path: root/src/terminal.c

/* vi:set ts=8 sts=4 sw=4 noet:
 *
 * VIM - Vi IMproved	by Bram Moolenaar
 *
 * Do ":help uganda"  in Vim to read copying and usage conditions.
 * Do ":help credits" in Vim to see a list of people who contributed.
 * See README.txt for an overview of the Vim source code.
 */

/*
 * Terminal window support, see ":help :terminal".
 *
 * There are three parts:
 * 1. Generic code for all systems.
 * 2. The MS-Windows implementation.
 *    Uses a hidden console for the terminal emulator.
 * 3. The Unix-like implementation.
 *    Uses libvterm for the terminal emulator.
 *
 * When a terminal window is opened, a job is started that will be connected to
 * the terminal emulator.
 *
 * If the terminal window has keyboard focus, typed keys are converted to the
 * terminal encoding and writting to the job over a channel.
 *
 * If the job produces output, it is written to the terminal emulator.  The
 * terminal emulator invokes callbacks when its screen content changes.  The
 * line range is stored in tl_dirty_row_start and tl_dirty_row_end.  Once in a
 * while, if the terminal window is visible, the screen contents is drawn.
 *
 * TODO:
 * - set buffer options to be scratch, hidden, nomodifiable, etc.
 * - set buffer name to command, add (1) to avoid duplicates.
 * - If [command] is not given the 'shell' option is used.
 * - Add a scrollback buffer (contains lines to scroll off the top).
 *   Can use the buf_T lines, store attributes somewhere else?
 * - When the job ends:
 *   - Write "-- JOB ENDED --" in the terminal.
 *   - Put the terminal contents in the scrollback buffer.
 *   - Free the terminal emulator.
 *   - Display the scrollback buffer (but with attributes).
 *     Make the buffer not modifiable, drop attributes when making changes.
 * - when closing window and job has not ended, make terminal hidden?
 * - Use a pty for I/O with the job.
 * - Windows implementation:
 *   (WiP): https://github.com/mattn/vim/tree/terminal
 *	src/os_win32.c  mch_open_terminal()
 *   Using winpty ?
 * - use win_del_lines() to make scroll-up efficient.
 * - command line completion for :terminal
 * - support fixed size when 'termsize' is "rowsXcols".
 * - support minimal size when 'termsize' is "rows*cols".
 * - support minimal size when 'termsize' is empty.
 * - implement ":buf {term-buf-name}"
 * - implement term_list()			list of buffers with a terminal
 * - implement term_getsize(buf)
 * - implement term_setsize(buf)
 * - implement term_sendkeys(buf, keys)		send keystrokes to a terminal
 * - implement term_wait(buf)			wait for screen to be updated
 * - implement term_scrape(buf, row)		inspect terminal screen
 * - implement term_open(command, options)	open terminal window
 * - implement term_getjob(buf)
 * - implement 'termkey'
 */

#include "vim.h"

#ifdef FEAT_TERMINAL

#ifdef WIN3264
/* MS-Windows: use a native console. */
#else
/* Unix-like: use libvterm. */
# include "libvterm/include/vterm.h"
#endif

/* typedef term_T in structs.h */
struct terminal_S {
    term_T	*tl_next;

#ifdef WIN3264
    /* console handle? */
#else
    VTerm	*tl_vterm;
#endif
    job_T	*tl_job;
    buf_T	*tl_buffer;

    /* Range of screen rows to update.  Zero based. */
    int		tl_dirty_row_start; /* -1 if nothing dirty */
    int		tl_dirty_row_end;   /* row below last one to update */

    pos_T	tl_cursor;
};

#define MAX_ROW 999999	    /* used for tl_dirty_row_end to update all rows */
#define KEY_BUF_LEN 200

/* Functions implemented for MS-Windows and Unix-like systems. */
static int term_init(term_T *term, int rows, int cols);
static void term_free(term_T *term);
static void term_write_job_output(term_T *term, char_u *msg, size_t len);
static int term_convert_key(int c, char *buf);
static void term_update_lines(win_T *wp);

/*
 * List of all active terminals.
 */
static term_T *first_term = NULL;

/**************************************
 * 1. Generic code for all systems.
 */

/*
 * ":terminal": open a terminal window and execute a job in it.
 */
    void
ex_terminal(exarg_T *eap)
{
    int		rows;
    int		cols;
    exarg_T	split_ea;
    win_T	*old_curwin = curwin;
    typval_T	argvars[2];
    term_T	*term;
    jobopt_T	opt;

    if (check_restricted() || check_secure())
	return;

    term = (term_T *)alloc_clear(sizeof(term_T));
    if (term == NULL)
	return;
    term->tl_dirty_row_end = MAX_ROW;

    /* Open a new window or tab. */
    vim_memset(&split_ea, 0, sizeof(split_ea));
    split_ea.cmdidx = CMD_new;
    split_ea.cmd = (char_u *)"new";
    split_ea.arg = (char_u *)"";
    ex_splitview(&split_ea);
    if (curwin == old_curwin)
    {
	/* split failed */
	vim_free(term);
	return;
    }
    term->tl_buffer = curbuf;

    curbuf->b_term = term;
    term->tl_next = first_term;
    first_term = term;

    /* TODO: set buffer type, hidden, etc. */

    if (*curwin->w_p_tms != NUL)
    {
	char_u *p = vim_strchr(curwin->w_p_tms, 'x') + 1;

	rows = atoi((char *)curwin->w_p_tms);
	cols = atoi((char *)p);
	/* TODO: resize window if possible. */
    }
    else
    {
	rows = curwin->w_height;
	cols = curwin->w_width;
    }

    if (term_init(term, rows, cols) == OK)
    {
	argvars[0].v_type = VAR_STRING;
	argvars[0].vval.v_string = eap->arg;

	clear_job_options(&opt);
	opt.jo_mode = MODE_RAW;
	opt.jo_out_mode = MODE_RAW;
	opt.jo_err_mode = MODE_RAW;
	opt.jo_set = JO_MODE | JO_OUT_MODE | JO_ERR_MODE;
	opt.jo_io[PART_OUT] = JIO_BUFFER;
	opt.jo_io[PART_ERR] = JIO_BUFFER;
	opt.jo_set |= JO_OUT_IO + (JO_OUT_IO << (PART_ERR - PART_OUT));
	opt.jo_io_buf[PART_OUT] = curbuf->b_fnum;
	opt.jo_io_buf[PART_ERR] = curbuf->b_fnum;
	opt.jo_set |= JO_OUT_BUF + (JO_OUT_BUF << (PART_ERR - PART_OUT));

	term->tl_job = job_start(argvars, &opt);
    }

    if (term->tl_job == NULL)
	/* Wiping out the buffer will also close the window. */
	do_buffer(DOBUF_WIPE, DOBUF_CURRENT, FORWARD, 0, TRUE);

    /* TODO: Setup pty, see mch_call_shell(). */
}

/*
 * Free a terminal and everything it refers to.
 * Kills the job if there is one.
 * Called when wiping out a buffer.
 */
    void
free_terminal(term_T *term)
{
    term_T	*tp;

    if (term == NULL)
	return;
    if (first_term == term)
	first_term = term->tl_next;
    else
	for (tp = first_term; tp->tl_next != NULL; tp = tp->tl_next)
	    if (tp->tl_next == term)
	    {
		tp->tl_next = term->tl_next;
		break;
	    }

    if (term->tl_job != NULL)
    {
	if (term->tl_job->jv_status != JOB_ENDED)
	    job_stop(term->tl_job, NULL, "kill");
	job_unref(term->tl_job);
    }

    term_free(term);
    vim_free(term);
}

/*
 * Invoked when "msg" output from a job was received.  Write it to the terminal
 * of "buffer".
 */
    void
write_to_term(buf_T *buffer, char_u *msg, channel_T *channel)
{
    size_t	len = STRLEN(msg);
    term_T	*term = buffer->b_term;

    ch_logn(channel, "writing %d bytes to terminal", (int)len);
    term_write_job_output(term, msg, len);

    /* TODO: only update once in a while. */
    update_screen(0);
    setcursor();
    out_flush();
}

/*
 * Wait for input and send it to the job.
 * Return when the start of a CTRL-W command is typed or anything else that
 * should be handled as a Normal mode command.
 */
    void
terminal_loop(void)
{
    char	buf[KEY_BUF_LEN];
    int		c;
    size_t	len;
    static int	mouse_was_outside = FALSE;
    int		dragging_outside = FALSE;

    for (;;)
    {
	/* TODO: skip screen update when handling a sequence of keys. */
	update_screen(0);