStrSpaceVar = NULL; pThis->pFnCallCurr->pScopeCurr = pScope; } else rc = vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory allocating new scope"); return rc; } /** * Destroys the current scope. * * @returns nothing. * @param pThis The interpreter context. */ static void vdScriptInterpreterScopeDestroyCurr(PVDSCRIPTINTERPCTX pThis) { AssertMsgReturnVoid(pThis->pFnCallCurr->pScopeCurr != &pThis->pFnCallCurr->ScopeRoot, ("Current scope is root scope of function call\n")); PVDSCRIPTINTERPSCOPE pScope = pThis->pFnCallCurr->pScopeCurr; pThis->pFnCallCurr->pScopeCurr = pScope->pParent; RTStrSpaceDestroy(&pScope->hStrSpaceVar, vdScriptInterpreterVarSpaceDestroy, NULL); RTMemFree(pScope); } /** * Get the content of the given variable identifier from the current or parent scope. */ static PVDSCRIPTINTERPVAR vdScriptInterpreterGetVar(PVDSCRIPTINTERPCTX pThis, const char *pszVar) { PVDSCRIPTINTERPSCOPE pScopeCurr = pThis->pFnCallCurr->pScopeCurr; PVDSCRIPTINTERPVAR pVar = NULL; while ( !pVar && pScopeCurr) { pVar = (PVDSCRIPTINTERPVAR)RTStrSpaceGet(&pScopeCurr->hStrSpaceVar, pszVar); if (pVar) break; pScopeCurr = pScopeCurr->pParent; } return pVar; } /** * Evaluate an expression. * * @returns VBox status code. * @param pThis The interpreter context. * @param pExpr The expression to evaluate. */ static int vdScriptInterpreterEvaluateExpression(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTEXPR pExpr) { int rc = VINF_SUCCESS; switch (pExpr->enmType) { case VDSCRIPTEXPRTYPE_PRIMARY_NUMCONST: { /* Push the numerical constant on the value stack. */ VDSCRIPTARG NumConst; NumConst.enmType = VDSCRIPTTYPE_UINT64; NumConst.u64 = pExpr->u64; rc = vdScriptInterpreterPushValue(pThis, &NumConst); break; } case VDSCRIPTEXPRTYPE_PRIMARY_STRINGCONST: { /* Push the string literal on the value stack. */ VDSCRIPTARG StringConst; StringConst.enmType = VDSCRIPTTYPE_STRING; StringConst.psz = pExpr->pszStr; rc = vdScriptInterpreterPushValue(pThis, &StringConst); break; } case VDSCRIPTEXPRTYPE_PRIMARY_BOOLEAN: { VDSCRIPTARG BoolConst; BoolConst.enmType = VDSCRIPTTYPE_BOOL; BoolConst.f = pExpr->f; rc = vdScriptInterpreterPushValue(pThis, &BoolConst); break; } case VDSCRIPTEXPRTYPE_PRIMARY_IDENTIFIER: { /* Look it up and push the value onto the value stack. */ PVDSCRIPTINTERPVAR pVar = vdScriptInterpreterGetVar(pThis, pExpr->pIde->aszIde); AssertPtrReturn(pVar, VERR_IPE_UNINITIALIZED_STATUS); rc = vdScriptInterpreterPushValue(pThis, &pVar->Value); break; } case VDSCRIPTEXPRTYPE_POSTFIX_INCREMENT: case VDSCRIPTEXPRTYPE_POSTFIX_DECREMENT: AssertMsgFailed(("TODO\n")); case VDSCRIPTEXPRTYPE_POSTFIX_FNCALL: { PVDSCRIPTFN pFn = (PVDSCRIPTFN)RTStrSpaceGet(&pThis->pScriptCtx->hStrSpaceFn, pExpr->FnCall.pFnIde->pIde->aszIde); if (pFn) { /* Push a function call control entry on the stack. */ PVDSCRIPTINTERPCTRL pCtrlFn = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUnused(&pThis->StackCtrl); if (pCtrlFn) { pCtrlFn->fEvalAst = false; pCtrlFn->Ctrl.enmCtrlType = VDSCRIPTINTERPCTRLTYPE_FN_CALL; pCtrlFn->Ctrl.FnCall.pFn = pFn; vdScriptStackPush(&pThis->StackCtrl); /* Push parameter expressions on the stack. */ PVDSCRIPTASTEXPR pArg = RTListGetFirst(&pExpr->FnCall.ListArgs, VDSCRIPTASTEXPR, Core.ListNode); while (pArg) { rc = vdScriptInterpreterPushAstEntry(pThis, &pArg->Core); if (RT_FAILURE(rc)) break; pArg = RTListGetNext(&pExpr->FnCall.ListArgs, pArg, VDSCRIPTASTEXPR, Core.ListNode); } } } else AssertMsgFailed(("Invalid program given, unknown function: %s\n", pExpr->FnCall.pFnIde->pIde->aszIde)); break; } case VDSCRIPTEXPRTYPE_UNARY_INCREMENT: case VDSCRIPTEXPRTYPE_UNARY_DECREMENT: case VDSCRIPTEXPRTYPE_UNARY_POSSIGN: case VDSCRIPTEXPRTYPE_UNARY_NEGSIGN: case VDSCRIPTEXPRTYPE_UNARY_INVERT: case VDSCRIPTEXPRTYPE_UNARY_NEGATE: case VDSCRIPTEXPRTYPE_MULTIPLICATION: case VDSCRIPTEXPRTYPE_DIVISION: case VDSCRIPTEXPRTYPE_MODULUS: case VDSCRIPTEXPRTYPE_ADDITION: case VDSCRIPTEXPRTYPE_SUBTRACTION: case VDSCRIPTEXPRTYPE_LSR: case VDSCRIPTEXPRTYPE_LSL: case VDSCRIPTEXPRTYPE_LOWER: case VDSCRIPTEXPRTYPE_HIGHER: case VDSCRIPTEXPRTYPE_LOWEREQUAL: case VDSCRIPTEXPRTYPE_HIGHEREQUAL: case VDSCRIPTEXPRTYPE_EQUAL: case VDSCRIPTEXPRTYPE_NOTEQUAL: case VDSCRIPTEXPRTYPE_BITWISE_AND: case VDSCRIPTEXPRTYPE_BITWISE_XOR: case VDSCRIPTEXPRTYPE_BITWISE_OR: case VDSCRIPTEXPRTYPE_LOGICAL_AND: case VDSCRIPTEXPRTYPE_LOGICAL_OR: case VDSCRIPTEXPRTYPE_ASSIGN: case VDSCRIPTEXPRTYPE_ASSIGN_MULT: case VDSCRIPTEXPRTYPE_ASSIGN_DIV: case VDSCRIPTEXPRTYPE_ASSIGN_MOD: case VDSCRIPTEXPRTYPE_ASSIGN_ADD: case VDSCRIPTEXPRTYPE_ASSIGN_SUB: case VDSCRIPTEXPRTYPE_ASSIGN_LSL: case VDSCRIPTEXPRTYPE_ASSIGN_LSR: case VDSCRIPTEXPRTYPE_ASSIGN_AND: case VDSCRIPTEXPRTYPE_ASSIGN_XOR: case VDSCRIPTEXPRTYPE_ASSIGN_OR: case VDSCRIPTEXPRTYPE_ASSIGNMENT_LIST: AssertMsgFailed(("TODO\n")); default: AssertMsgFailed(("Invalid expression type: %d\n", pExpr->enmType)); } return rc; } /** * Evaluate a statement. * * @returns VBox status code. * @param pThis The interpreter context. * @param pStmt The statement to evaluate. */ static int vdScriptInterpreterEvaluateStatement(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTSTMT pStmt) { int rc = VINF_SUCCESS; switch (pStmt->enmStmtType) { case VDSCRIPTSTMTTYPE_COMPOUND: { /* Setup new scope. */ rc = vdScriptInterpreterScopeCreate(pThis); if (RT_SUCCESS(rc)) { /** @todo: Declarations */ rc = vdScriptInterpreterPushCompoundCtrlEntry(pThis, pStmt); } break; } case VDSCRIPTSTMTTYPE_EXPRESSION: { rc = vdScriptInterpreterPushAstEntry(pThis, &pStmt->pExpr->Core); break; } case VDSCRIPTSTMTTYPE_IF: { rc = vdScriptInterpreterPushIfCtrlEntry(pThis, pStmt); break; } case VDSCRIPTSTMTTYPE_SWITCH: AssertMsgFailed(("TODO\n")); break; case VDSCRIPTSTMTTYPE_WHILE: { rc = vdScriptInterpreterPushWhileCtrlEntry(pThis, pStmt); break; } case VDSCRIPTSTMTTYPE_RETURN: { /* Walk up the control stack until we reach a function cleanup entry. */ PVDSCRIPTINTERPCTRL pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); while ( pCtrl && ( pCtrl->fEvalAst || pCtrl->Ctrl.enmCtrlType != VDSCRIPTINTERPCTRLTYPE_FN_CALL_CLEANUP)) { /* Cleanup up any compound statement scope. */ if ( !pCtrl->fEvalAst && pCtrl->Ctrl.enmCtrlType == VDSCRIPTINTERPCTRLTYPE_COMPOUND) vdScriptInterpreterScopeDestroyCurr(pThis); vdScriptStackPop(&pThis->StackCtrl); pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); } AssertMsg(VALID_PTR(pCtrl), ("Incorrect program, return outside of function\n")); break; } case VDSCRIPTSTMTTYPE_FOR: { rc = vdScriptInterpreterPushForCtrlEntry(pThis, pStmt); break; } case VDSCRIPTSTMTTYPE_CONTINUE: { /* Remove everything up to a loop control entry. */ PVDSCRIPTINTERPCTRL pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); while ( pCtrl && ( pCtrl->fEvalAst || pCtrl->Ctrl.enmCtrlType != VDSCRIPTINTERPCTRLTYPE_LOOP)) { /* Cleanup up any compound statement scope. */ if ( !pCtrl->fEvalAst && pCtrl->Ctrl.enmCtrlType == VDSCRIPTINTERPCTRLTYPE_COMPOUND) vdScriptInterpreterScopeDestroyCurr(pThis); vdScriptStackPop(&pThis->StackCtrl); pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); } AssertMsg(VALID_PTR(pCtrl), ("Incorrect program, continue outside of loop\n")); /* Put the conditionals for while and for loops onto the control stack again. */ PVDSCRIPTASTSTMT pLoopStmt = (PVDSCRIPTASTSTMT)pCtrl->Ctrl.pAstNode; AssertMsg( pLoopStmt->enmStmtType == VDSCRIPTSTMTTYPE_WHILE || pLoopStmt->enmStmtType == VDSCRIPTSTMTTYPE_FOR, ("Invalid statement type, must be for or while loop\n")); if (pLoopStmt->enmStmtType == VDSCRIPTSTMTTYPE_FOR) rc = vdScriptInterpreterPushAstEntry(pThis, &pLoopStmt->For.pExprCond->Core); else if (!pLoopStmt->While.fDoWhile) rc = vdScriptInterpreterPushAstEntry(pThis, &pLoopStmt->While.pCond->Core); break; } case VDSCRIPTSTMTTYPE_BREAK: { /* Remove everything including the loop control statement. */ PVDSCRIPTINTERPCTRL pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); while ( pCtrl && ( pCtrl->fEvalAst || pCtrl->Ctrl.enmCtrlType != VDSCRIPTINTERPCTRLTYPE_LOOP)) { /* Cleanup up any compound statement scope. */ if ( !pCtrl->fEvalAst && pCtrl->Ctrl.enmCtrlType == VDSCRIPTINTERPCTRLTYPE_COMPOUND) vdScriptInterpreterScopeDestroyCurr(pThis); vdScriptStackPop(&pThis->StackCtrl); pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); } AssertMsg(VALID_PTR(pCtrl), ("Incorrect program, break outside of loop\n")); vdScriptStackPop(&pThis->StackCtrl); /* Remove loop control statement. */ break; } case VDSCRIPTSTMTTYPE_CASE: case VDSCRIPTSTMTTYPE_DEFAULT: AssertMsgFailed(("TODO\n")); break; default: AssertMsgFailed(("Invalid statement type: %d\n", pStmt->enmStmtType)); } return rc; } /** * Evaluates the given AST node. * * @returns VBox statuse code. * @param pThis The interpreter context. * @param pAstNode The AST node to interpret. */ static int vdScriptInterpreterEvaluateAst(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTASTCORE pAstNode) { int rc = VERR_NOT_IMPLEMENTED; switch (pAstNode->enmClass) { case VDSCRIPTASTCLASS_DECLARATION: { AssertMsgFailed(("TODO\n")); break; } case VDSCRIPTASTCLASS_STATEMENT: { rc = vdScriptInterpreterEvaluateStatement(pThis, (PVDSCRIPTASTSTMT)pAstNode); break; } case VDSCRIPTASTCLASS_EXPRESSION: { rc = vdScriptInterpreterEvaluateExpression(pThis, (PVDSCRIPTASTEXPR)pAstNode); break; } /* These should never ever appear here. */ case VDSCRIPTASTCLASS_IDENTIFIER: case VDSCRIPTASTCLASS_FUNCTION: case VDSCRIPTASTCLASS_FUNCTIONARG: case VDSCRIPTASTCLASS_INVALID: default: AssertMsgFailed(("Invalid AST node class: %d\n", pAstNode->enmClass)); } return rc; } /** * Evaluate a function call. * * @returns VBox status code. * @param pThis The interpreter context. * @param pFn The function execute. */ static int vdScriptInterpreterFnCall(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTFN pFn) { int rc = VINF_SUCCESS; if (!pFn->fExternal) { PVDSCRIPTASTFN pAstFn = pFn->Type.Internal.pAstFn; /* Add function call cleanup marker on the stack first. */ rc = vdScriptInterpreterPushNonDataCtrlEntry(pThis, VDSCRIPTINTERPCTRLTYPE_FN_CALL_CLEANUP); if (RT_SUCCESS(rc)) { /* Create function call frame and set it up. */ PVDSCRIPTINTERPFNCALL pFnCall = (PVDSCRIPTINTERPFNCALL)RTMemAllocZ(sizeof(VDSCRIPTINTERPFNCALL)); if (pFnCall) { pFnCall->pCaller = pThis->pFnCallCurr; pFnCall->ScopeRoot.pParent = NULL; pFnCall->ScopeRoot.hStrSpaceVar = NULL; pFnCall->pScopeCurr = &pFnCall->ScopeRoot; /* Add the variables, remember order. The first variable in the argument has the value at the top of the value stack. */ PVDSCRIPTASTFNARG pArg = RTListGetFirst(&pAstFn->ListArgs, VDSCRIPTASTFNARG, Core.ListNode); for (unsigned i = 0; i < pAstFn->cArgs; i++) { PVDSCRIPTINTERPVAR pVar = (PVDSCRIPTINTERPVAR)RTMemAllocZ(sizeof(VDSCRIPTINTERPVAR)); if (pVar) { pVar->Core.pszString = pArg->pArgIde->aszIde; pVar->Core.cchString = pArg->pArgIde->cchIde; vdScriptInterpreterPopValue(pThis, &pVar->Value); bool fInserted = RTStrSpaceInsert(&pFnCall->ScopeRoot.hStrSpaceVar, &pVar->Core); Assert(fInserted); } else { rc = vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory creating a variable"); break; } pArg = RTListGetNext(&pAstFn->ListArgs, pArg, VDSCRIPTASTFNARG, Core.ListNode); } if (RT_SUCCESS(rc)) { /* * Push compount statement on the control stack and make the newly created * call frame the current one. */ rc = vdScriptInterpreterPushAstEntry(pThis, &pAstFn->pCompoundStmts->Core); if (RT_SUCCESS(rc)) pThis->pFnCallCurr = pFnCall; } if (RT_FAILURE(rc)) { RTStrSpaceDestroy(&pFnCall->ScopeRoot.hStrSpaceVar, vdScriptInterpreterVarSpaceDestroy, NULL); RTMemFree(pFnCall); } } else rc = vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory creating a call frame"); } } else { /* External function call, build the argument list. */ if (pFn->cArgs) { PVDSCRIPTARG paArgs = (PVDSCRIPTARG)RTMemAllocZ(pFn->cArgs * sizeof(VDSCRIPTARG)); if (paArgs) { for (unsigned i = 0; i < pFn->cArgs; i++) vdScriptInterpreterPopValue(pThis, &paArgs[i]); rc = pFn->Type.External.pfnCallback(paArgs, pFn->Type.External.pvUser); RTMemFree(paArgs); } else