Commit | Line | Data |
---|---|---|
599cee73 | 1 | #!/usr/bin/perl |
c4a853d1 | 2 | # |
6294c161 DM |
3 | # Regenerate (overwriting only if changed): |
4 | # | |
5 | # lib/warnings.pm | |
6 | # warnings.h | |
7 | # | |
0144c000 | 8 | # from information hardcoded into this script (the $WARNING_TREE hash), plus the |
d2ec25a5 | 9 | # template for warnings.pm in the DATA section. |
6294c161 | 10 | # |
91efc02c KW |
11 | # When changing the number of warnings, t/op/caller.t should change to |
12 | # correspond with the value of $BYTES in lib/warnings.pm | |
8457b38f | 13 | # |
0144c000 | 14 | # With an argument of 'tree', just dump the contents of $WARNING_TREE and exits. |
6294c161 DM |
15 | # Also accepts the standard regen_lib -q and -v args. |
16 | # | |
17 | # This script is normally invoked from regen.pl. | |
599cee73 | 18 | |
f1cf82e7 | 19 | $VERSION = '1.67'; |
b75c8c73 | 20 | |
73f0cc2d | 21 | BEGIN { |
3d7c117d | 22 | require './regen/regen_lib.pl'; |
b6b9a099 | 23 | push @INC, './lib'; |
73f0cc2d | 24 | } |
599cee73 PM |
25 | use strict ; |
26 | ||
27 | sub DEFAULT_ON () { 1 } | |
28 | sub DEFAULT_OFF () { 2 } | |
29 | ||
b4353f19 DM |
30 | |
31 | # Define the hierarchy of warnings. | |
32 | # | |
33 | # Each level in the tree is a hash which lists the names of all the | |
34 | # children below that level. Each child is an array consisting of the | |
35 | # version when that warnings category was introduced and, if a terminal | |
36 | # category, whether that warning is on by default; otherwise a ref to | |
37 | # another hash of children. | |
38 | # | |
39 | # Note that the version numbers are currently only used to sort and to | |
40 | # generate code comments in the output files. | |
41 | # | |
42 | # Note that warning names aren't hierarchical; by having 'pipe' as a child | |
43 | # of 'io', a warnings category called 'io::pipe' is NOT automatically | |
44 | # created. But the warnings category 'io' WILL include all the mask bits | |
45 | # necessary to turn on 'pipe', 'unopened' etc. | |
46 | ||
0144c000 | 47 | our $WARNING_TREE = { |
3c3f8cd6 AB |
48 | 'all' => [ 5.008, { |
49 | 'io' => [ 5.008, { | |
50 | 'pipe' => [ 5.008, DEFAULT_OFF], | |
51 | 'unopened' => [ 5.008, DEFAULT_OFF], | |
52 | 'closed' => [ 5.008, DEFAULT_OFF], | |
53 | 'newline' => [ 5.008, DEFAULT_OFF], | |
54 | 'exec' => [ 5.008, DEFAULT_OFF], | |
55 | 'layer' => [ 5.008, DEFAULT_OFF], | |
56 | 'syscalls' => [ 5.019, DEFAULT_OFF], | |
57 | }], | |
58 | 'syntax' => [ 5.008, { | |
59 | 'ambiguous' => [ 5.008, DEFAULT_OFF], | |
60 | 'semicolon' => [ 5.008, DEFAULT_OFF], | |
61 | 'precedence' => [ 5.008, DEFAULT_OFF], | |
62 | 'bareword' => [ 5.008, DEFAULT_OFF], | |
63 | 'reserved' => [ 5.008, DEFAULT_OFF], | |
64 | 'digit' => [ 5.008, DEFAULT_OFF], | |
65 | 'parenthesis' => [ 5.008, DEFAULT_OFF], | |
66 | 'printf' => [ 5.008, DEFAULT_OFF], | |
67 | 'prototype' => [ 5.008, DEFAULT_OFF], | |
68 | 'qw' => [ 5.008, DEFAULT_OFF], | |
69 | 'illegalproto' => [ 5.011, DEFAULT_OFF], | |
70 | }], | |
71 | 'severe' => [ 5.008, { | |
72 | 'inplace' => [ 5.008, DEFAULT_ON], | |
73 | 'internal' => [ 5.008, DEFAULT_OFF], | |
74 | 'debugging' => [ 5.008, DEFAULT_ON], | |
75 | 'malloc' => [ 5.008, DEFAULT_ON], | |
76 | }], | |
d81b4f93 | 77 | 'deprecated' => [ 5.008, DEFAULT_ON, { |
2d8fceed | 78 | 'deprecated::goto_construct' => [ 5.011003, DEFAULT_ON], |
2be0f9ab YO |
79 | 'deprecated::unicode_property_name' => [ 5.011003, DEFAULT_ON], |
80 | 'deprecated::dot_in_inc' => [ 5.025011, DEFAULT_ON], | |
b689ed93 | 81 | 'deprecated::version_downgrade' => [ 5.035009, DEFAULT_ON], |
2be0f9ab YO |
82 | 'deprecated::delimiter_will_be_paired' => [ 5.035010, DEFAULT_ON], |
83 | 'deprecated::apostrophe_as_package_separator' | |
84 | => [ 5.037009, DEFAULT_ON], | |
bb7d7c52 | 85 | 'deprecated::smartmatch' => [ 5.037010, DEFAULT_ON], |
f1cf82e7 YO |
86 | 'deprecated::missing_import_called_with_args' |
87 | => [ 5.039010, DEFAULT_ON], | |
d81b4f93 | 88 | }], |
3c3f8cd6 AB |
89 | 'void' => [ 5.008, DEFAULT_OFF], |
90 | 'recursion' => [ 5.008, DEFAULT_OFF], | |
91 | 'redefine' => [ 5.008, DEFAULT_OFF], | |
92 | 'numeric' => [ 5.008, DEFAULT_OFF], | |
93 | 'uninitialized' => [ 5.008, DEFAULT_OFF], | |
94 | 'once' => [ 5.008, DEFAULT_OFF], | |
95 | 'misc' => [ 5.008, DEFAULT_OFF], | |
96 | 'regexp' => [ 5.008, DEFAULT_OFF], | |
97 | 'glob' => [ 5.008, DEFAULT_ON], | |
98 | 'untie' => [ 5.008, DEFAULT_OFF], | |
99 | 'substr' => [ 5.008, DEFAULT_OFF], | |
100 | 'taint' => [ 5.008, DEFAULT_OFF], | |
101 | 'signal' => [ 5.008, DEFAULT_OFF], | |
102 | 'closure' => [ 5.008, DEFAULT_OFF], | |
103 | 'overflow' => [ 5.008, DEFAULT_OFF], | |
104 | 'portable' => [ 5.008, DEFAULT_OFF], | |
105 | 'utf8' => [ 5.008, { | |
106 | 'surrogate' => [ 5.013, DEFAULT_OFF], | |
107 | 'nonchar' => [ 5.013, DEFAULT_OFF], | |
108 | 'non_unicode' => [ 5.013, DEFAULT_OFF], | |
109 | }], | |
110 | 'exiting' => [ 5.008, DEFAULT_OFF], | |
111 | 'pack' => [ 5.008, DEFAULT_OFF], | |
112 | 'unpack' => [ 5.008, DEFAULT_OFF], | |
113 | 'threads' => [ 5.008, DEFAULT_OFF], | |
114 | 'imprecision' => [ 5.011, DEFAULT_OFF], | |
115 | 'experimental' => [ 5.017, { | |
116 | 'experimental::lexical_subs' => | |
117 | [ 5.017, DEFAULT_ON ], | |
118 | 'experimental::regex_sets' => | |
737a7c2c | 119 | [ 5.017, DEFAULT_OFF ], |
3c3f8cd6 AB |
120 | 'experimental::smartmatch' => |
121 | [ 5.017, DEFAULT_ON ], | |
122 | 'experimental::postderef' => | |
123 | [ 5.019, DEFAULT_ON ], | |
3c3f8cd6 AB |
124 | 'experimental::signatures' => |
125 | [ 5.019, DEFAULT_ON ], | |
3c3f8cd6 AB |
126 | 'experimental::refaliasing' => |
127 | [ 5.021, DEFAULT_ON ], | |
128 | 'experimental::re_strict' => | |
129 | [ 5.021, DEFAULT_ON ], | |
130 | 'experimental::const_attr' => | |
131 | [ 5.021, DEFAULT_ON ], | |
9f88e537 FC |
132 | 'experimental::bitwise' => |
133 | [ 5.021, DEFAULT_ON ], | |
88d5dae9 FC |
134 | 'experimental::declared_refs' => |
135 | [ 5.025, DEFAULT_ON ], | |
0d76344b KW |
136 | 'experimental::script_run' => |
137 | [ 5.027, DEFAULT_ON ], | |
948f26d8 KW |
138 | 'experimental::alpha_assertions' => |
139 | [ 5.027, DEFAULT_ON ], | |
21c34e97 KW |
140 | 'experimental::private_use' => |
141 | [ 5.029, DEFAULT_ON ], | |
4fa1c4b6 KW |
142 | 'experimental::uniprop_wildcards' => |
143 | [ 5.029, DEFAULT_ON ], | |
15a9bc0d KW |
144 | 'experimental::vlb' => |
145 | [ 5.029, DEFAULT_ON ], | |
813e85a0 PE |
146 | 'experimental::isa' => |
147 | [ 5.031, DEFAULT_ON ], | |
a1325b90 PE |
148 | 'experimental::try' => |
149 | [ 5.033, DEFAULT_ON ], | |
f79e2ff9 PE |
150 | 'experimental::defer' => |
151 | [ 5.035, DEFAULT_ON ], | |
3b54923c NC |
152 | 'experimental::for_list' => |
153 | [ 5.035, DEFAULT_ON ], | |
59802880 PE |
154 | 'experimental::builtin' => |
155 | [ 5.035, DEFAULT_ON ], | |
1c547c3e PE |
156 | 'experimental::args_array_with_signatures' => |
157 | [ 5.035, DEFAULT_ON], | |
9c9853e8 KW |
158 | 'experimental::extra_paired_delimiters' => |
159 | [ 5.035, DEFAULT_ON], | |
99b497aa PE |
160 | 'experimental::class' => |
161 | [ 5.037, DEFAULT_ON ], | |
3c3f8cd6 AB |
162 | }], |
163 | ||
164 | 'missing' => [ 5.021, DEFAULT_OFF], | |
165 | 'redundant' => [ 5.021, DEFAULT_OFF], | |
166 | 'locale' => [ 5.021, DEFAULT_ON], | |
52e3acf8 | 167 | 'shadow' => [ 5.027, DEFAULT_OFF], |
4c58833d | 168 | 'scalar' => [ 5.035, DEFAULT_OFF], |
3c3f8cd6 AB |
169 | |
170 | #'default' => [ 5.008, DEFAULT_ON ], | |
ea5519d6 | 171 | }]}; |
599cee73 | 172 | |
9e9fbd5d DM |
173 | |
174 | ||
175 | my @DEFAULTS; # List of category numbers which are DEFAULT_ON | |
176 | ||
177 | # for each category name, list which category number(s) | |
178 | # it enables; e.g. | |
179 | my %CATEGORIES; # { 'name' => [ 1,2,5], ... } | |
180 | ||
9e9fbd5d DM |
181 | my %VALUE_TO_NAME; # (index_number => [ 'NAME', version ], ...); |
182 | ||
183 | my %NAME_TO_VALUE; # ('NAME' => index_number, ....); | |
599cee73 | 184 | |
381382f7 | 185 | # the experiments were successful (or abandonned), |
d7e8a031 PBB |
186 | # so no warning bit is needed anymore |
187 | my %NO_BIT_FOR = map { ( uc $_ => 1, $_ => 1 ) } qw( | |
188 | experimental::lexical_subs | |
189 | experimental::postderef | |
190 | experimental::signatures | |
191 | experimental::bitwise | |
192 | experimental::alpha_assertions | |
193 | experimental::script_run | |
194 | experimental::isa | |
381382f7 | 195 | experimental::smartmatch |
d7e8a031 PBB |
196 | ); |
197 | ||
76f222d7 DM |
198 | ########################################################################### |
199 | ||
200 | # Generate a hash with keys being the version number and values | |
