userspace: Remove start-gui from shell builtins and make it an alias

This makes way more sense :D

userspace/programs/Shell/main.cpp

@@ -11,6 +11,7 @@
 #include <pwd.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/select.h>
 #include <sys/stat.h>
 #include <sys/wait.h>
 #include <termios.h>
@@ -35,6 +36,7 @@ struct SingleCommand
 
 struct PipedCommand
 {
+	bool background;
 	BAN::Vector<SingleCommand> commands;
 };
 
@@ -61,7 +63,7 @@ struct BuiltinCommand
 };
 static BAN::HashMap<BAN::String, BuiltinCommand> s_builtin_commands;
 
-static BAN::HashMap<BAN::String, BAN::Vector<BAN::String>> s_aliases;
+static BAN::HashMap<BAN::String, BAN::String> s_aliases;
 
 static BAN::StringView strip_whitespace(BAN::StringView sv)
 {
@@ -208,7 +210,7 @@ static BAN::Optional<BAN::String> parse_dollar(BAN::StringView command, size_t&
 	return temp;
 }
 
-static SingleCommand parse_single_command(BAN::StringView command_view, bool parse_aliases = true)
+static SingleCommand parse_single_command(BAN::StringView command_view)
 {
 	constexpr auto can_escape =
 		[](char c)
@@ -332,27 +334,19 @@ static SingleCommand parse_single_command(BAN::StringView command_view, bool par
 
 	MUST(result.arguments.push_back(BAN::move(current_argument)));
 
-	if (parse_aliases)
-	{
-		BAN::HashSet<BAN::String> matched_aliases;
-		while (!result.arguments.empty() && !matched_aliases.contains(result.arguments.front()))
-		{
-			auto it = s_aliases.find(result.arguments.front());
-			if (it == s_aliases.end())
-				break;
-			MUST(matched_aliases.insert(result.arguments.front()));
-			result.arguments.remove(0);
-			for (size_t i = 0; i < it->value.size(); i++)
-				MUST(result.arguments.insert(i, it->value[i]));
-		}
-	}
-
 	return BAN::move(result);
 }
 
 static PipedCommand parse_piped_command(BAN::StringView command_view)
 {
+	while (!command_view.empty() && isspace(command_view.back()))
+		command_view = command_view.substring(0, command_view.size() - 1);
+	const bool background = !command_view.empty() && command_view.back() == '&';
+	if (background)
+		command_view = command_view.substring(0, command_view.size() - 1);
+
 	PipedCommand result;
+	result.background = background;
 
 	for (size_t i = 0; i < command_view.size(); i++)
 	{
@@ -385,8 +379,88 @@ static PipedCommand parse_piped_command(BAN::StringView command_view)
 	return BAN::move(result);
 }
 
+static BAN::String parse_aliases(BAN::StringView command_view)
+{
+	while (!command_view.empty() && isspace(command_view.front()))
+		command_view = command_view.substring(1);
+
+	BAN::String result;
+	MUST(result.append(command_view));
+
+	BAN::HashSet<BAN::String> matched_aliases;
+
+	for (size_t i = 0; i < result.size();)
+	{
+		size_t command_len = 0;
+		for (; command_len < result.size() - i; command_len++)
+			if (isspace(result[i + command_len]))
+				break;
+		auto command = result.sv().substring(i, command_len);
+
+		if (!matched_aliases.contains(command))
+		{
+			auto it = s_aliases.find(command);
+			if (it != s_aliases.end())
+			{
+				MUST(matched_aliases.insert(command));
+				for (size_t j = 0; j < command_len; j++)
+					result.remove(i);
+				MUST(result.insert(it->value, i));
+				continue;
+			}
+		}
+
+		matched_aliases.clear();
+
+		for (; i < result.size(); i++)
+		{
+			bool should_break = false;
+
+			const char current = result[i];
+			switch (current)
+			{
+				case '\\':
+					i++;
+					break;
+				case '\'':
+				case '"':
+					while (++i < result.size())
+					{
+						if (result[i] == current)
+							break;
+						if (result[i] == '\\')
+							i++;
+					}
+					break;
+				case '|':
+				case '&':
+					if (i + 1 < result.size() && result[i + 1] == current)
+						i++;
+					else if (current == '&')
+						break;
+					// fall through
+				case ';':
+					i++;
+					should_break = true;
+					break;
+			}
+
+			if (should_break)
+				break;
+		}
+
+		while (i < result.size() && isspace(result[i]))
+			i++;
+	}
+
+	return BAN::move(result);
+}
+
 static CommandList parse_command_list(BAN::StringView command_view)
 {
+	const auto command_with_aliases_parsed = parse_aliases(command_view);
+	command_view = command_with_aliases_parsed.sv();
+
 	CommandList result;
 	CommandList::Condition next_condition = CommandList::Condition::Always;
 	for (size_t i = 0; i < command_view.size(); i++)
@@ -447,7 +521,7 @@ static CommandList parse_command_list(BAN::StringView command_view)
 	return BAN::move(result);
 }
 
