*: use _exit() in sighandlers; showkey: do not use exit-thru-sighandler

While at it, make ESC sequences more readable; and removed check for
isatty(stdin) in reset. Code shrink:

   text    data     bss     dec     hex filename
 884771     936   17216  902923   dc70b busybox_old
 884723     936   17216  902875   dc6db busybox_unstripped

Signed-off-by: Marek Polacek <mmpolacek@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/console-tools/reset.c b/console-tools/reset.c
index 7dffdea..1806ce7 100644 (file)
--- a/console-tools/reset.c
+++ b/console-tools/reset.c
@@ -8,11 +8,13 @@
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
-#include "libbb.h"
-
 /* BTW, which "standard" package has this utility? It doesn't seem
  * to be ncurses, coreutils, console-tools... then what? */
 
+#include "libbb.h"
+
+#define ESC "\033"
+
 #if ENABLE_STTY
 int stty_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 #endif
@@ -26,15 +28,15 @@ int reset_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
 
        /* no options, no getopt */
 
-       if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
+       if (/*isatty(STDIN_FILENO) &&*/ isatty(STDOUT_FILENO)) {
                /* See 'man 4 console_codes' for details:
                 * "ESC c"        -- Reset
                 * "ESC ( K"      -- Select user mapping
-                * "ESC [ J"      -- Erase to the end of screen
                 * "ESC [ 0 m"    -- Reset all display attributes
+                * "ESC [ J"      -- Erase to the end of screen
                 * "ESC [ ? 25 h" -- Make cursor visible
                 */
-               printf("\033c\033(K\033[J\033[0m\033[?25h");
+               printf(ESC"c" ESC"(K" ESC"[0m" ESC"[J" ESC"[?25h");
                /* http://bugs.busybox.net/view.php?id=1414:
                 * people want it to reset echo etc: */
 #if ENABLE_STTY

diff --git a/console-tools/resize.c b/console-tools/resize.c
index 12e50a1..fdfe2a6 100644 (file)
--- a/console-tools/resize.c
+++ b/console-tools/resize.c
@@ -17,7 +17,7 @@ static void
 onintr(int sig UNUSED_PARAM)
 {
        tcsetattr(STDERR_FILENO, TCSANOW, old_termios_p);
-       exit(EXIT_FAILURE);
+       _exit(EXIT_FAILURE);
 }
 
 int resize_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;

diff --git a/console-tools/showkey.c b/console-tools/showkey.c
index 149ea64..b29c84d 100644 (file)
--- a/console-tools/showkey.c
+++ b/console-tools/showkey.c
@@ -10,27 +10,7 @@
 #include "libbb.h"
 #include <linux/kd.h>
 
-// set raw tty mode
-// also used by microcom
-// libbb candidates?
-static void xget1(struct termios *t, struct termios *oldt)
-{
-       tcgetattr(STDIN_FILENO, oldt);
-       *t = *oldt;
-       cfmakeraw(t);
-}
-
-static void xset1(struct termios *tio)
-{
-       int ret = tcsetattr(STDIN_FILENO, TCSAFLUSH, tio);
-       if (ret) {
-               bb_perror_msg("can't tcsetattr for stdin");
-       }
-}
 
-/*
- * GLOBALS
- */
 struct globals {
        int kbmode;
        struct termios tio, tio0;
@@ -44,13 +24,22 @@ struct globals {
 } while (0)
 
 
-static void signal_handler(int signo)
+// set raw tty mode
+// also used by microcom
+// libbb candidates?
+static void xget1(struct termios *t, struct termios *oldt)
 {
-       // restore keyboard and console settings
-       xset1(&tio0);
-       xioctl(STDIN_FILENO, KDSKBMODE, (void *)(ptrdiff_t)kbmode);
-       // alarmed? -> exit 0
-       exit(SIGALRM == signo);
+       tcgetattr(STDIN_FILENO, oldt);
+       *t = *oldt;
+       cfmakeraw(t);
+}
+
+static void xset1(struct termios *t)
+{
+       int ret = tcsetattr(STDIN_FILENO, TCSAFLUSH, t);
+       if (ret) {
+               bb_perror_msg("can't tcsetattr for stdin");
+       }
 }
 
 int showkey_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
@@ -62,20 +51,21 @@ int showkey_main(int argc UNUSED_PARAM, char **argv)
                OPT_s = (1<<2), // display only the raw scan-codes
        };
 
