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45963c873

Denys Vlasenko

2010-07-08

FAILED Duration: 50s

Subject

crond: rename HumpBack names. Note two TODOs/FIXMEs

Binary

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Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

miscutils/crond.c +322 -311

miscutils/crond.c+322 -311

@@ -40,33 +40,33 @@


	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 */
-	char cl_MailTo; / whom to mail results */
-	smallint cl_MailFlag; /* running pid is for mail */
+	int cl_empty_mail_size; /* size of mail header only */
+	char cl_mailto; / whom to mail results, may be NULL */
+	smallint cl_mail_result; /* mail file is created, need to send it on completion */
	#endif
	/* ordered by size, not in natural order. makes code smaller: */
-	char cl_Dow[7]; /* 0-6, beginning sunday */
-	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 {
@@ -79,18 +79,18 @@ enum {
	OPT_d = (1 << 6) * ENABLE_FEATURE_CROND_D,
	};
	#if ENABLE_FEATURE_CROND_D
-	#define DebugOpt (option_mask32 & OPT_d)
+	# define DebugOpt (option_mask32 & OPT_d)
	#else
-	#define DebugOpt 0
+	# define DebugOpt 0
	#endif


	struct globals {
-	unsigned LogLevel; /* = 8; */
-	time_t CDir_mtime;
-	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;
@@ -98,8 +98,8 @@ struct globals {
	} FIX_ALIASING;
	#define G ((struct globals)&bb_common_bufsiz1)
	#define INIT_G() do { \
-	G.LogLevel = 8; \
-	G.CDir = CRONTABS; \
+	G.log_level = 8; \
+	G.crontab_dir_name = CRONTABS; \
	} while (0)


@@ -119,12 +119,12 @@ static void crondlog(const char *ctl, ...)
	int level = (ctl[0] & 0x1f);

	va_start(va, ctl);
-	if (level >= (int)G.LogLevel) {
+	if (level >= (int)G.log_level) {
	/* Debug mode: all to (non-redirected) stderr, */
	/* Syslog mode: all to syslog (logmode = LOGMODE_SYSLOG), */
-	if (!DebugOpt && G.LogFile) {
+	if (!DebugOpt && G.log_filename) {
	/* Otherwise (log to file): we reopen log file at every write: */
-	int logfd = open3_or_warn(G.LogFile, O_WRONLY \| O_CREAT \| O_APPEND, 0666);
+	int logfd = open3_or_warn(G.log_filename, O_WRONLY \| O_CREAT \| O_APPEND, 0666);
	if (logfd >= 0)
	xmove_fd(logfd, STDERR_FILENO);
	}
@@ -144,49 +144,6 @@ static void crondlog(const char *ctl, ...)
	exit(20);
	}

-	#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)
-	{
-	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 SetEnv(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 ChangeUser(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 */
-	}
-	}
-	}
-
	static const char DowAry[] ALIGN1 =
	"sun""mon""tue""wed""thu""fri""sat"
	/* "Sun""Mon""Tue""Wed""Thu""Fri""Sat" */
@@ -303,7 +260,7 @@ static void ParseField(char user, char ary, int modvalue, int off,
	return;
	}

-	if (DebugOpt && (G.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)
@@ -339,48 +296,57 @@ static void FixDayDow(CronLine *line)
	}

	/*
-	* DeleteFile() - delete user database
+	* 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.
	*/
-	static void DeleteFile(const char *userName)
+	//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.
+	static void delete_cronfile(const char *userName)
	{
-	CronFile **pfile = &G.FileBase;
+	CronFile **pfile = &G.cron_files;
	CronFile *file;

	while ((file = *pfile) != NULL) {
-	if (strcmp(userName, file->cf_User) == 0) {
-	CronLine **pline = &file->cf_LineBase;
+	if (strcmp(userName, file->cf_username) == 0) {
+	CronLine **pline = &file->cf_lines;
	CronLine *line;

