diff options
Diffstat (limited to 'usr.sbin/iostat/iostat.c')
| -rw-r--r-- | usr.sbin/iostat/iostat.c | 59 |
1 files changed, 57 insertions, 2 deletions
diff --git a/usr.sbin/iostat/iostat.c b/usr.sbin/iostat/iostat.c index 92b98e4..4db7991 100644 --- a/usr.sbin/iostat/iostat.c +++ b/usr.sbin/iostat/iostat.c @@ -110,6 +110,7 @@ #include <limits.h> #include <math.h> #include <nlist.h> +#include <signal.h> #include <stdio.h> #include <stdlib.h> #include <string.h> @@ -135,6 +136,8 @@ struct device_selection *dev_select; int maxshowdevs; volatile sig_atomic_t headercount; volatile sig_atomic_t wresized; /* Tty resized, when non-zero. */ +volatile sig_atomic_t alarm_rang; +volatile sig_atomic_t return_requested; unsigned short wrows; /* Current number of tty rows. */ int dflag = 0, Iflag = 0, Cflag = 0, Tflag = 0, oflag = 0, Kflag = 0; int xflag = 0, zflag = 0; @@ -143,6 +146,8 @@ int xflag = 0, zflag = 0; static void usage(void); static void needhdr(int signo); static void needresize(int signo); +static void needreturn(int signo); +static void alarm_clock(int signo); static void doresize(void); static void phdr(void); static void devstats(int perf_select, long double etime, int havelast); @@ -172,6 +177,7 @@ main(int argc, char **argv) int count = 0, waittime = 0; char *memf = NULL, *nlistf = NULL; struct devstat_match *matches; + struct itimerval alarmspec; int num_matches = 0; char errbuf[_POSIX2_LINE_MAX]; kvm_t *kd = NULL; @@ -442,10 +448,28 @@ main(int argc, char **argv) wrows = IOSTAT_DEFAULT_ROWS; } + /* + * Register a SIGINT handler so that we can print out final statistics + * when we get that signal + */ + (void)signal(SIGINT, needreturn); + + /* + * Register a SIGALRM handler to implement sleeps if the user uses the + * -c or -w options + */ + (void)signal(SIGALRM, alarm_clock); + alarmspec.it_interval.tv_sec = waittime / 1000; + alarmspec.it_interval.tv_usec = 1000 * (waittime % 1000); + alarmspec.it_value.tv_sec = waittime / 1000; + alarmspec.it_value.tv_usec = 1000 * (waittime % 1000); + setitimer(ITIMER_REAL, &alarmspec, NULL); + for (headercount = 1;;) { struct devinfo *tmp_dinfo; long tmp; long double etime; + sigset_t sigmask, oldsigmask; if (Tflag > 0) { if ((readvar(kd, "kern.tty_nin", X_TK_NIN, &cur.tk_nin, @@ -599,10 +623,23 @@ main(int argc, char **argv) } fflush(stdout); - if (count >= 0 && --count <= 0) + if ((count >= 0 && --count <= 0) || return_requested) break; - usleep(waittime * 1000); + /* + * Use sigsuspend to safely sleep until either signal is + * received + */ + alarm_rang = 0; + sigemptyset(&sigmask); + sigaddset(&sigmask, SIGINT); + sigaddset(&sigmask, SIGALRM); + sigprocmask(SIG_BLOCK, &sigmask, &oldsigmask); + while (! (alarm_rang || return_requested) ) { + sigsuspend(&oldsigmask); + } + sigprocmask(SIG_UNBLOCK, &sigmask, NULL); + havelast = 1; } @@ -633,6 +670,24 @@ needresize(int signo) } /* + * Record the alarm so the main loop can break its sleep + */ +void +alarm_clock(int signo) +{ + alarm_rang = 1; +} + +/* + * Request that the main loop exit soon + */ +void +needreturn(int signo) +{ + return_requested = 1; +} + +/* * Update the global `wrows' count of terminal rows. */ void |
