nix-gh/src/nix/main.cc

116 lines
2.9 KiB
C++

#include <algorithm>
#include "command.hh"
#include "common-args.hh"
#include "eval.hh"
#include "globals.hh"
#include "legacy.hh"
#include "shared.hh"
#include "store-api.hh"
#include "progress-bar.hh"
#include "finally.hh"
extern std::string chrootHelperName;
void chrootHelper(int argc, char * * argv);
namespace nix {
std::string programPath;
struct NixArgs : virtual MultiCommand, virtual MixCommonArgs
{
NixArgs() : MultiCommand(*RegisterCommand::commands), MixCommonArgs("nix")
{
mkFlag()
.longName("help")
.description("show usage information")
.handler([&]() { showHelpAndExit(); });
mkFlag()
.longName("help-config")
.description("show configuration options")
.handler([&]() {
std::cout << "The following configuration options are available:\n\n";
Table2 tbl;
std::map<std::string, Config::SettingInfo> settings;
globalConfig.getSettings(settings);
for (const auto & s : settings)
tbl.emplace_back(s.first, s.second.description);
printTable(std::cout, tbl);
throw Exit();
});
mkFlag()
.longName("version")
.description("show version information")
.handler([&]() { printVersion(programName); });
}
void printFlags(std::ostream & out) override
{
Args::printFlags(out);
std::cout <<
"\n"
"In addition, most configuration settings can be overriden using '--<name> <value>'.\n"
"Boolean settings can be overriden using '--<name>' or '--no-<name>'. See 'nix\n"
"--help-config' for a list of configuration settings.\n";
}
void showHelpAndExit()
{
printHelp(programName, std::cout);
std::cout << "\nNote: this program is EXPERIMENTAL and subject to change.\n";
throw Exit();
}
};
void mainWrapped(int argc, char * * argv)
{
/* The chroot helper needs to be run before any threads have been
started. */
if (argc > 0 && argv[0] == chrootHelperName) {
chrootHelper(argc, argv);
return;
}
initNix();
initGC();
programPath = argv[0];
string programName = baseNameOf(programPath);
{
auto legacy = (*RegisterLegacyCommand::commands)[programName];
if (legacy) return legacy(argc, argv);
}
verbosity = lvlError;
settings.verboseBuild = false;
NixArgs args;
args.parseCmdline(argvToStrings(argc, argv));
initPlugins();
if (!args.command) args.showHelpAndExit();
Finally f([]() { stopProgressBar(); });
if (isatty(STDERR_FILENO))
startProgressBar();
args.command->prepare();
args.command->run();
}
}
int main(int argc, char * * argv)
{
return nix::handleExceptions(argv[0], [&]() {
nix::mainWrapped(argc, argv);
});
}