* (version 2.3.2)
* Vladimir Oleynik <dzo@simtreas.ru> (C) 2002
*
- * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
+//usage:#define crond_trivial_usage
+//usage: "-fbS -l N " IF_FEATURE_CROND_D("-d N ") "-L LOGFILE -c DIR"
+//usage:#define crond_full_usage "\n\n"
+//usage: " -f Foreground"
+//usage: "\n -b Background (default)"
+//usage: "\n -S Log to syslog (default)"
+//usage: "\n -l Set log level. 0 is the most verbose, default 8"
+//usage: IF_FEATURE_CROND_D(
+//usage: "\n -d Set log level, log to stderr"
+//usage: )
+//usage: "\n -L Log to file"
+//usage: "\n -c Working dir"
+
#include "libbb.h"
#include <syslog.h>
/* glibc frees previous setenv'ed value when we do next setenv()
* of the same variable. uclibc does not do this! */
#if (defined(__GLIBC__) && !defined(__UCLIBC__)) /* || OTHER_SAFE_LIBC... */
-#define SETENV_LEAKS 0
+# define SETENV_LEAKS 0
#else
-#define SETENV_LEAKS 1
+# define SETENV_LEAKS 1
#endif
-#ifndef CRONTABS
-#define CRONTABS "/var/spool/cron/crontabs"
-#endif
-#ifndef TMPDIR
-#define TMPDIR "/var/spool/cron"
-#endif
+#define TMPDIR CONFIG_FEATURE_CROND_DIR
+#define CRONTABS CONFIG_FEATURE_CROND_DIR "/crontabs"
#ifndef SENDMAIL
-#define SENDMAIL "sendmail"
+# define SENDMAIL "sendmail"
#endif
#ifndef SENDMAIL_ARGS
-#define SENDMAIL_ARGS "-ti", "oem"
+# define SENDMAIL_ARGS "-ti"
#endif
#ifndef CRONUPDATE
-#define CRONUPDATE "cron.update"
+# define CRONUPDATE "cron.update"
#endif
#ifndef MAXLINES
-#define MAXLINES 256 /* max lines in non-root crontabs */
+# define MAXLINES 256 /* max lines in non-root crontabs */
#endif
typedef struct CronFile {
- struct CronFile *cf_Next;
- struct CronLine *cf_LineBase;
- char *cf_User; /* username */
- smallint cf_Ready; /* bool: one or more jobs ready */
- smallint cf_Running; /* bool: one or more jobs running */
- smallint cf_Deleted; /* marked for deletion, ignore */
+ struct CronFile *cf_next;
+ struct CronLine *cf_lines;
+ char *cf_username;
+ smallint cf_wants_starting; /* bool: one or more jobs ready */
+ smallint cf_has_running; /* bool: one or more jobs running */
+ smallint cf_deleted; /* marked for deletion (but still has running jobs) */
} CronFile;
typedef struct CronLine {
- struct CronLine *cl_Next;
- char *cl_Shell; /* shell command */
- pid_t cl_Pid; /* running pid, 0, or armed (-1) */
+ struct CronLine *cl_next;
+ 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_MailPos; /* 'empty file' size */
- smallint cl_MailFlag; /* running pid is for mail */
- char *cl_MailTo; /* whom to mail results */
+ int cl_empty_mail_size; /* size of mail header only, 0 if no mailfile */
+ char *cl_mailto; /* whom to mail results, may be NULL */
#endif
/* ordered by size, not in natural order. makes code smaller: */
- char cl_Dow[7]; /* 0-6, beginning sunday */
- char cl_Mons[12]; /* 0-11 */
- char cl_Hrs[24]; /* 0-23 */
- char cl_Days[32]; /* 1-31 */
- char cl_Mins[60]; /* 0-59 */
+ char cl_Dow[7]; /* 0-6, beginning sunday */
+ char cl_Mons[12]; /* 0-11 */
+ char cl_Hrs[24]; /* 0-23 */
+ char cl_Days[32]; /* 1-31 */
+ char cl_Mins[60]; /* 0-59 */
