libgit2dart/lib/src/bindings/config.dart

import 'dart:ffi';
import 'package:ffi/ffi.dart';
import '../error.dart';
import 'libgit2_bindings.dart';
import '../util.dart';

/// Allocate a new configuration object
///
/// This object is empty, so you have to add a file to it before you can do
/// anything with it.
///
/// Throws a [LibGit2Error] if error occured.
Pointer<Pointer<git_config>> newConfig() {
  final out = calloc<Pointer<git_config>>();
  final error = libgit2.git_config_new(out);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }

  return out;
}

/// Create a new config instance containing a single on-disk file
///
/// Throws a [LibGit2Error] if error occured.
Pointer<Pointer<git_config>> open(String path) {
  final out = calloc<Pointer<git_config>>();
  final pathC = path.toNativeUtf8().cast<Int8>();
  final error = libgit2.git_config_open_ondisk(out, pathC);
  calloc.free(pathC);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }

  return out;
}

/// Open the global, XDG and system configuration files
///
/// Utility wrapper that finds the global, XDG and system configuration
/// files and opens them into a single prioritized config object that can
/// be used when accessing default config data outside a repository.
///
/// Throws a [LibGit2Error] if error occured.
Pointer<Pointer<git_config>> openDefault() {
  final out = calloc<Pointer<git_config>>();
  final error = libgit2.git_config_open_default(out);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }

  return out;
}

/// Locate the path to the global configuration file
///
/// The user or global configuration file is usually located in
/// `$HOME/.gitconfig`.
///
/// This method will try to guess the full path to that file, if the file
/// exists. The returned path may be used on any method call to load
/// the global configuration file.
///
/// This method will not guess the path to the xdg compatible config file
/// (`.config/git/config`).
///
/// Throws a [LibGit2Error] if error occured.
String findGlobal() {
  final out = calloc<git_buf>();
  final error = libgit2.git_config_find_global(out);
  final path = out.ref.ptr.cast<Utf8>().toDartString();
  calloc.free(out);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }

  return path;
}

/// Locate the path to the system configuration file
///
/// If /etc/gitconfig doesn't exist, it will look for %PROGRAMFILES%\Git\etc\gitconfig
///
/// Throws a [LibGit2Error] if error occured.
String findSystem() {
  final out = calloc<git_buf>();
  final error = libgit2.git_config_find_system(out);
  final path = out.ref.ptr.cast<Utf8>().toDartString();
  calloc.free(out);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }

  return path;
}

/// Locate the path to the global xdg compatible configuration file
///
/// The xdg compatible configuration file is usually located in
/// `$HOME/.config/git/config`.
///
/// Throws a [LibGit2Error] if error occured.
String findXdg() {
  final out = calloc<git_buf>();
  final error = libgit2.git_config_find_xdg(out);
  final path = out.ref.ptr.cast<Utf8>().toDartString();
  calloc.free(out);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }

  return path;
}

/// Get the value of a config variable.
///
/// Throws a [LibGit2Error] if error occured.
String getValue(Pointer<git_config> cfg, String variable) {
  final out = calloc<Pointer<git_config_entry>>();
  final name = variable.toNativeUtf8().cast<Int8>();
  final error = libgit2.git_config_get_entry(out, cfg, name);
  final value = out.value;
  calloc.free(out);
  calloc.free(name);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }

  return value.ref.value.cast<Utf8>().toDartString();
}

/// Set the value of a boolean config variable in the config file with the
/// highest level (usually the local one).
///
/// Throws a [LibGit2Error] if error occured.
void setBool(Pointer<git_config> cfg, String variable, bool value) {
  final name = variable.toNativeUtf8().cast<Int8>();
  final valueC = value ? 1 : 0;
  final error = libgit2.git_config_set_bool(cfg, name, valueC);
  calloc.free(name);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }
}