201 | # being a list of node names with that version, e.g. | |
202 | # | |
203 | # { '5.008' => [ 'all', 'closure', .. ], 5.021' => .... } | |
204 | # | |
205 | # A ref to the (initially empty) hash is passed as an arg, which is | |
206 | # recursively populated | |
0d658bf5 PM |
207 | |
208 | sub valueWalk | |
209 | { | |
c3193e2d | 210 | my ($tree, $v_list) = @_; |
0d658bf5 PM |
211 | my ($k, $v) ; |
212 | ||
c3193e2d DM |
213 | foreach $k (sort keys %$tree) { |
214 | $v = $tree->{$k}; | |
9824c081 MS |
215 | die "Value associated with key '$k' is not an ARRAY reference" |
216 | if !ref $v || ref $v ne 'ARRAY' ; | |
0d658bf5 | 217 | |
d81b4f93 YO |
218 | my ($ver, $rest, $rest2) = @{ $v } ; |
219 | my $ref = ref $rest ? $rest : $rest2; | |
76f222d7 | 220 | push @{ $v_list->{$ver} }, $k; |
c4a853d1 | 221 | |
d81b4f93 YO |
222 | if (ref $ref) |
223 | { valueWalk ($ref, $v_list) } | |
0d658bf5 | 224 | } |
0d658bf5 PM |
225 | } |
226 | ||
76f222d7 DM |
227 | |
228 | # Assign an index number to each category, ordered by introduced-version. | |
229 | # Populate: | |
230 | # | |
231 | # %VALUE_TO_NAME = (index_number => [ 'NAME', version ], ...); | |
232 | # %NAME_TO_VALUE = ('NAME' => index_number, ....); | |
233 | # | |
234 | # Returns count of categories. | |
235 | ||
236 | ||
0d658bf5 PM |
237 | sub orderValues |
238 | { | |
c3193e2d | 239 | my ($tree) = @_; |
76f222d7 DM |
240 | |
241 | my %v_list; | |
c3193e2d | 242 | valueWalk($tree, \%v_list); |
76f222d7 | 243 | |
0d658bf5 PM |
244 | my $index = 0; |
245 | foreach my $ver ( sort { $a <=> $b } keys %v_list ) { | |
246 | foreach my $name (@{ $v_list{$ver} } ) { | |
d7e8a031 | 247 | next if $NO_BIT_FOR{$name}; |
9e9fbd5d DM |
248 | $VALUE_TO_NAME{ $index } = [ uc $name, $ver ] ; |
249 | $NAME_TO_VALUE{ uc $name } = $index ++ ; | |
0d658bf5 PM |
250 | } |
251 | } | |
252 | ||
253 | return $index ; | |
254 | } | |
255 | ||
5595fe1b | 256 | |
0d658bf5 PM |
257 | ########################################################################### |
258 | ||
5595fe1b DM |
259 | # Recurse the tree and populate |
260 | # %CATEGORIES | |
261 | # %DEFAULTS | |
262 | ||
599cee73 PM |
263 | sub walk |
264 | { | |
c3193e2d | 265 | my $tree = shift ; |
599cee73 PM |
266 | my @list = () ; |
267 | my ($k, $v) ; | |
268 | ||
c3193e2d DM |
269 | foreach $k (sort keys %$tree) { |
270 | $v = $tree->{$k}; | |
9e9fbd5d | 271 | die "duplicate key $k\n" if defined $CATEGORIES{$k} ; |
d7e8a031 | 272 | next if $NO_BIT_FOR{$k}; |
9824c081 | 273 | die "Can't find key '$k'" |
9e9fbd5d DM |
274 | if ! defined $NAME_TO_VALUE{uc $k} ; |
275 | push @{ $CATEGORIES{$k} }, $NAME_TO_VALUE{uc $k} ; | |
9824c081 MS |
276 | die "Value associated with key '$k' is not an ARRAY reference" |
277 | if !ref $v || ref $v ne 'ARRAY' ; | |
c4a853d1 | 278 | |
d81b4f93 YO |
279 | my ($ver, $rest, $rest2) = @{ $v } ; |
280 | my $ref = ref $rest ? $rest : $rest2; | |
281 | if (!ref $rest and $rest == DEFAULT_ON) | |
9e9fbd5d | 282 | { push @DEFAULTS, $NAME_TO_VALUE{uc $k} } |
d81b4f93 YO |
283 | if (ref $ref) |
284 | { push (@{ $CATEGORIES{$k} }, walk ($ref)) } | |
0d658bf5 | 285 | |
9e9fbd5d | 286 | push @list, @{ $CATEGORIES{$k} } ; |
599cee73 PM |
287 | } |
288 | ||
289 | return @list ; | |
599cee73 PM |
290 | } |
291 | ||
5595fe1b | 292 | |
599cee73 PM |
293 | ########################################################################### |
294 | ||
5595fe1b DM |
295 | # convert a list like (1,2,3,7,8) into a string like '1..3,7,8' |
296 | ||
599cee73 PM |
297 | sub mkRange |
298 | { | |
573a192d DIM |
299 | my @in = @_ ; |
300 | my @out = @in ; | |
599cee73 | 301 | |
573a192d | 302 | for my $i (1 .. @in - 1) { |
9824c081 | 303 | $out[$i] = ".." |
573a192d DIM |
304 | if $in[$i] == $in[$i - 1] + 1 |
305 | && ($i >= @in - 1 || $in[$i] + 1 == $in[$i + 1] ); | |
599cee73 | 306 | } |
573a192d | 307 | $out[-1] = $in[-1] if $out[-1] eq ".."; |
599cee73 PM |
308 | |
309 | my $out = join(",",@out); | |
310 | ||
311 | $out =~ s/,(\.\.,)+/../g ; | |
312 | return $out; | |
313 | } | |
314 | ||
5595fe1b | 315 | |
599cee73 | 316 | ########################################################################### |
5595fe1b DM |
317 | |
318 | # return a string containing a visual representation of the warnings tree | |
319 | # structure. | |
320 | ||
e15f14b8 | 321 | sub warningsTree |
e476b1b5 | 322 | { |
c3193e2d | 323 | my $tree = shift ; |
e476b1b5 | 324 | my $prefix = shift ; |
e476b1b5 GS |
325 | my ($k, $v) ; |
326 | ||
c3193e2d DM |
327 | my $max = (sort {$a <=> $b} map { length $_ } keys %$tree)[-1] ; |
328 | my @keys = sort keys %$tree ; | |
e476b1b5 | 329 | |
e15f14b8 RS |
330 | my $rv = ''; |
331 | ||
0d658bf5 | 332 | while ($k = shift @keys) { |
d7e8a031 | 333 | next if $NO_BIT_FOR{$k}; |
c3193e2d | 334 | $v = $tree->{$k}; |
9824c081 MS |
335 | die "Value associated with key '$k' is not an ARRAY reference" |
336 | if !ref $v || ref $v ne 'ARRAY' ; | |
c4a853d1 | 337 | |
0d658bf5 | 338 | my $offset ; |
0144c000 | 339 | if ($tree ne $WARNING_TREE) { |
9824c081 MS |
340 | $rv .= $prefix . "|\n" ; |
341 | $rv .= $prefix . "+- $k" ; | |
342 | $offset = ' ' x ($max + 4) ; | |
343 | } | |
344 | else { | |
345 | $rv .= $prefix . "$k" ; | |
346 | $offset = ' ' x ($max + 1) ; | |
347 | } | |
348 | ||
d81b4f93 YO |
349 | my ($ver, $rest, $rest2) = @{ $v } ; |
350 | my $ref = ref $rest ? $rest : $rest2; | |
351 | if (ref $ref) | |
9824c081 MS |
352 | { |
353 | my $bar = @keys ? "|" : " "; | |
354 | $rv .= " -" . "-" x ($max - length $k ) . "+\n" ; | |
d81b4f93 | 355 | $rv .= warningsTree ($ref, $prefix . $bar . $offset ) |
9824c081 MS |
356 | } |
357 | else | |
358 | { $rv .= "\n" } | |
e476b1b5 GS |
359 | } |
360 | ||
e15f14b8 | 361 | return $rv; |
e476b1b5 GS |
362 | } |
363 | ||
5595fe1b | 364 | |
e476b1b5 | 365 | ########################################################################### |
599cee73 | 366 | |
5595fe1b DM |
367 | # common backend for mkHex() and mkOct() |
368 | ||
317ea90d | 369 | sub mkHexOct |
599cee73 | 370 | { |
573a192d | 371 | my ($f, $max, @bits) = @_ ; |
599cee73 PM |
372 | my $mask = "\x00" x $max ; |
373 | my $string = "" ; | |
374 | ||
573a192d | 375 | foreach (@bits) { |
9824c081 | 376 | vec($mask, $_, 1) = 1 ; |
599cee73 PM |
377 | } |
378 | ||
599cee73 | 379 | foreach (unpack("C*", $mask)) { |
317ea90d MS |
380 | if ($f eq 'x') { |
381 | $string .= '\x' . sprintf("%2.2x", $_) | |
382 | } | |
383 | else { | |
384 | $string .= '\\' . sprintf("%o", $_) | |
385 | } | |
599cee73 PM |
386 | } |
387 | return $string ; | |
388 | } | |
389 | ||
5595fe1b DM |
390 | # Convert a list of bit offsets (0...) into a string containing $max bytes |
391 | # of the form "\xMM\xNN...." | |
392 | ||
317ea90d MS |
393 | sub mkHex |
394 | { | |
573a192d DIM |
395 | my($max, @bits) = @_; |
396 | return mkHexOct("x", $max, @bits); | |
317ea90d MS |
397 | } |
398 | ||
5595fe1b DM |
399 | # Like mkHex(), but outputs "\o..." instead |
400 | ||
317ea90d MS |
401 | sub mkOct |
402 | { | |
573a192d DIM |
403 | my($max, @bits) = @_; |
404 | return mkHexOct("o", $max, @bits); | |
317ea90d MS |
405 | } |
406 | ||
5595fe1b | 407 | |
599cee73 | 408 | ########################################################################### |
0144c000 | 409 | sub main { |
599cee73 | 410 | |
0144c000 YO |
411 | if (@ARGV && $ARGV[0] eq "tree") |
412 | { | |
413 | print warningsTree($WARNING_TREE, " ") ; | |
414 | exit ; | |
415 | } | |
599cee73 | 416 | |
0144c000 YO |
417 | my ($warn_h, $warn_pm) = map { |
418 | open_new($_, '>', { by => 'regen/warnings.pl' }); | |
419 | } 'warnings.h', 'lib/warnings.pm'; | |
c4a853d1 | 420 | |
0144c000 | 421 | my ($index, $warn_size); |
c4a853d1 | 422 | |
0144c000 | 423 | # generate warnings.h |
599cee73 | 424 | |
0144c000 | 425 | print $warn_h warnings_h_boilerplate_1(); |
599cee73 | 426 | |
0144c000 | 427 | $index = orderValues($WARNING_TREE); |
599cee73 | 428 | |
0144c000 YO |
429 | die <<~EOM if $index > 255 ; |
430 | Too many warnings categories -- max is 255 | |
431 | rewrite packWARN* & unpackWARN* macros | |
432 | EOM | |
c561877e | 433 | |
0144c000 YO |
434 | walk ($WARNING_TREE) ; |
435 | for (my $i = $index; $i & 3; $i++) { | |
436 | push @{$CATEGORIES{all}}, $i; | |
437 | } | |
3d09c062 | 438 | |
0144c000 YO |
439 | $index *= 2 ; |
440 | $warn_size = int($index / 8) + ($index % 8 != 0) ; | |
441 | ||
442 | my $k ; | |
443 | my $last_ver = 0; | |
444 | my @names; | |
445 | foreach $k (sort { $a <=> $b } keys %VALUE_TO_NAME) { | |
446 | my ($name, $version) = @{ $VALUE_TO_NAME{$k} }; | |
447 | print $warn_h "\n/* Warnings Categories added in Perl $version */\n\n" | |