-	file->cf_Running = 0;
-	file->cf_Deleted = 1;
+	file->cf_has_running = 0;
+	file->cf_deleted = 1;

	while ((line = *pline) != NULL) {
-	if (line->cl_Pid > 0) {
-	file->cf_Running = 1;
-	pline = &line->cl_Next;
+	if (line->cl_pid > 0) {
+	file->cf_has_running = 1;
+	pline = &line->cl_next;
	} else {
-	*pline = line->cl_Next;
-	free(line->cl_Shell);
+	*pline = line->cl_next;
+	free(line->cl_cmd);
	free(line);
	}
	}
-	if (file->cf_Running == 0) {
-	*pfile = file->cf_Next;
-	free(file->cf_User);
+	if (file->cf_has_running == 0) {
+	*pfile = file->cf_next;
+	free(file->cf_username);
	free(file);
-	} else {
-	pfile = &file->cf_Next;
+	continue;
	}
-	} else {
-	pfile = &file->cf_Next;
	}
+	pfile = &file->cf_next;
	}
	}

-	static void SynchronizeFile(const char *fileName)
+	static void load_crontab(const char *fileName)
	{
	struct parser_t *parser;
	struct stat sbuf;
@@ -390,23 +356,26 @@ static void SynchronizeFile(const char *fileName)
	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 (1) {
	CronLine *line;
@@ -433,11 +402,11 @@ static void SynchronizeFile(const char *fileName)
	continue;
	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
@@ -445,20 +414,20 @@ static void SynchronizeFile(const char *fileName)
	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 = G.FileBase;
-	G.FileBase = file;
+	file->cf_next = G.cron_files;
+	G.cron_files = file;

	if (maxLines == 0) {
	crondlog(WARN9 "user %s: too many lines", fileName);
@@ -467,7 +436,7 @@ static void SynchronizeFile(const char *fileName)
	config_close(parser);
	}

-	static void CheckUpdates(void)
+	static void process_cron_update_file(void)
	{
	FILE *fi;
	char buf[256];
@@ -477,36 +446,34 @@ static void CheckUpdates(void)
	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 = G.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(G.CDir) < 0) {
-	crondlog(DIE9 "chdir(%s)", G.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;
@@ -517,162 +484,62 @@ static void SynchronizeDir(void)
	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);
	}
	}

-	/*
-	* 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 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)
	{
-	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;
+	char var_val = pvar_val;

-	ptm = localtime(&t);
-	for (file = G.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[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_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;
-	}
-	}
-	}
-	}
+	if (var_val) {
+	bb_unsetenv_and_free(var_val);
	}
+	*pvar_val = xasprintf("%s=%s", var, val);
+	putenv(*pvar_val);
	}
+	#endif

-	#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)
+	static void set_env_vars(struct passwd *pas)
	{
-	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);
-	}
+	#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
-	# define EndJob(user, line) ((line)->cl_Pid = 0)
+	xsetenv("USER", pas->pw_name);
+	xsetenv("HOME", pas->pw_dir);
	#endif
+	/* currently, we use constant one: */
+	/setenv("SHELL", DEFAULT_SHELL, 1); - done earlier /
+	}

-	/*
-	* 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 = G.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

+	//TODO: return pid (and stop passing line);
+	// stop passing mail_filename here but process it in caller
	static void
-	ForkJob(const char user, CronLine line, int mailFd,
+	fork_job(const char user, CronLine line, int mailFd,
	const char prog, const char cmd, const char *arg,
	const char *mail_filename)
	{
@@ -685,13 +552,13 @@ ForkJob(const char user, CronLine line, int mailFd,
	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);
	}
@@ -709,12 +576,12 @@ ForkJob(const char user, CronLine line, int mailFd,
	_exit(EXIT_SUCCESS);
	}

-	line->cl_Pid = pid;
+	line->cl_pid = pid;
	if (pid < 0) {
	/* FORK FAILED */
	crondlog(ERR20 "can't vfork");
	err:
-	line->cl_Pid = 0;
+	line->cl_pid = 0;
	if (mail_filename) {
	unlink(mail_filename);
	}
@@ -737,62 +604,108 @@ ForkJob(const char user, CronLine line, int mailFd,
	}
	}

