textbox.c

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

/*
 *  $Id: textbox.c,v 1.45 2003/11/26 20:41:23 tom Exp $
 *
 *  textbox.c -- implements the text box
 *
 *  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"

typedef struct {
    DIALOG_CALLBACK obj;
    WINDOW *text;
    const char **buttons;
    int hscroll;
    char line[MAX_LEN + 1];
    int fd;
    int file_size;
    int fd_bytes_read;
    int bytes_read;
    int buffer_len;
    bool begin_reached;
    bool buffer_first;
    bool end_reached;
    int page_length;
    int in_buf;			/* index into buf[] */
    char *buf;
} MY_OBJ;

static long
lseek_obj(MY_OBJ * obj, long offset, int mode)
{
    long fpos;
    if ((fpos = lseek(obj->fd, offset, mode)) == -1) {
	switch (mode) {
	case SEEK_CUR:
	    dlg_exiterr("Cannot get file position");
	    break;
	case SEEK_END:
	    dlg_exiterr("Cannot seek to end of file");
	    break;
	case SEEK_SET:
	    dlg_exiterr("Cannot set file position to %ld", offset);
	    break;
	}
    }
    return fpos;
}

static long
ftell_obj(MY_OBJ * obj)
{
    return lseek_obj(obj, 0, SEEK_CUR);
}

static char *
xalloc(long size)
{
    char *result = malloc(size);
    assert_ptr(result, "xalloc");
    return result;
}

/*
 * read_high() substitutes read() for tab->spaces conversion
 *
 * buffer_len, fd_bytes_read, bytes_read are modified
 * buf is allocated
 *
 * fd_bytes_read is the effective number of bytes read from file
 * bytes_read is the length of buf, that can be different if tab_correct
 */
static void
read_high(MY_OBJ * obj, size_t size_read)
{
    char *buftab, ch;
    int i = 0, j, n, begin_line, tmpint;

    /* Allocate space for read buffer */
    buftab = xalloc(size_read + 1);

    if ((obj->fd_bytes_read = read(obj->fd, buftab, size_read)) != -1) {

	buftab[obj->fd_bytes_read] = '\0';	/* mark end of valid data */

	if (dialog_vars.tab_correct) {

	    /* calculate bytes_read by buftab and fd_bytes_read */
	    obj->bytes_read = begin_line = 0;
	    for (j = 0; j < obj->fd_bytes_read; j++)
		if (buftab[j] == TAB)
		    obj->bytes_read += dialog_state.tab_len
			- ((obj->bytes_read - begin_line)
			   % dialog_state.tab_len);
		else if (buftab[j] == '\n') {
		    obj->bytes_read++;
		    begin_line = obj->bytes_read;
		} else
		    obj->bytes_read++;

	    if (obj->bytes_read > obj->buffer_len) {
		if (obj->buffer_first)
		    obj->buffer_first = FALSE;	/* disp = 0 */
		else {
		    free(obj->buf);
		}

		obj->buffer_len = obj->bytes_read;

		/* Allocate space for read buffer */
		obj->buf = xalloc(obj->buffer_len + 1);
	    }

	} else {
	    if (obj->buffer_first) {
		obj->buffer_first = FALSE;

		/* Allocate space for read buffer */
		obj->buf = xalloc(size_read + 1);
	    }

	    obj->bytes_read = obj->fd_bytes_read;
	}

	j = 0;
	begin_line = 0;
	while (j < obj->fd_bytes_read)
	    if (((ch = buftab[j++]) == TAB) && (dialog_vars.tab_correct != 0)) {
		tmpint = dialog_state.tab_len
		    - ((i - begin_line) % dialog_state.tab_len);
		for (n = 0; n < tmpint; n++)
		    obj->buf[i++] = ' ';
	    } else {
		if (ch == '\n')
		    begin_line = i + 1;
		obj->buf[i++] = ch;
	    }

	obj->buf[i] = '\0';	/* mark end of valid data */

    }
    if (obj->bytes_read == -1)
	dlg_exiterr("Error reading file");
}

static int
tabize(MY_OBJ * obj, int val, int pos)
{
    long fpos;
    int i, count, begin_line;
    char *buftab;

    if (!dialog_vars.tab_correct)
	return val;

    fpos = ftell_obj(obj);

    lseek_obj(obj, fpos - obj->fd_bytes_read, SEEK_SET);