448 | if $last_ver != $version ; | |
449 | $name =~ y/:/_/; | |
450 | $name = "WARN_$name"; | |
451 | print $warn_h tab(6, "#define $name"), " $k\n" ; | |
452 | push @names, $name; | |
453 | $last_ver = $version ; | |
454 | } | |
c561877e | 455 | |
0144c000 YO |
456 | print $warn_h tab(6, '#define WARNsize'), " $warn_size\n" ; |
457 | print $warn_h tab(6, '#define WARN_ALLstring'), ' "', ('\125' x $warn_size) , "\"\n" ; | |
458 | print $warn_h tab(6, '#define WARN_NONEstring'), ' "', ('\0' x $warn_size) , "\"\n" ; | |
c561877e | 459 | |
0144c000 | 460 | print $warn_h warnings_h_boilerplate_2(); |
c561877e | 461 | |
0144c000 YO |
462 | print $warn_h "\n\n/*\n" ; |
463 | print $warn_h map { "=for apidoc Amnh||$_\n" } @names; | |
464 | print $warn_h "\n=cut\n*/\n\n" ; | |
465 | print $warn_h "/* end of file warnings.h */\n"; | |
1e4d0e87 | 466 | |
0144c000 | 467 | read_only_bottom_close_and_rename($warn_h); |
1e4d0e87 | 468 | |
c561877e | 469 | |
0144c000 | 470 | # generate warnings.pm |
3d09c062 | 471 | |
0144c000 YO |
472 | while (<DATA>) { |
473 | last if /^VERSION$/ ; | |
474 | print $warn_pm $_ ; | |
475 | } | |
3d09c062 | 476 | |
0144c000 | 477 | print $warn_pm qq(our \$VERSION = "$::VERSION";\n); |
3d09c062 | 478 | |
0144c000 YO |
479 | while (<DATA>) { |
480 | last if /^KEYWORDS$/ ; | |
481 | print $warn_pm $_ ; | |
3d09c062 | 482 | } |
3d09c062 | 483 | |
0144c000 YO |
484 | $last_ver = 0; |
485 | print $warn_pm "our %Offsets = (" ; | |
486 | foreach my $k (sort { $a <=> $b } keys %VALUE_TO_NAME) { | |
487 | my ($name, $version) = @{ $VALUE_TO_NAME{$k} }; | |
488 | $name = lc $name; | |
489 | $k *= 2 ; | |
490 | if ( $last_ver != $version ) { | |
491 | print $warn_pm "\n"; | |
492 | print $warn_pm tab(6, " # Warnings Categories added in Perl $version"); | |
493 | print $warn_pm "\n"; | |
494 | } | |
495 | print $warn_pm tab(6, " '$name'"), "=> $k,\n" ; | |
496 | $last_ver = $version; | |
497 | } | |
3d09c062 | 498 | |
0144c000 | 499 | print $warn_pm ");\n\n" ; |
3d09c062 | 500 | |
0144c000 YO |
501 | print $warn_pm "our %Bits = (\n" ; |
502 | foreach my $k (sort keys %CATEGORIES) { | |
3d09c062 | 503 | |
0144c000 YO |
504 | my $v = $CATEGORIES{$k} ; |
505 | my @list = sort { $a <=> $b } @$v ; | |
3d09c062 | 506 | |
0144c000 YO |
507 | print $warn_pm tab(6, " '$k'"), '=> "', |
508 | mkHex($warn_size, map $_ * 2 , @list), | |
509 | '", # [', mkRange(@list), "]\n" ; | |
510 | } | |
3d09c062 | 511 | |
0144c000 | 512 | print $warn_pm ");\n\n" ; |
3d09c062 | 513 | |
0144c000 YO |
514 | print $warn_pm "our %DeadBits = (\n" ; |
515 | foreach my $k (sort keys %CATEGORIES) { | |
3d09c062 | 516 | |
0144c000 YO |
517 | my $v = $CATEGORIES{$k} ; |
518 | my @list = sort { $a <=> $b } @$v ; | |
3d09c062 | 519 | |
0144c000 YO |
520 | print $warn_pm tab(6, " '$k'"), '=> "', |
521 | mkHex($warn_size, map $_ * 2 + 1 , @list), | |
522 | '", # [', mkRange(@list), "]\n" ; | |
523 | } | |
d7e8a031 | 524 | |
0144c000 | 525 | print $warn_pm ");\n\n" ; |
d7e8a031 | 526 | |
0144c000 YO |
527 | print $warn_pm "our %NoOp = (\n" ; |
528 | foreach my $k ( grep /\A[a-z:_]+\z/, sort keys %NO_BIT_FOR ) { | |
529 | print $warn_pm tab(6, " '$k'"), "=> 1,\n"; | |
3d09c062 | 530 | } |
3d09c062 | 531 | |
0144c000 YO |
532 | print $warn_pm ");\n\n" ; |
533 | print $warn_pm "# These are used by various things, including our own tests\n"; | |
534 | print $warn_pm tab(6, 'our $NONE'), '= "', ('\0' x $warn_size) , "\";\n" ; | |
535 | print $warn_pm tab(6, 'our $DEFAULT'), '= "', | |
536 | mkHex($warn_size, map $_ * 2, @DEFAULTS), | |
537 | '"; # [', mkRange(sort { $a <=> $b } @DEFAULTS), "]\n" ; | |
538 | print $warn_pm tab(6, 'our $LAST_BIT'), '= ' . "$index ;\n" ; | |
539 | print $warn_pm tab(6, 'our $BYTES'), '= ' . "$warn_size ;\n" ; | |
540 | while (<DATA>) { | |
541 | if ($_ eq "=for warnings.pl tree-goes-here\n") { | |
542 | print $warn_pm warningsTree($WARNING_TREE, " "); | |
543 | next; | |
544 | } | |
545 | print $warn_pm $_ ; | |
546 | } | |
3d09c062 | 547 | |
0144c000 | 548 | read_only_bottom_close_and_rename($warn_pm); |
3d09c062 | 549 | |
0144c000 YO |
550 | exit(0); |
551 | } | |
3d09c062 | 552 | |
0144c000 | 553 | main() unless caller(); |
3d09c062 DM |
554 | # ----------------------------------------------------------------- |
555 | ||
556 | sub warnings_h_boilerplate_1 { return <<'EOM'; } | |
557 | ||
558 | #define Perl_Warn_Off_(x) ((x) / 8) | |
559 | #define Perl_Warn_Bit_(x) (1 << ((x) % 8)) | |
560 | #define PerlWarnIsSet_(a, x) ((a)[Perl_Warn_Off_(x)] & Perl_Warn_Bit_(x)) | |
561 | ||
3d09c062 DM |
562 | #define G_WARN_OFF 0 /* $^W == 0 */ |
563 | #define G_WARN_ON 1 /* -w flag and $^W != 0 */ | |
564 | #define G_WARN_ALL_ON 2 /* -W flag */ | |
565 | #define G_WARN_ALL_OFF 4 /* -X flag */ | |
566 | #define G_WARN_ONCE 8 /* set if 'once' ever enabled */ | |
567 | #define G_WARN_ALL_MASK (G_WARN_ALL_ON|G_WARN_ALL_OFF) | |
568 | ||
569 | #define pWARN_STD NULL | |
f8552c1a YO |
570 | #define pWARN_ALL &PL_WARN_ALL /* use warnings 'all' */ |
571 | #define pWARN_NONE &PL_WARN_NONE /* no warnings 'all' */ | |
3d09c062 DM |
572 | |
573 | #define specialWARN(x) ((x) == pWARN_STD || (x) == pWARN_ALL || \ | |
574 | (x) == pWARN_NONE) | |
575 | ||
576 | /* if PL_warnhook is set to this value, then warnings die */ | |
577 | #define PERL_WARNHOOK_FATAL (&PL_sv_placeholder) | |
578 | EOM | |
579 | ||
580 | # ----------------------------------------------------------------- | |
581 | ||
582 | sub warnings_h_boilerplate_2 { return <<'EOM'; } | |
599cee73 | 583 | |
a2637ca0 | 584 | #define isLEXWARN_on \ |
9824c081 | 585 | cBOOL(PL_curcop && PL_curcop->cop_warnings != pWARN_STD) |
a2637ca0 | 586 | #define isLEXWARN_off \ |
9824c081 | 587 | cBOOL(!PL_curcop || PL_curcop->cop_warnings == pWARN_STD) |
d5a71f30 | 588 | #define isWARN_ONCE (PL_dowarn & (G_WARN_ON|G_WARN_ONCE)) |
f8552c1a | 589 | #define hasWARNBIT(c,x) (RCPV_LEN(c) > (2*(x)/8)) |
f0774ef1 | 590 | #define isWARN_on(c,x) (hasWARNBIT(c,x) \ |
f8552c1a | 591 | ? PerlWarnIsSet_((U8 *)(c), 2*(x)) \ |
f0774ef1 YO |
592 | : 0) |
593 | #define isWARNf_on(c,x) (hasWARNBIT(c,x) \ | |
f8552c1a | 594 | ? PerlWarnIsSet_((U8 *)(c), 2*(x)+1) \ |
f0774ef1 | 595 | : 0) |
72dc9ed5 | 596 | |
c1e47bad | 597 | #define DUP_WARNINGS(p) Perl_dup_warnings(aTHX_ p) |
d5a71f30 | 598 | |
94c8b9c1 | 599 | #define free_and_set_cop_warnings(cmp,w) STMT_START { \ |
f8552c1a | 600 | if (!specialWARN((cmp)->cop_warnings)) rcpv_free((cmp)->cop_warnings); \ |
1943af61 | 601 | (cmp)->cop_warnings = w; \ |
94c8b9c1 N |
602 | } STMT_END |
603 | ||
feff94e1 KW |
604 | /* |
605 | ||
606 | =head1 Warning and Dieing | |
607 | ||
bb3eff5d KW |
608 | In all these calls, the C<U32 wI<n>> parameters are warning category |
609 | constants. You can see the ones currently available in | |
610 | L<warnings/Category Hierarchy>, just capitalize all letters in the names | |
611 | and prefix them by C<WARN_>. So, for example, the category C<void> used in a | |
612 | perl program becomes C<WARN_VOID> when used in XS code and passed to one of | |
613 | the calls below. | |
614 | ||
feff94e1 | 615 | =for apidoc Am|bool|ckWARN|U32 w |
0afc88d2 KW |
616 | =for apidoc_item ||ckWARN2|U32 w1|U32 w2 |
617 | =for apidoc_item ||ckWARN3|U32 w1|U32 w2|U32 w3 | |
618 | =for apidoc_item ||ckWARN4|U32 w1|U32 w2|U32 w3|U32 w4 | |
619 | These return a boolean as to whether or not warnings are enabled for any of | |
620 | the warning category(ies) parameters: C<w>, C<w1>, .... | |
feff94e1 | 621 | |
0afc88d2 KW |
622 | Should any of the categories by default be enabled even if not within the |
623 | scope of S<C<use warnings>>, instead use the C<L</ckWARN_d>> macros. | |
feff94e1 | 624 | |
0afc88d2 KW |
625 | The categories must be completely independent, one may not be subclassed from |
626 | the other. | |
feff94e1 | 627 | |
0afc88d2 | 628 | =for apidoc Am|bool|ckWARN_d|U32 w |
b8a2649a KW |
629 | =for apidoc_item ||ckWARN2_d|U32 w1|U32 w2 |
630 | =for apidoc_item ||ckWARN3_d|U32 w1|U32 w2|U32 w3 | |
631 | =for apidoc_item ||ckWARN4_d|U32 w1|U32 w2|U32 w3|U32 w4 | |
feff94e1 | 632 | |
0afc88d2 | 633 | Like C<L</ckWARN>>, but for use if and only if the warning category(ies) is by |
feff94e1 KW |
634 | default enabled even if not within the scope of S<C<use warnings>>. |
635 | ||
b8a2649a KW |
636 | =for apidoc Am|U32|packWARN|U32 w1 |
637 | =for apidoc_item ||packWARN2|U32 w1|U32 w2 | |
638 | =for apidoc_item ||packWARN3|U32 w1|U32 w2|U32 w3 | |
639 | =for apidoc_item ||packWARN4|U32 w1|U32 w2|U32 w3|U32 w4 | |
640 | ||
641 | These macros are used to pack warning categories into a single U32 to pass to | |
