From: Denys Vlasenko Date: Tue, 6 Jul 2010 16:47:00 +0000 (+0200) Subject: crond: code shrink X-Git-Tag: 1_18_0~444 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=d3c2b71ffae3f408e8e0e51b50a9f98e1b8b85e3;p=oweals%2Fbusybox.git crond: code shrink function old new delta ForkJob 513 457 -56 Signed-off-by: Denys Vlasenko --- diff --git a/miscutils/crond.c b/miscutils/crond.c index 4a3103cb9..49ecf745e 100644 --- a/miscutils/crond.c +++ b/miscutils/crond.c @@ -54,8 +54,8 @@ typedef struct CronLine { pid_t cl_Pid; /* running pid, 0, or armed (-1) */ #if ENABLE_FEATURE_CROND_CALL_SENDMAIL int cl_MailPos; /* 'empty file' size */ - smallint cl_MailFlag; /* running pid is for mail */ char *cl_MailTo; /* whom to mail results */ + smallint cl_MailFlag; /* running pid is for mail */ #endif /* ordered by size, not in natural order. makes code smaller: */ char cl_Dow[7]; /* 0-6, beginning sunday */ @@ -166,6 +166,9 @@ static void crondlog(const char *ctl, ...) 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(); @@ -195,62 +198,62 @@ int crond_main(int argc UNUSED_PARAM, char **argv) 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. */ - { - time_t t1 = time(NULL); - int rescan = 60; - int sleep_time = 60; + t2 = time(NULL); + rescan = 60; + sleep_time = 60; + for (;;) { + time_t t1; + long dt; - write_pidfile("/var/run/crond.pid"); - for (;;) { - time_t t2; - long dt; + t1 = t2; + sleep((sleep_time + 1) - (time(NULL) % sleep_time)); - sleep((sleep_time + 1) - (time(NULL) % sleep_time)); + t2 = time(NULL); + dt = (long)t2 - (long)t1; - 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 disparity. Disparities over an hour either way - * result in resynchronization. A reverse-indexed disparity - * less then 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 forward-indexed disparity less then - * 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); - } else if (dt > 0) { - TestJobs(t1, t2); - RunJobs(); - sleep(5); - if (CheckJobs() > 0) { - sleep_time = 10; - } else { - sleep_time = 60; - } + /* + * 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; } - t1 = t2; - } /* for (;;) */ - } + } + /* else: time jumped back, do not run any jobs */ + } /* for (;;) */ return 0; /* not reached */ } @@ -277,7 +280,7 @@ static void SetEnv(struct passwd *pas) safe_setenv(&env_var_user, "USER", pas->pw_name); safe_setenv(&env_var_home, "HOME", pas->pw_dir); /* if we want to set user's shell instead: */ - /*safe_setenv(env_var_user, "SHELL", pas->pw_shell);*/ + /*safe_setenv(env_var_shell, "SHELL", pas->pw_shell);*/ #else xsetenv("USER", pas->pw_name); xsetenv("HOME", pas->pw_dir); @@ -597,10 +600,10 @@ static void SynchronizeDir(void) } /* - * DeleteFile() - delete user database + * 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. + * 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) { @@ -806,14 +809,14 @@ ForkJob(const char *user, CronLine *line, int mailFd, if (mail_filename) { unlink(mail_filename); } - } else if (mail_filename) { - /* PARENT, FORK SUCCESS - * rename mail-file based on pid of process - */ - char mailFile2[128]; - - snprintf(mailFile2, sizeof(mailFile2), "%s/cron.%s.%d", TMPDIR, user, pid); - rename(mail_filename, mailFile2); // TODO: xrename? + } 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); + } } /*