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crond: reorder functions to follow usual order: "main last"

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Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2010-07-08 04:07:15 +02:00
parent 9388b4e720
commit 4a09aefae2
1 changed files with 223 additions and 233 deletions
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448
miscutils/crond.c
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@ -17,25 +17,25 @@
/* glibc frees previous setenv'ed value when we do next setenv() /* glibc frees previous setenv'ed value when we do next setenv()
* of the same variable. uclibc does not do this! */ * of the same variable. uclibc does not do this! */
#if (defined(__GLIBC__) && !defined(__UCLIBC__)) /* || OTHER_SAFE_LIBC... */ #if (defined(__GLIBC__) && !defined(__UCLIBC__)) /* || OTHER_SAFE_LIBC... */
#define SETENV_LEAKS 0 # define SETENV_LEAKS 0
#else #else
#define SETENV_LEAKS 1 # define SETENV_LEAKS 1
#endif #endif
#define TMPDIR CONFIG_FEATURE_CROND_DIR #define TMPDIR CONFIG_FEATURE_CROND_DIR
#define CRONTABS CONFIG_FEATURE_CROND_DIR "/crontabs" #define CRONTABS CONFIG_FEATURE_CROND_DIR "/crontabs"
#ifndef SENDMAIL #ifndef SENDMAIL
#define SENDMAIL "sendmail" # define SENDMAIL "sendmail"
#endif #endif
#ifndef SENDMAIL_ARGS #ifndef SENDMAIL_ARGS
#define SENDMAIL_ARGS "-ti", NULL # define SENDMAIL_ARGS "-ti", NULL
#endif #endif
#ifndef CRONUPDATE #ifndef CRONUPDATE
#define CRONUPDATE "cron.update" # define CRONUPDATE "cron.update"
#endif #endif
#ifndef MAXLINES #ifndef MAXLINES
#define MAXLINES 256 /* max lines in non-root crontabs */ # define MAXLINES 256 /* max lines in non-root crontabs */
#endif #endif
@ -108,20 +108,6 @@ struct globals {
} while (0) } while (0)
static void CheckUpdates(void);
static void SynchronizeDir(void);
static int TestJobs(time_t t1, time_t t2);
static void RunJobs(void);
static int CheckJobs(void);
static void RunJob(const char *user, CronLine *line);
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
static void EndJob(const char *user, CronLine *line);
#else
#define EndJob(user, line) ((line)->cl_Pid = 0)
#endif
static void DeleteFile(const char *userName);
/* 0 is the most verbose, default 8 */ /* 0 is the most verbose, default 8 */
#define LVL5 "\x05" #define LVL5 "\x05"
#define LVL7 "\x07" #define LVL7 "\x07"
@ -163,101 +149,6 @@ static void crondlog(const char *ctl, ...)
exit(20); exit(20);
} }
int crond_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int crond_main(int argc UNUSED_PARAM, char **argv)
{
time_t t2;
int rescan;
int sleep_time;
unsigned opts;
INIT_G();
/* "-b after -f is ignored", and so on for every pair a-b */
opt_complementary = "f-b:b-f:S-L:L-S" IF_FEATURE_CROND_D(":d-l")
":l+:d+"; /* -l and -d have numeric param */
opts = getopt32(argv, "l:L:fbSc:" IF_FEATURE_CROND_D("d:"),
&LogLevel, &LogFile, &CDir
IF_FEATURE_CROND_D(,&LogLevel));
/* both -d N and -l N set the same variable: LogLevel */
if (!(opts & OPT_f)) {
/* close stdin, stdout, stderr.
* close unused descriptors - don't need them. */
bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
}
if (!(opts & OPT_d) && LogFile == NULL) {
/* logging to syslog */
openlog(applet_name, LOG_CONS | LOG_PID, LOG_CRON);
logmode = LOGMODE_SYSLOG;
}
xchdir(CDir);
//signal(SIGHUP, SIG_IGN); /* ? original crond dies on HUP... */
xsetenv("SHELL", DEFAULT_SHELL); /* once, for all future children */
crondlog(LVL8 "crond (busybox "BB_VER") started, log level %d", LogLevel);
SynchronizeDir();
write_pidfile("/var/run/crond.pid");
/* main loop - synchronize to 1 second after the minute, minimum sleep
* of 1 second. */
t2 = time(NULL);
rescan = 60;
sleep_time = 60;
for (;;) {
time_t t1;
long dt;
t1 = t2;
sleep((sleep_time + 1) - (time(NULL) % sleep_time));
t2 = time(NULL);
dt = (long)t2 - (long)t1;
/*
* The file 'cron.update' is checked to determine new cron
* jobs. The directory is rescanned once an hour to deal
* with any screwups.
