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path: root/libsolidity/interface/StandardCompiler.cpp
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/*
    This file is part of solidity.

    solidity 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
    (at your option) any later version.

    solidity 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 solidity.  If not, see <http://www.gnu.org/licenses/>.
*/
/**
 * @author Alex Beregszaszi
 * @date 2016
 * Standard JSON compiler interface.
 */

#include <libsolidity/interface/StandardCompiler.h>
#include <liblangutil/SourceReferenceFormatter.h>
#include <libsolidity/ast/ASTJsonConverter.h>
#include <libevmasm/Instruction.h>
#include <libdevcore/JSON.h>
#include <libdevcore/Keccak256.h>

#include <boost/algorithm/string.hpp>

using namespace std;
using namespace dev;
using namespace langutil;
using namespace dev::solidity;

namespace {

Json::Value formatError(
    bool _warning,
    string const& _type,
    string const& _component,
    string const& _message,
    string const& _formattedMessage = "",
    Json::Value const& _sourceLocation = Json::Value()
)
{
    Json::Value error = Json::objectValue;
    error["type"] = _type;
    error["component"] = _component;
    error["severity"] = _warning ? "warning" : "error";
    error["message"] = _message;
    error["formattedMessage"] = (_formattedMessage.length() > 0) ? _formattedMessage : _message;
    if (_sourceLocation.isObject())
        error["sourceLocation"] = _sourceLocation;
    return error;
}

Json::Value formatFatalError(string const& _type, string const& _message)
{
    Json::Value output = Json::objectValue;
    output["errors"] = Json::arrayValue;
    output["errors"].append(formatError(false, _type, "general", _message));
    return output;
}

Json::Value formatErrorWithException(
    Exception const& _exception,
    bool const& _warning,
    string const& _type,
    string const& _component,
    string const& _message,
    function<Scanner const&(string const&)> const& _scannerFromSourceName
)
{
    string message;
    string formattedMessage = SourceReferenceFormatter::formatExceptionInformation(_exception, _type, _scannerFromSourceName);

    // NOTE: the below is partially a copy from SourceReferenceFormatter
    SourceLocation const* location = boost::get_error_info<errinfo_sourceLocation>(_exception);

    if (string const* description = boost::get_error_info<errinfo_comment>(_exception))
        message = ((_message.length() > 0) ? (_message + ":") : "") + *description;
    else
        message = _message;

    Json::Value sourceLocation;
    if (location && location->source && location->source->name() != "")
    {
        sourceLocation["file"] = location->source->name();
        sourceLocation["start"] = location->start;
        sourceLocation["end"] = location->end;
    }

    return formatError(_warning, _type, _component, message, formattedMessage, sourceLocation);
}

set<string> requestedContractNames(Json::Value const& _outputSelection)
{
    set<string> names;
    for (auto const& sourceName: _outputSelection.getMemberNames())
    {
        for (auto const& contractName: _outputSelection[sourceName].getMemberNames())
        {
            /// Consider the "all sources" shortcuts as requesting everything.
            if (contractName == "*" || contractName == "")
                return set<string>();
            names.insert((sourceName == "*" ? "" : sourceName) + ":" + contractName);
        }
    }
    return names;
}

/// Returns true iff @a _hash (hex with 0x prefix) is the Keccak256 hash of the binary data in @a _content.
bool hashMatchesContent(string const& _hash, string const& _content)
{
    try
    {
        return dev::h256(_hash) == dev::keccak256(_content);
    }
    catch (dev::BadHexCharacter const&)
    {
        return false;
    }
}

StringMap createSourceList(Json::Value const& _input)
{
    StringMap sources;
    Json::Value const& jsonSources = _input["sources"];
    if (jsonSources.isObject())
        for (auto const& sourceName: jsonSources.getMemberNames())
            sources[sourceName] = jsonSources[sourceName]["content"].asString();
    return sources;
}

bool isArtifactRequested(Json::Value const& _outputSelection, string const& _artifact)
{
    for (auto const& artifact: _outputSelection)
        /// @TODO support sub-matching, e.g "evm" matches "evm.assembly"
        if (artifact == "*" || artifact == _artifact)
            return true;
    return false;
}

