*
* Termios corrects by Vladimir Oleynik <dzo@simtreas.ru>
*
- * Licensed under GPLv2 or later, see file License in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
+//config:config MORE
+//config: bool "more (6.7 kb)"
+//config: default y
+//config: help
+//config: more is a simple utility which allows you to read text one screen
+//config: sized page at a time. If you want to read text that is larger than
+//config: the screen, and you are using anything faster than a 300 baud modem,
+//config: you will probably find this utility very helpful. If you don't have
+//config: any need to reading text files, you can leave this disabled.
+
+//applet:IF_MORE(APPLET(more, BB_DIR_BIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_MORE) += more.o
+
+//usage:#define more_trivial_usage
+//usage: "[FILE]..."
+//usage:#define more_full_usage "\n\n"
+//usage: "View FILE (or stdin) one screenful at a time"
+//usage:
+//usage:#define more_example_usage
+//usage: "$ dmesg | more\n"
#include "libbb.h"
-#if ENABLE_FEATURE_USE_TERMIOS
-#include <termios.h>
-#endif /* FEATURE_USE_TERMIOS */
-
-
-#if ENABLE_FEATURE_USE_TERMIOS
+#include "common_bufsiz.h"
struct globals {
- int cin_fileno;
+ int tty_fileno;
+ unsigned terminal_width;
+ unsigned terminal_height;
struct termios initial_settings;
- struct termios new_settings;
-};
+} FIX_ALIASING;
#define G (*(struct globals*)bb_common_bufsiz1)
-//#define G (*ptr_to_globals)
-#define INIT_G() ((void)0)
-//#define INIT_G() PTR_TO_GLOBALS = xzalloc(sizeof(G))
-#define initial_settings (G.initial_settings)
-#define new_settings (G.new_settings )
-#define cin_fileno (G.cin_fileno )
+#define INIT_G() do { setup_common_bufsiz(); } while (0)
-#define setTermSettings(fd, argp) tcsetattr(fd, TCSANOW, argp)
-#define getTermSettings(fd, argp) tcgetattr(fd, argp)
+static void get_wh(void)
+{
+ /* never returns w, h <= 1 */
+ get_terminal_width_height(G.tty_fileno, &G.terminal_width, &G.terminal_height);
+ G.terminal_height -= 1;
+}
-static void gotsig(int sig)
+static void tcsetattr_tty_TCSANOW(struct termios *settings)
{
- bb_putchar('\n');
- setTermSettings(cin_fileno, &initial_settings);
- exit(EXIT_FAILURE);
+ tcsetattr(G.tty_fileno, TCSANOW, settings);
}
-#else /* !FEATURE_USE_TERMIOS */
-#define INIT_G() ((void)0)
-#define setTermSettings(fd, argp) ((void)0)
-#endif /* FEATURE_USE_TERMIOS */
+static void gotsig(int sig UNUSED_PARAM)
+{
+ /* bb_putchar_stderr doesn't use stdio buffering,
+ * therefore it is safe in signal handler */
+ bb_putchar_stderr('\n');
+ tcsetattr_tty_TCSANOW(&G.initial_settings);
+ _exit(EXIT_FAILURE);
+}
#define CONVERTED_TAB_SIZE 8
int more_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int more_main(int argc, char **argv)
+int more_main(int argc UNUSED_PARAM, char **argv)
{
- int c = c; /* for gcc */
- int lines;
+ int c = c; /* for compiler */
int input = 0;
int spaces = 0;
int please_display_more_prompt;
- struct stat st;
- FILE *file;
- FILE *cin;
- int len;
- int terminal_width;
- int terminal_height;
+ FILE *tty;
INIT_G();
- argv++;
+ /* Parse options */
+ /* Accepted but ignored: */
+ /* -d Display help instead of ringing bell */
+ /* -f Count logical lines (IOW: long lines are not folded) */
+ /* -l Do not pause after any line containing a ^L (form feed) */
+ /* -s Squeeze blank lines into one */
+ /* -u Suppress underlining */
+ getopt32(argv, "dflsu");
+ argv += optind;
+
