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crond: rename HumpBack names. Note two TODOs/FIXMEs

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Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2010-07-08 15:37:10 +02:00
parent dfc870fab7
commit 45963c873c
1 changed files with 327 additions and 316 deletions
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643
miscutils/crond.c
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@ -40,33 +40,33 @@
typedef struct CronFile { typedef struct CronFile {
struct CronFile *cf_Next; struct CronFile *cf_next;
struct CronLine *cf_LineBase; struct CronLine *cf_lines;
char *cf_User; /* username */ char *cf_username;
smallint cf_Ready; /* bool: one or more jobs ready */ smallint cf_wants_starting; /* bool: one or more jobs ready */
smallint cf_Running; /* bool: one or more jobs running */ smallint cf_has_running; /* bool: one or more jobs running */
smallint cf_Deleted; /* marked for deletion, ignore */ smallint cf_deleted; /* marked for deletion (but still has running jobs) */
} CronFile; } CronFile;
typedef struct CronLine { typedef struct CronLine {
struct CronLine *cl_Next; struct CronLine *cl_next;
char *cl_Shell; /* shell command */ char *cl_cmd; /* shell command */
pid_t cl_Pid; /* running pid, 0, or armed (-1) */ pid_t cl_pid; /* >0:running, <0:needs to be started in this minute, 0:dormant */
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL #if ENABLE_FEATURE_CROND_CALL_SENDMAIL
int cl_MailPos; /* 'empty file' size */ int cl_empty_mail_size; /* size of mail header only */
char *cl_MailTo; /* whom to mail results */ char *cl_mailto; /* whom to mail results, may be NULL */
smallint cl_MailFlag; /* running pid is for mail */ smallint cl_mail_result; /* mail file is created, need to send it on completion */
#endif #endif
/* ordered by size, not in natural order. makes code smaller: */ /* ordered by size, not in natural order. makes code smaller: */
char cl_Dow[7]; /* 0-6, beginning sunday */ char cl_Dow[7]; /* 0-6, beginning sunday */
char cl_Mons[12]; /* 0-11 */ char cl_Mons[12]; /* 0-11 */
char cl_Hrs[24]; /* 0-23 */ char cl_Hrs[24]; /* 0-23 */
char cl_Days[32]; /* 1-31 */ char cl_Days[32]; /* 1-31 */
char cl_Mins[60]; /* 0-59 */ char cl_Mins[60]; /* 0-59 */
} CronLine; } CronLine;
#define DaemonUid 0 #define DAEMON_UID 0
enum { enum {
@ -79,18 +79,18 @@ enum {
OPT_d = (1 << 6) * ENABLE_FEATURE_CROND_D, OPT_d = (1 << 6) * ENABLE_FEATURE_CROND_D,
}; };
#if ENABLE_FEATURE_CROND_D #if ENABLE_FEATURE_CROND_D
#define DebugOpt (option_mask32 & OPT_d) # define DebugOpt (option_mask32 & OPT_d)
#else #else
#define DebugOpt 0 # define DebugOpt 0
#endif #endif
struct globals { struct globals {
unsigned LogLevel; /* = 8; */ unsigned log_level; /* = 8; */
time_t CDir_mtime; time_t crontab_dir_mtime;
const char *LogFile; const char *log_filename;
const char *CDir; /* = CRONTABS; */ const char *crontab_dir_name; /* = CRONTABS; */
CronFile *FileBase; CronFile *cron_files;
#if SETENV_LEAKS #if SETENV_LEAKS
char *env_var_user; char *env_var_user;
char *env_var_home; char *env_var_home;
@ -98,8 +98,8 @@ struct globals {
} FIX_ALIASING; } FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1) #define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { \ #define INIT_G() do { \
G.LogLevel = 8; \ G.log_level = 8; \
G.CDir = CRONTABS; \ G.crontab_dir_name = CRONTABS; \
} while (0) } while (0)
@ -119,12 +119,12 @@ static void crondlog(const char *ctl, ...)
