busybox/runit/runsvdir.c
2007-01-29 22:51:58 +00:00

307 lines
6.0 KiB
C

/* Busyboxed by Denis Vlasenko <vda.linux@googlemail.com> */
/* TODO: depends on runit_lib.c - review and reduce/eliminate */
#include <sys/poll.h>
#include <sys/file.h>
#include "busybox.h"
#include "runit_lib.h"
#define MAXSERVICES 1000
static char *svdir;
static unsigned long dev;
static unsigned long ino;
static struct service {
unsigned long dev;
unsigned long ino;
int pid;
int isgone;
} *sv;
static int svnum;
static int check = 1;
static char *rplog;
static int rploglen;
static int logpipe[2];
static iopause_fd io[1];
static struct taia stamplog;
static int exitsoon;
static int pgrp;
#define usage() bb_show_usage()
static void fatal2_cannot(const char *m1, const char *m2)
{
bb_perror_msg_and_die("%s: fatal: cannot %s%s", svdir, m1, m2);
/* was exiting 100 */
}
static void warn3x(const char *m1, const char *m2, const char *m3)
{
bb_error_msg("%s: warning: %s%s%s", svdir, m1, m2, m3);
}
static void warn2_cannot(const char *m1, const char *m2)
{
warn3x("cannot ", m1, m2);
}
static void warnx(const char *m1)
{
warn3x(m1, "", "");
}
static void s_term(int sig_no)
{
exitsoon = 1;
}
static void s_hangup(int sig_no)
{
exitsoon = 2;
}
static void runsv(int no, const char *name)
{
int pid = fork();
if (pid == -1) {
warn2_cannot("fork for ", name);
return;
}
if (pid == 0) {
/* child */
char *prog[3];
prog[0] = (char*)"runsv";
prog[1] = (char*)name;
prog[2] = NULL;
sig_uncatch(SIGHUP);
sig_uncatch(SIGTERM);
if (pgrp) setsid();
execvp(prog[0], prog);
//pathexec_run(*prog, prog, (char* const*)environ);
fatal2_cannot("start runsv ", name);
}
sv[no].pid = pid;
}
static void runsvdir(void)
{
DIR *dir;
direntry *d;
int i;
struct stat s;
dir = opendir(".");
if (!dir) {
warn2_cannot("open directory ", svdir);
return;
}
for (i = 0; i < svnum; i++)
sv[i].isgone = 1;
errno = 0;
while ((d = readdir(dir))) {
if (d->d_name[0] == '.') continue;
if (stat(d->d_name, &s) == -1) {
warn2_cannot("stat ", d->d_name);
errno = 0;
continue;
}
if (!S_ISDIR(s.st_mode)) continue;
for (i = 0; i < svnum; i++) {
if ((sv[i].ino == s.st_ino) && (sv[i].dev == s.st_dev)) {
sv[i].isgone = 0;
if (!sv[i].pid)
runsv(i, d->d_name);
break;
}
}
if (i == svnum) {
/* new service */
struct service *svnew = realloc(sv, (i+1) * sizeof(*sv));
if (!svnew) {
warn3x("cannot start runsv ", d->d_name,
" too many services");
continue;
}
sv = svnew;
svnum++;
memset(&sv[i], 0, sizeof(sv[i]));
sv[i].ino = s.st_ino;
sv[i].dev = s.st_dev;
//sv[i].pid = 0;
//sv[i].isgone = 0;
runsv(i, d->d_name);
check = 1;
}
}
if (errno) {
warn2_cannot("read directory ", svdir);
closedir(dir);
check = 1;
return;
}
closedir(dir);
/* SIGTERM removed runsv's */
for (i = 0; i < svnum; i++) {
if (!sv[i].isgone)
continue;
if (sv[i].pid)
kill(sv[i].pid, SIGTERM);
sv[i] = sv[--svnum];