/// Set the value of an integer config variable in the config file with the
/// highest level (usually the local one).
///
/// Throws a [LibGit2Error] if error occured.
void setInt(Pointer<git_config> cfg, String variable, int value) {
  final name = variable.toNativeUtf8().cast<Int8>();
  final error = libgit2.git_config_set_int64(cfg, name, value);
  calloc.free(name);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }
}

/// Set the value of a string config variable in the config file with the
/// highest level (usually the local one).
///
/// Throws a [LibGit2Error] if error occured.
void setString(Pointer<git_config> cfg, String variable, String value) {
  final name = variable.toNativeUtf8().cast<Int8>();
  final valueC = value.toNativeUtf8().cast<Int8>();
  final error = libgit2.git_config_set_string(cfg, name, valueC);
  calloc.free(name);
  calloc.free(valueC);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }
}

/// Iterate over all the config variables.
Map<String, String> getEntries(Pointer<git_config> cfg) {
  final iterator = calloc<Pointer<git_config_iterator>>();
  final entry = calloc<Pointer<git_config_entry>>();
  libgit2.git_config_iterator_new(iterator, cfg);
  var error = 0;
  final entries = <String, String>{};

  while (error != -31) {
    error = libgit2.git_config_next(entry, iterator.value);
    entries[entry.value.ref.name.cast<Utf8>().toDartString()] =
        entry.value.ref.value.cast<Utf8>().toDartString();
  }
  calloc.free(entry);
  calloc.free(iterator);

  return entries;
}

/// Delete a config variable from the config file with the highest level
/// (usually the local one).
///
/// Throws a [LibGit2Error] if error occured.
void deleteEntry(Pointer<git_config> cfg, String variable) {
  final name = variable.toNativeUtf8().cast<Int8>();
  final error = libgit2.git_config_delete_entry(cfg, name);
  calloc.free(name);

  if (error < 0) {
    throw LibGit2Error(libgit2.git_error_last());
  }
}

/// Iterate over the values of a multivar
///
/// If regexp is present, then the iterator will only iterate over all
/// values which match the pattern.
List<String> getMultivarValue(
  Pointer<git_config> cfg,
  String variable,
  String? regexp,
) {
  final name = variable.toNativeUtf8().cast<Int8>();
  final regexpC = regexp?.toNativeUtf8().cast<Int8>() ?? nullptr;
  final iterator = calloc<Pointer<git_config_iterator>>();
  final entry = calloc<Pointer<git_config_entry>>();
  libgit2.git_config_multivar_iterator_new(iterator, cfg, name, regexpC);
  var error = 0;
  final entries = <String>[];

  while (error == 0) {
    error = libgit2.git_config_next(entry, iterator.value);
    if (error != -31) {
      entries.add(entry.value.ref.value.cast<Utf8>().toDartString());
    } else {
      break;
    }
  }

  calloc.free(name);
  calloc.free(regexpC);
  calloc.free(iterator);
  calloc.free(entry);

  return entries;
}

/// Set the value of a multivar config variable in the config file with the
/// highest level (usually the local one).
///
/// The regexp is applied case-sensitively on the value.
void setMultivarValue(
  Pointer<git_config> cfg,
  String variable,
  String regexp,
  String value,
) {
  final name = variable.toNativeUtf8().cast<Int8>();
  final regexpC = regexp.toNativeUtf8().cast<Int8>();
  final valueC = value.toNativeUtf8().cast<Int8>();
  libgit2.git_config_set_multivar(cfg, name, regexpC, valueC);

  calloc.free(name);
  calloc.free(regexpC);
  calloc.free(valueC);
}

/// Deletes one or several values from a multivar in the config file
/// with the highest level (usually the local one).
///
/// The regexp is applied case-sensitively on the value.
void deleteMultivar(
  Pointer<git_config> cfg,
  String variable,
  String regexp,
) {
  final name = variable.toNativeUtf8().cast<Int8>();
  final regexpC = regexp.toNativeUtf8().cast<Int8>();
  libgit2.git_config_delete_multivar(cfg, name, regexpC);

  calloc.free(name);
  calloc.free(regexpC);
}