[hackers] [sbase] Audit time(1) || FRIGN

[git]

commit 382543fd5274f4b1c35fd177839c1e0cd90bb278
Author: FRIGN <d...@frign.de>
Date:   Thu Mar 5 00:23:09 2015 +0100

    Audit time(1)
    
    1) fix usage().
    2) sort includes and comment properly. rename rbeg and rend to r0 and r1.
    3) argc style and usage fixes.
    4) make error-messages clearer.
    5) BUGFIX: It was ignored when fork() failed.
    6) Don't call enprintf() after execvp and use _exit instead.

diff --git a/time.c b/time.c
index e4be7b4..fc17bf0 100644
--- a/time.c
+++ b/time.c
@@ -11,17 +11,17 @@
 static void
 usage(void)
 {
-       eprintf("usage: %s [-p] utility [argument ...]\n", argv0);
+       eprintf("usage: %s [-p] cmd [arg ...]\n", argv0);
 }
 
 int
 main(int argc, char *argv[])
 {
        pid_t pid;
-       struct tms tms; /* hold user and sys times */
-       clock_t rbeg, rend; /* real time */
-       long ticks; /* per second */
-       int status;
+       struct tms tms; /* user and sys times */
+       clock_t r0, r1; /* real time */
+       long ticks;     /* per second */
+       int status, savederrno;
 
        ARGBEGIN {
        case 'p':
@@ -30,26 +30,33 @@ main(int argc, char *argv[])
                usage();
        } ARGEND;
 
-       if (!*argv)
+       if (!argc)
                usage();
 
        if ((ticks = sysconf(_SC_CLK_TCK)) <= 0)
-               eprintf("sysconf() failed to retrieve clock ticks per 
second\n");
+               eprintf("sysconf _SC_CLK_TCK:");
 
-       if ((rbeg = times(&tms)) < 0)
-               eprintf("times() failed to retrieve start times:");
+       if ((r0 = times(&tms)) < 0)
+               eprintf("times:");
 
-       if (!(pid = fork())) { /* child */
-               execvp(*argv, argv);
-               enprintf(errno == ENOENT ? 127 : 126, "failed to exec %s:", 
*argv);
+       switch ((pid = fork())) {
+       case -1:
+               eprintf("fork:");
+       case 0:
+               execvp(argv[0], argv);
+               savederrno = errno;
+               weprintf("exec %s:", argv[0]);
+               _exit(126 + (savederrno == ENOENT));
+       default:
+               break;
        }
        waitpid(pid, &status, 0);
 
-       if ((rend = times(&tms)) < 0)
-               eprintf("times() failed to retrieve end times:");
+       if ((r1 = times(&tms)) < 0)
+               eprintf("times:");
 
        fprintf(stderr, "real %f\nuser %f\nsys %f\n",
-               (rend - rbeg)  / (double)ticks,
+               (r1 - r0)      / (double)ticks,
                tms.tms_cutime / (double)ticks,
                tms.tms_cstime / (double)ticks);