check = 1;
}
}
static int setup_log(void)
{
rploglen = strlen(rplog);
if (rploglen < 7) {
warnx("log must have at least seven characters");
return 0;
}
if (pipe(logpipe) == -1) {
warnx("cannot create pipe for log");
return -1;
}
coe(logpipe[1]);
coe(logpipe[0]);
ndelay_on(logpipe[0]);
ndelay_on(logpipe[1]);
if (fd_copy(2, logpipe[1]) == -1) {
warnx("cannot set filedescriptor for log");
return -1;
}
io[0].fd = logpipe[0];
io[0].events = IOPAUSE_READ;
taia_now(&stamplog);
return 1;
}
int runsvdir_main(int argc, char **argv)
{
struct stat s;
time_t mtime = 0;
int wstat;
int curdir;
int pid;
struct taia deadline;
struct taia now;
struct taia stampcheck;
char ch;
int i;
argv++;
if (!argv || !*argv) usage();
if (**argv == '-') {
switch (*(*argv + 1)) {
case 'P': pgrp = 1;
case '-': ++argv;
}
if (!argv || !*argv) usage();
}
sig_catch(SIGTERM, s_term);
sig_catch(SIGHUP, s_hangup);
svdir = *argv++;
if (argv && *argv) {
rplog = *argv;
if (setup_log() != 1) {
rplog = 0;
warnx("log service disabled");
}
}
curdir = open_read(".");
if (curdir == -1)
fatal2_cannot("open current directory", "");
coe(curdir);
taia_now(&stampcheck);
for (;;) {
/* collect children */
for (;;) {
pid = wait_nohang(&wstat);
if (pid <= 0) break;
for (i = 0; i < svnum; i++) {
if (pid == sv[i].pid) {
/* runsv has gone */
sv[i].pid = 0;
check = 1;
break;
}
}
}
taia_now(&now);
if (now.sec.x < (stampcheck.sec.x - 3)) {
/* time warp */
warnx("time warp: resetting time stamp");
taia_now(&stampcheck);
taia_now(&now);
if (rplog) taia_now(&stamplog);
}
if (taia_less(&now, &stampcheck) == 0) {
/* wait at least a second */
taia_uint(&deadline, 1);
taia_add(&stampcheck, &now, &deadline);
if (stat(svdir, &s) != -1) {
if (check || s.st_mtime != mtime
|| s.st_ino != ino || s.st_dev != dev
) {
/* svdir modified */
if (chdir(svdir) != -1) {
mtime = s.st_mtime;
dev = s.st_dev;
ino = s.st_ino;
check = 0;
if (now.sec.x <= (4611686018427387914ULL + (uint64_t)mtime))
sleep(1);
runsvdir();
while (fchdir(curdir) == -1) {
warn2_cannot("change directory, pausing", "");
sleep(5);
}
} else
warn2_cannot("change directory to ", svdir);
}
} else
warn2_cannot("stat ", svdir);
}
if (rplog) {
if (taia_less(&now, &stamplog) == 0) {
write(logpipe[1], ".", 1);
taia_uint(&deadline, 900);
taia_add(&stamplog, &now, &deadline);
}
}
taia_uint(&deadline, check ? 1 : 5);
taia_add(&deadline, &now, &deadline);
sig_block(SIGCHLD);
if (rplog)
iopause(io, 1, &deadline, &now);
else
iopause(0, 0, &deadline, &now);
sig_unblock(SIGCHLD);
if (rplog && (io[0].revents | IOPAUSE_READ))
while (read(logpipe[0], &ch, 1) > 0)
if (ch) {
for (i = 6; i < rploglen; i++)
rplog[i-1] = rplog[i];
rplog[rploglen-1] = ch;
}
switch (exitsoon) {
case 1:
_exit(0);
case 2:
for (i = 0; i < svnum; i++)
if (sv[i].pid)
kill(sv[i].pid, SIGTERM);
_exit(111);
}
}
/* not reached */
return 0;
}