} CronLine;
-#define DaemonUid 0
+#define DAEMON_UID 0
enum {
OPT_b = (1 << 3),
OPT_S = (1 << 4),
OPT_c = (1 << 5),
- OPT_d = (1 << 6) * ENABLE_DEBUG_CROND_OPTION,
+ OPT_d = (1 << 6) * ENABLE_FEATURE_CROND_D,
};
-#if ENABLE_DEBUG_CROND_OPTION
-#define DebugOpt (option_mask32 & OPT_d)
+#if ENABLE_FEATURE_CROND_D
+# define DebugOpt (option_mask32 & OPT_d)
#else
-#define DebugOpt 0
+# define DebugOpt 0
#endif
struct globals {
- unsigned LogLevel; /* = 8; */
- const char *LogFile;
- const char *CDir; /* = CRONTABS; */
- CronFile *FileBase;
+ unsigned log_level; /* = 8; */
+ time_t crontab_dir_mtime;
+ const char *log_filename;
+ const char *crontab_dir_name; /* = CRONTABS; */
+ CronFile *cron_files;
#if SETENV_LEAKS
char *env_var_user;
char *env_var_home;
#endif
-};
+} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
-#define LogLevel (G.LogLevel )
-#define LogFile (G.LogFile )
-#define CDir (G.CDir )
-#define FileBase (G.FileBase )
-#define env_var_user (G.env_var_user )
-#define env_var_home (G.env_var_home )
#define INIT_G() do { \
- LogLevel = 8; \
- CDir = CRONTABS; \
+ G.log_level = 8; \
+ G.crontab_dir_name = CRONTABS; \
} 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 */
#define LVL5 "\x05"
#define LVL7 "\x07"
#define LVL8 "\x08"
-#define LVL9 "\x09"
#define WARN9 "\x49"
#define DIE9 "\xc9"
/* level >= 20 is "error" */
#define ERR20 "\x14"
+static void crondlog(const char *ctl, ...) __attribute__ ((format (printf, 1, 2)));
static void crondlog(const char *ctl, ...)
{
va_list va;
int level = (ctl[0] & 0x1f);
va_start(va, ctl);
- if (level >= (int)LogLevel) {
+ if (level >= (int)G.log_level) {
/* Debug mode: all to (non-redirected) stderr, */
/* Syslog mode: all to syslog (logmode = LOGMODE_SYSLOG), */
- if (!DebugOpt && LogFile) {
+ if (!DebugOpt && G.log_filename) {
/* Otherwise (log to file): we reopen log file at every write: */
- int logfd = open3_or_warn(LogFile, O_WRONLY | O_CREAT | O_APPEND, 0600);
+ int logfd = open_or_warn(G.log_filename, O_WRONLY | O_CREAT | O_APPEND);
if (logfd >= 0)
xmove_fd(logfd, STDERR_FILENO);
}
-// TODO: ERR -> error, WARN -> warning, LVL -> info
- bb_verror_msg(ctl + 1, va, /* strerr: */ NULL);
+ /* When we log to syslog, level > 8 is logged at LOG_ERR
+ * syslog level, level <= 8 is logged at LOG_INFO. */
+ if (level > 8) {
+ bb_verror_msg(ctl + 1, va, /* strerr: */ NULL);
+ } else {
+ char *msg = NULL;
+ vasprintf(&msg, ctl + 1, va);
+ bb_info_msg("%s: %s", applet_name, msg);
+ free(msg);
+ }
}
va_end(va);
if (ctl[0] & 0x80)
exit(20);
}
-int crond_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int crond_main(int argc UNUSED_PARAM, char **argv)
-{
- unsigned opt;
-
- 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" USE_DEBUG_CROND_OPTION(":d-l")
- ":l+:d+"; /* -l and -d have numeric param */
- opt = getopt32(argv, "l:L:fbSc:" USE_DEBUG_CROND_OPTION("d:"),
- &LogLevel, &LogFile, &CDir
- USE_DEBUG_CROND_OPTION(,&LogLevel));
- /* both -d N and -l N set the same variable: LogLevel */
-
- if (!(opt & OPT_f)) {
- /* close stdin, stdout, stderr.
