ladybird/Shell/Parser.h
Andreas Kling ed90d39cd7 Shell: Allow empty tokens if enclosed in single or double quotes
Previously the shell parser would discard empty tokens. We now allow
them when they are enclosed in quotes (either '' or "")

This means that a command like _echo ""_ will actually pass an empty
string to /bin/echo in argv[1] now.
2020-01-25 12:16:45 +01:00

93 lines
2.6 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.
*/
#pragma once
#include <AK/String.h>
#include <AK/Vector.h>
struct Redirection {
enum Type {
Pipe,
FileWrite,
FileWriteAppend,
FileRead,
};
Type type;
int fd { -1 };
int rewire_fd { -1 };
String path {};
};
struct Rewiring {
int fd { -1 };
int rewire_fd { -1 };
};
struct Subcommand {
Vector<String> args;
Vector<Redirection> redirections;
Vector<Rewiring> rewirings;
};
struct Command {
Vector<Subcommand> subcommands;
};
class Parser {
public:
explicit Parser(const String& input)
: m_input(input)
{
}
Vector<Command> parse();
private:
enum class AllowEmptyToken { No, Yes };
void commit_token(AllowEmptyToken = AllowEmptyToken::No);
void commit_subcommand();
void commit_command();
void do_pipe();
void begin_redirect_read(int fd);
void begin_redirect_write(int fd);
enum State {
Free,
InSingleQuotes,
InDoubleQuotes,
InWriteAppendOrRedirectionPath,
InRedirectionPath,
};
State m_state { Free };
String m_input;
Vector<Command> m_commands;
Vector<Subcommand> m_subcommands;
Vector<String> m_tokens;
Vector<Redirection> m_redirections;
Vector<char> m_token;
};