4 our @ISA = qw(Exporter);
5 our @EXPORT = qw(initialisation_complete);
8 use Fcntl qw(F_GETFL F_SETFL O_NONBLOCK);
9 use POSIX qw(_exit setsid);
14 our $env_name = 'PREFORK_INTERP';
21 syslog(LOG_ERR, "$0: prefork [$$]: error: $m");
27 syslog(LOG_INFO, "$0 prefork [$$]: $m, quitting");
31 # Returns in the executor process
32 sub become_monitor () {
33 my $child = fork // fail("fork executor: $!");
36 open ::STDIN , "<& $call_fds[0]" or fail_log("dup for fd0");
37 open ::STDOUT, ">& $call_fds[1]" or fail_log("dup for fd1");
38 open ::STDERR, ">& $call_fds[2]" or fail_log("dup for fd2");
43 #---- monitor [2] ----
44 my $got = waitpid $child, 0 // fail_log("wait for executor: $!");
45 $got == $child or fail_log("wait for esecutor gave $got, expected $child");
47 protocol_write(pack "L", $?);
51 sub close_call_fds () {
59 sub protocol_write ($) {
61 return if (print CALL $d and flush CALL);
62 _exit(0) if $!==EPIPE || $!==ECONNRESET;
63 fail_log("protocol write: $!");
70 return $r if defined $r;
76 sub protocol_read_fail ($) {
78 _exit(0) if $!==ECONNRESET;
79 die("recv $what: $!");
82 sub protocol_exchange () {
89 $r = IO::FDPass::recv(fileno(CALL));
92 protocol_read_fail("fd $_");
98 $r = read(CALL, $len, 4) // protocol_read_fail("message length");
101 $len = unpack "L", $len;
103 $r = read(CALL, $data, $len) // protocol_read_fail("message data ($len)");
104 $r == $len or _exit(0);
106 @ARGV = split /\0/, $data;
107 @ARGV >= 2 or die("message data has too few strings");
108 length(pop(@ARGV)) and die("message data missing trailing nul");
110 while (my $s = shift @ARGV) {
112 $s =~ m/=/ or die("message data env var missing equals");
117 sub initialisation_complete {
120 # if env var not set, we're not running under prefork-interp
121 my @env_params = split /,/, ($ENV{$env_name} // return), 5;
122 croak "$env_name has too few entries" unless @env_params == 5;
124 $num_servers = $opts{max_servers} // 4;
126 #---- setup (pm) [1] ----
128 $socket_path = pop @env_params;
129 foreach (@env_params) {
130 $_ eq ($_+0) or croak "$env_name contains $_, not a number";
132 open LISTEN, "+>&=$env_params[0]" or croak "listen fd: $!";
133 open CALL, "+>&=$env_params[1]" or croak "listen fd: $!";
134 @call_fds = ($env_params[2], $env_params[3], 2);
136 if (!$opts{no_openlog}) {
137 openlog("prefork-interp $0", 'ndelay,nofatal,pid',
138 $opts{log_facility} // 'log_user');
141 open NULL, "+>/dev/null" or croak "open /dev/null: $!";
143 #---- fork for server ----
145 my $child = fork // croak "first fork failed: $!";
147 #---- setup (pm) [2], exits ----
151 #---- server(pm) [1] ----
153 $child = fork // croak "second fork failed: $!";
155 # we are the child, i.e. the one fa-monitor
156 return become_monitor();
160 $children{$child} = 1;
162 # --- server(pm) [2] ----
164 setsid() > 0 or fail_log("setsid: $!");
165 open STDIN, "<&NULL" or fail_log("dup null onto stdin: $!");
166 open STDOUT, ">&NULL" or fail_log("dup null onto stdout: $!");
167 open STDERR, ">&NULL" or fail_log("dup null onto stderr: $!");
172 my $flags = fcntl(LISTEN, F_GETFL, 0)
173 or fail_log("F_GETFL listen socket: $!");
174 $flags |= O_NONBLOCK;
175 fcntl(LISTEN, F_SETFL, $flags)
176 or fail_log("F_SETFL listen socket: $!");
183 my $full = %children >= $num_servers;
184 my $got = waitpid -1, ($full ? 0 : WNOHANG);
187 "$0 prefork [$$]: monitor process [$got] failed with wait status $?");
189 if (!exists $children{$got}) {
191 "$0 prefork [$$]: monitor process [$got] wasn't one of ours?!");
193 delete $children{$got};
197 # select for accepting or housekeeping timeout
199 vec($rbits, fileno(LISTEN), 1) = 1;
201 my $nfound = select($rbits, '', $ebits, ($opts{check_interval} // 86400));
204 if (accept(CALL, LISTEN)) {
205 $child = fork // fail_log("fork for accepted call failed: $!");
207 #---- monitor [1] ----
209 eval { protocol_exchange(); 1; }
210 or fail_log("protocol exchange failed: $@");
211 return become_monitor();
215 $children{$child} = 1;
216 } elsif ($! == EINTR || $! == EAGAIN || $! == EWOULDBLOCK) {
218 syslog(LOG_WARNING, "$0 prefork [$$]: accept failed: $!");
219 if ($errcount > ($opts{max_errors} // 100)) {
221 "$0 prefork [$$]: too many accept failures, quitting");
229 my @st_listen = stat(LISTEN) // fail_log("fstat listening socket: $!");
230 my @st_socket = stat($socket_path) // do {
231 if ($! == ENOENT) { server_quit("socket $socket is ENOENT"); }
232 fail_log("stat socket $socket: $!");
234 if ("@st_listen[0..2]" ne "@st_socket[0..2]") {
235 server_quit("socket $socket is no longer ours");