///
/// @a _outputSelection is a JSON object containining a two-level hashmap, where the first level is the filename,
/// the second level is the contract name and the value is an array of artifact names to be requested for that contract.
/// @a _file is the current file
/// @a _contract is the current contract
/// @a _artifact is the current artifact name
///
/// @returns true if the @a _outputSelection has a match for the requested target in the specific file / contract.
///
/// In @a _outputSelection the use of '*' as a wildcard is permitted.
///
/// @TODO optimise this. Perhaps flatten the structure upfront.
///
bool isArtifactRequested(Json::Value const& _outputSelection, string const& _file, string const& _contract, string const& _artifact)
{
    if (!_outputSelection.isObject())
        return false;

    for (auto const& file: { _file, string("*") })
        if (_outputSelection.isMember(file) && _outputSelection[file].isObject())
        {
            /// For SourceUnit-level targets (such as AST) only allow empty name, otherwise
            /// for Contract-level targets try both contract name and wildcard
            vector<string> contracts{ _contract };
            if (!_contract.empty())
                contracts.push_back("*");
            for (auto const& contract: contracts)
                if (
                    _outputSelection[file].isMember(contract) &&
                    _outputSelection[file][contract].isArray() &&
                    isArtifactRequested(_outputSelection[file][contract], _artifact)
                )
                    return true;
        }

    return false;
}

bool isArtifactRequested(Json::Value const& _outputSelection, string const& _file, string const& _contract, vector<string> const& _artifacts)
{
    for (auto const& artifact: _artifacts)
        if (isArtifactRequested(_outputSelection, _file, _contract, artifact))
            return true;
    return false;
}

Json::Value formatLinkReferences(std::map<size_t, std::string> const& linkReferences)
{
    Json::Value ret(Json::objectValue);

    for (auto const& ref: linkReferences)
    {
        string const& fullname = ref.second;
        size_t colon = fullname.rfind(':');
        solAssert(colon != string::npos, "");
        string file = fullname.substr(0, colon);
        string name = fullname.substr(colon + 1);

        Json::Value fileObject = ret.get(file, Json::objectValue);
        Json::Value libraryArray = fileObject.get(name, Json::arrayValue);

        Json::Value entry = Json::objectValue;
        entry["start"] = Json::UInt(ref.first);
        entry["length"] = 20;

        libraryArray.append(entry);
        fileObject[name] = libraryArray;
        ret[file] = fileObject;
    }

    return ret;
}

Json::Value collectEVMObject(eth::LinkerObject const& _object, string const* _sourceMap)
{
    Json::Value output = Json::objectValue;
    output["object"] = _object.toHex();
    output["opcodes"] = solidity::disassemble(_object.bytecode);
    output["sourceMap"] = _sourceMap ? *_sourceMap : "";
    output["linkReferences"] = formatLinkReferences(_object.linkReferences);
    return output;
}

}

Json::Value StandardCompiler::compileInternal(Json::Value const& _input)
{
    m_compilerStack.reset(false);

    if (!_input.isObject())
        return formatFatalError("JSONError", "Input is not a JSON object.");

    if (_input["language"] != "Solidity")
        return formatFatalError("JSONError", "Only \"Solidity\" is supported as a language.");

    Json::Value const& sources = _input["sources"];

    if (!sources.isObject() && !sources.isNull())
        return formatFatalError("JSONError", "\"sources\" is not a JSON object.");

    if (sources.empty())
        return formatFatalError("JSONError", "No input sources specified.");

    Json::Value errors = Json::arrayValue;

    for (auto const& sourceName: sources.getMemberNames())
    {
        string hash;

        if (!sources[sourceName].isObject())
            return formatFatalError("JSONError", "Source input is not a JSON object.");

        if (sources[sourceName]["keccak256"].isString())
            hash = sources[sourceName]["keccak256"].asString();

        if (sources[sourceName]["content"].isString())
        {
            string content = sources[sourceName]["content"].asString();
            if (!hash.empty() && !hashMatchesContent(hash, content))
                errors.append(formatError(
                    false,
                    "IOError",
                    "general",
                    "Mismatch between content and supplied hash for \"" + sourceName + "\""
                ));
            else
                m_compilerStack.addSource(sourceName, content);
        }
        else if (sources[sourceName]["urls"].isArray())
        {
            if (!m_readFile)
                return formatFatalError("JSONError", "No import callback supplied, but URL is requested.");

            bool found = false;
            vector<string> failures;

            for (auto const& url: sources[sourceName]["urls"])
            {
                if (!url.isString())
                    return formatFatalError("JSONError", "URL must be a string.");
                ReadCallback::Result result = m_readFile(url.asString());
                if (result.success)
                {
                    if (!hash.empty() && !hashMatchesContent(hash, result.responseOrErrorMessage))
                        errors.append(formatError(
                            false,
                            "IOError",
                            "general",
                            "Mismatch between content and supplied hash for \"" + sourceName + "\" at \"" + url.asString() + "\""
                        ));
                    else
                    {
                        m_compilerStack.addSource(sourceName, result.responseOrErrorMessage);
                        found = true;
                        break;
                    }
                }
                else
                    failures.push_back("Cannot import url (\"" + url.asString() + "\"): " + result.responseOrErrorMessage);
            }

            for (auto const& failure: failures)
            {
                /// If the import succeeded, let mark all the others as warnings, otherwise all of them are errors.
                errors.append(formatError(
                    found ? true : false,
                    "IOError",
                    "general",
                    failure
                ));
            }
        }
        else
            return formatFatalError("JSONError", "Invalid input source specified.");
    }

    Json::Value const& auxInputs = _input["auxiliaryInput"];
    if (!!auxInputs)
    {
        Json::Value const& smtlib2Responses = auxInputs["smtlib2responses"];
        if (!!smtlib2Responses)
            for (auto const& hashString: smtlib2Responses.getMemberNames())
            {
                h256 hash;
                try
                {
                    hash = h256(hashString);
                }
                catch (dev::BadHexCharacter const&)
                {
                    return formatFatalError("JSONError", "Invalid hex encoding of SMTLib2 auxiliary input.");
                }

                m_compilerStack.addSMTLib2Response(hash, smtlib2Responses[hashString].asString());
            }
    }

    Json::Value const& settings = _input.get("settings", Json::Value());

    if (settings.isMember("evmVersion"))
    {
        if (!settings["evmVersion"].isString())
            return formatFatalError("JSONError", "evmVersion must be a string.");
        boost::optional<EVMVersion> version = EVMVersion::fromString(settings["evmVersion"].asString());
        if (!version)
            return formatFatalError("JSONError", "Invalid EVM version requested.");
        m_compilerStack.setEVMVersion(*version);
    }

    vector<CompilerStack::Remapping> remappings;
    for (auto const& remapping: settings.get("remappings", Json::Value()))
    {
        if (!remapping.isString())
            return formatFatalError("JSONError", "Remapping entry must be a string.");
        if (auto r = CompilerStack::parseRemapping(remapping.asString()))
            remappings.emplace_back(std::move(*r));
        else
            return formatFatalError("JSONError", "Invalid remapping: \"" + remapping.asString() + "\"");
    }
    m_compilerStack.setRemappings(remappings);

    if (settings.isMember("optimizer"))
    {
        Json::Value optimizerSettings = settings["optimizer"];
        if (optimizerSettings.isMember("enabled"))
        {
            if (!optimizerSettings["enabled"].isBool())
                return formatFatalError("JSONError", "The \"enabled\" setting must be a boolean.");

            bool const optimize = optimizerSettings["enabled"].asBool();
            unsigned optimizeRuns = 200;
            if (optimizerSettings.isMember("runs"))
            {
                if (!optimizerSettings["runs"].isUInt())
                    return formatFatalError("JSONError", "The \"runs\" setting must be an unsigned number.");
                optimizeRuns = optimizerSettings["runs"].asUInt();
            }
            m_compilerStack.setOptimiserSettings(optimize, optimizeRuns);
        }
    }

    map<string, h160> libraries;
    Json::Value jsonLibraries = settings.get("libraries", Json::Value(Json::objectValue));
    if (!jsonLibraries.isObject())
        return formatFatalError("JSONError", "\"libraries\" is not a JSON object.");
    for (auto const& sourceName: jsonLibraries.getMemberNames())
    {
        auto const& jsonSourceName = jsonLibraries[sourceName];
        if (!jsonSourceName.isObject())
            return formatFatalError("JSONError", "Library entry is not a JSON object.");
        for (auto const& library: jsonSourceName.getMemberNames())
        {
            if (!jsonSourceName[library].isString())
                return formatFatalError("JSONError", "Library address must be a string.");
            string address = jsonSourceName[library].asString();

            if (!boost::starts_with(address, "0x"))
                return formatFatalError(
                    "JSONError",
                    "Library address is not prefixed with \"0x\"."
                );

            if (address.length() != 42)
                return formatFatalError(
                    "JSONError",
                    "Library address is of invalid length."
                );

            try
            {
                // @TODO use libraries only for the given source
                libraries[library] = h160(address);
            }
            catch (dev::BadHexCharacter const&)
            {
                return formatFatalError(
                    "JSONError",
                    "Invalid library address (\"" + address + "\") supplied."
                );
            }
        }
    }
    m_compilerStack.setLibraries(libraries);

