mirror of
https://github.com/sheumann/hush.git
synced 2024-08-15 02:29:00 +00:00
Signed-off-by: Pere Orga <gotrunks@gmail.com> Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
954 lines
23 KiB
C
954 lines
23 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* crond -d[#] -c <crondir> -f -b
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*
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* run as root, but NOT setuid root
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*
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* Copyright 1994 Matthew Dillon (dillon@apollo.west.oic.com)
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* (version 2.3.2)
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* Vladimir Oleynik <dzo@simtreas.ru> (C) 2002
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*
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* Licensed under GPLv2 or later, see file LICENSE in this source tree.
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*/
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//usage:#define crond_trivial_usage
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//usage: "-fbS -l N " IF_FEATURE_CROND_D("-d N ") "-L LOGFILE -c DIR"
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//usage:#define crond_full_usage "\n\n"
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//usage: " -f Foreground"
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//usage: "\n -b Background (default)"
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//usage: "\n -S Log to syslog (default)"
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//usage: "\n -l Set log level. 0 is the most verbose, default 8"
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//usage: IF_FEATURE_CROND_D(
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//usage: "\n -d Set log level, log to stderr"
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//usage: )
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//usage: "\n -L Log to file"
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//usage: "\n -c Working dir"
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#include "libbb.h"
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#include <syslog.h>
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/* glibc frees previous setenv'ed value when we do next setenv()
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* of the same variable. uclibc does not do this! */
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#if (defined(__GLIBC__) && !defined(__UCLIBC__)) /* || OTHER_SAFE_LIBC... */
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# define SETENV_LEAKS 0
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#else
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# define SETENV_LEAKS 1
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#endif
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#define TMPDIR CONFIG_FEATURE_CROND_DIR
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#define CRONTABS CONFIG_FEATURE_CROND_DIR "/crontabs"
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#ifndef SENDMAIL
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# define SENDMAIL "sendmail"
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#endif
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#ifndef SENDMAIL_ARGS
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# define SENDMAIL_ARGS "-ti"
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#endif
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#ifndef CRONUPDATE
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# define CRONUPDATE "cron.update"
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#endif
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#ifndef MAXLINES
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# define MAXLINES 256 /* max lines in non-root crontabs */
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#endif
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typedef struct CronFile {
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struct CronFile *cf_next;
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struct CronLine *cf_lines;
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char *cf_username;
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smallint cf_wants_starting; /* bool: one or more jobs ready */
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smallint cf_has_running; /* bool: one or more jobs running */
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smallint cf_deleted; /* marked for deletion (but still has running jobs) */
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} CronFile;
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typedef struct CronLine {
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struct CronLine *cl_next;
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char *cl_cmd; /* shell command */
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pid_t cl_pid; /* >0:running, <0:needs to be started in this minute, 0:dormant */
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#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
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int cl_empty_mail_size; /* size of mail header only, 0 if no mailfile */
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char *cl_mailto; /* whom to mail results, may be NULL */
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#endif
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/* ordered by size, not in natural order. makes code smaller: */
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char cl_Dow[7]; /* 0-6, beginning sunday */
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char cl_Mons[12]; /* 0-11 */
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char cl_Hrs[24]; /* 0-23 */
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char cl_Days[32]; /* 1-31 */
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char cl_Mins[60]; /* 0-59 */
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} CronLine;
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#define DAEMON_UID 0
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enum {
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OPT_l = (1 << 0),
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OPT_L = (1 << 1),
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OPT_f = (1 << 2),
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OPT_b = (1 << 3),
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OPT_S = (1 << 4),
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OPT_c = (1 << 5),
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OPT_d = (1 << 6) * ENABLE_FEATURE_CROND_D,
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};
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#if ENABLE_FEATURE_CROND_D
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# define DebugOpt (option_mask32 & OPT_d)
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#else
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# define DebugOpt 0
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#endif
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struct globals {
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unsigned log_level; /* = 8; */
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time_t crontab_dir_mtime;
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const char *log_filename;
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const char *crontab_dir_name; /* = CRONTABS; */
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CronFile *cron_files;
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#if SETENV_LEAKS
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char *env_var_user;
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char *env_var_home;
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#endif
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} FIX_ALIASING;
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#define G (*(struct globals*)&bb_common_bufsiz1)
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#define INIT_G() do { \
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G.log_level = 8; \
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G.crontab_dir_name = CRONTABS; \
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} while (0)
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/* 0 is the most verbose, default 8 */
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#define LVL5 "\x05"
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#define LVL7 "\x07"
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#define LVL8 "\x08"
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#define WARN9 "\x49"
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#define DIE9 "\xc9"
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/* level >= 20 is "error" */
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#define ERR20 "\x14"
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static void crondlog(const char *ctl, ...) __attribute__ ((format (printf, 1, 2)));
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static void crondlog(const char *ctl, ...)