int level = (ctl[0] & 0x1f); int level = (ctl[0] & 0x1f);
va_start(va, ctl); va_start(va, ctl);
if (level >= (int)G.LogLevel) { if (level >= (int)G.log_level) {
/* Debug mode: all to (non-redirected) stderr, */ /* Debug mode: all to (non-redirected) stderr, */
/* Syslog mode: all to syslog (logmode = LOGMODE_SYSLOG), */ /* 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: */ /* 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) if (logfd >= 0)
xmove_fd(logfd, STDERR_FILENO); xmove_fd(logfd, STDERR_FILENO);
} }
@ -144,49 +144,6 @@ static void crondlog(const char *ctl, ...)
exit(20); 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 = static const char DowAry[] ALIGN1 =
"sun""mon""tue""wed""thu""fri""sat" "sun""mon""tue""wed""thu""fri""sat"
/* "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; return;
} }
if (DebugOpt && (G.LogLevel <= 5)) { /* like LVL5 */ if (DebugOpt && (G.log_level <= 5)) { /* like LVL5 */
/* can't use crondlog, it inserts '\n' */ /* can't use crondlog, it inserts '\n' */
int i; int i;
for (i = 0; i < modvalue; ++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 * Note: multiple entries for same user may exist if we were unable to
* completely delete a database due to running processes. * 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; CronFile *file;
while ((file = *pfile) != NULL) { while ((file = *pfile) != NULL) {
if (strcmp(userName, file->cf_User) == 0) { if (strcmp(userName, file->cf_username) == 0) {
CronLine **pline = &file->cf_LineBase; CronLine **pline = &file->cf_lines;
CronLine *line; CronLine *line;
file->cf_Running = 0; file->cf_has_running = 0;
file->cf_Deleted = 1; file->cf_deleted = 1;
while ((line = *pline) != NULL) { while ((line = *pline) != NULL) {
if (line->cl_Pid > 0) { if (line->cl_pid > 0) {
file->cf_Running = 1; file->cf_has_running = 1;
pline = &line->cl_Next; pline = &line->cl_next;
} else { } else {
*pline = line->cl_Next; *pline = line->cl_next;
free(line->cl_Shell); free(line->cl_cmd);
free(line); free(line);
} }
} }
if (file->cf_Running == 0) { if (file->cf_has_running == 0) {
*pfile = file->cf_Next; *pfile = file->cf_next;
free(file->cf_User); free(file->cf_username);
free(file); free(file);
} else { continue;
pfile = &file->cf_Next;
} }
} 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 parser_t *parser;
struct stat sbuf; struct stat sbuf;
@ -390,23 +356,26 @@ static void SynchronizeFile(const char *fileName)
char *mailTo = NULL; char *mailTo = NULL;
#endif #endif
if (!fileName) delete_cronfile(fileName);
return;
if (!getpwnam(fileName)) {
crondlog(LVL7 "ignoring file '%s' (no such user)", fileName);
return;
}
DeleteFile(fileName);
parser = config_open(fileName); parser = config_open(fileName);
if (!parser) if (!parser)
return; return;
maxLines = (strcmp(fileName, "root") == 0) ? 65535 : MAXLINES; 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)); CronFile *file = xzalloc(sizeof(CronFile));
CronLine **pline; CronLine **pline;
int n; int n;
file->cf_User = xstrdup(fileName); file->cf_username = xstrdup(fileName);
pline = &file->cf_LineBase; pline = &file->cf_lines;
while (1) { while (1) {
CronLine *line; CronLine *line;
@ -433,11 +402,11 @@ static void SynchronizeFile(const char *fileName)
continue; continue;
*pline = line = xzalloc(sizeof(*line)); *pline = line = xzalloc(sizeof(*line));
/* parse date ranges */ /* parse date ranges */
ParseField(file->cf_User, line->cl_Mins, 60, 0, NULL, tokens[0]); ParseField(file->cf_username, line->cl_Mins, 60, 0, NULL, tokens[0]);
ParseField(file->cf_User, line->cl_Hrs, 24, 0, NULL, tokens[1]); ParseField(file->cf_username, line->cl_Hrs, 24, 0, NULL, tokens[1]);