/* 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)
+ tty = fopen_for_read(CURRENT_TTY);
+ if (!tty)
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);
- signal(SIGINT, gotsig);
- signal(SIGQUIT, gotsig);
- signal(SIGTERM, gotsig);
-#endif
+ G.tty_fileno = fileno(tty);
+
+ /* Turn on unbuffered input; turn off echoing */
+ set_termios_to_raw(G.tty_fileno, &G.initial_settings, 0);
+ bb_signals(BB_FATAL_SIGS, gotsig);
do {
+ struct stat st;
+ FILE *file;
+ int len;
+ int lines;
+
file = stdin;
if (*argv) {
file = fopen_or_warn(*argv, "r");
st.st_size = 0;
fstat(fileno(file), &st);
- please_display_more_prompt = 0;
- /* never returns w, h <= 1 */
- get_terminal_width_height(fileno(cin), &terminal_width, &terminal_height);
- terminal_height -= 1;
+ get_wh();
+ please_display_more_prompt = 0;
len = 0;
lines = 0;
- while (spaces || (c = getc(file)) != EOF) {
+ for (;;) {
int wrap;
+
if (spaces)
spaces--;
+ else {
+ c = getc(file);
+ if (c == EOF) break;
+ }
loop_top:
if (input != 'r' && please_display_more_prompt) {
len = printf("--More-- ");
- if (st.st_size > 0) {
- len += printf("(%d%% of %"OFF_FMT"d bytes)",
- (int) (ftello(file)*100 / st.st_size),
+ if (st.st_size != 0) {
+ uoff_t d = (uoff_t)st.st_size / 100;
+ if (d == 0)
+ d = 1;
+ len += printf("(%u%% of %"OFF_FMT"u bytes)",
+ (int) ((uoff_t)ftello(file) / d),
st.st_size);
}
- fflush(stdout);
/*
* We've just displayed the "--More--" prompt, so now we need
* to get input from the user.
*/
for (;;) {
- input = getc(cin);
+ fflush_all();
+ input = getc(tty);
input = tolower(input);
-#if !ENABLE_FEATURE_USE_TERMIOS
- printf("\033[A"); /* up cursor */
-#endif
/* Erase the last message */
printf("\r%*s\r", len, "");
+ if (input == 'q')
+ goto end;
/* Due to various multibyte escape
* sequences, it's not ok to accept
* any input as a command to scroll
* the screen. We only allow known
* commands, else we show help msg. */
- if (input == ' ' || input == '\n' || input == 'q' || input == 'r')
+ if (input == ' ' || input == '\n' || input == 'r')
break;
len = printf("(Enter:next line Space:next page Q:quit R:show the rest)");
}
lines = 0;
please_display_more_prompt = 0;
- if (input == 'q')
- goto end;
-
/* The user may have resized the terminal.
* Re-read the dimensions. */
-#if ENABLE_FEATURE_USE_TERMIOS
- get_terminal_width_height(cin_fileno, &terminal_width, &terminal_height);
- terminal_height -= 1;
-#endif
+ get_wh();
}
/* Crudely convert tabs into spaces, which are
* a bajillion times easier to deal with. */
if (c == '\t') {
- spaces = CONVERTED_TAB_SIZE - 1;
+ spaces = ((unsigned)~len) % CONVERTED_TAB_SIZE;
c = ' ';
- }
+ }
/*
* There are two input streams to worry about here:
* see if any characters have been hit in the _input_ stream. This
* allows the user to quit while in the middle of a file.
*/
- wrap = (++len > terminal_width);
+ wrap = (++len > G.terminal_width);
if (c == '\n' || wrap) {
/* Then outputting this character
* will move us to a new line. */
- if (++lines >= terminal_height || input == '\n')
+ if (++lines >= G.terminal_height || input == '\n')
please_display_more_prompt = 1;
len = 0;
}
}
/* My small mind cannot fathom backspaces and UTF-8 */
putchar(c);
+ die_if_ferror_stdout(); /* if tty was destroyed (closed xterm, etc) */
}
fclose(file);
- fflush(stdout);
+ fflush_all();
} while (*argv && *++argv);
end:
- setTermSettings(cin_fileno, &initial_settings);
+ tcsetattr_tty_TCSANOW(&G.initial_settings);
return 0;
}