vendor/golang.org/x/sys/unix/mksyscall.pl - gddo - Git at Google

 #!/usr/bin/env perl
 # Copyright 2009 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_darwin.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 errno.

 # A line beginning with //sysnb is like //sys, except that the
 # goroutine will not be suspended during the execution of the system
 # call.  This must only be used for system calls which can never
 # block, as otherwise the system call could cause all goroutines to
 # hang.

 use strict;

 my $cmdline = "mksyscall.pl " . join(' ', @ARGV);
 my $errors = 0;
 my $_32bit = "";
 my $plan9 = 0;
 my $openbsd = 0;
 my $netbsd = 0;
 my $dragonfly = 0;
 my $arm = 0; # 64-bit value should use (even, odd)-pair
 my $tags = "";  # build tags

 if($ARGV[0] eq "-b32") {
 	$_32bit = "big-endian";
 	shift;
 } elsif($ARGV[0] eq "-l32") {
 	$_32bit = "little-endian";
 	shift;
 }
 if($ARGV[0] eq "-plan9") {
 	$plan9 = 1;
 	shift;
 }
 if($ARGV[0] eq "-openbsd") {
 	$openbsd = 1;
 	shift;
 }
 if($ARGV[0] eq "-netbsd") {
 	$netbsd = 1;
 	shift;
 }
 if($ARGV[0] eq "-dragonfly") {
 	$dragonfly = 1;
 	shift;
 }
 if($ARGV[0] eq "-arm") {
 	$arm = 1;
 	shift;
 }
 if($ARGV[0] eq "-tags") {
 	shift;
 	$tags = $ARGV[0];
 	shift;
 }

 if($ARGV[0] =~ /^-/) {
 	print STDERR "usage: mksyscall.pl [-b32 | -l32] [-tags x,y] [file ...]\n";
 	exit 1;
 }

 # Check that we are using the new build system if we should
 if($ENV{'GOOS'} eq "linux" && $ENV{'GOARCH'} ne "sparc64") {
 	if($ENV{'GOLANG_SYS_BUILD'} ne "docker") {
 		print STDERR "In the new build system, mksyscall should not be called directly.\n";
 		print STDERR "See README.md\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 $text = "";
 while(<>) {
 	chomp;
 	s/\s+/ /g;
 	s/^\s+//;
 	s/\s+$//;
 	my $nonblock = /^\/\/sysnb /;
 	next if !/^\/\/sys / && !$nonblock;

 	# Line must be of the form
 	#	func Open(path string, mode int, perm int) (fd int, errno error)
 	# Split into name, in params, out params.
 	if(!/^\/\/sys(nb)? (\w+)\(([^()]*)\)\s*(?:\(([^()]+)\))?\s*(?:=\s*((?i)SYS_[A-Z0-9_]+))?$/) {
 		print STDERR "$ARGV:$.: malformed //sys declaration\n";
 		$errors = 1;
 		next;
 	}
 	my ($func, $in, $out, $sysname) = ($2, $3, $4, $5);

 	# Split argument lists on comma.
 	my @in = parseparamlist($in);
 	my @out = parseparamlist($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";

 	# Go function header.
 	my $out_decl = @out ? sprintf(" (%s)", join(', ', @out)) : "";
 	$text .= sprintf "func %s(%s)%s {\n", $func, join(', ', @in), $out_decl;

 	# Check if err return available
 	my $errvar = "";
 	foreach my $p (@out) {
 		my ($name, $type) = parseparam($p);
 		if($type eq "error") {
 			$errvar = $name;
 			last;
 		}
 	}

 	# Prepare arguments to Syscall.
 	my @args = ();
 	my $n = 0;
 	foreach my $p (@in) {
 		my ($name, $type) = parseparam($p);
 		if($type =~ /^\*/) {
 			push @args, "uintptr(unsafe.Pointer($name))";
 		} elsif($type eq "string" && $errvar ne "") {
 			$text .= "\tvar _p$n *byte\n";
 			$text .= "\t_p$n, $errvar = BytePtrFromString($name)\n";
 			$text .= "\tif $errvar != nil {\n\t\treturn\n\t}\n";
 			push @args, "uintptr(unsafe.Pointer(_p$n))";
 			$n++;
 		} elsif($type eq "string") {
 			print STDERR "$ARGV:$.: $func uses string arguments, but has no error return\n";
 			$text .= "\tvar _p$n *byte\n";
 			$text .= "\t_p$n, _ = BytePtrFromString($name)\n";
 			push @args, "uintptr(unsafe.Pointer(_p$n))";
 			$n++;
 		} elsif($type =~ /^\[\](.*)/) {
 			# Convert slice into pointer, length.
 			# Have to be careful not to take address of &a[0] if len == 0:
 			# pass dummy pointer in that case.
 			# Used to pass nil, but some OSes or simulators reject write(fd, nil, 0).
 			$text .= "\tvar _p$n unsafe.Pointer\n";
 			$text .= "\tif len($name) > 0 {\n\t\t_p$n = unsafe.Pointer(\&${name}[0])\n\t}";
 			$text .= " else {\n\t\t_p$n = unsafe.Pointer(&_zero)\n\t}";
 			$text .= "\n";
 			push @args, "uintptr(_p$n)", "uintptr(len($name))";
 			$n++;
 		} elsif($type eq "int64" && ($openbsd || $netbsd)) {
 			push @args, "0";
 			if($_32bit eq "big-endian") {
 				push @args, "uintptr($name>>32)", "uintptr($name)";
 			} elsif($_32bit eq "little-endian") {
 				push @args, "uintptr($name)", "uintptr($name>>32)";
 			} else {
 				push @args, "uintptr($name)";
 			}
 		} elsif($type eq "int64" && $dragonfly) {
 			if ($func !~ /^extp(read|write)/i) {
 				push @args, "0";
 			}
 			if($_32bit eq "big-endian") {
 				push @args, "uintptr($name>>32)", "uintptr($name)";
 			} elsif($_32bit eq "little-endian") {
 				push @args, "uintptr($name)", "uintptr($name>>32)";
 			} else {
 				push @args, "uintptr($name)";
 			}
 		} elsif($type eq "int64" && $_32bit ne "") {
 			if(@args % 2 && $arm) {
 				# arm abi specifies 64-bit argument uses
 				# (even, odd) pair
 				push @args, "0"
 			}
 			if($_32bit eq "big-endian") {
 				push @args, "uintptr($name>>32)", "uintptr($name)";
 			} else {
 				push @args, "uintptr($name)", "uintptr($name>>32)";
 			}
 		} else {
 			push @args, "uintptr($name)";
 		}
 	}

 	# Determine which form to use; pad args with zeros.
 	my $asm = "Syscall";
 	if ($nonblock) {
 		$asm = "RawSyscall";
 	}
 	if(@args <= 3) {
 		while(@args < 3) {
 			push @args, "0";
 		}
 	} elsif(@args <= 6) {
 		$asm .= "6";
 		while(@args < 6) {
 			push @args, "0";
 		}
 	} elsif(@args <= 9) {
 		$asm .= "9";
 		while(@args < 9) {
 			push @args, "0";
 		}
 	} else {
 		print STDERR "$ARGV:$.: too many arguments to system call\n";
 	}

 	# System call number.
 	if($sysname eq "") {
 		$sysname = "SYS_$func";
 		$sysname =~ s/([a-z])([A-Z])/${1}_$2/g;	# turn FooBar into Foo_Bar
 		$sysname =~ y/a-z/A-Z/;
 	}