*
* Check for time jump. Disparities over an hour either way
* result in resynchronization. A negative disparity
* less than an hour causes us to effectively sleep until we
* match the original time (i.e. no re-execution of jobs that
* have just been run). A positive disparity less than
* an hour causes intermediate jobs to be run, but only once
* in the worst case.
*
* When running jobs, the inequality used is greater but not
* equal to t1, and less then or equal to t2.
*/
if (--rescan == 0) {
rescan = 60;
SynchronizeDir();
}
CheckUpdates();
if (DebugOpt)
crondlog(LVL5 "wakeup dt=%ld", dt);
if (dt < -60 * 60 || dt > 60 * 60) {
crondlog(WARN9 "time disparity of %ld minutes detected", dt / 60);
/* and we do not run any jobs in this case */
} else if (dt > 0) {
/* Usual case: time advances forwad, as expected */
TestJobs(t1, t2);
RunJobs();
sleep(5);
if (CheckJobs() > 0) {
sleep_time = 10;
} else {
sleep_time = 60;
}
}
/* else: time jumped back, do not run any jobs */
} /* for (;;) */
return 0; /* not reached */
}
#if SETENV_LEAKS #if SETENV_LEAKS
/* We set environment *before* vfork (because we want to use vfork), /* We set environment *before* vfork (because we want to use vfork),
* so we cannot use setenv() - repeated calls to setenv() may leak memory! * so we cannot use setenv() - repeated calls to setenv() may leak memory!
@ -452,6 +343,48 @@ static void FixDayDow(CronLine *line)
} }
} }
/*
* DeleteFile() - delete user database
*
* Note: multiple entries for same user may exist if we were unable to
* completely delete a database due to running processes.
*/
static void DeleteFile(const char *userName)
{
CronFile **pfile = &FileBase;
CronFile *file;
while ((file = *pfile) != NULL) {
if (strcmp(userName, file->cf_User) == 0) {
CronLine **pline = &file->cf_LineBase;
CronLine *line;
file->cf_Running = 0;
file->cf_Deleted = 1;
while ((line = *pline) != NULL) {
if (line->cl_Pid > 0) {
file->cf_Running = 1;
pline = &line->cl_Next;
} else {
*pline = line->cl_Next;
free(line->cl_Shell);
free(line);
}
}
if (file->cf_Running == 0) {
*pfile = file->cf_Next;
free(file->cf_User);
free(file);
} else {
pfile = &file->cf_Next;
}
} else {
pfile = &file->cf_Next;
}
}
}
static void SynchronizeFile(const char *fileName) static void SynchronizeFile(const char *fileName)
{ {
struct parser_t *parser; struct parser_t *parser;
@ -600,51 +533,7 @@ static void SynchronizeDir(void)
} }
/* /*
* DeleteFile() - delete user database * Determine which jobs need to be run. Under normal conditions, the
*
* Note: multiple entries for same user may exist if we were unable to
* completely delete a database due to running processes.
*/
static void DeleteFile(const char *userName)
{
CronFile **pfile = &FileBase;
CronFile *file;
while ((file = *pfile) != NULL) {
if (strcmp(userName, file->cf_User) == 0) {
CronLine **pline = &file->cf_LineBase;
CronLine *line;
file->cf_Running = 0;
file->cf_Deleted = 1;
while ((line = *pline) != NULL) {
if (line->cl_Pid > 0) {
file->cf_Running = 1;
pline = &line->cl_Next;
} else {
*pline = line->cl_Next;
free(line->cl_Shell);
free(line);
}
}
if (file->cf_Running == 0) {
*pfile = file->cf_Next;
free(file->cf_User);
free(file);
} else {
pfile = &file->cf_Next;
}
} else {
pfile = &file->cf_Next;
}
}
}
/*
* TestJobs()
*
* determine which jobs need to be run. Under normal conditions, the
* period is about a minute (one scan). Worst case it will be one * period is about a minute (one scan). Worst case it will be one
* hour (60 scans). * hour (60 scans).