642 | macros and functions that take a warning category parameter. The number of | |
643 | categories to pack is given by the name, with a corresponding number of | |
644 | category parameters passed. | |
feff94e1 KW |
645 | |
646 | =cut | |
647 | ||
648 | */ | |
649 | ||
f54ba1c2 | 650 | #define ckWARN(w) Perl_ckwarn(aTHX_ packWARN(w)) |
7c08c4c5 KW |
651 | |
652 | /* The w1, w2 ... should be independent warnings categories; one shouldn't be | |
653 | * a subcategory of any other */ | |
654 | ||
f54ba1c2 DM |
655 | #define ckWARN2(w1,w2) Perl_ckwarn(aTHX_ packWARN2(w1,w2)) |
656 | #define ckWARN3(w1,w2,w3) Perl_ckwarn(aTHX_ packWARN3(w1,w2,w3)) | |
657 | #define ckWARN4(w1,w2,w3,w4) Perl_ckwarn(aTHX_ packWARN4(w1,w2,w3,w4)) | |
658 | ||
659 | #define ckWARN_d(w) Perl_ckwarn_d(aTHX_ packWARN(w)) | |
660 | #define ckWARN2_d(w1,w2) Perl_ckwarn_d(aTHX_ packWARN2(w1,w2)) | |
661 | #define ckWARN3_d(w1,w2,w3) Perl_ckwarn_d(aTHX_ packWARN3(w1,w2,w3)) | |
662 | #define ckWARN4_d(w1,w2,w3,w4) Perl_ckwarn_d(aTHX_ packWARN4(w1,w2,w3,w4)) | |
12bcd1a6 | 663 | |
98fe6610 NC |
664 | #define WARNshift 8 |
665 | ||
3b9e3074 | 666 | #define packWARN(a) (a ) |
7c08c4c5 KW |
667 | |
668 | /* The a, b, ... should be independent warnings categories; one shouldn't be | |
669 | * a subcategory of any other */ | |
670 | ||
3b9e3074 SH |
671 | #define packWARN2(a,b) ((a) | ((b)<<8) ) |
672 | #define packWARN3(a,b,c) ((a) | ((b)<<8) | ((c)<<16) ) | |
673 | #define packWARN4(a,b,c,d) ((a) | ((b)<<8) | ((c)<<16) | ((d) <<24)) | |
12bcd1a6 | 674 | |
0132fc56 KW |
675 | #define unpackWARN1(x) ((U8) (x) ) |
676 | #define unpackWARN2(x) ((U8) ((x) >> 8)) | |
677 | #define unpackWARN3(x) ((U8) ((x) >> 16)) | |
678 | #define unpackWARN4(x) ((U8) ((x) >> 24)) | |
12bcd1a6 PM |
679 | |
680 | #define ckDEAD(x) \ | |
006c1a1d Z |
681 | (PL_curcop && \ |
682 | !specialWARN(PL_curcop->cop_warnings) && \ | |
683 | (isWARNf_on(PL_curcop->cop_warnings, unpackWARN1(x)) || \ | |
684 | (unpackWARN2(x) && \ | |
9824c081 MS |
685 | (isWARNf_on(PL_curcop->cop_warnings, unpackWARN2(x)) || \ |
686 | (unpackWARN3(x) && \ | |
687 | (isWARNf_on(PL_curcop->cop_warnings, unpackWARN3(x)) || \ | |
688 | (unpackWARN4(x) && \ | |
689 | isWARNf_on(PL_curcop->cop_warnings, unpackWARN4(x))))))))) | |
12bcd1a6 | 690 | |
599cee73 PM |
691 | EOM |
692 | ||
3d09c062 | 693 | # ----------------------------------------------------------------- |
599cee73 PM |
694 | |
695 | __END__ | |
4438c4b7 | 696 | package warnings; |
599cee73 | 697 | |
3d8ff825 | 698 | VERSION |
f2c3e829 RGS |
699 | |
700 | # Verify that we're called correctly so that warnings will work. | |
67ba812d AP |
701 | # Can't use Carp, since Carp uses us! |
702 | # String regexps because constant folding = smaller optree = less memory vs regexp literal | |
f2c3e829 | 703 | # see also strict.pm. |
67ba812d AP |
704 | die sprintf "Incorrect use of pragma '%s' at %s line %d.\n", __PACKAGE__, +(caller)[1,2] |
705 | if __FILE__ !~ ( '(?x) \b '.__PACKAGE__.' \.pmc? \z' ) | |
706 | && __FILE__ =~ ( '(?x) \b (?i:'.__PACKAGE__.') \.pmc? \z' ); | |
b75c8c73 | 707 | |
effd17dc DD |
708 | KEYWORDS |
709 | ||
effd17dc DD |
710 | sub Croaker |
711 | { | |
712 | require Carp; # this initializes %CarpInternal | |
713 | local $Carp::CarpInternal{'warnings'}; | |
714 | delete $Carp::CarpInternal{'warnings'}; | |
715 | Carp::croak(@_); | |
716 | } | |
717 | ||
006c1a1d Z |
718 | sub _expand_bits { |
719 | my $bits = shift; | |
720 | my $want_len = ($LAST_BIT + 7) >> 3; | |
721 | my $len = length($bits); | |
722 | if ($len != $want_len) { | |
9824c081 MS |
723 | if ($bits eq "") { |
724 | $bits = "\x00" x $want_len; | |
725 | } elsif ($len > $want_len) { | |
726 | substr $bits, $want_len, $len-$want_len, ""; | |
727 | } else { | |
728 | my $x = vec($bits, $Offsets{all} >> 1, 2); | |
729 | $x |= $x << 2; | |
730 | $x |= $x << 4; | |
731 | $bits .= chr($x) x ($want_len - $len); | |
732 | } | |
006c1a1d Z |
733 | } |
734 | return $bits; | |
735 | } | |
736 | ||
effd17dc DD |
737 | sub _bits { |
738 | my $mask = shift ; | |
739 | my $catmask ; | |
740 | my $fatal = 0 ; | |
741 | my $no_fatal = 0 ; | |
742 | ||
006c1a1d | 743 | $mask = _expand_bits($mask); |
effd17dc | 744 | foreach my $word ( @_ ) { |
d7e8a031 | 745 | next if $NoOp{$word}; |
9824c081 MS |
746 | if ($word eq 'FATAL') { |
747 | $fatal = 1; | |
748 | $no_fatal = 0; | |
749 | } | |
750 | elsif ($word eq 'NONFATAL') { | |
751 | $fatal = 0; | |
752 | $no_fatal = 1; | |
753 | } | |
754 | elsif ($catmask = $Bits{$word}) { | |
755 | $mask |= $catmask ; | |
756 | $mask |= $DeadBits{$word} if $fatal ; | |
757 | $mask = ~(~$mask | $DeadBits{$word}) if $no_fatal ; | |
758 | } | |
759 | else | |
760 | { Croaker("Unknown warnings category '$word'")} | |
effd17dc DD |
761 | } |
762 | ||
763 | return $mask ; | |
764 | } | |
765 | ||
766 | sub bits | |
767 | { | |
768 | # called from B::Deparse.pm | |
769 | push @_, 'all' unless @_ ; | |
006c1a1d | 770 | return _bits("", @_) ; |
effd17dc DD |
771 | } |
772 | ||
773 | sub import | |
774 | { | |
e926558e | 775 | my $invocant = shift; |
effd17dc | 776 | |
006c1a1d Z |
777 | # append 'all' when implied (empty import list or after a lone |
778 | # "FATAL" or "NONFATAL") | |
779 | push @_, 'all' | |
e926558e DC |
780 | if !@_ || (@_==1 && ($_[0] eq 'FATAL' || $_[0] eq 'NONFATAL')); |
781 | ||
782 | my @fatal = (); | |
783 | foreach my $warning (@_) { | |
784 | if($warning =~ /^(NON)?FATAL$/) { | |
785 | @fatal = ($warning); | |
786 | } elsif(substr($warning, 0, 1) ne '-') { | |
787 | my $mask = ${^WARNING_BITS} // ($^W ? $Bits{all} : $DEFAULT) ; | |
788 | ${^WARNING_BITS} = _bits($mask, @fatal, $warning); | |
789 | } else { | |
790 | $invocant->unimport(substr($warning, 1)); | |
791 | } | |
792 | } | |
effd17dc DD |
793 | } |
794 | ||
795 | sub unimport | |
796 | { | |
797 | shift; | |
798 | ||
799 | my $catmask ; | |
800 | my $mask = ${^WARNING_BITS} // ($^W ? $Bits{all} : $DEFAULT) ; | |
801 | ||
effd17dc DD |
802 | # append 'all' when implied (empty import list or after a lone "FATAL") |
803 | push @_, 'all' if !@_ || @_==1 && $_[0] eq 'FATAL'; | |
804 | ||
006c1a1d | 805 | $mask = _expand_bits($mask); |
effd17dc | 806 | foreach my $word ( @_ ) { |
d7e8a031 | 807 | next if $NoOp{$word}; |
9824c081 MS |
808 | if ($word eq 'FATAL') { |
809 | next; | |
810 | } | |
811 | elsif ($catmask = $Bits{$word}) { | |
812 | $mask = ~(~$mask | $catmask | $DeadBits{$word}); | |
813 | } | |
814 | else | |
815 | { Croaker("Unknown warnings category '$word'")} | |
effd17dc DD |
816 | } |
817 | ||
818 | ${^WARNING_BITS} = $mask ; | |
819 | } | |
820 | ||
821 | my %builtin_type; @builtin_type{qw(SCALAR ARRAY HASH CODE REF GLOB LVALUE Regexp)} = (); | |
822 | ||
c4583f59 | 823 | sub LEVEL () { 8 }; |
effd17dc DD |
824 | sub MESSAGE () { 4 }; |
825 | sub FATAL () { 2 }; | |
826 | sub NORMAL () { 1 }; | |
827 | ||
828 | sub __chk | |
829 | { | |
830 | my $category ; | |
831 | my $offset ; | |
832 | my $isobj = 0 ; | |
833 | my $wanted = shift; | |
834 | my $has_message = $wanted & MESSAGE; | |
c4583f59 FC |
835 | my $has_level = $wanted & LEVEL ; |
836 | ||
837 | if ($has_level) { | |
9824c081 MS |
838 | if (@_ != ($has_message ? 3 : 2)) { |
839 | my $sub = (caller 1)[3]; | |
840 | my $syntax = $has_message | |
841 | ? "category, level, 'message'" | |
842 | : 'category, level'; | |
843 | Croaker("Usage: $sub($syntax)"); | |
c4583f59 FC |
844 | } |
845 | } | |
846 | elsif (not @_ == 1 || @_ == ($has_message ? 2 : 0)) { | |
9824c081 MS |
847 | my $sub = (caller 1)[3]; |
848 | my $syntax = $has_message ? "[category,] 'message'" : '[category]'; | |
849 | Croaker("Usage: $sub($syntax)"); | |
effd17dc DD |
850 | } |
851 | ||
852 | my $message = pop if $has_message; | |
853 | ||
854 | if (@_) { | |
9824c081 MS |
855 | # check the category supplied. |
856 | $category = shift ; | |
857 | if (my $type = ref $category) { | |
858 | Croaker("not an object") | |
859 | if exists $builtin_type{$type}; | |
860 | $category = $type; | |
861 | $isobj = 1 ; | |
862 | } | |
863 | $offset = $Offsets{$category}; | |
864 | Croaker("Unknown warnings category '$category'") | |
865 | unless defined $offset; | |
effd17dc DD |
866 | } |
867 | else { | |
b625025e | 868 | $category = caller(1); |
9824c081 MS |
869 | $offset = $Offsets{$category}; |
870 | Croaker("package '$category' not registered for warnings") | |
871 | unless defined $offset ; | |
effd17dc DD |
872 | } |
873 | ||
874 | my $i; | |
875 | ||
876 | if ($isobj) { | |
9824c081 MS |
877 | my $pkg; |
878 | $i = 2; | |
879 | while (do { { package DB; $pkg = (caller($i++))[0] } } ) { | |