ParseField(file->cf_User, line->cl_Days, 32, 0, NULL, tokens[2]); ParseField(file->cf_username, line->cl_Days, 32, 0, NULL, tokens[2]);
ParseField(file->cf_User, line->cl_Mons, 12, -1, MonAry, tokens[3]); ParseField(file->cf_username, 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_Dow, 7, 0, DowAry, tokens[4]);
/* /*
* fix days and dow - if one is not "*" and the other * fix days and dow - if one is not "*" and the other
* is "*", the other is set to 0, and vise-versa * is "*", the other is set to 0, and vise-versa
@ -445,20 +414,20 @@ static void SynchronizeFile(const char *fileName)
FixDayDow(line); FixDayDow(line);
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL #if ENABLE_FEATURE_CROND_CALL_SENDMAIL
/* copy mailto (can be NULL) */ /* copy mailto (can be NULL) */
line->cl_MailTo = xstrdup(mailTo); line->cl_mailto = xstrdup(mailTo);
#endif #endif
/* copy command */ /* copy command */
line->cl_Shell = xstrdup(tokens[5]); line->cl_cmd = xstrdup(tokens[5]);
if (DebugOpt) { if (DebugOpt) {
crondlog(LVL5 " command:%s", tokens[5]); 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]); //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; *pline = NULL;
file->cf_Next = G.FileBase; file->cf_next = G.cron_files;
G.FileBase = file; G.cron_files = file;
if (maxLines == 0) { if (maxLines == 0) {
crondlog(WARN9 "user %s: too many lines", fileName); crondlog(WARN9 "user %s: too many lines", fileName);
@ -467,7 +436,7 @@ static void SynchronizeFile(const char *fileName)
config_close(parser); config_close(parser);
} }
static void CheckUpdates(void) static void process_cron_update_file(void)
{ {
FILE *fi; FILE *fi;
char buf[256]; char buf[256];
@ -477,36 +446,34 @@ static void CheckUpdates(void)
unlink(CRONUPDATE); unlink(CRONUPDATE);
while (fgets(buf, sizeof(buf), fi) != NULL) { while (fgets(buf, sizeof(buf), fi) != NULL) {
/* use first word only */ /* use first word only */
SynchronizeFile(strtok(buf, " \t\r\n")); skip_non_whitespace(buf)[0] = '\0';
load_crontab(buf);
} }
fclose(fi); fclose(fi);
} }
} }
static void SynchronizeDir(void) static void rescan_crontab_dir(void)
{ {
CronFile *file; CronFile *file;
/* Attempt to delete the database. */
/* Delete all files until we only have ones with running jobs (or none) */
again: again:
for (file = G.FileBase; file; file = file->cf_Next) { for (file = G.cron_files; file; file = file->cf_next) {
if (!file->cf_Deleted) { if (!file->cf_deleted) {
DeleteFile(file->cf_User); delete_cronfile(file->cf_username);
goto again; goto again;
} }
} }
/* /* Remove cron update file */
* Remove cron update file
*
* Re-chdir, in case directory was renamed & deleted, or otherwise
* screwed up.
*
* scan directory and add associated users
*/
unlink(CRONUPDATE); unlink(CRONUPDATE);
if (chdir(G.CDir) < 0) { /* Re-chdir, in case directory was renamed & deleted */
crondlog(DIE9 "chdir(%s)", G.CDir); if (chdir(G.crontab_dir_name) < 0) {
crondlog(DIE9 "chdir(%s)", G.crontab_dir_name);
} }
/* Scan directory and add associated users */
{ {
DIR *dir = opendir("."); DIR *dir = opendir(".");
struct dirent *den; struct dirent *den;
@ -517,162 +484,62 @@ static void SynchronizeDir(void)
if (strchr(den->d_name, '.') != NULL) { if (strchr(den->d_name, '.') != NULL) {
continue; continue;
} }
if (getpwnam(den->d_name)) { load_crontab(den->d_name);
SynchronizeFile(den->d_name);
} else {
crondlog(LVL7 "ignoring %s", den->d_name);
}
} }
closedir(dir); closedir(dir);
} }
} }
/* #if SETENV_LEAKS
* Determine which jobs need to be run. Under normal conditions, the /* We set environment *before* vfork (because we want to use vfork),
* period is about a minute (one scan). Worst case it will be one * so we cannot use setenv() - repeated calls to setenv() may leak memory!