    Json::Value metadataSettings = settings.get("metadata", Json::Value());
    m_compilerStack.useMetadataLiteralSources(metadataSettings.get("useLiteralContent", Json::Value(false)).asBool());

    Json::Value outputSelection = settings.get("outputSelection", Json::Value());
    m_compilerStack.setRequestedContractNames(requestedContractNames(outputSelection));

    auto scannerFromSourceName = [&](string const& _sourceName) -> Scanner const& { return m_compilerStack.scanner(_sourceName); };

    try
    {
        m_compilerStack.compile();

        for (auto const& error: m_compilerStack.errors())
        {
            Error const& err = dynamic_cast<Error const&>(*error);

            errors.append(formatErrorWithException(
                *error,
                err.type() == Error::Type::Warning,
                err.typeName(),
                "general",
                "",
                scannerFromSourceName
            ));
        }
    }
    /// This is only thrown in a very few locations.
    catch (Error const& _error)
    {
        errors.append(formatErrorWithException(
            _error,
            false,
            _error.typeName(),
            "general",
            "Uncaught error: ",
            scannerFromSourceName
        ));
    }
    /// This should not be leaked from compile().
    catch (FatalError const& _exception)
    {
        errors.append(formatError(
            false,
            "FatalError",
            "general",
            "Uncaught fatal error: " + boost::diagnostic_information(_exception)
        ));
    }
    catch (CompilerError const& _exception)
    {
        errors.append(formatErrorWithException(
            _exception,
            false,
            "CompilerError",
            "general",
            "Compiler error (" + _exception.lineInfo() + ")",
            scannerFromSourceName
        ));
    }
    catch (InternalCompilerError const& _exception)
    {
        errors.append(formatErrorWithException(
            _exception,
            false,
            "InternalCompilerError",
            "general",
            "Internal compiler error (" + _exception.lineInfo() + ")",
            scannerFromSourceName
        ));
    }
    catch (UnimplementedFeatureError const& _exception)
    {
        errors.append(formatErrorWithException(
            _exception,
            false,
            "UnimplementedFeatureError",
            "general",
            "Unimplemented feature (" + _exception.lineInfo() + ")",
            scannerFromSourceName
        ));
    }
    catch (Exception const& _exception)
    {
        errors.append(formatError(
            false,
            "Exception",
            "general",
            "Exception during compilation: " + boost::diagnostic_information(_exception)
        ));
    }
    catch (...)
    {
        errors.append(formatError(
            false,
            "Exception",
            "general",
            "Unknown exception during compilation."
        ));
    }

    bool const analysisSuccess = m_compilerStack.state() >= CompilerStack::State::AnalysisSuccessful;
    bool const compilationSuccess = m_compilerStack.state() == CompilerStack::State::CompilationSuccessful;

    /// Inconsistent state - stop here to receive error reports from users
    if (!compilationSuccess && errors.empty())
        return formatFatalError("InternalCompilerError", "No error reported, but compilation failed.");

    Json::Value output = Json::objectValue;

    if (errors.size() > 0)
        output["errors"] = errors;

    if (!m_compilerStack.unhandledSMTLib2Queries().empty())
        for (string const& query: m_compilerStack.unhandledSMTLib2Queries())
            output["auxiliaryInputRequested"]["smtlib2queries"]["0x" + keccak256(query).hex()] = query;

    output["sources"] = Json::objectValue;
    unsigned sourceIndex = 0;
    for (string const& sourceName: analysisSuccess ? m_compilerStack.sourceNames() : vector<string>())
    {
        Json::Value sourceResult = Json::objectValue;
        sourceResult["id"] = sourceIndex++;
        if (isArtifactRequested(outputSelection, sourceName, "", "ast"))
            sourceResult["ast"] = ASTJsonConverter(false, m_compilerStack.sourceIndices()).toJson(m_compilerStack.ast(sourceName));
        if (isArtifactRequested(outputSelection, sourceName, "", "legacyAST"))
            sourceResult["legacyAST"] = ASTJsonConverter(true, m_compilerStack.sourceIndices()).toJson(m_compilerStack.ast(sourceName));
        output["sources"][sourceName] = sourceResult;
    }

