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author | Denys Vlasenko | 2017-01-11 10:38:52 +0100 |
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committer | Denys Vlasenko | 2017-01-11 10:38:52 +0100 |
commit | c5891fe1af821dae83a8b1df088462b6989d089b (patch) | |
tree | ef426c50dfd05a3e8623408c3208a442e28e9dd7 /util-linux/more.c | |
parent | 80f806cac9b418c07b149a683a4d1d989507d4d8 (diff) | |
download | busybox-c5891fe1af821dae83a8b1df088462b6989d089b.zip busybox-c5891fe1af821dae83a8b1df088462b6989d089b.tar.gz |
more: hardcode FEATURE_USE_TERMIOS=y in this applet; code shrink
function old new delta
get_wh - 27 +27
tcsetattr_tty_TCSANOW - 18 +18
gotsig 35 27 -8
more_main 835 759 -76
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 0/2 up/down: 45/-84) Total: -39 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'util-linux/more.c')
-rw-r--r-- | util-linux/more.c | 106 |
1 files changed, 49 insertions, 57 deletions
diff --git a/util-linux/more.c b/util-linux/more.c index 934b30f..7fa60bd 100644 --- a/util-linux/more.c +++ b/util-linux/more.c @@ -38,32 +38,34 @@ #include "libbb.h" #include "common_bufsiz.h" -/* Support for FEATURE_USE_TERMIOS */ - 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 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) \ -do { \ - if (ENABLE_FEATURE_USE_TERMIOS) \ - tcsetattr(fd, TCSANOW, argp); \ -} while (0) -#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 tcsetattr_tty_TCSANOW(struct termios *settings) +{ + tcsetattr(G.tty_fileno, TCSANOW, settings); +} 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'); - setTermSettings(cin_fileno, &initial_settings); + tcsetattr_tty_TCSANOW(&G.initial_settings); _exit(EXIT_FAILURE); } @@ -73,22 +75,16 @@ int more_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int more_main(int argc UNUSED_PARAM, char **argv) { int c = c; /* for compiler */ - int lines; int input = 0; int spaces = 0; int please_display_more_prompt; - struct stat st; - FILE *file; - FILE *cin; - int len; - unsigned terminal_width; - unsigned terminal_height; + FILE *tty; INIT_G(); /* Parse options */ /* Accepted but ignored: */ - /* -d Display help instead of ringing bell is pressed */ + /* -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 */ @@ -100,26 +96,25 @@ int more_main(int argc UNUSED_PARAM, char **argv) * is not a tty and turns into cat. This makes sense. */ if (!isatty(STDOUT_FILENO)) return bb_cat(argv); - cin = fopen_for_read(CURRENT_TTY); - 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 | ECHO); - new_settings.c_cc[VMIN] = 1; - new_settings.c_cc[VTIME] = 0; - setTermSettings(cin_fileno, &new_settings); - bb_signals(0 - + (1 << SIGINT) - + (1 << SIGQUIT) - + (1 << SIGTERM) - , gotsig); - } + G.tty_fileno = fileno(tty); + tcgetattr(G.tty_fileno, &G.initial_settings); + G.new_settings = G.initial_settings; + G.new_settings.c_lflag &= ~(ICANON | ECHO); + G.new_settings.c_cc[VMIN] = 1; + G.new_settings.c_cc[VTIME] = 0; + tcsetattr_tty_TCSANOW(&G.new_settings); + 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"); @@ -129,17 +124,20 @@ int more_main(int argc UNUSED_PARAM, char **argv) 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-- "); @@ -151,26 +149,26 @@ int more_main(int argc UNUSED_PARAM, char **argv) (int) ((uoff_t)ftello(file) / d), st.st_size); } - fflush_all(); /* * 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"); /* cursor up */ /* 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)"); } @@ -178,15 +176,9 @@ int more_main(int argc UNUSED_PARAM, char **argv) 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; - } + get_wh(); } /* Crudely convert tabs into spaces, which are @@ -206,11 +198,11 @@ int more_main(int argc UNUSED_PARAM, char **argv) * 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; } @@ -230,6 +222,6 @@ int more_main(int argc UNUSED_PARAM, char **argv) fflush_all(); } while (*argv && *++argv); end: - setTermSettings(cin_fileno, &initial_settings); + tcsetattr_tty_TCSANOW(&G.initial_settings); return 0; } |