/*
* Copyright (C) 2015 Andrei Karas
*
* This file is part of Paranoid null checker.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
#include "analysis/statement.h"
#include "command.h"
#include "logger.h"
#include "analysis/analysis.h"
#include "analysis/collections.h"
#include "analysis/reports.h"
#include "analysis/walkitem.h"
#include "nodes/expr/eq_expr.h"
#include "nodes/expr/modify_expr.h"
#include "nodes/expr/ne_expr.h"
#include "nodes/expr/pointerplus_expr.h"
#include "nodes/ref/indirect_ref.h"
#include "nodes/stmt/break_stmt.h"
#include "nodes/stmt/continue_stmt.h"
#include "nodes/stmt/if_stmt.h"
#include "nodes/stmt/while_stmt.h"
#include
#include "localconsts.h"
namespace Analysis
{
void analyseCondition(Node *node,
Node *condNode,
Node *thenNode,
Node *elseNode,
const WalkItem &wi,
WalkItem &wo)
{
condNode = skipNop(condNode);
thenNode = skipNop(thenNode);
elseNode = skipNop(elseNode);
Node *const parent = skipBackNop(node->parent);
bool report(true);
if (parent == INIT_EXPR && parent->parent)
{
if (skipBackNop(parent->parent) == RETURN_EXPR)
{
report = false;
}
}
WalkItem wci = wi;
WalkItem wco = wo;
WalkItem wo2 = wo;
WalkItem wo3 = wo;
walkTree(condNode, wci, wco);
Log::dumpWI(node, "wco ", wco);
WalkItem wi2 = wi;
if (wco.cleanExpr)
removeNeedCheckNullVarsSetAll(wi2, wco.checkedThenNonNullVars);
wi2.needCheckNullVars.insert(wco.checkedThenNullVars.begin(),
wco.checkedThenNullVars.end());
addKnownNullVarsWithLinked(wi2, wco, wco.checkedThenNullVars);
addKnownNonNullVarsWithLinked(wi2, wco, wco.checkedThenNonNullVars);
wi2.needCheckNullVars = wi2.knownVars;
removeNeedCheckNullVarsSetAll(wi2, wi2.knownNonNullVars);
wo2 = wi2;
Log::dumpWI(node, "wi2 then ", wi2);
if (report)
{
reportParmDeclNullPointer(node,
thenNode,
wi2);
}
reportParmDeclLeftNullPointer(node, thenNode, wi2);
walkTree(thenNode, wi2, wo2);
Log::dumpWI(node, "wo2 then ", wo2);
WalkItem wi3 = wi;
if (wco.cleanExpr)
removeNeedCheckNullVarsSetAll(wi3, wco.checkedElseNullVars);
wi3.needCheckNullVars.insert(wco.checkedElseNonNullVars.begin(),
wco.checkedElseNonNullVars.end());
addKnownNullVarsWithLinked(wi3, wco, wco.checkedElseNullVars);
addKnownNonNullVarsWithLinked(wi3, wco, wco.checkedElseNonNullVars);
wi3.needCheckNullVars = wi3.knownVars;
removeNeedCheckNullVarsSetAll(wi3, wi3.knownNonNullVars);
wo3 = wi3;
Log::dumpWI(node, "wi3 else ", wi3);
if (report)
{
reportParmDeclNullPointer(node,
elseNode,
wi3);
}
reportParmDeclLeftNullPointer(node, elseNode, wi3);
walkTree(elseNode, wi3, wo3);
Log::dumpWI(node, "wo3 else ", wo3);
// probably condition wrong
if (wo2.cleanExpr)
mergeElseNullChecked(wo, wo2);
// probably condition wrong
if (wo3.cleanExpr)
mergeElseNullChecked(wo, wo3);
// need check for cleanExpr?