rc = vdScriptInterpreterError(pThis, VERR_NO_MEMORY, RT_SRC_POS, "Out of memory creating argument array for external function call"); } else rc = pFn->Type.External.pfnCallback(NULL, pFn->Type.External.pvUser); } return rc; } /** * Evaluate interpreter control statement. * * @returns VBox status code. * @param pThis The interpreter context. * @param pCtrl The control entry to evaluate. */ static int vdScriptInterpreterEvaluateCtrlEntry(PVDSCRIPTINTERPCTX pThis, PVDSCRIPTINTERPCTRL pCtrl) { int rc = VINF_SUCCESS; Assert(!pCtrl->fEvalAst); switch (pCtrl->Ctrl.enmCtrlType) { case VDSCRIPTINTERPCTRLTYPE_FN_CALL: { PVDSCRIPTFN pFn = pCtrl->Ctrl.FnCall.pFn; vdScriptStackPop(&pThis->StackCtrl); rc = vdScriptInterpreterFnCall(pThis, pFn); break; } case VDSCRIPTINTERPCTRLTYPE_FN_CALL_CLEANUP: { vdScriptStackPop(&pThis->StackCtrl); /* Delete function call entry. */ AssertPtr(pThis->pFnCallCurr); PVDSCRIPTINTERPFNCALL pFnCallFree = pThis->pFnCallCurr; pThis->pFnCallCurr = pFnCallFree->pCaller; Assert(pFnCallFree->pScopeCurr == &pFnCallFree->ScopeRoot); RTStrSpaceDestroy(&pFnCallFree->ScopeRoot.hStrSpaceVar, vdScriptInterpreterVarSpaceDestroy, NULL); RTMemFree(pFnCallFree); break; } case VDSCRIPTINTERPCTRLTYPE_COMPOUND: { if (!pCtrl->Ctrl.Compound.pStmtCurr) { /* Evaluated last statement, cleanup and remove the control statement from the stack. */ vdScriptInterpreterScopeDestroyCurr(pThis); vdScriptStackPop(&pThis->StackCtrl); } else { /* Push the current statement onto the control stack and move on. */ rc = vdScriptInterpreterPushAstEntry(pThis, &pCtrl->Ctrl.Compound.pStmtCurr->Core); if (RT_SUCCESS(rc)) { pCtrl->Ctrl.Compound.pStmtCurr = RTListGetNext(&pCtrl->Ctrl.Compound.pStmtCompound->Compound.ListStmts, pCtrl->Ctrl.Compound.pStmtCurr, VDSCRIPTASTSTMT, Core.ListNode); } } break; } case VDSCRIPTINTERPCTRLTYPE_LOOP: { PVDSCRIPTASTSTMT pLoopStmt = (PVDSCRIPTASTSTMT)pCtrl->Ctrl.pAstNode; /* Check whether the condition passed. */ VDSCRIPTARG Cond; vdScriptInterpreterPopValue(pThis, &Cond); AssertMsg(Cond.enmType == VDSCRIPTTYPE_BOOL, ("Value on stack is not of boolean type\n")); if (Cond.f) { /* Execute the loop another round. */ if (pLoopStmt->enmStmtType == VDSCRIPTSTMTTYPE_WHILE) { rc = vdScriptInterpreterPushAstEntry(pThis, &pLoopStmt->While.pCond->Core); if (RT_SUCCESS(rc)) { rc = vdScriptInterpreterPushAstEntry(pThis, &pLoopStmt->While.pStmt->Core); if (RT_FAILURE(rc)) vdScriptStackPop(&pThis->StackCtrl); } } else { AssertMsg(pLoopStmt->enmStmtType == VDSCRIPTSTMTTYPE_FOR, ("Not a for statement\n")); rc = vdScriptInterpreterPushAstEntry(pThis, &pLoopStmt->For.pExprCond->Core); if (RT_SUCCESS(rc)) { rc = vdScriptInterpreterPushAstEntry(pThis, &pLoopStmt->For.pExpr3->Core); if (RT_SUCCESS(rc)) { rc = vdScriptInterpreterPushAstEntry(pThis, &pLoopStmt->For.pStmt->Core); if (RT_FAILURE(rc)) vdScriptStackPop(&pThis->StackCtrl); } if (RT_FAILURE(rc)) vdScriptStackPop(&pThis->StackCtrl); } } } else