Attachment 203979 Details for Bug 237538 – Add crontab support for -q (log suppression) and -n (mail suppression for successful run).

[patch] Add crontab support for -q (log suppression) and -n (mail suppression for successful run).

cron_command_options.patch (text/plain), 11.07 KB, created by Naveen Nathan on 2019-04-24 19:43:30 UTC

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Creator: Naveen Nathan

Created: 2019-04-24 19:43:30 UTC

Size: 11.07 KB

patch

obsolete

>diff --git a/usr.sbin/cron/cron/cron.h b/usr.sbin/cron/cron/cron.h
>index bb4f5287daea..f0f9e88d6b59 100644
>--- a/usr.sbin/cron/cron/cron.h
>+++ b/usr.sbin/cron/cron/cron.h
>@@ -191,6 +191,8 @@ typedef	struct _entry {
> #define	NOT_UNTIL	0x10
> #define	SEC_RES		0x20
> #define	INTERVAL	0x40
>+#define	DONT_LOG	0x80
>+#define	MAIL_WHEN_ERR	0x100
> 	time_t	lastrun;
> } entry;
> 
>@@ -257,7 +259,7 @@ user		*load_user(int, struct passwd *, char *),
> entry		*load_entry(FILE *, void (*)(char *),
> 				 struct passwd *, char **);
> 
>-FILE		*cron_popen(char *, char *, entry *);
>+FILE		*cron_popen(char *, char *, entry *, PID_T *);
> 
> 
> 				/* in the C tradition, we only create
>diff --git a/usr.sbin/cron/cron/do_command.c b/usr.sbin/cron/cron/do_command.c
>index 13d14e442a27..b54297c02cb2 100644
>--- a/usr.sbin/cron/cron/do_command.c
>+++ b/usr.sbin/cron/cron/do_command.c
>@@ -41,6 +41,7 @@ static const char rcsid[] =
> static void		child_process(entry *, user *),
> 			do_univ(user *);
> 
>+static WAIT_T		wait_on_child(PID_T, char *);
> 
> void
> do_command(e, u)
>@@ -94,7 +95,12 @@ child_process(e, u)
> 	int		stdin_pipe[2], stdout_pipe[2];
> 	register char	*input_data;
> 	char		*usernm, *mailto, *mailfrom;
>-	int		children = 0;
>+	PID_T		jobpid, stdinjob, mailpid;
>+
>+	register FILE	*mail;
>+	register int	bytes = 1;
>+	int		status = 0;
>+
> # if defined(LOGIN_CAP)
> 	struct passwd	*pwd;
> 	login_cap_t *lc;
>@@ -216,7 +222,8 @@ child_process(e, u)
> 
> 	/* fork again, this time so we can exec the user's command.
> 	 */
>-	switch (vfork()) {
>+
>+	switch (jobpid = vfork()) {
> 	case -1:
> 		log_it("CRON",getpid(),"error","can't vfork");
> 		exit(ERROR_EXIT);
>@@ -237,7 +244,7 @@ child_process(e, u)
> 		 * the actual user command shell was going to get and the
> 		 * PID is part of the log message.
> 		 */
>-		/*local*/{
>+		if ((e->flags & DONT_LOG) == 0) {
> 			char *x = mkprints((u_char *)e->cmd, strlen(e->cmd));
> 
> 			log_it(usernm, getpid(), "CMD", x);
>@@ -359,8 +366,6 @@ child_process(e, u)
> 		break;
> 	}
> 
>-	children++;
>-
> 	/* middle process, child of original cron, parent of process running
> 	 * the user's command.
> 	 */
>@@ -384,7 +389,9 @@ child_process(e, u)
> 	 * we would block here.  thus we must fork again.
> 	 */
> 
>-	if (*input_data && fork() == 0) {
>+	stdinjob = 0;
>+
>+	if (*input_data && (stdinjob = fork()) == 0) {
> 		register FILE	*out = fdopen(stdin_pipe[WRITE_PIPE], "w");
> 		register int	need_newline = FALSE;
> 		register int	escaped = FALSE;
>@@ -440,8 +447,6 @@ child_process(e, u)
> 	 */
> 	close(stdin_pipe[WRITE_PIPE]);
