/* vi: set sw=4 ts=4: */ /* * Mini more implementation for busybox * * Copyright (C) 1995, 1996 by Bruce Perens . * Copyright (C) 1999-2004 by Erik Andersen * * Latest version blended together by Erik Andersen , * based on the original more implementation by Bruce, and code from the * Debian boot-floppies team. * * Termios corrects by Vladimir Oleynik * * Licensed under GPLv2 or later, see file License in this tarball for details. */ #include "busybox.h" #if ENABLE_FEATURE_USE_TERMIOS static int cin_fileno; #include #define setTermSettings(fd, argp) tcsetattr(fd, TCSANOW, argp) #define getTermSettings(fd, argp) tcgetattr(fd, argp); static struct termios initial_settings, new_settings; static void set_tty_to_initial_mode(void) { setTermSettings(cin_fileno, &initial_settings); } static void gotsig(int sig) { putchar('\n'); exit(EXIT_FAILURE); } #endif /* FEATURE_USE_TERMIOS */ int more_main(int argc, char **argv); int more_main(int argc, char **argv) { int c, lines, input = 0; int please_display_more_prompt = 0; struct stat st; FILE *file; FILE *cin; int len, page_height; int terminal_width; int terminal_height; argv++; /* Another popular pager, most, detects when stdout * is not a tty and turns into cat. This makes sense. */ if (!isatty(STDOUT_FILENO)) return bb_cat(argv); cin = fopen(CURRENT_TTY, "r"); if (!cin) return bb_cat(argv); #if ENABLE_FEATURE_USE_TERMIOS cin_fileno = fileno(cin); getTermSettings(cin_fileno, &initial_settings); new_settings = initial_settings; new_settings.c_lflag &= ~ICANON; new_settings.c_lflag &= ~ECHO; new_settings.c_cc[VMIN] = 1; new_settings.c_cc[VTIME] = 0; setTermSettings(cin_fileno, &new_settings); atexit(set_tty_to_initial_mode); signal(SIGINT, gotsig); signal(SIGQUIT, gotsig); signal(SIGTERM, gotsig); #endif please_display_more_prompt = 2; do { file = stdin; if (*argv) { file = fopen_or_warn(*argv, "r"); if (!file) continue; } st.st_size = 0; fstat(fileno(file), &st); please_display_more_prompt &= ~1; /* never returns w, h <= 1 */ get_terminal_width_height(fileno(cin), &terminal_width, &terminal_height); terminal_width -= 1; terminal_height -= 1; len = 0; lines = 0; page_height = terminal_height; while ((c = getc(file)) != EOF) { if ((please_display_more_prompt & 3) == 3) { len = printf("--More-- "); if (/*file != stdin &&*/ st.st_size > 0) { len += printf("(%d%% of %"OFF_FMT"d bytes)", (int) (ftello(file)*100 / st.st_size), st.st_size); } fflush(stdout); /* * We've just displayed the "--More--" prompt, so now we need * to get input from the user. */ input = getc(cin); #if !ENABLE_FEATURE_USE_TERMIOS printf("\033[A"); /* up cursor */ #endif /* Erase the "More" message */ printf("\r%*s\r", len, ""); len = 0; lines = 0; /* Bottom line on page will become top line * after one page forward. Thus -1: */ page_height = terminal_height - 1; please_display_more_prompt &= ~1; if (input == 'q') goto end; } /* * There are two input streams to worry about here: * * c : the character we are reading from the file being "mored" * input : a character received from the keyboard * * If we hit a newline in the _file_ stream, we want to test and * see if any characters have been hit in the _input_ stream. This * allows the user to quit while in the middle of a file. */ if (c == '\n') { /* increment by just one line if we are at * the end of this line */ if (input == '\n') please_display_more_prompt |= 1; /* Adjust the terminal height for any overlap, so that * no lines get lost off the top. */ if (len >= terminal_width) { int quot, rem; quot = len / terminal_width; rem = len - (quot * terminal_width); page_height -= (quot - 1); if (rem) page_height--; } if (++lines >= page_height) { please_display_more_prompt |= 1; } len = 0; } /* * If we just read a newline from the file being 'mored' and any * key other than a return is hit, scroll by one page */ putc(c, stdout); /* My small mind cannot fathom tabs, backspaces, * and UTF-8 */ len++; } fclose(file); fflush(stdout); } while (*argv && *++argv); end: return 0; }