syscall: more idiomatic cmsghdr space allocation

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

diff --git a/lib/PublicInbox/Syscall.pm b/lib/PublicInbox/Syscall.pm
index e9175ceb9cfac0c3ce504be36962d7c7b9e51941..cc282f9ff6bb3a3079913f1a8ecb1005fc61d0be 100644 (file)
--- a/lib/PublicInbox/Syscall.pm
+++ b/lib/PublicInbox/Syscall.pm
@@ -3,7 +3,8 @@
 # fix upstream regressions in 0.25.
 #
 # See devel/syscall-list in the public-inbox source tree for maintenance
-# <https://80x24.org/public-inbox.git>
+# <https://80x24.org/public-inbox.git>, and machines from the GCC Farm:
+# <https://cfarm.tetaneutral.net/>
 #
 # This license differs from the rest of public-inbox
 #
@@ -150,6 +151,8 @@ if ($^O eq "linux") {
        $SYS_renameat2 //= 345;
        $SFD_CLOEXEC = 020000000;
        $SYS_fstatfs = 158;
+       $SYS_sendmsg = 114;
+       $SYS_recvmsg = 113;
        $FS_IOC_GETFLAGS = 0x40086601;
        $FS_IOC_SETFLAGS = 0x80086602;
     } elsif ($machine =~ m/^parisc/) {
@@ -166,6 +169,8 @@ if ($^O eq "linux") {
         $SYS_signalfd4 = 313;
        $SYS_renameat2 //= 357;
        $SYS_fstatfs = 100;
+       $SYS_sendmsg = 341;
+       $SYS_recvmsg = 342;
        $FS_IOC_GETFLAGS = 0x40086601;
        $FS_IOC_SETFLAGS = 0x80086602;
     } elsif ($machine eq "ppc") {
@@ -178,7 +183,7 @@ if ($^O eq "linux") {
        $SYS_fstatfs = 100;
        $FS_IOC_GETFLAGS = 0x40086601;
        $FS_IOC_SETFLAGS = 0x80086602;
-    } elsif ($machine =~ m/^s390/) {
+    } elsif ($machine =~ m/^s390/) { # untested, no machine on cfarm
         $SYS_epoll_create = 249;
         $SYS_epoll_ctl    = 250;
         $SYS_epoll_wait   = 251;
@@ -186,13 +191,15 @@ if ($^O eq "linux") {
         $SYS_signalfd4 = 322;
        $SYS_renameat2 //= 347;
        $SYS_fstatfs = 100;
-    } elsif ($machine eq "ia64") {
+       $SYS_sendmsg = 370;
+       $SYS_recvmsg = 372;
+    } elsif ($machine eq 'ia64') { # untested, no machine on cfarm
         $SYS_epoll_create = 1243;
         $SYS_epoll_ctl    = 1244;
         $SYS_epoll_wait   = 1245;
         $u64_mod_8        = 1;
         $SYS_signalfd4 = 289;
-    } elsif ($machine eq "alpha") {
+    } elsif ($machine eq "alpha") { # untested, no machine on cfarm
         # natural alignment, ints are 32-bits
         $SYS_epoll_create = 407;
         $SYS_epoll_ctl    = 408;
@@ -200,7 +207,7 @@ if ($^O eq "linux") {
         $u64_mod_8        = 1;
         $SYS_signalfd4 = 484;
        $SFD_CLOEXEC = 010000000;
-    } elsif ($machine eq "aarch64") {
+    } elsif ($machine eq 'aarch64' || $machine eq 'loongarch64') {
         $SYS_epoll_create = 20;  # (sys_epoll_create1)
         $SYS_epoll_ctl    = 21;
         $SYS_epoll_wait   = 22;  # (sys_epoll_pwait)
@@ -209,10 +216,11 @@ if ($^O eq "linux") {
         $SYS_signalfd4 = 74;
        $SYS_renameat2 //= 276;
        $SYS_fstatfs = 44;