880 | last unless @DB::args && $DB::args[0] =~ /^$category=/ ; | |
881 | } | |
882 | $i -= 2 ; | |
effd17dc | 883 | } |
c4583f59 | 884 | elsif ($has_level) { |
9824c081 | 885 | $i = 2 + shift; |
c4583f59 | 886 | } |
effd17dc | 887 | else { |
9824c081 | 888 | $i = _error_loc(); # see where Carp will allocate the error |
effd17dc DD |
889 | } |
890 | ||
891 | # Default to 0 if caller returns nothing. Default to $DEFAULT if it | |
892 | # explicitly returns undef. | |
893 | my(@callers_bitmask) = (caller($i))[9] ; | |
894 | my $callers_bitmask = | |
9824c081 | 895 | @callers_bitmask ? $callers_bitmask[0] // $DEFAULT : 0 ; |
006c1a1d | 896 | length($callers_bitmask) > ($offset >> 3) or $offset = $Offsets{all}; |
effd17dc DD |
897 | |
898 | my @results; | |
899 | foreach my $type (FATAL, NORMAL) { | |
9824c081 | 900 | next unless $wanted & $type; |
effd17dc | 901 | |
9824c081 | 902 | push @results, vec($callers_bitmask, $offset + $type - 1, 1); |
effd17dc DD |
903 | } |
904 | ||
905 | # &enabled and &fatal_enabled | |
906 | return $results[0] unless $has_message; | |
907 | ||
908 | # &warnif, and the category is neither enabled as warning nor as fatal | |
c4583f59 | 909 | return if ($wanted & (NORMAL | FATAL | MESSAGE)) |
9824c081 MS |
910 | == (NORMAL | FATAL | MESSAGE) |
911 | && !($results[0] || $results[1]); | |
effd17dc | 912 | |
c4583f59 FC |
913 | # If we have an explicit level, bypass Carp. |
914 | if ($has_level and @callers_bitmask) { | |
9824c081 MS |
915 | # logic copied from util.c:mess_sv |
916 | my $stuff = " at " . join " line ", (caller $i)[1,2]; | |
917 | $stuff .= sprintf ", <%s> %s %d", | |
918 | *${^LAST_FH}{NAME}, | |
919 | ($/ eq "\n" ? "line" : "chunk"), $. | |
920 | if $. && ${^LAST_FH}; | |
921 | die "$message$stuff.\n" if $results[0]; | |
922 | return warn "$message$stuff.\n"; | |
c4583f59 FC |
923 | } |
924 | ||
effd17dc DD |
925 | require Carp; |
926 | Carp::croak($message) if $results[0]; | |
927 | # will always get here for &warn. will only get here for &warnif if the | |
928 | # category is enabled | |
929 | Carp::carp($message); | |
930 | } | |
931 | ||
932 | sub _mkMask | |
933 | { | |
934 | my ($bit) = @_; | |
935 | my $mask = ""; | |
936 | ||
937 | vec($mask, $bit, 1) = 1; | |
938 | return $mask; | |
939 | } | |
940 | ||
941 | sub register_categories | |
942 | { | |
943 | my @names = @_; | |
944 | ||
945 | for my $name (@names) { | |
9824c081 MS |
946 | if (! defined $Bits{$name}) { |
947 | $Offsets{$name} = $LAST_BIT; | |
948 | $Bits{$name} = _mkMask($LAST_BIT++); | |
949 | $DeadBits{$name} = _mkMask($LAST_BIT++); | |
950 | if (length($Bits{$name}) > length($Bits{all})) { | |
951 | $Bits{all} .= "\x55"; | |
952 | $DeadBits{all} .= "\xaa"; | |
953 | } | |
954 | } | |
effd17dc DD |
955 | } |
956 | } | |
957 | ||
958 | sub _error_loc { | |
959 | require Carp; | |
960 | goto &Carp::short_error_loc; # don't introduce another stack frame | |
961 | } | |
962 | ||
963 | sub enabled | |
964 | { | |
965 | return __chk(NORMAL, @_); | |
966 | } | |
967 | ||
968 | sub fatal_enabled | |
969 | { | |
970 | return __chk(FATAL, @_); | |
971 | } | |
972 | ||
973 | sub warn | |
974 | { | |
975 | return __chk(FATAL | MESSAGE, @_); | |
976 | } | |
977 | ||
978 | sub warnif | |
979 | { | |
980 | return __chk(NORMAL | FATAL | MESSAGE, @_); | |
981 | } | |
982 | ||
c4583f59 FC |
983 | sub enabled_at_level |
984 | { | |
985 | return __chk(NORMAL | LEVEL, @_); | |
986 | } | |
987 | ||
988 | sub fatal_enabled_at_level | |
989 | { | |
990 | return __chk(FATAL | LEVEL, @_); | |
991 | } | |
992 | ||
993 | sub warn_at_level | |
994 | { | |
995 | return __chk(FATAL | MESSAGE | LEVEL, @_); | |
996 | } | |
997 | ||
998 | sub warnif_at_level | |
999 | { | |
1000 | return __chk(NORMAL | FATAL | MESSAGE | LEVEL, @_); | |
1001 | } | |
1002 | ||
effd17dc DD |
1003 | # These are not part of any public interface, so we can delete them to save |
1004 | # space. | |
c4583f59 | 1005 | delete @warnings::{qw(NORMAL FATAL MESSAGE LEVEL)}; |
effd17dc DD |
1006 | |
1007 | 1; | |
1008 | __END__ | |
4bbd41f5 | 1009 | |
599cee73 PM |
1010 | =head1 NAME |
1011 | ||
4438c4b7 | 1012 | warnings - Perl pragma to control optional warnings |
599cee73 PM |
1013 | |
1014 | =head1 SYNOPSIS | |
1015 | ||
4438c4b7 JH |
1016 | use warnings; |
1017 | no warnings; | |
599cee73 | 1018 | |
1c3cfd87 BC |
1019 | # Standard warnings are enabled by use v5.35 or above |
1020 | use v5.35; | |
1021 | ||
4438c4b7 | 1022 | use warnings "all"; |
e926558e DC |
1023 | no warnings "uninitialized"; |
1024 | ||
1025 | # or equivalent to those last two ... | |
1026 | use warnings qw(all -uninitialized); | |
599cee73 | 1027 | |
d3a7d8c7 GS |
1028 | use warnings::register; |
1029 | if (warnings::enabled()) { | |
1030 | warnings::warn("some warning"); | |
1031 | } | |
1032 | ||
1033 | if (warnings::enabled("void")) { | |
e476b1b5 GS |
1034 | warnings::warn("void", "some warning"); |
1035 | } | |
1036 | ||
7e6d00f8 PM |
1037 | if (warnings::enabled($object)) { |
1038 | warnings::warn($object, "some warning"); | |
1039 | } | |
1040 | ||
721f911b PM |
1041 | warnings::warnif("some warning"); |
1042 | warnings::warnif("void", "some warning"); | |
1043 | warnings::warnif($object, "some warning"); | |
7e6d00f8 | 1044 | |
599cee73 PM |
1045 | =head1 DESCRIPTION |
1046 | ||
188c4f6f RS |
1047 | The C<warnings> pragma gives control over which warnings are enabled in |
1048 | which parts of a Perl program. It's a more flexible alternative for | |
1049 | both the command line flag B<-w> and the equivalent Perl variable, | |
1050 | C<$^W>. | |
33edcb80 RS |
1051 | |
1052 | This pragma works just like the C<strict> pragma. | |
1053 | This means that the scope of the warning pragma is limited to the | |
1054 | enclosing block. It also means that the pragma setting will not | |
1055 | leak across files (via C<use>, C<require> or C<do>). This allows | |
1056 | authors to independently define the degree of warning checks that will | |
1057 | be applied to their module. | |
1058 | ||
1059 | By default, optional warnings are disabled, so any legacy code that | |
1060 | doesn't attempt to control the warnings will work unchanged. | |
1061 | ||
3c3f8cd6 | 1062 | All warnings are enabled in a block by either of these: |
33edcb80 RS |
1063 | |
1064 | use warnings; | |
1065 | use warnings 'all'; | |
1066 | ||
3c3f8cd6 | 1067 | Similarly all warnings are disabled in a block by either of these: |
33edcb80 RS |
1068 | |
1069 | no warnings; | |
1070 | no warnings 'all'; | |
1071 | ||
1072 | For example, consider the code below: | |
1073 | ||
1074 | use warnings; | |
573a192d | 1075 | my @x; |
33edcb80 RS |
1076 | { |
1077 | no warnings; | |
9824c081 | 1078 | my $y = @x[0]; |
33edcb80 | 1079 | } |
573a192d | 1080 | my $z = @x[0]; |
33edcb80 RS |
1081 | |
1082 | The code in the enclosing block has warnings enabled, but the inner | |
1083 | block has them disabled. In this case that means the assignment to the | |
cd2e5170 | 1084 | scalar C<$z> will trip the C<"Scalar value @x[0] better written as $x[0]"> |
573a192d | 1085 | warning, but the assignment to the scalar C<$y> will not. |
33edcb80 | 1086 | |
1c3cfd87 BC |
1087 | All warnings are enabled automatically within the scope of |
1088 | a C<L<use v5.35|perlfunc/use VERSION>> (or higher) declaration. | |
1089 | ||
33edcb80 RS |
1090 | =head2 Default Warnings and Optional Warnings |
1091 | ||
1092 | Before the introduction of lexical warnings, Perl had two classes of | |
56873d42 | 1093 | warnings: mandatory and optional. |
33edcb80 RS |
1094 | |
1095 | As its name suggests, if your code tripped a mandatory warning, you | |
1096 | would get a warning whether you wanted it or not. | |
1097 | For example, the code below would always produce an C<"isn't numeric"> | |
1098 | warning about the "2:". | |
1099 | ||
573a192d | 1100 | my $x = "2:" + 3; |
33edcb80 RS |
1101 | |
1102 | With the introduction of lexical warnings, mandatory warnings now become | |
1103 | I<default> warnings. The difference is that although the previously | |
1104 | mandatory warnings are still enabled by default, they can then be | |
1105 | subsequently enabled or disabled with the lexical warning pragma. For | |
1106 | example, in the code below, an C<"isn't numeric"> warning will only | |
573a192d | 1107 | be reported for the C<$x> variable. |
33edcb80 | 1108 | |
573a192d | 1109 | my $x = "2:" + 3; |
33edcb80 | 1110 | no warnings; |
573a192d | 1111 | my $y = "2:" + 3; |
33edcb80 RS |
1112 | |
1113 | Note that neither the B<-w> flag or the C<$^W> can be used to | |
1114 | disable/enable default warnings. They are still mandatory in this case. | |