 	# Actual call.
 	my $args = join(', ', @args);
 	my $call = "$asm($sysname, $args)";

 	# Assign return values.
 	my $body = "";
 	my @ret = ("_", "_", "_");
 	my $do_errno = 0;
 	for(my $i=0; $i<@out; $i++) {
 		my $p = $out[$i];
 		my ($name, $type) = parseparam($p);
 		my $reg = "";
 		if($name eq "err" && !$plan9) {
 			$reg = "e1";
 			$ret[2] = $reg;
 			$do_errno = 1;
 		} elsif($name eq "err" && $plan9) {
 			$ret[0] = "r0";
 			$ret[2] = "e1";
 			next;
 		} else {
 			$reg = sprintf("r%d", $i);
 			$ret[$i] = $reg;
 		}
 		if($type eq "bool") {
 			$reg = "$reg != 0";
 		}
 		if($type eq "int64" && $_32bit ne "") {
 			# 64-bit number in r1:r0 or r0:r1.
 			if($i+2 > @out) {
 				print STDERR "$ARGV:$.: not enough registers for int64 return\n";
 			}
 			if($_32bit eq "big-endian") {
 				$reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i, $i+1);
 			} else {
 				$reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i+1, $i);
 			}
 			$ret[$i] = sprintf("r%d", $i);
 			$ret[$i+1] = sprintf("r%d", $i+1);
 		}
 		if($reg ne "e1" || $plan9) {
 			$body .= "\t$name = $type($reg)\n";
 		}
 	}
 	if ($ret[0] eq "_" && $ret[1] eq "_" && $ret[2] eq "_") {
 		$text .= "\t$call\n";
 	} else {
 		$text .= "\t$ret[0], $ret[1], $ret[2] := $call\n";
 	}
 	$text .= $body;

 	if ($plan9 && $ret[2] eq "e1") {
 		$text .= "\tif int32(r0) == -1 {\n";
 		$text .= "\t\terr = e1\n";
 		$text .= "\t}\n";
 	} elsif ($do_errno) {
 		$text .= "\tif e1 != 0 {\n";
 		$text .= "\t\terr = errnoErr(e1)\n";
 		$text .= "\t}\n";
 	}
 	$text .= "\treturn\n";
 	$text .= "}\n\n";
 }

 chomp $text;
 chomp $text;

 if($errors) {
 	exit 1;
 }

 print <<EOF;
 // $cmdline
 // Code generated by the command above; see README.md. DO NOT EDIT.

 // +build $tags

 package unix

 import (
 	"syscall"
 	"unsafe"
 )

 var _ syscall.Errno

 $text
 EOF
 exit 0;
	#!/usr/bin/env perl
	# Copyright 2009 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_darwin.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 errno.

	# A line beginning with //sysnb is like //sys, except that the
	# goroutine will not be suspended during the execution of the system
	# call. This must only be used for system calls which can never
	# block, as otherwise the system call could cause all goroutines to
	# hang.

	use strict;

	my $cmdline = "mksyscall.pl " . join(' ', @ARGV);
	my $errors = 0;
	my $_32bit = "";
	my $plan9 = 0;
	my $openbsd = 0;
	my $netbsd = 0;
	my $dragonfly = 0;
	my $arm = 0; # 64-bit value should use (even, odd)-pair
	my $tags = ""; # build tags

	if($ARGV[0] eq "-b32") {
	$_32bit = "big-endian";
	shift;
	} elsif($ARGV[0] eq "-l32") {
	$_32bit = "little-endian";
	shift;
	}
	if($ARGV[0] eq "-plan9") {
	$plan9 = 1;
	shift;
	}
	if($ARGV[0] eq "-openbsd") {
	$openbsd = 1;
	shift;
	}
	if($ARGV[0] eq "-netbsd") {
	$netbsd = 1;
	shift;
	}
	if($ARGV[0] eq "-dragonfly") {
	$dragonfly = 1;
	shift;
	}
	if($ARGV[0] eq "-arm") {
	$arm = 1;
	shift;
	}
	if($ARGV[0] eq "-tags") {
	shift;
	$tags = $ARGV[0];
	shift;
	}

	if($ARGV[0] =~ /^-/) {
	print STDERR "usage: mksyscall.pl [-b32 \| -l32] [-tags x,y] [file ...]\n";
	exit 1;
	}

