sbase

suckless unix tools
git clone git://git.2f30.org/sbase.git
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commit 8d2c5dd9a33fd240aaf24d21ad6954a2e8d4accd
parent 296af80dbae381898dcee762ecbe36a36079fa66
Author: sin <sin@2f30.org>
Date:   Tue Dec  9 16:04:14 +0000

Import crond from http://git.2f30.org/scron/tree/

Diffstat:
LICENSE | 1+
Makefile | 1+
crond.c | 530+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 532 insertions(+), 0 deletions(-)
diff --git a/LICENSE b/LICENSE @@ -30,6 +30,7 @@ MIT/X Consortium License © 2014 Jeffrey Picard <jeff@jeffreypicard.com> © 2014 Evan Gates <evan.gates@gmail.com> © 2014 Michael Forney <mforney@mforney.org> +© 2014 Ari Malinen <ari.malinen@gmail.com> Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), diff --git a/Makefile b/Makefile @@ -69,6 +69,7 @@ BIN =\ cols\ comm\ cp\ + crond\ cut\ date\ dirname\ diff --git a/crond.c b/crond.c @@ -0,0 +1,530 @@ +/* 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 <string.h> +#include <syslog.h> +#include <time.h> +#include <unistd.h> + +#include "arg.h" +#include "queue.h" + +#define VERSION "0.3.2" + +#define LEN(x) (sizeof (x) / sizeof *(x)) + +struct field { + /* [low, high] */ + long low; + long high; + /* for every `div' units */ + long div; +}; + +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; +}; + +char *argv0; +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 * +emalloc(size_t size) +{ + void *p; + p = malloc(size); + if (!p) { + logerr("error: out of memory\n"); + if (nflag == 0) + unlink(pidfile); + exit(EXIT_FAILURE); + } + return p; +} + +static char * +estrdup(const char *s) +{ + char *p; + + p = strdup(s); + if (!p) { + logerr("error: out of memory\n"); + if (nflag == 0) + unlink(pidfile); + exit(EXIT_FAILURE); + } + return p; +} + +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; + } + } + + pid = fork(); + if (pid < 0) { + logerr("error: failed to fork job: %s time: %s", + cmd, ctime(&t)); + return; + } else if (pid == 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(EXIT_FAILURE); + } else { + 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; + + for (i = 0; i < LEN(matchtbl); i++) { + if (matchtbl[i].f->high == -1) { + if (matchtbl[i].f->low == -1) { + continue; + } else if (matchtbl[i].f->div > 0) { + if (matchtbl[i].tm > 0) { + if (matchtbl[i].tm % matchtbl[i].f->div == 0) + continue; + } else { + if (matchtbl[i].len % matchtbl[i].f->div == 0) + continue; + } + } else if (matchtbl[i].f->low == matchtbl[i].tm) { + continue; + } + } else if (matchtbl[i].f->low <= matchtbl[i].tm && + matchtbl[i].f->high >= matchtbl[i].tm) { + continue; + } + break; + } + if (i != LEN(matchtbl)) + return 0; + return 1; +} + +static int +parsefield(const char *field, long low, long high, struct field *f) +{ + long min, max, div; + char *e1, *e2; + + if (strcmp(field, "*") == 0) { + f->low = -1; + f->high = -1; + return 0; + } + + div = -1; + max = -1; + min = strtol(field, &e1, 10); + + switch (e1[0]) { + case '-': + e1++; + errno = 0; + max = strtol(e1, &e2, 10); + if (e2[0] != '\0' || errno != 0) + return -1; + break; + case '*': + e1++; + if (e1[0] != '/') + return -1; + e1++; + errno = 0; + div = strtol(e1, &e2, 10); + if (e2[0] != '\0' || errno != 0) + return -1; + break; + case '\0': + break; + default: + return -1; + } + + if (min < low || min > high) + return -1; + if (max != -1) + if (max < low || max > high) + return -1; + if (div != -1) + if (div < low || div > high) + return -1; + + f->low = min; + f->high = max; + f->div = div; + return 0; +} + +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); + free(cte->cmd); + free(cte); + } +} + +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; + + 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)); + + col = strsep(&p, "\t"); + if (!col || parsefield(col, 0, 59, &cte->min) < 0) { + logerr("error: failed to parse `min' field on line %d\n", + y + 1); + free(cte); + r = -1; + break; + } + + col = strsep(&p, "\t"); + if (!col || parsefield(col, 0, 23, &cte->hour) < 0) { + logerr("error: failed to parse `hour' field on line %d\n", + y + 1); + free(cte); + r = -1; + break; + } + + col = strsep(&p, "\t"); + if (!col || parsefield(col, 1, 31, &cte->mday) < 0) { + logerr("error: failed to parse `mday' field on line %d\n", + y + 1); + free(cte); + r = -1; + break; + } + + col = strsep(&p, "\t"); + if (!col || parsefield(col, 1, 12, &cte->mon) < 0) { + logerr("error: failed to parse `mon' field on line %d\n", + y + 1); + free(cte); + r = -1; + break; + } + + col = strsep(&p, "\t"); + if (!col || parsefield(col, 0, 6, &cte->wday) < 0) { + logerr("error: failed to parse `wday' field on line %d\n", + y + 1); + free(cte); + r = -1; + break; + } + + col = strsep(&p, "\n"); + if (!col) { + logerr("error: missing `cmd' field on line %d\n", + y + 1); + free(cte); + 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) +{ + fprintf(stderr, "usage: %s [-f file] [-n]\n", argv0); + fprintf(stderr, " -f config file\n"); + fprintf(stderr, " -n do not daemonize\n"); + exit(EXIT_FAILURE); +} + +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 EXIT_FAILURE; + } + 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 EXIT_SUCCESS; +}