intersectElseNonNullChecked(wo, wo2, wo3);
if (wo2.isReturned || wo2.isContinued)
{
// add variable for ignore for all parent nodes except special like IF_STMT
FOR_EACH (it, wco.checkedElseNonNullVars)
{
wo.removeNullVarsAll.insert(it);
removeNeedCheckNullVar(wo, it);
}
addKnownNonNullVarsWithLinked(wo, wco, wco.checkedElseNonNullVars);
if (wco.cleanExpr)
{
addKnownNullVarsWithLinked(wo, wco, wco.checkedElseNullVars);
}
}
else if (thenNode)
{
addNeedCheckNullVars2(wo2, wo);
removeNeedCheckNullVarsThen(wco, wo2, wo);
removeKnownNullVars2(wo2, wo);
}
if (wo3.isReturned || wo3.isContinued)
{
// add variable for ignore for all parent nodes except special like IF_STMT
FOR_EACH (it, wco.checkedThenNonNullVars)
{
wo.removeNullVarsAll.insert(it);
removeNeedCheckNullVar(wo, it);
}
addKnownNonNullVarsWithLinked(wo, wco, wco.checkedThenNonNullVars);
if (wco.cleanExpr)
{
addKnownNullVarsWithLinked(wo, wco, wco.checkedThenNullVars);
}
}
else if (elseNode)
{
addNeedCheckNullVars2(wo3, wo);
removeNeedCheckNullVarsElse(wco, wo3, wo);
removeKnownNullVars2(wo3, wo);
}
if ((wo2.isReturned || wo2.isContinued) && (wo3.isReturned || wo3.isContinued))
{ // all branches returned or breaked
// add variable for ignore for all parent nodes except special like IF_STMT
FOR_EACH (it, wo.knownVars)
{
wo.removeNullVarsAll.insert(it);
wo.knownNullVars.erase(it);
wo.knownNonNullVars.erase(it);
}
}
else if (thenNode && elseNode)
{ // non branches returned or breaked
FOR_EACH (it, wo2.knownNonNullVars)
{
if (isIn(it, wo3.knownNonNullVars) &&
isNotIn(it, wo.knownNonNullVars))
{ // check if var in both branches known as non null
removeNeedCheckNullVarOnly(wo, it);
addNonNullVar(wo, it);
}
}
FOR_EACH (it, wo2.knownNullVars)
{
if (isIn(it, wo3.knownNullVars) &&
isNotIn(it, wo.knownNullVars))
{
addNullVar(wo, it);
}
}
}
wo.isReturned = false;
wo.isContinued = false;
wo.cleanExpr = true;
wo.stopWalking = true;
wo.uselessExpr = false;
}
void analyseIfStmt(IfStmtNode *node, const WalkItem &wi, WalkItem &wo)
{
// need condition node
if (!node->condition || checkCommand(FindArgs))
return;
analyseCondition(node,
node->condition,
node->thenNode,
node->elseNode,
wi,
wo);
}
void analyseWhileStmt(WhileStmtNode *node, const WalkItem &wi, WalkItem &wo)
{
// need condition node
if (!node->condition || checkCommand(FindArgs))
return;
Node *condNode = skipNop(node->condition);
Node *bodyNode = skipNop(node->body);
if (!condNode)
return;
WalkItem wci = wi;
WalkItem wco = wo;
WalkItem wo2 = wo;
walkTree(condNode, wci, wco);
Log::dumpWI(node, "wco ", wco);
WalkItem wi2 = wi;
if (wco.cleanExpr)
removeNeedCheckNullVarsSetAll(wi2, wco.checkedThenNonNullVars);
addKnownNullVarsWithLinked(wi2, wco, wco.checkedThenNullVars);
addKnownNonNullVarsWithLinked(wi2, wco, wco.checkedThenNonNullVars);
wi2.needCheckNullVars = wi2.knownVars;
enforceNeedCheckNullVars(wi2);
removeNeedCheckNullVarsSetAll(wi2, wi2.knownNonNullVars);
wo2 = wi2;
Log::dumpWI(node, "wi2 body ", wi2);
reportParmDeclNullPointer(node,
bodyNode,
wi2);
walkTree(bodyNode, wi2, wo2);
Log::dumpWI(node, "wo2 body ", wo2);
if (wo2.cleanExpr)
mergeElseNullChecked(wo, wo2);
if (wo2.isReturned || wo2.isContinued)
{
// add variable for ignore for all parent nodes except special like IF_STMT
FOR_EACH (it, wco.checkedElseNonNullVars)
{
wo.removeNullVarsAll.insert(it);
removeNeedCheckNullVar(wo, it);
}
addKnownNonNullVarsWithLinked(wo, wco, wco.checkedElseNonNullVars);
if (wco.cleanExpr)
{
addKnownNullVarsWithLinked(wo, wco, wco.checkedElseNullVars);
}
}
else if (bodyNode)
{
addNeedCheckNullVars2(wo2, wo);
WalkItem wo2Saved = wo2;
WalkItem wcoSaved = wco;
const Command oldCommand = command;
disableCommand(DetectUseless);
// after this wo2 changed for cond node
addNeedCheckNullVars(wo2, wo2);
wci = wo2;
wco = wo2;
walkTree(condNode, wci, wco);
command = oldCommand;
Log::dumpWI(node, "wco2 ", wco);
removeNeedCheckNullVarsThen(wcoSaved, wo2Saved, wo);
removeKnownNullVars2(wo2Saved, wo);
}
wo.isReturned = false;
wo.isContinued = false;
wo.cleanExpr = true;
wo.stopWalking = true;
wo.uselessExpr = false;
}
void analyseContinueStmt(ContinueStmtNode *node, const WalkItem &wi, WalkItem &wo)
{
wo.isContinued = true;
}
void analyseBreakStmt(BreakStmtNode *node, const WalkItem &wi, WalkItem &wo)
{
wo.isContinued = true;
}
}