    /* Allocate space for read buffer */
    buftab = xalloc(val + 1);

    if ((read(obj->fd, buftab, val)) == -1)
	dlg_exiterr("Error reading file in tabize().");

    begin_line = count = 0;
    for (i = 0; i < val; i++) {
	if (pos && count >= val) {
	    count = i;		/* it's the retval */
	    break;
	}
	if (buftab[i] == TAB)
	    count += dialog_state.tab_len
		- ((count - begin_line) % dialog_state.tab_len);
	else if (buftab[i] == '\n') {
	    count++;
	    begin_line = count;
	} else
	    count++;
    }

    lseek_obj(obj, fpos, SEEK_SET);
    return count;
}
/*
 * Return current line of text.
 * 'page' should point to start of current line before calling, and will be
 * updated to point to start of next line.
 */
static char *
get_line(MY_OBJ * obj)
{
    int i = 0;
    long fpos;

    obj->end_reached = FALSE;
    while (obj->buf[obj->in_buf] != '\n') {
	if (obj->buf[obj->in_buf] == '\0') {	/* Either end of file or end of buffer reached */
	    fpos = ftell_obj(obj);

	    if (fpos < obj->file_size) {	/* Not end of file yet */
		/* We've reached end of buffer, but not end of file yet, so
		 * read next part of file into buffer
		 */
		read_high(obj, BUF_SIZE);
		obj->in_buf = 0;
	    } else {
		if (!obj->end_reached)
		    obj->end_reached = TRUE;
		break;
	    }
	} else if (i < MAX_LEN)
	    obj->line[i++] = obj->buf[obj->in_buf++];
	else {
	    if (i == MAX_LEN)	/* Truncate lines longer than MAX_LEN characters */
		obj->line[i++] = '\0';
	    obj->in_buf++;
	}
    }
    if (i <= MAX_LEN)
	obj->line[i] = '\0';
    if (!obj->end_reached)
	obj->in_buf++;		/* move pass '\n' */

    return obj->line;
}

static bool
match_string(MY_OBJ * obj, char *string)
{
    char *match = get_line(obj);
    return strstr(match, string) != 0;
}

/*
 * Go back 'n' lines in text file. Called by dialog_textbox().
 * 'in_buf' will be updated to point to the desired line in 'buf'.
 */
static void
back_lines(MY_OBJ * obj, int n)
{
    long fpos;
    int i, val_to_tabize;

    obj->begin_reached = FALSE;
    /* We have to distinguish between end_reached and !end_reached since at end
       * of file, the line is not ended by a '\n'.  The code inside 'if'
       * basically does a '--in_buf' to move one character backward so as to
       * skip '\n' of the previous line */
    if (!obj->end_reached) {
	/* Either beginning of buffer or beginning of file reached? */

	if (obj->in_buf == 0) {
	    fpos = ftell_obj(obj);

	    if (fpos > obj->fd_bytes_read) {	/* Not beginning of file yet */
		/* We've reached beginning of buffer, but not beginning of file
		 * yet, so read previous part of file into buffer.  Note that
		 * we only move backward for BUF_SIZE/2 bytes, but not BUF_SIZE
		 * bytes to avoid re-reading again in print_page() later
		 */
		/* Really possible to move backward BUF_SIZE/2 bytes? */
		if (fpos < BUF_SIZE / 2 + obj->fd_bytes_read) {
		    /* No, move less then */
		    lseek_obj(obj, 0, SEEK_SET);
		    val_to_tabize = fpos - obj->fd_bytes_read;
		} else {	/* Move backward BUF_SIZE/2 bytes */
		    lseek_obj(obj, -(BUF_SIZE / 2 + obj->fd_bytes_read), SEEK_CUR);
		    val_to_tabize = BUF_SIZE / 2;
		}
		read_high(obj, BUF_SIZE);

		obj->in_buf = tabize(obj, val_to_tabize, 0);

