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util.c
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util.c
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/* util.c
*
* Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
* 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
*
*/
/*
* 'Very useful, no doubt, that was to Saruman; yet it seems that he was
* not content.' --Gandalf to Pippin
*
* [p.598 of _The Lord of the Rings_, III/xi: "The Palantír"]
*/
/* This file contains assorted utility routines.
* Which is a polite way of saying any stuff that people couldn't think of
* a better place for. Amongst other things, it includes the warning and
* dieing stuff, plus wrappers for malloc code.
*/
#include "EXTERN.h"
#define PERL_IN_UTIL_C
#include "perl.h"
#include "reentr.h"
#ifdef USE_PERLIO
#include "perliol.h" /* For PerlIOUnix_refcnt */
#endif
#ifndef PERL_MICRO
#include <signal.h>
#ifndef SIG_ERR
# define SIG_ERR ((Sighandler_t) -1)
#endif
#endif
#ifdef __Lynx__
/* Missing protos on LynxOS */
int putenv(char *);
#endif
#ifdef HAS_SELECT
# ifdef I_SYS_SELECT
# include <sys/select.h>
# endif
#endif
#define FLUSH
#if defined(HAS_FCNTL) && defined(F_SETFD) && !defined(FD_CLOEXEC)
# define FD_CLOEXEC 1 /* NeXT needs this */
#endif
/* NOTE: Do not call the next three routines directly. Use the macros
* in handy.h, so that we can easily redefine everything to do tracking of
* allocated hunks back to the original New to track down any memory leaks.
* XXX This advice seems to be widely ignored :-( --AD August 1996.
*/
#if defined (DEBUGGING) || defined(PERL_IMPLICIT_SYS) || defined (PERL_TRACK_MEMPOOL)
# define ALWAYS_NEED_THX
#endif
/* paranoid version of system's malloc() */
Malloc_t
Perl_safesysmalloc(MEM_SIZE size)
{
#ifdef ALWAYS_NEED_THX
dTHX;
#endif
Malloc_t ptr;
#ifdef HAS_64K_LIMIT
if (size > 0xffff) {
PerlIO_printf(Perl_error_log,
"Allocation too large: %lx\n", size) FLUSH;
my_exit(1);
}
#endif /* HAS_64K_LIMIT */
#ifdef PERL_TRACK_MEMPOOL
size += sTHX;
#endif
#ifdef DEBUGGING
if ((SSize_t)size < 0)
Perl_croak_nocontext("panic: malloc, size=%"UVuf, (UV) size);
#endif
ptr = (Malloc_t)PerlMem_malloc(size?size:1); /* malloc(0) is NASTY on our system */
PERL_ALLOC_CHECK(ptr);
if (ptr != NULL) {
#ifdef PERL_TRACK_MEMPOOL
struct perl_memory_debug_header *const header
= (struct perl_memory_debug_header *)ptr;
#endif
#ifdef PERL_POISON
PoisonNew(((char *)ptr), size, char);
#endif
#ifdef PERL_TRACK_MEMPOOL
header->interpreter = aTHX;
/* Link us into the list. */
header->prev = &PL_memory_debug_header;
header->next = PL_memory_debug_header.next;
PL_memory_debug_header.next = header;
header->next->prev = header;
# ifdef PERL_POISON
header->size = size;
# endif
ptr = (Malloc_t)((char*)ptr+sTHX);
#endif
DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) malloc %ld bytes\n",PTR2UV(ptr),(long)PL_an++,(long)size));
return ptr;
}
else {
#ifndef ALWAYS_NEED_THX
dTHX;
#endif
if (PL_nomemok)
return NULL;
else {
croak_no_mem();
}
}
/*NOTREACHED*/
}
/* paranoid version of system's realloc() */
Malloc_t
Perl_safesysrealloc(Malloc_t where,MEM_SIZE size)
{
#ifdef ALWAYS_NEED_THX
dTHX;
#endif
Malloc_t ptr;
#if !defined(STANDARD_C) && !defined(HAS_REALLOC_PROTOTYPE) && !defined(PERL_MICRO)
Malloc_t PerlMem_realloc();
#endif /* !defined(STANDARD_C) && !defined(HAS_REALLOC_PROTOTYPE) */
#ifdef HAS_64K_LIMIT
if (size > 0xffff) {
PerlIO_printf(Perl_error_log,
"Reallocation too large: %lx\n", size) FLUSH;
my_exit(1);
}
#endif /* HAS_64K_LIMIT */
if (!size) {
safesysfree(where);
return NULL;
}
if (!where)
return safesysmalloc(size);
#ifdef PERL_TRACK_MEMPOOL
where = (Malloc_t)((char*)where-sTHX);
size += sTHX;
{
struct perl_memory_debug_header *const header
= (struct perl_memory_debug_header *)where;
if (header->interpreter != aTHX) {
Perl_croak_nocontext("panic: realloc from wrong pool, %p!=%p",
header->interpreter, aTHX);
}
assert(header->next->prev == header);
assert(header->prev->next == header);
# ifdef PERL_POISON
if (header->size > size) {
const MEM_SIZE freed_up = header->size - size;
char *start_of_freed = ((char *)where) + size;
PoisonFree(start_of_freed, freed_up, char);
}
header->size = size;
# endif
}
#endif
#ifdef DEBUGGING
if ((SSize_t)size < 0)
