#!/usr/bin/env perl
# Copyright 2018 The Go Authors. All rights reserved.
# Use of this source code is governed by a BSD-style
# license that can be found in the LICENSE file.
# This program reads a file containing function prototypes
# (like syscall_aix.go) and generates system call bodies.
# The prototypes are marked by lines beginning with "//sys"
# and read like func declarations if //sys is replaced by func, but:
# * The parameter lists must give a name for each argument.
# This includes return parameters.
# * The parameter lists must give a type for each argument:
# the (x, y, z int) shorthand is not allowed.
# * If the return parameter is an error number, it must be named err.
# * If go func name needs to be different than its libc name,
# * or the function is not in libc, name could be specified
# * at the end, after "=" sign, like
# //sys getsockopt(s int, level int, name int, val uintptr, vallen *_Socklen) (err error) = libsocket.getsockopt
use strict;
my $cmdline = "mksyscall_aix_ppc.pl " . join(' ', @ARGV);
my $errors = 0;
my $_32bit = "";
my $tags = ""; # build tags
my $aix = 0;
my $solaris = 0;
binmode STDOUT;
if($ARGV[0] eq "-b32") {
$_32bit = "big-endian";
shift;
} elsif($ARGV[0] eq "-l32") {
$_32bit = "little-endian";
shift;
}
if($ARGV[0] eq "-aix") {
$aix = 1;
shift;
}
if($ARGV[0] eq "-tags") {
shift;
$tags = $ARGV[0];
shift;
}
if($ARGV[0] =~ /^-/) {
print STDERR "usage: mksyscall_aix.pl [-b32 | -l32] [-tags x,y] [file ...]\n";
exit 1;
}
sub parseparamlist($) {
my ($list) = @_;
$list =~ s/^\s*//;
$list =~ s/\s*$//;
if($list eq "") {
return ();
}
return split(/\s*,\s*/, $list);
}
sub parseparam($) {
my ($p) = @_;
if($p !~ /^(\S*) (\S*)$/) {
print STDERR "$ARGV:$.: malformed parameter: $p\n";
$errors = 1;
return ("xx", "int");
}
return ($1, $2);
}
my $package = "";
my $text = "";
my $c_extern = "/*\n#include <stdint.h>\n#include <stddef.h>\n";
my @vars = ();
while(<>) {
chomp;
s/\s+/ /g;
s/^\s+//;
s/\s+$//;
$package = $1 if !$package && /^package (\S+)$/;
my $nonblock = /^\/\/sysnb /;
next if !/^\/\/sys / && !$nonblock;
# Line must be of the form
# func Open(path string, mode int, perm int) (fd int, err error)
# Split into name, in params, out params.
if(!/^\/\/sys(nb)? (\w+)\(([^()]*)\)\s*(?:\(([^()]+)\))?\s*(?:=\s*(?:(\w*)\.)?(\w*))?$/) {
print STDERR "$ARGV:$.: malformed //sys declaration\n";
$errors = 1;
next;
}
my ($nb, $func, $in, $out, $modname, $sysname) = ($1, $2, $3, $4, $5, $6);
# Split argument lists on comma.
my @in = parseparamlist($in);
my @out = parseparamlist($out);
$in = join(', ', @in);
$out = join(', ', @out);
# Try in vain to keep people from editing this file.
# The theory is that they jump into the middle of the file
# without reading the header.
$text .= "// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n\n";
# Check if value return, err return available
my $errvar = "";
my $retvar = "";
my $rettype = "";
foreach my $p (@out) {
my ($name, $type) = parseparam($p);
if($type eq "error") {
$errvar = $name;
} else {
$retvar = $name;
$rettype = $type;
}
}
# System call name.
#if($func ne "fcntl") {
if($sysname eq "") {
$sysname = "$func";
}
$sysname =~ s/([a-z])([A-Z])/${1}_$2/g;
$sysname =~ y/A-Z/a-z/; # All libc functions are lowercase.
my $C_rettype = "";
if($rettype eq "unsafe.Pointer") {
$C_rettype = "uintptr_t";
} elsif($rettype eq "uintptr") {
$C_rettype = "uintptr_t";
} elsif($rettype =~ /^_/) {
$C_rettype = "uintptr_t";
} elsif($rettype eq "int") {
$C_rettype = "int";
} elsif($rettype eq "int32") {
$C_rettype = "int";
} elsif($rettype eq "int64") {
$C_rettype = "long long";
} elsif($rettype eq "uint32") {
$C_rettype = "unsigned int";
} elsif($rettype eq "uint64") {
$C_rettype = "unsigned long long";
} else {
$C_rettype = "int";
}
if($sysname eq "exit") {
$C_rettype = "void";
}
# Change types to c
my @c_in = ();
foreach my $p (@in) {
my ($name, $type) = parseparam($p);
if($type =~ /^\*/) {
push @c_in, "uintptr_t";
} elsif($type eq "string") {
push @c_in, "uintptr_t";
} elsif($type =~ /^\[\](.*)/) {
push @c_in, "uintptr_t", "size_t";
} elsif($type eq "unsafe.Pointer") {
push @c_in, "uintptr_t";
} elsif($type eq "uintptr") {
push @c_in, "uintptr_t";
} elsif($type =~ /^_/) {
push @c_in, "uintptr_t";
} elsif($type eq "int") {
push @c_in, "int";
} elsif($type eq "int32") {
push @c_in, "int";
} elsif($type eq "int64") {
push @c_in, "long long";
} elsif($type eq "uint32") {
push @c_in, "unsigned int";
} elsif($type eq "uint64") {
push @c_in, "unsigned long long";
} else {
push @c_in, "int";
}
}
if ($func ne "fcntl" && $func ne "FcntlInt" && $func ne "readlen" && $func ne "writelen") {
# Imports of system calls from libc
$c_extern .= "$C_rettype $sysname";
my $c_in = join(', ', @c_in);
$c_extern .= "($c_in);\n";
}
# So file name.
if($aix) {
if($modname eq "") {
$modname = "libc.a/shr_64.o";
} else {
print STDERR "$func: only syscall using libc are available\n";
$errors = 1;
next;
}
}
my $strconvfunc = "C.CString";
my $strconvtype = "*byte";
# Go function header.
if($out ne "") {
$out = " ($out)";
}
if($text ne "") {
$text .= "\n"
}
$text .= sprintf "func %s(%s)%s {\n", $func, join(', ', @in), $out ;
# Prepare arguments to call.
my @args = ();
my $n = 0;
my $arg_n = 0;
foreach my $p (@in) {
my ($name, $type) = parseparam($p);
if($type =~ /^\*/) {
push @args, "C.uintptr_t(uintptr(unsafe.Pointer($name)))";
} elsif($type eq "string" && $errvar ne "") {
$text .= "\t_p$n := uintptr(unsafe.Pointer($strconvfunc($name)))\n";
push @args, "C.uintptr_t(_p$n)";
$n++;
} elsif($type eq "string") {
print STDERR "$ARGV:$.: $func uses string arguments, but has no error return\n";
$text .= "\t_p$n := uintptr(unsafe.Pointer($strconvfunc($name)))\n";
push @args, "C.uintptr_t(_p$n)";
$n++;
} elsif($type =~ /^\[\](.*)/) {
# Convert slice into pointer, length.
# Have to be careful not to take address of &a[0] if len == 0:
# pass nil in that case.
$text .= "\tvar _p$n *$1\n";
$text .= "\tif len($name) > 0 {\n\t\t_p$n = \&$name\[0]\n\t}\n";
push @args, "C.uintptr_t(uintptr(unsafe.Pointer(_p$n)))";
$n++;
$text .= "\tvar _p$n int\n";
$text .= "\t_p$n = len($name)\n";
push @args, "C.size_t(_p$n)";
$n++;
} elsif($type eq "int64" && $_32bit ne "") {
if($_32bit eq "big-endian") {
push @args, "uintptr($name >> 32)", "uintptr($name)";
} else {
push @args, "uintptr($name)", "uintptr($name >> 32)";
}
$n++;
} elsif($type eq "bool") {
$text .= "\tvar _p$n uint32\n";
$text .= "\tif $name {\n\t\t_p$n = 1\n\t} else {\n\t\t_p$n = 0\n\t}\n";
push @args, "_p$n";
$n++;
} elsif($type =~ /^_/) {
push @args, "C.uintptr_t(uintptr($name))";
} elsif($type eq "unsafe.Pointer") {
push @args, "C.uintptr_t(uintptr($name))";
} elsif($type eq "int") {
if (($arg_n == 2) && (($func eq "readlen") || ($func eq "writelen"))) {
push @args, "C.size_t($name)";
} elsif ($arg_n == 0 && $func eq "fcntl") {
push @args, "C.uintptr_t($name)";
} elsif (($arg_n == 2) && (($func eq "fcntl") || ($func eq "FcntlInt"))) {
push @args, "C.uintptr_t($name)";
} else {
push @args, "C.int($name)";
}
} elsif($type eq "int32") {
push @args, "C.int($name)";
} elsif($type eq "int64") {
push @args, "C.longlong($name)";
} elsif($type eq "uint32") {
push @args, "C.uint($name)";
} elsif($type eq "uint64") {
push @args, "C.ulonglong($name)";
} elsif($type eq "uintptr") {
push @args, "C.uintptr_t($name)";
} else {
push @args, "C.int($name)";
}
$arg_n++;
}
my $nargs = @args;
# Determine which form to use; pad args with zeros.
if ($nonblock) {
}
my $args = join(', ', @args);
my $call = "";
if ($sysname eq "exit") {
if ($errvar ne "") {
$call .= "er :=";
} else {
$call .= "";
}
} elsif ($errvar ne "") {
$call .= "r0,er :=";
} elsif ($retvar ne "") {
$call .= "r0,_ :=";
} else {
$call .= ""
}
$call .= "C.$sysname($args)";
# Assign return values.
my $body = "";
my $failexpr = "";
for(my $i=0; $i<@out; $i++) {
my $p = $out[$i];
my ($name, $type) = parseparam($p);
my $reg = "";
if($name eq "err") {
$reg = "e1";
} else {
$reg = "r0";
}
if($reg ne "e1" ) {
$body .= "\t$name = $type($reg)\n";
}
}
# verify return
if ($sysname ne "exit" && $errvar ne "") {
if ($C_rettype =~ /^uintptr/) {
$body .= "\tif \(uintptr\(r0\) ==\^uintptr\(0\) && er != nil\) {\n";
$body .= "\t\t$errvar = er\n";
$body .= "\t}\n";
} else {
$body .= "\tif \(r0 ==-1 && er != nil\) {\n";
$body .= "\t\t$errvar = er\n";
$body .= "\t}\n";
}
} elsif ($errvar ne "") {
$body .= "\tif \(er != nil\) {\n";
$body .= "\t\t$errvar = er\n";
$body .= "\t}\n";
}
$text .= "\t$call\n";
$text .= $body;
$text .= "\treturn\n";
$text .= "}\n";
}
if($errors) {
exit 1;
}
print <<EOF;
// $cmdline
// Code generated by the command above; see README.md. DO NOT EDIT.
// +build $tags
package $package
$c_extern
*/
import "C"
import (
"unsafe"
)
EOF
print "import \"golang.org/x/sys/unix\"\n" if $package ne "unix";
chomp($_=<<EOF);
$text
EOF
print $_;
exit 0;