*/ */
@ -695,35 +584,63 @@ static int TestJobs(time_t t1, time_t t2)
return nJobs; return nJobs;
} }
static void RunJobs(void) #if ENABLE_FEATURE_CROND_CALL_SENDMAIL
static void
ForkJob(const char *user, CronLine *line, int mailFd,
const char *prog, const char *cmd, const char *arg,
const char *mail_filename);
/*
* EndJob - called when job terminates and when mail terminates
*/
static void EndJob(const char *user, CronLine *line)
{ {
CronFile *file; int mailFd;
CronLine *line; char mailFile[128];
struct stat sbuf;
for (file = FileBase; file; file = file->cf_Next) { /* No job */
if (!file->cf_Ready) if (line->cl_Pid <= 0) {
continue; line->cl_Pid = 0;
return;
}
file->cf_Ready = 0; /*
for (line = file->cf_LineBase; line; line = line->cl_Next) { * End of job and no mail file
if (line->cl_Pid >= 0) * End of sendmail job
continue; */
snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, line->cl_Pid);
line->cl_Pid = 0;
RunJob(file->cf_User, line); if (line->cl_MailFlag == 0) {
crondlog(LVL8 "USER %s pid %3d cmd %s", return;
file->cf_User, (int)line->cl_Pid, line->cl_Shell);
if (line->cl_Pid < 0) {
file->cf_Ready = 1;
} else if (line->cl_Pid > 0) {
file->cf_Running = 1;
} }
line->cl_MailFlag = 0;
/*
* End of primary job - check for mail file. If size has increased and
* the file is still valid, we sendmail it.
*/
mailFd = open(mailFile, O_RDONLY);
unlink(mailFile);
if (mailFd < 0) {
return;
} }
if (fstat(mailFd, &sbuf) < 0 || sbuf.st_uid != DaemonUid
|| sbuf.st_nlink != 0 || sbuf.st_size == line->cl_MailPos
|| !S_ISREG(sbuf.st_mode)
) {
close(mailFd);
return;
} }
if (line->cl_MailTo)
ForkJob(user, line, mailFd, SENDMAIL, SENDMAIL_ARGS, NULL);
} }
#else
# define EndJob(user, line) ((line)->cl_Pid = 0)
#endif
/* /*
* CheckJobs() - check for job completion
*
* Check for job completion, return number of jobs still running after * Check for job completion, return number of jobs still running after
* all done. * all done.
*/ */
@ -855,55 +772,7 @@ static void RunJob(const char *user, CronLine *line)
ForkJob(user, line, mailFd, DEFAULT_SHELL, "-c", line->cl_Shell, mailFile); ForkJob(user, line, mailFd, DEFAULT_SHELL, "-c", line->cl_Shell, mailFile);
} }
/* #else /* !ENABLE_FEATURE_CROND_CALL_SENDMAIL */
* EndJob - called when job terminates and when mail terminates
*/
static void EndJob(const char *user, CronLine *line)
{
int mailFd;
char mailFile[128];
struct stat sbuf;
/* No job */
if (line->cl_Pid <= 0) {
line->cl_Pid = 0;
return;
}
/*
* End of job and no mail file
* End of sendmail job
*/
snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, line->cl_Pid);
line->cl_Pid = 0;
if (line->cl_MailFlag == 0) {
return;
}
line->cl_MailFlag = 0;
/*
* End of primary job - check for mail file. If size has increased and
* the file is still valid, we sendmail it.
*/
mailFd = open(mailFile, O_RDONLY);
unlink(mailFile);
if (mailFd < 0) {
return;
}
if (fstat(mailFd, &sbuf) < 0 || sbuf.st_uid != DaemonUid
|| sbuf.st_nlink != 0 || sbuf.st_size == line->cl_MailPos
|| !S_ISREG(sbuf.st_mode)
) {
close(mailFd);
return;
}
if (line->cl_MailTo)
ForkJob(user, line, mailFd, SENDMAIL, SENDMAIL_ARGS, NULL);
}
#else /* crond without sendmail */
static void RunJob(const char *user, CronLine *line) static void RunJob(const char *user, CronLine *line)
{ {
@ -943,4 +812,125 @@ static void RunJob(const char *user, CronLine *line)
line->cl_Pid = pid; line->cl_Pid = pid;
} }
#endif /* ENABLE_FEATURE_CROND_CALL_SENDMAIL */ #endif /* !ENABLE_FEATURE_CROND_CALL_SENDMAIL */
static void RunJobs(void)
{
CronFile *file;
CronLine *line;
for (file = FileBase; file; file = file->cf_Next) {
if (!file->cf_Ready)
continue;
file->cf_Ready = 0;
for (line = file->cf_LineBase; line; line = line->cl_Next) {
if (line->cl_Pid >= 0)
continue;
RunJob(file->cf_User, line);
crondlog(LVL8 "USER %s pid %3d cmd %s",
file->cf_User, (int)line->cl_Pid, line->cl_Shell);
if (line->cl_Pid < 0) {
file->cf_Ready = 1;
} else if (line->cl_Pid > 0) {
file->cf_Running = 1;
}
}
}
}
int crond_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int crond_main(int argc UNUSED_PARAM, char **argv)
{
time_t t2;
int rescan;
int sleep_time;
unsigned opts;
INIT_G();
/* "-b after -f is ignored", and so on for every pair a-b */
opt_complementary = "f-b:b-f:S-L:L-S" IF_FEATURE_CROND_D(":d-l")
":l+:d+"; /* -l and -d have numeric param */
opts = getopt32(argv, "l:L:fbSc:" IF_FEATURE_CROND_D("d:"),
&LogLevel, &LogFile, &CDir
IF_FEATURE_CROND_D(,&LogLevel));
/* both -d N and -l N set the same variable: LogLevel */
if (!(opts & OPT_f)) {
/* close stdin, stdout, stderr.
* close unused descriptors - don't need them. */
bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
}
if (!(opts & OPT_d) && LogFile == NULL) {
/* logging to syslog */
openlog(applet_name, LOG_CONS | LOG_PID, LOG_CRON);
logmode = LOGMODE_SYSLOG;
}
xchdir(CDir);
//signal(SIGHUP, SIG_IGN); /* ? original crond dies on HUP... */
xsetenv("SHELL", DEFAULT_SHELL); /* once, for all future children */
crondlog(LVL8 "crond (busybox "BB_VER") started, log level %d", LogLevel);
SynchronizeDir();
write_pidfile("/var/run/crond.pid");
/* main loop - synchronize to 1 second after the minute, minimum sleep
* of 1 second. */
t2 = time(NULL);
rescan = 60;
sleep_time = 60;
for (;;) {
time_t t1;
long dt;
t1 = t2;
sleep((sleep_time + 1) - (time(NULL) % sleep_time));
t2 = time(NULL);
dt = (long)t2 - (long)t1;
/*
* The file 'cron.update' is checked to determine new cron
* jobs. The directory is rescanned once an hour to deal
* with any screwups.
*
* Check for time jump. Disparities over an hour either way
* result in resynchronization. A negative disparity
* less than an hour causes us to effectively sleep until we
* match the original time (i.e. no re-execution of jobs that
* have just been run). A positive disparity less than
* an hour causes intermediate jobs to be run, but only once
* in the worst case.
*
* When running jobs, the inequality used is greater but not
* equal to t1, and less then or equal to t2.
*/
if (--rescan == 0) {
rescan = 60;
SynchronizeDir();
}
CheckUpdates();
if (DebugOpt)
crondlog(LVL5 "wakeup dt=%ld", dt);
if (dt < -60 * 60 || dt > 60 * 60) {
crondlog(WARN9 "time disparity of %ld minutes detected", dt / 60);
/* and we do not run any jobs in this case */
} else if (dt > 0) {
/* Usual case: time advances forwad, as expected */
TestJobs(t1, t2);
RunJobs();
sleep(5);
if (CheckJobs() > 0) {
sleep_time = 10;
} else {
sleep_time = 60;
}
}
/* else: time jumped back, do not run any jobs */
} /* for (;;) */
return 0; /* not reached */
}