	# Check that we are using the new build system if we should
	if($ENV{'GOOS'} eq "linux" && $ENV{'GOARCH'} ne "sparc64") {
	if($ENV{'GOLANG_SYS_BUILD'} ne "docker") {
	print STDERR "In the new build system, mksyscall should not be called directly.\n";
	print STDERR "See README.md\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 $text = "";
	while(<>) {
	chomp;
	s/\s+/ /g;
	s/^\s+//;
	s/\s+$//;
	my $nonblock = /^\/\/sysnb /;
	next if !/^\/\/sys / && !$nonblock;

	# Line must be of the form
	# func Open(path string, mode int, perm int) (fd int, errno error)
	# Split into name, in params, out params.
	if(!/^\/\/sys(nb)? (\w+)\(([^()])\)\s(?:\(([^()]+)\))?\s(?:=\s((?i)SYS_[A-Z0-9_]+))?$/) {
	print STDERR "$ARGV:$.: malformed //sys declaration\n";
	$errors = 1;
	next;
	}
	my ($func, $in, $out, $sysname) = ($2, $3, $4, $5);

	# Split argument lists on comma.
	my @in = parseparamlist($in);
	my @out = parseparamlist($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";

	# Go function header.
	my $out_decl = @out ? sprintf(" (%s)", join(', ', @out)) : "";
	$text .= sprintf "func %s(%s)%s {\n", $func, join(', ', @in), $out_decl;

	# Check if err return available
	my $errvar = "";
	foreach my $p (@out) {
	my ($name, $type) = parseparam($p);
	if($type eq "error") {
	$errvar = $name;
	last;
	}
	}

	# Prepare arguments to Syscall.
	my @args = ();
	my $n = 0;
	foreach my $p (@in) {
	my ($name, $type) = parseparam($p);
	if($type =~ /^\*/) {
	push @args, "uintptr(unsafe.Pointer($name))";
	} elsif($type eq "string" && $errvar ne "") {
	$text .= "\tvar _p$n *byte\n";
	$text .= "\t_p$n, $errvar = BytePtrFromString($name)\n";
	$text .= "\tif $errvar != nil {\n\t\treturn\n\t}\n";
	push @args, "uintptr(unsafe.Pointer(_p$n))";
	$n++;
	} elsif($type eq "string") {
	print STDERR "$ARGV:$.: $func uses string arguments, but has no error return\n";
	$text .= "\tvar _p$n *byte\n";
	$text .= "\t_p$n, _ = BytePtrFromString($name)\n";
	push @args, "uintptr(unsafe.Pointer(_p$n))";
	$n++;
	} elsif($type =~ /^\[\](.*)/) {
	# Convert slice into pointer, length.
	# Have to be careful not to take address of &a[0] if len == 0:
	# pass dummy pointer in that case.
	# Used to pass nil, but some OSes or simulators reject write(fd, nil, 0).
	$text .= "\tvar _p$n unsafe.Pointer\n";
	$text .= "\tif len($name) > 0 {\n\t\t_p$n = unsafe.Pointer(\&${name}[0])\n\t}";
	$text .= " else {\n\t\t_p$n = unsafe.Pointer(&_zero)\n\t}";
	$text .= "\n";
	push @args, "uintptr(_p$n)", "uintptr(len($name))";
	$n++;
	} elsif($type eq "int64" && ($openbsd \|\| $netbsd)) {
	push @args, "0";
	if($_32bit eq "big-endian") {
	push @args, "uintptr($name>>32)", "uintptr($name)";
	} elsif($_32bit eq "little-endian") {
	push @args, "uintptr($name)", "uintptr($name>>32)";
	} else {
	push @args, "uintptr($name)";
	}
	} elsif($type eq "int64" && $dragonfly) {
	if ($func !~ /^extp(read\|write)/i) {
	push @args, "0";
	}
	if($_32bit eq "big-endian") {
	push @args, "uintptr($name>>32)", "uintptr($name)";
	} elsif($_32bit eq "little-endian") {
	push @args, "uintptr($name)", "uintptr($name>>32)";
	} else {
	push @args, "uintptr($name)";
	}
	} elsif($type eq "int64" && $_32bit ne "") {
	if(@args % 2 && $arm) {
	# arm abi specifies 64-bit argument uses
	# (even, odd) pair
	push @args, "0"
	}
	if($_32bit eq "big-endian") {
	push @args, "uintptr($name>>32)", "uintptr($name)";
	} else {
	push @args, "uintptr($name)", "uintptr($name>>32)";
	}
	} else {
	push @args, "uintptr($name)";
	}
	}

