3 * Copyright (C) 2012 by Larry Wall and others
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
8 * This file contains tables and code adapted from
9 * https://bjoern.hoehrmann.de/utf-8/decoder/dfa/, which requires this
12 Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
14 Permission is hereby granted, free of charge, to any person obtaining a copy of
15 this software and associated documentation files (the "Software"), to deal in
16 the Software without restriction, including without limitation the rights to
17 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
18 of the Software, and to permit persons to whom the Software is furnished to do
19 so, subject to the following conditions:
21 The above copyright notice and this permission notice shall be included in all
22 copies or substantial portions of the Software.
24 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
27 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
28 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
29 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33 * This file is a home for static inline functions that cannot go in other
34 * header files, because they depend on proto.h (included after most other
35 * headers) or struct definitions.
37 * Each section names the header file that the functions "belong" to.
40 /* ------------------------------- av.h ------------------------------- */
43 =for apidoc_section $AV
45 Returns the number of elements in the array C<av>. This is the true length of
46 the array, including any undefined elements. It is always the same as
47 S<C<av_top_index(av) + 1>>.
51 PERL_STATIC_INLINE Size_t
52 Perl_av_count(pTHX_ AV *av)
54 PERL_ARGS_ASSERT_AV_COUNT;
55 assert(SvTYPE(av) == SVt_PVAV);
57 return AvFILL(av) + 1;
60 /* ------------------------------- av.c ------------------------------- */
63 =for apidoc av_store_simple
65 This is a cut-down version of av_store that assumes that the array is
66 very straightforward - no magic, not readonly, and AvREAL - and that
67 C<key> is not negative. This function MUST NOT be used in situations
68 where any of those assumptions may not hold.
70 Stores an SV in an array. The array index is specified as C<key>. It
71 can be dereferenced to get the C<SV*> that was stored there (= C<val>)).
73 Note that the caller is responsible for suitably incrementing the reference
74 count of C<val> before the call.
76 Approximate Perl equivalent: C<splice(@myarray, $key, 1, $val)>.
81 PERL_STATIC_INLINE SV**
82 Perl_av_store_simple(pTHX_ AV *av, SSize_t key, SV *val)
86 PERL_ARGS_ASSERT_AV_STORE_SIMPLE;
87 assert(SvTYPE(av) == SVt_PVAV);
88 assert(!SvMAGICAL(av));
89 assert(!SvREADONLY(av));
95 if (AvFILLp(av) < key) {
96 if (key > AvMAX(av)) {
102 SvREFCNT_dec(ary[key]);
109 =for apidoc av_fetch_simple
111 This is a cut-down version of av_fetch that assumes that the array is
112 very straightforward - no magic, not readonly, and AvREAL - and that
113 C<key> is not negative. This function MUST NOT be used in situations
114 where any of those assumptions may not hold.
116 Returns the SV at the specified index in the array. The C<key> is the
117 index. If lval is true, you are guaranteed to get a real SV back (in case
118 it wasn't real before), which you can then modify. Check that the return
119 value is non-null before dereferencing it to a C<SV*>.
121 The rough perl equivalent is C<$myarray[$key]>.
126 PERL_STATIC_INLINE SV**
127 Perl_av_fetch_simple(pTHX_ AV *av, SSize_t key, I32 lval)
129 PERL_ARGS_ASSERT_AV_FETCH_SIMPLE;
130 assert(SvTYPE(av) == SVt_PVAV);
131 assert(!SvMAGICAL(av));
132 assert(!SvREADONLY(av));
136 if ( (key > AvFILLp(av)) || !AvARRAY(av)[key]) {
137 return lval ? av_store_simple(av,key,newSV(0)) : NULL;
139 return &AvARRAY(av)[key];
143 /* ------------------------------- cv.h ------------------------------- */
146 =for apidoc_section $CV
148 Returns the GV associated with the CV C<sv>, reifying it if necessary.
152 PERL_STATIC_INLINE GV *
153 Perl_CvGV(pTHX_ CV *sv)
155 PERL_ARGS_ASSERT_CVGV;
158 ? Perl_cvgv_from_hek(aTHX_ sv)
159 : ((XPVCV*)MUTABLE_PTR(SvANY(sv)))->xcv_gv_u.xcv_gv;
162 PERL_STATIC_INLINE I32 *
163 Perl_CvDEPTH(const CV * const sv)
165 PERL_ARGS_ASSERT_CVDEPTH;
166 assert(SvTYPE(sv) == SVt_PVCV || SvTYPE(sv) == SVt_PVFM);
168 return &((XPVCV*)SvANY(sv))->xcv_depth;
172 CvPROTO returns the prototype as stored, which is not necessarily what
173 the interpreter should be using. Specifically, the interpreter assumes
174 that spaces have been stripped, which has been the case if the prototype
175 was added by toke.c, but is generally not the case if it was added elsewhere.
176 Since we can't enforce the spacelessness at assignment time, this routine
177 provides a temporary copy at parse time with spaces removed.
178 I<orig> is the start of the original buffer, I<len> is the length of the
179 prototype and will be updated when this returns.
183 PERL_STATIC_INLINE char *
184 S_strip_spaces(pTHX_ const char * orig, STRLEN * const len)
188 tmpsv = newSVpvn_flags(orig, *len, SVs_TEMP);
196 *len = tmps - SvPVX(tmpsv);
201 /* ------------------------------- mg.h ------------------------------- */
203 #if defined(PERL_CORE) || defined(PERL_EXT)
204 /* assumes get-magic and stringification have already occurred */
205 PERL_STATIC_INLINE STRLEN
206 S_MgBYTEPOS(pTHX_ MAGIC *mg, SV *sv, const char *s, STRLEN len)
208 assert(mg->mg_type == PERL_MAGIC_regex_global);
209 assert(mg->mg_len != -1);
210 if (mg->mg_flags & MGf_BYTES || !DO_UTF8(sv))
211 return (STRLEN)mg->mg_len;
213 const STRLEN pos = (STRLEN)mg->mg_len;
214 /* Without this check, we may read past the end of the buffer: */
215 if (pos > sv_or_pv_len_utf8(sv, s, len)) return len+1;
216 return sv_or_pv_pos_u2b(sv, s, pos, NULL);
221 /* ------------------------------- pad.h ------------------------------ */
223 #if defined(PERL_IN_PAD_C) || defined(PERL_IN_OP_C)
224 PERL_STATIC_INLINE bool
225 S_PadnameIN_SCOPE(const PADNAME * const pn, const U32 seq)
227 PERL_ARGS_ASSERT_PADNAMEIN_SCOPE;
229 /* is seq within the range _LOW to _HIGH ?
230 * This is complicated by the fact that PL_cop_seqmax
231 * may have wrapped around at some point */
232 if (COP_SEQ_RANGE_LOW(pn) == PERL_PADSEQ_INTRO)
233 return FALSE; /* not yet introduced */
235 if (COP_SEQ_RANGE_HIGH(pn) == PERL_PADSEQ_INTRO) {
236 /* in compiling scope */
238 (seq > COP_SEQ_RANGE_LOW(pn))
239 ? (seq - COP_SEQ_RANGE_LOW(pn) < (U32_MAX >> 1))
240 : (COP_SEQ_RANGE_LOW(pn) - seq > (U32_MAX >> 1))
245 (COP_SEQ_RANGE_LOW(pn) > COP_SEQ_RANGE_HIGH(pn))
247 ( seq > COP_SEQ_RANGE_LOW(pn)
248 || seq <= COP_SEQ_RANGE_HIGH(pn))
250 : ( seq > COP_SEQ_RANGE_LOW(pn)
251 && seq <= COP_SEQ_RANGE_HIGH(pn))
258 /* ------------------------------- pp.h ------------------------------- */
260 PERL_STATIC_INLINE I32
263 DEBUG_s(DEBUG_v(PerlIO_printf(Perl_debug_log,
264 "MARK top %p %" IVdf "\n",
266 (IV)*PL_markstack_ptr)));
267 return *PL_markstack_ptr;
270 PERL_STATIC_INLINE I32
273 DEBUG_s(DEBUG_v(PerlIO_printf(Perl_debug_log,
274 "MARK pop %p %" IVdf "\n",
275 (PL_markstack_ptr-1),
276 (IV)*(PL_markstack_ptr-1))));
277 assert((PL_markstack_ptr > PL_markstack) || !"MARK underflow");
278 return *PL_markstack_ptr--;
281 /* ----------------------------- regexp.h ----------------------------- */
283 /* PVLVs need to act as a superset of all scalar types - they are basically
284 * PVMGs with a few extra fields.
285 * REGEXPs are first class scalars, but have many fields that can't be copied
288 * Hence we take a different approach - instead of a copy, PVLVs store a pointer
289 * back to the original body. To avoid increasing the size of PVLVs just for the
290 * rare case of REGEXP assignment, this pointer is stored in the memory usually
291 * used for SvLEN(). Hence the check for SVt_PVLV below, and the ? : ternary to
292 * read the pointer from the two possible locations. The macro SvLEN() wraps the
293 * access to the union's member xpvlenu_len, but there is no equivalent macro
294 * for wrapping the union's member xpvlenu_rx, hence the direct reference here.
296 * See commit df6b4bd56551f2d3 for more details. */
298 PERL_STATIC_INLINE struct regexp *
299 Perl_ReANY(const REGEXP * const re)
301 XPV* const p = (XPV*)SvANY(re);
303 PERL_ARGS_ASSERT_REANY;
304 assert(isREGEXP(re));
306 return SvTYPE(re) == SVt_PVLV ? p->xpv_len_u.xpvlenu_rx
307 : (struct regexp *)p;
310 /* ------------------------------- sv.h ------------------------------- */
312 PERL_STATIC_INLINE bool
313 Perl_SvTRUE(pTHX_ SV *sv)
315 PERL_ARGS_ASSERT_SVTRUE;
317 if (UNLIKELY(sv == NULL))
320 return SvTRUE_nomg_NN(sv);
323 PERL_STATIC_INLINE bool
324 Perl_SvTRUE_nomg(pTHX_ SV *sv)
326 PERL_ARGS_ASSERT_SVTRUE_NOMG;
328 if (UNLIKELY(sv == NULL))
330 return SvTRUE_nomg_NN(sv);
333 PERL_STATIC_INLINE bool
334 Perl_SvTRUE_NN(pTHX_ SV *sv)
336 PERL_ARGS_ASSERT_SVTRUE_NN;
339 return SvTRUE_nomg_NN(sv);
342 PERL_STATIC_INLINE bool
343 Perl_SvTRUE_common(pTHX_ SV * sv, const bool sv_2bool_is_fallback)
345 PERL_ARGS_ASSERT_SVTRUE_COMMON;
347 if (UNLIKELY(SvIMMORTAL_INTERP(sv)))
348 return SvIMMORTAL_TRUE(sv);
354 return SvPVXtrue(sv);
357 return SvIVX(sv) != 0; /* casts to bool */
359 if (SvROK(sv) && !(SvOBJECT(SvRV(sv)) && HvAMAGIC(SvSTASH(SvRV(sv)))))
362 if (sv_2bool_is_fallback)
363 return sv_2bool_nomg(sv);
365 return isGV_with_GP(sv);
369 PERL_STATIC_INLINE SV *
370 Perl_SvREFCNT_inc(SV *sv)
372 if (LIKELY(sv != NULL))
376 PERL_STATIC_INLINE SV *
377 Perl_SvREFCNT_inc_NN(SV *sv)
379 PERL_ARGS_ASSERT_SVREFCNT_INC_NN;
384 PERL_STATIC_INLINE void
385 Perl_SvREFCNT_inc_void(SV *sv)
387 if (LIKELY(sv != NULL))
390 PERL_STATIC_INLINE void
391 Perl_SvREFCNT_dec(pTHX_ SV *sv)
393 if (LIKELY(sv != NULL)) {
394 U32 rc = SvREFCNT(sv);
396 SvREFCNT(sv) = rc - 1;
398 Perl_sv_free2(aTHX_ sv, rc);
402 PERL_STATIC_INLINE void
403 Perl_SvREFCNT_dec_NN(pTHX_ SV *sv)
405 U32 rc = SvREFCNT(sv);
407 PERL_ARGS_ASSERT_SVREFCNT_DEC_NN;
410 SvREFCNT(sv) = rc - 1;
412 Perl_sv_free2(aTHX_ sv, rc);
415 PERL_STATIC_INLINE void
416 Perl_SvAMAGIC_on(SV *sv)
418 PERL_ARGS_ASSERT_SVAMAGIC_ON;
421 if (SvOBJECT(SvRV(sv))) HvAMAGIC_on(SvSTASH(SvRV(sv)));
423 PERL_STATIC_INLINE void
424 Perl_SvAMAGIC_off(SV *sv)
426 PERL_ARGS_ASSERT_SVAMAGIC_OFF;
428 if (SvROK(sv) && SvOBJECT(SvRV(sv)))
429 HvAMAGIC_off(SvSTASH(SvRV(sv)));
432 PERL_STATIC_INLINE U32
433 Perl_SvPADSTALE_on(SV *sv)
435 assert(!(SvFLAGS(sv) & SVs_PADTMP));
436 return SvFLAGS(sv) |= SVs_PADSTALE;
438 PERL_STATIC_INLINE U32
439 Perl_SvPADSTALE_off(SV *sv)
441 assert(!(SvFLAGS(sv) & SVs_PADTMP));
442 return SvFLAGS(sv) &= ~SVs_PADSTALE;
444 #if defined(PERL_CORE) || defined (PERL_EXT)
445 PERL_STATIC_INLINE STRLEN
446 S_sv_or_pv_pos_u2b(pTHX_ SV *sv, const char *pv, STRLEN pos, STRLEN *lenp)
448 PERL_ARGS_ASSERT_SV_OR_PV_POS_U2B;
450 U8 *hopped = utf8_hop((U8 *)pv, pos);
451 if (lenp) *lenp = (STRLEN)(utf8_hop(hopped, *lenp) - hopped);
452 return (STRLEN)(hopped - (U8 *)pv);
454 return sv_pos_u2b_flags(sv,pos,lenp,SV_CONST_RETURN);
458 /* ------------------------------- utf8.h ------------------------------- */
461 =for apidoc_section $unicode
464 PERL_STATIC_INLINE void
465 Perl_append_utf8_from_native_byte(const U8 byte, U8** dest)
467 /* Takes an input 'byte' (Latin1 or EBCDIC) and appends it to the UTF-8
468 * encoded string at '*dest', updating '*dest' to include it */
470 PERL_ARGS_ASSERT_APPEND_UTF8_FROM_NATIVE_BYTE;
472 if (NATIVE_BYTE_IS_INVARIANT(byte))
475 *((*dest)++) = UTF8_EIGHT_BIT_HI(byte);
476 *((*dest)++) = UTF8_EIGHT_BIT_LO(byte);
481 =for apidoc valid_utf8_to_uvchr
482 Like C<L<perlapi/utf8_to_uvchr_buf>>, but should only be called when it is
483 known that the next character in the input UTF-8 string C<s> is well-formed
484 (I<e.g.>, it passes C<L<perlapi/isUTF8_CHAR>>. Surrogates, non-character code
485 points, and non-Unicode code points are allowed.