-	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_mail_result = 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);
+	line->cl_mail_result = 1;
+	fdprintf(mailFd, "To: %s\nSubject: cron: %s\n\n", line->cl_mailto,
+	line->cl_cmd);
+	line->cl_empty_mail_size = lseek(mailFd, 0, SEEK_CUR);
	} else {
	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);
+	fork_job(user, line, mailFd, DEFAULT_SHELL, "-c", line->cl_cmd, mailFile);
+	}
+
+	/*
+	* 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_mail_result == 0) {
+	/* End of job and no mail file, or end of sendmail job */
+	return;
+	}
+	line->cl_mail_result = 0;
+
+	/*
+	* End of primary job - check for mail file.
+	* 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;
+	}
+	/* if (line->cl_mailto) - always true if cl_mail_result was true */
+	fork_job(user, line, mailFd, SENDMAIL, SENDMAIL_ARGS, NULL);
	}

	#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(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);
	}
	/* crond 3.0pl1-100 puts tasks in separate process groups */
	bb_setpgrp();
-	execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", line->cl_Shell, (char *) NULL);
-	crondlog(ERR20 "can't exec, user %s cmd %s %s %s", user,
-	DEFAULT_SHELL, "-c", line->cl_Shell);
+	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) {
@@ -801,35 +714,130 @@ static void RunJob(const char user, CronLine line)
	err:
	pid = 0;
	}
-	line->cl_Pid = pid;
+	line->cl_pid = pid;
	}

+	#define process_finished_job(user, line) ((line)->cl_pid = 0)
+
	#endif /* !ENABLE_FEATURE_CROND_CALL_SENDMAIL */

-	static void RunJobs(void)
+	/*
+	* 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.FileBase; file; file = file->cf_Next) {
-	if (!file->cf_Ready)
+	for (file = G.cron_files; file; file = file->cf_next) {
+	if (!file->cf_wants_starting)
	continue;

-	file->cf_Ready = 0;
-	for (line = file->cf_LineBase; line; line = line->cl_Next) {
-	if (line->cl_Pid >= 0)
+	file->cf_wants_starting = 0;
+	for (line = file->cf_lines; line; line = line->cl_next) {
+	pid_t pid;
+	if (line->cl_pid >= 0)
	continue;

-	RunJob(file->cf_User, line);
+	start_one_job(file->cf_username, line);
+	pid = line->cl_pid;
	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;
+	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;
@@ -846,9 +854,9 @@ int crond_main(int argc UNUSED_PARAM, char **argv)
	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.LogLevel, &G.LogFile, &G.CDir
-	IF_FEATURE_CROND_D(,&G.LogLevel));
-	/* both -d N and -l N set the same variable: G.LogLevel */
+	&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.
@@ -856,17 +864,17 @@ int crond_main(int argc UNUSED_PARAM, char **argv)
	bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
	}

-	if (!(opts & OPT_d) && G.LogFile == NULL) {
+	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.CDir);
+	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.LogLevel);
-	SynchronizeDir();
+	crondlog(LVL8 "crond (busybox "BB_VER") started, log level %d", G.log_level);
+	rescan_crontab_dir();
	write_pidfile("/var/run/crond.pid");

	/* Main loop */
@@ -902,15 +910,17 @@ int crond_main(int argc UNUSED_PARAM, char **argv)
	* When running jobs, the inequality used is greater but not
	* equal to t1, and less then or equal to t2.
	*/
-	if (stat(G.CDir, &sbuf) == 0 && G.CDir_mtime != sbuf.st_mtime) {
-	G.CDir_mtime = sbuf.st_mtime;
+	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;
-	SynchronizeDir();
+	rescan_crontab_dir();
	}
-	CheckUpdates();
+	process_cron_update_file();
	if (DebugOpt)
	crondlog(LVL5 "wakeup dt=%ld", dt);
	if (dt < -60 * 60 \|\| dt > 60 * 60) {
@@ -918,9 +928,10 @@ int crond_main(int argc UNUSED_PARAM, char **argv)
	/* and we do not run any jobs in this case */
	} else if (dt > 0) {
	/* Usual case: time advances forward, as expected */
-	TestJobs(t1, t2);
-	RunJobs();
-	if (CheckJobs() > 0) {
+	flag_starting_jobs(t1, t2);
+	start_jobs();
+	if (check_completions() > 0) {
+	/* some jobs are still running */
	sleep_time = 10;
	} else {
	sleep_time = 60;