-static int execute_command(const SingleCommand& command, int fd_in, int fd_out);
+static int execute_command(const SingleCommand& command, int fd_in, int fd_out, bool background);
 
 static int source_script(const BAN::String& path);
 
@@ -533,23 +607,10 @@ static void install_builtin_commands()
 	MUST(s_builtin_commands.emplace("alias"_sv,
 		[](const SingleCommand& command, FILE* fout, int, int) -> int
 		{
-			const auto print_alias =
-				[fout](const BAN::String& alias, const BAN::Vector<BAN::String>& value)
-				{
-					fprintf(fout, "%s='", alias.data());
-					for (size_t i = 0; i < value.size(); i++)
-					{
-						if (i != 0)
-							fprintf(fout, " ");
-						fprintf(fout, "%s", value[i].data());
-					}
-					fprintf(fout, "'\n");
-				};
-
 			if (command.arguments.size() == 1)
 			{
 				for (const auto& [alias, value] : s_aliases)
-					print_alias(alias, value);
+					fprintf(fout, "%s='%s'\n", alias.data(), value.data());
 				return 0;
 			}
 
@@ -562,17 +623,16 @@ static void install_builtin_commands()
 				{
 					auto it = s_aliases.find(command.arguments[i]);
 					if (it != s_aliases.end())
-						print_alias(command.arguments[i], it->value);
+						fprintf(fout, "%s='%s'\n", command.arguments[i].data(), it->value.data());
 				}
 				else
 				{
 					auto alias = command.arguments[i].sv().substring(0, idx.value());
 					auto value = command.arguments[i].sv().substring(idx.value() + 1);
-					auto parsed_alias = parse_single_command(value, false);
 
 					if (s_aliases.contains(alias))
 						s_aliases.remove(alias);
-					MUST(s_aliases.insert(alias, BAN::move(parsed_alias.arguments)));
+					MUST(s_aliases.insert(alias, value));
 				}
 			}
 
@@ -643,7 +703,7 @@ static void install_builtin_commands()
 			if (clock_gettime(CLOCK_MONOTONIC, &start) == -1)
 				ERROR_RETURN("clock_gettime", 1);
 
-			int ret = execute_command(timed_command, fd_in, fd_out);
+			int ret = execute_command(timed_command, fd_in, fd_out, false);
 
 			if (clock_gettime(CLOCK_MONOTONIC, &end) == -1)
 				ERROR_RETURN("clock_gettime", 1);
@@ -660,24 +720,9 @@ static void install_builtin_commands()
 			return ret;
 		}
 	));
-
-	MUST(s_builtin_commands.emplace("start-gui"_sv,
-		[](const SingleCommand&, FILE*, int, int) -> int
-		{
-			const pid_t pid = fork();
-			if (pid == -1)
-				return 1;
-			if (pid == 0)
-				execl("/bin/WindowServer", "WindowServer", NULL);
-			if (fork() == 0)
-				execl("/bin/Terminal", "Terminal", NULL);
-			waitpid(pid, nullptr, 0);
-			return 0;
-		}
-	));
 }
 
-static pid_t execute_command_no_wait(const SingleCommand& command, int fd_in, int fd_out, pid_t pgrp)
+static pid_t execute_command_no_wait(const SingleCommand& command, int fd_in, int fd_out, pid_t pgrp, bool background)
 {
 	ASSERT(!command.arguments.empty());
 
@@ -760,7 +805,9 @@ static pid_t execute_command_no_wait(const SingleCommand& command, int fd_in, in
 	if (pid == -1)
 		ERROR_RETURN("fork", -1);
 