491 PERL_STATIC_INLINE UV
492 Perl_valid_utf8_to_uvchr(const U8 *s, STRLEN *retlen)
494 const UV expectlen = UTF8SKIP(s);
495 const U8* send = s + expectlen;
498 PERL_ARGS_ASSERT_VALID_UTF8_TO_UVCHR;
504 /* An invariant is trivially returned */
505 if (expectlen == 1) {
509 /* Remove the leading bits that indicate the number of bytes, leaving just
510 * the bits that are part of the value */
511 uv = NATIVE_UTF8_TO_I8(uv) & UTF_START_MASK(expectlen);
513 /* Now, loop through the remaining bytes, accumulating each into the
514 * working total as we go. (I khw tried unrolling the loop for up to 4
515 * bytes, but there was no performance improvement) */
516 for (++s; s < send; s++) {
517 uv = UTF8_ACCUMULATE(uv, *s);
520 return UNI_TO_NATIVE(uv);
525 =for apidoc is_utf8_invariant_string
527 Returns TRUE if the first C<len> bytes of the string C<s> are the same
528 regardless of the UTF-8 encoding of the string (or UTF-EBCDIC encoding on
529 EBCDIC machines); otherwise it returns FALSE. That is, it returns TRUE if they
530 are UTF-8 invariant. On ASCII-ish machines, all the ASCII characters and only
531 the ASCII characters fit this definition. On EBCDIC machines, the ASCII-range
532 characters are invariant, but so also are the C1 controls.
534 If C<len> is 0, it will be calculated using C<strlen(s)>, (which means if you
535 use this option, that C<s> can't have embedded C<NUL> characters and has to
536 have a terminating C<NUL> byte).
539 C<L</is_utf8_string>>,
540 C<L</is_utf8_string_flags>>,
541 C<L</is_utf8_string_loc>>,
542 C<L</is_utf8_string_loc_flags>>,
543 C<L</is_utf8_string_loclen>>,
544 C<L</is_utf8_string_loclen_flags>>,
545 C<L</is_utf8_fixed_width_buf_flags>>,
546 C<L</is_utf8_fixed_width_buf_loc_flags>>,
547 C<L</is_utf8_fixed_width_buf_loclen_flags>>,
548 C<L</is_strict_utf8_string>>,
549 C<L</is_strict_utf8_string_loc>>,
550 C<L</is_strict_utf8_string_loclen>>,
551 C<L</is_c9strict_utf8_string>>,
552 C<L</is_c9strict_utf8_string_loc>>,
554 C<L</is_c9strict_utf8_string_loclen>>.
560 #define is_utf8_invariant_string(s, len) \
561 is_utf8_invariant_string_loc(s, len, NULL)
564 =for apidoc is_utf8_invariant_string_loc
566 Like C<L</is_utf8_invariant_string>> but upon failure, stores the location of
567 the first UTF-8 variant character in the C<ep> pointer; if all characters are
568 UTF-8 invariant, this function does not change the contents of C<*ep>.
574 PERL_STATIC_INLINE bool
575 Perl_is_utf8_invariant_string_loc(const U8* const s, STRLEN len, const U8 ** ep)
580 PERL_ARGS_ASSERT_IS_UTF8_INVARIANT_STRING_LOC;
583 len = strlen((const char *)s);
588 /* This looks like 0x010101... */
589 # define PERL_COUNT_MULTIPLIER (~ (UINTMAX_C(0)) / 0xFF)
591 /* This looks like 0x808080... */
592 # define PERL_VARIANTS_WORD_MASK (PERL_COUNT_MULTIPLIER * 0x80)
593 # define PERL_WORDSIZE sizeof(PERL_UINTMAX_T)
594 # define PERL_WORD_BOUNDARY_MASK (PERL_WORDSIZE - 1)
596 /* Evaluates to 0 if 'x' is at a word boundary; otherwise evaluates to 1, by
597 * or'ing together the lowest bits of 'x'. Hopefully the final term gets
598 * optimized out completely on a 32-bit system, and its mask gets optimized out
599 * on a 64-bit system */
600 # define PERL_IS_SUBWORD_ADDR(x) (1 & ( PTR2nat(x) \
601 | ( PTR2nat(x) >> 1) \
603 & PERL_WORD_BOUNDARY_MASK) >> 2))))
607 /* Do the word-at-a-time iff there is at least one usable full word. That
608 * means that after advancing to a word boundary, there still is at least a
609 * full word left. The number of bytes needed to advance is 'wordsize -
610 * offset' unless offset is 0. */
611 if ((STRLEN) (send - x) >= PERL_WORDSIZE
613 /* This term is wordsize if subword; 0 if not */
614 + PERL_WORDSIZE * PERL_IS_SUBWORD_ADDR(x)
617 - (PTR2nat(x) & PERL_WORD_BOUNDARY_MASK))
620 /* Process per-byte until reach word boundary. XXX This loop could be
621 * eliminated if we knew that this platform had fast unaligned reads */
622 while (PTR2nat(x) & PERL_WORD_BOUNDARY_MASK) {
623 if (! UTF8_IS_INVARIANT(*x)) {
633 /* Here, we know we have at least one full word to process. Process
634 * per-word as long as we have at least a full word left */
636 if ((* (PERL_UINTMAX_T *) x) & PERL_VARIANTS_WORD_MASK) {
638 /* Found a variant. Just return if caller doesn't want its
644 # if BYTEORDER == 0x1234 || BYTEORDER == 0x12345678 \
645 || BYTEORDER == 0x4321 || BYTEORDER == 0x87654321
647 *ep = x + variant_byte_number(* (PERL_UINTMAX_T *) x);
648 assert(*ep >= s && *ep < send);
652 # else /* If weird byte order, drop into next loop to do byte-at-a-time
661 } while (x + PERL_WORDSIZE <= send);
664 #endif /* End of ! EBCDIC */
666 /* Process per-byte */
668 if (! UTF8_IS_INVARIANT(*x)) {
682 /* See if the platform has builtins for finding the most/least significant bit,
683 * and which one is right for using on 32 and 64 bit operands */
684 #if (__has_builtin(__builtin_clz) || PERL_GCC_VERSION_GE(3,4,0))
685 # if U32SIZE == INTSIZE
686 # define PERL_CLZ_32 __builtin_clz
688 # if defined(U64TYPE) && U64SIZE == INTSIZE
689 # define PERL_CLZ_64 __builtin_clz
692 #if (__has_builtin(__builtin_ctz) || PERL_GCC_VERSION_GE(3,4,0))
693 # if U32SIZE == INTSIZE
694 # define PERL_CTZ_32 __builtin_ctz
696 # if defined(U64TYPE) && U64SIZE == INTSIZE
697 # define PERL_CTZ_64 __builtin_ctz
701 #if (__has_builtin(__builtin_clzl) || PERL_GCC_VERSION_GE(3,4,0))
702 # if U32SIZE == LONGSIZE && ! defined(PERL_CLZ_32)
703 # define PERL_CLZ_32 __builtin_clzl
705 # if defined(U64TYPE) && U64SIZE == LONGSIZE && ! defined(PERL_CLZ_64)
706 # define PERL_CLZ_64 __builtin_clzl
709 #if (__has_builtin(__builtin_ctzl) || PERL_GCC_VERSION_GE(3,4,0))
710 # if U32SIZE == LONGSIZE && ! defined(PERL_CTZ_32)
711 # define PERL_CTZ_32 __builtin_ctzl
713 # if defined(U64TYPE) && U64SIZE == LONGSIZE && ! defined(PERL_CTZ_64)
714 # define PERL_CTZ_64 __builtin_ctzl
718 #if (__has_builtin(__builtin_clzll) || PERL_GCC_VERSION_GE(3,4,0))
719 # if U32SIZE == LONGLONGSIZE && ! defined(PERL_CLZ_32)
720 # define PERL_CLZ_32 __builtin_clzll
722 # if defined(U64TYPE) && U64SIZE == LONGLONGSIZE && ! defined(PERL_CLZ_64)
723 # define PERL_CLZ_64 __builtin_clzll
726 #if (__has_builtin(__builtin_ctzll) || PERL_GCC_VERSION_GE(3,4,0))
727 # if U32SIZE == LONGLONGSIZE && ! defined(PERL_CTZ_32)
728 # define PERL_CTZ_32 __builtin_ctzll
730 # if defined(U64TYPE) && U64SIZE == LONGLONGSIZE && ! defined(PERL_CTZ_64)
731 # define PERL_CTZ_64 __builtin_ctzll
735 #if defined(_MSC_VER)
737 # pragma intrinsic(_BitScanForward)
738 # pragma intrinsic(_BitScanReverse)
740 # pragma intrinsic(_BitScanForward64)
741 # pragma intrinsic(_BitScanReverse64)
745 /* The reason there are not checks to see if ffs() and ffsl() are available for
746 * determining the lsb, is because these don't improve on the deBruijn method
747 * fallback, which is just a branchless integer multiply, array element
748 * retrieval, and shift. The others, even if the function call overhead is
749 * optimized out, have to cope with the possibility of the input being all
750 * zeroes, and almost certainly will have conditionals for this eventuality.
751 * khw, at the time of this commit, looked at the source for both gcc and clang
752 * to verify this. (gcc used a method inferior to deBruijn.) */
754 /* Below are functions to find the first, last, or only set bit in a word. On
755 * platforms with 64-bit capability, there is a pair for each operation; the
756 * first taking a 64 bit operand, and the second a 32 bit one. The logic is
757 * the same in each pair, so the second is stripped of most comments. */
759 #ifdef U64TYPE /* HAS_QUAD not usable outside the core */
761 PERL_STATIC_INLINE unsigned
762 Perl_lsbit_pos64(U64 word)
764 /* Find the position (0..63) of the least significant set bit in the input
769 /* If we can determine that the platform has a usable fast method to get
770 * this info, use that */
772 # if defined(PERL_CTZ_64)
773 # define PERL_HAS_FAST_GET_LSB_POS64
775 return (unsigned) PERL_CTZ_64(word);
777 # elif U64SIZE == 8 && defined(_WIN64) && defined(_MSC_VER)
778 # define PERL_HAS_FAST_GET_LSB_POS64
782 _BitScanForward64(&index, word);
783 return (unsigned)index;
788 /* Here, we didn't find a fast method for finding the lsb. Fall back to
789 * making the lsb the only set bit in the word, and use our function that
790 * works on words with a single bit set.
793 * https://stackoverflow.com/questions/757059/position-of-least-significant-bit-that-is-set
795 * The word will look like this, with a rightmost set bit in position 's':
796 * ('x's are don't cares, and 'y's are their complements)
799 * y..y011..11 Complement
801 * 0..0100..00 And with the original
803 * (Yes, complementing and adding 1 is just taking the negative on 2's
804 * complement machines, but not on 1's complement ones, and some compilers
805 * complain about negating an unsigned.)
807 return single_1bit_pos64(word & (~word + 1));
813 # define lsbit_pos_uintmax_(word) lsbit_pos64(word)
815 # define lsbit_pos_uintmax_(word) lsbit_pos32(word)
818 PERL_STATIC_INLINE unsigned /* Like above for 32 bit word */
819 Perl_lsbit_pos32(U32 word)
821 /* Find the position (0..31) of the least significant set bit in the input
826 #if defined(PERL_CTZ_32)
827 # define PERL_HAS_FAST_GET_LSB_POS32
829 return (unsigned) PERL_CTZ_32(word);
831 #elif U32SIZE == 4 && defined(_MSC_VER)
832 # define PERL_HAS_FAST_GET_LSB_POS32
836 _BitScanForward(&index, word);
837 return (unsigned)index;
842 return single_1bit_pos32(word & (~word + 1));
849 /* Convert the leading zeros count to the bit position of the first set bit.
850 * This just subtracts from the highest position, 31 or 63. But some compilers
851 * don't optimize this optimally, and so a bit of bit twiddling encourages them
852 * to do the right thing. It turns out that subtracting a smaller non-negative
853 * number 'x' from 2**n-1 for any n is the same as taking the exclusive-or of
854 * the two numbers. To see why, first note that the sum of any number, x, and
855 * its complement, x', is all ones. So all ones minus x is x'. Then note that
856 * the xor of x and all ones is x'. */
857 #define LZC_TO_MSBIT_POS_(size, lzc) ((size##SIZE * CHARBITS - 1) ^ (lzc))
859 #ifdef U64TYPE /* HAS_QUAD not usable outside the core */
861 PERL_STATIC_INLINE unsigned
862 Perl_msbit_pos64(U64 word)
864 /* Find the position (0..63) of the most significant set bit in the input
869 /* If we can determine that the platform has a usable fast method to get
872 # if defined(PERL_CLZ_64)
873 # define PERL_HAS_FAST_GET_MSB_POS64
875 return (unsigned) LZC_TO_MSBIT_POS_(U64, PERL_CLZ_64(word));
877 # elif U64SIZE == 8 && defined(_WIN64) && defined(_MSC_VER)
878 # define PERL_HAS_FAST_GET_MSB_POS64
882 _BitScanReverse64(&index, word);
883 return (unsigned)index;
888 /* Here, we didn't find a fast method for finding the msb. Fall back to
889 * making the msb the only set bit in the word, and use our function that
890 * works on words with a single bit set.