> 
>-	children++;
>-
> 	/*
> 	 * read output from the grandchild.  it's stderr has been redirected to
> 	 * it's stdout, which has been redirected to our pipe.  if there is any
>@@ -462,10 +467,6 @@ child_process(e, u)
> 
> 		ch = getc(in);
> 		if (ch != EOF) {
>-			register FILE	*mail;
>-			register int	bytes = 1;
>-			int		status = 0;
>-
> 			Debug(DPROC|DEXT,
> 				("[%d] got data (%x:%c) from grandchild\n",
> 					getpid(), ch, ch))
>@@ -500,7 +501,7 @@ child_process(e, u)
> 				hostname[sizeof(hostname) - 1] = '\0';
> 				(void) snprintf(mailcmd, sizeof(mailcmd),
> 					       MAILARGS, MAILCMD);
>-				if (!(mail = cron_popen(mailcmd, "w", e))) {
>+				if (!(mail = cron_popen(mailcmd, "w", e, &mailpid))) {
> 					warn("%s", MAILCMD);
> 					(void) _exit(ERROR_EXIT);
> 				}
>@@ -538,28 +539,54 @@ child_process(e, u)
> 				if (mailto)
> 					putc(ch, mail);
> 			}
>+		} /*if data from grandchild*/
> 
>-			/* only close pipe if we opened it -- i.e., we're
>-			 * mailing...
>-			 */
>+		Debug(DPROC, ("[%d] got EOF from grandchild\n", getpid()))
>+
>+		fclose(in);	/* also closes stdout_pipe[READ_PIPE] */
>+	}
>+
>+	/* wait for children to die.
>+	 */
>+	if (jobpid > 0) {
>+		WAIT_T	waiter;
>+
>+		waiter = wait_on_child(jobpid, "grandchild command job");
>+
>+		/* If everything went well, and -n was set, _and_ we have mail,
>+		 * we won't be mailing... so shoot the messenger!
>+		 */
>+		if (WIFEXITED(waiter) && WEXITSTATUS(waiter) == 0
>+		    && (e->flags & MAIL_WHEN_ERR) == MAIL_WHEN_ERR
>+		    && mailto) {
>+			Debug(DPROC, ("[%d] %s executed successful, mail suppressed\n",
>+				getpid(), "grandchild command job"))
>+			kill(mailpid, SIGKILL);
>+			(void)fclose(mail);
>+			mailto = NULL;
>+		}
> 
>-			if (mailto) {
>-				Debug(DPROC, ("[%d] closing pipe to mail\n",
>-					getpid()))
>-				/* Note: the pclose will probably see
>-				 * the termination of the grandchild
>-				 * in addition to the mail process, since
>-				 * it (the grandchild) is likely to exit
>-				 * after closing its stdout.
>-				 */
>-				status = cron_pclose(mail);
>-			}
>+
>+		/* only close pipe if we opened it -- i.e., we're
>+		 * mailing...
>+		 */
>+
>+		if (mailto) {
>+			Debug(DPROC, ("[%d] closing pipe to mail\n",
>+				getpid()))
>+			/* Note: the pclose will probably see
>+			 * the termination of the grandchild
>+			 * in addition to the mail process, since
>+			 * it (the grandchild) is likely to exit
>+			 * after closing its stdout.
>+			 */
>+			status = cron_pclose(mail);
> 
> 			/* if there was output and we could not mail it,
> 			 * log the facts so the poor user can figure out
> 			 * what's going on.
> 			 */
>-			if (mailto && status) {
>+			if (status) {
> 				char buf[MAX_TEMPSTR];
> 
> 				snprintf(buf, sizeof(buf),
>@@ -568,35 +595,38 @@ child_process(e, u)
> 					status);
> 				log_it(usernm, getpid(), "MAIL", buf);
> 			}
>+		}
>+	}
> 
>-		} /*if data from grandchild*/
>+	if (stdinjob > 0)
>+		wait_on_child(stdinjob, "grandchild stdinjob");
>+}
> 
>-		Debug(DPROC, ("[%d] got EOF from grandchild\n", getpid()))
