crond: code shrink

function                                             old     new   delta
crond_main                                          1431    1472     +41
fork_job                                             457     389     -68

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2010-07-08 16:12:10 +02:00
parent 45963c873c
commit 1f0ab1dc64

View File

@ -29,7 +29,7 @@
# define SENDMAIL "sendmail"
#endif
#ifndef SENDMAIL_ARGS
# define SENDMAIL_ARGS "-ti", NULL
# define SENDMAIL_ARGS "-ti"
#endif
#ifndef CRONUPDATE
# define CRONUPDATE "cron.update"
@ -53,9 +53,8 @@ typedef struct CronLine {
char *cl_cmd; /* shell command */
pid_t cl_pid; /* >0:running, <0:needs to be started in this minute, 0:dormant */
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
int cl_empty_mail_size; /* size of mail header only */
int cl_empty_mail_size; /* size of mail header only, 0 if no mailfile */
char *cl_mailto; /* whom to mail results, may be NULL */
smallint cl_mail_result; /* mail file is created, need to send it on completion */
#endif
/* ordered by size, not in natural order. makes code smaller: */
char cl_Dow[7]; /* 0-6, beginning sunday */
@ -536,13 +535,11 @@ static void change_user(struct passwd *pas)
// TODO: sendmail should be _run-time_ option, not compile-time!
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
//TODO: return pid (and stop passing line);
// stop passing mail_filename here but process it in caller
static void
fork_job(const char *user, CronLine *line, int mailFd,
const char *prog, const char *cmd, const char *arg,
const char *mail_filename)
{
static pid_t
fork_job(const char *user, int mailFd,
const char *prog,
const char *shell_cmd /* if NULL, we run sendmail */
) {
struct passwd *pas;
pid_t pid;
@ -563,37 +560,25 @@ fork_job(const char *user, CronLine *line, int mailFd,
crondlog(LVL5 "child running %s", prog);
}
if (mailFd >= 0) {
xmove_fd(mailFd, mail_filename ? 1 : 0);
xmove_fd(mailFd, shell_cmd ? 1 : 0);
dup2(1, 2);
}
/* crond 3.0pl1-100 puts tasks in separate process groups */
bb_setpgrp();
execlp(prog, prog, cmd, arg, (char *) NULL);
crondlog(ERR20 "can't exec, user %s cmd %s %s %s", user, prog, cmd, arg);
if (mail_filename) {
fdprintf(1, "Exec failed: %s -c %s\n", prog, arg);
execlp(prog, prog, (shell_cmd ? "-c" : SENDMAIL_ARGS), shell_cmd, (char *) NULL);
crondlog(ERR20 "can't execute '%s' for user %s", prog, user);
if (shell_cmd) {
fdprintf(1, "Exec failed: %s -c %s\n", prog, shell_cmd);
}
_exit(EXIT_SUCCESS);
}
line->cl_pid = pid;
if (pid < 0) {
/* FORK FAILED */
crondlog(ERR20 "can't vfork");
err:
line->cl_pid = 0;
if (mail_filename) {
unlink(mail_filename);
}
} else {
/* PARENT, FORK SUCCESS */
if (mail_filename) {
/* rename mail-file based on pid of process */
char *mailFile2 = xasprintf("%s/cron.%s.%d", TMPDIR, user, (int)pid);
rename(mail_filename, mailFile2); // TODO: xrename?
free(mailFile2);
}
}
pid = 0;
} /* else: PARENT, FORK SUCCESS */
/*
* Close the mail file descriptor.. we can't just leave it open in
@ -602,6 +587,7 @@ fork_job(const char *user, CronLine *line, int mailFd,
if (mailFd >= 0) {
close(mailFd);
}
return pid;
}
static void start_one_job(const char *user, CronLine *line)
@ -610,7 +596,7 @@ static void start_one_job(const char *user, CronLine *line)
int mailFd = -1;
line->cl_pid = 0;
line->cl_mail_result = 0;
line->cl_empty_mail_size = 0;
if (line->cl_mailto) {
/* Open mail file (owner is root so nobody can screw with it) */
@ -618,7 +604,6 @@ static void start_one_job(const char *user, CronLine *line)
mailFd = open(mailFile, O_CREAT | O_TRUNC | O_WRONLY | O_EXCL | O_APPEND, 0600);
if (mailFd >= 0) {
line->cl_mail_result = 1;
fdprintf(mailFd, "To: %s\nSubject: cron: %s\n\n", line->cl_mailto,
line->cl_cmd);
line->cl_empty_mail_size = lseek(mailFd, 0, SEEK_CUR);
@ -628,7 +613,17 @@ static void start_one_job(const char *user, CronLine *line)
}
}
fork_job(user, line, mailFd, DEFAULT_SHELL, "-c", line->cl_cmd, mailFile);
line->cl_pid = fork_job(user, mailFd, DEFAULT_SHELL, line->cl_cmd);
if (mailFd >= 0) {
if (line->cl_pid <= 0) {
unlink(mailFile);
} else {
/* rename mail-file based on pid of process */
char *mailFile2 = xasprintf("%s/cron.%s.%d", TMPDIR, user, (int)line->cl_pid);
rename(mailFile, mailFile2); // TODO: xrename?
free(mailFile2);
}
}
}
/*
@ -647,11 +642,10 @@ static void process_finished_job(const char *user, CronLine *line)
/* No job */
return;
}
if (line->cl_mail_result == 0) {
if (line->cl_empty_mail_size <= 0) {
/* End of job and no mail file, or end of sendmail job */
return;
}
line->cl_mail_result = 0;
/*
* End of primary job - check for mail file.
@ -673,8 +667,9 @@ static void process_finished_job(const char *user, CronLine *line)
close(mailFd);
return;
}
/* if (line->cl_mailto) - always true if cl_mail_result was true */
fork_job(user, line, mailFd, SENDMAIL, SENDMAIL_ARGS, NULL);
line->cl_empty_mail_size = 0;
/* if (line->cl_mailto) - always true if cl_empty_mail_size was nonzero */
line->cl_pid = fork_job(user, mailFd, SENDMAIL, NULL);
}
#else /* !ENABLE_FEATURE_CROND_CALL_SENDMAIL */