892 * Isolate the msb; http://codeforces.com/blog/entry/10330
894 * Only the most significant set bit matters. Or'ing word with its right
895 * shift of 1 makes that bit and the next one to its right both 1.
896 * Repeating that with the right shift of 2 makes for 4 1-bits in a row.
897 * ... We end with the msb and all to the right being 1. */
902 word |= (word >> 16);
903 word |= (word >> 32);
905 /* Then subtracting the right shift by 1 clears all but the left-most of
906 * the 1 bits, which is our desired result */
909 /* Now we have a single bit set */
910 return single_1bit_pos64(word);
916 # define msbit_pos_uintmax_(word) msbit_pos64(word)
918 # define msbit_pos_uintmax_(word) msbit_pos32(word)
921 PERL_STATIC_INLINE unsigned
922 Perl_msbit_pos32(U32 word)
924 /* Find the position (0..31) of the most significant set bit in the input
929 #if defined(PERL_CLZ_32)
930 # define PERL_HAS_FAST_GET_MSB_POS32
932 return (unsigned) LZC_TO_MSBIT_POS_(U32, PERL_CLZ_32(word));
934 #elif U32SIZE == 4 && defined(_MSC_VER)
935 # define PERL_HAS_FAST_GET_MSB_POS32
939 _BitScanReverse(&index, word);
940 return (unsigned)index;
949 word |= (word >> 16);
951 return single_1bit_pos32(word);
957 #if UVSIZE == U64SIZE
958 # define msbit_pos(word) msbit_pos64(word)
959 # define lsbit_pos(word) lsbit_pos64(word)
960 #elif UVSIZE == U32SIZE
961 # define msbit_pos(word) msbit_pos32(word)
962 # define lsbit_pos(word) lsbit_pos32(word)
965 #ifdef U64TYPE /* HAS_QUAD not usable outside the core */
967 PERL_STATIC_INLINE unsigned
968 Perl_single_1bit_pos64(U64 word)
970 /* Given a 64-bit word known to contain all zero bits except one 1 bit,
971 * find and return the 1's position: 0..63 */
973 # ifdef PERL_CORE /* macro not exported */
974 ASSUME(isPOWER_OF_2(word));
976 ASSUME(word && (word & (word-1)) == 0);
979 /* The only set bit is both the most and least significant bit. If we have
980 * a fast way of finding either one, use that.
982 * It may appear at first glance that those functions call this one, but
983 * they don't if the corresponding #define is set */
985 # ifdef PERL_HAS_FAST_GET_MSB_POS64
987 return msbit_pos64(word);
989 # elif defined(PERL_HAS_FAST_GET_LSB_POS64)
991 return lsbit_pos64(word);
995 /* The position of the only set bit in a word can be quickly calculated
996 * using deBruijn sequences. See for example
997 * https://en.wikipedia.org/wiki/De_Bruijn_sequence */
998 return PL_deBruijn_bitpos_tab64[(word * PERL_deBruijnMagic64_)
999 >> PERL_deBruijnShift64_];
1006 PERL_STATIC_INLINE unsigned
1007 Perl_single_1bit_pos32(U32 word)
1009 /* Given a 32-bit word known to contain all zero bits except one 1 bit,
1010 * find and return the 1's position: 0..31 */
1012 #ifdef PERL_CORE /* macro not exported */
1013 ASSUME(isPOWER_OF_2(word));
1015 ASSUME(word && (word & (word-1)) == 0);
1017 #ifdef PERL_HAS_FAST_GET_MSB_POS32
1019 return msbit_pos32(word);
1021 #elif defined(PERL_HAS_FAST_GET_LSB_POS32)
1023 return lsbit_pos32(word);
1025 /* Unlikely, but possible for the platform to have a wider fast operation but
1026 * not a narrower one. But easy enough to handle the case by widening the
1027 * parameter size. (Going the other way, emulating 64 bit by two 32 bit ops
1028 * would be slower than the deBruijn method.) */
1029 #elif defined(PERL_HAS_FAST_GET_MSB_POS64)
1031 return msbit_pos64(word);
1033 #elif defined(PERL_HAS_FAST_GET_LSB_POS64)
1035 return lsbit_pos64(word);
1039 return PL_deBruijn_bitpos_tab32[(word * PERL_deBruijnMagic32_)
1040 >> PERL_deBruijnShift32_];
1047 PERL_STATIC_INLINE unsigned int
1048 Perl_variant_byte_number(PERL_UINTMAX_T word)
1050 /* This returns the position in a word (0..7) of the first variant byte in
1051 * it. This is a helper function. Note that there are no branches */
1053 /* Get just the msb bits of each byte */
1054 word &= PERL_VARIANTS_WORD_MASK;
1056 /* This should only be called if we know there is a variant byte in the
1060 # if BYTEORDER == 0x1234 || BYTEORDER == 0x12345678
1062 /* Bytes are stored like
1063 * Byte8 ... Byte2 Byte1
1064 * 63..56...15...8 7...0
1065 * so getting the lsb of the whole modified word is getting the msb of the
1066 * first byte that has its msb set */
1067 word = lsbit_pos_uintmax_(word);
1069 /* Here, word contains the position 7,15,23,...55,63 of that bit. Convert
1071 return (unsigned int) ((word + 1) >> 3) - 1;
1073 # elif BYTEORDER == 0x4321 || BYTEORDER == 0x87654321
1075 /* Bytes are stored like
1076 * Byte1 Byte2 ... Byte8
1077 * 63..56 55..47 ... 7...0
1078 * so getting the msb of the whole modified word is getting the msb of the
1079 * first byte that has its msb set */
1080 word = msbit_pos_uintmax_(word);
1082 /* Here, word contains the position 63,55,...,23,15,7 of that bit. Convert
1084 word = ((word + 1) >> 3) - 1;
1086 /* And invert the result because of the reversed byte order on this
1088 word = CHARBITS - word - 1;
1090 return (unsigned int) word;
1093 # error Unexpected byte order
1099 #if defined(PERL_CORE) || defined(PERL_EXT)
1102 =for apidoc variant_under_utf8_count
1104 This function looks at the sequence of bytes between C<s> and C<e>, which are
1105 assumed to be encoded in ASCII/Latin1, and returns how many of them would
1106 change should the string be translated into UTF-8. Due to the nature of UTF-8,
1107 each of these would occupy two bytes instead of the single one in the input
1108 string. Thus, this function returns the precise number of bytes the string
1109 would expand by when translated to UTF-8.
1111 Unlike most of the other functions that have C<utf8> in their name, the input
1112 to this function is NOT a UTF-8-encoded string. The function name is slightly
1113 I<odd> to emphasize this.
1115 This function is internal to Perl because khw thinks that any XS code that
1116 would want this is probably operating too close to the internals. Presenting a
1117 valid use case could change that.
1120 C<L<perlapi/is_utf8_invariant_string>>
1122 C<L<perlapi/is_utf8_invariant_string_loc>>,
1128 PERL_STATIC_INLINE Size_t
1129 S_variant_under_utf8_count(const U8* const s, const U8* const e)
1134 PERL_ARGS_ASSERT_VARIANT_UNDER_UTF8_COUNT;
1138 /* Test if the string is long enough to use word-at-a-time. (Logic is the
1139 * same as for is_utf8_invariant_string()) */
1140 if ((STRLEN) (e - x) >= PERL_WORDSIZE
1141 + PERL_WORDSIZE * PERL_IS_SUBWORD_ADDR(x)
1142 - (PTR2nat(x) & PERL_WORD_BOUNDARY_MASK))
1145 /* Process per-byte until reach word boundary. XXX This loop could be
1146 * eliminated if we knew that this platform had fast unaligned reads */
1147 while (PTR2nat(x) & PERL_WORD_BOUNDARY_MASK) {
1148 count += ! UTF8_IS_INVARIANT(*x++);
1151 /* Process per-word as long as we have at least a full word left */
1152 do { /* Commit 03c1e4ab1d6ee9062fb3f94b0ba31db6698724b1 contains an
1153 explanation of how this works */
1154 PERL_UINTMAX_T increment
1155 = ((((* (PERL_UINTMAX_T *) x) & PERL_VARIANTS_WORD_MASK) >> 7)
1156 * PERL_COUNT_MULTIPLIER)
1157 >> ((PERL_WORDSIZE - 1) * CHARBITS);
1158 count += (Size_t) increment;
1160 } while (x + PERL_WORDSIZE <= e);
1165 /* Process per-byte */
1167 if (! UTF8_IS_INVARIANT(*x)) {
1179 #ifndef PERL_IN_REGEXEC_C /* Keep these around for that file */
1180 # undef PERL_WORDSIZE
1181 # undef PERL_COUNT_MULTIPLIER
1182 # undef PERL_WORD_BOUNDARY_MASK
1183 # undef PERL_VARIANTS_WORD_MASK
1187 =for apidoc is_utf8_string
1189 Returns TRUE if the first C<len> bytes of string C<s> form a valid
1190 Perl-extended-UTF-8 string; returns FALSE otherwise. If C<len> is 0, it will
1191 be calculated using C<strlen(s)> (which means if you use this option, that C<s>
1192 can't have embedded C<NUL> characters and has to have a terminating C<NUL>
1193 byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
1195 This function considers Perl's extended UTF-8 to be valid. That means that
1196 code points above Unicode, surrogates, and non-character code points are
1197 considered valid by this function. Use C<L</is_strict_utf8_string>>,
1198 C<L</is_c9strict_utf8_string>>, or C<L</is_utf8_string_flags>> to restrict what
1199 code points are considered valid.
1202 C<L</is_utf8_invariant_string>>,
1203 C<L</is_utf8_invariant_string_loc>>,
1204 C<L</is_utf8_string_loc>>,
1205 C<L</is_utf8_string_loclen>>,
1206 C<L</is_utf8_fixed_width_buf_flags>>,
1207 C<L</is_utf8_fixed_width_buf_loc_flags>>,
1208 C<L</is_utf8_fixed_width_buf_loclen_flags>>,
1213 #define is_utf8_string(s, len) is_utf8_string_loclen(s, len, NULL, NULL)
1215 #if defined(PERL_CORE) || defined (PERL_EXT)
1218 =for apidoc is_utf8_non_invariant_string
1220 Returns TRUE if L<perlapi/is_utf8_invariant_string> returns FALSE for the first
1221 C<len> bytes of the string C<s>, but they are, nonetheless, legal Perl-extended
1222 UTF-8; otherwise returns FALSE.
1224 A TRUE return means that at least one code point represented by the sequence
1225 either is a wide character not representable as a single byte, or the
1226 representation differs depending on whether the sequence is encoded in UTF-8 or
1230 C<L<perlapi/is_utf8_invariant_string>>,
1231 C<L<perlapi/is_utf8_string>>
1235 This is commonly used to determine if a SV's UTF-8 flag should be turned on.
1236 It generally needn't be if its string is entirely UTF-8 invariant, and it
1237 shouldn't be if it otherwise contains invalid UTF-8.
1239 It is an internal function because khw thinks that XS code shouldn't be working
1240 at this low a level. A valid use case could change that.
1244 PERL_STATIC_INLINE bool
1245 Perl_is_utf8_non_invariant_string(const U8* const s, STRLEN len)
1247 const U8 * first_variant;
1249 PERL_ARGS_ASSERT_IS_UTF8_NON_INVARIANT_STRING;
1251 if (is_utf8_invariant_string_loc(s, len, &first_variant)) {
1255 return is_utf8_string(first_variant, len - (first_variant - s));
1261 =for apidoc is_strict_utf8_string
1263 Returns TRUE if the first C<len> bytes of string C<s> form a valid
1264 UTF-8-encoded string that is fully interchangeable by any application using
1265 Unicode rules; otherwise it returns FALSE. If C<len> is 0, it will be
1266 calculated using C<strlen(s)> (which means if you use this option, that C<s>
1267 can't have embedded C<NUL> characters and has to have a terminating C<NUL>
1268 byte). Note that all characters being ASCII constitute 'a valid UTF-8 string'.
1270 This function returns FALSE for strings containing any
1271 code points above the Unicode max of 0x10FFFF, surrogate code points, or
1272 non-character code points.
1275 C<L</is_utf8_invariant_string>>,
1276 C<L</is_utf8_invariant_string_loc>>,
1277 C<L</is_utf8_string>>,
1278 C<L</is_utf8_string_flags>>,
1279 C<L</is_utf8_string_loc>>,
1280 C<L</is_utf8_string_loc_flags>>,
1281 C<L</is_utf8_string_loclen>>,
1282 C<L</is_utf8_string_loclen_flags>>,
1283 C<L</is_utf8_fixed_width_buf_flags>>,
1284 C<L</is_utf8_fixed_width_buf_loc_flags>>,
1285 C<L</is_utf8_fixed_width_buf_loclen_flags>>,
1286 C<L</is_strict_utf8_string_loc>>,
1287 C<L</is_strict_utf8_string_loclen>>,
1288 C<L</is_c9strict_utf8_string>>,
1289 C<L</is_c9strict_utf8_string_loc>>,
1291 C<L</is_c9strict_utf8_string_loclen>>.
1296 #define is_strict_utf8_string(s, len) is_strict_utf8_string_loclen(s, len, NULL, NULL)
1299 =for apidoc is_c9strict_utf8_string
1301 Returns TRUE if the first C<len> bytes of string C<s> form a valid
1302 UTF-8-encoded string that conforms to
1303 L<Unicode Corrigendum #9|http://www.unicode.org/versions/corrigendum9.html>;
1304 otherwise it returns FALSE. If C<len> is 0, it will be calculated using
1305 C<strlen(s)> (which means if you use this option, that C<s> can't have embedded
1306 C<NUL> characters and has to have a terminating C<NUL> byte). Note that all
1307 characters being ASCII constitute 'a valid UTF-8 string'.
