ladybird/Userland/Shell/Shell.h
Liav A fb60db7b00 Shell: Add builtin command to reset the internal state
The new builtin command "reset" now resets the entire internal state by
virtually destructing the Shell state and re-constructing it.

This helps for example when setting a new hostname and wanting to view
it in the current Shell program.
2023-08-11 18:48:53 +03:30

602 lines
21 KiB
C++

/*
* Copyright (c) 2020-2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include "Job.h"
#include "Parser.h"
#include <AK/Array.h>
#include <AK/CircularQueue.h>
#include <AK/DeprecatedString.h>
#include <AK/HashMap.h>
#include <AK/IntrusiveList.h>
#include <AK/StackInfo.h>
#include <AK/StringBuilder.h>
#include <AK/StringView.h>
#include <AK/Types.h>
#include <AK/Vector.h>
#include <LibCore/EventReceiver.h>
#include <LibCore/Notifier.h>
#include <LibLine/Editor.h>
#include <LibMain/Main.h>
#include <termios.h>
#define ENUMERATE_SHELL_BUILTINS() \
__ENUMERATE_SHELL_BUILTIN(alias, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(where, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(cd, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(cdh, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(pwd, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(type, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(exec, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(exit, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(export, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(glob, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(unalias, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(unset, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(history, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(umask, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(not, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(dirs, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(pushd, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(popd, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(setopt, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(shift, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(source, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(time, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(jobs, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(disown, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(fg, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(bg, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(wait, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(dump, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(kill, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(reset, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(noop, InAllModes) \
__ENUMERATE_SHELL_BUILTIN(break, OnlyInPOSIXMode) \
__ENUMERATE_SHELL_BUILTIN(continue, OnlyInPOSIXMode) \
__ENUMERATE_SHELL_BUILTIN(read, OnlyInPOSIXMode) \
__ENUMERATE_SHELL_BUILTIN(run_with_env, OnlyInPOSIXMode) \
__ENUMERATE_SHELL_BUILTIN(argsparser_parse, InAllModes)
#define ENUMERATE_SHELL_OPTIONS() \
__ENUMERATE_SHELL_OPTION(inline_exec_keep_empty_segments, false, "Keep empty segments in inline execute $(...)") \
__ENUMERATE_SHELL_OPTION(verbose, false, "Announce every command that is about to be executed") \
__ENUMERATE_SHELL_OPTION(invoke_program_for_autocomplete, false, "Attempt to use the program being completed itself for autocompletion via --complete")
#define ENUMERATE_SHELL_IMMEDIATE_FUNCTIONS() \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(concat_lists) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(length) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(length_across) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(remove_suffix) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(remove_prefix) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(regex_replace) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(filter_glob) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(split) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(join) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(value_or_default) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(assign_default) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(error_if_empty) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(null_or_alternative) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(defined_value_or_default) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(assign_defined_default) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(error_if_unset) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(null_if_unset_or_alternative) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(length_of_variable) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(reexpand) \
__ENUMERATE_SHELL_IMMEDIATE_FUNCTION(math)
namespace Shell {
class Shell;
enum class POSIXModeRequirement {
OnlyInPOSIXMode,
InAllModes,
};
class Shell : public Core::EventReceiver {
C_OBJECT(Shell);
public:
constexpr static auto local_init_file_path = "~/.shellrc";
constexpr static auto global_init_file_path = "/etc/shellrc";
constexpr static auto local_posix_init_file_path = "~/.posixshrc";
constexpr static auto global_posix_init_file_path = "/etc/posixshrc";
bool should_format_live() const { return m_should_format_live; }
void set_live_formatting(bool value) { m_should_format_live = value; }
void setup_signals();
void setup_keybinds();
struct SourcePosition {
DeprecatedString source_file;
DeprecatedString literal_source_text;
Optional<AST::Position> position;
};
struct RunnablePath {
enum class Kind {
Builtin,
Function,
Alias,
Executable,
};
Kind kind;
DeprecatedString path;
bool operator<(RunnablePath const& other) const
{
return path < other.path;
}
bool operator==(RunnablePath const&) const = default;
};
struct RunnablePathComparator {
int operator()(RunnablePath const& lhs, RunnablePath const& rhs)
{
if (lhs.path > rhs.path)
return 1;
if (lhs.path < rhs.path)
return -1;
return 0;
}
int operator()(StringView lhs, RunnablePath const& rhs)
{
if (lhs > rhs.path)
return 1;
if (lhs < rhs.path)
return -1;
return 0;
}
};
int run_command(StringView, Optional<SourcePosition> = {});
Optional<RunnablePath> runnable_path_for(StringView);
Optional<DeprecatedString> help_path_for(Vector<RunnablePath> visited, RunnablePath const& runnable_path);
ErrorOr<RefPtr<Job>> run_command(const AST::Command&);
Vector<NonnullRefPtr<Job>> run_commands(Vector<AST::Command>&);
bool run_file(DeprecatedString const&, bool explicitly_invoked = true);
ErrorOr<bool> run_builtin(const AST::Command&, Vector<NonnullRefPtr<AST::Rewiring>> const&, int& retval);
bool has_builtin(StringView) const;
ErrorOr<RefPtr<AST::Node>> run_immediate_function(StringView name, AST::ImmediateExpression& invoking_node, Vector<NonnullRefPtr<AST::Node>> const&);
static bool has_immediate_function(StringView);
void block_on_job(RefPtr<Job>);
void block_on_pipeline(RefPtr<AST::Pipeline>);
DeprecatedString prompt() const;
static DeprecatedString expand_tilde(StringView expression);
static Vector<DeprecatedString> expand_globs(StringView path, StringView base);
static Vector<DeprecatedString> expand_globs(Vector<StringView> path_segments, StringView base);
ErrorOr<Vector<AST::Command>> expand_aliases(Vector<AST::Command>);
DeprecatedString resolve_path(DeprecatedString) const;
DeprecatedString resolve_alias(StringView) const;
static bool has_history_event(StringView);
ErrorOr<RefPtr<AST::Value const>> get_argument(size_t) const;
ErrorOr<RefPtr<AST::Value const>> look_up_local_variable(StringView) const;
ErrorOr<DeprecatedString> local_variable_or(StringView, DeprecatedString const&) const;
void set_local_variable(DeprecatedString const&, RefPtr<AST::Value>, bool only_in_current_frame = false);
void unset_local_variable(StringView, bool only_in_current_frame = false);