* hour (60 scans). * Using putenv(), and freeing memory after unsetenv() won't leak */
*/ static void safe_setenv(char **pvar_val, const char *var, const char *val)
static void TestJobs(time_t t1, time_t t2)
{ {
time_t t; char *var_val = *pvar_val;
/* Find jobs > t1 and <= t2 */ if (var_val) {
bb_unsetenv_and_free(var_val);
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.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;
}
}
}
}
} }
*pvar_val = xasprintf("%s=%s", var, val);
putenv(*pvar_val);
} }
#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)
{
int mailFd;
char mailFile[128];
struct stat sbuf;
/* No job */
if (line->cl_Pid <= 0) {
line->cl_Pid = 0;
return;
}
/*
* End of job and no mail file
* End of sendmail job
*/
snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, line->cl_Pid);
line->cl_Pid = 0;
if (line->cl_MailFlag == 0) {
return;
}
line->cl_MailFlag = 0;
/*
* End of primary job - check for mail file. If size has increased and
* the file is still valid, we sendmail it.
*/
mailFd = open(mailFile, O_RDONLY);
unlink(mailFile);
if (mailFd < 0) {
return;
}
if (fstat(mailFd, &sbuf) < 0 || sbuf.st_uid != DaemonUid
|| sbuf.st_nlink != 0 || sbuf.st_size == line->cl_MailPos
|| !S_ISREG(sbuf.st_mode)
) {
close(mailFd);
return;
}
if (line->cl_MailTo)
ForkJob(user, line, mailFd, SENDMAIL, SENDMAIL_ARGS, NULL);
}
#else
# define EndJob(user, line) ((line)->cl_Pid = 0)
#endif #endif
/* static void set_env_vars(struct passwd *pas)
* Check for job completion, return number of jobs still running after
* all done.
*/
static int CheckJobs(void)
{ {
CronFile *file; #if SETENV_LEAKS
CronLine *line; safe_setenv(&G.env_var_user, "USER", pas->pw_name);
int nStillRunning = 0; safe_setenv(&G.env_var_home, "HOME", pas->pw_dir);
/* if we want to set user's shell instead: */
for (file = G.FileBase; file; file = file->cf_Next) { /*safe_setenv(G.env_var_shell, "SHELL", pas->pw_shell);*/
if (file->cf_Running) { #else
file->cf_Running = 0; xsetenv("USER", pas->pw_name);
xsetenv("HOME", pas->pw_dir);
for (line = file->cf_LineBase; line; line = line->cl_Next) { #endif
int status, r; /* currently, we use constant one: */
if (line->cl_Pid <= 0) /*setenv("SHELL", DEFAULT_SHELL, 1); - done earlier */
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;
}
}
}
nStillRunning += file->cf_Running;
}
return nStillRunning;
} }
#if ENABLE_FEATURE_CROND_CALL_SENDMAIL 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! // 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 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 *prog, const char *cmd, const char *arg,
const char *mail_filename) 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); crondlog(WARN9 "can't get uid for %s", user);
goto err; goto err;
} }
SetEnv(pas); set_env_vars(pas);
pid = vfork(); pid = vfork();
if (pid == 0) { if (pid == 0) {
/* CHILD */ /* CHILD */
/* change running state to the user in question */ /* initgroups, setgid, setuid, and chdir to home or TMPDIR */
ChangeUser(pas); change_user(pas);
if (DebugOpt) { if (DebugOpt) {
crondlog(LVL5 "child running %s", prog); crondlog(LVL5 "child running %s", prog);
} }
@ -709,12 +576,12 @@ ForkJob(const char *user, CronLine *line, int mailFd,
_exit(EXIT_SUCCESS); _exit(EXIT_SUCCESS);
} }
line->cl_Pid = pid; line->cl_pid = pid;
if (pid < 0) { if (pid < 0) {
/* FORK FAILED */ /* FORK FAILED */
crondlog(ERR20 "can't vfork"); crondlog(ERR20 "can't vfork");
err: err:
line->cl_Pid = 0; line->cl_pid = 0;
if (mail_filename) { if (mail_filename) {
unlink(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]; char mailFile[128];
int mailFd = -1; int mailFd = -1;
line->cl_Pid = 0; line->cl_pid = 0;
line->cl_MailFlag = 0; line->cl_mail_result = 0;
if (line->cl_MailTo) { if (line->cl_mailto) {
/* open mail file - owner root so nobody can screw with it. */ /* Open mail file (owner is root so nobody can screw with it) */
snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, getpid()); 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); mailFd = open(mailFile, O_CREAT | O_TRUNC | O_WRONLY | O_EXCL | O_APPEND, 0600);
if (mailFd >= 0) { if (mailFd >= 0) {
line->cl_MailFlag = 1; line->cl_mail_result = 1;
fdprintf(mailFd, "To: %s\nSubject: cron: %s\n\n", line->cl_MailTo, fdprintf(mailFd, "To: %s\nSubject: cron: %s\n\n", line->cl_mailto,
line->cl_Shell); line->cl_cmd);
line->cl_MailPos = lseek(mailFd, 0, SEEK_CUR); line->cl_empty_mail_size = lseek(mailFd, 0, SEEK_CUR);
} else { } else {
crondlog(ERR20 "can't create mail file %s for user %s, " crondlog(ERR20 "can't create mail file %s for user %s, "
"discarding output", mailFile, user); "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 */ #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; struct passwd *pas;
pid_t pid; pid_t pid;
/* prepare things before vfork */
pas = getpwnam(user); pas = getpwnam(user);
if (!pas) { if (!pas) {
crondlog(WARN9 "can't get uid for %s", user); crondlog(WARN9 "can't get uid for %s", user);
goto err; 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(); pid = vfork();
if (pid == 0) { if (pid == 0) {
/* CHILD */ /* CHILD */
/* change running state to the user in question */ /* initgroups, setgid, setuid, and chdir to home or TMPDIR */
ChangeUser(pas); change_user(pas);
if (DebugOpt) { if (DebugOpt) {
crondlog(LVL5 "child running %s", DEFAULT_SHELL); crondlog(LVL5 "child running %s", DEFAULT_SHELL);
} }
/* crond 3.0pl1-100 puts tasks in separate process groups */ /* crond 3.0pl1-100 puts tasks in separate process groups */
bb_setpgrp(); bb_setpgrp();
execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", line->cl_Shell, (char *) NULL); execl(DEFAULT_SHELL, DEFAULT_SHELL, "-c", line->cl_cmd, (char *) NULL);
crondlog(ERR20 "can't exec, user %s cmd %s %s %s", user, crondlog(ERR20 "can't execute '%s' for user %s", DEFAULT_SHELL, user);
DEFAULT_SHELL, "-c", line->cl_Shell);
_exit(EXIT_SUCCESS); _exit(EXIT_SUCCESS);
} }
if (pid < 0) { if (pid < 0) {
@ -801,37 +714,132 @@ static void RunJob(const char *user, CronLine *line)
err: err:
pid = 0; 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 */ #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; CronFile *file;
CronLine *line; CronLine *line;
for (file = G.FileBase; file; file = file->cf_Next) { for (file = G.cron_files; file; file = file->cf_next) {
if (!file->cf_Ready) if (!file->cf_wants_starting)
continue; continue;
file->cf_Ready = 0; file->cf_wants_starting = 0;
for (line = file->cf_LineBase; line; line = line->cl_Next) { for (line = file->cf_lines; line; line = line->cl_next) {
if (line->cl_Pid >= 0) pid_t pid;
if (line->cl_pid >= 0)
