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1 | package ExtUtils::Constant; |
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2 | use vars qw (@ISA $VERSION %XS_Constant %XS_TypeSet @EXPORT_OK %EXPORT_TAGS); |
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3 | $VERSION = '0.11'; |
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4 | |
5 | =head1 NAME |
6 | |
7 | ExtUtils::Constant - generate XS code to import C header constants |
8 | |
9 | =head1 SYNOPSIS |
10 | |
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11 | use ExtUtils::Constant qw (WriteConstants); |
12 | WriteConstants( |
13 | NAME => 'Foo', |
14 | NAMES => [qw(FOO BAR BAZ)], |
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15 | ); |
16 | # Generates wrapper code to make the values of the constants FOO BAR BAZ |
17 | # available to perl |
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18 | |
19 | =head1 DESCRIPTION |
20 | |
21 | ExtUtils::Constant facilitates generating C and XS wrapper code to allow |
22 | perl modules to AUTOLOAD constants defined in C library header files. |
23 | It is principally used by the C<h2xs> utility, on which this code is based. |
24 | It doesn't contain the routines to scan header files to extract these |
25 | constants. |
26 | |
27 | =head1 USAGE |
28 | |
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29 | Generally one only needs to call the C<WriteConstants> function, and then |
30 | |
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31 | #include "const-c.inc" |
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32 | |
33 | in the C section of C<Foo.xs> |
34 | |
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35 | INCLUDE const-xs.inc |
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36 | |
37 | in the XS section of C<Foo.xs>. |
38 | |
39 | For greater flexibility use C<constant_types()>, C<C_constant> and |
40 | C<XS_constant>, with which C<WriteConstants> is implemented. |
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41 | |
42 | Currently this module understands the following types. h2xs may only know |
43 | a subset. The sizes of the numeric types are chosen by the C<Configure> |
44 | script at compile time. |
45 | |
46 | =over 4 |
47 | |
48 | =item IV |
49 | |
50 | signed integer, at least 32 bits. |
51 | |
52 | =item UV |
53 | |
54 | unsigned integer, the same size as I<IV> |
55 | |
56 | =item NV |
57 | |
58 | floating point type, probably C<double>, possibly C<long double> |
59 | |
60 | =item PV |
61 | |
62 | NUL terminated string, length will be determined with C<strlen> |
63 | |
64 | =item PVN |
65 | |
66 | A fixed length thing, given as a [pointer, length] pair. If you know the |
67 | length of a string at compile time you may use this instead of I<PV> |
68 | |
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69 | =item SV |
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70 | |
71 | A B<mortal> SV. |
72 | |
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73 | =item YES |
74 | |
75 | Truth. (C<PL_sv_yes>) The value is not needed (and ignored). |
76 | |
77 | =item NO |
78 | |
79 | Defined Falsehood. (C<PL_sv_no>) The value is not needed (and ignored). |
80 | |
81 | =item UNDEF |
82 | |
83 | C<undef>. The value of the macro is not needed. |
84 | |
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85 | =back |
86 | |
87 | =head1 FUNCTIONS |
88 | |
89 | =over 4 |
90 | |
91 | =cut |
92 | |
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93 | if ($] >= 5.006) { |
94 | eval "use warnings; 1" or die $@; |
95 | } |
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96 | use strict; |
97 | use Carp; |
98 | |
99 | use Exporter; |
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100 | use Text::Wrap; |
101 | $Text::Wrap::huge = 'overflow'; |
102 | $Text::Wrap::columns = 80; |
103 | |
104 | @ISA = 'Exporter'; |
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105 | |
106 | %EXPORT_TAGS = ( 'all' => [ qw( |
107 | XS_constant constant_types return_clause memEQ_clause C_stringify |
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108 | C_constant autoload WriteConstants WriteMakefileSnippet |
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109 | ) ] ); |
110 | |
111 | @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } ); |
112 | |
113 | %XS_Constant = ( |
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114 | IV => 'PUSHi(iv)', |
115 | UV => 'PUSHu((UV)iv)', |
116 | NV => 'PUSHn(nv)', |
117 | PV => 'PUSHp(pv, strlen(pv))', |
118 | PVN => 'PUSHp(pv, iv)', |
119 | SV => 'PUSHs(sv)', |
120 | YES => 'PUSHs(&PL_sv_yes)', |
121 | NO => 'PUSHs(&PL_sv_no)', |
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122 | UNDEF => '', # implicit undef |
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123 | ); |
124 | |
125 | %XS_TypeSet = ( |
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126 | IV => '*iv_return =', |
127 | UV => '*iv_return = (IV)', |
128 | NV => '*nv_return =', |
129 | PV => '*pv_return =', |
130 | PVN => ['*pv_return =', '*iv_return = (IV)'], |
131 | SV => '*sv_return = ', |
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132 | YES => undef, |
133 | NO => undef, |
134 | UNDEF => undef, |
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135 | ); |
136 | |
137 | |
138 | =item C_stringify NAME |
139 | |
140 | A function which returns a correctly \ escaped version of the string passed |
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141 | suitable for C's "" or ''. It will also be valid as a perl "" string. |
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142 | |
143 | =cut |
144 | |
145 | # Hopefully make a happy C identifier. |
146 | sub C_stringify { |
147 | local $_ = shift; |
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148 | return unless defined $_; |
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149 | s/\\/\\\\/g; |
150 | s/([\"\'])/\\$1/g; # Grr. fix perl mode. |
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151 | s/\n/\\n/g; # Ensure newlines don't end up in octal |
152 | s/\r/\\r/g; |