	    } else {		/* Beginning of file reached */
		obj->begin_reached = TRUE;
		return;
	    }
	}
	obj->in_buf--;
	if (obj->buf[obj->in_buf] != '\n')
	    /* Something's wrong... */
	    dlg_exiterr("Internal error in back_lines().");
    }

    /* Go back 'n' lines */
    for (i = 0; i < n; i++) {
	do {
	    if (obj->in_buf == 0) {
		fpos = ftell_obj(obj);

		if (fpos > obj->fd_bytes_read) {
		    /* Really possible to move backward BUF_SIZE/2 bytes? */
		    if (fpos < BUF_SIZE / 2 + obj->fd_bytes_read) {
			/* No, move less then */
			lseek_obj(obj, 0, SEEK_SET);
			val_to_tabize = fpos - obj->fd_bytes_read;
		    } else {	/* Move backward BUF_SIZE/2 bytes */
			lseek_obj(obj, -(BUF_SIZE / 2 + obj->fd_bytes_read), SEEK_CUR);
			val_to_tabize = BUF_SIZE / 2;
		    }
		    read_high(obj, BUF_SIZE);

		    obj->in_buf = tabize(obj, val_to_tabize, 0);

		} else {	/* Beginning of file reached */
		    obj->begin_reached = TRUE;
		    return;
		}
	    }
	} while (obj->buf[--(obj->in_buf)] != '\n');
    }
    obj->in_buf++;
}

/*
 * Print a new line of text.
 */
static void
print_line(MY_OBJ * obj, int row, int width)
{
    int i, y, x;
    char *line;
    line = get_line(obj);
    line += MIN((int) strlen(line), obj->hscroll);	/* Scroll horizontally */
    (void) wmove(obj->text, row, 0);	/* move cursor to correct line */
    (void) waddch(obj->text, ' ');
#ifdef NCURSES_VERSION
    (void) waddnstr(obj->text, line, MIN((int) strlen(line), width - 2));
#else
    line[MIN((int) strlen(line), width - 2)] = '\0';
    waddstr(obj->text, line);
#endif

    getyx(obj->text, y, x);
    /* Clear 'residue' of previous line */
    for (i = 0; i < width - x; i++)
	(void) waddch(obj->text, ' ');
}

/*
 * Print a new page of text.
 */
static void
print_page(MY_OBJ * obj, int height, int width)
{
    int i, passed_end = 0;

    obj->page_length = 0;
    for (i = 0; i < height; i++) {
	print_line(obj, i, width);
	if (!passed_end)
	    obj->page_length++;
	if (obj->end_reached && !passed_end)
	    passed_end = 1;
    }
    (void) wnoutrefresh(obj->text);
}

/*
 * Print current position
 */
static void
print_position(MY_OBJ * obj, WINDOW *win, int height, int width)
{
    long fpos;
    int percent;

    fpos = ftell_obj(obj);

    wattrset(win, position_indicator_attr);
    percent = !obj->file_size
	? 100
	: ((fpos
	    - obj->fd_bytes_read
	    + tabize(obj, obj->in_buf, 1)) * 100)
	/ obj->file_size;
    (void) wmove(win, height - 3, width - 9);
    (void) wprintw(win, "(%3d%%)", percent);

    dlg_draw_arrows(win, TRUE, TRUE, 5, 0, height - 3);
}

/*
 * Display a dialog box and get the search term from user
 */
static int
get_search_term(WINDOW *dialog, char *input, int height, int width)
{