    Json::Value contractsOutput = Json::objectValue;
    for (string const& contractName: compilationSuccess ? m_compilerStack.contractNames() : vector<string>())
    {
        size_t colon = contractName.rfind(':');
        solAssert(colon != string::npos, "");
        string file = contractName.substr(0, colon);
        string name = contractName.substr(colon + 1);

        // ABI, documentation and metadata
        Json::Value contractData(Json::objectValue);
        if (isArtifactRequested(outputSelection, file, name, "abi"))
            contractData["abi"] = m_compilerStack.contractABI(contractName);
        if (isArtifactRequested(outputSelection, file, name, "metadata"))
            contractData["metadata"] = m_compilerStack.metadata(contractName);
        if (isArtifactRequested(outputSelection, file, name, "userdoc"))
            contractData["userdoc"] = m_compilerStack.natspecUser(contractName);
        if (isArtifactRequested(outputSelection, file, name, "devdoc"))
            contractData["devdoc"] = m_compilerStack.natspecDev(contractName);

        // EVM
        Json::Value evmData(Json::objectValue);
        // @TODO: add ir
        if (isArtifactRequested(outputSelection, file, name, "evm.assembly"))
            evmData["assembly"] = m_compilerStack.assemblyString(contractName, createSourceList(_input));
        if (isArtifactRequested(outputSelection, file, name, "evm.legacyAssembly"))
            evmData["legacyAssembly"] = m_compilerStack.assemblyJSON(contractName, createSourceList(_input));
        if (isArtifactRequested(outputSelection, file, name, "evm.methodIdentifiers"))
            evmData["methodIdentifiers"] = m_compilerStack.methodIdentifiers(contractName);
        if (isArtifactRequested(outputSelection, file, name, "evm.gasEstimates"))
            evmData["gasEstimates"] = m_compilerStack.gasEstimates(contractName);

        if (isArtifactRequested(
            outputSelection,
            file,
            name,
            { "evm.bytecode", "evm.bytecode.object", "evm.bytecode.opcodes", "evm.bytecode.sourceMap", "evm.bytecode.linkReferences" }
        ))
            evmData["bytecode"] = collectEVMObject(
                m_compilerStack.object(contractName),
                m_compilerStack.sourceMapping(contractName)
            );

        if (isArtifactRequested(
            outputSelection,
            file,
            name,
            { "evm.deployedBytecode", "evm.deployedBytecode.object", "evm.deployedBytecode.opcodes", "evm.deployedBytecode.sourceMap", "evm.deployedBytecode.linkReferences" }
        ))
            evmData["deployedBytecode"] = collectEVMObject(
                m_compilerStack.runtimeObject(contractName),
                m_compilerStack.runtimeSourceMapping(contractName)
            );

        contractData["evm"] = evmData;

        if (!contractsOutput.isMember(file))
            contractsOutput[file] = Json::objectValue;

        contractsOutput[file][name] = contractData;
    }
    output["contracts"] = contractsOutput;

    return output;
}

Json::Value StandardCompiler::compile(Json::Value const& _input) noexcept
{
    try
    {
        return compileInternal(_input);
    }
    catch (Json::LogicError const& _exception)
    {
        return formatFatalError("InternalCompilerError", string("JSON logic exception: ") + _exception.what());
    }
    catch (Json::RuntimeError const& _exception)
    {
        return formatFatalError("InternalCompilerError", string("JSON runtime exception: ") + _exception.what());
    }
    catch (Exception const& _exception)
    {
        return formatFatalError("InternalCompilerError", "Internal exception in StandardCompiler::compileInternal: " + boost::diagnostic_information(_exception));
    }
    catch (...)
    {
        return formatFatalError("InternalCompilerError", "Internal exception in StandardCompiler::compileInternal");
    }
}

string StandardCompiler::compile(string const& _input) noexcept
{
    Json::Value input;
    string errors;
    try
    {
        if (!jsonParseStrict(_input, input, &errors))
            return jsonCompactPrint(formatFatalError("JSONError", errors));
    }
    catch (...)
    {
        return "{\"errors\":[{\"type\":\"JSONError\",\"component\":\"general\",\"severity\":\"error\",\"message\":\"Error parsing input JSON.\"}]}";
    }

    // cout << "Input: " << input.toStyledString() << endl;
    Json::Value output = compile(input);
    // cout << "Output: " << output.toStyledString() << endl;

    try
    {
        return jsonCompactPrint(output);
    }
    catch (...)
    {
        return "{\"errors\":[{\"type\":\"JSONError\",\"component\":\"general\",\"severity\":\"error\",\"message\":\"Error writing output JSON.\"}]}";
    }
}