+       INIT_G();
+
        // FIXME: aks are all mutually exclusive
        getopt32(argv, "aks");
 
-       INIT_G();
-
        // get keyboard settings
        xioctl(STDIN_FILENO, KDGKBMODE, &kbmode);
        printf("kb mode was %s\n\nPress any keys. Program terminates %s\n\n",
                kbmode == K_RAW ? "RAW" :
                        (kbmode == K_XLATE ? "XLATE" :
                                (kbmode == K_MEDIUMRAW ? "MEDIUMRAW" :
-                                       (kbmode == K_UNICODE ? "UNICODE" : "?UNKNOWN?")))
-               , (option_mask32 & OPT_a) ? "when CTRL+D pressed" : "10s after last keypress"
+                                       (kbmode == K_UNICODE ? "UNICODE" : "UNKNOWN")))
+               , (option_mask32 & OPT_a) ? "on EOF (ctrl-D)" : "10s after last keypress"
        );
+
        // prepare for raw mode
        xget1(&tio, &tio0);
        // put stdin in raw mode
@@ -83,34 +73,37 @@ int showkey_main(int argc UNUSED_PARAM, char **argv)
 
        if (option_mask32 & OPT_a) {
                unsigned char c;
+
                // just read stdin char by char
-               while (1 == safe_read(STDIN_FILENO, &c, 1)) {
+               while (1 == read(STDIN_FILENO, &c, 1)) {
                        printf("%3u 0%03o 0x%02x\r\n", c, c, c);
                        if (04 /*CTRL-D*/ == c)
                                break;
                }
        } else {
-               // we should exit on any signal
-               bb_signals(BB_FATAL_SIGS, signal_handler);
                // set raw keyboard mode
                xioctl(STDIN_FILENO, KDSKBMODE, (void *)(ptrdiff_t)((option_mask32 & OPT_k) ? K_MEDIUMRAW : K_RAW));
 
+               // we should exit on any signal; signals should interrupt read
+               bb_signals_recursive_norestart(BB_FATAL_SIGS, record_signo);
+
                // read and show scancodes
-               while (1) {
+               while (!bb_got_signal) {
                        char buf[18];
                        int i, n;
+
                        // setup 10s watchdog
                        alarm(10);
                        // read scancodes
                        n = read(STDIN_FILENO, buf, sizeof(buf));
                        i = 0;
                        while (i < n) {
-                               char c = buf[i];
-                               // show raw scancodes ordered? ->
                                if (option_mask32 & OPT_s) {
+                                       // show raw scancodes
                                        printf("0x%02x ", buf[i++]);
-                               // show interpreted scancodes (default) ? ->
                                } else {
+                                       // show interpreted scancodes (default)
+                                       char c = buf[i];
                                        int kc;
                                        if (i+2 < n
                                         && (c & 0x7f) == 0
@@ -130,9 +123,9 @@ int showkey_main(int argc UNUSED_PARAM, char **argv)
                }
        }
 
-       // cleanup
-       signal_handler(SIGALRM);
+       // restore keyboard and console settings
+       xset1(&tio0);
+       xioctl(STDIN_FILENO, KDSKBMODE, (void *)(ptrdiff_t)kbmode);
 
-       // should never be here!
        return EXIT_SUCCESS;
 }

diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index 066b569..68006ff 100644 (file)
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -94,8 +94,10 @@ static bool BB_ispunct(CHAR_T c) { return ((unsigned)c < 256 && ispunct(c)); }
 #endif
 