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{
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va_list va;
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int level = (ctl[0] & 0x1f);
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va_start(va, ctl);
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if (level >= (int)G.log_level) {
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/* Debug mode: all to (non-redirected) stderr, */
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/* Syslog mode: all to syslog (logmode = LOGMODE_SYSLOG), */
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if (!DebugOpt && G.log_filename) {
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/* Otherwise (log to file): we reopen log file at every write: */
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int logfd = open_or_warn(G.log_filename, O_WRONLY | O_CREAT | O_APPEND);
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if (logfd >= 0)
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xmove_fd(logfd, STDERR_FILENO);
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}
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/* When we log to syslog, level > 8 is logged at LOG_ERR
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* syslog level, level <= 8 is logged at LOG_INFO. */
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if (level > 8) {
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bb_verror_msg(ctl + 1, va, /* strerr: */ NULL);
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} else {
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char *msg = NULL;
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vasprintf(&msg, ctl + 1, va);
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bb_info_msg("%s: %s", applet_name, msg);
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free(msg);
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}
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}
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va_end(va);
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if (ctl[0] & 0x80)
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exit(20);
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}
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static const char DowAry[] ALIGN1 =
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"sun""mon""tue""wed""thu""fri""sat"
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/* "Sun""Mon""Tue""Wed""Thu""Fri""Sat" */
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;
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static const char MonAry[] ALIGN1 =
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"jan""feb""mar""apr""may""jun""jul""aug""sep""oct""nov""dec"
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/* "Jan""Feb""Mar""Apr""May""Jun""Jul""Aug""Sep""Oct""Nov""Dec" */
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;
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static void ParseField(char *user, char *ary, int modvalue, int off,
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const char *names, char *ptr)
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/* 'names' is a pointer to a set of 3-char abbreviations */
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{
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char *base = ptr;
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int n1 = -1;
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int n2 = -1;
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// this can't happen due to config_read()
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/*if (base == NULL)
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return;*/
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while (1) {
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int skip = 0;
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/* Handle numeric digit or symbol or '*' */
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if (*ptr == '*') {
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n1 = 0; /* everything will be filled */
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n2 = modvalue - 1;
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skip = 1;
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++ptr;
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} else if (isdigit(*ptr)) {
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char *endp;
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if (n1 < 0) {
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n1 = strtol(ptr, &endp, 10) + off;
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} else {
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n2 = strtol(ptr, &endp, 10) + off;
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}
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ptr = endp; /* gcc likes temp var for &endp */
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skip = 1;
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} else if (names) {
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int i;
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for (i = 0; names[i]; i += 3) {
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/* was using strncmp before... */
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if (strncasecmp(ptr, &names[i], 3) == 0) {
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ptr += 3;
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if (n1 < 0) {
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n1 = i / 3;
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} else {
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n2 = i / 3;
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}
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skip = 1;
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break;
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}
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}
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}
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/* handle optional range '-' */
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if (skip == 0) {
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goto err;
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}
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if (*ptr == '-' && n2 < 0) {
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++ptr;
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continue;
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}
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/*
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* collapse single-value ranges, handle skipmark, and fill
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* in the character array appropriately.