1309 This function returns FALSE for strings containing any code points above the
1310 Unicode max of 0x10FFFF or surrogate code points, but accepts non-character
1312 L<Corrigendum #9|http://www.unicode.org/versions/corrigendum9.html>.
1315 C<L</is_utf8_invariant_string>>,
1316 C<L</is_utf8_invariant_string_loc>>,
1317 C<L</is_utf8_string>>,
1318 C<L</is_utf8_string_flags>>,
1319 C<L</is_utf8_string_loc>>,
1320 C<L</is_utf8_string_loc_flags>>,
1321 C<L</is_utf8_string_loclen>>,
1322 C<L</is_utf8_string_loclen_flags>>,
1323 C<L</is_utf8_fixed_width_buf_flags>>,
1324 C<L</is_utf8_fixed_width_buf_loc_flags>>,
1325 C<L</is_utf8_fixed_width_buf_loclen_flags>>,
1326 C<L</is_strict_utf8_string>>,
1327 C<L</is_strict_utf8_string_loc>>,
1328 C<L</is_strict_utf8_string_loclen>>,
1329 C<L</is_c9strict_utf8_string_loc>>,
1331 C<L</is_c9strict_utf8_string_loclen>>.
1336 #define is_c9strict_utf8_string(s, len) is_c9strict_utf8_string_loclen(s, len, NULL, 0)
1339 =for apidoc is_utf8_string_flags
1341 Returns TRUE if the first C<len> bytes of string C<s> form a valid
1342 UTF-8 string, subject to the restrictions imposed by C<flags>;
1343 returns FALSE otherwise. If C<len> is 0, it will be calculated
1344 using C<strlen(s)> (which means if you use this option, that C<s> can't have
1345 embedded C<NUL> characters and has to have a terminating C<NUL> byte). Note
1346 that all characters being ASCII constitute 'a valid UTF-8 string'.
1348 If C<flags> is 0, this gives the same results as C<L</is_utf8_string>>; if
1349 C<flags> is C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>, this gives the same results
1350 as C<L</is_strict_utf8_string>>; and if C<flags> is
1351 C<UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE>, this gives the same results as
1352 C<L</is_c9strict_utf8_string>>. Otherwise C<flags> may be any
1353 combination of the C<UTF8_DISALLOW_I<foo>> flags understood by
1354 C<L</utf8n_to_uvchr>>, with the same meanings.
1357 C<L</is_utf8_invariant_string>>,
1358 C<L</is_utf8_invariant_string_loc>>,
1359 C<L</is_utf8_string>>,
1360 C<L</is_utf8_string_loc>>,
1361 C<L</is_utf8_string_loc_flags>>,
1362 C<L</is_utf8_string_loclen>>,
1363 C<L</is_utf8_string_loclen_flags>>,
1364 C<L</is_utf8_fixed_width_buf_flags>>,
1365 C<L</is_utf8_fixed_width_buf_loc_flags>>,
1366 C<L</is_utf8_fixed_width_buf_loclen_flags>>,
1367 C<L</is_strict_utf8_string>>,
1368 C<L</is_strict_utf8_string_loc>>,
1369 C<L</is_strict_utf8_string_loclen>>,
1370 C<L</is_c9strict_utf8_string>>,
1371 C<L</is_c9strict_utf8_string_loc>>,
1373 C<L</is_c9strict_utf8_string_loclen>>.
1378 PERL_STATIC_INLINE bool
1379 Perl_is_utf8_string_flags(const U8 *s, STRLEN len, const U32 flags)
1381 const U8 * first_variant;
1383 PERL_ARGS_ASSERT_IS_UTF8_STRING_FLAGS;
1384 assert(0 == (flags & ~(UTF8_DISALLOW_ILLEGAL_INTERCHANGE
1385 |UTF8_DISALLOW_PERL_EXTENDED)));
1388 len = strlen((const char *)s);
1392 return is_utf8_string(s, len);
1395 if ((flags & ~UTF8_DISALLOW_PERL_EXTENDED)
1396 == UTF8_DISALLOW_ILLEGAL_INTERCHANGE)
1398 return is_strict_utf8_string(s, len);
1401 if ((flags & ~UTF8_DISALLOW_PERL_EXTENDED)
1402 == UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE)
1404 return is_c9strict_utf8_string(s, len);
1407 if (! is_utf8_invariant_string_loc(s, len, &first_variant)) {
1408 const U8* const send = s + len;
1409 const U8* x = first_variant;
1412 STRLEN cur_len = isUTF8_CHAR_flags(x, send, flags);
1413 if (UNLIKELY(! cur_len)) {
1425 =for apidoc is_utf8_string_loc
1427 Like C<L</is_utf8_string>> but stores the location of the failure (in the
1428 case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1429 "utf8ness success") in the C<ep> pointer.
1431 See also C<L</is_utf8_string_loclen>>.
1436 #define is_utf8_string_loc(s, len, ep) is_utf8_string_loclen(s, len, ep, 0)
1440 =for apidoc is_utf8_string_loclen
1442 Like C<L</is_utf8_string>> but stores the location of the failure (in the
1443 case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1444 "utf8ness success") in the C<ep> pointer, and the number of UTF-8
1445 encoded characters in the C<el> pointer.
1447 See also C<L</is_utf8_string_loc>>.
1452 PERL_STATIC_INLINE bool
1453 Perl_is_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)
1455 const U8 * first_variant;
1457 PERL_ARGS_ASSERT_IS_UTF8_STRING_LOCLEN;
1460 len = strlen((const char *) s);
1463 if (is_utf8_invariant_string_loc(s, len, &first_variant)) {
1475 const U8* const send = s + len;
1476 const U8* x = first_variant;
1477 STRLEN outlen = first_variant - s;
1480 const STRLEN cur_len = isUTF8_CHAR(x, send);
1481 if (UNLIKELY(! cur_len)) {
1499 /* The perl core arranges to never call the DFA below without there being at
1500 * least one byte available to look at. This allows the DFA to use a do {}
1501 * while loop which means that calling it with a UTF-8 invariant has a single
1502 * conditional, same as the calling code checking for invariance ahead of time.
1503 * And having the calling code remove that conditional speeds up by that
1504 * conditional, the case where it wasn't invariant. So there's no reason to
1505 * check before caling this.
1507 * But we don't know this for non-core calls, so have to retain the check for
1510 # define PERL_NON_CORE_CHECK_EMPTY(s,e) assert((e) > (s))
1512 # define PERL_NON_CORE_CHECK_EMPTY(s,e) if ((e) <= (s)) return FALSE
1516 * DFA for checking input is valid UTF-8 syntax.
1518 * This uses adaptations of the table and algorithm given in
1519 * https://bjoern.hoehrmann.de/utf-8/decoder/dfa/, which provides comprehensive
1520 * documentation of the original version. A copyright notice for the original
1521 * version is given at the beginning of this file. The Perl adapations are
1522 * documented at the definition of PL_extended_utf8_dfa_tab[].
1524 * This dfa is fast. There are three exit conditions:
1525 * 1) a well-formed code point, acceptable to the table
1526 * 2) the beginning bytes of an incomplete character, whose completion might
1527 * or might not be acceptable
1528 * 3) unacceptable to the table. Some of the adaptations have certain,
1529 * hopefully less likely to occur, legal inputs be unacceptable to the
1530 * table, so these must be sorted out afterwards.
1532 * This macro is a complete implementation of the code executing the DFA. It
1533 * is passed the input sequence bounds and the table to use, and what to do
1534 * for each of the exit conditions. There are three canned actions, likely to
1535 * be the ones you want:
1536 * DFA_RETURN_SUCCESS_
1537 * DFA_RETURN_FAILURE_
1538 * DFA_GOTO_TEASE_APART_FF_
1540 * You pass a parameter giving the action to take for each of the three
1541 * possible exit conditions:
1543 * 'accept_action' This is executed when the DFA accepts the input.
1544 * DFA_RETURN_SUCCESS_ is the most likely candidate.
1545 * 'reject_action' This is executed when the DFA rejects the input.
1546 * DFA_RETURN_FAILURE_ is a candidate, or 'goto label' where
1547 * you have written code to distinguish the rejecting state
1548 * results. Because it happens in several places, and
1549 * involves #ifdefs, the special action
1550 * DFA_GOTO_TEASE_APART_FF_ is what you want with
1551 * PL_extended_utf8_dfa_tab. On platforms without
1552 * EXTRA_LONG_UTF8, there is no need to tease anything apart,
1553 * so this evaluates to DFA_RETURN_FAILURE_; otherwise you
1554 * need to have a label 'tease_apart_FF' that it will transfer
1556 * 'incomplete_char_action' This is executed when the DFA ran off the end
1557 * before accepting or rejecting the input.
1558 * DFA_RETURN_FAILURE_ is the likely action, but you could
1559 * have a 'goto', or NOOP. In the latter case the DFA drops
1560 * off the end, and you place your code to handle this case
1561 * immediately after it.
1564 #define DFA_RETURN_SUCCESS_ return s - s0
1565 #define DFA_RETURN_FAILURE_ return 0
1566 #ifdef HAS_EXTRA_LONG_UTF8
1567 # define DFA_TEASE_APART_FF_ goto tease_apart_FF
1569 # define DFA_TEASE_APART_FF_ DFA_RETURN_FAILURE_
1572 #define PERL_IS_UTF8_CHAR_DFA(s0, e, dfa_tab, \
1575 incomplete_char_action) \
1577 const U8 * s = s0; \
1580 PERL_NON_CORE_CHECK_EMPTY(s,e); \
1583 state = dfa_tab[256 + state + dfa_tab[*s]]; \
1586 if (state == 0) { /* Accepting state */ \
1590 if (UNLIKELY(state == 1)) { /* Rejecting state */ \
1595 /* Here, dropped out of loop before end-of-char */ \
1596 incomplete_char_action; \
1602 =for apidoc isUTF8_CHAR
1604 Evaluates to non-zero if the first few bytes of the string starting at C<s> and
1605 looking no further than S<C<e - 1>> are well-formed UTF-8, as extended by Perl,
1606 that represents some code point; otherwise it evaluates to 0. If non-zero, the
1607 value gives how many bytes starting at C<s> comprise the code point's
1608 representation. Any bytes remaining before C<e>, but beyond the ones needed to
1609 form the first code point in C<s>, are not examined.
1611 The code point can be any that will fit in an IV on this machine, using Perl's
1612 extension to official UTF-8 to represent those higher than the Unicode maximum
1613 of 0x10FFFF. That means that this macro is used to efficiently decide if the
1614 next few bytes in C<s> is legal UTF-8 for a single character.
1616 Use C<L</isSTRICT_UTF8_CHAR>> to restrict the acceptable code points to those
1617 defined by Unicode to be fully interchangeable across applications;
1618 C<L</isC9_STRICT_UTF8_CHAR>> to use the L<Unicode Corrigendum
1619 #9|http://www.unicode.org/versions/corrigendum9.html> definition of allowable
1620 code points; and C<L</isUTF8_CHAR_flags>> for a more customized definition.
1622 Use C<L</is_utf8_string>>, C<L</is_utf8_string_loc>>, and
1623 C<L</is_utf8_string_loclen>> to check entire strings.
1625 Note also that a UTF-8 "invariant" character (i.e. ASCII on non-EBCDIC
1626 machines) is a valid UTF-8 character.
1630 This uses an adaptation of the table and algorithm given in
1631 https://bjoern.hoehrmann.de/utf-8/decoder/dfa/, which provides comprehensive
1632 documentation of the original version. A copyright notice for the original
1633 version is given at the beginning of this file. The Perl adapation is
1634 documented at the definition of PL_extended_utf8_dfa_tab[].
1637 PERL_STATIC_INLINE Size_t
1638 Perl_isUTF8_CHAR(const U8 * const s0, const U8 * const e)
1640 PERL_ARGS_ASSERT_ISUTF8_CHAR;
1642 PERL_IS_UTF8_CHAR_DFA(s0, e, PL_extended_utf8_dfa_tab,
1643 DFA_RETURN_SUCCESS_,
1644 DFA_TEASE_APART_FF_,
1645 DFA_RETURN_FAILURE_);
1647 /* Here, we didn't return success, but dropped out of the loop. In the
1648 * case of PL_extended_utf8_dfa_tab, this means the input is either
1649 * malformed, or the start byte was FF on a platform that the dfa doesn't
1650 * handle FF's. Call a helper function. */
1652 #ifdef HAS_EXTRA_LONG_UTF8
1656 /* In the case of PL_extended_utf8_dfa_tab, getting here means the input is
1657 * either malformed, or was for the largest possible start byte, which we
1658 * now check, not inline */
1659 if (*s0 != I8_TO_NATIVE_UTF8(0xFF)) {
1663 return is_utf8_FF_helper_(s0, e,
1664 FALSE /* require full, not partial char */
1672 =for apidoc isSTRICT_UTF8_CHAR
1674 Evaluates to non-zero if the first few bytes of the string starting at C<s> and
1675 looking no further than S<C<e - 1>> are well-formed UTF-8 that represents some
1676 Unicode code point completely acceptable for open interchange between all
1677 applications; otherwise it evaluates to 0. If non-zero, the value gives how
1678 many bytes starting at C<s> comprise the code point's representation. Any
1679 bytes remaining before C<e>, but beyond the ones needed to form the first code
1680 point in C<s>, are not examined.
1682 The largest acceptable code point is the Unicode maximum 0x10FFFF, and must not
1683 be a surrogate nor a non-character code point. Thus this excludes any code
1684 point from Perl's extended UTF-8.
1686 This is used to efficiently decide if the next few bytes in C<s> is
1687 legal Unicode-acceptable UTF-8 for a single character.