- * close unused descriptors - don't need them. */
- bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
- }
-
- if (!DebugOpt && 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... */
- setenv("SHELL", DEFAULT_SHELL, 1); /* once, for all future children */
- crondlog(LVL9 "crond (busybox "BB_VER") started, log level %d", LogLevel);
- SynchronizeDir();
-
- /* main loop - synchronize to 1 second after the minute, minimum sleep
- * of 1 second. */
- {
- time_t t1 = time(NULL);
- time_t t2;
- long dt;
- int rescan = 60;
- int sleep_time = 60;
-
- write_pidfile("/var/run/crond.pid");
- for (;;) {
- 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 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 %d minutes detected", dt / 60);
- } else if (dt > 0) {
- TestJobs(t1, t2);
- RunJobs();
- sleep(5);
- if (CheckJobs() > 0) {
- sleep_time = 10;
- } else {
- sleep_time = 60;
- }
- }
- t1 = t2;
- }
- }
- return 0; /* not reached */
-}
-
-#if SETENV_LEAKS
-/* We set environment *before* vfork (because we want to use vfork),
- * so we cannot use setenv() - repeated calls to setenv() may leak memory!
- * Using putenv(), and freeing memory after unsetenv() won't leak */
-static void safe_setenv4(char **pvar_val, const char *var, const char *val /*, int len*/)
-{
- const int len = 4; /* both var names are 4 char long */
- char *var_val = *pvar_val;
-
- if (var_val) {
- var_val[len] = '\0'; /* nuke '=' */
- unsetenv(var_val);
- free(var_val);
- }
- *pvar_val = xasprintf("%s=%s", var, val);
- putenv(*pvar_val);
-}
-#endif
-
-static void SetEnv(struct passwd *pas)
-{
-#if SETENV_LEAKS
- safe_setenv4(&env_var_user, "USER", pas->pw_name);
- safe_setenv4(&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, 5);*/
-#else
- setenv("USER", pas->pw_name, 1);
- setenv("HOME", pas->pw_dir, 1);
-#endif
- /* currently, we use constant one: */
- /*setenv("SHELL", DEFAULT_SHELL, 1); - done earlier */
-}
-
-static void ChangeUser(struct passwd *pas)
-{
- /* careful: we're after vfork! */
- change_identity(pas); /* - initgroups, setgid, setuid */
- if (chdir(pas->pw_dir) < 0) {
- crondlog(LVL9 "can't chdir(%s)", pas->pw_dir);
- if (chdir(TMPDIR) < 0) {
- crondlog(DIE9 "can't chdir(%s)", TMPDIR); /* exits */
- }
- }
-}
-
static const char DowAry[] ALIGN1 =
"sun""mon""tue""wed""thu""fri""sat"
/* "Sun""Mon""Tue""Wed""Thu""Fri""Sat" */
/* Handle numeric digit or symbol or '*' */
if (*ptr == '*') {
- n1 = 0; /* everything will be filled */
+ n1 = 0; /* everything will be filled */
n2 = modvalue - 1;
skip = 1;
++ptr;
} else if (isdigit(*ptr)) {
+ char *endp;
if (n1 < 0) {
- n1 = strtol(ptr, &ptr, 10) + off;
+ n1 = strtol(ptr, &endp, 10) + off;
} else {
- n2 = strtol(ptr, &ptr, 10) + off;
+ n2 = strtol(ptr, &endp, 10) + off;
}
+ ptr = endp; /* gcc likes temp var for &endp */
skip = 1;
} else if (names) {
int i;
n2 = n1;
}
if (*ptr == '/') {
- skip = strtol(ptr + 1, &ptr, 10);
+ char *endp;
+ skip = strtol(ptr + 1, &endp, 10);
+ ptr = endp; /* gcc likes temp var for &endp */
}
/*
goto err;
}
} while (n1 != n2);
-
}
if (*ptr != ',') {
break;
return;
}
- if (DebugOpt && (LogLevel <= 5)) { /* like LVL5 */
+ if (DebugOpt && (G.log_level <= 5)) { /* like LVL5 */
/* can't use crondlog, it inserts '\n' */
int i;
for (i = 0; i < modvalue; ++i)
fprintf(stderr, "%d", (unsigned char)ary[i]);
- fputc('\n', stderr);
+ bb_putchar_stderr('\n');
}
}
}
}
-static void SynchronizeFile(const char *fileName)
+/*
+ * delete_cronfile() - delete user database
+ *
+ * Note: multiple entries for same user may exist if we were unable to
+ * completely delete a database due to running processes.
