Shell/Parser.h


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#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:
    void commit_token();
    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;
};