1 #!/usr/bin/env perl |
|
2 # Copyright 2009 The Go Authors. All rights reserved. |
|
3 # Use of this source code is governed by a BSD-style |
|
4 # license that can be found in the LICENSE file. |
|
5 |
|
6 # This program reads a file containing function prototypes |
|
7 # (like syscall_darwin.go) and generates system call bodies. |
|
8 # The prototypes are marked by lines beginning with "//sys" |
|
9 # and read like func declarations if //sys is replaced by func, but: |
|
10 # * The parameter lists must give a name for each argument. |
|
11 # This includes return parameters. |
|
12 # * The parameter lists must give a type for each argument: |
|
13 # the (x, y, z int) shorthand is not allowed. |
|
14 # * If the return parameter is an error number, it must be named errno. |
|
15 |
|
16 # A line beginning with //sysnb is like //sys, except that the |
|
17 # goroutine will not be suspended during the execution of the system |
|
18 # call. This must only be used for system calls which can never |
|
19 # block, as otherwise the system call could cause all goroutines to |
|
20 # hang. |
|
21 |
|
22 use strict; |
|
23 |
|
24 my $cmdline = "mksyscall.pl " . join(' ', @ARGV); |
|
25 my $errors = 0; |
|
26 my $_32bit = ""; |
|
27 my $plan9 = 0; |
|
28 my $openbsd = 0; |
|
29 my $netbsd = 0; |
|
30 my $dragonfly = 0; |
|
31 my $arm = 0; # 64-bit value should use (even, odd)-pair |
|
32 my $tags = ""; # build tags |
|
33 |
|
34 if($ARGV[0] eq "-b32") { |
|
35 $_32bit = "big-endian"; |
|
36 shift; |
|
37 } elsif($ARGV[0] eq "-l32") { |
|
38 $_32bit = "little-endian"; |
|
39 shift; |
|
40 } |
|
41 if($ARGV[0] eq "-plan9") { |
|
42 $plan9 = 1; |
|
43 shift; |
|
44 } |
|
45 if($ARGV[0] eq "-openbsd") { |
|
46 $openbsd = 1; |
|
47 shift; |
|
48 } |
|
49 if($ARGV[0] eq "-netbsd") { |
|
50 $netbsd = 1; |
|
51 shift; |
|
52 } |
|
53 if($ARGV[0] eq "-dragonfly") { |
|
54 $dragonfly = 1; |
|
55 shift; |
|
56 } |
|
57 if($ARGV[0] eq "-arm") { |
|
58 $arm = 1; |
|
59 shift; |
|
60 } |
|
61 if($ARGV[0] eq "-tags") { |
|
62 shift; |
|
63 $tags = $ARGV[0]; |
|
64 shift; |
|
65 } |
|
66 |
|
67 if($ARGV[0] =~ /^-/) { |
|
68 print STDERR "usage: mksyscall.pl [-b32 | -l32] [-tags x,y] [file ...]\n"; |
|
69 exit 1; |
|
70 } |
|
71 |
|
72 # Check that we are using the new build system if we should |
|
73 if($ENV{'GOOS'} eq "linux" && $ENV{'GOARCH'} ne "sparc64") { |
|
74 if($ENV{'GOLANG_SYS_BUILD'} ne "docker") { |
|
75 print STDERR "In the new build system, mksyscall should not be called directly.\n"; |
|
76 print STDERR "See README.md\n"; |
|
77 exit 1; |
|
78 } |
|
79 } |
|
80 |
|
81 |
|
82 sub parseparamlist($) { |
|
83 my ($list) = @_; |
|
84 $list =~ s/^\s*//; |
|
85 $list =~ s/\s*$//; |
|
86 if($list eq "") { |
|
87 return (); |
|
88 } |
|
89 return split(/\s*,\s*/, $list); |
|
90 } |
|
91 |
|
92 sub parseparam($) { |
|
93 my ($p) = @_; |
|
94 if($p !~ /^(\S*) (\S*)$/) { |
|
95 print STDERR "$ARGV:$.: malformed parameter: $p\n"; |
|
96 $errors = 1; |
|
97 return ("xx", "int"); |
|
98 } |
|
99 return ($1, $2); |
|
100 } |
|
101 |
|
102 my $text = ""; |
|
103 while(<>) { |
|
104 chomp; |
|
105 s/\s+/ /g; |
|
106 s/^\s+//; |
|
107 s/\s+$//; |
|
108 my $nonblock = /^\/\/sysnb /; |
|
109 next if !/^\/\/sys / && !$nonblock; |
|
110 |
|
111 # Line must be of the form |
|
112 # func Open(path string, mode int, perm int) (fd int, errno error) |
|
113 # Split into name, in params, out params. |
|
114 if(!/^\/\/sys(nb)? (\w+)\(([^()]*)\)\s*(?:\(([^()]+)\))?\s*(?:=\s*((?i)SYS_[A-Z0-9_]+))?$/) { |
|
115 print STDERR "$ARGV:$.: malformed //sys declaration\n"; |
