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/*
* This source code is released into the public domain.
*/
module;
#include <cstdio>
#include <functional>
#include <iostream>
#include <map>
#include <print>
#include <ranges>
#include <string>
#include <utility>
#include <unistd.h>
module nihil.cli;
import nihil.core;
namespace nihil {
auto dispatch_command(int argc, char **argv) -> int
{
auto tree = build_command_tree();
// The caller should have stripped argv[0] already. find() will
// strip all the remaining elements except the last, which means
// argv[0] will be set to something reasonable for the next call
// to getopt().
// find() never returns nullptr; at worst it will return the
// root node.
auto const *node = tree.find(argc, argv);
// Get the command_node.
auto const &command = node->command();
// Reset getopt(3) for the command, in case main() used it already.
optreset = 1;
optind = 1;
/*
* Set the program name to the existing progname plus the full path
* to the command being invoked; this makes error messages nicer.
*/
auto *old_progname = ::getprogname();
{
auto cprogname = std::format("{} {}", ::getprogname(),
command->path());
::setprogname(cprogname.c_str());
}
// Invoke the command see what it returns.
auto ret = command->invoke(argc, argv);
// Restore the old progname.
::setprogname(old_progname);
// If the command produced an exit code, return it.
if (ret)
return *ret;
/*
* We have special handling for some errors.
*/
// Incomplete command: print the list of valid commands at this node.
if (ret.error() == errc::incomplete_command) {
std::print(std::cerr, "{}: usage:\n", ::getprogname());
node->print_commands();
return 1;
}
// We didn't recognise the error, so just print it and exit.
std::print(std::cerr, "{}\n", ret.error());
return 1;
}
} // namespace nihil
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