+       $SYS_sendmsg = 211;
+       $SYS_recvmsg = 212;
        $FS_IOC_GETFLAGS = 0x80086601;
        $FS_IOC_SETFLAGS = 0x40086602;
-    } elsif ($machine =~ m/arm(v\d+)?.*l/) {
-        # ARM OABI
+    } elsif ($machine =~ m/arm(v\d+)?.*l/) { # ARM OABI (untested on cfarm)
         $SYS_epoll_create = 250;
         $SYS_epoll_ctl    = 251;
         $SYS_epoll_wait   = 252;
@@ -220,7 +228,9 @@ if ($^O eq "linux") {
         $SYS_signalfd4 = 355;
        $SYS_renameat2 //= 382;
        $SYS_fstatfs = 100;
-    } elsif ($machine =~ m/^mips64/) {
+       $SYS_sendmsg = 296;
+       $SYS_recvmsg = 297;
+    } elsif ($machine =~ m/^mips64/) { # cfarm only has 32-bit userspace
         $SYS_epoll_create = 5207;
         $SYS_epoll_ctl    = 5208;
         $SYS_epoll_wait   = 5209;
@@ -228,9 +238,11 @@ if ($^O eq "linux") {
         $SYS_signalfd4 = 5283;
        $SYS_renameat2 //= 5311;
        $SYS_fstatfs = 5135;
+       $SYS_sendmsg = 5045;
+       $SYS_recvmsg = 5046;
        $FS_IOC_GETFLAGS = 0x40046601;
        $FS_IOC_SETFLAGS = 0x80046602;
-    } elsif ($machine =~ m/^mips/) {
+    } elsif ($machine =~ m/^mips/) { # 32-bit, tested on mips64 cfarm machine
         $SYS_epoll_create = 4248;
         $SYS_epoll_ctl    = 4249;
         $SYS_epoll_wait   = 4250;
@@ -238,6 +250,8 @@ if ($^O eq "linux") {
         $SYS_signalfd4 = 4324;
        $SYS_renameat2 //= 4351;
        $SYS_fstatfs = 4100;
+       $SYS_sendmsg = 4179;
+       $SYS_recvmsg = 4177;
        $FS_IOC_GETFLAGS = 0x40046601;
        $FS_IOC_SETFLAGS = 0x80046602;
     } else {
@@ -404,6 +418,7 @@ sub CMSG_ALIGN ($) { ($_[0] + SIZEOF_size_t - 1) & ~(SIZEOF_size_t - 1) }
 use constant CMSG_ALIGN_SIZEOF_cmsghdr => CMSG_ALIGN(SIZEOF_cmsghdr);
 sub CMSG_SPACE ($) { CMSG_ALIGN($_[0]) + CMSG_ALIGN_SIZEOF_cmsghdr }
 sub CMSG_LEN ($) { CMSG_ALIGN_SIZEOF_cmsghdr + $_[0] }
+use constant msg_controllen => CMSG_SPACE(10 * SIZEOF_int) + 16; # 10 FDs
 
 if (defined($SYS_sendmsg) && defined($SYS_recvmsg)) {
 no warnings 'once';
@@ -443,7 +458,7 @@ no warnings 'once';
 *recv_cmd4 = sub ($$$) {
        my ($sock, undef, $len) = @_;
        vec($_[1], ($len + 1) * 8, 1) = 0;
-       vec(my $cmsghdr = '', 256 * 8 - 1, 1) = 1;
+       my $cmsghdr = "\0" x msg_controllen; # 10 * sizeof(int)
        my $iov = pack('P'.TMPL_size_t, $_[1], $len);
        my $mh = pack('PL' . # msg_name, msg_namelen (socklen_t (U32))
                        BYTES_4_hole . # 4-byte padding on 64-bit
@@ -454,7 +469,7 @@ no warnings 'once';
                        @BYTES_4_hole,
                        $iov, 1, # msg_iov, msg_iovlen
                        $cmsghdr, # msg_control
-                       256, # msg_controllen
+                       msg_controllen,
                        0); # msg_flags
        my $r = syscall($SYS_recvmsg, fileno($sock), $mh, 0);
        return (undef) if $r < 0; # $! set