/inifile-cpp

A header-only and easy to use Ini file parser for C++.

Primary LanguageC++MIT LicenseMIT

inifile-cpp

License CMake

inifile-cpp is a simple and easy to use single header-only ini file en- and decoder for C++.

Install

Install the headers using the CMake build system:

cd <path-to-repo>
mkdir build
cd build
cmake ..
make install

or simply copy the header file into your project and include it directly.

Usage

For examples on how to use and extend inifile-cpp for your custom needs, please have a look at the examples/ directory.

inifile-cpp allows loading data from any std::istream and requires a single function call or use the overloaded constructor.

#include <inicpp.h>

int main()
{
    // create istream object "is" ...

    // use function
    ini::IniFile myFirstIni;
    myFirstIni.decode(is);

    // or use the constructor
    ini::IniFile mySecondIni(is);
}

You can directly load ini-data from files by using the load() function. It requires a file path and automatically parses its contents:

#include <inicpp.h>

int main()
{
    // load an ini file
    ini::IniFile myIni;
    myIni.load("some/ini/path");
}

You can enable decoding of multi-line values using the setMultiLineValues(true) function. If you do this, field values may be continued on the next line, after indentation. Each line will be separated by the \n character in the final value, and the indentation will be removed.

#include <inicpp.h>

int main()
{
    // load an ini file
    ini::IniFile myIni;
    myIni.setMultiLineValues(true);
    myIni.load("some/ini/path");
}

Sections and fields can be accessed using the index operator []. The values can be converted to various native types:

bool myBool = myIni["Foo"]["myBool"].as<bool>();
char myChar = myIni["Foo"]["myChar"].as<char>();
unsigned char myUChar = myIni["Foo"]["myUChar"].as<unsigned char>();
int myInt = myIni["Foo"]["myInt"].as<int>();
unsigned int myUInt = myIni["Foo"]["myUInt"].as<unsigned int>();
long myLong = myIni["Foo"]["myLong"].as<long>();
unsigned long myULong = myIni["Foo"]["myULong"].as<unsigned long>();
float myFloat = myIni["Foo"]["myFloat"].as<float>();
double myDouble = myIni["Foo"]["myDouble"].as<double>();
std::string myStr = myIni["Foo"]["myStr"].as<std::string>();
const char *myStr2 = myIni["Foo"]["myStr"].as<const char*>();

Natively supported types are:

  • bool
  • char
  • unsigned char
  • short
  • unsigned short
  • int
  • unsigned int
  • long
  • unsigned long
  • float
  • double
  • std::string
  • const char *

Custom type conversions can be added by implementing specialized template of the ini::Convert<T> functor (see examples).

Values can be assigned to ini fileds just by using the assignment operator. The content of the inifile can then be written to any std::ostream object.

#include <inicpp.h>

int main()
{
    // create ostream object "os" ...

    ini::IniFile myIni;

    myIni["Foo"]["myInt"] = 1;
    myIni["Foo"]["myStr"] = "Hello world";
    myIni["Foo"]["myBool"] = true;
    myIni["Bar"]["myDouble"] = 1.2;

    myIni.encode(os);
}

You can directly save ini-data to files by using the save() function. It requires a file path and automatically stores the ini file contents:

#include <inicpp.h>

int main()
{
    ini::IniFile myIni;

    myIni["Foo"]["myInt"] = 1;
    myIni["Foo"]["myStr"] = "Hello world";
    myIni["Foo"]["myBool"] = true;
    myIni["Bar"]["myDouble"] = 1.2;

    myIni.save("some/ini/path");
}

You can define custom type conversions for inifile-cpp which will be automatically used by the assignment operator and the as() method of ini fields, e.g. you can add support for std::vector (see also examples):

// the conversion functor must live in the "ini" namespace
namespace ini
{
    /** Conversion functor to parse std::vectors from an ini field-
      * The generic template can be passed down to the vector. */
    template<typename T>
    struct Convert<std::vector<T>>
    {
        /** Decodes a std::vector from a string. */
        void decode(const std::string &value, std::vector<T> &result)
        {
            result.clear();

            // variable to store the decoded value of each element
            T decoded;
            // maintain a start and end pos within the string
            size_t startPos = 0;
            size_t endPos = 0;
            size_t cnt;

            while(endPos != std::string::npos)
            {
                if(endPos != 0)
                    startPos = endPos + 1;
                // search for the next comma as separator
                endPos = value.find(',', startPos);

                // if no comma was found use the rest of the string
                // as input
                if(endPos == std::string::npos)
                    cnt = value.size() - startPos;
                else
                    cnt = endPos - startPos;

                std::string tmp = value.substr(startPos, cnt);
                // use the conversion functor for the type contained in
                // the vector, so the vector can use any type that
                // is compatible with inifile-cpp
                Convert<T> conv;
                conv.decode(tmp, decoded);
                result.push_back(decoded);

            }
        }

        /** Encodes a std::vector to a string. */
        void encode(const std::vector<T> &value, std::string &result)
        {
            // variable to store the encoded element value
            std::string encoded;
            // string stream to build the result stream
            std::stringstream ss;
            for(size_t i = 0; i < value.size(); ++i)
            {
                // use the conversion functor for the type contained in
                // the vector, so the vector can use any type that
                // is compatible with inifile-cp
                Convert<T> conv;
                conv.encode(value[i], encoded);
                ss << encoded;

                // if this is not the last element add a comma as separator
                if(i != value.size() - 1)
                    ss << ',';
            }
            // store the created string in the result
            result = ss.str();
        }
    };
}

Contributors

Thanks to all contributors for extending, improving and fixing this small, but seemingly popular library: