util.c

This version of dialog, formerly known as cdialog is based on the Debian package for dialog 0.9a (se

/*
 *  $Id: util.c,v 1.118 2003/12/01 00:32:44 tom Exp $
 *
 *  util.c -- miscellaneous utilities for dialog
 *
 *  AUTHOR: Savio Lam ([e-mail])
 *     and: Thomas E. Dickey
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include "dialog.h"

#include <stdarg.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <time.h>

#ifdef NCURSES_VERSION
#if defined(HAVE_NCURSESW_TERM_H)
#include <ncursesw/term.h>
#elif defined(HAVE_NCURSES_TERM_H)
#include <ncurses/term.h>
#else
#include <term.h>
#endif
#endif

#ifndef O_BINARY
#define O_BINARY 0
#endif

#ifndef S_IRUSR
#define S_IRUSR 0400
#endif

#ifndef S_IWUSR
#define S_IWUSR 0200
#endif

#ifndef DIALOG_TMPDIR
#define DIALOG_TMPDIR NULL
#endif

#define LOCK_PERMITS (S_IRUSR | S_IWUSR)
#define LOCK_TIMEOUT 10		/* timeout for locking, in seconds */

/* globals */
DIALOG_STATE dialog_state;
DIALOG_VARS dialog_vars;

#define concat(a,b) a##b

#ifdef HAVE_RC_FILE
#define RC_DATA(name,comment) , #name "_color", comment " color"
#else
#define RC_DATA(name,comment)	/*nothing */
#endif

#ifdef HAVE_COLOR
#include <colors.h>
#define COLOR_DATA(upr) , concat(upr,_FG), concat(upr,_BG), concat(upr,_HL)
#else
#define COLOR_DATA(upr)		/*nothing */
#endif

#define DATA(atr,upr,lwr,cmt) { atr COLOR_DATA(upr) RC_DATA(lwr,cmt) }

/*
 * Table of color and attribute values, default is for mono display.
 */
/* *INDENT-OFF* */
DIALOG_COLORS dlg_color_table[] =
{
    DATA(A_NORMAL,	SCREEN,			screen, "Screen"),
    DATA(A_NORMAL,	SHADOW,			shadow, "Shadow"),
    DATA(A_REVERSE,	DIALOG,			dialog, "Dialog box"),
    DATA(A_REVERSE,	TITLE,			title, "Dialog box title"),
    DATA(A_REVERSE,	BORDER,			border, "Dialog box border"),
    DATA(A_BOLD,	BUTTON_ACTIVE,		button_active, "Active button"),
    DATA(A_DIM,		BUTTON_INACTIVE,	button_inactive, "Inactive button"),
    DATA(A_UNDERLINE,	BUTTON_KEY_ACTIVE,	button_key_active, "Active button key"),
    DATA(A_UNDERLINE,	BUTTON_KEY_INACTIVE,	button_key_inactive, "Inactive button key"),
    DATA(A_NORMAL,	BUTTON_LABEL_ACTIVE,	button_label_active, "Active button label"),
    DATA(A_NORMAL,	BUTTON_LABEL_INACTIVE,	button_label_inactive, "Inactive button label"),
    DATA(A_REVERSE,	INPUTBOX,		inputbox, "Input box"),
    DATA(A_REVERSE,	INPUTBOX_BORDER,	inputbox_border, "Input box border"),
    DATA(A_REVERSE,	SEARCHBOX,		searchbox, "Search box"),
    DATA(A_REVERSE,	SEARCHBOX_TITLE,	searchbox_title, "Search box title"),
    DATA(A_REVERSE,	SEARCHBOX_BORDER,	searchbox_border, "Search box border"),
    DATA(A_REVERSE,	POSITION_INDICATOR,	position_indicator, "File position indicator"),
    DATA(A_REVERSE,	MENUBOX,		menubox, "Menu box"),
    DATA(A_REVERSE,	MENUBOX_BORDER,		menubox_border, "Menu box border"),
    DATA(A_REVERSE,	ITEM,			item, "Item"),
    DATA(A_NORMAL,	ITEM_SELECTED,		item_selected, "Selected item"),
    DATA(A_REVERSE,	TAG,			tag, "Tag"),
    DATA(A_REVERSE,	TAG_SELECTED,		tag_selected, "Selected tag"),
    DATA(A_NORMAL,	TAG_KEY,		tag_key, "Tag key"),
    DATA(A_BOLD,	TAG_KEY_SELECTED,	tag_key_selected, "Selected tag key"),
    DATA(A_REVERSE,	CHECK,			check, "Check box"),
    DATA(A_REVERSE,	CHECK_SELECTED,		check_selected, "Selected check box"),
    DATA(A_REVERSE,	UARROW,			uarrow, "Up arrow"),
    DATA(A_REVERSE,	DARROW,			darrow, "Down arrow"),
    DATA(A_NORMAL,	ITEMHELP,		itemhelp, "Item help-text"),
    DATA(A_BOLD,	FORM_ACTIVE_TEXT,	form_active_text, "Active form text"),
    DATA(A_REVERSE,	FORM_TEXT,		form_text, "Form text"),
};
/* *INDENT-ON* */

/*
 * Display background title if it exists ...
 */
void
dlg_put_backtitle(void)
{
    int i;

    if (dialog_vars.backtitle != NULL) {
	chtype attr = A_NORMAL;

	wattrset(stdscr, screen_attr);
	(void) wmove(stdscr, 0, 1);
	dlg_print_text(stdscr, dialog_vars.backtitle, COLS - 2, &attr);
	for (i = 0; i < COLS - (int) strlen(dialog_vars.backtitle); i++)
	    (void) waddch(stdscr, ' ');
	(void) wmove(stdscr, 1, 1);
	for (i = 0; i < COLS - 2; i++)
	    (void) waddch(stdscr, ACS_HLINE);
    }

    (void) wnoutrefresh(stdscr);
}

/*
 * Set window to attribute 'attr'.  There are more efficient ways to do this,
 * but will not work on older/buggy ncurses versions.
 */
void
dlg_attr_clear(WINDOW *win, int height, int width, chtype attr)
{
    int i, j;

    wattrset(win, attr);
    for (i = 0; i < height; i++) {
	(void) wmove(win, i, 0);
	for (j = 0; j < width; j++)
	    (void) waddch(win, ' ');
    }
    (void) touchwin(win);
}

void
dlg_clear(void)
{
    dlg_attr_clear(stdscr, LINES, COLS, screen_attr);
}

#define isprivate(s) ((s) != 0 && strstr(s, "\033[?") != 0)

#define TTY_DEVICE "/dev/tty"

/*
 * If $DIALOG_TTY exists, allow the program to try to open the terminal
 * directly when stdout is redirected.  By default we require the "--stdout"
 * option to be given, but some scripts were written making use of the
 * behavior of dialog which tried opening the terminal anyway. 
 */
static char *
dialog_tty(void)
{
    char *result = getenv("DIALOG_TTY");
    if (result != 0 && atoi(result))
	result = 0;
    return result;
}

/*
 * Open the terminal directly.  If one of stdin, stdout or stderr really points
 * to a tty, use it.  Otherwise give up and open /dev/tty.
 */
static int
open_terminal(char **result, int mode)
{
    const char *device = TTY_DEVICE;
    if (!isatty(fileno(stderr))
	|| (device = ttyname(fileno(stderr))) == 0) {
	if (!isatty(fileno(stdout))
	    || (device = ttyname(fileno(stdout))) == 0) {
	    if (!isatty(fileno(stdin))
		|| (device = ttyname(fileno(stdin))) == 0) {
		device = TTY_DEVICE;
	    }
	}
    }
    *result = dlg_strclone(device);
    return open(device, mode);
}

/*
 * Do some initialization for dialog.
 *
 * 'input' is the real tty input of dialog.  Usually it is stdin, but if
 * --input-fd option is used, it may be anything.
 *
 * 'output' is where dialog will send its result.  Usually it is stderr, but
 * if --stdout or --output-fd is used, it may be anything.  We are concerned
 * mainly with the case where it happens to be the same as stdout.
 */
void
init_dialog(FILE *input, FILE *output)
{
    int fd1, fd2;
    char *device = 0;

    dialog_state.output = output;
    dialog_state.tab_len = TAB_LEN;
    dialog_state.aspect_ratio = DEFAULT_ASPECT_RATIO;
#ifdef HAVE_COLOR
    dialog_state.use_colors = USE_COLORS;	/* use colors by default? */
    dialog_state.use_shadow = USE_SHADOW;	/* shadow dialog boxes by default? */
#endif

#ifdef HAVE_RC_FILE
    if (dlg_parse_rc() == -1)	/* Read the configuration file */
	dlg_exiterr("init_dialog: dlg_parse_rc");
#endif

    /*
     * Some widgets (such as gauge) may read from the standard input.  Pipes
     * only connect stdout/stdin, so there is not much choice.  But reading a
     * pipe would get in the way of curses' normal reading stdin for getch.
     *
     * As in the --stdout (see below), reopening the terminal does not always
     * work properly.  dialog provides a --pipe-fd option for this purpose.  We
     * test that case first (differing fileno's for input/stdin).  If the
     * fileno's are equal, but we're not reading from a tty, see if we can open
     * /dev/tty.
     */
    dialog_state.pipe_input = stdin;
    if (fileno(input) != fileno(stdin)) {
	if ((fd1 = dup(fileno(input))) >= 0
	    && (fd2 = dup(fileno(stdin))) >= 0) {
	    *stdin = *fdopen(fd1, "r");
	    dialog_state.pipe_input = fdopen(fd2, "r");
	    if (fileno(stdin) != 0)	/* some functions may read fd #0 */
		(void) dup2(fileno(stdin), 0);
	} else
	    dlg_exiterr("cannot open tty-input");
    } else if (!isatty(fileno(stdin))) {
	if ((fd1 = open_terminal(&device, O_RDONLY)) >= 0
	    && (fd2 = dup(fileno(stdin))) >= 0) {
	    dialog_state.pipe_input = fdopen(fd2, "r");
	    *stdin = *freopen(device, "r", stdin);
	    if (fileno(stdin) != 0)	/* some functions may read fd #0 */
		(void) dup2(fileno(stdin), 0);
	}
	free(device);
    }

    /*
     * If stdout is not a tty and dialog is called with the --stdout option, we
     * have to provide for a way to write to the screen.
     *
     * The curses library normally writes its output to stdout, leaving stderr
     * free for scripting.  Scripts are simpler when stdout is redirected.  The
     * newterm function is useful; it allows us to specify where the output
     * goes.  Reopening the terminal is not portable since several
     * configurations do not allow this to work properly:
     *
     * a) some getty implementations (and possibly broken tty drivers, e.g., on
     *    HPUX 10 and 11) cause stdin to act as if it is still in cooked mode
     *    even though results from ioctl's state that it is successfully
     *    altered to raw mode.  Broken is the proper term.
     *
     * b) the user may not have permissions on the device, e.g., if one su's
     *    from the login user to another non-privileged user.
     */
    if (!isatty(fileno(stdout))
	&& (fileno(stdout) == fileno(output) || dialog_tty())) {
	if ((fd1 = open_terminal(&device, O_WRONLY)) >= 0
	    && (dialog_state.screen_output = fdopen(fd1, "w")) != 0) {
	    if (newterm(NULL, dialog_state.screen_output, stdin) == 0) {
		dlg_exiterr("cannot initialize curses");
	    }
	    free(device);
	} else {
	    dlg_exiterr("cannot open tty-output");
	}
    } else {
	dialog_state.screen_output = stdout;
	(void) initscr();
    }
#ifdef NCURSES_VERSION
    /*
     * Cancel xterm's alternate-screen mode.
     */
    if ((dialog_state.screen_output != stdout || isatty(fileno(dialog_state.screen_output)))
	&& key_mouse != 0	/* xterm and kindred */
	&& isprivate(enter_ca_mode)
	&& isprivate(exit_ca_mode)) {
	/*
	 * initscr() or newterm() already did putp(enter_ca_mode) as a side
	 * effect of initializing the screen.  It would be nice to not even
	 * do that, but we do not really have access to the correct copy of
	 * the terminfo description until those functions have been invoked.
	 */
	(void) putp(exit_ca_mode);
	(void) putp(clear_screen);
	/*
	 * Prevent ncurses from switching "back" to the normal screen when
	 * exiting from dialog.  That would move the cursor to the original
	 * location saved in xterm.  Normally curses sets the cursor position
	 * to the first line after the display, but the alternate screen
	 * switching is done after that point.
	 *
	 * Cancelling the strings altogether also works around the buggy
	 * implementation of alternate-screen in rxvt, etc., which clear
	 * more of the display than they should.
	 */
	enter_ca_mode = 0;
	exit_ca_mode = 0;
    }
#endif
    (void) keypad(stdscr, TRUE);
    (void) cbreak();
    (void) noecho();
    mouse_open();
    dialog_state.screen_initialized = 1;

#ifdef HAVE_COLOR
    if (dialog_state.use_colors || dialog_state.use_shadow)
	dlg_color_setup();	/* Set up colors */
#endif

    /* Set screen to screen attribute */
    dlg_clear();
}

#ifdef HAVE_COLOR
static int defined_colors = 0;
/*
 * Setup for color display
 */
void
dlg_color_setup(void)
{
    unsigned i;

    if (has_colors()) {		/* Terminal supports color? */
	(void) start_color();

	for (i = 0; i < sizeof(dlg_color_table) /
	     sizeof(dlg_color_table[0]); i++) {

	    /* Initialize color pairs */
	    (void) init_pair(i + 1, dlg_color_table[i].fg,
			     dlg_color_table[i].bg);

	    /* Setup color attributes */
	    dlg_color_table[i].atr = C_ATTR(dlg_color_table[i].hilite, i + 1);
	}
	defined_colors = i + 1;
    }
}

int
dlg_color_count(void)
{
    return sizeof(dlg_color_table) / sizeof(dlg_color_table[0]);
}

/*
 * Reuse color pairs (they are limited), returning a COLOR_PAIR() value if we
 * have (or can) define a pair with the given color as foreground on the
 * window's defined background.
 */
static chtype
define_color(WINDOW *win, int foreground)
{
    chtype result = 0;
    chtype attrs = getattrs(win);
    int pair;
    short fg, bg, background;
    bool found = FALSE;

    if ((pair = PAIR_NUMBER(attrs)) != 0
	&& pair_content(pair, &fg, &bg) != ERR
	&& bg != foreground) {
	background = bg;
    } else {
	background = COLOR_BLACK;
    }

    for (pair = 0; pair < defined_colors; ++pair) {
	if (pair_content(pair, &fg, &bg) != ERR
	    && fg == foreground
	    && bg == background) {
	    result = COLOR_PAIR(pair);
	    found = TRUE;
	    break;
	}
    }
    if (!found && (defined_colors + 1) < COLOR_PAIRS) {
	pair = defined_colors++;
	(void) init_pair(pair, foreground, background);
	result = COLOR_PAIR(pair);
    }
    return result;
}
#endif

/*
 * End using dialog functions.
 */
void
end_dialog(void)
{
    if (dialog_state.screen_initialized) {
	dialog_state.screen_initialized = 0;
	mouse_close();
	(void) endwin();
	(void) fflush(stdout);
    }
}

#define isOurEscape(p) (((p)[0] == '\\') && ((p)[1] == 'Z') && ((p)[2] != 0))

static int
centered(int width, const char *string)
{
    int len = strlen(string);
    int left;
    int hide = 0;
    int n;

    if (dialog_vars.colors) {
	for (n = 0; n < len; ++n) {
	    if (isOurEscape(string + n)) {
		hide += 3;
	    }
	}
    }
    left = (width - (len - hide)) / 2 - 1;
    if (left < 0)
	left = 0;
    return left;
}

/*
 * Print up to 'len' bytes from 'text', optionally rendering our escape
 * sequence for attributes and color.
 */
void
dlg_print_text(WINDOW *win, const char *txt, int len, chtype *attr)
{
    while (len > 0 && (*txt != '\0')) {
	if (dialog_vars.colors) {
	    while (isOurEscape(txt)) {
		int code;

		txt += 2;
		switch (code = CharOf(*txt)) {
#ifdef HAVE_COLOR
		case '0':
		case '1':
		case '2':
		case '3':
		case '4':
		case '5':
		case '6':
		case '7':
		    *attr &= ~A_COLOR;
		    *attr |= define_color(win, code - '0');
		    break;
#endif
		case 'B':
		    *attr &= ~A_BOLD;
		    break;
		case 'b':
		    *attr = A_BOLD;
		    break;
		case 'R':
		    *attr &= ~A_REVERSE;
		    break;
		case 'r':
		    *attr = A_REVERSE;
		    break;
		case 'U':
		    *attr &= ~A_UNDERLINE;
		    break;
		case 'u':
		    *attr = A_UNDERLINE;
		    break;
		case 'n':
		    *attr = A_NORMAL;
		    break;
		}
		++txt;
	    }
	    if (*txt == '\n')
		break;
	}
	(void) waddch(win, CharOf(*txt++) | *attr);
	--len;
    }
}