1115 | ||
e926558e DC |
1116 | =head2 "Negative warnings" |
1117 | ||
1118 | As a convenience, you can (as of Perl 5.34) pass arguments to the | |
1119 | C<import()> method both positively and negatively. Negative warnings | |
1120 | are those with a C<-> sign prepended to their names; positive warnings | |
1121 | are anything else. This lets you turn on some warnings and turn off | |
1122 | others in one command. So, assuming that you've already turned on a | |
1123 | bunch of warnings but want to tweak them a bit in some block, you can | |
1124 | do this: | |
1125 | ||
1126 | { | |
1127 | use warnings qw(uninitialized -redefine); | |
1128 | ... | |
1129 | } | |
1130 | ||
1131 | which is equivalent to: | |
1132 | ||
1133 | { | |
1134 | use warnings qw(uninitialized); | |
1135 | no warnings qw(redefine); | |
1136 | ... | |
1137 | } | |
1138 | ||
1139 | The argument list is processed in the order you specify. So, for example, if you | |
1140 | don't want to be warned about use of experimental features, except for C<somefeature> | |
1141 | that you really dislike, you can say this: | |
1142 | ||
1143 | use warnings qw(all -experimental experimental::somefeature); | |
1144 | ||
1145 | which is equivalent to: | |
1146 | ||
1147 | use warnings 'all'; | |
1148 | no warnings 'experimental'; | |
1149 | use warnings 'experimental::somefeature'; | |
1150 | ||
d7e8a031 PBB |
1151 | As experimental features become regular features of Perl, |
1152 | the corresponding warnings are not printed anymore. | |
1153 | They also stop being listed in the L</Category Hierarchy> below. | |
1154 | ||
1155 | It is still possible to request turning on or off these warnings, | |
1156 | but doing so has no effect. | |
1157 | ||
33edcb80 RS |
1158 | =head2 What's wrong with B<-w> and C<$^W> |
1159 | ||
1160 | Although very useful, the big problem with using B<-w> on the command | |
1161 | line to enable warnings is that it is all or nothing. Take the typical | |
1162 | scenario when you are writing a Perl program. Parts of the code you | |
1163 | will write yourself, but it's very likely that you will make use of | |
1164 | pre-written Perl modules. If you use the B<-w> flag in this case, you | |
1165 | end up enabling warnings in pieces of code that you haven't written. | |
1166 | ||
1167 | Similarly, using C<$^W> to either disable or enable blocks of code is | |
1168 | fundamentally flawed. For a start, say you want to disable warnings in | |
1169 | a block of code. You might expect this to be enough to do the trick: | |
1170 | ||
1171 | { | |
1172 | local ($^W) = 0; | |
9824c081 MS |
1173 | my $x =+ 2; |
1174 | my $y; chop $y; | |
33edcb80 RS |
1175 | } |
1176 | ||
1177 | When this code is run with the B<-w> flag, a warning will be produced | |
573a192d | 1178 | for the C<$x> line: C<"Reversed += operator">. |
33edcb80 RS |
1179 | |
1180 | The problem is that Perl has both compile-time and run-time warnings. To | |
1181 | disable compile-time warnings you need to rewrite the code like this: | |
1182 | ||
1183 | { | |
1184 | BEGIN { $^W = 0 } | |
9824c081 MS |
1185 | my $x =+ 2; |
1186 | my $y; chop $y; | |
33edcb80 RS |
1187 | } |
1188 | ||
45f87e65 DB |
1189 | And note that unlike the first example, this will permanently set C<$^W> |
1190 | since it cannot both run during compile-time and be localized to a | |
1191 | run-time block. | |
1192 | ||
33edcb80 RS |
1193 | The other big problem with C<$^W> is the way you can inadvertently |
1194 | change the warning setting in unexpected places in your code. For example, | |
1195 | when the code below is run (without the B<-w> flag), the second call | |
1196 | to C<doit> will trip a C<"Use of uninitialized value"> warning, whereas | |
1197 | the first will not. | |
1198 | ||
1199 | sub doit | |
1200 | { | |
573a192d | 1201 | my $y; chop $y; |
33edcb80 RS |
1202 | } |
1203 | ||
1204 | doit(); | |
1205 | ||
1206 | { | |
1207 | local ($^W) = 1; | |
1208 | doit() | |
1209 | } | |
1210 | ||
1211 | This is a side-effect of C<$^W> being dynamically scoped. | |
1212 | ||
1213 | Lexical warnings get around these limitations by allowing finer control | |
1214 | over where warnings can or can't be tripped. | |
1215 | ||
1216 | =head2 Controlling Warnings from the Command Line | |
1217 | ||
1218 | There are three Command Line flags that can be used to control when | |
1219 | warnings are (or aren't) produced: | |
1220 | ||
1221 | =over 5 | |
1222 | ||
1223 | =item B<-w> | |
1224 | X<-w> | |
1225 | ||
1226 | This is the existing flag. If the lexical warnings pragma is B<not> | |
677f8b87 | 1227 | used in any of your code, or any of the modules that you use, this flag |
05a64c17 | 1228 | will enable warnings everywhere. See L</Backward Compatibility> for |
33edcb80 RS |
1229 | details of how this flag interacts with lexical warnings. |
1230 | ||
1231 | =item B<-W> | |
1232 | X<-W> | |
1233 | ||
3c3f8cd6 | 1234 | If the B<-W> flag is used on the command line, it will enable all warnings |
33edcb80 RS |
1235 | throughout the program regardless of whether warnings were disabled |
1236 | locally using C<no warnings> or C<$^W =0>. | |
1237 | This includes all files that get | |
1238 | included via C<use>, C<require> or C<do>. | |
1239 | Think of it as the Perl equivalent of the "lint" command. | |
1240 | ||
1241 | =item B<-X> | |
1242 | X<-X> | |
1243 | ||
3c3f8cd6 | 1244 | Does the exact opposite to the B<-W> flag, i.e. it disables all warnings. |
33edcb80 RS |
1245 | |
1246 | =back | |
1247 | ||
1248 | =head2 Backward Compatibility | |
1249 | ||
1250 | If you are used to working with a version of Perl prior to the | |
1251 | introduction of lexically scoped warnings, or have code that uses both | |
1252 | lexical warnings and C<$^W>, this section will describe how they interact. | |
1253 | ||
1254 | How Lexical Warnings interact with B<-w>/C<$^W>: | |
1255 | ||
1256 | =over 5 | |
1257 | ||
1258 | =item 1. | |
1259 | ||
1260 | If none of the three command line flags (B<-w>, B<-W> or B<-X>) that | |
1261 | control warnings is used and neither C<$^W> nor the C<warnings> pragma | |
1262 | are used, then default warnings will be enabled and optional warnings | |
1263 | disabled. | |
1264 | This means that legacy code that doesn't attempt to control the warnings | |
1265 | will work unchanged. | |
1266 | ||
1267 | =item 2. | |
1268 | ||
1269 | The B<-w> flag just sets the global C<$^W> variable as in 5.005. This | |
1270 | means that any legacy code that currently relies on manipulating C<$^W> | |
56873d42 | 1271 | to control warning behavior will still work as is. |
33edcb80 RS |
1272 | |
1273 | =item 3. | |
1274 | ||
1275 | Apart from now being a boolean, the C<$^W> variable operates in exactly | |
1276 | the same horrible uncontrolled global way, except that it cannot | |
1277 | disable/enable default warnings. | |
1278 | ||
1279 | =item 4. | |
1280 | ||
1281 | If a piece of code is under the control of the C<warnings> pragma, | |
1282 | both the C<$^W> variable and the B<-w> flag will be ignored for the | |
1283 | scope of the lexical warning. | |
1284 | ||
1285 | =item 5. | |
1286 | ||
1287 | The only way to override a lexical warnings setting is with the B<-W> | |
1288 | or B<-X> command line flags. | |
1289 | ||
1290 | =back | |
1291 | ||
1292 | The combined effect of 3 & 4 is that it will allow code which uses | |
1293 | the C<warnings> pragma to control the warning behavior of $^W-type | |
1294 | code (using a C<local $^W=0>) if it really wants to, but not vice-versa. | |
1295 | ||
1296 | =head2 Category Hierarchy | |
1297 | X<warning, categories> | |
1298 | ||
1299 | A hierarchy of "categories" have been defined to allow groups of warnings | |
1300 | to be enabled/disabled in isolation. | |
1301 | ||
1302 | The current hierarchy is: | |
1303 | ||
1304 | =for warnings.pl tree-goes-here | |
1305 | ||
1306 | Just like the "strict" pragma any of these categories can be combined | |
1307 | ||
1308 | use warnings qw(void redefine); | |
1309 | no warnings qw(io syntax untie); | |
1310 | ||
1311 | Also like the "strict" pragma, if there is more than one instance of the | |
56873d42 | 1312 | C<warnings> pragma in a given scope the cumulative effect is additive. |
33edcb80 RS |
1313 | |
1314 | use warnings qw(void); # only "void" warnings enabled | |
1315 | ... | |
1316 | use warnings qw(io); # only "void" & "io" warnings enabled | |
1317 | ... | |
1318 | no warnings qw(void); # only "io" warnings enabled | |
1319 | ||
1320 | To determine which category a specific warning has been assigned to see | |
1321 | L<perldiag>. | |
1322 | ||