+ */
+//FIXME: we will start a new job even if the old job is running
+//if crontab was reloaded: crond thinks that "new" job is different from "old"
+//even if they are in fact completely the same. Example
+//Crontab was:
+// 0-59 * * * * job1
+// 0-59 * * * * long_running_job2
+//User edits crontab to:
+// 0-59 * * * * job1_updated
+// 0-59 * * * * long_running_job2
+//Bug: crond can now start another long_running_job2 even if old one
+//is still running.
+//OTOH most other versions of cron do not wait for job termination anyway,
+//they end up with multiple copies of jobs if they don't terminate soon enough.
+static void delete_cronfile(const char *userName)
+{
+ CronFile **pfile = &G.cron_files;
+ CronFile *file;
+
+ while ((file = *pfile) != NULL) {
+ if (strcmp(userName, file->cf_username) == 0) {
+ CronLine **pline = &file->cf_lines;
+ CronLine *line;
+
+ file->cf_has_running = 0;
+ file->cf_deleted = 1;
+
+ while ((line = *pline) != NULL) {
+ if (line->cl_pid > 0) {
+ file->cf_has_running = 1;
+ pline = &line->cl_next;
+ } else {
+ *pline = line->cl_next;
+ free(line->cl_cmd);
+ free(line);
+ }
+ }
+ if (file->cf_has_running == 0) {
+ *pfile = file->cf_next;
+ free(file->cf_username);
+ free(file);
+ continue;
+ }
+ }
+ pfile = &file->cf_next;
+ }
+}
+
+static void load_crontab(const char *fileName)
{
struct parser_t *parser;
struct stat sbuf;
char *mailTo = NULL;
#endif
- if (!fileName)
+ delete_cronfile(fileName);
+
+ if (!getpwnam(fileName)) {
+ crondlog(LVL7 "ignoring file '%s' (no such user)", fileName);
return;
+ }
- DeleteFile(fileName);
parser = config_open(fileName);
if (!parser)
return;
maxLines = (strcmp(fileName, "root") == 0) ? 65535 : MAXLINES;
- if (fstat(fileno(parser->fp), &sbuf) == 0 && sbuf.st_uid == DaemonUid) {
+ if (fstat(fileno(parser->fp), &sbuf) == 0 && sbuf.st_uid == DAEMON_UID) {
CronFile *file = xzalloc(sizeof(CronFile));
CronLine **pline;
int n;
- file->cf_User = xstrdup(fileName);
- pline = &file->cf_LineBase;
+ file->cf_username = xstrdup(fileName);
+ pline = &file->cf_lines;
- while (--maxLines
- && (n = config_read(parser, tokens, 6, 1, "# \t", PARSE_LAST_IS_GREEDY|PARSE_KEEP_COPY))
- ) {
+ while (1) {
CronLine *line;
+ if (!--maxLines)
+ break;
+ n = config_read(parser, tokens, 6, 1, "# \t", PARSE_NORMAL | PARSE_KEEP_COPY);
+ if (!n)
+ break;
+
if (DebugOpt)
crondlog(LVL5 "user:%s entry:%s", fileName, parser->data);
/* check if a minimum of tokens is specified */
if (n < 6)
continue;
- *pline = line = xzalloc(sizeof(CronLine));
+ *pline = line = xzalloc(sizeof(*line));
/* parse date ranges */
- ParseField(file->cf_User, line->cl_Mins, 60, 0, NULL, tokens[0]);
- ParseField(file->cf_User, line->cl_Hrs, 24, 0, NULL, tokens[1]);
- ParseField(file->cf_User, line->cl_Days, 32, 0, NULL, tokens[2]);
- ParseField(file->cf_User, line->cl_Mons, 12, -1, MonAry, tokens[3]);
- ParseField(file->cf_User, line->cl_Dow, 7, 0, DowAry, tokens[4]);