vdScriptStackPop(&pThis->StackCtrl); /* Remove loop control statement. */ break; } case VDSCRIPTINTERPCTRLTYPE_IF: { PVDSCRIPTASTSTMT pIfStmt = (PVDSCRIPTASTSTMT)pCtrl->Ctrl.pAstNode; vdScriptStackPop(&pThis->StackCtrl); /* Remove if control statement. */ /* Check whether the condition passed. */ VDSCRIPTARG Cond; vdScriptInterpreterPopValue(pThis, &Cond); AssertMsg(Cond.enmType == VDSCRIPTTYPE_BOOL, ("Value on stack is not of boolean type\n")); if (Cond.f) { /* Execute the true branch. */ rc = vdScriptInterpreterPushAstEntry(pThis, &pIfStmt->If.pTrueStmt->Core); } else if (pIfStmt->If.pElseStmt) rc = vdScriptInterpreterPushAstEntry(pThis, &pIfStmt->If.pElseStmt->Core); break; } default: AssertMsgFailed(("Invalid evaluation control type on the stack: %d\n", pCtrl->Ctrl.enmCtrlType)); } return rc; } /** * The interpreter evaluation core loop. * * @returns VBox status code. * @param pThis The interpreter context. */ static int vdScriptInterpreterEvaluate(PVDSCRIPTINTERPCTX pThis) { int rc = VINF_SUCCESS; PVDSCRIPTINTERPCTRL pCtrl = NULL; pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); while (pCtrl) { if (pCtrl->fEvalAst) { PVDSCRIPTASTCORE pAstNode = pCtrl->pAstNode; vdScriptStackPop(&pThis->StackCtrl); rc = vdScriptInterpreterEvaluateAst(pThis, pAstNode); } else rc = vdScriptInterpreterEvaluateCtrlEntry(pThis, pCtrl); pCtrl = (PVDSCRIPTINTERPCTRL)vdScriptStackGetUsed(&pThis->StackCtrl); } return rc; } DECLHIDDEN(int) vdScriptCtxInterprete(PVDSCRIPTCTXINT pThis, const char *pszFn, PVDSCRIPTARG paArgs, unsigned cArgs, PVDSCRIPTARG pRet) { int rc = VINF_SUCCESS; VDSCRIPTINTERPCTX InterpCtx; PVDSCRIPTFN pFn = NULL; AssertPtrReturn(pThis, VERR_INVALID_POINTER); AssertPtrReturn(pszFn, VERR_INVALID_POINTER); AssertReturn( (!cArgs && !paArgs) || (cArgs && paArgs), VERR_INVALID_PARAMETER); InterpCtx.pScriptCtx = pThis; InterpCtx.pFnCallCurr = NULL; vdScriptStackInit(&InterpCtx.StackValues, sizeof(VDSCRIPTARG)); vdScriptStackInit(&InterpCtx.StackCtrl, sizeof(VDSCRIPTINTERPCTRL)); pFn = (PVDSCRIPTFN)RTStrSpaceGet(&pThis->hStrSpaceFn, pszFn); if (pFn) { if (cArgs == pFn->cArgs) { /* Push the arguments onto the stack. */ /** @todo: Check expected and given argument types. */ for (unsigned i = 0; i < cArgs; i++) { PVDSCRIPTARG pArg = (PVDSCRIPTARG)vdScriptStackGetUnused(&InterpCtx.StackValues); *pArg = paArgs[i]; vdScriptStackPush(&InterpCtx.StackValues); } if (RT_SUCCESS(rc)) { /* Setup function call frame and parameters. */ rc = vdScriptInterpreterFnCall(&InterpCtx, pFn); if (RT_SUCCESS(rc)) { /* Run the interpreter. */ rc = vdScriptInterpreterEvaluate(&InterpCtx); vdScriptStackDestroy(&InterpCtx.StackValues); vdScriptStackDestroy(&InterpCtx.StackCtrl); } } } else rc = vdScriptInterpreterError(&InterpCtx, VERR_INVALID_PARAMETER, RT_SRC_POS, "Invalid number of parameters, expected %d got %d", pFn->cArgs, cArgs); } else rc = vdScriptInterpreterError(&InterpCtx, VERR_NOT_FOUND, RT_SRC_POS, "Function with identifier \"%s\" not found", pszFn); return rc; }