 
-#define SEQ_CLEAR_TILL_END_OF_SCREEN "\033[J"
-//#define SEQ_CLEAR_TILL_END_OF_LINE   "\033[K"
+#define ESC "\033"
+
+#define SEQ_CLEAR_TILL_END_OF_SCREEN  ESC"[J"
+//#define SEQ_CLEAR_TILL_END_OF_LINE  ESC"[K"
 
 
 enum {
@@ -446,7 +448,7 @@ static void input_backward(unsigned num)
                        } while (--num);
                        return;
                }
-               printf("\033[%uD", num);
+               printf(ESC"[%uD", num);
                return;
        }
 
@@ -471,7 +473,7 @@ static void input_backward(unsigned num)
                 */
                unsigned sv_cursor;
                /* go to 1st column; go up to first line */
-               printf("\r" "\033[%uA", cmdedit_y);
+               printf("\r" ESC"[%uA", cmdedit_y);
                cmdedit_y = 0;
                sv_cursor = cursor;
                put_prompt(); /* sets cursor to 0 */
@@ -488,12 +490,12 @@ static void input_backward(unsigned num)
                cmdedit_x = (width * cmdedit_y - num) % width;
                cmdedit_y -= lines_up;
                /* go to 1st column; go up */
-               printf("\r" "\033[%uA", lines_up);
+               printf("\r" ESC"[%uA", lines_up);
                /* go to correct column.
                 * xterm, konsole, Linux VT interpret 0 as 1 below! wow.
                 * need to *make sure* we skip it if cmdedit_x == 0 */
                if (cmdedit_x)
-                       printf("\033[%uC", cmdedit_x);
+                       printf(ESC"[%uC", cmdedit_x);
        }
 }
 
@@ -501,7 +503,7 @@ static void input_backward(unsigned num)
 static void redraw(int y, int back_cursor)
 {
        if (y > 0) /* up y lines */
-               printf("\033[%uA", y);
+               printf(ESC"[%uA", y);
        bb_putchar('\r');
        put_prompt();
        put_till_end_and_adv_cursor();
@@ -1626,7 +1628,7 @@ static void ask_terminal(void)
        pfd.events = POLLIN;
        if (safe_poll(&pfd, 1, 0) == 0) {
                S.sent_ESC_br6n = 1;
-               fputs("\033" "[6n", stdout);
+               fputs(ESC"[6n", stdout);
                fflush_all(); /* make terminal see it ASAP! */
        }
 }
@@ -2074,7 +2076,7 @@ int FAST_FUNC read_line_input(const char *prompt, char *command, int maxsize, li
                case CTRL('L'):
                vi_case(CTRL('L')|VI_CMDMODE_BIT:)
                        /* Control-l -- clear screen */
-                       printf("\033[H"); /* cursor to top,left */
+                       printf(ESC"[H"); /* cursor to top,left */
                        redraw(0, command_len - cursor);
                        break;
 #if MAX_HISTORY > 0

diff --git a/miscutils/conspy.c b/miscutils/conspy.c
index 01928b3..040fa86 100644 (file)
--- a/miscutils/conspy.c
+++ b/miscutils/conspy.c
@@ -43,6 +43,9 @@
 #include "libbb.h"
 #include <sys/kd.h>
 
+
+#define ESC "\033"
+
 struct screen_info {
        unsigned char lines, cols, cursor_x, cursor_y;
 };
@@ -70,7 +73,7 @@ struct globals {
        unsigned col;
        unsigned line;
        smallint curoff; // unknown:0 cursor on:-1 cursor off:1
-       char attrbuf[sizeof("\033[0;1;5;30;40m")];
+       char attrbuf[sizeof(ESC"[0;1;5;30;40m")];
        // remote console
        struct screen_info remote;
        // saved local tty terminfo
@@ -101,7 +104,7 @@ enum {
 static void clrscr(void)
 {
        // Home, clear till end of screen
-       fputs("\033[1;1H" "\033[J", stdout);
+       fputs(ESC"[1;1H" ESC"[J", stdout);
        G.col = G.line = 0;
 }
 