|
116 $errors = 1; |
|
117 next; |
|
118 } |
|
119 my ($func, $in, $out, $sysname) = ($2, $3, $4, $5); |
|
120 |
|
121 # Split argument lists on comma. |
|
122 my @in = parseparamlist($in); |
|
123 my @out = parseparamlist($out); |
|
124 |
|
125 # Try in vain to keep people from editing this file. |
|
126 # The theory is that they jump into the middle of the file |
|
127 # without reading the header. |
|
128 $text .= "// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n\n"; |
|
129 |
|
130 # Go function header. |
|
131 my $out_decl = @out ? sprintf(" (%s)", join(', ', @out)) : ""; |
|
132 $text .= sprintf "func %s(%s)%s {\n", $func, join(', ', @in), $out_decl; |
|
133 |
|
134 # Check if err return available |
|
135 my $errvar = ""; |
|
136 foreach my $p (@out) { |
|
137 my ($name, $type) = parseparam($p); |
|
138 if($type eq "error") { |
|
139 $errvar = $name; |
|
140 last; |
|
141 } |
|
142 } |
|
143 |
|
144 # Prepare arguments to Syscall. |
|
145 my @args = (); |
|
146 my $n = 0; |
|
147 foreach my $p (@in) { |
|
148 my ($name, $type) = parseparam($p); |
|
149 if($type =~ /^\*/) { |
|
150 push @args, "uintptr(unsafe.Pointer($name))"; |
|
151 } elsif($type eq "string" && $errvar ne "") { |
|
152 $text .= "\tvar _p$n *byte\n"; |
|
153 $text .= "\t_p$n, $errvar = BytePtrFromString($name)\n"; |
|
154 $text .= "\tif $errvar != nil {\n\t\treturn\n\t}\n"; |
|
155 push @args, "uintptr(unsafe.Pointer(_p$n))"; |
|
156 $n++; |
|
157 } elsif($type eq "string") { |
|
158 print STDERR "$ARGV:$.: $func uses string arguments, but has no error return\n"; |
|
159 $text .= "\tvar _p$n *byte\n"; |
|
160 $text .= "\t_p$n, _ = BytePtrFromString($name)\n"; |
|
161 push @args, "uintptr(unsafe.Pointer(_p$n))"; |
|
162 $n++; |
|
163 } elsif($type =~ /^\[\](.*)/) { |
|
164 # Convert slice into pointer, length. |
|
165 # Have to be careful not to take address of &a[0] if len == 0: |
|
166 # pass dummy pointer in that case. |
|
167 # Used to pass nil, but some OSes or simulators reject write(fd, nil, 0). |
|
168 $text .= "\tvar _p$n unsafe.Pointer\n"; |
|
169 $text .= "\tif len($name) > 0 {\n\t\t_p$n = unsafe.Pointer(\&${name}[0])\n\t}"; |
|
170 $text .= " else {\n\t\t_p$n = unsafe.Pointer(&_zero)\n\t}"; |
|
171 $text .= "\n"; |
|
172 push @args, "uintptr(_p$n)", "uintptr(len($name))"; |
|
173 $n++; |
|
174 } elsif($type eq "int64" && ($openbsd || $netbsd)) { |
|
175 push @args, "0"; |
|
176 if($_32bit eq "big-endian") { |
|
177 push @args, "uintptr($name>>32)", "uintptr($name)"; |
|
178 } elsif($_32bit eq "little-endian") { |
|
179 push @args, "uintptr($name)", "uintptr($name>>32)"; |
|
180 } else { |
|
181 push @args, "uintptr($name)"; |
|
182 } |
|
183 } elsif($type eq "int64" && $dragonfly) { |
|
184 if ($func !~ /^extp(read|write)/i) { |
|
185 push @args, "0"; |
|
186 } |
|
187 if($_32bit eq "big-endian") { |
|
188 push @args, "uintptr($name>>32)", "uintptr($name)"; |
|
189 } elsif($_32bit eq "little-endian") { |
|
190 push @args, "uintptr($name)", "uintptr($name>>32)"; |
|
191 } else { |
|
192 push @args, "uintptr($name)"; |
|
193 } |
|
194 } elsif($type eq "int64" && $_32bit ne "") { |
|
195 if(@args % 2 && $arm) { |
|
196 # arm abi specifies 64-bit argument uses |
|
197 # (even, odd) pair |
|
198 push @args, "0" |
|
199 } |
|
200 if($_32bit eq "big-endian") { |
|
201 push @args, "uintptr($name>>32)", "uintptr($name)"; |
|
202 } else { |
|
203 push @args, "uintptr($name)", "uintptr($name>>32)"; |
|
204 } |
|
205 } else { |
|
206 push @args, "uintptr($name)"; |
|
207 } |
|
208 } |
|
209 |
|
210 # Determine which form to use; pad args with zeros. |
|
211 my $asm = "Syscall"; |
|
212 if ($nonblock) { |
|
213 if ($errvar eq "" && $ENV{'GOOS'} eq "linux") { |
|
214 $asm = "RawSyscallNoError"; |
|
215 } else { |
|
216 $asm = "RawSyscall"; |
|
217 } |
|
218 } else { |
|
219 if ($errvar eq "" && $ENV{'GOOS'} eq "linux") { |
|
220 $asm = "SyscallNoError"; |
|
221 } |
|
222 } |
|
223 if(@args <= 3) { |
|
224 while(@args < 3) { |
|
225 push @args, "0"; |
|
226 } |
|
227 } elsif(@args <= 6) { |
|
228 $asm .= "6"; |
|
229 while(@args < 6) { |
|
230 push @args, "0"; |
|
231 } |
|
232 } elsif(@args <= 9) { |
|
233 $asm .= "9"; |
|
234 while(@args < 9) { |
|
235 push @args, "0"; |
|
236 } |
|
237 } else { |
|
238 print STDERR "$ARGV:$.: too many arguments to system call\n"; |
|
239 } |
|
240 |
|
241 # System call number. |
|
242 if($sysname eq "") { |
|
243 $sysname = "SYS_$func"; |
|
244 $sysname =~ s/([a-z])([A-Z])/${1}_$2/g; # turn FooBar into Foo_Bar |
|
245 $sysname =~ y/a-z/A-Z/; |
|
246 } |
|
247 |
|
248 # Actual call. |
|
249 my $args = join(', ', @args); |
|
250 my $call = "$asm($sysname, $args)"; |
|
251 |
|
252 # Assign return values. |
|
253 my $body = ""; |
|
254 my @ret = ("_", "_", "_"); |
|
255 my $do_errno = 0; |
|
256 for(my $i=0; $i<@out; $i++) { |
|
257 my $p = $out[$i]; |
|
258 my ($name, $type) = parseparam($p); |
|
259 my $reg = ""; |
|
260 if($name eq "err" && !$plan9) { |
|
261 $reg = "e1"; |
|
262 $ret[2] = $reg; |
|
263 $do_errno = 1; |
|
264 } elsif($name eq "err" && $plan9) { |
|
265 $ret[0] = "r0"; |
|
266 $ret[2] = "e1"; |
|
267 next; |
|
268 } else { |
|
269 $reg = sprintf("r%d", $i); |
|
270 $ret[$i] = $reg; |
|
271 } |
|
272 if($type eq "bool") { |
|
273 $reg = "$reg != 0"; |
|
274 } |
|
275 if($type eq "int64" && $_32bit ne "") { |
|
276 # 64-bit number in r1:r0 or r0:r1. |
|
277 if($i+2 > @out) { |
|
278 print STDERR "$ARGV:$.: not enough registers for int64 return\n"; |
|
279 } |
|
280 if($_32bit eq "big-endian") { |
|
281 $reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i, $i+1); |
|
282 } else { |
|
283 $reg = sprintf("int64(r%d)<<32 | int64(r%d)", $i+1, $i); |
|
284 } |
|
285 $ret[$i] = sprintf("r%d", $i); |
|
286 $ret[$i+1] = sprintf("r%d", $i+1); |
|
287 } |
|
288 if($reg ne "e1" || $plan9) { |
|
289 $body .= "\t$name = $type($reg)\n"; |
|
290 } |
|
291 } |
|
292 if ($ret[0] eq "_" && $ret[1] eq "_" && $ret[2] eq "_") { |
|
293 $text .= "\t$call\n"; |
|
294 } else { |
|
295 if ($errvar eq "" && $ENV{'GOOS'} eq "linux") { |
|
296 # raw syscall without error on Linux, see golang.org/issue/22924 |
|
297 $text .= "\t$ret[0], $ret[1] := $call\n"; |
|
298 } else { |
|
299 $text .= "\t$ret[0], $ret[1], $ret[2] := $call\n"; |
|
300 } |
|
301 } |
|
302 $text .= $body; |
|
303 |
|
304 if ($plan9 && $ret[2] eq "e1") { |
|
305 $text .= "\tif int32(r0) == -1 {\n"; |
|
306 $text .= "\t\terr = e1\n"; |
|
307 $text .= "\t}\n"; |
|
308 } elsif ($do_errno) { |
|
309 $text .= "\tif e1 != 0 {\n"; |
|
310 $text .= "\t\terr = errnoErr(e1)\n"; |
|
311 $text .= "\t}\n"; |
|
312 } |
|
313 $text .= "\treturn\n"; |
|
314 $text .= "}\n\n"; |
|
315 } |
|
316 |
|
317 chomp $text; |
|
318 chomp $text; |
|
319 |
|
320 if($errors) { |
|
321 exit 1; |
|
322 } |
|
323 |
|
324 print <<EOF; |
|
325 // $cmdline |
|
326 // Code generated by the command above; see README.md. DO NOT EDIT. |
|
327 |
|
328 // +build $tags |
|
329 |
|
330 package unix |
|
331 |
|
332 import ( |
|
333 "syscall" |
|
334 "unsafe" |
|
335 ) |
|
336 |
|
337 var _ syscall.Errno |
|
338 |
|
339 $text |
|
340 EOF |
|
341 exit 0; |
|