>+static WAIT_T
>+wait_on_child(PID_T childpid, char *name) {
>+	WAIT_T	waiter;
>+	PID_T	pid;
> 
>-		fclose(in);	/* also closes stdout_pipe[READ_PIPE] */
>-	}
>+	Debug(DPROC, ("[%d] waiting for %s (%d) to finish\n",
>+		getpid(), name, childpid))
> 
>-	/* wait for children to die.
>-	 */
>-	for (;  children > 0;  children--)
>-	{
>-		WAIT_T		waiter;
>-		PID_T		pid;
>-
>-		Debug(DPROC, ("[%d] waiting for grandchild #%d to finish\n",
>-			getpid(), children))
>-		pid = wait(&waiter);
>-		if (pid < OK) {
>-			Debug(DPROC, ("[%d] no more grandchildren--mail written?\n",
>-				getpid()))
>-			break;
>-		}
>-		Debug(DPROC, ("[%d] grandchild #%d finished, status=%04x",
>-			getpid(), pid, WEXITSTATUS(waiter)))
>-		if (WIFSIGNALED(waiter) && WCOREDUMP(waiter))
>-			Debug(DPROC, (", dumped core"))
>-		Debug(DPROC, ("\n"))
>-	}
>+#ifdef POSIX
>+  	while ((pid = waitpid(childpid, &waiter, 0)) < 0 && errno == EINTR)
>+#else
>+  	while ((pid = wait4(childpid, &waiter, 0, NULL)) < 0 && errno == EINTR)
>+#endif
>+		;
>+
>+	if (pid < OK)
>+		return waiter;
>+
>+	Debug(DPROC, ("[%d] %s (%d) finished, status=%04x",
>+		getpid(), name, pid, WEXITSTATUS(waiter)))
>+	if (WIFSIGNALED(waiter) && WCOREDUMP(waiter))
>+		Debug(DPROC, (", dumped core"))
>+	Debug(DPROC, ("\n"))
>+
>+	return waiter;
> }
> 
> 
>diff --git a/usr.sbin/cron/cron/popen.c b/usr.sbin/cron/cron/popen.c
>index 01e62bf2bab2..73e6e28d748a 100644
>--- a/usr.sbin/cron/cron/popen.c
>+++ b/usr.sbin/cron/cron/popen.c
>@@ -55,9 +55,10 @@ static PID_T *pids;
> static int fds;
> 
> FILE *
>-cron_popen(program, type, e)
>+cron_popen(program, type, e, pidptr)
> 	char *program, *type;
> 	entry *e;
>+	PID_T *pidptr;
> {
> 	register char *cp;
> 	FILE *iop;
>@@ -218,6 +219,9 @@ cron_popen(program, type, e)
> 		free((char *)argv[argc]);
> 	}
> #endif
>+
>+	*pidptr = pid;
>+
> 	return(iop);
> }
> 
>diff --git a/usr.sbin/cron/crontab/crontab.5 b/usr.sbin/cron/crontab/crontab.5
>index 8988574f3745..354aba3dd8fb 100644
>--- a/usr.sbin/cron/crontab/crontab.5
>+++ b/usr.sbin/cron/crontab/crontab.5
>@@ -198,7 +198,8 @@ Ranges or
> lists of names are not allowed.
> .Pp
> The ``sixth'' field (the rest of the line) specifies the command to be
>-run.
>+run. One or more command options may precede the command to modify
>+processing behavior.
> The entire command portion of the line, up to a newline or %
> character, will be executed by
> .Pa /bin/sh
>@@ -211,6 +212,22 @@ Percent-signs (%) in the command, unless escaped with backslash
> after the first % will be sent to the command as standard
> input.
> .Pp
>+The following command options can be supplied:
>+.Bl -tag -width Ds
>+.It Fl n
>+No mail is sent after a successful run.
>+The execution output will only be mailed if the command exits with a non-zero
>+exit code.
>+The
>+.Fl n
>+option is an attempt to cure potentially copious volumes of mail coming from
>+.Xr cron 8 .
>+.It Fl q
>+Execution will not be logged.
>+.El
>+
>+Duplicate options are not allowed.
>+.Pp
> Note: The day of a command's execution can be specified by two
> fields \(em day of month, and day of week.