1689 Use C<L</isC9_STRICT_UTF8_CHAR>> to use the L<Unicode Corrigendum
1690 #9|http://www.unicode.org/versions/corrigendum9.html> definition of allowable
1691 code points; C<L</isUTF8_CHAR>> to check for Perl's extended UTF-8;
1692 and C<L</isUTF8_CHAR_flags>> for a more customized definition.
1694 Use C<L</is_strict_utf8_string>>, C<L</is_strict_utf8_string_loc>>, and
1695 C<L</is_strict_utf8_string_loclen>> to check entire strings.
1699 This uses an adaptation of the tables and algorithm given in
1700 https://bjoern.hoehrmann.de/utf-8/decoder/dfa/, which provides comprehensive
1701 documentation of the original version. A copyright notice for the original
1702 version is given at the beginning of this file. The Perl adapation is
1703 documented at the definition of strict_extended_utf8_dfa_tab[].
1707 PERL_STATIC_INLINE Size_t
1708 Perl_isSTRICT_UTF8_CHAR(const U8 * const s0, const U8 * const e)
1710 PERL_ARGS_ASSERT_ISSTRICT_UTF8_CHAR;
1712 PERL_IS_UTF8_CHAR_DFA(s0, e, PL_strict_utf8_dfa_tab,
1713 DFA_RETURN_SUCCESS_,
1715 DFA_RETURN_FAILURE_);
1718 /* Here, we didn't return success, but dropped out of the loop. In the
1719 * case of PL_strict_utf8_dfa_tab, this means the input is either
1720 * malformed, or was for certain Hanguls; handle them specially */
1722 /* The dfa above drops out for incomplete or illegal inputs, and certain
1723 * legal Hanguls; check and return accordingly */
1724 return is_HANGUL_ED_utf8_safe(s0, e);
1729 =for apidoc isC9_STRICT_UTF8_CHAR
1731 Evaluates to non-zero if the first few bytes of the string starting at C<s> and
1732 looking no further than S<C<e - 1>> are well-formed UTF-8 that represents some
1733 Unicode non-surrogate code point; otherwise it evaluates to 0. If non-zero,
1734 the value gives how many bytes starting at C<s> comprise the code point's
1735 representation. Any bytes remaining before C<e>, but beyond the ones needed to
1736 form the first code point in C<s>, are not examined.
1738 The largest acceptable code point is the Unicode maximum 0x10FFFF. This
1739 differs from C<L</isSTRICT_UTF8_CHAR>> only in that it accepts non-character
1740 code points. This corresponds to
1741 L<Unicode Corrigendum #9|http://www.unicode.org/versions/corrigendum9.html>.
1742 which said that non-character code points are merely discouraged rather than
1743 completely forbidden in open interchange. See
1744 L<perlunicode/Noncharacter code points>.
1746 Use C<L</isUTF8_CHAR>> to check for Perl's extended UTF-8; and
1747 C<L</isUTF8_CHAR_flags>> for a more customized definition.
1749 Use C<L</is_c9strict_utf8_string>>, C<L</is_c9strict_utf8_string_loc>>, and
1750 C<L</is_c9strict_utf8_string_loclen>> to check entire strings.
1754 This uses an adaptation of the tables and algorithm given in
1755 https://bjoern.hoehrmann.de/utf-8/decoder/dfa/, which provides comprehensive
1756 documentation of the original version. A copyright notice for the original
1757 version is given at the beginning of this file. The Perl adapation is
1758 documented at the definition of PL_c9_utf8_dfa_tab[].
1762 PERL_STATIC_INLINE Size_t
1763 Perl_isC9_STRICT_UTF8_CHAR(const U8 * const s0, const U8 * const e)
1765 PERL_ARGS_ASSERT_ISC9_STRICT_UTF8_CHAR;
1767 PERL_IS_UTF8_CHAR_DFA(s0, e, PL_c9_utf8_dfa_tab,
1768 DFA_RETURN_SUCCESS_,
1769 DFA_RETURN_FAILURE_,
1770 DFA_RETURN_FAILURE_);
1775 =for apidoc is_strict_utf8_string_loc
1777 Like C<L</is_strict_utf8_string>> but stores the location of the failure (in the
1778 case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1779 "utf8ness success") in the C<ep> pointer.
1781 See also C<L</is_strict_utf8_string_loclen>>.
1786 #define is_strict_utf8_string_loc(s, len, ep) \
1787 is_strict_utf8_string_loclen(s, len, ep, 0)
1791 =for apidoc is_strict_utf8_string_loclen
1793 Like C<L</is_strict_utf8_string>> but stores the location of the failure (in the
1794 case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1795 "utf8ness success") in the C<ep> pointer, and the number of UTF-8
1796 encoded characters in the C<el> pointer.
1798 See also C<L</is_strict_utf8_string_loc>>.
1803 PERL_STATIC_INLINE bool
1804 Perl_is_strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)
1806 const U8 * first_variant;
1808 PERL_ARGS_ASSERT_IS_STRICT_UTF8_STRING_LOCLEN;
1811 len = strlen((const char *) s);
1814 if (is_utf8_invariant_string_loc(s, len, &first_variant)) {
1826 const U8* const send = s + len;
1827 const U8* x = first_variant;
1828 STRLEN outlen = first_variant - s;
1831 const STRLEN cur_len = isSTRICT_UTF8_CHAR(x, send);
1832 if (UNLIKELY(! cur_len)) {
1852 =for apidoc is_c9strict_utf8_string_loc
1854 Like C<L</is_c9strict_utf8_string>> but stores the location of the failure (in
1855 the case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1856 "utf8ness success") in the C<ep> pointer.
1858 See also C<L</is_c9strict_utf8_string_loclen>>.
1863 #define is_c9strict_utf8_string_loc(s, len, ep) \
1864 is_c9strict_utf8_string_loclen(s, len, ep, 0)
1868 =for apidoc is_c9strict_utf8_string_loclen
1870 Like C<L</is_c9strict_utf8_string>> but stores the location of the failure (in
1871 the case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1872 "utf8ness success") in the C<ep> pointer, and the number of UTF-8 encoded
1873 characters in the C<el> pointer.
1875 See also C<L</is_c9strict_utf8_string_loc>>.
1880 PERL_STATIC_INLINE bool
1881 Perl_is_c9strict_utf8_string_loclen(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el)
1883 const U8 * first_variant;
1885 PERL_ARGS_ASSERT_IS_C9STRICT_UTF8_STRING_LOCLEN;
1888 len = strlen((const char *) s);
1891 if (is_utf8_invariant_string_loc(s, len, &first_variant)) {
1903 const U8* const send = s + len;
1904 const U8* x = first_variant;
1905 STRLEN outlen = first_variant - s;
1908 const STRLEN cur_len = isC9_STRICT_UTF8_CHAR(x, send);
1909 if (UNLIKELY(! cur_len)) {
1929 =for apidoc is_utf8_string_loc_flags
1931 Like C<L</is_utf8_string_flags>> but stores the location of the failure (in the
1932 case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1933 "utf8ness success") in the C<ep> pointer.
1935 See also C<L</is_utf8_string_loclen_flags>>.
1940 #define is_utf8_string_loc_flags(s, len, ep, flags) \
1941 is_utf8_string_loclen_flags(s, len, ep, 0, flags)
1944 /* The above 3 actual functions could have been moved into the more general one
1945 * just below, and made #defines that call it with the right 'flags'. They are
1946 * currently kept separate to increase their chances of getting inlined */
1950 =for apidoc is_utf8_string_loclen_flags
1952 Like C<L</is_utf8_string_flags>> but stores the location of the failure (in the
1953 case of "utf8ness failure") or the location C<s>+C<len> (in the case of
1954 "utf8ness success") in the C<ep> pointer, and the number of UTF-8
1955 encoded characters in the C<el> pointer.
1957 See also C<L</is_utf8_string_loc_flags>>.
1962 PERL_STATIC_INLINE bool
1963 Perl_is_utf8_string_loclen_flags(const U8 *s, STRLEN len, const U8 **ep, STRLEN *el, const U32 flags)
1965 const U8 * first_variant;
1967 PERL_ARGS_ASSERT_IS_UTF8_STRING_LOCLEN_FLAGS;
1968 assert(0 == (flags & ~(UTF8_DISALLOW_ILLEGAL_INTERCHANGE
1969 |UTF8_DISALLOW_PERL_EXTENDED)));
1972 len = strlen((const char *) s);
1976 return is_utf8_string_loclen(s, len, ep, el);
1979 if ((flags & ~UTF8_DISALLOW_PERL_EXTENDED)
1980 == UTF8_DISALLOW_ILLEGAL_INTERCHANGE)
1982 return is_strict_utf8_string_loclen(s, len, ep, el);
1985 if ((flags & ~UTF8_DISALLOW_PERL_EXTENDED)
1986 == UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE)
1988 return is_c9strict_utf8_string_loclen(s, len, ep, el);
1991 if (is_utf8_invariant_string_loc(s, len, &first_variant)) {
2003 const U8* send = s + len;
2004 const U8* x = first_variant;
2005 STRLEN outlen = first_variant - s;
2008 const STRLEN cur_len = isUTF8_CHAR_flags(x, send, flags);
2009 if (UNLIKELY(! cur_len)) {
2028 =for apidoc utf8_distance
2030 Returns the number of UTF-8 characters between the UTF-8 pointers C<a>
2033 WARNING: use only if you *know* that the pointers point inside the
2039 PERL_STATIC_INLINE IV
2040 Perl_utf8_distance(pTHX_ const U8 *a, const U8 *b)
2042 PERL_ARGS_ASSERT_UTF8_DISTANCE;
2044 return (a < b) ? -1 * (IV) utf8_length(a, b) : (IV) utf8_length(b, a);
2048 =for apidoc utf8_hop
2050 Return the UTF-8 pointer C<s> displaced by C<off> characters, either
2051 forward or backward.
2053 WARNING: do not use the following unless you *know* C<off> is within
2054 the UTF-8 data pointed to by C<s> *and* that on entry C<s> is aligned
2055 on the first byte of character or just after the last byte of a character.
2060 PERL_STATIC_INLINE U8 *
2061 Perl_utf8_hop(const U8 *s, SSize_t off)
2063 PERL_ARGS_ASSERT_UTF8_HOP;
2065 /* Note: cannot use UTF8_IS_...() too eagerly here since e.g
2066 * the bitops (especially ~) can create illegal UTF-8.
2067 * In other words: in Perl UTF-8 is not just for Unicode. */
2076 while (UTF8_IS_CONTINUATION(*s))
2080 GCC_DIAG_IGNORE(-Wcast-qual)
2086 =for apidoc utf8_hop_forward
2088 Return the UTF-8 pointer C<s> displaced by up to C<off> characters,
2091 C<off> must be non-negative.
2093 C<s> must be before or equal to C<end>.
2095 When moving forward it will not move beyond C<end>.
2097 Will not exceed this limit even if the string is not valid "UTF-8".
2102 PERL_STATIC_INLINE U8 *
2103 Perl_utf8_hop_forward(const U8 *s, SSize_t off, const U8 *end)
2105 PERL_ARGS_ASSERT_UTF8_HOP_FORWARD;
2107 /* Note: cannot use UTF8_IS_...() too eagerly here since e.g
2108 * the bitops (especially ~) can create illegal UTF-8.
2109 * In other words: in Perl UTF-8 is not just for Unicode. */
2115 STRLEN skip = UTF8SKIP(s);
2116 if ((STRLEN)(end - s) <= skip) {
2117 GCC_DIAG_IGNORE(-Wcast-qual)
2124 GCC_DIAG_IGNORE(-Wcast-qual)
2130 =for apidoc utf8_hop_back
2132 Return the UTF-8 pointer C<s> displaced by up to C<off> characters,
2135 C<off> must be non-positive.
2137 C<s> must be after or equal to C<start>.
2139 When moving backward it will not move before C<start>.
2141 Will not exceed this limit even if the string is not valid "UTF-8".
2146 PERL_STATIC_INLINE U8 *
2147 Perl_utf8_hop_back(const U8 *s, SSize_t off, const U8 *start)
2149 PERL_ARGS_ASSERT_UTF8_HOP_BACK;
2151 /* Note: cannot use UTF8_IS_...() too eagerly here since e.g
2152 * the bitops (especially ~) can create illegal UTF-8.
2153 * In other words: in Perl UTF-8 is not just for Unicode. */
2158 while (off++ && s > start) {
2161 } while (UTF8_IS_CONTINUATION(*s) && s > start);
2164 GCC_DIAG_IGNORE(-Wcast-qual)
2170 =for apidoc utf8_hop_safe
2172 Return the UTF-8 pointer C<s> displaced by up to C<off> characters,
2173 either forward or backward.
2175 When moving backward it will not move before C<start>.
2177 When moving forward it will not move beyond C<end>.
2179 Will not exceed those limits even if the string is not valid "UTF-8".
2184 PERL_STATIC_INLINE U8 *
2185 Perl_utf8_hop_safe(const U8 *s, SSize_t off, const U8 *start, const U8 *end)
2187 PERL_ARGS_ASSERT_UTF8_HOP_SAFE;
2189 /* Note: cannot use UTF8_IS_...() too eagerly here since e.g
2190 * the bitops (especially ~) can create illegal UTF-8.
2191 * In other words: in Perl UTF-8 is not just for Unicode. */
2193 assert(start <= s && s <= end);
2196 return utf8_hop_forward(s, off, end);
2199 return utf8_hop_back(s, off, start);
2205 =for apidoc isUTF8_CHAR_flags
2207 Evaluates to non-zero if the first few bytes of the string starting at C<s> and
2208 looking no further than S<C<e - 1>> are well-formed UTF-8, as extended by Perl,
2209 that represents some code point, subject to the restrictions given by C<flags>;
2210 otherwise it evaluates to 0. If non-zero, the value gives how many bytes
2211 starting at C<s> comprise the code point's representation. Any bytes remaining
2212 before C<e>, but beyond the ones needed to form the first code point in C<s>,
2215 If C<flags> is 0, this gives the same results as C<L</isUTF8_CHAR>>;
2216 if C<flags> is C<UTF8_DISALLOW_ILLEGAL_INTERCHANGE>, this gives the same results
2217 as C<L</isSTRICT_UTF8_CHAR>>;
2218 and if C<flags> is C<UTF8_DISALLOW_ILLEGAL_C9_INTERCHANGE>, this gives
2219 the same results as C<L</isC9_STRICT_UTF8_CHAR>>.