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*/
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if (n2 < 0) {
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n2 = n1;
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}
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if (*ptr == '/') {
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char *endp;
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skip = strtol(ptr + 1, &endp, 10);
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ptr = endp; /* gcc likes temp var for &endp */
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}
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/*
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* fill array, using a failsafe is the easiest way to prevent
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* an endless loop
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*/
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{
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int s0 = 1;
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int failsafe = 1024;
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--n1;
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do {
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n1 = (n1 + 1) % modvalue;
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if (--s0 == 0) {
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ary[n1 % modvalue] = 1;
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s0 = skip;
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}
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if (--failsafe == 0) {
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goto err;
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}
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} while (n1 != n2);
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}
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if (*ptr != ',') {
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break;
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}
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++ptr;
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n1 = -1;
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n2 = -1;
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}
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if (*ptr) {
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err:
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crondlog(WARN9 "user %s: parse error at %s", user, base);
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return;
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}
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if (DebugOpt && (G.log_level <= 5)) { /* like LVL5 */
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/* can't use crondlog, it inserts '\n' */
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int i;
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for (i = 0; i < modvalue; ++i)
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fprintf(stderr, "%d", (unsigned char)ary[i]);
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bb_putchar_stderr('\n');
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}
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}
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static void FixDayDow(CronLine *line)
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{
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unsigned i;
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int weekUsed = 0;
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int daysUsed = 0;
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for (i = 0; i < ARRAY_SIZE(line->cl_Dow); ++i) {
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if (line->cl_Dow[i] == 0) {
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weekUsed = 1;
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break;
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}
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}
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for (i = 0; i < ARRAY_SIZE(line->cl_Days); ++i) {
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if (line->cl_Days[i] == 0) {
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daysUsed = 1;
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break;
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}
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}
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if (weekUsed != daysUsed) {
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if (weekUsed)
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memset(line->cl_Days, 0, sizeof(line->cl_Days));
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else /* daysUsed */
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memset(line->cl_Dow, 0, sizeof(line->cl_Dow));
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}
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}
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/*
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* delete_cronfile() - delete user database
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*
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* Note: multiple entries for same user may exist if we were unable to
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* completely delete a database due to running processes.
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*/
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//FIXME: we will start a new job even if the old job is running
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//if crontab was reloaded: crond thinks that "new" job is different from "old"
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//even if they are in fact completely the same. Example
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//Crontab was:
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// 0-59 * * * * job1
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// 0-59 * * * * long_running_job2
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//User edits crontab to:
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// 0-59 * * * * job1_updated
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// 0-59 * * * * long_running_job2
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//Bug: crond can now start another long_running_job2 even if old one
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//is still running.
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//OTOH most other versions of cron do not wait for job termination anyway,
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//they end up with multiple copies of jobs if they don't terminate soon enough.
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static void delete_cronfile(const char *userName)
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{
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CronFile **pfile = &G.cron_files;
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CronFile *file;
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while ((file = *pfile) != NULL) {
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if (strcmp(userName, file->cf_username) == 0) {
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CronLine **pline = &file->cf_lines;
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CronLine *line;
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file->cf_has_running = 0;
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file->cf_deleted = 1;
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while ((line = *pline) != NULL) {
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if (line->cl_pid > 0) {
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file->cf_has_running = 1;
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pline = &line->cl_next;
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} else {
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*pline = line->cl_next;
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free(line->cl_cmd);
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free(line);
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}
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}
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if (file->cf_has_running == 0) {
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*pfile = file->cf_next;
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free(file->cf_username);
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free(file);
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continue;
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}
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}
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pfile = &file->cf_next;
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}
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}
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static void load_crontab(const char *fileName)
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{
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struct parser_t *parser;
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struct stat sbuf;
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int maxLines;
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char *tokens[6];
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#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
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char *mailTo = NULL;
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#endif
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delete_cronfile(fileName);
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if (!getpwnam(fileName)) {
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crondlog(LVL7 "ignoring file '%s' (no such user)", fileName);
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return;
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}
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parser = config_open(fileName);
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if (!parser)
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return;
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maxLines = (strcmp(fileName, "root") == 0) ? 65535 : MAXLINES;
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if (fstat(fileno(parser->fp), &sbuf) == 0 && sbuf.st_uid == DAEMON_UID) {
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CronFile *file = xzalloc(sizeof(CronFile));
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CronLine **pline;
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int n;
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file->cf_username = xstrdup(fileName);
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pline = &file->cf_lines;
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while (1) {
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CronLine *line;
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if (!--maxLines)
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break;
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n = config_read(parser, tokens, 6, 1, "# \t", PARSE_NORMAL | PARSE_KEEP_COPY);
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if (!n)
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break;
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if (DebugOpt)
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crondlog(LVL5 "user:%s entry:%s", fileName, parser->data);
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/* check if line is setting MAILTO= */
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if (0 == strncmp(tokens[0], "MAILTO=", 7)) {
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#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
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free(mailTo);
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mailTo = (tokens[0][7]) ? xstrdup(&tokens[0][7]) : NULL;
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#endif /* otherwise just ignore such lines */
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continue;
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}
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/* check if a minimum of tokens is specified */
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if (n < 6)
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continue;
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*pline = line = xzalloc(sizeof(*line));
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/* parse date ranges */
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ParseField(file->cf_username, line->cl_Mins, 60, 0, NULL, tokens[0]);
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ParseField(file->cf_username, line->cl_Hrs, 24, 0, NULL, tokens[1]);
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ParseField(file->cf_username, line->cl_Days, 32, 0, NULL, tokens[2]);
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ParseField(file->cf_username, line->cl_Mons, 12, -1, MonAry, tokens[3]);
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ParseField(file->cf_username, line->cl_Dow, 7, 0, DowAry, tokens[4]);
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/*
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* fix days and dow - if one is not "*" and the other
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* is "*", the other is set to 0, and vise-versa
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*/
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FixDayDow(line);
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#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
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/* copy mailto (can be NULL) */
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line->cl_mailto = xstrdup(mailTo);
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#endif
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/* copy command */
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line->cl_cmd = xstrdup(tokens[5]);
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if (DebugOpt) {
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crondlog(LVL5 " command:%s", tokens[5]);
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}
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pline = &line->cl_next;
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//bb_error_msg("M[%s]F[%s][%s][%s][%s][%s][%s]", mailTo, tokens[0], tokens[1], tokens[2], tokens[3], tokens[4], tokens[5]);
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}
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*pline = NULL;
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file->cf_next = G.cron_files;
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G.cron_files = file;
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if (maxLines == 0) {
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crondlog(WARN9 "user %s: too many lines", fileName);
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}
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}
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config_close(parser);
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}
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static void process_cron_update_file(void)
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{
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FILE *fi;
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char buf[256];
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fi = fopen_for_read(CRONUPDATE);
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if (fi != NULL) {
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unlink(CRONUPDATE);
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while (fgets(buf, sizeof(buf), fi) != NULL) {
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/* use first word only */
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skip_non_whitespace(buf)[0] = '\0';
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load_crontab(buf);
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}
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fclose(fi);
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}
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}
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static void rescan_crontab_dir(void)
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{
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CronFile *file;
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/* Delete all files until we only have ones with running jobs (or none) */
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again:
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for (file = G.cron_files; file; file = file->cf_next) {
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if (!file->cf_deleted) {
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delete_cronfile(file->cf_username);
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goto again;
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}
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}
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/* Remove cron update file */
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unlink(CRONUPDATE);
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/* Re-chdir, in case directory was renamed & deleted */
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if (chdir(G.crontab_dir_name) < 0) {
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crondlog(DIE9 "chdir(%s)", G.crontab_dir_name);
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}
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/* Scan directory and add associated users */
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{
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DIR *dir = opendir(".");
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struct dirent *den;
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if (!dir)
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crondlog(DIE9 "chdir(%s)", "."); /* exits */
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while ((den = readdir(dir)) != NULL) {
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if (strchr(den->d_name, '.') != NULL) {
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continue;
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}
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load_crontab(den->d_name);
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}
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closedir(dir);
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}
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}
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#if SETENV_LEAKS
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/* We set environment *before* vfork (because we want to use vfork),
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* so we cannot use setenv() - repeated calls to setenv() may leak memory!