+ ParseField(file->cf_username, line->cl_Mins, 60, 0, NULL, tokens[0]);
+ ParseField(file->cf_username, line->cl_Hrs, 24, 0, NULL, tokens[1]);
+ ParseField(file->cf_username, line->cl_Days, 32, 0, NULL, tokens[2]);
+ ParseField(file->cf_username, line->cl_Mons, 12, -1, MonAry, tokens[3]);
+ ParseField(file->cf_username, line->cl_Dow, 7, 0, DowAry, tokens[4]);
/*
* fix days and dow - if one is not "*" and the other
* is "*", the other is set to 0, and vise-versa
FixDayDow(line);
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
/* copy mailto (can be NULL) */
- line->cl_MailTo = xstrdup(mailTo);
+ line->cl_mailto = xstrdup(mailTo);
#endif
/* copy command */
- line->cl_Shell = xstrdup(tokens[5]);
+ line->cl_cmd = xstrdup(tokens[5]);
if (DebugOpt) {
crondlog(LVL5 " command:%s", tokens[5]);
}
- pline = &line->cl_Next;
+ pline = &line->cl_next;
//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]);
}
*pline = NULL;
- file->cf_Next = FileBase;
- FileBase = file;
+ file->cf_next = G.cron_files;
+ G.cron_files = file;
if (maxLines == 0) {
crondlog(WARN9 "user %s: too many lines", fileName);
config_close(parser);
}
-static void CheckUpdates(void)
+static void process_cron_update_file(void)
{
FILE *fi;
char buf[256];
unlink(CRONUPDATE);
while (fgets(buf, sizeof(buf), fi) != NULL) {
/* use first word only */
- SynchronizeFile(strtok(buf, " \t\r\n"));
+ skip_non_whitespace(buf)[0] = '\0';
+ load_crontab(buf);
}
fclose(fi);
}
}
-static void SynchronizeDir(void)
+static void rescan_crontab_dir(void)
{
CronFile *file;
- /* Attempt to delete the database. */
+
+ /* Delete all files until we only have ones with running jobs (or none) */
again:
- for (file = FileBase; file; file = file->cf_Next) {
- if (!file->cf_Deleted) {
- DeleteFile(file->cf_User);
+ for (file = G.cron_files; file; file = file->cf_next) {
+ if (!file->cf_deleted) {
+ delete_cronfile(file->cf_username);
goto again;
}
}
- /*
- * Remove cron update file
- *
- * Re-chdir, in case directory was renamed & deleted, or otherwise
- * screwed up.
- *
- * scan directory and add associated users
- */
+ /* Remove cron update file */
unlink(CRONUPDATE);
- if (chdir(CDir) < 0) {
- crondlog(DIE9 "can't chdir(%s)", CDir);
+ /* Re-chdir, in case directory was renamed & deleted */
+ if (chdir(G.crontab_dir_name) < 0) {
+ crondlog(DIE9 "chdir(%s)", G.crontab_dir_name);
}
+
+ /* Scan directory and add associated users */
{
DIR *dir = opendir(".");
struct dirent *den;
if (!dir)
- crondlog(DIE9 "can't chdir(%s)", "."); /* exits */
+ crondlog(DIE9 "chdir(%s)", "."); /* exits */
while ((den = readdir(dir)) != NULL) {
if (strchr(den->d_name, '.') != NULL) {
continue;
}
- if (getpwnam(den->d_name)) {
- SynchronizeFile(den->d_name);
- } else {
- crondlog(LVL7 "ignoring %s", den->d_name);
- }
+ load_crontab(den->d_name);
}
closedir(dir);
}
}
-/*
- * 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;
- }
- }
-}
-
-/*
- * 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
- * hour (60 scans).
