cli: improve command dispatch a bit

1 files changed, 0 insertions, 267 deletions

diff --git a/nihil.cli/command_map.cc b/nihil.cli/command_map.cc
deleted file mode 100644
index c656c62..0000000
--- a/nihil.cli/command_map.cc
+++ /dev/null
@@ -1,267 +0,0 @@
-/*
- * This source code is released into the public domain.
- */
-
-module;
-
-#include <cstdio>
-#include <functional>
-#include <iostream>
-#include <map>
-#include <ranges>
-#include <string>
-#include <utility>
-
-#include <unistd.h>
-
-module nihil.cli;
-
-/*
- * command_map represents a hierarchical list of commands.  At each level,
- * a command is mapped to a handler, which can either be a function, in
- * which case we execute the function, or another command_map, in which
- * case we invoke the new map
- */
-
-namespace nihil {
-
-/*
- * The string tree we store our commands in.  This is sort of like a very
- * basic hierarchical std::map.  Keys are provided as a range of values,
- * typically from argv.
- */
-
-struct command_tree_node final {
-	command_tree_node()
-		: _this_word("")
-	{
-	}
-
-	command_tree_node(std::string_view this_word)
-		: _this_word(this_word)
-	{
-	}
-
-	command_tree_node(std::string_view this_word,
-			  command value)
-		: _this_word(this_word)
-		, _value(std::move(value))
-	{
-	}
-
-	/*
-	 * Return a child node, or NULL if the child doesn't exist.
-	 */
-	auto get_child(this command_tree_node const &self,
-		       std::string_view child)
-		-> command_tree_node const *
-	{
-		if (auto it = self.children.find(std::string(child));
-		    it != self.children.end())
-			return &it->second;
-
-		return nullptr;
-	}
-
-	auto get_child(this command_tree_node &self,
-		       std::string_view child)
-		-> command_tree_node *
-	{
-		if (auto it = self.children.find(std::string(child));
-		    it != self.children.end())
-			return &it->second;
-
-		return nullptr;
-	}
-
-	/*
-	 * Return a child node if it exists, or insert a new empty node.
-	 */
-	auto get_or_create_child(this command_tree_node &self,
-				 std::string_view child)
-		-> command_tree_node *
-	{
-		if (auto ptr = self.get_child(child); ptr != nullptr)
-			return ptr;
-
-		auto [it, ok] = self.children.emplace(
-					child, command_tree_node(child));
-		return &it->second;
-	}
-
-	/*
-	 * Return this node's value.
-	 */
-	auto value(this command_tree_node const &self)
-		-> std::optional<command> const &
-	{
-		return self._value;
-	}
-
-	/*
-	 * Set this node's value.
-	 */
-	auto value(this command_tree_node &self, command value) -> void
-	{
-		self._value = std::move(value);
-	}
-
-	/*
-	 * Print this node's children in a form useful to humans.
-	 */
-	auto print_commands(this command_tree_node const &self,
-			    std::string_view prefix) -> void
-	{
-		for (auto &&[name, node] : self.children) {
-			std::print("  {} {}\n", prefix, name);
-		}
-	}
-
-private:
-	std::string _this_word;
-	std::optional<command> _value;
-	std::unordered_map<std::string, command_tree_node> children;
-};
-
-struct command_tree {
-	/*
-	 * Add a node to the tree.  Returns false if the node already exists.
-	 */
-	auto insert(this command_tree &self,
-		    std::ranges::range auto &&path,
-		    command value)
-		-> bool
-	{
-		auto *this_node = &self._root_node;
-
-		// Find the node for this key.
-		for (auto &&next : path) {
-			auto this_word = std::string_view(next);
-			this_node = this_node->get_or_create_child(this_word);
-		}
-
-		if (this_node->value()) {
-			// The value already exists.
-			return false;
-		}
-
-		// Set the new value.
-		this_node->value(std::move(value));
-		return true;
-	}
-
-	/*
-	 * Find a node in the tree.  Unlike insert(), iteration stops when
-	 * we find any node with a value.
-	 */
-	auto find(this command_tree const &self, int &argc, char **&argv)
-		-> std::optional<command>
-	{
-		auto *this_node = &self._root_node;
-
-		// Assume the caller already stripped the program name from
-		// argv.  This is usually the case since they would have
-		// called getopt().
-
-		// Store the command bits we got so far, so we can print them
-		// in the usage error if needed.
-		auto path = std::string();
-
-		while (argv[0] != nullptr) {
-			auto next = std::string_view(argv[0]);
-
-			auto *next_node = this_node->get_child(next);
-
-			if (next_node == nullptr) {
-				// The node doesn't exist, so this command is
-				// not valid.  Print a list of valid commands.
-				std::print(std::cerr,
-					   "{}: unknown command: {} {}\n",
-					   ::getprogname(), path, next);
-				std::print(std::cerr,
-					   "{}: expected one of:\n",
-					   ::getprogname());
-
-				this_node->print_commands(path);
-				return {};
-			}
-
-			this_node = next_node;
-
-			if (this_node->value())
-				// This node has a value, so return it.
-				return {this_node->value()};
-
-			if (!path.empty())
-				path += ' ';
-			path += next;
-			--argc;
-			++argv;
-		}
-
-		// We didn't find a value, so the key was incomplete.
-		std::print(std::cerr, "{}: {} command; expected:\n",
-			   ::getprogname(),
-			   path.empty() ? "missing" : "incomplete");
-		this_node->print_commands(path);
-
-		return {};
-	}
-
-private:
-	command_tree_node _root_node;
-};
-
-/*
- * The global command map.
- */
-auto get_commands() -> command_tree & {
-	static auto commands = command_tree();
-	return commands;
-}
-
-auto register_command(std::string_view path, command *cmd) noexcept -> void
-try {
-	auto &commands = get_commands();
-	if (commands.insert(path | std::views::split(' '), *cmd) == false) {
-		std::printf("command registration failed\n");
-		std::abort();
-	}
-} catch (...) {
-	std::printf("command registration failed\n");
-	std::abort();
-}
-
-auto dispatch_command(int argc, char **argv) -> int
-{
-	auto &commands = get_commands();
-
-	// 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().
-
-	auto node = commands.find(argc, argv);
-
-	if (!node)
-		// find() already printed the error message
-		return 1;
-
-	// Reset getopt here for the command to use.
-	optreset = 1;
-	optind = 1;
-
-	// Calling setprogname() makes error messages more relevant.
-	auto cprogname = std::format("{} {}", ::getprogname(),
-				     node->path());
-	::setprogname(cprogname.c_str());
-
-	return node->invoke(argc, argv);
-}
-
-void print_usage(std::string_view)
-{
-//	get_root_node().print_usage(std::string(prefix));
-}
-
-} // namespace nihil