void define_function(DeprecatedString name, Vector<DeprecatedString> argnames, RefPtr<AST::Node> body);
bool has_function(StringView);
bool invoke_function(const AST::Command&, int& retval);
DeprecatedString format(StringView, ssize_t& cursor) const;
RefPtr<Line::Editor> editor() const { return m_editor; }
enum class LocalFrameKind {
FunctionOrGlobal,
Block,
};
struct LocalFrame {
LocalFrame(DeprecatedString name, HashMap<DeprecatedString, RefPtr<AST::Value>> variables, LocalFrameKind kind = LocalFrameKind::Block)
: name(move(name))
, local_variables(move(variables))
, is_function_frame(kind == LocalFrameKind::FunctionOrGlobal)
{
}
DeprecatedString name;
HashMap<DeprecatedString, RefPtr<AST::Value>> local_variables;
bool is_function_frame;
};
struct Frame {
Frame(Vector<NonnullOwnPtr<LocalFrame>>& frames, LocalFrame const& frame)
: frames(frames)
, frame(frame)
{
}
~Frame();
void leak_frame() { should_destroy_frame = false; }
private:
Vector<NonnullOwnPtr<LocalFrame>>& frames;
LocalFrame const& frame;
bool should_destroy_frame { true };
};
[[nodiscard]] Frame push_frame(DeprecatedString name, LocalFrameKind = LocalFrameKind::Block);
void pop_frame();
struct Promise {
struct Data {
struct Unveil {
DeprecatedString path;
DeprecatedString access;
};
DeprecatedString exec_promises;
Vector<Unveil> unveils;
} data;
IntrusiveListNode<Promise> node;
using List = IntrusiveList<&Promise::node>;
};
struct ScopedPromise {
ScopedPromise(Promise::List& promises, Promise&& promise)
: promises(promises)
, promise(move(promise))
{
promises.append(this->promise);
}
~ScopedPromise()
{
promises.remove(promise);
}
Promise::List& promises;
Promise promise;
};
[[nodiscard]] ScopedPromise promise(Promise::Data data)
{
return { m_active_promises, { move(data), {} } };
}
enum class EscapeMode {
Bareword,
SingleQuotedString,
DoubleQuotedString,
};
static DeprecatedString escape_token_for_double_quotes(StringView token);
static DeprecatedString escape_token_for_single_quotes(StringView token);
static DeprecatedString escape_token(StringView token, EscapeMode = EscapeMode::Bareword);
static DeprecatedString escape_token(Utf32View token, EscapeMode = EscapeMode::Bareword);
static DeprecatedString unescape_token(StringView token);
enum class SpecialCharacterEscapeMode {
Untouched,
Escaped,
QuotedAsEscape,
QuotedAsHex,
};
static SpecialCharacterEscapeMode special_character_escape_mode(u32 c, EscapeMode);
static bool is_glob(StringView);
static Vector<StringView> split_path(StringView);
enum class ExecutableOnly {
Yes,
No
};
ErrorOr<void> highlight(Line::Editor&) const;
Vector<Line::CompletionSuggestion> complete();
Vector<Line::CompletionSuggestion> complete(StringView);
Vector<Line::CompletionSuggestion> complete_program_name(StringView, size_t offset, EscapeMode = EscapeMode::Bareword);
Vector<Line::CompletionSuggestion> complete_variable(StringView, size_t offset);
Vector<Line::CompletionSuggestion> complete_user(StringView, size_t offset);
Vector<Line::CompletionSuggestion> complete_immediate_function_name(StringView, size_t offset);
Vector<Line::CompletionSuggestion> complete_path(StringView base, StringView, size_t offset, ExecutableOnly executable_only, AST::Node const* command_node, AST::Node const*, EscapeMode = EscapeMode::Bareword);
Vector<Line::CompletionSuggestion> complete_option(StringView, StringView, size_t offset, AST::Node const* command_node, AST::Node const*);
ErrorOr<Vector<Line::CompletionSuggestion>> complete_via_program_itself(size_t offset, AST::Node const* command_node, AST::Node const*, EscapeMode escape_mode, StringView known_program_name);
void restore_ios();
u64 find_last_job_id() const;
Job* find_job(u64 id, bool is_pid = false);
Job* current_job() const { return m_current_job; }
void kill_job(Job const*, int sig);
DeprecatedString get_history_path();
void print_path(StringView path);
void cache_path();
bool read_single_line();
void notify_child_event();
bool posix_mode() const { return m_in_posix_mode; }
struct termios termios;
struct termios default_termios;
bool was_interrupted { false };
bool was_resized { false };
DeprecatedString cwd;
DeprecatedString username;
DeprecatedString home;
constexpr static auto TTYNameSize = 32;
constexpr static auto HostNameSize = 64;
char ttyname[TTYNameSize];
char hostname[HostNameSize];
uid_t uid;
Optional<int> last_return_code;
Vector<DeprecatedString> directory_stack;
CircularQueue<DeprecatedString, 8> cd_history; // FIXME: have a configurable cd history length
HashMap<u64, NonnullRefPtr<Job>> jobs;
Vector<RunnablePath, 256> cached_path;
DeprecatedString current_script;
enum ShellEventType {
ReadLine,
};
enum class ShellError {
None,
InternalControlFlowBreak,
InternalControlFlowContinue,
InternalControlFlowInterrupted,
InternalControlFlowKilled,
EvaluatedSyntaxError,
NonExhaustiveMatchRules,
InvalidGlobError,
InvalidSliceContentsError,
OpenFailure,
OutOfMemory,
LaunchError,
PipeFailure,
WriteFailure,
};
void raise_error(ShellError kind, DeprecatedString description, Optional<AST::Position> position = {})
{
m_error = kind;
m_error_description = move(description);
if (m_source_position.has_value() && position.has_value())
m_source_position.value().position = position.release_value();
}
bool has_error(ShellError err) const { return m_error == err; }
bool has_any_error() const { return !has_error(ShellError::None); }
DeprecatedString const& error_description() const { return m_error_description; }
ShellError take_error()
{
auto err = m_error;
m_error = ShellError::None;
m_error_description = {};
return err;
}
void possibly_print_error() const;
static bool is_control_flow(ShellError error)
{
switch (error) {
case ShellError::InternalControlFlowBreak:
case ShellError::InternalControlFlowContinue:
case ShellError::InternalControlFlowInterrupted:
case ShellError::InternalControlFlowKilled:
return true;
default:
return false;
}
}
#define __ENUMERATE_SHELL_OPTION(name, default_, description) \
bool name { default_ };
struct Options {
ENUMERATE_SHELL_OPTIONS();
} options;
#undef __ENUMERATE_SHELL_OPTION
private:
Shell(Line::Editor&, bool attempt_interactive, bool posix_mode = false);
Shell();
virtual ~Shell() override;
void destroy();
void initialize(bool attempt_interactive);
RefPtr<AST::Node> parse(StringView, bool interactive = false, bool as_command = true) const;
void timer_event(Core::TimerEvent&) override;
bool is_allowed_to_modify_termios(const AST::Command&) const;
void bring_cursor_to_beginning_of_a_line() const;
Optional<int> resolve_job_spec(StringView);
void add_entry_to_cache(RunnablePath const&);
void remove_entry_from_cache(StringView);
void stop_all_jobs();
Job* m_current_job { nullptr };
LocalFrame* find_frame_containing_local_variable(StringView name);
LocalFrame const* find_frame_containing_local_variable(StringView name) const
{
return const_cast<Shell*>(this)->find_frame_containing_local_variable(name);
}
void run_tail(RefPtr<Job>);
void run_tail(const AST::Command&, const AST::NodeWithAction&, int head_exit_code);
[[noreturn]] void execute_process(Vector<char const*>&& argv);
ErrorOr<void> execute_process(Span<StringView> argv);
virtual void custom_event(Core::CustomEvent&) override;
#define __ENUMERATE_SHELL_IMMEDIATE_FUNCTION(name) \
ErrorOr<RefPtr<AST::Node>> immediate_##name(AST::ImmediateExpression& invoking_node, Vector<NonnullRefPtr<AST::Node>> const&);
ENUMERATE_SHELL_IMMEDIATE_FUNCTIONS();
#undef __ENUMERATE_SHELL_IMMEDIATE_FUNCTION
ErrorOr<RefPtr<AST::Node>> immediate_length_impl(AST::ImmediateExpression& invoking_node, Vector<NonnullRefPtr<AST::Node>> const&, bool across);
#define __ENUMERATE_SHELL_BUILTIN(builtin, _mode) \
ErrorOr<int> builtin_##builtin(Main::Arguments);
ENUMERATE_SHELL_BUILTINS();
#undef __ENUMERATE_SHELL_BUILTIN
static constexpr Array builtin_names = {
#define __ENUMERATE_SHELL_BUILTIN(builtin, _mode) #builtin##sv,
ENUMERATE_SHELL_BUILTINS()
#undef __ENUMERATE_SHELL_BUILTIN
"."sv, // Needs to be aliased to "source" in POSIX mode.
// clang-format off
// Clang-format does not properly indent this, it gives it 4 spaces too few.
":"sv, // POSIX-y name for "noop".
// clang-format on
};
bool m_should_ignore_jobs_on_next_exit { false };
pid_t m_pid { 0 };
struct ShellFunction {
DeprecatedString name;
Vector<DeprecatedString> arguments;
RefPtr<AST::Node> body;
};
HashMap<DeprecatedString, ShellFunction> m_functions;
Vector<NonnullOwnPtr<LocalFrame>> m_local_frames;
Promise::List m_active_promises;
Vector<NonnullRefPtr<AST::Redirection>> m_global_redirections;
HashMap<DeprecatedString, DeprecatedString> m_aliases;
bool m_is_interactive { true };
bool m_is_subshell { false };
bool m_should_reinstall_signal_handlers { true };
bool m_in_posix_mode { false };
ShellError m_error { ShellError::None };
DeprecatedString m_error_description;
Optional<SourcePosition> m_source_position;
bool m_should_format_live { false };
RefPtr<Line::Editor> m_editor;
bool m_default_constructed { false };
mutable bool m_last_continuation_state { false }; // false == not needed.
Optional<size_t> m_history_autosave_time;
StackInfo m_completion_stack_info;
};
[[maybe_unused]] static constexpr bool is_word_character(char c)
{
return c == '_' || (c <= 'Z' && c >= 'A') || (c <= 'z' && c >= 'a') || (c <= '9' && c >= '0');
}
inline size_t find_offset_into_node(StringView unescaped_text, size_t escaped_offset, Shell::EscapeMode escape_mode)
{
size_t unescaped_offset = 0;
size_t offset = 0;
auto do_find_offset = [&](auto& unescaped_text) {
for (auto c : unescaped_text) {
if (offset == escaped_offset)
return unescaped_offset;
switch (Shell::special_character_escape_mode(c, escape_mode)) {
case Shell::SpecialCharacterEscapeMode::Untouched:
break;
case Shell::SpecialCharacterEscapeMode::Escaped:
++offset; // X -> \X
break;
case Shell::SpecialCharacterEscapeMode::QuotedAsEscape:
switch (escape_mode) {
case Shell::EscapeMode::Bareword:
offset += 3; // X -> "\Y"
break;
case Shell::EscapeMode::SingleQuotedString:
offset += 5; // X -> '"\Y"'
break;
case Shell::EscapeMode::DoubleQuotedString:
offset += 1; // X -> \Y
break;
}
break;
case Shell::SpecialCharacterEscapeMode::QuotedAsHex:
switch (escape_mode) {
case Shell::EscapeMode::Bareword:
offset += 2; // X -> "\..."
break;
case Shell::EscapeMode::SingleQuotedString:
offset += 4; // X -> '"\..."'
break;
case Shell::EscapeMode::DoubleQuotedString:
// X -> \...
break;
}
if (c > NumericLimits<u8>::max())
offset += 8; // X -> "\uhhhhhhhh"
else
offset += 3; // X -> "\xhh"
break;
}
++offset;
++unescaped_offset;
}
return unescaped_offset;
};
Utf8View view { unescaped_text };
if (view.validate())
return do_find_offset(view);
return do_find_offset(unescaped_text);
}
}
namespace AK {
template<>
struct Traits<Shell::Shell::RunnablePath> : public GenericTraits<Shell::Shell::RunnablePath> {
static constexpr bool is_trivial() { return false; }
static bool equals(Shell::Shell::RunnablePath const& self, Shell::Shell::RunnablePath const& other)
{
return self == other;
}
static bool equals(Shell::Shell::RunnablePath const& self, StringView other)
{
return self.path == other;
}
static bool equals(Shell::Shell::RunnablePath const& self, DeprecatedString const& other)
{
return self.path == other;
}
};
}