> If both fields are
>@@ -261,6 +278,10 @@ SHELL=/bin/sh
> # mail any output to `paul', no matter whose crontab this is
> MAILTO=paul
> #
>+# run every minute, suppress logging
>+* * * * *       -q date
>+# run every minute, suppress logging and mail
>+* * * * *       -q -n echo "no-op"
> # run five minutes after midnight, every day
> 5 0 * * *       $HOME/bin/daily.job >> $HOME/tmp/out 2>&1
> # run at 2:15pm on the first of every month -- output mailed to paul
>@@ -314,6 +335,12 @@ All of the
> .Sq @
> directives that can appear in place of the first five fields
> are extensions.
>+.Pp
>+Command processing can be modified using command options. The
>+.Sq -q
>+option suppresses logging. The
>+.Sq -n
>+option does not mail on successful run.
> .Sh AUTHORS
> .An Paul Vixie Aq Mt paul@vix.com
> .Sh BUGS
>diff --git a/usr.sbin/cron/lib/entry.c b/usr.sbin/cron/lib/entry.c
>index a8ec3ae8b568..a81a4ee78c30 100644
>--- a/usr.sbin/cron/lib/entry.c
>+++ b/usr.sbin/cron/lib/entry.c
>@@ -35,7 +35,8 @@ static const char rcsid[] =
> 
> typedef	enum ecode {
> 	e_none, e_minute, e_hour, e_dom, e_month, e_dow,
>-	e_cmd, e_timespec, e_username, e_group, e_mem
>+	e_cmd, e_timespec, e_username, e_group, e_option,
>+	e_mem
> #ifdef LOGIN_CAP
> 	, e_class
> #endif
>@@ -58,6 +59,7 @@ static char *ecodes[] =
> 		"bad time specifier",
> 		"bad username",
> 		"bad group name",
>+		"bad option",
> 		"out of memory",
> #ifdef LOGIN_CAP
> 		"bad class name",
>@@ -429,6 +431,53 @@ load_entry(file, error_func, pw, envp)
> 	}
> #endif
> 
>+	Debug(DPARS, ("load_entry()...checking for command options\n"))
>+
>+	ch = get_char(file);
>+
>+	while (ch == '-') {
>+		Debug(DPARS|DEXT, ("load_entry()...expecting option\n"))
>+		switch(ch = get_char(file)) {
>+		case 'n':
>+			Debug(DPARS|DEXT, ("load_entry()...got MAIL_WHEN_ERR ('n') option\n"))
>+			/* only allow the user to set the option once */
>+			if ((e->flags & MAIL_WHEN_ERR) == MAIL_WHEN_ERR) {
>+				Debug(DPARS|DEXT, ("load_entry()...duplicate MAIL_WHEN_ERR ('n') option\n"))
>+				ecode = e_option;
>+				goto eof;
>+			}
>+			e->flags |= MAIL_WHEN_ERR;
>+			break;
>+		case 'q':
>+			Debug(DPARS|DEXT, ("load_entry()...got DONT_LOG ('q') option\n"))
>+			/* only allow the user to set the option once */
>+			if ((e->flags & DONT_LOG) == DONT_LOG) {
>+				Debug(DPARS|DEXT, ("load_entry()...duplicate DONT_LOG ('q') option\n"))
>+				ecode = e_option;
>+				goto eof;
>+			}
>+			e->flags |= DONT_LOG;
>+			break;
>+		default:
>+			Debug(DPARS|DEXT, ("load_entry()...invalid option '%c'\n", ch))
>+			ecode = e_option;
>+			goto eof;
>+		}
>+		ch = get_char(file);
>+		if (ch!='\t' && ch!=' ') {
>+			ecode = e_option;
>+			goto eof;
>+		}
>+
>+		Skip_Blanks(ch, file)
>+		if (ch == EOF || ch == '\n') {
>+			ecode = e_cmd;
>+			goto eof;
>+		}
>+	}
>+
>+	unget_char(ch, file);
>+
> 	Debug(DPARS, ("load_entry()...about to parse command\n"))
> 
> 	/* Everything up to the next \n or EOF is part of the command...

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Attachments on bug 237538: 203978 | 203979 | 203994