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-rw-r--r--util/sbase/cron.c566
1 files changed, 566 insertions, 0 deletions
diff --git a/util/sbase/cron.c b/util/sbase/cron.c
new file mode 100644
index 00000000..77304ccf
--- /dev/null
+++ b/util/sbase/cron.c
@@ -0,0 +1,566 @@
+/* See LICENSE file for copyright and license details. */
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include <errno.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+#include <syslog.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "queue.h"
+#include "util.h"
+
+struct field {
+ enum {
+ ERROR,
+ WILDCARD,
+ NUMBER,
+ RANGE,
+ REPEAT,
+ LIST
+ } type;
+ long *val;
+ int len;
+};
+
+struct ctabentry {
+ struct field min;
+ struct field hour;
+ struct field mday;
+ struct field mon;
+ struct field wday;
+ char *cmd;
+ TAILQ_ENTRY(ctabentry) entry;
+};
+
+struct jobentry {
+ char *cmd;
+ pid_t pid;
+ TAILQ_ENTRY(jobentry) entry;
+};
+
+static sig_atomic_t chldreap;
+static sig_atomic_t reload;
+static sig_atomic_t quit;
+static TAILQ_HEAD(, ctabentry) ctabhead = TAILQ_HEAD_INITIALIZER(ctabhead);
+static TAILQ_HEAD(, jobentry) jobhead = TAILQ_HEAD_INITIALIZER(jobhead);
+static char *config = "/etc/crontab";
+static char *pidfile = "/var/run/crond.pid";
+static int nflag;
+
+static void
+loginfo(const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ if (nflag == 0)
+ vsyslog(LOG_INFO, fmt, ap);
+ else
+ vfprintf(stdout, fmt, ap);
+ fflush(stdout);
+ va_end(ap);
+}
+
+static void
+logwarn(const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ if (nflag == 0)
+ vsyslog(LOG_WARNING, fmt, ap);
+ else
+ vfprintf(stderr, fmt, ap);
+ va_end(ap);
+}
+
+static void
+logerr(const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ if (nflag == 0)
+ vsyslog(LOG_ERR, fmt, ap);
+ else
+ vfprintf(stderr, fmt, ap);
+ va_end(ap);
+}
+
+static void
+runjob(char *cmd)
+{
+ struct jobentry *je;
+ time_t t;
+ pid_t pid;
+
+ t = time(NULL);
+
+ /* If command is already running, skip it */
+ TAILQ_FOREACH(je, &jobhead, entry) {
+ if (strcmp(je->cmd, cmd) == 0) {
+ loginfo("already running %s pid: %d at %s",
+ je->cmd, je->pid, ctime(&t));
+ return;
+ }
+ }
+
+ switch ((pid = fork())) {
+ case -1:
+ logerr("error: failed to fork job: %s time: %s",
+ cmd, ctime(&t));
+ return;
+ case 0:
+ setsid();
+ loginfo("run: %s pid: %d at %s",
+ cmd, getpid(), ctime(&t));
+ execl("/bin/sh", "/bin/sh", "-c", cmd, (char *)NULL);
+ logerr("error: failed to execute job: %s time: %s",
+ cmd, ctime(&t));
+ _exit(1);
+ default:
+ je = emalloc(sizeof(*je));
+ je->cmd = estrdup(cmd);
+ je->pid = pid;
+ TAILQ_INSERT_TAIL(&jobhead, je, entry);
+ }
+}
+
+static void
+waitjob(void)
+{
+ struct jobentry *je, *tmp;
+ int status;
+ time_t t;
+ pid_t pid;
+
+ t = time(NULL);
+
+ while ((pid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) {
+ je = NULL;
+ TAILQ_FOREACH(tmp, &jobhead, entry) {
+ if (tmp->pid == pid) {
+ je = tmp;
+ break;
+ }
+ }
+ if (je) {
+ TAILQ_REMOVE(&jobhead, je, entry);
+ free(je->cmd);
+ free(je);
+ }
+ if (WIFEXITED(status) == 1)
+ loginfo("complete: pid: %d returned: %d time: %s",
+ pid, WEXITSTATUS(status), ctime(&t));
+ else if (WIFSIGNALED(status) == 1)
+ loginfo("complete: pid: %d terminated by signal: %s time: %s",
+ pid, strsignal(WTERMSIG(status)), ctime(&t));
+ else if (WIFSTOPPED(status) == 1)
+ loginfo("complete: pid: %d stopped by signal: %s time: %s",
+ pid, strsignal(WSTOPSIG(status)), ctime(&t));
+ }
+}
+
+static int
+isleap(int year)
+{
+ if (year % 400 == 0)