	# Determine which form to use; pad args with zeros.
	my $asm = "Syscall";
	if ($nonblock) {
	$asm = "RawSyscall";
	}
	if(@args <= 3) {
	while(@args < 3) {
	push @args, "0";
	}
	} elsif(@args <= 6) {
	$asm .= "6";
	while(@args < 6) {
	push @args, "0";
	}
	} elsif(@args <= 9) {
	$asm .= "9";
	while(@args < 9) {
	push @args, "0";
	}
	} else {
	print STDERR "$ARGV:$.: too many arguments to system call\n";
	}

	# System call number.
	if($sysname eq "") {
	$sysname = "SYS_$func";
	$sysname =~ s/([a-z])([A-Z])/${1}_$2/g; # turn FooBar into Foo_Bar
	$sysname =~ y/a-z/A-Z/;
	}

	# Actual call.
	my $args = join(', ', @args);
	my $call = "$asm($sysname, $args)";

	# Assign return values.
	my $body = "";
	my @ret = ("_", "_", "_");
	my $do_errno = 0;
	for(my $i=0; $i<@out; $i++) {
	my $p = $out[$i];
	my ($name, $type) = parseparam($p);
	my $reg = "";
	if($name eq "err" && !$plan9) {
	$reg = "e1";
	$ret[2] = $reg;
	$do_errno = 1;
	} elsif($name eq "err" && $plan9) {
	$ret[0] = "r0";
	$ret[2] = "e1";
	next;
	} else {
	$reg = sprintf("r%d", $i);
	$ret[$i] = $reg;
	}
	if($type eq "bool") {
	$reg = "$reg != 0";
	}
	if($type eq "int64" && $_32bit ne "") {
	# 64-bit number in r1:r0 or r0:r1.
	if($i+2 > @out) {
	print STDERR "$ARGV:$.: not enough registers for int64 return\n";
	}
	if($_32bit eq "big-endian") {
	$reg = sprintf("int64(r%d)<<32 \| int64(r%d)", $i, $i+1);
	} else {
	$reg = sprintf("int64(r%d)<<32 \| int64(r%d)", $i+1, $i);
	}
	$ret[$i] = sprintf("r%d", $i);
	$ret[$i+1] = sprintf("r%d", $i+1);
	}
	if($reg ne "e1" \|\| $plan9) {
	$body .= "\t$name = $type($reg)\n";
	}
	}
	if ($ret[0] eq "_" && $ret[1] eq "_" && $ret[2] eq "_") {
	$text .= "\t$call\n";
	} else {
	$text .= "\t$ret[0], $ret[1], $ret[2] := $call\n";
	}
	$text .= $body;

	if ($plan9 && $ret[2] eq "e1") {
	$text .= "\tif int32(r0) == -1 {\n";
	$text .= "\t\terr = e1\n";
	$text .= "\t}\n";
	} elsif ($do_errno) {
	$text .= "\tif e1 != 0 {\n";
	$text .= "\t\terr = errnoErr(e1)\n";
	$text .= "\t}\n";
	}
	$text .= "\treturn\n";
	$text .= "}\n\n";
	}

	chomp $text;
	chomp $text;

	if($errors) {
	exit 1;
	}

	print <<EOF;
	// $cmdline
	// Code generated by the command above; see README.md. DO NOT EDIT.

	// +build $tags

	package unix

	import (
	"syscall"
	"unsafe"
	)

	var _ syscall.Errno

	$text
	EOF
	exit 0;