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* Using putenv(), and freeing memory after unsetenv() won't leak */
|
|
static void safe_setenv(char **pvar_val, const char *var, const char *val)
|
|
{
|
|
char *var_val = *pvar_val;
|
|
|
|
if (var_val) {
|
|
bb_unsetenv_and_free(var_val);
|
|
}
|
|
*pvar_val = xasprintf("%s=%s", var, val);
|
|
putenv(*pvar_val);
|
|
}
|
|
#endif
|
|
|
|
static void set_env_vars(struct passwd *pas)
|
|
{
|
|
#if SETENV_LEAKS
|
|
safe_setenv(&G.env_var_user, "USER", pas->pw_name);
|
|
safe_setenv(&G.env_var_home, "HOME", pas->pw_dir);
|
|
/* if we want to set user's shell instead: */
|
|
/*safe_setenv(G.env_var_shell, "SHELL", pas->pw_shell);*/
|
|
#else
|
|
xsetenv("USER", pas->pw_name);
|
|
xsetenv("HOME", pas->pw_dir);
|
|
#endif
|
|
/* currently, we use constant one: */
|
|
/*setenv("SHELL", DEFAULT_SHELL, 1); - done earlier */
|
|
}
|
|
|
|
static void change_user(struct passwd *pas)
|
|
{
|
|
/* careful: we're after vfork! */
|
|
change_identity(pas); /* - initgroups, setgid, setuid */
|
|
if (chdir(pas->pw_dir) < 0) {
|
|
crondlog(WARN9 "chdir(%s)", pas->pw_dir);
|
|
if (chdir(TMPDIR) < 0) {
|
|
crondlog(DIE9 "chdir(%s)", TMPDIR); /* exits */
|
|
}
|
|
}
|
|
}
|
|
|
|
// TODO: sendmail should be _run-time_ option, not compile-time!
|
|
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
|
|
|
|
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;
|
|
|
|
/* prepare things before vfork */
|
|
pas = getpwnam(user);
|
|
if (!pas) {
|
|
crondlog(WARN9 "can't get uid for %s", user);
|
|
goto err;
|
|
}
|
|
set_env_vars(pas);
|
|
|
|
pid = vfork();
|
|
if (pid == 0) {
|
|
/* CHILD */
|
|
/* initgroups, setgid, setuid, and chdir to home or TMPDIR */
|
|
change_user(pas);
|
|
if (DebugOpt) {
|
|
crondlog(LVL5 "child running %s", prog);
|
|
}
|
|
if (mailFd >= 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, (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);
|
|
}
|
|
|
|
if (pid < 0) {
|
|
/* FORK FAILED */
|
|
crondlog(ERR20 "can't vfork");
|
|
err:
|
|
pid = 0;
|
|
} /* else: PARENT, FORK SUCCESS */
|
|
|
|
/*
|
|
* Close the mail file descriptor.. we can't just leave it open in
|
|
* a structure, closing it later, because we might run out of descriptors
|
|
*/
|
|
if (mailFd >= 0) {
|
|
close(mailFd);
|
|
}
|
|
return pid;
|
|
}
|
|
|
|
static void start_one_job(const char *user, CronLine *line)
|
|
{
|
|
char mailFile[128];
|
|
int mailFd = -1;
|
|
|
|
line->cl_pid = 0;
|
|
line->cl_empty_mail_size = 0;
|
|
|
|
if (line->cl_mailto) {
|
|
/* Open mail file (owner is root so nobody can screw with it) */
|
|
snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, getpid());
|
|
mailFd = open(mailFile, O_CREAT | O_TRUNC | O_WRONLY | O_EXCL | O_APPEND, 0600);
|
|
|
|
if (mailFd >= 0) {
|
|
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);
|
|
} else {
|
|
crondlog(ERR20 "can't create mail file %s for user %s, "
|
|
"discarding output", mailFile, user);
|
|
}
|
|
}
|
|
|
|
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);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* process_finished_job - called when job terminates and when mail terminates
|
|
*/
|
|
static void process_finished_job(const char *user, CronLine *line)
|
|
{
|
|
pid_t pid;
|
|
int mailFd;
|
|
char mailFile[128];
|
|
struct stat sbuf;
|
|
|
|
pid = line->cl_pid;
|
|
line->cl_pid = 0;
|
|
if (pid <= 0) {
|
|
/* No job */
|
|
return;
|
|
}
|
|
if (line->cl_empty_mail_size <= 0) {
|
|
/* End of job and no mail file, or end of sendmail job */
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* End of primary job - check for mail file.
|
|
* If size has changed and the file is still valid, we send it.