1323 | Note: Before Perl 5.8.0, the lexical warnings category "deprecated" was a | |
1324 | sub-category of the "syntax" category. It is now a top-level category | |
1325 | in its own right. | |
1326 | ||
3664866e AB |
1327 | Note: Before 5.21.0, the "missing" lexical warnings category was |
1328 | internally defined to be the same as the "uninitialized" category. It | |
1329 | is now a top-level category in its own right. | |
1330 | ||
33edcb80 RS |
1331 | =head2 Fatal Warnings |
1332 | X<warning, fatal> | |
1333 | ||
2e4abf26 DG |
1334 | The presence of the word "FATAL" in the category list will escalate |
1335 | warnings in those categories into fatal errors in that lexical scope. | |
1336 | ||
1337 | B<NOTE:> FATAL warnings should be used with care, particularly | |
1338 | C<< FATAL => 'all' >>. | |
1339 | ||
1340 | Libraries using L<warnings::warn|/FUNCTIONS> for custom warning categories | |
1341 | generally don't expect L<warnings::warn|/FUNCTIONS> to be fatal and can wind up | |
1342 | in an unexpected state as a result. For XS modules issuing categorized | |
1343 | warnings, such unanticipated exceptions could also expose memory leak bugs. | |
1344 | ||
1345 | Moreover, the Perl interpreter itself has had serious bugs involving | |
1346 | fatalized warnings. For a summary of resolved and unresolved problems as | |
1347 | of January 2015, please see | |
1348 | L<this perl5-porters post|http://www.nntp.perl.org/group/perl.perl5.porters/2015/01/msg225235.html>. | |
1349 | ||
1350 | While some developers find fatalizing some warnings to be a useful | |
1351 | defensive programming technique, using C<< FATAL => 'all' >> to fatalize | |
1352 | all possible warning categories -- including custom ones -- is particularly | |
1353 | risky. Therefore, the use of C<< FATAL => 'all' >> is | |
1354 | L<discouraged|perlpolicy/discouraged>. | |
1355 | ||
1356 | The L<strictures|strictures/VERSION-2> module on CPAN offers one example of | |
1357 | a warnings subset that the module's authors believe is relatively safe to | |
1358 | fatalize. | |
1359 | ||
01900a5f | 1360 | B<NOTE:> Users of FATAL warnings, especially those using |
2e4abf26 DG |
1361 | C<< FATAL => 'all' >>, should be fully aware that they are risking future |
1362 | portability of their programs by doing so. Perl makes absolutely no | |
1363 | commitments to not introduce new warnings or warnings categories in the | |
1364 | future; indeed, we explicitly reserve the right to do so. Code that may | |
1365 | not warn now may warn in a future release of Perl if the Perl5 development | |
1366 | team deems it in the best interests of the community to do so. Should code | |
1367 | using FATAL warnings break due to the introduction of a new warning we will | |
1368 | NOT consider it an incompatible change. Users of FATAL warnings should | |
1369 | take special caution during upgrades to check to see if their code triggers | |
1370 | any new warnings and should pay particular attention to the fine print of | |
1371 | the documentation of the features they use to ensure they do not exploit | |
1372 | features that are documented as risky, deprecated, or unspecified, or where | |
1373 | the documentation says "so don't do that", or anything with the same sense | |
1374 | and spirit. Use of such features in combination with FATAL warnings is | |
1375 | ENTIRELY AT THE USER'S RISK. | |
1376 | ||
1377 | The following documentation describes how to use FATAL warnings but the | |
1378 | perl5 porters strongly recommend that you understand the risks before doing | |
1379 | so, especially for library code intended for use by others, as there is no | |
1380 | way for downstream users to change the choice of fatal categories. | |
1381 | ||
1382 | In the code below, the use of C<time>, C<length> | |
33edcb80 RS |
1383 | and C<join> can all produce a C<"Useless use of xxx in void context"> |
1384 | warning. | |
1385 | ||
1386 | use warnings; | |
1387 | ||
1388 | time; | |
1389 | ||
1390 | { | |
1391 | use warnings FATAL => qw(void); | |
1392 | length "abc"; | |
1393 | } | |
1394 | ||
1395 | join "", 1,2,3; | |
1396 | ||
1397 | print "done\n"; | |
1398 | ||
1399 | When run it produces this output | |
1400 | ||
1401 | Useless use of time in void context at fatal line 3. | |
56873d42 | 1402 | Useless use of length in void context at fatal line 7. |
33edcb80 RS |
1403 | |
1404 | The scope where C<length> is used has escalated the C<void> warnings | |
1405 | category into a fatal error, so the program terminates immediately when it | |
1406 | encounters the warning. | |
1407 | ||
1408 | To explicitly turn off a "FATAL" warning you just disable the warning | |
1409 | it is associated with. So, for example, to disable the "void" warning | |
1410 | in the example above, either of these will do the trick: | |
1411 | ||
1412 | no warnings qw(void); | |
1413 | no warnings FATAL => qw(void); | |
1414 | ||
1415 | If you want to downgrade a warning that has been escalated into a fatal | |
1416 | error back to a normal warning, you can use the "NONFATAL" keyword. For | |
1417 | example, the code below will promote all warnings into fatal errors, | |
1418 | except for those in the "syntax" category. | |
1419 | ||
1420 | use warnings FATAL => 'all', NONFATAL => 'syntax'; | |
1421 | ||
1422 | As of Perl 5.20, instead of C<< use warnings FATAL => 'all'; >> you can | |
1423 | use: | |
1424 | ||
1425 | use v5.20; # Perl 5.20 or greater is required for the following | |
1426 | use warnings 'FATAL'; # short form of "use warnings FATAL => 'all';" | |
1427 | ||
01900a5f | 1428 | However, you should still heed the guidance earlier in this section against |
5624cfff | 1429 | using C<< use warnings FATAL => 'all'; >>. |
01900a5f | 1430 | |
33edcb80 RS |
1431 | If you want your program to be compatible with versions of Perl before |
1432 | 5.20, you must use C<< use warnings FATAL => 'all'; >> instead. (In | |
1433 | previous versions of Perl, the behavior of the statements | |
1434 | C<< use warnings 'FATAL'; >>, C<< use warnings 'NONFATAL'; >> and | |
1435 | C<< no warnings 'FATAL'; >> was unspecified; they did not behave as if | |
1436 | they included the C<< => 'all' >> portion. As of 5.20, they do.) | |
1437 | ||
33edcb80 RS |
1438 | =head2 Reporting Warnings from a Module |
1439 | X<warning, reporting> X<warning, registering> | |
1440 | ||
1441 | The C<warnings> pragma provides a number of functions that are useful for | |
1442 | module authors. These are used when you want to report a module-specific | |
78d7b3d6 | 1443 | warning to a calling module that has enabled warnings via the C<warnings> |
33edcb80 RS |
1444 | pragma. |
1445 | ||
1446 | Consider the module C<MyMod::Abc> below. | |
1447 | ||
1448 | package MyMod::Abc; | |
1449 | ||
1450 | use warnings::register; | |
1451 | ||
1452 | sub open { | |
1453 | my $path = shift; | |
1454 | if ($path !~ m#^/#) { | |
1455 | warnings::warn("changing relative path to /var/abc") | |
1456 | if warnings::enabled(); | |
1457 | $path = "/var/abc/$path"; | |
1458 | } | |
1459 | } | |
1460 | ||
1461 | 1; | |
1462 | ||
1463 | The call to C<warnings::register> will create a new warnings category | |
1464 | called "MyMod::Abc", i.e. the new category name matches the current | |
1465 | package name. The C<open> function in the module will display a warning | |
78d7b3d6 | 1466 | message if it gets given a relative path as a parameter. This warning |
33edcb80 | 1467 | will only be displayed if the code that uses C<MyMod::Abc> has actually |
78d7b3d6 HS |
1468 | enabled them with the C<warnings> pragma as below - note that a plain |
1469 | C<use warnings> enables even warnings that have not yet been registered. | |
33edcb80 | 1470 | |
78d7b3d6 | 1471 | use warnings; |
33edcb80 | 1472 | use MyMod::Abc; |
78d7b3d6 HS |
1473 | ... |
1474 | abc::open("../fred.txt"); | |
1475 | ||
1476 | The specific warning can be enabled or disabled, but only after the module | |
1477 | has been imported: | |
1478 | ||
1479 | # no warnings 'MyMod::Abc'; # error, unknown category before | |
1480 | # the module is loaded | |
1481 | use MyMod::Abc; | |
1482 | no warnings 'MyMod::Abc'; # ok after the module is loaded | |
33edcb80 RS |
1483 | ... |
1484 | abc::open("../fred.txt"); | |
1485 | ||
1486 | It is also possible to test whether the pre-defined warnings categories are | |
1487 | set in the calling module with the C<warnings::enabled> function. Consider | |
1488 | this snippet of code: | |
1489 | ||
1490 | package MyMod::Abc; | |
1491 | ||
78d7b3d6 | 1492 | sub open2 { |
4a21999a TC |
1493 | if (warnings::enabled("deprecated")) { |
1494 | warnings::warn("deprecated", | |
