| -rw-r--r-- | scripts/lxdialog/textbox.c | 556 |
1 files changed, 556 insertions, 0 deletions
diff --git a/scripts/lxdialog/textbox.c b/scripts/lxdialog/textbox.c new file mode 100644 index 0000000..ecf5541 --- a/dev/null +++ b/scripts/lxdialog/textbox.c @@ -0,0 +1,556 @@ +/* + * 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); + wattrset (text, dialog_attr); + wbkgdset (text, dialog_attr & A_COLOR); + + 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); + wbkgdset (dialog, dialog_attr & A_COLOR); + waddch (dialog, ACS_RTEE); + + if (title != NULL && strlen(title) >= width-2 ) { + /* truncate long title -- mec */ + char * title2 = malloc(width-2+1); + memcpy( title2, title, width-2 ); + title2[width-2] = '\0'; + title = title2; + } + + 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 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 */ +#if OLD_NCURSES + { + int i; + for (i = 0; i < width - x; i++) + waddch (win, ' '); + } +#else + wclrtoeol(win); +#endif +} + +/* + * 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); + wbkgdset (win, position_indicator_attr & A_COLOR); + percent = !file_size ? + 100 : ((fpos - bytes_read + page - buf) * 100) / file_size; + wmove (win, height - 3, width - 9); + wprintw (win, "(%3d%%)", percent); +} |