+ return 1;
+ if (year % 100 == 0)
+ return 0;
+ return (year % 4 == 0);
+}
+
+static int
+daysinmon(int mon, int year)
+{
+ int days[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
+ if (year < 1900)
+ year += 1900;
+ if (isleap(year))
+ days[1] = 29;
+ return days[mon];
+}
+
+static int
+matchentry(struct ctabentry *cte, struct tm *tm)
+{
+ struct {
+ struct field *f;
+ int tm;
+ int len;
+ } matchtbl[] = {
+ { .f = &cte->min, .tm = tm->tm_min, .len = 60 },
+ { .f = &cte->hour, .tm = tm->tm_hour, .len = 24 },
+ { .f = &cte->mday, .tm = tm->tm_mday, .len = daysinmon(tm->tm_mon, tm->tm_year) },
+ { .f = &cte->mon, .tm = tm->tm_mon, .len = 12 },
+ { .f = &cte->wday, .tm = tm->tm_wday, .len = 7 },
+ };
+ size_t i;
+ int j;
+
+ for (i = 0; i < LEN(matchtbl); i++) {
+ switch (matchtbl[i].f->type) {
+ case WILDCARD:
+ continue;
+ case NUMBER:
+ if (matchtbl[i].f->val[0] == matchtbl[i].tm)
+ continue;
+ break;
+ case RANGE:
+ if (matchtbl[i].f->val[0] <= matchtbl[i].tm)
+ if (matchtbl[i].f->val[1] >= matchtbl[i].tm)
+ continue;
+ break;
+ case REPEAT:
+ if (matchtbl[i].tm > 0) {
+ if (matchtbl[i].tm % matchtbl[i].f->val[0] == 0)
+ continue;
+ } else {
+ if (matchtbl[i].len % matchtbl[i].f->val[0] == 0)
+ continue;
+ }
+ break;
+ case LIST:
+ for (j = 0; j < matchtbl[i].f->len; j++)
+ if (matchtbl[i].f->val[j] == matchtbl[i].tm)
+ break;
+ if (j < matchtbl[i].f->len)
+ continue;
+ break;
+ default:
+ break;
+ }
+ break;
+ }
+ if (i != LEN(matchtbl))
+ return 0;
+ return 1;
+}
+
+static int
+parsefield(const char *field, long low, long high, struct field *f)
+{
+ int i;
+ char *e1, *e2;
+ const char *p;
+
+ p = field;
+ while (isdigit(*p))
+ p++;
+
+ f->type = ERROR;
+
+ switch (*p) {
+ case '*':
+ if (strcmp(field, "*") == 0) {
+ f->val = NULL;
+ f->len = 0;
+ f->type = WILDCARD;
+ } else if (strncmp(field, "*/", 2) == 0) {
+ f->val = emalloc(sizeof(*f->val));
+ f->len = 1;
+
+ errno = 0;
+ f->val[0] = strtol(field + 2, &e1, 10);
+ if (e1[0] != '\0' || errno != 0 || f->val[0] == 0)
+ break;
+
+ f->type = REPEAT;
+ }
+ break;
+ case '\0':
+ f->val = emalloc(sizeof(*f->val));
+ f->len = 1;
+
+ errno = 0;
+ f->val[0] = strtol(field, &e1, 10);
+ if (e1[0] != '\0' || errno != 0)
+ break;
+
+ f->type = NUMBER;
+ break;
+ case '-':
+ f->val = emalloc(2 * sizeof(*f->val));
+ f->len = 2;
+
+ errno = 0;
+ f->val[0] = strtol(field, &e1, 10);
+ if (e1[0] != '-' || errno != 0)
+ break;
+
+ errno = 0;
+ f->val[1] = strtol(e1 + 1, &e2, 10);
+ if (e2[0] != '\0' || errno != 0)
+ break;
+
+ f->type = RANGE;
+ break;
+ case ',':
+ for (i = 1; isdigit(*p) || *p == ','; p++)
+ if (*p == ',')
+ i++;
+ f->val = emalloc(i * sizeof(*f->val));
+ f->len = i;
+
+ errno = 0;
+ f->val[0] = strtol(field, &e1, 10);
+ if (f->val[0] < low || f->val[0] > high)
+ break;
+
+ for (i = 1; *e1 == ',' && errno == 0; i++) {
+ errno = 0;
+ f->val[i] = strtol(e1 + 1, &e2, 10);
+ e1 = e2;
+ }
+ if (e1[0] != '\0' || errno != 0)
+ break;
+
+ f->type = LIST;
+ break;
+ default:
+ return -1;
+ }
+
+ for (i = 0; i < f->len; i++)
+ if (f->val[i] < low || f->val[i] > high)
+ f->type = ERROR;
+
+ if (f->type == ERROR) {
+ free(f->val);
+ return -1;
+ }
+
+ return 0;
+}
+
+static void
+freecte(struct ctabentry *cte, int nfields)
+{
+ switch (nfields) {
+ case 6:
+ free(cte->cmd);
+ case 5:
+ free(cte->wday.val);
+ case 4:
+ free(cte->mon.val);
+ case 3:
+ free(cte->mday.val);
+ case 2:
+ free(cte->hour.val);
+ case 1:
+ free(cte->min.val);
+ }
+ free(cte);
+}
+
+static void
+unloadentries(void)
+{