- */
-static int TestJobs(time_t t1, time_t t2)
+#if SETENV_LEAKS
+/* We set environment *before* vfork (because we want to use vfork),
+ * so we cannot use setenv() - repeated calls to setenv() may leak memory!
+ * Using putenv(), and freeing memory after unsetenv() won't leak */
+static void safe_setenv(char **pvar_val, const char *var, const char *val)
{
- int nJobs = 0;
- time_t t;
-
- /* Find jobs > t1 and <= t2 */
-
- for (t = t1 - t1 % 60; t <= t2; t += 60) {
- struct tm *tp;
- CronFile *file;
- CronLine *line;
-
- if (t <= t1)
- continue;
+ char *var_val = *pvar_val;
- tp = localtime(&t);
- for (file = FileBase; file; file = file->cf_Next) {
- if (DebugOpt)
- crondlog(LVL5 "file %s:", file->cf_User);
- if (file->cf_Deleted)
- continue;
- for (line = file->cf_LineBase; line; line = line->cl_Next) {
- if (DebugOpt)
- crondlog(LVL5 " line %s", line->cl_Shell);
- if (line->cl_Mins[tp->tm_min] && line->cl_Hrs[tp->tm_hour]
- && (line->cl_Days[tp->tm_mday] || line->cl_Dow[tp->tm_wday])
- && line->cl_Mons[tp->tm_mon]
- ) {
- if (DebugOpt) {
- crondlog(LVL5 " job: %d %s",
- (int)line->cl_Pid, line->cl_Shell);
- }
- if (line->cl_Pid > 0) {
- crondlog(LVL8 "user %s: process already running: %s",
- file->cf_User, line->cl_Shell);
- } else if (line->cl_Pid == 0) {
- line->cl_Pid = -1;
- file->cf_Ready = 1;
- ++nJobs;
- }
- }
- }
- }
+ if (var_val) {
+ bb_unsetenv_and_free(var_val);
}
- return nJobs;
+ *pvar_val = xasprintf("%s=%s", var, val);
+ putenv(*pvar_val);
}
+#endif
-static void RunJobs(void)
+static void set_env_vars(struct passwd *pas)
{
- 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;
- }
- }
- }
+#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 */
}
-/*
- * CheckJobs() - check for job completion
- *
- * Check for job completion, return number of jobs still running after
- * all done.
- */
-static int CheckJobs(void)
+static void change_user(struct passwd *pas)
{
- CronFile *file;
- CronLine *line;
- int nStillRunning = 0;
-
- for (file = FileBase; file; file = file->cf_Next) {
- if (file->cf_Running) {
- file->cf_Running = 0;
-
- for (line = file->cf_LineBase; line; line = line->cl_Next) {
- int status, r;
- if (line->cl_Pid <= 0)
- continue;
-
- r = waitpid(line->cl_Pid, &status, WNOHANG);
- if (r < 0 || r == line->cl_Pid) {
- EndJob(file->cf_User, line);
- if (line->cl_Pid) {
- file->cf_Running = 1;
- }
- } else if (r == 0) {
- file->cf_Running = 1;
- }
- }
+ /* 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 */
}
- nStillRunning += file->cf_Running;
}
- return nStillRunning;
}
-#if ENABLE_FEATURE_CROND_CALL_SENDMAIL
-
// TODO: sendmail should be _run-time_ option, not compile-time!
+#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)
-{
+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(LVL9 "can't get uid for %s", user);
+ crondlog(WARN9 "can't get uid for %s", user);
goto err;
}
- SetEnv(pas);
+ set_env_vars(pas);
pid = vfork();
if (pid == 0) {
/* CHILD */
- /* change running state to the user in question */
- ChangeUser(pas);
+ /* 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, mail_filename ? 1 : 0);
+ xmove_fd(mailFd, shell_cmd ? 1 : 0);
dup2(1, 2);
}
- execlp(prog, prog, cmd, arg, 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);
+ /* 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);
}
- 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 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?