2220 Otherwise C<flags> may be any combination of the C<UTF8_DISALLOW_I<foo>> flags
2221 understood by C<L</utf8n_to_uvchr>>, with the same meanings.
2223 The three alternative macros are for the most commonly needed validations; they
2224 are likely to run somewhat faster than this more general one, as they can be
2225 inlined into your code.
2227 Use L</is_utf8_string_flags>, L</is_utf8_string_loc_flags>, and
2228 L</is_utf8_string_loclen_flags> to check entire strings.
2233 PERL_STATIC_INLINE STRLEN
2234 Perl_isUTF8_CHAR_flags(const U8 * const s0, const U8 * const e, const U32 flags)
2236 PERL_ARGS_ASSERT_ISUTF8_CHAR_FLAGS;
2237 assert(0 == (flags & ~(UTF8_DISALLOW_ILLEGAL_INTERCHANGE
2238 |UTF8_DISALLOW_PERL_EXTENDED)));
2240 PERL_IS_UTF8_CHAR_DFA(s0, e, PL_extended_utf8_dfa_tab,
2242 DFA_TEASE_APART_FF_,
2243 DFA_RETURN_FAILURE_);
2247 return is_utf8_char_helper_(s0, e, flags);
2249 #ifdef HAS_EXTRA_LONG_UTF8
2253 /* In the case of PL_extended_utf8_dfa_tab, getting here means the input is
2254 * either malformed, or was for the largest possible start byte, which
2255 * indicates perl extended UTF-8, well above the Unicode maximum */
2256 if ( *s0 != I8_TO_NATIVE_UTF8(0xFF)
2257 || (flags & (UTF8_DISALLOW_SUPER|UTF8_DISALLOW_PERL_EXTENDED)))
2262 /* Otherwise examine the sequence not inline */
2263 return is_utf8_FF_helper_(s0, e,
2264 FALSE /* require full, not partial char */
2272 =for apidoc is_utf8_valid_partial_char
2274 Returns 0 if the sequence of bytes starting at C<s> and looking no further than
2275 S<C<e - 1>> is the UTF-8 encoding, as extended by Perl, for one or more code
2276 points. Otherwise, it returns 1 if there exists at least one non-empty
2277 sequence of bytes that when appended to sequence C<s>, starting at position
2278 C<e> causes the entire sequence to be the well-formed UTF-8 of some code point;
2279 otherwise returns 0.
2281 In other words this returns TRUE if C<s> points to a partial UTF-8-encoded code
2284 This is useful when a fixed-length buffer is being tested for being well-formed
2285 UTF-8, but the final few bytes in it don't comprise a full character; that is,
2286 it is split somewhere in the middle of the final code point's UTF-8
2287 representation. (Presumably when the buffer is refreshed with the next chunk
2288 of data, the new first bytes will complete the partial code point.) This
2289 function is used to verify that the final bytes in the current buffer are in
2290 fact the legal beginning of some code point, so that if they aren't, the
2291 failure can be signalled without having to wait for the next read.
2295 #define is_utf8_valid_partial_char(s, e) \
2296 is_utf8_valid_partial_char_flags(s, e, 0)
2300 =for apidoc is_utf8_valid_partial_char_flags
2302 Like C<L</is_utf8_valid_partial_char>>, it returns a boolean giving whether
2303 or not the input is a valid UTF-8 encoded partial character, but it takes an
2304 extra parameter, C<flags>, which can further restrict which code points are
2307 If C<flags> is 0, this behaves identically to
2308 C<L</is_utf8_valid_partial_char>>. Otherwise C<flags> can be any combination
2309 of the C<UTF8_DISALLOW_I<foo>> flags accepted by C<L</utf8n_to_uvchr>>. If
2310 there is any sequence of bytes that can complete the input partial character in
2311 such a way that a non-prohibited character is formed, the function returns
2312 TRUE; otherwise FALSE. Non character code points cannot be determined based on
2313 partial character input. But many of the other possible excluded types can be
2314 determined from just the first one or two bytes.
2319 PERL_STATIC_INLINE bool
2320 Perl_is_utf8_valid_partial_char_flags(const U8 * const s0, const U8 * const e, const U32 flags)
2322 PERL_ARGS_ASSERT_IS_UTF8_VALID_PARTIAL_CHAR_FLAGS;
2323 assert(0 == (flags & ~(UTF8_DISALLOW_ILLEGAL_INTERCHANGE
2324 |UTF8_DISALLOW_PERL_EXTENDED)));
2326 PERL_IS_UTF8_CHAR_DFA(s0, e, PL_extended_utf8_dfa_tab,
2327 DFA_RETURN_FAILURE_,
2328 DFA_TEASE_APART_FF_,
2331 /* The NOOP above causes the DFA to drop down here iff the input was a
2332 * partial character. flags=0 => can return TRUE immediately; otherwise we
2333 * need to check (not inline) if the partial character is the beginning of
2334 * a disallowed one */
2339 return cBOOL(is_utf8_char_helper_(s0, e, flags));
2341 #ifdef HAS_EXTRA_LONG_UTF8
2345 /* Getting here means the input is either malformed, or, in the case of
2346 * PL_extended_utf8_dfa_tab, was for the largest possible start byte. The
2347 * latter case has to be extended UTF-8, so can fail immediately if that is
2350 if ( *s0 != I8_TO_NATIVE_UTF8(0xFF)
2351 || (flags & (UTF8_DISALLOW_SUPER|UTF8_DISALLOW_PERL_EXTENDED)))
2356 return is_utf8_FF_helper_(s0, e,
2357 TRUE /* Require to be a partial character */
2365 =for apidoc is_utf8_fixed_width_buf_flags
2367 Returns TRUE if the fixed-width buffer starting at C<s> with length C<len>
2368 is entirely valid UTF-8, subject to the restrictions given by C<flags>;
2369 otherwise it returns FALSE.
2371 If C<flags> is 0, any well-formed UTF-8, as extended by Perl, is accepted
2372 without restriction. If the final few bytes of the buffer do not form a
2373 complete code point, this will return TRUE anyway, provided that
2374 C<L</is_utf8_valid_partial_char_flags>> returns TRUE for them.
2376 If C<flags> in non-zero, it can be any combination of the
2377 C<UTF8_DISALLOW_I<foo>> flags accepted by C<L</utf8n_to_uvchr>>, and with the
2380 This function differs from C<L</is_utf8_string_flags>> only in that the latter
2381 returns FALSE if the final few bytes of the string don't form a complete code
2386 #define is_utf8_fixed_width_buf_flags(s, len, flags) \
2387 is_utf8_fixed_width_buf_loclen_flags(s, len, 0, 0, flags)
2391 =for apidoc is_utf8_fixed_width_buf_loc_flags
2393 Like C<L</is_utf8_fixed_width_buf_flags>> but stores the location of the
2394 failure in the C<ep> pointer. If the function returns TRUE, C<*ep> will point
2395 to the beginning of any partial character at the end of the buffer; if there is
2396 no partial character C<*ep> will contain C<s>+C<len>.
2398 See also C<L</is_utf8_fixed_width_buf_loclen_flags>>.
2403 #define is_utf8_fixed_width_buf_loc_flags(s, len, loc, flags) \
2404 is_utf8_fixed_width_buf_loclen_flags(s, len, loc, 0, flags)
2408 =for apidoc is_utf8_fixed_width_buf_loclen_flags
2410 Like C<L</is_utf8_fixed_width_buf_loc_flags>> but stores the number of
2411 complete, valid characters found in the C<el> pointer.
2416 PERL_STATIC_INLINE bool
2417 Perl_is_utf8_fixed_width_buf_loclen_flags(const U8 * const s,
2423 const U8 * maybe_partial;
2425 PERL_ARGS_ASSERT_IS_UTF8_FIXED_WIDTH_BUF_LOCLEN_FLAGS;
2428 ep = &maybe_partial;
2431 /* If it's entirely valid, return that; otherwise see if the only error is
2432 * that the final few bytes are for a partial character */
2433 return is_utf8_string_loclen_flags(s, len, ep, el, flags)
2434 || is_utf8_valid_partial_char_flags(*ep, s + len, flags);
2437 PERL_STATIC_INLINE UV
2438 Perl_utf8n_to_uvchr_msgs(const U8 *s,
2445 /* This is the inlined portion of utf8n_to_uvchr_msgs. It handles the
2446 * simple cases, and, if necessary calls a helper function to deal with the
2447 * more complex ones. Almost all well-formed non-problematic code points
2448 * are considered simple, so that it's unlikely that the helper function
2449 * will need to be called.
2451 * This is an adaptation of the tables and algorithm given in
2452 * https://bjoern.hoehrmann.de/utf-8/decoder/dfa/, which provides
2453 * comprehensive documentation of the original version. A copyright notice
2454 * for the original version is given at the beginning of this file. The
2455 * Perl adapation is documented at the definition of PL_strict_utf8_dfa_tab[].
2458 const U8 * const s0 = s;
2459 const U8 * send = s0 + curlen;
2460 UV uv = 0; /* The 0 silences some stupid compilers */
2463 PERL_ARGS_ASSERT_UTF8N_TO_UVCHR_MSGS;
2465 /* This dfa is fast. If it accepts the input, it was for a well-formed,
2466 * non-problematic code point, which can be returned immediately.
2467 * Otherwise we call a helper function to figure out the more complicated
2470 while (s < send && LIKELY(state != 1)) {
2471 UV type = PL_strict_utf8_dfa_tab[*s];
2474 ? ((0xff >> type) & NATIVE_UTF8_TO_I8(*s))
2475 : UTF8_ACCUMULATE(uv, *s);
2476 state = PL_strict_utf8_dfa_tab[256 + state + type];
2484 *retlen = s - s0 + 1;
2493 return UNI_TO_NATIVE(uv);
2496 /* Here is potentially problematic. Use the full mechanism */
2497 return _utf8n_to_uvchr_msgs_helper(s0, curlen, retlen, flags, errors, msgs);
2500 PERL_STATIC_INLINE UV
2501 Perl_utf8_to_uvchr_buf_helper(pTHX_ const U8 *s, const U8 *send, STRLEN *retlen)
2503 PERL_ARGS_ASSERT_UTF8_TO_UVCHR_BUF_HELPER;
2507 if (! ckWARN_d(WARN_UTF8)) {
2509 /* EMPTY is not really allowed, and asserts on debugging builds. But
2510 * on non-debugging we have to deal with it, and this causes it to
2511 * return the REPLACEMENT CHARACTER, as the documentation indicates */
2512 return utf8n_to_uvchr(s, send - s, retlen,
2513 (UTF8_ALLOW_ANY | UTF8_ALLOW_EMPTY));
2516 UV ret = utf8n_to_uvchr(s, send - s, retlen, 0);
2517 if (retlen && ret == 0 && *s != '\0') {
2518 *retlen = (STRLEN) -1;
2525 /* ------------------------------- perl.h ----------------------------- */
2528 =for apidoc_section $utility
2530 =for apidoc is_safe_syscall
2532 Test that the given C<pv> (with length C<len>) doesn't contain any internal
2534 If it does, set C<errno> to C<ENOENT>, optionally warn using the C<syscalls>
2535 category, and return FALSE.
2537 Return TRUE if the name is safe.
2539 C<what> and C<op_name> are used in any warning.
2541 Used by the C<IS_SAFE_SYSCALL()> macro.
2546 PERL_STATIC_INLINE bool
2547 Perl_is_safe_syscall(pTHX_ const char *pv, STRLEN len, const char *what, const char *op_name)
2549 /* While the Windows CE API provides only UCS-16 (or UTF-16) APIs
2550 * perl itself uses xce*() functions which accept 8-bit strings.
2553 PERL_ARGS_ASSERT_IS_SAFE_SYSCALL;
2557 if (UNLIKELY((null_at = (char *)memchr(pv, 0, len-1)) != NULL)) {
2558 SETERRNO(ENOENT, LIB_INVARG);
2559 Perl_ck_warner(aTHX_ packWARN(WARN_SYSCALLS),
2560 "Invalid \\0 character in %s for %s: %s\\0%s",
2561 what, op_name, pv, null_at+1);
2571 Return true if the supplied filename has a newline character
2572 immediately before the first (hopefully only) NUL.
2574 My original look at this incorrectly used the len from SvPV(), but
2575 that's incorrect, since we allow for a NUL in pv[len-1].
2577 So instead, strlen() and work from there.
2579 This allow for the user reading a filename, forgetting to chomp it,
2582 open my $foo, "$file\0";
2588 PERL_STATIC_INLINE bool
2589 S_should_warn_nl(const char *pv)
2593 PERL_ARGS_ASSERT_SHOULD_WARN_NL;
2597 return len > 0 && pv[len-1] == '\n';
2602 #if defined(PERL_IN_PP_C) || defined(PERL_IN_PP_HOT_C)
2604 PERL_STATIC_INLINE bool
2605 S_lossless_NV_to_IV(const NV nv, IV *ivp)
2607 /* This function determines if the input NV 'nv' may be converted without
2608 * loss of data to an IV. If not, it returns FALSE taking no other action.