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153 | s/\t/\\t/g; |
154 | s/\f/\\f/g; |
155 | s/\a/\\a/g; |
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156 | unless ($] < 5.006) { |
157 | # This will elict a warning on 5.005_03 about [: :] being reserved unless |
158 | # I cheat |
159 | my $cheat = '([[:^print:]])'; |
160 | s/$cheat/sprintf "\\%03o", ord $1/ge; |
161 | } else { |
162 | require POSIX; |
163 | s/([^A-Za-z0-9_])/POSIX::isprint($1) ? $1 : sprintf "\\%03o", ord $1/ge; |
164 | } |
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165 | $_; |
166 | } |
167 | |
168 | =item constant_types |
169 | |
170 | A function returning a single scalar with C<#define> definitions for the |
171 | constants used internally between the generated C and XS functions. |
172 | |
173 | =cut |
174 | |
175 | sub constant_types () { |
176 | my $start = 1; |
177 | my @lines; |
178 | push @lines, "#define PERL_constant_NOTFOUND\t$start\n"; $start++; |
179 | push @lines, "#define PERL_constant_NOTDEF\t$start\n"; $start++; |
180 | foreach (sort keys %XS_Constant) { |
181 | push @lines, "#define PERL_constant_IS$_\t$start\n"; $start++; |
182 | } |
183 | push @lines, << 'EOT'; |
184 | |
185 | #ifndef NVTYPE |
186 | typedef double NV; /* 5.6 and later define NVTYPE, and typedef NV to it. */ |
187 | #endif |
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188 | #ifndef aTHX_ |
189 | #define aTHX_ /* 5.6 or later define this for threading support. */ |
190 | #endif |
191 | #ifndef pTHX_ |
192 | #define pTHX_ /* 5.6 or later define this for threading support. */ |
193 | #endif |
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194 | EOT |
195 | |
196 | return join '', @lines; |
197 | } |
198 | |
199 | =item memEQ_clause NAME, CHECKED_AT, INDENT |
200 | |
201 | A function to return a suitable C C<if> statement to check whether I<NAME> |
202 | is equal to the C variable C<name>. If I<CHECKED_AT> is defined, then it |
203 | is used to avoid C<memEQ> for short names, or to generate a comment to |
204 | highlight the position of the character in the C<switch> statement. |
205 | |
206 | =cut |
207 | |
208 | sub memEQ_clause { |
209 | # if (memEQ(name, "thingy", 6)) { |
210 | # Which could actually be a character comparison or even "" |
211 | my ($name, $checked_at, $indent) = @_; |
212 | $indent = ' ' x ($indent || 4); |
213 | my $len = length $name; |
214 | |
215 | if ($len < 2) { |
216 | return $indent . "{\n" if (defined $checked_at and $checked_at == 0); |
217 | # We didn't switch, drop through to the code for the 2 character string |
218 | $checked_at = 1; |
219 | } |
220 | if ($len < 3 and defined $checked_at) { |
221 | my $check; |
222 | if ($checked_at == 1) { |
223 | $check = 0; |
224 | } elsif ($checked_at == 0) { |
225 | $check = 1; |
226 | } |
227 | if (defined $check) { |
228 | my $char = C_stringify (substr $name, $check, 1); |
229 | return $indent . "if (name[$check] == '$char') {\n"; |
230 | } |
231 | } |
232 | # Could optimise a memEQ on 3 to 2 single character checks here |
233 | $name = C_stringify ($name); |
234 | my $body = $indent . "if (memEQ(name, \"$name\", $len)) {\n"; |
235 | $body .= $indent . "/* ". (' ' x $checked_at) . '^' |
236 | . (' ' x ($len - $checked_at + length $len)) . " */\n" |
237 | if defined $checked_at; |
238 | return $body; |
239 | } |
240 | |
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241 | =item assign INDENT, TYPE, PRE, POST, VALUE... |
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242 | |
243 | A function to return a suitable assignment clause. If I<TYPE> is aggregate |
244 | (eg I<PVN> expects both pointer and length) then there should be multiple |
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245 | I<VALUE>s for the components. I<PRE> and I<POST> if defined give snippets |
246 | of C code to preceed and follow the assignment. I<PRE> will be at the start |
247 | of a block, so variables may be defined in it. |
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248 | |
249 | =cut |
250 | |
251 | # Hmm. value undef to to NOTDEF? value () to do NOTFOUND? |
252 | |
253 | sub assign { |
254 | my $indent = shift; |
255 | my $type = shift; |
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256 | my $pre = shift; |
257 | my $post = shift || ''; |
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258 | my $clause; |
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259 | my $close; |
260 | if ($pre) { |
261 | chomp $pre; |
262 | $clause = $indent . "{\n$pre"; |
263 | $clause .= ";" unless $pre =~ /;$/; |
264 | $clause .= "\n"; |
265 | $close = "$indent}\n"; |
266 | $indent .= " "; |
267 | } |
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268 | die "Can't generate code for type $type" unless exists $XS_TypeSet{$type}; |
269 | my $typeset = $XS_TypeSet{$type}; |
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270 | if (ref $typeset) { |
271 | die "Type $type is aggregate, but only single value given" |
272 | if @_ == 1; |
273 | foreach (0 .. $#$typeset) { |
274 | $clause .= $indent . "$typeset->[$_] $_[$_];\n"; |
275 | } |
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276 | } elsif (defined $typeset) { |
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277 | die "Aggregate value given for type $type" |
278 | if @_ > 1; |
279 | $clause .= $indent . "$typeset $_[0];\n"; |
280 | } |
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281 | chomp $post; |
282 | if (length $post) { |
283 | $clause .= "$post"; |
284 | $clause .= ";" unless $post =~ /;$/; |
285 | $clause .= "\n"; |
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286 | } |
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287 | $clause .= "${indent}return PERL_constant_IS$type;\n"; |
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288 | $clause .= $close if $close; |
6d79cad2 |
289 | return $clause; |
290 | } |
291 | |
5dc6f178 |
292 | =item return_clause |
293 | |
294 | return_clause VALUE, TYPE, INDENT, MACRO, DEFAULT, PRE, POST, PRE, POST |
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295 | |
296 | A function to return a suitable C<#ifdef> clause. I<MACRO> defaults to |
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297 | I<VALUE> when not defined. If I<TYPE> is aggregate (eg I<PVN> expects both |
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298 | pointer and length) then I<VALUE> should be a reference to an array of |
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299 | values in the order expected by the type. C<C_constant> will always call |
300 | this function with I<MACRO> defined, defaulting to the constant's name. |
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301 | I<DEFAULT> if defined is an array reference giving default type and |
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302 | value(s) if the clause generated by I<MACRO> doesn't evaluate to true. |
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303 | The two pairs I<PRE> and I<POST> if defined give C code snippets to proceed |
304 | and follow the value, and the default value. |
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305 | |
306 | =cut |
307 | |
cea00dc5 |
308 | sub return_clause ($$$$$$$$$) { |
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309 | ##ifdef thingy |
310 | # *iv_return = thingy; |
311 | # return PERL_constant_ISIV; |
312 | ##else |
313 | # return PERL_constant_NOTDEF; |
314 | ##endif |
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315 | my ($value, $type, $indent, $macro, $default, $pre, $post, |
316 | $def_pre, $def_post) = @_; |
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317 | $macro = $value unless defined $macro; |
318 | $indent = ' ' x ($indent || 6); |
319 | |
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320 | my $clause; |
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321 | |
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322 | ##ifdef thingy |
323 | if (ref $macro) { |
324 | $clause = $macro->[0]; |
72f7b9a1 |
325 | } elsif ($macro ne "1") { |
6d79cad2 |
326 | $clause = "#ifdef $macro\n"; |
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327 | } |
6d79cad2 |
328 | |
329 | # *iv_return = thingy; |
330 | # return PERL_constant_ISIV; |
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331 | $clause .= assign ($indent, $type, $pre, $post, |
332 | ref $value ? @$value : $value); |
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333 | |
72f7b9a1 |
334 | if (ref $macro or $macro ne "1") { |
335 | ##else |
336 | $clause .= "#else\n"; |
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337 | |
72f7b9a1 |
338 | # return PERL_constant_NOTDEF; |
339 | if (!defined $default) { |
340 | $clause .= "${indent}return PERL_constant_NOTDEF;\n"; |
341 | } else { |
342 | my @default = ref $default ? @$default : $default; |
343 | $type = shift @default; |
344 | $clause .= assign ($indent, $type, $def_pre, $def_post, @default); |
345 | } |
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346 | |
72f7b9a1 |
347 | ##endif |
348 | if (ref $macro) { |
349 | $clause .= $macro->[1]; |
350 | } else { |
351 | $clause .= "#endif\n"; |
352 | } |
6d79cad2 |
353 | } |
354 | return $clause |
af6c647e |
355 | } |
356 | |
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357 | =item switch_clause INDENT, NAMELEN, ITEMHASH, ITEM... |
358 | |
359 | An internal function to generate a suitable C<switch> clause, called by |
360 | C<C_constant> I<ITEM>s are in the hash ref format as given in the description |
361 | of C<C_constant>, and must all have the names of the same length, given by |
362 | I<NAMELEN> (This is not checked). I<ITEMHASH> is a reference to a hash, |
363 | keyed by name, values being the hashrefs in the I<ITEM> list. |
364 | (No parameters are modified, and there can be keys in the I<ITEMHASH> that |
365 | are not in the list of I<ITEM>s without causing problems). |
366 | |
367 | =cut |
368 | |
369 | sub switch_clause { |
370 | my ($indent, $comment, $namelen, $items, @items) = @_; |
371 | $indent = ' ' x ($indent || 2); |
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372 | |
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373 | my @names = sort map {$_->{name}} @items; |
374 | my $leader = $indent . '/* '; |
375 | my $follower = ' ' x length $leader; |
376 | my $body = $indent . "/* Names all of length $namelen. */\n"; |
377 | if ($comment) { |
378 | $body = wrap ($leader, $follower, $comment) . "\n"; |
379 | $leader = $follower; |
380 | } |
381 | $body .= wrap ($leader, $follower, join (" ", @names) . " */") . "\n"; |
382 | # Figure out what to switch on. |
383 | # (RMS, Spread of jump table, Position, Hashref) |
384 | my @best = (1e38, ~0); |
385 | foreach my $i (0 .. ($namelen - 1)) { |
386 | my ($min, $max) = (~0, 0); |
387 | my %spread; |
388 | foreach (@names) { |
389 | my $char = substr $_, $i, 1; |
390 | my $ord = ord $char; |
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391 | $max = $ord if $ord > $max; |
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392 | $min = $ord if $ord < $min; |
393 | push @{$spread{$char}}, $_; |
394 | # warn "$_ $char"; |
395 | } |
396 | # I'm going to pick the character to split on that minimises the root |
397 | # mean square of the number of names in each case. Normally this should |
398 | # be the one with the most keys, but it may pick a 7 where the 8 has |
399 | # one long linear search. I'm not sure if RMS or just sum of squares is |
400 | # actually better. |
401 | # $max and $min are for the tie-breaker if the root mean squares match. |
402 | # Assuming that the compiler may be building a jump table for the |
403 | # switch() then try to minimise the size of that jump table. |
404 | # Finally use < not <= so that if it still ties the earliest part of |
405 | # the string wins. Because if that passes but the memEQ fails, it may |
406 | # only need the start of the string to bin the choice. |
407 | # I think. But I'm micro-optimising. :-) |
408 | my $ss; |
409 | $ss += @$_ * @$_ foreach values %spread; |
410 | my $rms = sqrt ($ss / keys %spread); |
411 | if ($rms < $best[0] || ($rms == $best[0] && ($max - $min) < $best[1])) { |
412 | @best = ($rms, $max - $min, $i, \%spread); |
413 | } |
414 | } |
415 | die "Internal error. Failed to pick a switch point for @names" |
416 | unless defined $best[2]; |
417 | # use Data::Dumper; print Dumper (@best); |
418 | my ($offset, $best) = @best[2,3]; |
419 | $body .= $indent . "/* Offset $offset gives the best switch position. */\n"; |
420 | $body .= $indent . "switch (name[$offset]) {\n"; |
421 | foreach my $char (sort keys %$best) { |
422 | $body .= $indent . "case '" . C_stringify ($char) . "':\n"; |
423 | foreach my $name (sort @{$best->{$char}}) { |
424 | my $thisone = $items->{$name}; |
cea00dc5 |
425 | my ($value, $macro, $default, $pre, $post, $def_pre, $def_post) |
426 | = @$thisone{qw (value macro default pre post def_pre def_post)}; |
8ac27563 |
427 | $value = $name unless defined $value; |
428 | $macro = $name unless defined $macro; |
429 | |
430 | # We have checked this offset. |
431 | $body .= memEQ_clause ($name, $offset, 2 + length $indent); |
432 | $body .= return_clause ($value, $thisone->{type}, 4 + length $indent, |
cea00dc5 |
433 | $macro, $default, $pre, $post, |
434 | $def_pre, $def_post); |
8ac27563 |
435 | $body .= $indent . " }\n"; |
436 | } |
437 | $body .= $indent . " break;\n"; |
438 | } |
439 | $body .= $indent . "}\n"; |
440 | return $body; |
441 | } |
442 | |
af6c647e |
443 | =item params WHAT |
444 | |
445 | An internal function. I<WHAT> should be a hashref of types the constant |
72f7b9a1 |
446 | function will return. I<params> returns a hashref keyed IV NV PV SV to show |
447 | which combination of pointers will be needed in the C argument list. |
af6c647e |
448 | |
449 | =cut |
450 | |
451 | sub params { |
452 | my $what = shift; |
453 | foreach (sort keys %$what) { |
454 | warn "ExtUtils::Constant doesn't know how to handle values of type $_" unless defined $XS_Constant{$_}; |
455 | } |
72f7b9a1 |
456 | my $params = {}; |
457 | $params->{IV} = 1 if $what->{IV} || $what->{UV} || $what->{PVN}; |
458 | $params->{NV} = 1 if $what->{NV}; |
459 | $params->{PV} = 1 if $what->{PV} || $what->{PVN}; |
460 | $params->{SV} = 1 if $what->{SV}; |
461 | return $params; |
af6c647e |
462 | } |
463 | |
a2c454fa |
464 | =item dump_names |
0addb26a |
465 | |
9a7df4f2 |
466 | dump_names DEFAULT_TYPE, TYPES, INDENT, OPTIONS, ITEM... |
6d79cad2 |
467 | |
468 | An internal function to generate the embedded perl code that will regenerate |
9a7df4f2 |
469 | the constant subroutines. I<DEFAULT_TYPE>, I<TYPES> and I<ITEM>s are the |
470 | same as for C_constant. I<INDENT> is treated as number of spaces to indent |
471 | by. I<OPTIONS> is a hashref of options. Currently only C<declare_types> is |
472 | recognised. If the value is true a C<$types> is always declared in the perl |
473 | code generated, if defined and false never declared, and if undefined C<$types> |
474 | is only declared if the values in I<TYPES> as passed in cannot be inferred from |
475 | I<DEFAULT_TYPES> and the I<ITEM>s. |
6d79cad2 |
476 | |
477 | =cut |
478 | |
479 | sub dump_names { |
9a7df4f2 |
480 | my ($default_type, $what, $indent, $options, @items) = @_; |
481 | my $declare_types = $options->{declare_types}; |
482 | $indent = ' ' x ($indent || 0); |
483 | |
484 | my $result; |
485 | my (@simple, @complex, %used_types); |
6d79cad2 |
486 | foreach (@items) { |
9a7df4f2 |
487 | my $type; |
488 | if (ref $_) { |
489 | $type = $_->{type} || $default_type; |
490 | } else { |
491 | $_ = {name=>$_}; |
492 | $type = $default_type; |
493 | } |
494 | $used_types{$type}++; |
6d79cad2 |
495 | if ($type eq $default_type and 0 == ($_->{name} =~ tr/A-Za-z0-9_//c) |
496 | and !defined ($_->{macro}) and !defined ($_->{value}) |
cea00dc5 |
497 | and !defined ($_->{default}) and !defined ($_->{pre}) |
498 | and !defined ($_->{post}) and !defined ($_->{def_pre}) |
499 | and !defined ($_->{def_post})) { |
6d79cad2 |
500 | # It's the default type, and the name consists only of A-Za-z0-9_ |
501 | push @simple, $_->{name}; |
502 | } else { |
503 | push @complex, $_; |
504 | } |
505 | } |
6d79cad2 |
506 | |
9a7df4f2 |
507 | if (!defined $declare_types) { |
508 | # Do they pass in any types we weren't already using? |
509 | foreach (keys %$what) { |
510 | next if $used_types{$_}; |
511 | $declare_types++; # Found one in $what that wasn't used. |
512 | last; # And one is enough to terminate this loop |
513 | } |
514 | } |
515 | if ($declare_types) { |
516 | $result = $indent . 'my $types = {map {($_, 1)} qw(' |
517 | . join (" ", sort keys %$what) . ")};\n"; |
518 | } |
519 | $result .= wrap ($indent . "my \@names = (qw(", |
520 | $indent . " ", join (" ", sort @simple) . ")"); |
6d79cad2 |
521 | if (@complex) { |
522 | foreach my $item (sort {$a->{name} cmp $b->{name}} @complex) { |
523 | my $name = C_stringify $item->{name}; |
9a7df4f2 |
524 | my $line = ",\n$indent {name=>\"$name\""; |
6d79cad2 |
525 | $line .= ", type=>\"$item->{type}\"" if defined $item->{type}; |
cea00dc5 |
526 | foreach my $thing (qw (macro value default pre post def_pre def_post)) { |
527 | my $value = $item->{$thing}; |
528 | if (defined $value) { |
529 | if (ref $value) { |
530 | $line .= ", $thing=>[\"" |
531 | . join ('", "', map {C_stringify $_} @$value) . '"]'; |
532 | } else { |
533 | $line .= ", $thing=>\"" . C_stringify($value) . "\""; |
534 | } |
6d79cad2 |
535 | } |
536 | } |
537 | $line .= "}"; |
538 | # Ensure that the enclosing C comment doesn't end |
539 | # by turning */ into *" . "/ |
540 | $line =~ s!\*\/!\*" . "/!gs; |
3414cef0 |
541 | # gcc -Wall doesn't like finding /* inside a comment |
542 | $line =~ s!\/\*!/" . "\*!gs; |
6d79cad2 |
543 | $result .= $line; |
544 | } |
545 | } |
546 | $result .= ");\n"; |
547 | |
9a7df4f2 |
548 | $result; |
549 | } |
550 | |
551 | |
552 | =item dogfood |
553 | |
554 | dogfood PACKAGE, SUBNAME, DEFAULT_TYPE, TYPES, INDENT, BREAKOUT, ITEM... |
555 | |
556 | An internal function to generate the embedded perl code that will regenerate |
557 | the constant subroutines. Parameters are the same as for C_constant. |
558 | |
559 | =cut |
560 | |
561 | sub dogfood { |
562 | my ($package, $subname, $default_type, $what, $indent, $breakout, @items) |
563 | = @_; |
564 | my $result = <<"EOT"; |
565 | /* When generated this function returned values for the list of names given |
566 | in this section of perl code. Rather than manually editing these functions |
567 | to add or remove constants, which would result in this comment and section |
568 | of code becoming inaccurate, we recommend that you edit this section of |
569 | code, and use it to regenerate a new set of constant functions which you |
570 | then use to replace the originals. |
571 | |
572 | Regenerate these constant functions by feeding this entire source file to |
573 | perl -x |
574 | |
575 | #!$^X -w |
576 | use ExtUtils::Constant qw (constant_types C_constant XS_constant); |
577 | |
578 | EOT |
579 | $result .= dump_names ($default_type, $what, 0, {declare_types=>1}, @items); |
6d79cad2 |
580 | $result .= <<'EOT'; |
581 | |
582 | print constant_types(); # macro defs |
583 | EOT |
584 | $package = C_stringify($package); |
585 | $result .= |
586 | "foreach (C_constant (\"$package\", '$subname', '$default_type', \$types, "; |
587 | # The form of the indent parameter isn't defined. (Yet) |
588 | if (defined $indent) { |
589 | require Data::Dumper; |
590 | $Data::Dumper::Terse=1; |
8ac27563 |
591 | $Data::Dumper::Terse=1; # Not used once. :-) |
6d79cad2 |
592 | chomp ($indent = Data::Dumper::Dumper ($indent)); |
593 | $result .= $indent; |
594 | } else { |
595 | $result .= 'undef'; |
596 | } |
8ac27563 |
597 | $result .= ", $breakout" . ', @names) ) { |
6d79cad2 |
598 | print $_, "\n"; # C constant subs |
599 | } |
600 | print "#### XS Section:\n"; |
601 | print XS_constant ("' . $package . '", $types); |
602 | __END__ |
603 | */ |
604 | |
605 | '; |
a2c454fa |
606 | |
6d79cad2 |
607 | $result; |
608 | } |
609 | |
a2c454fa |
610 | =item C_constant |
0addb26a |
611 | |
8ac27563 |
612 | C_constant PACKAGE, SUBNAME, DEFAULT_TYPE, TYPES, INDENT, BREAKOUT, ITEM... |
af6c647e |
613 | |
614 | A function that returns a B<list> of C subroutine definitions that return |
615 | the value and type of constants when passed the name by the XS wrapper. |
616 | I<ITEM...> gives a list of constant names. Each can either be a string, |
617 | which is taken as a C macro name, or a reference to a hash with the following |
618 | keys |
619 | |
620 | =over 8 |
621 | |
622 | =item name |
623 | |
624 | The name of the constant, as seen by the perl code. |
625 | |
626 | =item type |
627 | |
628 | The type of the constant (I<IV>, I<NV> etc) |
629 | |
630 | =item value |
631 | |
632 | A C expression for the value of the constant, or a list of C expressions if |
633 | the type is aggregate. This defaults to the I<name> if not given. |
634 | |
635 | =item macro |
636 | |
637 | The C pre-processor macro to use in the C<#ifdef>. This defaults to the |
6d79cad2 |
638 | I<name>, and is mainly used if I<value> is an C<enum>. If a reference an |
639 | array is passed then the first element is used in place of the C<#ifdef> |
640 | line, and the second element in place of the C<#endif>. This allows |
641 | pre-processor constructions such as |
642 | |
643 | #if defined (foo) |
644 | #if !defined (bar) |
645 | ... |
646 | #endif |
647 | #endif |
648 | |
649 | to be used to determine if a constant is to be defined. |
650 | |
72f7b9a1 |
651 | A "macro" 1 signals that the constant is always defined, so the C<#if>/C<#endif> |
652 | test is omitted. |
653 | |
6d79cad2 |
654 | =item default |
655 | |
656 | Default value to use (instead of C<croak>ing with "your vendor has not |
657 | defined...") to return if the macro isn't defined. Specify a reference to |
658 | an array with type followed by value(s). |
af6c647e |
659 | |
cea00dc5 |
660 | =item pre |
661 | |
662 | C code to use before the assignment of the value of the constant. This allows |
663 | you to use temporary variables to extract a value from part of a C<struct> |
664 | and return this as I<value>. This C code is places at the start of a block, |
665 | so you can declare variables in it. |
666 | |
667 | =item post |
668 | |
669 | C code to place between the assignment of value (to a temporary) and the |
670 | return from the function. This allows you to clear up anything in I<pre>. |
671 | Rarely needed. |
672 | |
673 | =item def_pre |
674 | =item def_post |
675 | |
676 | Equivalents of I<pre> and I<post> for the default value. |
677 | |
af6c647e |
678 | =back |
679 | |
6d79cad2 |
680 | I<PACKAGE> is the name of the package, and is only used in comments inside the |
681 | generated C code. |
682 | |
683 | The next 5 arguments can safely be given as C<undef>, and are mainly used |
af6c647e |
684 | for recursion. I<SUBNAME> defaults to C<constant> if undefined. |
685 | |
686 | I<DEFAULT_TYPE> is the type returned by C<ITEM>s that don't specify their |
687 | type. In turn it defaults to I<IV>. I<TYPES> should be given either as a comma |
688 | separated list of types that the C subroutine C<constant> will generate or as |
689 | a reference to a hash. I<DEFAULT_TYPE> will be added to the list if not |
690 | present, as will any types given in the list of I<ITEM>s. The resultant list |
691 | should be the same list of types that C<XS_constant> is given. [Otherwise |
692 | C<XS_constant> and C<C_constant> may differ in the number of parameters to the |
693 | constant function. I<INDENT> is currently unused and ignored. In future it may |
694 | be used to pass in information used to change the C indentation style used.] |
695 | The best way to maintain consistency is to pass in a hash reference and let |
696 | this function update it. |
697 | |
8ac27563 |
698 | I<BREAKOUT> governs when child functions of I<SUBNAME> are generated. If there |
699 | are I<BREAKOUT> or more I<ITEM>s with the same length of name, then the code |
700 | to switch between them is placed into a function named I<SUBNAME>_I<LEN>, for |
701 | example C<constant_5> for names 5 characters long. The default I<BREAKOUT> is |
702 | 3. A single C<ITEM> is always inlined. |
af6c647e |
703 | |
704 | =cut |
705 | |
8ac27563 |