-	if (pgrp == 0 && isatty(0))
+	if (background)
+		;
+	else if (pgrp == 0 && isatty(0))
 	{
 		if(setpgid(pid, pid) == -1)
 			perror("setpgid");
@@ -775,11 +822,13 @@ static pid_t execute_command_no_wait(const SingleCommand& command, int fd_in, in
 	return pid;
 }
 
-static int execute_command(const SingleCommand& command, int fd_in, int fd_out)
+static int execute_command(const SingleCommand& command, int fd_in, int fd_out, bool background)
 {
-	const pid_t pid = execute_command_no_wait(command, fd_in, fd_out, 0);
+	const pid_t pid = execute_command_no_wait(command, fd_in, fd_out, 0, background);
 	if (pid == -1)
 		return 1;
+	if (background)
+		return 0;
 
 	int status;
 	if (waitpid(pid, &status, 0) == -1)
@@ -804,7 +853,7 @@ static int execute_piped_commands(const PipedCommand& piped_command)
 		auto& command = piped_command.commands.front();
 		if (auto ret = execute_builtin(command, STDIN_FILENO, STDOUT_FILENO); ret.has_value())
 			return ret.value();
-		return execute_command(command, STDIN_FILENO, STDOUT_FILENO);
+		return execute_command(command, STDIN_FILENO, STDOUT_FILENO, piped_command.background);
 	}
 
 	BAN::Vector<int> exit_codes(piped_command.commands.size(), 0);
@@ -830,7 +879,7 @@ static int execute_piped_commands(const PipedCommand& piped_command)
 			exit_codes[i] = builtin_ret.value();
 		else
 		{
-			pid_t pid = execute_command_no_wait(piped_command.commands[i], next_stdin, pipefd[1], pgrp);
+			const pid_t pid = execute_command_no_wait(piped_command.commands[i], next_stdin, pipefd[1], pgrp, piped_command.background);
 			processes[i] = pid;
 			if (pgrp == 0)
 				pgrp = pid;
@@ -843,6 +892,9 @@ static int execute_piped_commands(const PipedCommand& piped_command)
 		next_stdin = pipefd[0];
 	}
 
+	if (piped_command.background)
+		return 0;
+
 	for (size_t i = 0; i < piped_command.commands.size(); i++)
 	{
 		if (processes[i] == -1)
@@ -882,8 +934,18 @@ static int parse_and_execute_command(BAN::StringView command)
 	tcsetattr(0, TCSANOW, &old_termios);
 
 	last_return = 0;
-	for (const auto& [expression, condition] : command_list.commands)
+
+	for (size_t i = 0; i < command_list.commands.size(); i++)
 	{
+		const auto& [expression, condition] = command_list.commands[i];
+
+		const auto parsed_command = parse_piped_command(expression);
+		if (parsed_command.background && i + 1 < command_list.commands.size() && command_list.commands[i + 1].condition != CommandList::Condition::Always)
+		{
+			printf("invalid background command with conditional execution\n");
+			break;
+		}
+
 		bool should_run = false;
 		switch (condition)
 		{
@@ -901,7 +963,9 @@ static int parse_and_execute_command(BAN::StringView command)
 		if (!should_run)
 			continue;
 
-		last_return = execute_piped_commands(parse_piped_command(expression));
+		int return_value = execute_piped_commands(parsed_command);
+		if (!parsed_command.background)
+			last_return = return_value;
 	}
 
 	tcsetattr(0, TCSANOW, &new_termios);
@@ -1243,6 +1307,101 @@ static void print_prompt()
 	fflush(stdout);
 }
 
