kill: add support for real-time signals

Newly supported syntax for RT signals:

 RT<n>  		= SIGRTMIN + n
 RTMIN+<n>		= SIGRTMIN + n
 RTMAX-<n>		= SIGRTMAX - n

the final signal number has to be in interval [SIGRTMIN,SIGRTMAX].

Note that the "SIG" prefix is also supported for RT signals of course.

Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=676297
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/misc-utils/kill.c b/misc-utils/kill.c
index 61e61a321f1c617aea479d138362cb70b9cf96dc..e975d57ab1f80ff72b440bb3027aa25268eeb9f1 100644 (file)
--- a/misc-utils/kill.c
+++ b/misc-utils/kill.c
@@ -279,6 +279,35 @@ int main (int argc, char *argv[])
     return (errors);
 }
 
+#ifdef SIGRTMIN
+int rtsig_to_signum(char *sig)
+{
+       int num, maxi = 0;
+       char *ep = NULL;
+
+       if (strncasecmp(sig, "min+", 4) == 0)
+               sig += 4;
+       else if (strncasecmp(sig, "max-", 4) == 0) {
+               sig += 4;
+               maxi = 1;
+       }
+
+       if (!isdigit(*sig))
+               return -1;
+
+       errno = 0;
+       num = strtol(sig, &ep, 10);
+       if (!ep || sig == ep || errno || num < 0)
+               return -1;
+
+       num = maxi ? SIGRTMAX - num : SIGRTMIN + num;
+
+       if (num < SIGRTMIN || num > SIGRTMAX)
+               return -1;
+
+       return num;
+}
+#endif
 
 int signame_to_signum (char *sig)
 {
@@ -286,6 +315,13 @@ int signame_to_signum (char *sig)
 
     if (! strncasecmp (sig, "sig", 3))
        sig += 3;
+
+#ifdef SIGRTMIN
+    /* RT signals */
+    if (!strncasecmp(sig, "rt", 2))
+       return rtsig_to_signum(sig + 2);
+#endif
+    /* Normal sugnals */
     for (n = 0; n < ARRAY_SIZE(sys_signame); n++) {
        if (! strcasecmp (sys_signame[n].name, sig))
            return sys_signame[n].val;
@@ -343,6 +379,9 @@ void printsignals (FILE *fp)
        lpos += lth;
        fputs (sys_signame[n].name, fp);
     }
+#ifdef SIGRTMIN
+    fputs (" RT<N> RTMIN+<N> RTMAX-<N>", fp);
+#endif
     fputc ('\n', fp);
 }