dnsd: fixes various segfaults.

[oweals/busybox.git] / libbb / bb_askpass.c

diff --git a/libbb/bb_askpass.c b/libbb/bb_askpass.c
index 435314ea029872f6975349b84bf2ae7b004a8ba2..3ad0e97cdd46b79e8f7a5242c109f0028176bb22 100644 (file)
--- a/libbb/bb_askpass.c
+++ b/libbb/bb_askpass.c
@@ -17,7 +17,7 @@ static void askpass_timeout(int ATTRIBUTE_UNUSED ignore)
 {
 }
 
-char *bb_askpass(int timeout, const char * prompt)
+char *bb_askpass(int timeout, const char *prompt)
 {
        /* Was static char[BIGNUM] */
        enum { sizeof_passwd = 128 };
@@ -25,35 +25,36 @@ char *bb_askpass(int timeout, const char * prompt)
 
        char *ret;
        int i;
-       struct sigaction sa;
-       struct termios old, new;
+       struct sigaction sa, oldsa;
+       struct termios tio, oldtio;
 
        if (!passwd)
                passwd = xmalloc(sizeof_passwd);
        memset(passwd, 0, sizeof_passwd);
 
-       tcgetattr(STDIN_FILENO, &old);
+       tcgetattr(STDIN_FILENO, &oldtio);
        tcflush(STDIN_FILENO, TCIFLUSH);
+       tio = oldtio;
+       tio.c_iflag &= ~(IUCLC|IXON|IXOFF|IXANY);
+       tio.c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL|TOSTOP);
+       tcsetattr(STDIN_FILENO, TCSANOW, &tio);
 
-       fputs(prompt, stdout);
-       fflush(stdout);
-
-       tcgetattr(STDIN_FILENO, &new);
-       new.c_iflag &= ~(IUCLC|IXON|IXOFF|IXANY);
-       new.c_lflag &= ~(ECHO|ECHOE|ECHOK|ECHONL|TOSTOP);
-       tcsetattr(STDIN_FILENO, TCSANOW, &new);
-
+       memset(&sa, 0, sizeof(sa));
+       /* sa.sa_flags = 0; - no SA_RESTART! */
+       /* SIGINT and SIGALRM will interrupt read below */
+       sa.sa_handler = askpass_timeout;
+       sigaction(SIGINT, &sa, &oldsa);
        if (timeout) {
-               sa.sa_flags = 0;
-               sa.sa_handler = askpass_timeout;
-               sigaction(SIGALRM, &sa, NULL);
+               sigaction_set(SIGALRM, &sa);
                alarm(timeout);
        }
 
+       fputs(prompt, stdout);
+       fflush(stdout);
        ret = NULL;
-       /* On timeout, read will hopefully be interrupted by SIGALRM,
+       /* On timeout or Ctrl-C, read will hopefully be interrupted,
         * and we return NULL */
-       if (read(STDIN_FILENO, passwd, sizeof_passwd-1) > 0) {
+       if (read(STDIN_FILENO, passwd, sizeof_passwd - 1) > 0) {
                ret = passwd;
                i = 0;
                /* Last byte is guaranteed to be 0
@@ -67,8 +68,9 @@ char *bb_askpass(int timeout, const char * prompt)
        if (timeout) {
                alarm(0);
        }
+       sigaction_set(SIGINT, &oldsa);
 
-       tcsetattr(STDIN_FILENO, TCSANOW, &old);
+       tcsetattr(STDIN_FILENO, TCSANOW, &oldtio);
        bb_putchar('\n');
        fflush(stdout);
        return ret;