[src/trunk]: src/usr.bin/flock - use modern timer functions to handler fracti...

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/240ab87bdbc1
branches:  trunk
changeset: 782415:240ab87bdbc1
user:      christos <christos%NetBSD.org@localhost>
date:      Fri Nov 02 12:47:23 2012 +0000

description:
- use modern timer functions to handler fractional wait
- add a function to print the full command line
- use sigaction so signals interrupt us

diffstat:

 usr.bin/flock/flock.c |  72 +++++++++++++++++++++++++++++++++++++++++---------
 1 files changed, 58 insertions(+), 14 deletions(-)

diffs (143 lines):

diff -r a69eeb0e5dc9 -r 240ab87bdbc1 usr.bin/flock/flock.c
--- a/usr.bin/flock/flock.c     Fri Nov 02 12:24:52 2012 +0000
+++ b/usr.bin/flock/flock.c     Fri Nov 02 12:47:23 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: flock.c,v 1.4 2012/11/02 02:07:19 wiz Exp $    */
+/*     $NetBSD: flock.c,v 1.5 2012/11/02 12:47:23 christos Exp $       */
 
 /*-
  * Copyright (c) 2012 The NetBSD Foundation, Inc.
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: flock.c,v 1.4 2012/11/02 02:07:19 wiz Exp $");
+__RCSID("$NetBSD: flock.c,v 1.5 2012/11/02 12:47:23 christos Exp $");
 
 #include <stdio.h>
 #include <string.h>
@@ -43,6 +43,7 @@
 #include <errno.h>
 #include <getopt.h>
 #include <paths.h>
+#include <time.h>
 
 struct option flock_longopts[] = {
        { "debug",              no_argument,            0, 'd' },
@@ -65,9 +66,9 @@
 
 static __dead void usage(void) 
 {
-       fprintf(stderr, "Usage: %s [-dnosvx] [-w timeout] lockfile|lockdir [-c command]| "
-           "command ...\n\t%s [-dnsuvx] [-w timeout] lockfd\n", getprogname(),
-           getprogname());
+       fprintf(stderr, "Usage: %s [-dnosvx] [-w timeout] lockfile|lockdir "
+           "[-c command]|command ...\n\t%s [-dnsuvx] [-w timeout] lockfd\n",
+           getprogname(), getprogname());
        exit(EXIT_FAILURE);
 }
 
@@ -105,6 +106,21 @@
        }
 }
 
+static char *
+cmdline(char **av)
+{
+       char *v = NULL;
+       while (*av)
+               if (v) {
+                       if (asprintf(&v, "%s %s", v, *av++) < 0)
+                               err(EXIT_FAILURE, "malloc");
+               } else {
+                       if ((v = strdup(*av++)) == NULL)
+                               err(EXIT_FAILURE, "strdup");
+               }
+       return v;
+}
+
 int
 main(int argc, char *argv[])
 {
@@ -117,11 +133,12 @@
        char *mcargv[] = {
            __UNCONST(_PATH_BSHELL), __UNCONST("-c"), NULL, NULL
        };
-       char **cmdargv = NULL;
+       char **cmdargv = NULL, *v;
+       timer_t tm;
 
        setprogname(argv[0]);
 
-       while ((c = getopt_long(argc, argv, "+dnosuw:x", flock_longopts, NULL))
+       while ((c = getopt_long(argc, argv, "+dnosuvw:x", flock_longopts, NULL))
            != -1)
                switch (c) {
                case 'd':
@@ -182,17 +199,43 @@
                            (fd = open(argv[0], O_RDWR|O_CREAT, 0600)) == -1)
                                err(EXIT_FAILURE, "Cannot open `%s'", argv[0]);
                }
-               if (debug)
+               if (debug) {
                        fprintf(stderr, "file %s lock %s command %s ...\n",
-                           argv[0], lock2name(lock), cmdargv[0]);
+                           argv[0], lock2name(lock), v = cmdline(cmdargv));
+                       free(v);
+               }
                break;
        }
 
        if (timeout) {
-               signal(SIGALRM, sigalrm);
-               alarm((int)timeout);    // XXX: User timer_create()
+               struct sigevent ev;
+               struct itimerspec it;
+               struct sigaction sa;
+
+               timespecclear(&it.it_interval);
+               it.it_value.tv_sec = timeout;
+               it.it_value.tv_nsec = (timeout - it.it_value.tv_sec) *
+                       1000000000;
+
+               memset(&ev, 0, sizeof(ev));
+               ev.sigev_notify = SIGEV_SIGNAL;
+               ev.sigev_signo = SIGALRM;
+
+               if (timer_create(CLOCK_REALTIME, &ev, &tm) == -1)
+                       err(EXIT_FAILURE, "timer_create");
+
+               if (timer_settime(tm, TIMER_RELTIME, &it, NULL) == -1)
+                       err(EXIT_FAILURE, "timer_settime");
+
+               memset(&sa, 0, sizeof(sa));
+               sa.sa_handler = sigalrm;
+               sigemptyset(&sa.sa_mask);
+               sa.sa_flags = 0;
+               if (sigaction(SIGALRM, &sa, NULL) == -1)
+                       err(EXIT_FAILURE, "sigaction");
+
                if (debug)
-                       fprintf(stderr, "alarm %d\n", (int)timeout);
+                       fprintf(stderr, "alarm %g\n", timeout);
        }
 
        while (flock(fd, lock) == -1) {
@@ -205,14 +248,15 @@
        }
 
        if (timeout)
-               alarm(0);
+               timer_delete(tm);
 
        if (cls)
                (void)close(fd);
 
        if (cmdargv != NULL) {
                execvp(cmdargv[0], cmdargv);
-               err(EXIT_FAILURE, "execvp '%s'", cmdargv[0]);
+               err(EXIT_FAILURE, "execvp '%s'", v = cmdline(cmdargv));
+               free(v);
        }
        return 0;
 }