continue; 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", crondlog(LVL8 "USER %s pid %3d cmd %s",
file->cf_User, (int)line->cl_Pid, line->cl_Shell); file->cf_username, (int)pid, line->cl_cmd);
if (line->cl_Pid < 0) { if (pid < 0) {
file->cf_Ready = 1; file->cf_wants_starting = 1;
} else if (line->cl_Pid > 0) { }
file->cf_Running = 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, char **argv) MAIN_EXTERNALLY_VISIBLE;
int crond_main(int argc UNUSED_PARAM, char **argv) int crond_main(int argc UNUSED_PARAM, char **argv)
{ {
@ -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") opt_complementary = "f-b:b-f:S-L:L-S" IF_FEATURE_CROND_D(":d-l")
":l+:d+"; /* -l and -d have numeric param */ ":l+:d+"; /* -l and -d have numeric param */
opts = getopt32(argv, "l:L:fbSc:" IF_FEATURE_CROND_D("d:"), opts = getopt32(argv, "l:L:fbSc:" IF_FEATURE_CROND_D("d:"),
&G.LogLevel, &G.LogFile, &G.CDir &G.log_level, &G.log_filename, &G.crontab_dir_name
IF_FEATURE_CROND_D(,&G.LogLevel)); IF_FEATURE_CROND_D(,&G.log_level));
/* both -d N and -l N set the same variable: G.LogLevel */ /* both -d N and -l N set the same variable: G.log_level */
if (!(opts & OPT_f)) { if (!(opts & OPT_f)) {
/* close stdin, stdout, stderr. /* 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); 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 */ /* logging to syslog */
openlog(applet_name, LOG_CONS | LOG_PID, LOG_CRON); openlog(applet_name, LOG_CONS | LOG_PID, LOG_CRON);
logmode = LOGMODE_SYSLOG; logmode = LOGMODE_SYSLOG;
} }
xchdir(G.CDir); xchdir(G.crontab_dir_name);
//signal(SIGHUP, SIG_IGN); /* ? original crond dies on HUP... */ //signal(SIGHUP, SIG_IGN); /* ? original crond dies on HUP... */
xsetenv("SHELL", DEFAULT_SHELL); /* once, for all future children */ xsetenv("SHELL", DEFAULT_SHELL); /* once, for all future children */
crondlog(LVL8 "crond (busybox "BB_VER") started, log level %d", G.LogLevel); crondlog(LVL8 "crond (busybox "BB_VER") started, log level %d", G.log_level);
SynchronizeDir(); rescan_crontab_dir();
write_pidfile("/var/run/crond.pid"); write_pidfile("/var/run/crond.pid");
/* Main loop */ /* 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 * When running jobs, the inequality used is greater but not
* equal to t1, and less then or equal to t2. * equal to t1, and less then or equal to t2.
*/ */
if (stat(G.CDir, &sbuf) == 0 && G.CDir_mtime != sbuf.st_mtime) { if (stat(G.crontab_dir_name, &sbuf) != 0)
G.CDir_mtime = sbuf.st_mtime; 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; rescan = 1;
} }
if (--rescan == 0) { if (--rescan == 0) {
rescan = 60; rescan = 60;
SynchronizeDir(); rescan_crontab_dir();
} }
CheckUpdates(); process_cron_update_file();
if (DebugOpt) if (DebugOpt)
crondlog(LVL5 "wakeup dt=%ld", dt); crondlog(LVL5 "wakeup dt=%ld", dt);
if (dt < -60 * 60 || dt > 60 * 60) { 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 */ /* and we do not run any jobs in this case */
} else if (dt > 0) { } else if (dt > 0) {
/* Usual case: time advances forward, as expected */ /* Usual case: time advances forward, as expected */
TestJobs(t1, t2); flag_starting_jobs(t1, t2);
RunJobs(); start_jobs();
if (CheckJobs() > 0) { if (check_completions() > 0) {
/* some jobs are still running */
sleep_time = 10; sleep_time = 10;
} else { } else {
sleep_time = 60; sleep_time = 60;