send and receive all 3 FDs at once

[public-inbox.git] / lib / PublicInbox / Spawn.pm

diff --git a/lib/PublicInbox/Spawn.pm b/lib/PublicInbox/Spawn.pm
index 4ca94b9f43ff45033345c16b6d236b9f02e3da1b..61e954338ef2f285056feee6c917401630ce9760 100644 (file)
--- a/lib/PublicInbox/Spawn.pm
+++ b/lib/PublicInbox/Spawn.pm
@@ -207,56 +207,67 @@ my $fdpass = <<'FDPASS';
 #include <sys/socket.h>
 
 #if defined(CMSG_SPACE) && defined(CMSG_LEN)
+struct my_3fds { int fds[3]; };
 union my_cmsg {
        struct cmsghdr hdr;
-       char pad[sizeof(struct cmsghdr)+8+sizeof(int)+8];
+       char pad[sizeof(struct cmsghdr)+ 8 + sizeof(struct my_3fds) + 8];
 };
 
-int send_fd(int sockfd, int fd)
+int send_3fds(int sockfd, int infd, int outfd, int errfd)
 {
        struct msghdr msg = { 0 };
        struct iovec iov;
        union my_cmsg cmsg = { 0 };
+       int *fdp;
+       size_t i;
 
-       iov.iov_base = &msg.msg_namelen;
+       iov.iov_base = &msg.msg_namelen; /* whatever */
        iov.iov_len = 1;
        msg.msg_iov = &iov;
        msg.msg_iovlen = 1;
        msg.msg_control = &cmsg.hdr;
-       msg.msg_controllen = CMSG_SPACE(sizeof(int));
+       msg.msg_controllen = CMSG_SPACE(sizeof(struct my_3fds));
 
        cmsg.hdr.cmsg_level = SOL_SOCKET;
        cmsg.hdr.cmsg_type = SCM_RIGHTS;
-       cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(int));
-       *(int *)CMSG_DATA(&cmsg.hdr) = fd;
-
+       cmsg.hdr.cmsg_len = CMSG_LEN(sizeof(struct my_3fds));
+       fdp = (int *)CMSG_DATA(&cmsg.hdr);
+       *fdp++ = infd;
+       *fdp++ = outfd;
+       *fdp++ = errfd;
        return sendmsg(sockfd, &msg, 0) >= 0;
 }
 
-int recv_fd(int sockfd)
+void recv_3fds(int sockfd)
 {
        union my_cmsg cmsg = { 0 };
        struct msghdr msg = { 0 };
        struct iovec iov;
-       int fd = -1;
+       size_t i;
+       Inline_Stack_Vars;
 
-       iov.iov_base = &msg.msg_namelen;
+       iov.iov_base = &msg.msg_namelen; /* whatever */
        iov.iov_len = 1;
        msg.msg_iov = &iov;
        msg.msg_iovlen = 1;
        msg.msg_control = &cmsg.hdr;
-       msg.msg_controllen = CMSG_SPACE(sizeof(int));
+       msg.msg_controllen = CMSG_SPACE(sizeof(struct my_3fds));
 
        if (recvmsg(sockfd, &msg, 0) <= 0)
-               return -1;
+               return;
 
        errno = EDOM;
+       Inline_Stack_Reset;
        if (cmsg.hdr.cmsg_level == SOL_SOCKET &&
                        cmsg.hdr.cmsg_type == SCM_RIGHTS &&
-                       cmsg.hdr.cmsg_len == CMSG_LEN(sizeof(int)))
-               fd = *(int *)CMSG_DATA(&cmsg.hdr);
+                       cmsg.hdr.cmsg_len == CMSG_LEN(sizeof(struct my_3fds))) {
+               int *fdp = (int *)CMSG_DATA(&cmsg.hdr);
+               size_t i;
 
-       return fd;
+               for (i = 0; i < 3; i++)
+                       Inline_Stack_Push(sv_2mortal(newSViv(*fdp++)));
+       }
+       Inline_Stack_Done;
 }
 #endif /* defined(CMSG_SPACE) && defined(CMSG_LEN) */
 FDPASS
@@ -275,7 +286,8 @@ if (defined $vfork_spawn) {
                my $f = "$inline_dir/.public-inbox.lock";
                open my $fh, '>', $f or die "failed to open $f: $!\n";
                flock($fh, LOCK_EX) or die "LOCK_EX failed on $f: $!\n";
-               eval 'use Inline C => $vfork_spawn . $fdpass . $set_nodatacow';
+               eval 'use Inline C => $vfork_spawn.$fdpass.$set_nodatacow';
+                       # . ', BUILD_NOISY => 1';
                my $err = $@;
                my $ndc_err;
                if ($err && $set_nodatacow) { # missing Linux kernel headers
@@ -303,12 +315,15 @@ unless ($set_nodatacow) {
        *nodatacow_fd = \&PublicInbox::NDC_PP::nodatacow_fd;
        *nodatacow_dir = \&PublicInbox::NDC_PP::nodatacow_dir;
 }
-unless (__PACKAGE__->can('recv_fd')) {
+unless (__PACKAGE__->can('recv_3fds')) {
        eval { # try the XS IO::FDPass package
                require IO::FDPass;
                no warnings 'once';
-               *recv_fd = \&IO::FDPass::recv;
-               *send_fd = \&IO::FDPass::send;
+               *recv_3fds = sub { map { IO::FDPass::recv($_[0]) } (0..2) };
+               *send_3fds = sub ($$$$) {
+                       my $sockfd = shift;
+                       IO::FDPass::send($sockfd, shift) for (0..2);
+               };
        };
 }