2609 * But if it is possible, it does the conversion, returning TRUE, and
2610 * storing the converted result in '*ivp' */
2612 PERL_ARGS_ASSERT_LOSSLESS_NV_TO_IV;
2614 # if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
2615 /* Normally any comparison with a NaN returns false; if we can't rely
2616 * on that behaviour, check explicitly */
2617 if (UNLIKELY(Perl_isnan(nv))) {
2622 /* Written this way so that with an always-false NaN comparison we
2624 if (!(LIKELY(nv >= (NV) IV_MIN) && LIKELY(nv < IV_MAX_P1))) {
2628 if ((IV) nv != nv) {
2638 /* ------------------ pp.c, regcomp.c, toke.c, universal.c ------------ */
2640 #if defined(PERL_IN_PP_C) || defined(PERL_IN_REGCOMP_C) || defined(PERL_IN_TOKE_C) || defined(PERL_IN_UNIVERSAL_C)
2642 #define MAX_CHARSET_NAME_LENGTH 2
2644 PERL_STATIC_INLINE const char *
2645 S_get_regex_charset_name(const U32 flags, STRLEN* const lenp)
2647 PERL_ARGS_ASSERT_GET_REGEX_CHARSET_NAME;
2649 /* Returns a string that corresponds to the name of the regex character set
2650 * given by 'flags', and *lenp is set the length of that string, which
2651 * cannot exceed MAX_CHARSET_NAME_LENGTH characters */
2654 switch (get_regex_charset(flags)) {
2655 case REGEX_DEPENDS_CHARSET: return DEPENDS_PAT_MODS;
2656 case REGEX_LOCALE_CHARSET: return LOCALE_PAT_MODS;
2657 case REGEX_UNICODE_CHARSET: return UNICODE_PAT_MODS;
2658 case REGEX_ASCII_RESTRICTED_CHARSET: return ASCII_RESTRICT_PAT_MODS;
2659 case REGEX_ASCII_MORE_RESTRICTED_CHARSET:
2661 return ASCII_MORE_RESTRICT_PAT_MODS;
2663 /* The NOT_REACHED; hides an assert() which has a rather complex
2664 * definition in perl.h. */
2665 NOT_REACHED; /* NOTREACHED */
2666 return "?"; /* Unknown */
2673 Return false if any get magic is on the SV other than taint magic.
2677 PERL_STATIC_INLINE bool
2678 Perl_sv_only_taint_gmagic(SV *sv)
2680 MAGIC *mg = SvMAGIC(sv);
2682 PERL_ARGS_ASSERT_SV_ONLY_TAINT_GMAGIC;
2685 if (mg->mg_type != PERL_MAGIC_taint
2686 && !(mg->mg_flags & MGf_GSKIP)
2687 && mg->mg_virtual->svt_get) {
2690 mg = mg->mg_moremagic;
2696 /* ------------------ cop.h ------------------------------------------- */
2698 /* implement GIMME_V() macro */
2700 PERL_STATIC_INLINE U8
2704 U8 gimme = (PL_op->op_flags & OPf_WANT);
2708 cxix = PL_curstackinfo->si_cxsubix;
2710 return PL_curstackinfo->si_type == PERLSI_SORT ? G_SCALAR: G_VOID;
2711 assert(cxstack[cxix].blk_gimme & G_WANT);
2712 return (cxstack[cxix].blk_gimme & G_WANT);
2716 /* Enter a block. Push a new base context and return its address. */
2718 PERL_STATIC_INLINE PERL_CONTEXT *
2719 Perl_cx_pushblock(pTHX_ U8 type, U8 gimme, SV** sp, I32 saveix)
2723 PERL_ARGS_ASSERT_CX_PUSHBLOCK;
2728 cx->blk_gimme = gimme;
2729 cx->blk_oldsaveix = saveix;
2730 cx->blk_oldsp = (I32)(sp - PL_stack_base);
2731 cx->blk_oldcop = PL_curcop;
2732 cx->blk_oldmarksp = (I32)(PL_markstack_ptr - PL_markstack);
2733 cx->blk_oldscopesp = PL_scopestack_ix;
2734 cx->blk_oldpm = PL_curpm;
2735 cx->blk_old_tmpsfloor = PL_tmps_floor;
2737 PL_tmps_floor = PL_tmps_ix;
2738 CX_DEBUG(cx, "PUSH");
2743 /* Exit a block (RETURN and LAST). */
2745 PERL_STATIC_INLINE void
2746 Perl_cx_popblock(pTHX_ PERL_CONTEXT *cx)
2748 PERL_ARGS_ASSERT_CX_POPBLOCK;
2750 CX_DEBUG(cx, "POP");
2751 /* these 3 are common to cx_popblock and cx_topblock */
2752 PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp;
2753 PL_scopestack_ix = cx->blk_oldscopesp;
2754 PL_curpm = cx->blk_oldpm;
2756 /* LEAVE_SCOPE() should have made this true. /(?{})/ cheats
2757 * and leaves a CX entry lying around for repeated use, so
2758 * skip for multicall */ \
2759 assert( (CxTYPE(cx) == CXt_SUB && CxMULTICALL(cx))
2760 || PL_savestack_ix == cx->blk_oldsaveix);
2761 PL_curcop = cx->blk_oldcop;
2762 PL_tmps_floor = cx->blk_old_tmpsfloor;
2765 /* Continue a block elsewhere (e.g. NEXT, REDO, GOTO).
2766 * Whereas cx_popblock() restores the state to the point just before
2767 * cx_pushblock() was called, cx_topblock() restores it to the point just
2768 * *after* cx_pushblock() was called. */
2770 PERL_STATIC_INLINE void
2771 Perl_cx_topblock(pTHX_ PERL_CONTEXT *cx)
2773 PERL_ARGS_ASSERT_CX_TOPBLOCK;
2775 CX_DEBUG(cx, "TOP");
2776 /* these 3 are common to cx_popblock and cx_topblock */
2777 PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp;
2778 PL_scopestack_ix = cx->blk_oldscopesp;
2779 PL_curpm = cx->blk_oldpm;
2781 PL_stack_sp = PL_stack_base + cx->blk_oldsp;
2785 PERL_STATIC_INLINE void
2786 Perl_cx_pushsub(pTHX_ PERL_CONTEXT *cx, CV *cv, OP *retop, bool hasargs)
2788 U8 phlags = CX_PUSHSUB_GET_LVALUE_MASK(Perl_was_lvalue_sub);
2790 PERL_ARGS_ASSERT_CX_PUSHSUB;
2792 PERL_DTRACE_PROBE_ENTRY(cv);
2793 cx->blk_sub.old_cxsubix = PL_curstackinfo->si_cxsubix;
2794 PL_curstackinfo->si_cxsubix = cx - PL_curstackinfo->si_cxstack;
2795 cx->blk_sub.cv = cv;
2796 cx->blk_sub.olddepth = CvDEPTH(cv);
2797 cx->blk_sub.prevcomppad = PL_comppad;
2798 cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;
2799 cx->blk_sub.retop = retop;
2800 SvREFCNT_inc_simple_void_NN(cv);
2801 cx->blk_u16 = PL_op->op_private & (phlags|OPpDEREF);
2805 /* subsets of cx_popsub() */
2807 PERL_STATIC_INLINE void
2808 Perl_cx_popsub_common(pTHX_ PERL_CONTEXT *cx)
2812 PERL_ARGS_ASSERT_CX_POPSUB_COMMON;
2813 assert(CxTYPE(cx) == CXt_SUB);
2815 PL_comppad = cx->blk_sub.prevcomppad;
2816 PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;
2817 cv = cx->blk_sub.cv;
2818 CvDEPTH(cv) = cx->blk_sub.olddepth;
2819 cx->blk_sub.cv = NULL;
2821 PL_curstackinfo->si_cxsubix = cx->blk_sub.old_cxsubix;
2825 /* handle the @_ part of leaving a sub */
2827 PERL_STATIC_INLINE void
2828 Perl_cx_popsub_args(pTHX_ PERL_CONTEXT *cx)
2832 PERL_ARGS_ASSERT_CX_POPSUB_ARGS;
2833 assert(CxTYPE(cx) == CXt_SUB);
2834 assert(AvARRAY(MUTABLE_AV(
2835 PadlistARRAY(CvPADLIST(cx->blk_sub.cv))[
2836 CvDEPTH(cx->blk_sub.cv)])) == PL_curpad);
2838 CX_POP_SAVEARRAY(cx);
2839 av = MUTABLE_AV(PAD_SVl(0));
2840 if (UNLIKELY(AvREAL(av)))
2841 /* abandon @_ if it got reified */
2842 clear_defarray(av, 0);
2849 PERL_STATIC_INLINE void
2850 Perl_cx_popsub(pTHX_ PERL_CONTEXT *cx)
2852 PERL_ARGS_ASSERT_CX_POPSUB;
2853 assert(CxTYPE(cx) == CXt_SUB);
2855 PERL_DTRACE_PROBE_RETURN(cx->blk_sub.cv);
2859 cx_popsub_common(cx);
2863 PERL_STATIC_INLINE void
2864 Perl_cx_pushformat(pTHX_ PERL_CONTEXT *cx, CV *cv, OP *retop, GV *gv)
2866 PERL_ARGS_ASSERT_CX_PUSHFORMAT;
2868 cx->blk_format.old_cxsubix = PL_curstackinfo->si_cxsubix;
2869 PL_curstackinfo->si_cxsubix= cx - PL_curstackinfo->si_cxstack;
2870 cx->blk_format.cv = cv;
2871 cx->blk_format.retop = retop;
2872 cx->blk_format.gv = gv;
2873 cx->blk_format.dfoutgv = PL_defoutgv;
2874 cx->blk_format.prevcomppad = PL_comppad;
2877 SvREFCNT_inc_simple_void_NN(cv);
2879 SvREFCNT_inc_void(cx->blk_format.dfoutgv);
2883 PERL_STATIC_INLINE void
2884 Perl_cx_popformat(pTHX_ PERL_CONTEXT *cx)
2889 PERL_ARGS_ASSERT_CX_POPFORMAT;
2890 assert(CxTYPE(cx) == CXt_FORMAT);
2892 dfout = cx->blk_format.dfoutgv;
2894 cx->blk_format.dfoutgv = NULL;
2895 SvREFCNT_dec_NN(dfout);
2897 PL_comppad = cx->blk_format.prevcomppad;
2898 PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;
2899 cv = cx->blk_format.cv;
2900 cx->blk_format.cv = NULL;
2902 SvREFCNT_dec_NN(cv);
2903 PL_curstackinfo->si_cxsubix = cx->blk_format.old_cxsubix;
2907 PERL_STATIC_INLINE void
2908 Perl_push_evalortry_common(pTHX_ PERL_CONTEXT *cx, OP *retop, SV *namesv)
2910 cx->blk_eval.retop = retop;
2911 cx->blk_eval.old_namesv = namesv;
2912 cx->blk_eval.old_eval_root = PL_eval_root;
2913 cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;
2914 cx->blk_eval.cv = NULL; /* later set by doeval_compile() */
2915 cx->blk_eval.cur_top_env = PL_top_env;
2917 assert(!(PL_in_eval & ~ 0x3F));
2918 assert(!(PL_op->op_type & ~0x1FF));
2919 cx->blk_u16 = (PL_in_eval & 0x3F) | ((U16)PL_op->op_type << 7);
2922 PERL_STATIC_INLINE void
2923 Perl_cx_pusheval(pTHX_ PERL_CONTEXT *cx, OP *retop, SV *namesv)
2925 PERL_ARGS_ASSERT_CX_PUSHEVAL;
2927 Perl_push_evalortry_common(aTHX_ cx, retop, namesv);
2929 cx->blk_eval.old_cxsubix = PL_curstackinfo->si_cxsubix;
2930 PL_curstackinfo->si_cxsubix = cx - PL_curstackinfo->si_cxstack;
2933 PERL_STATIC_INLINE void
2934 Perl_cx_pushtry(pTHX_ PERL_CONTEXT *cx, OP *retop)
2936 PERL_ARGS_ASSERT_CX_PUSHTRY;
2938 Perl_push_evalortry_common(aTHX_ cx, retop, NULL);
2940 /* Don't actually change it, just store the current value so it's restored
2941 * by the common popeval */
2942 cx->blk_eval.old_cxsubix = PL_curstackinfo->si_cxsubix;
2946 PERL_STATIC_INLINE void
2947 Perl_cx_popeval(pTHX_ PERL_CONTEXT *cx)
2951 PERL_ARGS_ASSERT_CX_POPEVAL;
2952 assert(CxTYPE(cx) == CXt_EVAL);
2954 PL_in_eval = CxOLD_IN_EVAL(cx);
2955 assert(!(PL_in_eval & 0xc0));
2956 PL_eval_root = cx->blk_eval.old_eval_root;
2957 sv = cx->blk_eval.cur_text;
2958 if (sv && CxEVAL_TXT_REFCNTED(cx)) {
2959 cx->blk_eval.cur_text = NULL;
2960 SvREFCNT_dec_NN(sv);
2963 sv = cx->blk_eval.old_namesv;
2965 cx->blk_eval.old_namesv = NULL;
2966 SvREFCNT_dec_NN(sv);
2968 PL_curstackinfo->si_cxsubix = cx->blk_eval.old_cxsubix;
2972 /* push a plain loop, i.e.
2974 * while (cond) { block }
2975 * for (init;cond;continue) { block }
2976 * This loop can be last/redo'ed etc.
2979 PERL_STATIC_INLINE void
2980 Perl_cx_pushloop_plain(pTHX_ PERL_CONTEXT *cx)
2982 PERL_ARGS_ASSERT_CX_PUSHLOOP_PLAIN;
2983 cx->blk_loop.my_op = cLOOP;
2987 /* push a true for loop, i.e.