- }
+ pid = 0;
+ } /* else: PARENT, FORK SUCCESS */
/*
* Close the mail file descriptor.. we can't just leave it open in
if (mailFd >= 0) {
close(mailFd);
}
+ return pid;
}
-static void RunJob(const char *user, CronLine *line)
+static void start_one_job(const char *user, CronLine *line)
{
char mailFile[128];
int mailFd = -1;
- line->cl_Pid = 0;
- line->cl_MailFlag = 0;
+ line->cl_pid = 0;
+ line->cl_empty_mail_size = 0;
- if (line->cl_MailTo) {
- /* open mail file - owner root so nobody can screw with it. */
+ 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) {
- line->cl_MailFlag = 1;
- fdprintf(mailFd, "To: %s\nSubject: cron: %s\n\n", line->cl_MailTo,
- line->cl_Shell);
- line->cl_MailPos = lseek(mailFd, 0, SEEK_CUR);
+ 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 "cannot create mail file %s for user %s, "
+ crondlog(ERR20 "can't create mail file %s for user %s, "
"discarding output", mailFile, user);
}
}
- ForkJob(user, line, mailFd, DEFAULT_SHELL, "-c", line->cl_Shell, 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);
+ }
+ }
}
/*
- * EndJob - called when job terminates and when mail terminates
+ * process_finished_job - called when job terminates and when mail terminates
*/
-static void EndJob(const char *user, CronLine *line)
+static void process_finished_job(const char *user, CronLine *line)
{
+ pid_t pid;
int mailFd;
char mailFile[128];
struct stat sbuf;
- /* No job */
- if (line->cl_Pid <= 0) {
- line->cl_Pid = 0;
+ pid = line->cl_pid;
+ line->cl_pid = 0;
+ if (pid <= 0) {
+ /* No job */
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) {
+ if (line->cl_empty_mail_size <= 0) {
+ /* End of job and no mail file, or end of sendmail job */
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.
+ * 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 != DaemonUid
- || sbuf.st_nlink != 0 || sbuf.st_size == line->cl_MailPos
+ 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;
}
- if (line->cl_MailTo)
- ForkJob(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 /* crond without sendmail */
+#else /* !ENABLE_FEATURE_CROND_CALL_SENDMAIL */
-static void RunJob(const char *user, CronLine *line)
+static void start_one_job(const char *user, CronLine *line)
{
struct passwd *pas;
pid_t pid;
- /* prepare things before vfork */
pas = getpwnam(user);
if (!pas) {
- crondlog(LVL9 "can't get uid for %s", user);
+ crondlog(WARN9 "can't get uid for %s", user);
goto err;
}
- SetEnv(pas);
- /* fork as the user in question and run program */
+ /* Prepare things before vfork */
+ set_env_vars(pas);
+
+ /* Fork as the user in question and run program */
pid = vfork();
if (pid == 0) {
/* CHILD */
- /* change running state to the user in question */
- ChangeUser(pas);
+ /* initgroups, setgid, setuid, and chdir to home or TMPDIR */
+ change_user(pas);
if (DebugOpt) {
crondlog(LVL5 "child running %s", DEFAULT_SHELL);
}
- execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", line->cl_Shell, NULL);
- crondlog(ERR20 "can't exec, user %s cmd %s %s %s", user,
- DEFAULT_SHELL, "-c", line->cl_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) {
err:
pid = 0;
}
- line->cl_Pid = pid;
+ line->cl_pid = pid;
}
-#endif /* ENABLE_FEATURE_CROND_CALL_SENDMAIL */
+#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 and -d have numeric param */
+ ":l+" IF_FEATURE_CROND_D(":d+");
+ 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(CONFIG_PID_FILE_PATH "/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 */
+}