patch-1.3.60 linux/scripts/lxdialog/textbox.c

• Lines: 538
• Date: Wed Feb 7 09:47:28 1996
• Orig file: v1.3.59/linux/scripts/lxdialog/textbox.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.59/linux/scripts/lxdialog/textbox.c linux/scripts/lxdialog/textbox.c
@@ -0,0 +1,537 @@
+/*
+ *  textbox.c -- implements the text box
+ *
+ *  ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk)
+ *  MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcap@cfw.com)
+ *
+ *  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"
+
+static void back_lines (int n);
+static void print_page (WINDOW * win, int height, int width);
+static void print_line (WINDOW * win, int row, int width);
+static char *get_line (void);
+static void print_position (WINDOW * win, int height, int width);
+
+static int hscroll = 0, fd, file_size, bytes_read;
+static int begin_reached = 1, end_reached = 0, page_length;
+static char *buf, *page;
+
+/*
+ * Display text from a file in a dialog box.
+ */
+int
+dialog_textbox (const char *title, const char *file, int height, int width)
+{
+    int i, x, y, cur_x, cur_y, fpos, key = 0;
+    int passed_end;
+    char search_term[MAX_LEN + 1];
+    WINDOW *dialog, *text;
+
+    search_term[0] = '\0';	/* no search term entered yet */
+
+    /* Open input file for reading */
+    if ((fd = open (file, O_RDONLY)) == -1) {
+	endwin ();
+	fprintf (stderr,
+		 "\nCan't open input file in dialog_textbox().\n");
+	exit (-1);
+    }
+    /* Get file size. Actually, 'file_size' is the real file size - 1,
+       since it's only the last byte offset from the beginning */
+    if ((file_size = lseek (fd, 0, SEEK_END)) == -1) {
+	endwin ();
+	fprintf (stderr, "\nError getting file size in dialog_textbox().\n");
+	exit (-1);
+    }
+    /* Restore file pointer to beginning of file after getting file size */
+    if (lseek (fd, 0, SEEK_SET) == -1) {
+	endwin ();
+	fprintf (stderr, "\nError moving file pointer in dialog_textbox().\n");
+	exit (-1);
+    }
+    /* Allocate space for read buffer */
+    if ((buf = malloc (BUF_SIZE + 1)) == NULL) {
+	endwin ();
+	fprintf (stderr, "\nCan't allocate memory in dialog_textbox().\n");
+	exit (-1);
+    }
+    if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
+	endwin ();
+	fprintf (stderr, "\nError reading file in dialog_textbox().\n");
+	exit (-1);
+    }
+    buf[bytes_read] = '\0';	/* mark end of valid data */
+    page = buf;			/* page is pointer to start of page to be displayed */
+
+    /* center dialog box on screen */
+    x = (COLS - width) / 2;
+    y = (LINES - height) / 2;
+
+
+    draw_shadow (stdscr, y, x, height, width);
+
+    dialog = newwin (height, width, y, x);
+    keypad (dialog, TRUE);
+
+    /* Create window for text region, used for scrolling text */
+    text = subwin (dialog, height - 4, width - 2, y + 1, x + 1);
+
+    keypad (text, TRUE);
+
+    /* register the new window, along with its borders */
+    draw_box (dialog, 0, 0, height, width, dialog_attr, border_attr);
+
+    wattrset (dialog, border_attr);
+    mvwaddch (dialog, height-3, 0, ACS_LTEE);
+    for (i = 0; i < width - 2; i++)
+	waddch (dialog, ACS_HLINE);
+    wattrset (dialog, dialog_attr);
+    waddch (dialog, ACS_RTEE);
+
+    if (title != NULL) {
+	wattrset (dialog, title_attr);
+	mvwaddch (dialog, 0, (width - strlen(title))/2 - 1, ' ');
+	waddstr (dialog, (char *)title);
+	waddch (dialog, ' ');
+    }
+    print_button (dialog, " Exit ", height - 2, width / 2 - 4, TRUE);
+    wnoutrefresh (dialog);
+    getyx (dialog, cur_y, cur_x);	/* Save cursor position */
+
+    /* Print first page of text */
+    attr_clear (text, height - 4, width - 2, dialog_attr);
+    print_page (text, height - 4, width - 2);
+    print_position (dialog, height, width);
+    wmove (dialog, cur_y, cur_x);	/* Restore cursor position */
+    wrefresh (dialog);
+
+    while ((key != ESC) && (key != '\n')) {
+	key = wgetch (dialog);
+	switch (key) {
+	case 'E':		/* Exit */
+	case 'e':
+	case 'X':
+	case 'x':
+	    delwin (dialog);
+	    free (buf);