|
|
*/
|
|
snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, (int)pid);
|
|
mailFd = open(mailFile, O_RDONLY);
|
|
unlink(mailFile);
|
|
if (mailFd < 0) {
|
|
return;
|
|
}
|
|
|
|
if (fstat(mailFd, &sbuf) < 0
|
|
|| sbuf.st_uid != DAEMON_UID
|
|
|| sbuf.st_nlink != 0
|
|
|| sbuf.st_size == line->cl_empty_mail_size
|
|
|| !S_ISREG(sbuf.st_mode)
|
|
) {
|
|
close(mailFd);
|
|
return;
|
|
}
|
|
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 */
|
|
|
|
static void start_one_job(const char *user, CronLine *line)
|
|
{
|
|
struct passwd *pas;
|
|
pid_t pid;
|
|
|
|
pas = getpwnam(user);
|
|
if (!pas) {
|
|
crondlog(WARN9 "can't get uid for %s", user);
|
|
goto err;
|
|
}
|
|
|
|
/* Prepare things before vfork */
|
|
set_env_vars(pas);
|
|
|
|
/* Fork as the user in question and run program */
|
|
pid = vfork();
|
|
if (pid == 0) {
|
|
/* CHILD */
|
|
/* initgroups, setgid, setuid, and chdir to home or TMPDIR */
|
|
change_user(pas);
|
|
if (DebugOpt) {
|
|
crondlog(LVL5 "child running %s", DEFAULT_SHELL);
|
|
}
|
|
/* crond 3.0pl1-100 puts tasks in separate process groups */
|
|
bb_setpgrp();
|
|
execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", line->cl_cmd, (char *) NULL);
|
|
crondlog(ERR20 "can't execute '%s' for user %s", DEFAULT_SHELL, user);
|
|
_exit(EXIT_SUCCESS);
|
|
}
|
|
if (pid < 0) {
|
|
/* FORK FAILED */
|
|
crondlog(ERR20 "can't vfork");
|
|
err:
|
|
pid = 0;
|
|
}
|
|
line->cl_pid = pid;
|
|
}
|
|
|
|
#define process_finished_job(user, line) ((line)->cl_pid = 0)
|
|
|
|
#endif /* !ENABLE_FEATURE_CROND_CALL_SENDMAIL */
|
|
|
|
/*
|
|
* Determine which jobs need to be run. Under normal conditions, the
|
|
* period is about a minute (one scan). Worst case it will be one
|
|
* hour (60 scans).
|
|
*/
|
|
static void flag_starting_jobs(time_t t1, time_t t2)
|
|
{
|
|
time_t t;
|
|
|
|
/* Find jobs > t1 and <= t2 */
|
|
|
|
for (t = t1 - t1 % 60; t <= t2; t += 60) {
|
|
struct tm *ptm;
|
|
CronFile *file;
|
|
CronLine *line;
|
|
|
|
if (t <= t1)
|
|
continue;
|
|
|
|
ptm = localtime(&t);
|
|
for (file = G.cron_files; file; file = file->cf_next) {
|
|
if (DebugOpt)
|
|
crondlog(LVL5 "file %s:", file->cf_username);
|
|
if (file->cf_deleted)
|
|
continue;
|
|
for (line = file->cf_lines; line; line = line->cl_next) {
|
|
if (DebugOpt)
|
|
crondlog(LVL5 " line %s", line->cl_cmd);
|
|
if (line->cl_Mins[ptm->tm_min]
|
|
&& line->cl_Hrs[ptm->tm_hour]
|
|
&& (line->cl_Days[ptm->tm_mday] || line->cl_Dow[ptm->tm_wday])
|
|
&& line->cl_Mons[ptm->tm_mon]
|
|
) {
|
|
if (DebugOpt) {
|
|
crondlog(LVL5 " job: %d %s",
|
|
(int)line->cl_pid, line->cl_cmd);
|
|
}
|
|
if (line->cl_pid > 0) {
|
|
crondlog(LVL8 "user %s: process already running: %s",
|
|
file->cf_username, line->cl_cmd);
|
|
} else if (line->cl_pid == 0) {
|
|
line->cl_pid = -1;
|
|
file->cf_wants_starting = 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void start_jobs(void)
|
|
{
|
|
CronFile *file;
|
|
CronLine *line;
|
|
|
|
for (file = G.cron_files; file; file = file->cf_next) {
|
|
if (!file->cf_wants_starting)
|
|
continue;
|
|
|
|
file->cf_wants_starting = 0;
|
|
for (line = file->cf_lines; line; line = line->cl_next) {
|
|
pid_t pid;
|
|
if (line->cl_pid >= 0)
|
|
continue;
|
|
|
|
start_one_job(file->cf_username, line);
|
|
pid = line->cl_pid;
|
|
crondlog(LVL8 "USER %s pid %3d cmd %s",
|
|
file->cf_username, (int)pid, line->cl_cmd);
|
|
if (pid < 0) {
|
|
file->cf_wants_starting = 1;
|
|
}
|
|
if (pid > 0) {
|
|
file->cf_has_running = 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Check for job completion, return number of jobs still running after
|
|
* all done.
|
|
*/
|
|
static int check_completions(void)
|
|
{
|
|
CronFile *file;
|
|
CronLine *line;
|
|
int num_still_running = 0;
|
|
|
|
for (file = G.cron_files; file; file = file->cf_next) {
|
|
if (!file->cf_has_running)
|
|
continue;
|
|
|
|
file->cf_has_running = 0;
|
|
for (line = file->cf_lines; line; line = line->cl_next) {
|
|
int r;
|
|
|
|
if (line->cl_pid <= 0)
|
|
continue;
|
|
|
|
r = waitpid(line->cl_pid, NULL, WNOHANG);
|
|
if (r < 0 || r == line->cl_pid) {
|
|
process_finished_job(file->cf_username, line);
|
|
if (line->cl_pid == 0) {
|
|
/* sendmail was not started for it */
|
|
continue;
|
|
}
|
|
/* else: sendmail was started, job is still running, fall thru */
|
|
}
|
|
/* else: r == 0: "process is still running" */
|
|
file->cf_has_running = 1;
|
|
}
|
|
//FIXME: if !file->cf_has_running && file->deleted: delete it!
|
|
//otherwise deleted entries will stay forever, right?
|
|
num_still_running += file->cf_has_running;
|
|
}
|
|
return num_still_running;
|
|
}
|
|
|
|
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:"),
|
|
&G.log_level, &G.log_filename, &G.crontab_dir_name
|
|
IF_FEATURE_CROND_D(,&G.log_level));
|
|
/* both -d N and -l N set the same variable: G.log_level */
|
|
|
|
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) && G.log_filename == NULL) {
|
|
/* logging to syslog */
|
|
openlog(applet_name, LOG_CONS | LOG_PID, LOG_CRON);
|
|
logmode = LOGMODE_SYSLOG;
|
|
}
|
|
|
|
xchdir(G.crontab_dir_name);
|
|
//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", G.log_level);
|
|
rescan_crontab_dir();
|
|
write_pidfile("/var/run/crond.pid");
|
|
|
|
/* Main loop */
|
|
t2 = time(NULL);
|
|
rescan = 60;
|
|
sleep_time = 60;
|
|
for (;;) {
|
|
struct stat sbuf;
|
|
time_t t1;
|
|
long dt;
|
|
|
|
t1 = t2;
|
|
|
|
/* Synchronize to 1 minute, minimum 1 second */
|
|
sleep(sleep_time - (time(NULL) % sleep_time) + 1);
|
|
|
|
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 (stat(G.crontab_dir_name, &sbuf) != 0)
|
|
sbuf.st_mtime = 0; /* force update (once) if dir was deleted */
|
|
if (G.crontab_dir_mtime != sbuf.st_mtime) {
|
|
G.crontab_dir_mtime = sbuf.st_mtime;
|
|
rescan = 1;
|
|
}
|
|
if (--rescan == 0) {
|
|
rescan = 60;
|
|
rescan_crontab_dir();
|
|
}
|
|
process_cron_update_file();
|
|
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 forward, as expected */
|
|
flag_starting_jobs(t1, t2);
|
|
start_jobs();
|
|
if (check_completions() > 0) {
|
|
/* some jobs are still running */
|
|
sleep_time = 10;
|
|
} else {
|
|
sleep_time = 60;
|
|
}
|
|
}
|
|
/* else: time jumped back, do not run any jobs */
|
|
} /* for (;;) */
|
|
|
|
return 0; /* not reached */
|
|
}
|