+static bool detect_cursor_position_support()
+{
+	constexpr auto getchar_nonblock =
+		[]() -> char
+		{
+			fd_set fds;
+			FD_ZERO(&fds);
+			FD_SET(STDIN_FILENO, &fds);
+
+			timeval timeout;
+			timeout.tv_sec = 0;
+			timeout.tv_usec = 100'000;
+
+			int nselect = select(STDIN_FILENO + 1, &fds, nullptr, nullptr, &timeout);
+			if (nselect != 1)
+				return '\0';
+
+			char ch;
+			if (read(STDIN_FILENO, &ch, 1) != 1)
+				return '\0';
+			return ch;
+		};
+
+	if (write(STDOUT_FILENO, "\e[6n", 4) != 4)
+		return false;
+
+	char ch = getchar_nonblock();
+	if (ch != '\e')
+	{
+		if (ch != '\0')
+			ungetc(ch, stdin);
+		return false;
+	}
+	if (getchar_nonblock() != '[')
+		return false;
+
+	int cur;
+	while (isdigit(cur = getchar_nonblock()))
+		;
+	if (cur != ';')
+		return false;
+	while (isdigit(cur = getchar_nonblock()))
+		;
+	if (cur != 'R')
+		return false;
+
+	return true;
+}
+
+struct CursorPosition
+{
+	int x;
+	int y;
+};
+
+static BAN::Optional<CursorPosition> try_read_cursor_position()
+{
+#if __banan_os__
+	return {};
+#endif
+
+	static BAN::Optional<bool> s_supports_cursor_position;
+	if (!s_supports_cursor_position.has_value())
+		s_supports_cursor_position = detect_cursor_position_support();
+
+	if (!s_supports_cursor_position.value())
+		return {};
+
+	if (write(STDOUT_FILENO, "\e[6n", 4) != 4)
+		return {};
+
+	char ch = getchar();
+	if (ch != '\e')
+	{
+		ungetc(ch, stdin);
+		return {};
+	}
+	if (getchar() != '[')
+		return {};
+
+	int cur, x = 0, y = 0;
+	while (isdigit(cur = getchar()))
+		y = (y * 10) + (cur - '0');
+	if (cur != ';')
+		return {};
+	while (isdigit(cur = getchar()))
+		x = (x * 10) + (cur - '0');
+	if (cur != 'R')
+		return {};
+
+	if (x > 0) x--;
+	if (y > 0) y--;
+	return CursorPosition { x, y };
+}
+
 int main(int argc, char** argv)
 {
 	realpath(argv[0], s_shell_path);
@@ -1466,6 +1625,10 @@ int main(int argc, char** argv)
 				MUST(history.push_back(buffers[index]));
 				buffers = history;
 				MUST(buffers.emplace_back(""_sv));
+
+				auto cursor_pos = try_read_cursor_position();
+				if (cursor_pos.has_value() && cursor_pos->x > 0)
+					printf("\e[7m%%\e[m\n");
 			}
 			print_prompt();
 			index = buffers.size() - 1;
@@ -1509,12 +1672,12 @@ int main(int argc, char** argv)
 				}
 			);
 
-			for (size_t i = 0; i < completions.size() - 1; i++)
+			for (size_t i = 1; i < completions.size();)
 			{
-				if (completions[i] != completions[i + 1])
-					continue;
-				completions.remove(i + 1);
-				i--;
+				if (completions[i - 1] == completions[i])
+					completions.remove(i);
+				else
+					i++;
 			}
 
 			if (completions.empty())
@@ -1543,9 +1706,28 @@ int main(int argc, char** argv)
 
 			if (all_match_len)
 			{
-				col += all_match_len;
-				MUST(buffers[index].append(completions.front().sv().substring(0, all_match_len)));
-				printf("%.*s", (int)all_match_len, completions.front().data());
+				auto completion = completions.front().sv().substring(0, all_match_len);
+
+				BAN::String temp_escaped;
+				if (should_escape_spaces)
+				{
+					MUST(temp_escaped.append(completion));
+					for (size_t i = 0; i < temp_escaped.size(); i++)
+					{
+						if (!isspace(temp_escaped[i]))
+							continue;
+						MUST(temp_escaped.insert('\\', i));
+						i++;
+					}
+					completion = temp_escaped.sv();
+
+					if (!buffers[index].empty() && buffers[index].back() == '\\' && completion.front() == '\\')
+						completion = completion.substring(1);
+				}
+
+				col += completion.size();
+				MUST(buffers[index].append(completion));
+				printf("%.*s", (int)completion.size(), completion.data());
 				fflush(stdout);
 				break;
 			}

userspace/programs/ls/main.cpp

@@ -202,7 +202,8 @@ int list_directory(const BAN::String& path, config_t config)
 		{
 			if (i > 0)
 				printf(" ");
-			printf("%s%s\e[m", entry_color(entries[i].st.st_mode), entries[i].name.data());
+			const char* format = entries[i].name.sv().contains(' ') ? "'%s%s\e[m'" : "%s%s\e[m";
+			printf(format, entry_color(entries[i].st.st_mode), entries[i].name.data());
 		}
 		printf("\n");
 		return ret;