78d7b3d6 | 1495 | "open2 is deprecated, use open instead"); |
4a21999a | 1496 | } |
78d7b3d6 | 1497 | open(@_); |
33edcb80 RS |
1498 | } |
1499 | ||
0a92f341 | 1500 | sub open |
33edcb80 RS |
1501 | ... |
1502 | 1; | |
1503 | ||
78d7b3d6 | 1504 | The function C<open2> has been deprecated, so code has been included to |
33edcb80 RS |
1505 | display a warning message whenever the calling module has (at least) the |
1506 | "deprecated" warnings category enabled. Something like this, say. | |
1507 | ||
1508 | use warnings 'deprecated'; | |
1509 | use MyMod::Abc; | |
1510 | ... | |
78d7b3d6 | 1511 | MyMod::Abc::open2($filename); |
33edcb80 RS |
1512 | |
1513 | Either the C<warnings::warn> or C<warnings::warnif> function should be | |
1514 | used to actually display the warnings message. This is because they can | |
1515 | make use of the feature that allows warnings to be escalated into fatal | |
1516 | errors. So in this case | |
1517 | ||
1518 | use MyMod::Abc; | |
1519 | use warnings FATAL => 'MyMod::Abc'; | |
1520 | ... | |
1521 | MyMod::Abc::open('../fred.txt'); | |
1522 | ||
1523 | the C<warnings::warnif> function will detect this and die after | |
1524 | displaying the warning message. | |
1525 | ||
1526 | The three warnings functions, C<warnings::warn>, C<warnings::warnif> | |
1527 | and C<warnings::enabled> can optionally take an object reference in place | |
1528 | of a category name. In this case the functions will use the class name | |
1529 | of the object as the warnings category. | |
1530 | ||
1531 | Consider this example: | |
1532 | ||
1533 | package Original; | |
1534 | ||
1535 | no warnings; | |
1536 | use warnings::register; | |
1537 | ||
1538 | sub new | |
1539 | { | |
1540 | my $class = shift; | |
1541 | bless [], $class; | |
1542 | } | |
1543 | ||
1544 | sub check | |
1545 | { | |
1546 | my $self = shift; | |
1547 | my $value = shift; | |
1548 | ||
1549 | if ($value % 2 && warnings::enabled($self)) | |
1550 | { warnings::warn($self, "Odd numbers are unsafe") } | |
1551 | } | |
1552 | ||
1553 | sub doit | |
1554 | { | |
1555 | my $self = shift; | |
1556 | my $value = shift; | |
1557 | $self->check($value); | |
1558 | # ... | |
1559 | } | |
1560 | ||
1561 | 1; | |
1562 | ||
1563 | package Derived; | |
1564 | ||
1565 | use warnings::register; | |
1566 | use Original; | |
1567 | our @ISA = qw( Original ); | |
1568 | sub new | |
1569 | { | |
1570 | my $class = shift; | |
1571 | bless [], $class; | |
1572 | } | |
1573 | ||
1574 | ||
1575 | 1; | |
1576 | ||
56873d42 | 1577 | The code below makes use of both modules, but it only enables warnings from |
33edcb80 RS |
1578 | C<Derived>. |
1579 | ||
1580 | use Original; | |
1581 | use Derived; | |
1582 | use warnings 'Derived'; | |
573a192d DIM |
1583 | my $x = Original->new(); |
1584 | $x->doit(1); | |
1585 | my $y = Derived->new(); | |
1586 | $x->doit(1); | |
33edcb80 | 1587 | |
573a192d | 1588 | When this code is run only the C<Derived> object, C<$y>, will generate |
56873d42 | 1589 | a warning. |
33edcb80 RS |
1590 | |
1591 | Odd numbers are unsafe at main.pl line 7 | |
1592 | ||
1593 | Notice also that the warning is reported at the line where the object is first | |
1594 | used. | |
1595 | ||
1596 | When registering new categories of warning, you can supply more names to | |
1597 | warnings::register like this: | |
1598 | ||
1599 | package MyModule; | |
1600 | use warnings::register qw(format precision); | |
1601 | ||
1602 | ... | |
fe2e802c | 1603 | |
33edcb80 | 1604 | warnings::warnif('MyModule::format', '...'); |
599cee73 | 1605 | |
33edcb80 | 1606 | =head1 FUNCTIONS |
e476b1b5 | 1607 | |
c4583f59 FC |
1608 | Note: The functions with names ending in C<_at_level> were added in Perl |
1609 | 5.28. | |
1610 | ||
39b50539 Z |
1611 | =over 4 |
1612 | ||
d3a7d8c7 GS |
1613 | =item use warnings::register |
1614 | ||
7e6d00f8 PM |
1615 | Creates a new warnings category with the same name as the package where |
1616 | the call to the pragma is used. | |
1617 | ||
1618 | =item warnings::enabled() | |
1619 | ||
1620 | Use the warnings category with the same name as the current package. | |
1621 | ||
1622 | Return TRUE if that warnings category is enabled in the calling module. | |
1623 | Otherwise returns FALSE. | |
1624 | ||
1625 | =item warnings::enabled($category) | |
1626 | ||
1627 | Return TRUE if the warnings category, C<$category>, is enabled in the | |
1628 | calling module. | |
1629 | Otherwise returns FALSE. | |
1630 | ||
1631 | =item warnings::enabled($object) | |
1632 | ||
1633 | Use the name of the class for the object reference, C<$object>, as the | |
1634 | warnings category. | |
1635 | ||
1636 | Return TRUE if that warnings category is enabled in the first scope | |
1637 | where the object is used. | |
1638 | Otherwise returns FALSE. | |
1639 | ||
c4583f59 FC |
1640 | =item warnings::enabled_at_level($category, $level) |
1641 | ||
1642 | Like C<warnings::enabled>, but $level specifies the exact call frame, 0 | |
1643 | being the immediate caller. | |
1644 | ||
ec983580 AR |
1645 | =item warnings::fatal_enabled() |
1646 | ||
1647 | Return TRUE if the warnings category with the same name as the current | |
1648 | package has been set to FATAL in the calling module. | |
1649 | Otherwise returns FALSE. | |
1650 | ||
1651 | =item warnings::fatal_enabled($category) | |
1652 | ||
1653 | Return TRUE if the warnings category C<$category> has been set to FATAL in | |
1654 | the calling module. | |
1655 | Otherwise returns FALSE. | |
1656 | ||
1657 | =item warnings::fatal_enabled($object) | |
1658 | ||
1659 | Use the name of the class for the object reference, C<$object>, as the | |
1660 | warnings category. | |
1661 | ||
1662 | Return TRUE if that warnings category has been set to FATAL in the first | |
1663 | scope where the object is used. | |
1664 | Otherwise returns FALSE. | |
1665 | ||
c4583f59 FC |
1666 | =item warnings::fatal_enabled_at_level($category, $level) |
1667 | ||
1668 | Like C<warnings::fatal_enabled>, but $level specifies the exact call frame, | |
1669 | 0 being the immediate caller. | |
1670 | ||
7e6d00f8 PM |
1671 | =item warnings::warn($message) |
1672 | ||
1673 | Print C<$message> to STDERR. | |
1674 | ||
1675 | Use the warnings category with the same name as the current package. | |
1676 | ||
1677 | If that warnings category has been set to "FATAL" in the calling module | |
1678 | then die. Otherwise return. | |
1679 | ||
1680 | =item warnings::warn($category, $message) | |
1681 | ||
1682 | Print C<$message> to STDERR. | |
1683 | ||
1684 | If the warnings category, C<$category>, has been set to "FATAL" in the | |
1685 | calling module then die. Otherwise return. | |
d3a7d8c7 | 1686 | |
7e6d00f8 | 1687 | =item warnings::warn($object, $message) |
e476b1b5 | 1688 | |
7e6d00f8 | 1689 | Print C<$message> to STDERR. |
e476b1b5 | 1690 | |
7e6d00f8 PM |
1691 | Use the name of the class for the object reference, C<$object>, as the |
1692 | warnings category. | |
e476b1b5 | 1693 | |
7e6d00f8 PM |
1694 | If that warnings category has been set to "FATAL" in the scope where C<$object> |
1695 | is first used then die. Otherwise return. | |
599cee73 | 1696 | |
c4583f59 FC |
1697 | =item warnings::warn_at_level($category, $level, $message) |
1698 | ||
1699 | Like C<warnings::warn>, but $level specifies the exact call frame, | |
1700 | 0 being the immediate caller. | |
e476b1b5 | 1701 | |
7e6d00f8 PM |
1702 | =item warnings::warnif($message) |
1703 | ||
1704 | Equivalent to: | |
1705 | ||
1706 | if (warnings::enabled()) | |
1707 | { warnings::warn($message) } | |
1708 | ||
1709 | =item warnings::warnif($category, $message) | |
1710 | ||
1711 | Equivalent to: | |
1712 | ||
1713 | if (warnings::enabled($category)) | |
1714 | { warnings::warn($category, $message) } | |
1715 | ||
1716 | =item warnings::warnif($object, $message) | |
1717 | ||
1718 | Equivalent to: | |
1719 | ||
1720 | if (warnings::enabled($object)) | |
1721 | { warnings::warn($object, $message) } | |
d3a7d8c7 | 1722 | |
c4583f59 FC |
1723 | =item warnings::warnif_at_level($category, $level, $message) |
1724 | ||
1725 | Like C<warnings::warnif>, but $level specifies the exact call frame, | |
1726 | 0 being the immediate caller. | |
1727 | ||
5e7ad92a | 1728 | =item warnings::register_categories(@names) |
13781810 FR |
1729 | |
1730 | This registers warning categories for the given names and is primarily for | |
d2ec25a5 | 1731 | use by the warnings::register pragma. |
13781810 | 1732 | |
e476b1b5 GS |
1733 | =back |
1734 | ||
d2ec25a5 | 1735 | See also L<perlmodlib/Pragmatic Modules> and L<perldiag>. |
599cee73 PM |
1736 | |
1737 | =cut |