+ struct ctabentry *cte, *tmp;
+
+ for (cte = TAILQ_FIRST(&ctabhead); cte; cte = tmp) {
+ tmp = TAILQ_NEXT(cte, entry);
+ TAILQ_REMOVE(&ctabhead, cte, entry);
+ freecte(cte, 6);
+ }
+}
+
+static int
+loadentries(void)
+{
+ struct ctabentry *cte;
+ FILE *fp;
+ char *line = NULL, *p, *col;
+ int r = 0, y;
+ size_t size = 0;
+ ssize_t len;
+ struct fieldlimits {
+ char *name;
+ long min;
+ long max;
+ struct field *f;
+ } flim[] = {
+ { "min", 0, 59, NULL },
+ { "hour", 0, 23, NULL },
+ { "mday", 1, 31, NULL },
+ { "mon", 1, 12, NULL },
+ { "wday", 0, 6, NULL }
+ };
+ size_t x;
+
+ if ((fp = fopen(config, "r")) == NULL) {
+ logerr("error: can't open %s: %s\n", config, strerror(errno));
+ return -1;
+ }
+
+ for (y = 0; (len = getline(&line, &size, fp)) != -1; y++) {
+ p = line;
+ if (line[0] == '#' || line[0] == '\n' || line[0] == '\0')
+ continue;
+
+ cte = emalloc(sizeof(*cte));
+ flim[0].f = &cte->min;
+ flim[1].f = &cte->hour;
+ flim[2].f = &cte->mday;
+ flim[3].f = &cte->mon;
+ flim[4].f = &cte->wday;
+
+ for (x = 0; x < LEN(flim); x++) {
+ do
+ col = strsep(&p, "\t\n ");
+ while (col && col[0] == '\0');
+
+ if (!col || parsefield(col, flim[x].min, flim[x].max, flim[x].f) < 0) {
+ logerr("error: failed to parse `%s' field on line %d\n",
+ flim[x].name, y + 1);
+ freecte(cte, x);
+ r = -1;
+ break;
+ }
+ }
+
+ if (r == -1)
+ break;
+
+ col = strsep(&p, "\n");
+ if (col)
+ while (col[0] == '\t' || col[0] == ' ')
+ col++;
+ if (!col || col[0] == '\0') {
+ logerr("error: missing `cmd' field on line %d\n",
+ y + 1);
+ freecte(cte, 5);
+ r = -1;
+ break;
+ }
+ cte->cmd = estrdup(col);
+
+ TAILQ_INSERT_TAIL(&ctabhead, cte, entry);
+ }
+
+ if (r < 0)
+ unloadentries();
+
+ free(line);
+ fclose(fp);
+
+ return r;
+}
+
+static void
+reloadentries(void)
+{
+ unloadentries();
+ if (loadentries() < 0)
+ logwarn("warning: discarding old crontab entries\n");
+}
+
+static void
+sighandler(int sig)
+{
+ switch (sig) {
+ case SIGCHLD:
+ chldreap = 1;
+ break;
+ case SIGHUP:
+ reload = 1;
+ break;
+ case SIGTERM:
+ quit = 1;
+ break;
+ }
+}
+
+static void
+usage(void)
+{
+ eprintf("usage: %s [-f file] [-n]\n", argv0);
+}
+
+int
+main(int argc, char *argv[])
+{
+ FILE *fp;
+ struct ctabentry *cte;
+ time_t t;
+ struct tm *tm;
+ struct sigaction sa;
+
+ ARGBEGIN {
+ case 'n':
+ nflag = 1;
+ break;
+ case 'f':
+ config = EARGF(usage());
+ break;
+ default:
+ usage();
+ } ARGEND
+
+ if (argc > 0)
+ usage();
+
+ if (nflag == 0) {
+ openlog(argv[0], LOG_CONS | LOG_PID, LOG_CRON);
+ if (daemon(1, 0) < 0) {
+ logerr("error: failed to daemonize %s\n", strerror(errno));
+ return 1;
+ }
+ if ((fp = fopen(pidfile, "w"))) {
+ fprintf(fp, "%d\n", getpid());
+ fclose(fp);
+ }
+ }
+
+ sa.sa_handler = sighandler;
+ sigfillset(&sa.sa_mask);
+ sa.sa_flags = SA_RESTART;
+ sigaction(SIGCHLD, &sa, NULL);
+ sigaction(SIGHUP, &sa, NULL);
+ sigaction(SIGTERM, &sa, NULL);
+
+ loadentries();
+
+ while (1) {
+ t = time(NULL);
+ sleep(60 - t % 60);
+
+ if (quit == 1) {
+ if (nflag == 0)
+ unlink(pidfile);
+ unloadentries();
+ /* Don't wait or kill forked processes, just exit */
+ break;
+ }
+
+ if (reload == 1 || chldreap == 1) {
+ if (reload == 1) {
+ reloadentries();
+ reload = 0;
+ }
+ if (chldreap == 1) {
+ waitjob();
+ chldreap = 0;
+ }
+ continue;
+ }
+
+ TAILQ_FOREACH(cte, &ctabhead, entry) {
+ t = time(NULL);
+ tm = localtime(&t);
+ if (matchentry(cte, tm) == 1)
+ runjob(cte->cmd);
+ }
+ }
+
+ if (nflag == 0)
+ closelog();
+
+ return 0;
+}
generated by cgit v1.2.1 (git 2.18.0) at 2025-10-04 13:44:48 +0000