+	    close (fd);
+	    return 0;
+	case 'g':		/* First page */
+	case KEY_HOME:
+	    if (!begin_reached) {
+		begin_reached = 1;
+		/* First page not in buffer? */
+		if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
+		    endwin ();
+		    fprintf (stderr,
+		      "\nError moving file pointer in dialog_textbox().\n");
+		    exit (-1);
+		}
+		if (fpos > bytes_read) {	/* Yes, we have to read it in */
+		    if (lseek (fd, 0, SEEK_SET) == -1) {
+			endwin ();
+			fprintf (stderr, "\nError moving file pointer in "
+				 "dialog_textbox().\n");
+			exit (-1);
+		    }
+		    if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
+			endwin ();
+			fprintf (stderr,
+			     "\nError reading file in dialog_textbox().\n");
+			exit (-1);
+		    }
+		    buf[bytes_read] = '\0';
+		}
+		page = buf;
+		print_page (text, height - 4, width - 2);
+		print_position (dialog, height, width);
+		wmove (dialog, cur_y, cur_x);	/* Restore cursor position */
+		wrefresh (dialog);
+	    }
+	    break;
+	case 'G':		/* Last page */
+	case KEY_END:
+
+	    end_reached = 1;
+	    /* Last page not in buffer? */
+	    if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
+		endwin ();
+		fprintf (stderr,
+		      "\nError moving file pointer in dialog_textbox().\n");
+		exit (-1);
+	    }
+	    if (fpos < file_size) {	/* Yes, we have to read it in */
+		if (lseek (fd, -BUF_SIZE, SEEK_END) == -1) {
+		    endwin ();
+		    fprintf (stderr,
+		      "\nError moving file pointer in dialog_textbox().\n");
+		    exit (-1);
+		}
+		if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
+		    endwin ();
+		    fprintf (stderr,
+			     "\nError reading file in dialog_textbox().\n");
+		    exit (-1);
+		}
+		buf[bytes_read] = '\0';
+	    }
+	    page = buf + bytes_read;
+	    back_lines (height - 4);
+	    print_page (text, height - 4, width - 2);
+	    print_position (dialog, height, width);
+	    wmove (dialog, cur_y, cur_x);	/* Restore cursor position */
+	    wrefresh (dialog);
+	    break;
+	case 'K':		/* Previous line */
+	case 'k':
+	case KEY_UP:
+	    if (!begin_reached) {
+		back_lines (page_length + 1);
+
+		/* We don't call print_page() here but use scrolling to ensure
+		   faster screen update. However, 'end_reached' and
+		   'page_length' should still be updated, and 'page' should
+		   point to start of next page. This is done by calling
+		   get_line() in the following 'for' loop. */
+		scrollok (text, TRUE);
+		wscrl (text, -1);	/* Scroll text region down one line */
+		scrollok (text, FALSE);
+		page_length = 0;
+		passed_end = 0;
+		for (i = 0; i < height - 4; i++) {
+		    if (!i) {
+			/* print first line of page */
+			print_line (text, 0, width - 2);
+			wnoutrefresh (text);
+		    } else
+			/* Called to update 'end_reached' and 'page' */
+			get_line ();
+		    if (!passed_end)
+			page_length++;
+		    if (end_reached && !passed_end)
+			passed_end = 1;
+		}
+
+		print_position (dialog, height, width);
+		wmove (dialog, cur_y, cur_x);	/* Restore cursor position */
+		wrefresh (dialog);
+	    }
+	    break;
+	case 'B':		/* Previous page */
+	case 'b':
+	case KEY_PPAGE:
+	    if (begin_reached)
+		break;
+	    back_lines (page_length + height - 4);
+	    print_page (text, height - 4, width - 2);
+	    print_position (dialog, height, width);
+	    wmove (dialog, cur_y, cur_x);
+	    wrefresh (dialog);
+	    break;
+	case 'J':		/* Next line */
+	case 'j':
+	case KEY_DOWN:
+	    if (!end_reached) {
+		begin_reached = 0;
+		scrollok (text, TRUE);
+		scroll (text);	/* Scroll text region up one line */
+		scrollok (text, FALSE);
+		print_line (text, height - 5, width - 2);
+		wnoutrefresh (text);
+		print_position (dialog, height, width);
+		wmove (dialog, cur_y, cur_x);	/* Restore cursor position */
+		wrefresh (dialog);
+	    }
+	    break;
+	case KEY_NPAGE:		/* Next page */
+	case ' ':
+	    if (end_reached)
+		break;
+
+	    begin_reached = 0;
+	    print_page (text, height - 4, width - 2);
+	    print_position (dialog, height, width);
+	    wmove (dialog, cur_y, cur_x);
+	    wrefresh (dialog);
+	    break;
+	case '0':		/* Beginning of line */
+	case 'H':		/* Scroll left */
+	case 'h':
+	case KEY_LEFT:
+	    if (hscroll <= 0)
+		break;
+
+	    if (key == '0')
+		hscroll = 0;
+	    else
+		hscroll--;
+	    /* Reprint current page to scroll horizontally */
+	    back_lines (page_length);
+	    print_page (text, height - 4, width - 2);
+	    wmove (dialog, cur_y, cur_x);
+	    wrefresh (dialog);
+	    break;
+	case 'L':		/* Scroll right */
+	case 'l':
+	case KEY_RIGHT:
+	    if (hscroll >= MAX_LEN)
+		break;
+	    hscroll++;
+	    /* Reprint current page to scroll horizontally */
+	    back_lines (page_length);
+	    print_page (text, height - 4, width - 2);
+	    wmove (dialog, cur_y, cur_x);
+	    wrefresh (dialog);
+	    break;
+	case ESC:
+	    break;
+	}
+    }
+
+    delwin (dialog);
+    free (buf);
+    close (fd);
+    return -1;			/* ESC pressed */
+}
+
+/*
+ * Go back 'n' lines in text file. Called by dialog_textbox().
+ * 'page' will be updated to point to the desired line in 'buf'.
+ */
+static void
+back_lines (int n)
+{
+    int i, fpos;
+
+    begin_reached = 0;
+    /* 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 '--page' to move one
+       character backward so as to skip '\n' of the previous line */
+    if (!end_reached) {
+	/* Either beginning of buffer or beginning of file reached? */
+	if (page == buf) {
+	    if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
+		endwin ();
+		fprintf (stderr, "\nError moving file pointer in "
+			 "back_lines().\n");
+		exit (-1);
+	    }
+	    if (fpos > 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 + bytes_read) {
+		    /* No, move less then */
+		    if (lseek (fd, 0, SEEK_SET) == -1) {
+			endwin ();
+			fprintf (stderr, "\nError moving file pointer in "
+				 "back_lines().\n");
+			exit (-1);
+		    }
+		    page = buf + fpos - bytes_read;
+		} else {	/* Move backward BUF_SIZE/2 bytes */
+		    if (lseek (fd, -(BUF_SIZE / 2 + bytes_read), SEEK_CUR)
+			== -1) {
+			endwin ();
+			fprintf (stderr, "\nError moving file pointer "
+				 "in back_lines().\n");
+			exit (-1);
+		    }
+		    page = buf + BUF_SIZE / 2;
+		}
+		if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
+		    endwin ();
+		    fprintf (stderr, "\nError reading file in back_lines().\n");
+		    exit (-1);
+		}
+		buf[bytes_read] = '\0';
+	    } else {		/* Beginning of file reached */
+		begin_reached = 1;
+		return;
+	    }
+	}
+	if (*(--page) != '\n') {	/* '--page' here */
+	    /* Something's wrong... */
+	    endwin ();
+	    fprintf (stderr, "\nInternal error in back_lines().\n");
+	    exit (-1);
+	}
+    }
+    /* Go back 'n' lines */
+    for (i = 0; i < n; i++)
+	do {
+	    if (page == buf) {
+		if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
+		    endwin ();
+		    fprintf (stderr,
+			  "\nError moving file pointer in back_lines().\n");
+		    exit (-1);
+		}
+		if (fpos > bytes_read) {
+		    /* Really possible to move backward BUF_SIZE/2 bytes? */
+		    if (fpos < BUF_SIZE / 2 + bytes_read) {
+			/* No, move less then */
+			if (lseek (fd, 0, SEEK_SET) == -1) {
+			    endwin ();
+			    fprintf (stderr, "\nError moving file pointer "
+				     "in back_lines().\n");
+			    exit (-1);
+			}
+			page = buf + fpos - bytes_read;
+		    } else {	/* Move backward BUF_SIZE/2 bytes */
+			if (lseek (fd, -(BUF_SIZE / 2 + bytes_read),
+				   SEEK_CUR) == -1) {
+			    endwin ();
+			    fprintf (stderr, "\nError moving file pointer"
+				     " in back_lines().\n");
+			    exit (-1);
+			}
+			page = buf + BUF_SIZE / 2;
+		    }
+		    if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
+			endwin ();
+			fprintf (stderr, "\nError reading file in "
+				 "back_lines().\n");
+			exit (-1);
+		    }
+		    buf[bytes_read] = '\0';
+		} else {	/* Beginning of file reached */
+		    begin_reached = 1;
+		    return;
+		}
+	    }
+	} while (*(--page) != '\n');
+    page++;
+}
+
+/*
+ * Print a new page of text. Called by dialog_textbox().
+ */
+static void
+print_page (WINDOW * win, int height, int width)
+{
+    int i, passed_end = 0;
+
+    page_length = 0;
+    for (i = 0; i < height; i++) {
+	print_line (win, i, width);
+	if (!passed_end)
+	    page_length++;
+	if (end_reached && !passed_end)
+	    passed_end = 1;
+    }
+    wnoutrefresh (win);
+}
+
+/*
+ * Print a new line of text. Called by dialog_textbox() and print_page().
+ */
+static void
+print_line (WINDOW * win, int row, int width)
+{
+    int i, y, x;
+    char *line;
+
+    line = get_line ();
+    line += MIN (strlen (line), hscroll);	/* Scroll horizontally */
+    wmove (win, row, 0);	/* move cursor to correct line */
+    waddch (win, ' ');
+    waddnstr (win, line, MIN (strlen (line), width - 2));
+
+    getyx (win, y, x);
+    /* Clear 'residue' of previous line */
+    for (i = 0; i < width - x; i++)
+	waddch (win, ' ');
+}
+
+/*
+ * Return current line of text. Called by dialog_textbox() and print_line().
+ * '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 (void)
+{
+    int i = 0, fpos;
+    static char line[MAX_LEN + 1];
+
+    end_reached = 0;
+    while (*page != '\n') {
+	if (*page == '\0') {
+	    /* Either end of file or end of buffer reached */
+	    if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
+		endwin ();
+		fprintf (stderr, "\nError moving file pointer in "
+			 "get_line().\n");
+		exit (-1);
+	    }
+	    if (fpos < 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 */
+		if ((bytes_read = read (fd, buf, BUF_SIZE)) == -1) {
+		    endwin ();
+		    fprintf (stderr, "\nError reading file in get_line().\n");
+		    exit (-1);
+		}
+		buf[bytes_read] = '\0';
+		page = buf;
+	    } else {
+		if (!end_reached)
+		    end_reached = 1;
+		break;
+	    }
+	} else if (i < MAX_LEN)
+	    line[i++] = *(page++);
+	else {
+	    /* Truncate lines longer than MAX_LEN characters */
+	    if (i == MAX_LEN)
+		line[i++] = '\0';
+	    page++;
+	}
+    }
+    if (i <= MAX_LEN)
+	line[i] = '\0';
+    if (!end_reached)
+	page++;			/* move pass '\n' */
+
+    return line;
+}
+
+/*
+ * Print current position
+ */
+static void
+print_position (WINDOW * win, int height, int width)
+{
+    int fpos, percent;
+
+    if ((fpos = lseek (fd, 0, SEEK_CUR)) == -1) {
+	endwin ();
+	fprintf (stderr, "\nError moving file pointer in print_position().\n");
+	exit (-1);
+    }
+    wattrset (win, position_indicator_attr);
+    percent = !file_size ?
+	100 : ((fpos - bytes_read + page - buf) * 100) / file_size;
+    wmove (win, height - 3, width - 9);
+    wprintw (win, "(%3d%%)", percent);
+}