utils/Formatter.cpp

/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "Formatter.h"

#include <assert.h>

#include <android-base/logging.h>

namespace android {

Formatter::Formatter() : mFile(NULL /* invalid */), mIndentDepth(0), mAtStartOfLine(true) {}

Formatter::Formatter(FILE* file, size_t spacesPerIndent)
    : mFile(file == NULL ? stdout : file),
      mIndentDepth(0),
      mSpacesPerIndent(spacesPerIndent),
      mAtStartOfLine(true) {}

Formatter::~Formatter() {
    if (mFile != stdout) {
        fclose(mFile);
    }
    mFile = NULL;
}

void Formatter::indent(size_t level) {
    mIndentDepth += level;
}

void Formatter::unindent(size_t level) {
    assert(mIndentDepth >= level);
    mIndentDepth -= level;
}

Formatter& Formatter::indent(size_t level, const std::function<void(void)>& func) {
    this->indent(level);
    func();
    this->unindent(level);
    return *this;
}

Formatter& Formatter::indent(const std::function<void(void)>& func) {
    return this->indent(1, func);
}

Formatter& Formatter::block(const std::function<void(void)>& func) {
    (*this) << "{\n";
    this->indent(func);
    return (*this) << "}";
}

void Formatter::setLinePrefix(const std::string &prefix) {
    mLinePrefix = prefix;
}

void Formatter::unsetLinePrefix() {
    mLinePrefix = "";
}

Formatter &Formatter::endl() {
    return (*this) << "\n";
}

Formatter& Formatter::sIf(const std::string& cond, const std::function<void(void)>& block) {
    (*this) << "if (" << cond << ") ";
    return this->block(block);
}

Formatter& Formatter::sElseIf(const std::string& cond, const std::function<void(void)>& block) {
    (*this) << " else if (" << cond << ") ";
    return this->block(block);
}

Formatter& Formatter::sElse(const std::function<void(void)>& block) {
    (*this) << " else ";
    return this->block(block);
}

Formatter& Formatter::sFor(const std::string& stmts, const std::function<void(void)>& block) {
    (*this) << "for (" << stmts << ") ";
    return this->block(block);
}

Formatter& Formatter::sTry(const std::function<void(void)>& block) {
    (*this) << "try ";
    return this->block(block);
}

Formatter& Formatter::sCatch(const std::string& exception, const std::function<void(void)>& block) {
    (*this) << " catch (" << exception << ") ";
    return this->block(block);
}

Formatter& Formatter::sFinally(const std::function<void(void)>& block) {
    (*this) << " finally ";
    return this->block(block);
}

Formatter& Formatter::sWhile(const std::string& cond, const std::function<void(void)>& block) {
    (*this) << "while (" << cond << ") ";
    return this->block(block);
}

Formatter &Formatter::operator<<(const std::string &out) {
    const size_t len = out.length();
    size_t start = 0;
    while (start < len) {
        size_t pos = out.find('\n', start);

        if (pos == std::string::npos) {
            if (mAtStartOfLine) {
                fprintf(mFile, "%*s", (int)(mSpacesPerIndent * mIndentDepth), "");
                fprintf(mFile, "%s", mLinePrefix.c_str());
                mAtStartOfLine = false;
            }

            output(out.substr(start));
            break;
        }

        if (mAtStartOfLine && (pos > start || !mLinePrefix.empty())) {
            fprintf(mFile, "%*s", (int)(mSpacesPerIndent * mIndentDepth), "");
            fprintf(mFile, "%s", mLinePrefix.c_str());
        }

        if (pos == start) {
            fprintf(mFile, "\n");
            mAtStartOfLine = true;
        } else if (pos > start) {
            output(out.substr(start, pos - start + 1));
            mAtStartOfLine = true;
        }

        start = pos + 1;
    }

    return *this;
}

// NOLINT to suppress missing parentheses warning about __type__.
#define FORMATTER_INPUT_INTEGER(__type__)                       \
    Formatter& Formatter::operator<<(__type__ n) { /* NOLINT */ \
        return (*this) << std::to_string(n);                    \
    }

FORMATTER_INPUT_INTEGER(short);
FORMATTER_INPUT_INTEGER(unsigned short);
FORMATTER_INPUT_INTEGER(int);
FORMATTER_INPUT_INTEGER(unsigned int);
FORMATTER_INPUT_INTEGER(long);
FORMATTER_INPUT_INTEGER(unsigned long);
FORMATTER_INPUT_INTEGER(long long);
FORMATTER_INPUT_INTEGER(unsigned long long);
FORMATTER_INPUT_INTEGER(float);
FORMATTER_INPUT_INTEGER(double);
FORMATTER_INPUT_INTEGER(long double);

#undef FORMATTER_INPUT_INTEGER

// NOLINT to suppress missing parentheses warning about __type__.
#define FORMATTER_INPUT_CHAR(__type__)                          \
    Formatter& Formatter::operator<<(__type__ c) { /* NOLINT */ \
        return (*this) << std::string(1, (char)c);              \
    }

FORMATTER_INPUT_CHAR(char);
FORMATTER_INPUT_CHAR(signed char);
FORMATTER_INPUT_CHAR(unsigned char);

#undef FORMATTER_INPUT_CHAR

void Formatter::setNamespace(const std::string &space) {
    mSpace = space;
}

bool Formatter::isValid() const {
    return mFile != nullptr;
}

void Formatter::output(const std::string &text) const {
    CHECK(isValid());

    fprintf(mFile, "%s", text.c_str());
}

}  // namespace android