@@ -109,7 +112,7 @@ static void set_cursor(int state)
 {
        if (G.curoff != state) {
                G.curoff = state;
-               fputs("\033[?25", stdout);
+               fputs(ESC"[?25", stdout);
                bb_putchar("h?l"[1 + state]);
        }
 }
@@ -119,7 +122,7 @@ static void gotoxy(int col, int line)
        if (G.col != col || G.line != line) {
                G.col = col;
                G.line = line;
-               printf("\033[%u;%uH", line + 1, col + 1);
+               printf(ESC"[%u;%uH", line + 1, col + 1);
        }
 }
 
@@ -132,7 +135,7 @@ static void cleanup(int code)
        }
        // Reset attributes
        if (!BW)
-               fputs("\033[0m", stdout);
+               fputs(ESC"[0m", stdout);
        bb_putchar('\n');
        if (code > 1)
                kill_myself_with_sig(code);

diff --git a/miscutils/less.c b/miscutils/less.c
index 500059d..9e12c11 100644 (file)
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -28,13 +28,15 @@
 #include "xregex.h"
 #endif
 
+
+#define ESC "\033"
 /* The escape codes for highlighted and normal text */
-#define HIGHLIGHT   "\033[7m"
-#define NORMAL      "\033[0m"
+#define HIGHLIGHT   ESC"[7m"
+#define NORMAL      ESC"[0m"
 /* The escape code to home and clear to the end of screen */
-#define CLEAR       "\033[H\033[J"
+#define CLEAR       ESC"[H\033[J"
 /* The escape code to clear to the end of line */
-#define CLEAR_2_EOL "\033[K"
+#define CLEAR_2_EOL ESC"[K"
 
 enum {
 /* Absolute max of lines eaten */
@@ -165,12 +167,12 @@ static void set_tty_cooked(void)
    top-left corner of the console */
 static void move_cursor(int line, int row)
 {
-       printf("\033[%u;%uH", line, row);
+       printf(ESC"[%u;%uH", line, row);
 }
 
 static void clear_line(void)
 {
-       printf("\033[%u;0H" CLEAR_2_EOL, max_displayed_line + 2);
+       printf(ESC"[%u;0H" CLEAR_2_EOL, max_displayed_line + 2);
 }
 
 static void print_hilite(const char *str)

diff --git a/miscutils/watchdog.c b/miscutils/watchdog.c
index 36902a2..6307826 100644 (file)
--- a/miscutils/watchdog.c
+++ b/miscutils/watchdog.c
@@ -24,7 +24,7 @@ static void watchdog_shutdown(int sig UNUSED_PARAM)
        write(3, &V, 1);  /* Magic, see watchdog-api.txt in kernel */
        if (ENABLE_FEATURE_CLEAN_UP)
                close(3);
-       exit(EXIT_SUCCESS);
+       _exit(EXIT_SUCCESS);
 }
 
 int watchdog_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;

diff --git a/util-linux/more.c b/util-linux/more.c
index 1fd6f9e..788609a 100644 (file)
--- a/util-linux/more.c
+++ b/util-linux/more.c
@@ -29,16 +29,20 @@ struct globals {
 #define new_settings     (G.new_settings    )
 #define cin_fileno       (G.cin_fileno      )
 
-#define setTermSettings(fd, argp) do { \
-               if (ENABLE_FEATURE_USE_TERMIOS) tcsetattr(fd, TCSANOW, argp); \
-       } 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 gotsig(int sig UNUSED_PARAM)
 {
-       bb_putchar('\n');
+       /* bb_putchar_stderr doesn't use stdio buffering,
+        * therefore it is safe in signal handler */
+       bb_putchar_stderr('\n');
        setTermSettings(cin_fileno, &initial_settings);
-       exit(EXIT_FAILURE);
+       _exit(EXIT_FAILURE);
 }
 
 #define CONVERTED_TAB_SIZE 8