706 | # The parameter now BREAKOUT was previously documented as: |
707 | # |
708 | # I<NAMELEN> if defined signals that all the I<name>s of the I<ITEM>s are of |
709 | # this length, and that the constant name passed in by perl is checked and |
710 | # also of this length. It is used during recursion, and should be C<undef> |
711 | # unless the caller has checked all the lengths during code generation, and |
712 | # the generated subroutine is only to be called with a name of this length. |
713 | # |
714 | # As you can see it now performs this function during recursion by being a |
715 | # scalar reference. |
716 | |
af6c647e |
717 | sub C_constant { |
8ac27563 |
718 | my ($package, $subname, $default_type, $what, $indent, $breakout, @items) |
719 | = @_; |
6d79cad2 |
720 | $package ||= 'Foo'; |
af6c647e |
721 | $subname ||= 'constant'; |
722 | # I'm not using this. But a hashref could be used for full formatting without |
723 | # breaking this API |
6d79cad2 |
724 | # $indent ||= 0; |
72f7b9a1 |
725 | |
726 | my ($namelen, $items); |
727 | if (ref $breakout) { |
728 | # We are called recursively. We trust @items to be normalised, $what to |
729 | # be a hashref, and pinch %$items from our parent to save recalculation. |
730 | ($namelen, $items) = @$breakout; |
731 | } else { |
732 | $breakout ||= 3; |
733 | $default_type ||= 'IV'; |
734 | if (!ref $what) { |
735 | # Convert line of the form IV,UV,NV to hash |
736 | $what = {map {$_ => 1} split /,\s*/, ($what || '')}; |
737 | # Figure out what types we're dealing with, and assign all unknowns to the |
738 | # default type |
af6c647e |
739 | } |
72f7b9a1 |
740 | foreach (@items) { |
741 | my $name; |
742 | if (ref $_) { |
743 | my $orig = $_; |
744 | # Make a copy which is a normalised version of the ref passed in. |
745 | $name = $_->{name}; |
746 | my ($type, $macro, $value) = @$_{qw (type macro value)}; |
747 | $type ||= $default_type; |
748 | $what->{$type} = 1; |
749 | $_ = {name=>$name, type=>$type}; |
750 | |
751 | undef $macro if defined $macro and $macro eq $name; |
752 | $_->{macro} = $macro if defined $macro; |
753 | undef $value if defined $value and $value eq $name; |
754 | $_->{value} = $value if defined $value; |
755 | foreach my $key (qw(default pre post def_pre def_post)) { |
756 | my $value = $orig->{$key}; |
757 | $_->{$key} = $value if defined $value; |
758 | # warn "$key $value"; |
759 | } |
760 | } else { |
761 | $name = $_; |
762 | $_ = {name=>$_, type=>$default_type}; |
763 | $what->{$default_type} = 1; |
764 | } |
765 | warn "ExtUtils::Constant doesn't know how to handle values of type $_ used in macro $name" unless defined $XS_Constant{$_->{type}}; |
766 | if (exists $items->{$name}) { |
767 | die "Multiple definitions for macro $name"; |
768 | } |
769 | $items->{$name} = $_; |
af6c647e |
770 | } |
af6c647e |
771 | } |
72f7b9a1 |
772 | my $params = params ($what); |
af6c647e |
773 | |
a2c454fa |
774 | my ($body, @subs) = "static int\n$subname (pTHX_ const char *name"; |
af6c647e |
775 | $body .= ", STRLEN len" unless defined $namelen; |
72f7b9a1 |
776 | $body .= ", IV *iv_return" if $params->{IV}; |
777 | $body .= ", NV *nv_return" if $params->{NV}; |
778 | $body .= ", const char **pv_return" if $params->{PV}; |
779 | $body .= ", SV **sv_return" if $params->{SV}; |
af6c647e |
780 | $body .= ") {\n"; |
781 | |
6d79cad2 |
782 | if (defined $namelen) { |
783 | # We are a child subroutine. Print the simple description |
8ac27563 |
784 | my $comment = 'When generated this function returned values for the list' |
785 | . ' of names given here. However, subsequent manual editing may have' |
786 | . ' added or removed some.'; |
72f7b9a1 |
787 | $body .= switch_clause (2, $comment, $namelen, $items, @items); |
af6c647e |
788 | } else { |
789 | # We are the top level. |
790 | $body .= " /* Initially switch on the length of the name. */\n"; |
9a7df4f2 |
791 | $body .= dogfood ($package, $subname, $default_type, $what, $indent, |
792 | $breakout, @items); |
af6c647e |
793 | $body .= " switch (len) {\n"; |
794 | # Need to group names of the same length |
795 | my @by_length; |
796 | foreach (@items) { |
797 | push @{$by_length[length $_->{name}]}, $_; |
798 | } |
799 | foreach my $i (0 .. $#by_length) { |
800 | next unless $by_length[$i]; # None of this length |
801 | $body .= " case $i:\n"; |
802 | if (@{$by_length[$i]} == 1) { |
803 | my $thisone = $by_length[$i]->[0]; |
cea00dc5 |
804 | my ($name, $value, $macro, $default, $pre, $post, $def_pre, $def_post) |
805 | = @$thisone{qw (name value macro default pre post def_pre def_post)}; |
af6c647e |
806 | $value = $name unless defined $value; |
807 | $macro = $name unless defined $macro; |
808 | |
809 | $body .= memEQ_clause ($name); |
6d79cad2 |
810 | $body .= return_clause ($value, $thisone->{type}, undef, $macro, |
cea00dc5 |
811 | $default, $pre, $post, $def_pre, $def_post); |
af6c647e |
812 | $body .= " }\n"; |
8ac27563 |
813 | } elsif (@{$by_length[$i]} < $breakout) { |
72f7b9a1 |
814 | $body .= switch_clause (4, '', $i, $items, @{$by_length[$i]}); |
af6c647e |
815 | } else { |
72f7b9a1 |
816 | # Only use the minimal set of parameters actually needed by the types |
817 | # of the names of this length. |
818 | my $what = {}; |
819 | foreach (@{$by_length[$i]}) { |
820 | $what->{$_->{type}} = 1; |
821 | } |
822 | $params = params ($what); |
823 | push @subs, C_constant ($package, "${subname}_$i", $default_type, $what, |
824 | $indent, [$i, $items], @{$by_length[$i]}); |
a2c454fa |
825 | $body .= " return ${subname}_$i (aTHX_ name"; |
72f7b9a1 |
826 | $body .= ", iv_return" if $params->{IV}; |
827 | $body .= ", nv_return" if $params->{NV}; |
828 | $body .= ", pv_return" if $params->{PV}; |
829 | $body .= ", sv_return" if $params->{SV}; |
af6c647e |
830 | $body .= ");\n"; |
831 | } |
832 | $body .= " break;\n"; |
833 | } |
834 | $body .= " }\n"; |
835 | } |
836 | $body .= " return PERL_constant_NOTFOUND;\n}\n"; |
837 | return (@subs, $body); |
838 | } |
839 | |
840 | =item XS_constant PACKAGE, TYPES, SUBNAME, C_SUBNAME |
841 | |
842 | A function to generate the XS code to implement the perl subroutine |
843 | I<PACKAGE>::constant used by I<PACKAGE>::AUTOLOAD to load constants. |
844 | This XS code is a wrapper around a C subroutine usually generated by |
845 | C<C_constant>, and usually named C<constant>. |
846 | |
847 | I<TYPES> should be given either as a comma separated list of types that the |
848 | C subroutine C<constant> will generate or as a reference to a hash. It should |
849 | be the same list of types as C<C_constant> was given. |
850 | [Otherwise C<XS_constant> and C<C_constant> may have different ideas about |
851 | the number of parameters passed to the C function C<constant>] |
852 | |
853 | You can call the perl visible subroutine something other than C<constant> if |
d1be9408 |
854 | you give the parameter I<SUBNAME>. The C subroutine it calls defaults to |
af6c647e |
855 | the name of the perl visible subroutine, unless you give the parameter |
856 | I<C_SUBNAME>. |
857 | |
858 | =cut |
859 | |
860 | sub XS_constant { |
861 | my $package = shift; |
862 | my $what = shift; |
863 | my $subname = shift; |
864 | my $C_subname = shift; |
865 | $subname ||= 'constant'; |
866 | $C_subname ||= $subname; |
867 | |
868 | if (!ref $what) { |
869 | # Convert line of the form IV,UV,NV to hash |
870 | $what = {map {$_ => 1} split /,\s*/, ($what)}; |
871 | } |
72f7b9a1 |
872 | my $params = params ($what); |
af6c647e |
873 | my $type; |
874 | |
875 | my $xs = <<"EOT"; |
876 | void |
877 | $subname(sv) |
878 | PREINIT: |
879 | #ifdef dXSTARG |
880 | dXSTARG; /* Faster if we have it. */ |
881 | #else |
882 | dTARGET; |
883 | #endif |
884 | STRLEN len; |
885 | int type; |
886 | EOT |
887 | |
72f7b9a1 |
888 | if ($params->{IV}) { |
af6c647e |
889 | $xs .= " IV iv;\n"; |
890 | } else { |
891 | $xs .= " /* IV\t\tiv;\tUncomment this if you need to return IVs */\n"; |
892 | } |
72f7b9a1 |
893 | if ($params->{NV}) { |
af6c647e |
894 | $xs .= " NV nv;\n"; |
895 | } else { |
896 | $xs .= " /* NV\t\tnv;\tUncomment this if you need to return NVs */\n"; |
897 | } |
72f7b9a1 |
898 | if ($params->{PV}) { |
af6c647e |
899 | $xs .= " const char *pv;\n"; |
900 | } else { |
901 | $xs .= |
902 | " /* const char\t*pv;\tUncomment this if you need to return PVs */\n"; |
903 | } |
904 | |
905 | $xs .= << 'EOT'; |
906 | INPUT: |
907 | SV * sv; |
908 | const char * s = SvPV(sv, len); |
909 | PPCODE: |
910 | EOT |
911 | |
72f7b9a1 |
912 | if ($params->{IV} xor $params->{NV}) { |
af6c647e |
913 | $xs .= << "EOT"; |
a2c454fa |
914 | /* Change this to $C_subname(aTHX_ s, len, &iv, &nv); |
af6c647e |
915 | if you need to return both NVs and IVs */ |
916 | EOT |
917 | } |
a2c454fa |
918 | $xs .= " type = $C_subname(aTHX_ s, len"; |
72f7b9a1 |
919 | $xs .= ', &iv' if $params->{IV}; |
920 | $xs .= ', &nv' if $params->{NV}; |
921 | $xs .= ', &pv' if $params->{PV}; |
922 | $xs .= ', &sv' if $params->{SV}; |
af6c647e |
923 | $xs .= ");\n"; |
924 | |
925 | $xs .= << "EOT"; |
926 | /* Return 1 or 2 items. First is error message, or undef if no error. |
927 | Second, if present, is found value */ |
928 | switch (type) { |
929 | case PERL_constant_NOTFOUND: |
930 | sv = sv_2mortal(newSVpvf("%s is not a valid $package macro", s)); |
6d79cad2 |
931 | PUSHs(sv); |
af6c647e |
932 | break; |
933 | case PERL_constant_NOTDEF: |
934 | sv = sv_2mortal(newSVpvf( |
8ac27563 |
935 | "Your vendor has not defined $package macro %s, used", s)); |
6d79cad2 |
936 | PUSHs(sv); |
af6c647e |
937 | break; |
938 | EOT |
939 | |
940 | foreach $type (sort keys %XS_Constant) { |
941 | $xs .= "\t/* Uncomment this if you need to return ${type}s\n" |
942 | unless $what->{$type}; |
8ac27563 |
943 | $xs .= " case PERL_constant_IS$type:\n"; |
944 | if (length $XS_Constant{$type}) { |
945 | $xs .= << "EOT"; |
af6c647e |
946 | EXTEND(SP, 1); |
947 | PUSHs(&PL_sv_undef); |
948 | $XS_Constant{$type}; |
af6c647e |
949 | EOT |
8ac27563 |
950 | } else { |
951 | # Do nothing. return (), which will be correctly interpreted as |
952 | # (undef, undef) |
953 | } |
954 | $xs .= " break;\n"; |
af6c647e |
955 | unless ($what->{$type}) { |
956 | chop $xs; # Yes, another need for chop not chomp. |
957 | $xs .= " */\n"; |
958 | } |
959 | } |
960 | $xs .= << "EOT"; |
961 | default: |
962 | sv = sv_2mortal(newSVpvf( |
8ac27563 |
963 | "Unexpected return type %d while processing $package macro %s, used", |
af6c647e |
964 | type, s)); |
6d79cad2 |
965 | PUSHs(sv); |
af6c647e |
966 | } |
967 | EOT |
968 | |
969 | return $xs; |
970 | } |
971 | |
972 | |
6d79cad2 |
973 | =item autoload PACKAGE, VERSION, AUTOLOADER |
af6c647e |
974 | |
975 | A function to generate the AUTOLOAD subroutine for the module I<PACKAGE> |
976 | I<VERSION> is the perl version the code should be backwards compatible with. |
6d79cad2 |
977 | It defaults to the version of perl running the subroutine. If I<AUTOLOADER> |
978 | is true, the AUTOLOAD subroutine falls back on AutoLoader::AUTOLOAD for all |
979 | names that the constant() routine doesn't recognise. |
af6c647e |
980 | |
981 | =cut |
982 | |
6d79cad2 |
983 | # ' # Grr. syntax highlighters that don't grok pod. |
984 | |
af6c647e |
985 | sub autoload { |
6d79cad2 |
986 | my ($module, $compat_version, $autoloader) = @_; |
af6c647e |
987 | $compat_version ||= $]; |
988 | croak "Can't maintain compatibility back as far as version $compat_version" |
989 | if $compat_version < 5; |
6d79cad2 |
990 | my $func = "sub AUTOLOAD {\n" |
991 | . " # This AUTOLOAD is used to 'autoload' constants from the constant()\n" |
992 | . " # XS function."; |
993 | $func .= " If a constant is not found then control is passed\n" |
994 | . " # to the AUTOLOAD in AutoLoader." if $autoloader; |
995 | |
996 | |
997 | $func .= "\n\n" |
998 | . " my \$constname;\n"; |
a2c454fa |
999 | $func .= |
6d79cad2 |
1000 | " our \$AUTOLOAD;\n" if ($compat_version >= 5.006); |
1001 | |
1002 | $func .= <<"EOT"; |
af6c647e |
1003 | (\$constname = \$AUTOLOAD) =~ s/.*:://; |
1004 | croak "&${module}::constant not defined" if \$constname eq 'constant'; |
1005 | my (\$error, \$val) = constant(\$constname); |
6d79cad2 |
1006 | EOT |
1007 | |
1008 | if ($autoloader) { |
1009 | $func .= <<'EOT'; |
1010 | if ($error) { |
1011 | if ($error =~ /is not a valid/) { |
1012 | $AutoLoader::AUTOLOAD = $AUTOLOAD; |
af6c647e |
1013 | goto &AutoLoader::AUTOLOAD; |
1014 | } else { |
6d79cad2 |
1015 | croak $error; |
af6c647e |
1016 | } |
1017 | } |
6d79cad2 |
1018 | EOT |
1019 | } else { |
1020 | $func .= |
1021 | " if (\$error) { croak \$error; }\n"; |
1022 | } |
1023 | |
1024 | $func .= <<'END'; |
af6c647e |
1025 | { |
1026 | no strict 'refs'; |
1027 | # Fixed between 5.005_53 and 5.005_61 |
6d79cad2 |
1028 | #XXX if ($] >= 5.00561) { |
1029 | #XXX *$AUTOLOAD = sub () { $val }; |
af6c647e |
1030 | #XXX } |
1031 | #XXX else { |
6d79cad2 |
1032 | *$AUTOLOAD = sub { $val }; |
af6c647e |
1033 | #XXX } |
1034 | } |
6d79cad2 |
1035 | goto &$AUTOLOAD; |
af6c647e |
1036 | } |
1037 | |
1038 | END |
1039 | |
6d79cad2 |
1040 | return $func; |
af6c647e |
1041 | } |
0552bf3a |
1042 | |
1043 | |
9a7df4f2 |
1044 | =item WriteMakefileSnippet |
1045 | |
1046 | WriteMakefileSnippet ATTRIBUTE =E<gt> VALUE [, ...] |
1047 | |
d1be9408 |
1048 | A function to generate perl code for Makefile.PL that will regenerate |
9a7df4f2 |
1049 | the constant subroutines. Parameters are named as passed to C<WriteConstants>, |
1050 | with the addition of C<INDENT> to specify the number of leading spaces |
1051 | (default 2). |
1052 | |
1053 | Currently only C<INDENT>, C<NAME>, C<DEFAULT_TYPE>, C<NAMES>, C<C_FILE> and |
1054 | C<XS_FILE> are recognised. |
1055 | |
1056 | =cut |
1057 | |
1058 | sub WriteMakefileSnippet { |
1059 | my %args = @_; |
1060 | my $indent = $args{INDENT} || 2; |
1061 | |
1062 | my $result = <<"EOT"; |
1063 | ExtUtils::Constant::WriteConstants( |
1064 | NAME => '$args{NAME}', |
1065 | NAMES => \\\@names, |
1066 | DEFAULT_TYPE => '$args{DEFAULT_TYPE}', |
1067 | EOT |
1068 | foreach (qw (C_FILE XS_FILE)) { |
1069 | next unless exists $args{$_}; |
1070 | $result .= sprintf " %-12s => '%s',\n", |
1071 | $_, $args{$_}; |
1072 | } |
1073 | $result .= <<'EOT'; |
1074 | ); |
1075 | EOT |
1076 | |
1077 | $result =~ s/^/' 'x$indent/gem; |
1078 | return dump_names ($args{DEFAULT_TYPE}, undef, $indent, undef, |
1079 | @{$args{NAMES}}) |
1080 | . $result; |
1081 | } |
1082 | |
0552bf3a |
1083 | =item WriteConstants ATTRIBUTE =E<gt> VALUE [, ...] |
1084 | |
1085 | Writes a file of C code and a file of XS code which you should C<#include> |
1086 | and C<INCLUDE> in the C and XS sections respectively of your module's XS |
1087 | code. You probaby want to do this in your C<Makefile.PL>, so that you can |
1088 | easily edit the list of constants without touching the rest of your module. |
1089 | The attributes supported are |
1090 | |
1091 | =over 4 |
1092 | |
1093 | =item NAME |
1094 | |
1095 | Name of the module. This must be specified |
1096 | |
1097 | =item DEFAULT_TYPE |
1098 | |
1099 | The default type for the constants. If not specified C<IV> is assumed. |
1100 | |
1101 | =item BREAKOUT_AT |
1102 | |
1103 | The names of the constants are grouped by length. Generate child subroutines |
1104 | for each group with this number or more names in. |
1105 | |
1106 | =item NAMES |
1107 | |
1108 | An array of constants' names, either scalars containing names, or hashrefs |
1109 | as detailed in L<"C_constant">. |
1110 | |
1111 | =item C_FILE |
1112 | |
1113 | The name of the file to write containing the C code. The default is |
1cb0fb50 |
1114 | C<const-c.inc>. The C<-> in the name ensures that the file can't be |
1115 | mistaken for anything related to a legitimate perl package name, and |
1116 | not naming the file C<.c> avoids having to override Makefile.PL's |
1117 | C<.xs> to C<.c> rules. |
0552bf3a |
1118 | |
1119 | =item XS_FILE |
1120 | |
1121 | The name of the file to write containing the XS code. The default is |
1cb0fb50 |
1122 | C<const-xs.inc>. |
0552bf3a |
1123 | |
1124 | =item SUBNAME |
1125 | |
1126 | The perl visible name of the XS subroutine generated which will return the |
9a7df4f2 |
1127 | constants. The default is C<constant>. |
0552bf3a |
1128 | |
1129 | =item C_SUBNAME |
1130 | |
1131 | The name of the C subroutine generated which will return the constants. |
1132 | The default is I<SUBNAME>. Child subroutines have C<_> and the name |
1133 | length appended, so constants with 10 character names would be in |
1134 | C<constant_10> with the default I<XS_SUBNAME>. |
1135 | |
1136 | =back |
1137 | |
1138 | =cut |
1139 | |
1140 | sub WriteConstants { |
1141 | my %ARGS = |
1142 | ( # defaults |
1cb0fb50 |
1143 | C_FILE => 'const-c.inc', |
1144 | XS_FILE => 'const-xs.inc', |
0552bf3a |
1145 | SUBNAME => 'constant', |
1146 | DEFAULT_TYPE => 'IV', |
1147 | @_); |
1148 | |
1149 | $ARGS{C_SUBNAME} ||= $ARGS{SUBNAME}; # No-one sane will have C_SUBNAME eq '0' |
1150 | |
1151 | croak "Module name not specified" unless length $ARGS{NAME}; |
1152 | |
1153 | open my $c_fh, ">$ARGS{C_FILE}" or die "Can't open $ARGS{C_FILE}: $!"; |
1154 | open my $xs_fh, ">$ARGS{XS_FILE}" or die "Can't open $ARGS{XS_FILE}: $!"; |
1155 | |
1156 | # As this subroutine is intended to make code that isn't edited, there's no |
1157 | # need for the user to specify any types that aren't found in the list of |
1158 | # names. |
1159 | my $types = {}; |
1160 | |
1161 | print $c_fh constant_types(); # macro defs |
1162 | print $c_fh "\n"; |
1163 | |
1164 | # indent is still undef. Until anyone implents indent style rules with it. |
1165 | foreach (C_constant ($ARGS{NAME}, $ARGS{C_SUBNAME}, $ARGS{DEFAULT_TYPE}, |
1166 | $types, undef, $ARGS{BREAKOUT_AT}, @{$ARGS{NAMES}})) { |
1167 | print $c_fh $_, "\n"; # C constant subs |
1168 | } |
1169 | print $xs_fh XS_constant ($ARGS{NAME}, $types, $ARGS{XS_SUBNAME}, |
1170 | $ARGS{C_SUBNAME}); |
1171 | |
1172 | close $c_fh or warn "Error closing $ARGS{C_FILE}: $!"; |
1173 | close $xs_fh or warn "Error closing $ARGS{XS_FILE}: $!"; |
1174 | } |
1175 | |
af6c647e |
1176 | 1; |
1177 | __END__ |
1178 | |
1179 | =back |
1180 | |
1181 | =head1 AUTHOR |
1182 | |
1183 | Nicholas Clark <nick@ccl4.org> based on the code in C<h2xs> by Larry Wall and |
1184 | others |
1185 | |
1186 | =cut |