2988 * for var (list) { block }
2991 PERL_STATIC_INLINE void
2992 Perl_cx_pushloop_for(pTHX_ PERL_CONTEXT *cx, void *itervarp, SV* itersave)
2994 PERL_ARGS_ASSERT_CX_PUSHLOOP_FOR;
2996 /* this one line is common with cx_pushloop_plain */
2997 cx->blk_loop.my_op = cLOOP;
2999 cx->blk_loop.itervar_u.svp = (SV**)itervarp;
3000 cx->blk_loop.itersave = itersave;
3002 cx->blk_loop.oldcomppad = PL_comppad;
3007 /* pop all loop types, including plain */
3009 PERL_STATIC_INLINE void
3010 Perl_cx_poploop(pTHX_ PERL_CONTEXT *cx)
3012 PERL_ARGS_ASSERT_CX_POPLOOP;
3014 assert(CxTYPE_is_LOOP(cx));
3015 if ( CxTYPE(cx) == CXt_LOOP_ARY
3016 || CxTYPE(cx) == CXt_LOOP_LAZYSV)
3018 /* Free ary or cur. This assumes that state_u.ary.ary
3019 * aligns with state_u.lazysv.cur. See cx_dup() */
3020 SV *sv = cx->blk_loop.state_u.lazysv.cur;
3021 cx->blk_loop.state_u.lazysv.cur = NULL;
3022 SvREFCNT_dec_NN(sv);
3023 if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {
3024 sv = cx->blk_loop.state_u.lazysv.end;
3025 cx->blk_loop.state_u.lazysv.end = NULL;
3026 SvREFCNT_dec_NN(sv);
3029 if (cx->cx_type & (CXp_FOR_PAD|CXp_FOR_GV)) {
3031 SV **svp = (cx)->blk_loop.itervar_u.svp;
3032 if ((cx->cx_type & CXp_FOR_GV))
3033 svp = &GvSV((GV*)svp);
3035 *svp = cx->blk_loop.itersave;
3036 cx->blk_loop.itersave = NULL;
3037 SvREFCNT_dec(cursv);
3042 PERL_STATIC_INLINE void
3043 Perl_cx_pushwhen(pTHX_ PERL_CONTEXT *cx)
3045 PERL_ARGS_ASSERT_CX_PUSHWHEN;
3047 cx->blk_givwhen.leave_op = cLOGOP->op_other;
3051 PERL_STATIC_INLINE void
3052 Perl_cx_popwhen(pTHX_ PERL_CONTEXT *cx)
3054 PERL_ARGS_ASSERT_CX_POPWHEN;
3055 assert(CxTYPE(cx) == CXt_WHEN);
3057 PERL_UNUSED_ARG(cx);
3058 PERL_UNUSED_CONTEXT;
3059 /* currently NOOP */
3063 PERL_STATIC_INLINE void
3064 Perl_cx_pushgiven(pTHX_ PERL_CONTEXT *cx, SV *orig_defsv)
3066 PERL_ARGS_ASSERT_CX_PUSHGIVEN;
3068 cx->blk_givwhen.leave_op = cLOGOP->op_other;
3069 cx->blk_givwhen.defsv_save = orig_defsv;
3073 PERL_STATIC_INLINE void
3074 Perl_cx_popgiven(pTHX_ PERL_CONTEXT *cx)
3078 PERL_ARGS_ASSERT_CX_POPGIVEN;
3079 assert(CxTYPE(cx) == CXt_GIVEN);
3081 sv = GvSV(PL_defgv);
3082 GvSV(PL_defgv) = cx->blk_givwhen.defsv_save;
3083 cx->blk_givwhen.defsv_save = NULL;
3087 /* ------------------ util.h ------------------------------------------- */
3090 =for apidoc_section $string
3094 Returns true if the leading C<len> bytes of the strings C<s1> and C<s2> are the
3096 case-insensitively; false otherwise. Uppercase and lowercase ASCII range bytes
3097 match themselves and their opposite case counterparts. Non-cased and non-ASCII
3098 range bytes match only themselves.
3103 PERL_STATIC_INLINE I32
3104 Perl_foldEQ(const char *s1, const char *s2, I32 len)
3106 const U8 *a = (const U8 *)s1;
3107 const U8 *b = (const U8 *)s2;
3109 PERL_ARGS_ASSERT_FOLDEQ;
3114 if (*a != *b && *a != PL_fold[*b])
3121 PERL_STATIC_INLINE I32
3122 Perl_foldEQ_latin1(const char *s1, const char *s2, I32 len)
3124 /* Compare non-UTF-8 using Unicode (Latin1) semantics. Works on all folds
3125 * representable without UTF-8, except for LATIN_SMALL_LETTER_SHARP_S, and
3126 * does not check for this. Nor does it check that the strings each have
3127 * at least 'len' characters. */
3129 const U8 *a = (const U8 *)s1;
3130 const U8 *b = (const U8 *)s2;
3132 PERL_ARGS_ASSERT_FOLDEQ_LATIN1;
3137 if (*a != *b && *a != PL_fold_latin1[*b]) {
3146 =for apidoc_section $locale
3147 =for apidoc foldEQ_locale
3149 Returns true if the leading C<len> bytes of the strings C<s1> and C<s2> are the
3150 same case-insensitively in the current locale; false otherwise.
3155 PERL_STATIC_INLINE I32
3156 Perl_foldEQ_locale(const char *s1, const char *s2, I32 len)
3158 const U8 *a = (const U8 *)s1;
3159 const U8 *b = (const U8 *)s2;
3161 PERL_ARGS_ASSERT_FOLDEQ_LOCALE;
3166 if (*a != *b && *a != PL_fold_locale[*b])
3174 =for apidoc_section $string
3175 =for apidoc my_strnlen
3177 The C library C<strnlen> if available, or a Perl implementation of it.
3179 C<my_strnlen()> computes the length of the string, up to C<maxlen>
3180 characters. It will never attempt to address more than C<maxlen>
3181 characters, making it suitable for use with strings that are not
3182 guaranteed to be NUL-terminated.
3186 Description stolen from http://man.openbsd.org/strnlen.3,
3187 implementation stolen from PostgreSQL.
3191 PERL_STATIC_INLINE Size_t
3192 Perl_my_strnlen(const char *str, Size_t maxlen)
3194 const char *end = (char *) memchr(str, '\0', maxlen);
3196 PERL_ARGS_ASSERT_MY_STRNLEN;
3198 if (end == NULL) return maxlen;
3204 #if ! defined (HAS_MEMRCHR) && (defined(PERL_CORE) || defined(PERL_EXT))
3206 PERL_STATIC_INLINE void *
3207 S_my_memrchr(const char * s, const char c, const STRLEN len)
3209 /* memrchr(), since many platforms lack it */
3211 const char * t = s + len - 1;
3213 PERL_ARGS_ASSERT_MY_MEMRCHR;
3227 PERL_STATIC_INLINE char *
3228 Perl_mortal_getenv(const char * str)
3230 /* This implements a (mostly) thread-safe, sequential-call-safe getenv().
3232 * It's (mostly) thread-safe because it uses a mutex to prevent other
3233 * threads (that look at this mutex) from destroying the result before this
3234 * routine has a chance to copy the result to a place that won't be
3235 * destroyed before the caller gets a chance to handle it. That place is a
3236 * mortal SV. khw chose this over SAVEFREEPV because he is under the
3237 * impression that the SV will hang around longer under more circumstances
3239 * The reason it isn't completely thread-safe is that other code could
3240 * simply not pay attention to the mutex. All of the Perl core uses the
3241 * mutex, but it is possible for code from, say XS, to not use this mutex,
3242 * defeating the safety.
3244 * getenv() returns, in some implementations, a pointer to a spot in the
3245 * **environ array, which could be invalidated at any time by this or
3246 * another thread changing the environment. Other implementations copy the
3247 * **environ value to a static buffer, returning a pointer to that. That
3248 * buffer might or might not be invalidated by a getenv() call in another
3249 * thread. If it does get zapped, we need an exclusive lock. Otherwise,
3250 * many getenv() calls can safely be running simultaneously, so a
3251 * many-reader (but no simultaneous writers) lock is ok. There is a
3252 * Configure probe to see if another thread destroys the buffer, and the
3253 * mutex is defined accordingly.
3255 * But in all cases, using the mutex prevents these problems, as long as
3256 * all code uses the same mutex..
3258 * A complication is that this can be called during phases where the
3259 * mortalization process isn't available. These are in interpreter
3260 * destruction or early in construction. khw believes that at these times
3261 * there shouldn't be anything else going on, so plain getenv is safe AS
3262 * LONG AS the caller acts on the return before calling it again. */
3267 PERL_ARGS_ASSERT_MORTAL_GETENV;
3269 /* Can't mortalize without stacks. khw believes that no other threads
3270 * should be running, so no need to lock things, and this may be during a
3271 * phase when locking isn't even available */
3272 if (UNLIKELY(PL_scopestack_ix == 0)) {
3278 /* A major complication arises under PERL_MEM_LOG. When that is active,
3279 * every memory allocation may result in logging, depending on the value of
3280 * ENV{PERL_MEM_LOG} at the moment. That means, as we create the SV for
3281 * saving ENV{foo}'s value (but before saving it), the logging code will
3282 * call us recursively to find out what ENV{PERL_MEM_LOG} is. Without some
3283 * care that could lead to: 1) infinite recursion; or 2) deadlock (trying to
3284 * lock a boolean mutex recursively); 3) destroying the getenv() static
3285 * buffer; or 4) destroying the temporary created by this for the copy
3286 * causes a log entry to be made which could cause a new temporary to be
3287 * created, which will need to be destroyed at some point, leading to an
3290 * The solution adopted here (after some gnashing of teeth) is to detect
3291 * the recursive calls and calls from the logger, and treat them specially.
3292 * Let's say we want to do getenv("foo"). We first find
3293 * getenv(PERL_MEM_LOG) and save it to a fixed-length per-interpreter
3294 * variable, so no temporary is required. Then we do getenv(foo}, and in
3295 * the process of creating a temporary to save it, this function will be
3296 * called recursively to do a getenv(PERL_MEM_LOG). On the recursed call,
3297 * we detect that it is such a call and return our saved value instead of
3298 * locking and doing a new getenv(). This solves all of problems 1), 2),
3299 * and 3). Because all the getenv()s are done while the mutex is locked,
3300 * the state cannot have changed. To solve 4), we don't create a temporary
3301 * when this is called from the logging code. That code disposes of the
3302 * return value while the mutex is still locked.
3304 * The value of getenv(PERL_MEM_LOG) can be anything, but only initial
3305 * digits and 3 particular letters are significant; the rest are ignored by
3306 * the memory logging code. Thus the per-interpreter variable only needs
3307 * to be large enough to save the significant information, the size of
3308 * which is known at compile time. The first byte is extra, reserved for
3309 * flags for our use. To protect against overflowing, only the reserved
3310 * byte, as many digits as don't overflow, and the three letters are
3313 * The reserved byte has two bits:
3314 * 0x1 if set indicates that if we get here, it is a recursive call of
3316 * 0x2 if set indicates that the call is from the logging code.
3318 * If the flag indicates this is a recursive call, just return the stored
3319 * value of PL_mem_log; An empty value gets turned into NULL. */
3320 if (strEQ(str, "PERL_MEM_LOG") && PL_mem_log[0] & 0x1) {
3321 if (PL_mem_log[1] == '\0') {
3324 return PL_mem_log + 1;
3334 /* Here we are in a critical section. As explained above, we do our own
3335 * getenv(PERL_MEM_LOG), saving the result safely. */
3336 ret = getenv("PERL_MEM_LOG");
3337 if (ret == NULL) { /* No logging active */
3339 /* Return that immediately if called from the logging code */
3340 if (PL_mem_log[0] & 0x2) {
3345 PL_mem_log[1] = '\0';
3348 char *mem_log_meat = PL_mem_log + 1; /* first byte reserved */
3350 /* There is nothing to prevent the value of PERL_MEM_LOG from being an
3351 * extremely long string. But we want only a few characters from it.
3352 * PL_mem_log has been made large enough to hold just the ones we need.
3353 * First the file descriptor. */
3354 if (isDIGIT(*ret)) {
3355 const char * s = ret;
3356 if (UNLIKELY(*s == '0')) {
3358 /* Reduce multiple leading zeros to a single one. This is to
3359 * allow the caller to change what to do with leading zeros. */
3360 *mem_log_meat++ = '0';
3367 /* If the input overflows, copy just enough for the result to also
3368 * overflow, plus 1 to make sure */
3369 while (isDIGIT(*s) && s < ret + TYPE_DIGITS(UV) + 1) {
3370 *mem_log_meat++ = *s++;
3374 /* Then each of the three significant characters */
3375 if (strchr(ret, 'm')) {
3376 *mem_log_meat++ = 'm';
3378 if (strchr(ret, 's')) {
3379 *mem_log_meat++ = 's';
3381 if (strchr(ret, 't')) {
3382 *mem_log_meat++ = 't';
3384 *mem_log_meat = '\0';
3386 assert(mem_log_meat < PL_mem_log + sizeof(PL_mem_log));
3389 /* If we are being called from the logger, it only needs the significant
3390 * portion of PERL_MEM_LOG, and doesn't need a safe copy */
3391 if (PL_mem_log[0] & 0x2) {
3392 assert(strEQ(str, "PERL_MEM_LOG"));
3394 return PL_mem_log + 1;
3397 /* Here is a generic getenv(). This could be a getenv("PERL_MEM_LOG") that
3398 * is coming from other than the logging code, so it should be treated the
3399 * same as any other getenv(), returning the full value, not just the
3400 * significant part, and having its value saved. Set the flag that
3401 * indicates any call to this routine will be a recursion from here */
3402 PL_mem_log[0] = 0x1;
3406 /* Now get the value of the real desired variable, and save a copy */
3410 ret = SvPVX( newSVpvn_flags(ret, strlen(ret) ,SVs_TEMP) );
3417 /* Clear the buffer */
3418 Zero(PL_mem_log, sizeof(PL_mem_log), char);
3425 PERL_STATIC_INLINE bool
3426 Perl_sv_isbool(pTHX_ const SV *sv)
3428 return SvIOK(sv) && SvPOK(sv) && SvIsCOW_static(sv) &&
3429 (SvPVX_const(sv) == PL_Yes || SvPVX_const(sv) == PL_No);
3434 PERL_STATIC_INLINE AV *
3435 Perl_cop_file_avn(pTHX_ const COP *cop) {
3437 PERL_ARGS_ASSERT_COP_FILE_AVN;
3439 const char *file = CopFILE(cop);
3441 GV *gv = gv_fetchfile_flags(file, strlen(file), GVF_NOADD);
3455 * ex: set ts=8 sts=4 sw=4 et: