ladybird/Shell/Parser.cpp
AnotherTest 77039e5354 Shell: Correctly complete paths in redirections
This commit allows the Shell to complete paths in redirections.
A closing quote is added if the path is an unclosed quote.
```
$ foo > "foob<tab>
$ foo > "foobar"
```
2020-05-30 00:36:51 +02:00

364 lines
12 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "Parser.h"
#include <ctype.h>
#include <stdio.h>
#include <unistd.h>
void Parser::commit_token(Token::Type type, AllowEmptyToken allow_empty)
{
if (allow_empty == AllowEmptyToken::No && m_token.is_empty())
return;
Token token { String::copy(m_token), m_position, m_token.size(), type };
if (state() == InRedirectionPath) {
m_redirections.last().path = move(token);
m_token.clear_with_capacity();
return;
}
m_tokens.append(token);
m_token.clear_with_capacity();
};
void Parser::commit_subcommand()
{
if (m_tokens.is_empty())
return;
m_subcommands.append({ move(m_tokens), move(m_redirections), {} });
}
void Parser::commit_command(Attributes attributes)
{
if (m_subcommands.is_empty())
return;
m_commands.append({ move(m_subcommands), attributes });
}
void Parser::do_pipe()
{
m_redirections.append({ Redirection::Pipe, STDOUT_FILENO });
commit_subcommand();
}
void Parser::begin_redirect_read(int fd)
{
m_redirections.append({ Redirection::FileRead, fd });
}
void Parser::begin_redirect_write(int fd)
{
m_redirections.append({ Redirection::FileWrite, fd });
}
bool Parser::in_state(State state) const
{
for (auto s : m_state_stack)
if (s == state)
return true;
return false;
}
Vector<Command> Parser::parse()
{
for (size_t i = 0; i < m_input.length(); ++i, m_position = i) {
char ch = m_input.characters()[i];
switch (state()) {
case State::Free:
if (ch == '#') {
commit_token(Token::Bare);
while (i < m_input.length()) {
ch = m_input.characters()[++i];
++m_position;
if (ch == '\n')
break;
m_token.append(ch);
}
commit_token(Token::Comment);
break;
}
if (ch == ' ') {
commit_token(Token::Bare);
break;
}
if (ch == ';') {
commit_token(Token::Special);
commit_subcommand();
commit_command();
break;
}
if (ch == '&') {
commit_token(Token::Special);
if (i + 1 >= m_input.length()) {
in_background:;
// Nothing interesting past this token, commit with InBackground
commit_subcommand();
commit_command(Attributes::InBackground);
break;
}
ch = m_input.characters()[++i];
++m_position;
if (ch == '&') {
// This is '&&', commit with ShortCircuit
commit_subcommand();
commit_command(Attributes::ShortCircuitOnFailure);
break;
}
--i;
--m_position;
goto in_background;
}
if (ch == '|') {
commit_token(Token::Special);
if (m_tokens.is_empty()) {
fprintf(stderr, "Syntax error: Nothing before pipe (|)\n");
return {};
}
do_pipe();
break;
}
if (ch == '>') {
commit_token(Token::Special);
begin_redirect_write(STDOUT_FILENO);
// Search for another > for append.
push_state(State::InWriteAppendOrRedirectionPath);
break;
}
if (ch == '<') {
commit_token(Token::Special);
begin_redirect_read(STDIN_FILENO);
push_state(State::InRedirectionPath);
break;
}
if (ch == '\\') {
if (i == m_input.length() - 1) {
fprintf(stderr, "Syntax error: Nothing to escape (\\)\n");
return {};
}
char next_ch = m_input.characters()[i + 1];
m_token.append(next_ch);
++i;
break;
}
if (ch == '\'') {
push_state(State::InSingleQuotes);
break;
}
if (ch == '\"') {
push_state(State::InDoubleQuotes);
break;
}
// redirection from zsh-style multi-digit fd, such as {10}>file
if (ch == '{') {
bool is_multi_fd_redirection = false;
size_t redir_end = i + 1;
while (redir_end < m_input.length()) {
char lookahead_ch = m_input.characters()[redir_end];
if (isdigit(lookahead_ch)) {
++redir_end;
continue;
}
if (lookahead_ch == '}' && redir_end + 1 != m_input.length()) {
// Disallow {}> and {}<
if (redir_end == i + 1)
break;
++redir_end;
if (m_input.characters()[redir_end] == '>' || m_input.characters()[redir_end] == '<')
is_multi_fd_redirection = true;
break;
}
break;
}
if (is_multi_fd_redirection) {
commit_token(Token::Special);
int fd = atoi(&m_input.characters()[i + 1]);
if (m_input.characters()[redir_end] == '>') {
begin_redirect_write(fd);
// Search for another > for append.
push_state(State::InWriteAppendOrRedirectionPath);
}
if (m_input.characters()[redir_end] == '<') {
begin_redirect_read(fd);
push_state(State::InRedirectionPath);
}
i = redir_end;
break;
}
}
if (isdigit(ch)) {
if (i != m_input.length() - 1) {
char next_ch = m_input.characters()[i + 1];
if (next_ch == '>') {
commit_token(Token::Special);
begin_redirect_write(ch - '0');
++i;
// Search for another > for append.
push_state(State::InWriteAppendOrRedirectionPath);
break;
}
if (next_ch == '<') {
commit_token(Token::Special);
begin_redirect_read(ch - '0');
++i;
push_state(State::InRedirectionPath);
break;
}
}
}
m_token.append(ch);
break;
case State::InWriteAppendOrRedirectionPath:
if (ch == '>') {
commit_token(Token::Special);
pop_state();
push_state(State::InRedirectionPath);
ASSERT(m_redirections.size());
m_redirections[m_redirections.size() - 1].type = Redirection::FileWriteAppend;
break;
}
// Not another > means that it's probably a path.
pop_state();
push_state(InRedirectionPath);
[[fallthrough]];
case State::InRedirectionPath:
if (ch == '<') {
commit_token(Token::Special);
begin_redirect_read(STDIN_FILENO);
pop_state();
push_state(State::InRedirectionPath);
break;
}
if (ch == '>') {
commit_token(Token::Special);
begin_redirect_read(STDOUT_FILENO);
pop_state();
push_state(State::InRedirectionPath);
break;
}
if (ch == '|') {
commit_token(Token::Special);
if (m_tokens.is_empty()) {
fprintf(stderr, "Syntax error: Nothing before pipe (|)\n");
return {};
}
do_pipe();
pop_state();
break;
}
if (ch == '"') {
push_state(State::InDoubleQuotes);
break;
}
if (ch == '\'') {
push_state(State::InSingleQuotes);
break;
}
if (ch == ' ')
break;
m_token.append(ch);
break;
case State::InSingleQuotes:
if (ch == '\'') {
if (!in_state(State::InRedirectionPath))
commit_token(Token::SingleQuoted, AllowEmptyToken::Yes);
pop_state();
break;
}
m_token.append(ch);
break;
case State::InDoubleQuotes:
if (ch == '\"') {
if (!in_state(State::InRedirectionPath))
commit_token(Token::DoubleQuoted, AllowEmptyToken::Yes);
pop_state();
break;
}
if (ch == '\\') {
if (i == m_input.length() - 1) {
fprintf(stderr, "Syntax error: Nothing to escape (\\)\n");
return {};
}
char next_ch = m_input.characters()[i + 1];
if (next_ch == '$' || next_ch == '`'
|| next_ch == '"' || next_ch == '\\') {
m_token.append(next_ch);
++i;
continue;
}
m_token.append('\\');
break;
}
m_token.append(ch);
break;
};
}
while (m_state_stack.size() > 1) {
if (state() == State::InDoubleQuotes) {
pop_state();
commit_token(Token::UnterminatedDoubleQuoted, AllowEmptyToken::Yes);
} else if (state() == State::InSingleQuotes) {
pop_state();
commit_token(Token::UnterminatedSingleQuoted, AllowEmptyToken::Yes);
} else {
commit_token(Token::Bare, AllowEmptyToken::No);
pop_state();
}
}
ASSERT(state() == State::Free);
commit_token(Token::Bare);
commit_subcommand();
commit_command();
if (!m_subcommands.is_empty()) {
for (auto& redirection : m_subcommands.last().redirections) {
if (redirection.type == Redirection::Pipe) {
fprintf(stderr, "Syntax error: Nothing after last pipe (|)\n");
return {};
}
}
}
return move(m_commands);
}