Perl_croak_nocontext("panic: realloc, size=%"UVuf, (UV)size);
#endif
ptr = (Malloc_t)PerlMem_realloc(where,size);
PERL_ALLOC_CHECK(ptr);
/* MUST do this fixup first, before doing ANYTHING else, as anything else
might allocate memory/free/move memory, and until we do the fixup, it
may well be chasing (and writing to) free memory. */
#ifdef PERL_TRACK_MEMPOOL
if (ptr != NULL) {
struct perl_memory_debug_header *const header
= (struct perl_memory_debug_header *)ptr;
# ifdef PERL_POISON
if (header->size < size) {
const MEM_SIZE fresh = size - header->size;
char *start_of_fresh = ((char *)ptr) + size;
PoisonNew(start_of_fresh, fresh, char);
}
# endif
header->next->prev = header;
header->prev->next = header;
ptr = (Malloc_t)((char*)ptr+sTHX);
}
#endif
/* In particular, must do that fixup above before logging anything via
*printf(), as it can reallocate memory, which can cause SEGVs. */
DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) rfree\n",PTR2UV(where),(long)PL_an++));
DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) realloc %ld bytes\n",PTR2UV(ptr),(long)PL_an++,(long)size));
if (ptr != NULL) {
return ptr;
}
else {
#ifndef ALWAYS_NEED_THX
dTHX;
#endif
if (PL_nomemok)
return NULL;
else {
croak_no_mem();
}
}
/*NOTREACHED*/
}
/* safe version of system's free() */
Free_t
Perl_safesysfree(Malloc_t where)
{
#ifdef ALWAYS_NEED_THX
dTHX;
#else
dVAR;
#endif
DEBUG_m( PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) free\n",PTR2UV(where),(long)PL_an++));
if (where) {
#ifdef PERL_TRACK_MEMPOOL
where = (Malloc_t)((char*)where-sTHX);
{
struct perl_memory_debug_header *const header
= (struct perl_memory_debug_header *)where;
if (header->interpreter != aTHX) {
Perl_croak_nocontext("panic: free from wrong pool, %p!=%p",
header->interpreter, aTHX);
}
if (!header->prev) {
Perl_croak_nocontext("panic: duplicate free");
}
if (!(header->next))
Perl_croak_nocontext("panic: bad free, header->next==NULL");
if (header->next->prev != header || header->prev->next != header) {
Perl_croak_nocontext("panic: bad free, ->next->prev=%p, "
"header=%p, ->prev->next=%p",
header->next->prev, header,
header->prev->next);
}
/* Unlink us from the chain. */
header->next->prev = header->prev;
header->prev->next = header->next;
# ifdef PERL_POISON
PoisonNew(where, header->size, char);
# endif
/* Trigger the duplicate free warning. */
header->next = NULL;
}
#endif
PerlMem_free(where);
}
}
/* safe version of system's calloc() */
Malloc_t
Perl_safesyscalloc(MEM_SIZE count, MEM_SIZE size)
{
#ifdef ALWAYS_NEED_THX
dTHX;
#endif
Malloc_t ptr;
#if defined(PERL_TRACK_MEMPOOL) || defined(HAS_64K_LIMIT) || defined(DEBUGGING)
MEM_SIZE total_size = 0;
#endif
/* Even though calloc() for zero bytes is strange, be robust. */
if (size && (count <= MEM_SIZE_MAX / size)) {
#if defined(PERL_TRACK_MEMPOOL) || defined(HAS_64K_LIMIT) || defined(DEBUGGING)
total_size = size * count;
#endif
}
else
croak_memory_wrap();
#ifdef PERL_TRACK_MEMPOOL
if (sTHX <= MEM_SIZE_MAX - (MEM_SIZE)total_size)
total_size += sTHX;
else
croak_memory_wrap();
#endif
#ifdef HAS_64K_LIMIT
if (total_size > 0xffff) {
PerlIO_printf(Perl_error_log,
"Allocation too large: %lx\n", total_size) FLUSH;
my_exit(1);
}
#endif /* HAS_64K_LIMIT */
#ifdef DEBUGGING
if ((SSize_t)size < 0 || (SSize_t)count < 0)
Perl_croak_nocontext("panic: calloc, size=%"UVuf", count=%"UVuf,
(UV)size, (UV)count);
#endif
#ifdef PERL_TRACK_MEMPOOL
/* Have to use malloc() because we've added some space for our tracking
header. */
/* malloc(0) is non-portable. */
ptr = (Malloc_t)PerlMem_malloc(total_size ? total_size : 1);
#else
/* Use calloc() because it might save a memset() if the memory is fresh
and clean from the OS. */
if (count && size)
ptr = (Malloc_t)PerlMem_calloc(count, size);
else /* calloc(0) is non-portable. */
ptr = (Malloc_t)PerlMem_calloc(count ? count : 1, size ? size : 1);
#endif
PERL_ALLOC_CHECK(ptr);
DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) calloc %ld x %ld bytes\n",PTR2UV(ptr),(long)PL_an++,(long)count,(long)total_size));
if (ptr != NULL) {
#ifdef PERL_TRACK_MEMPOOL
{
struct perl_memory_debug_header *const header
= (struct perl_memory_debug_header *)ptr;
memset((void*)ptr, 0, total_size);
header->interpreter = aTHX;
/* Link us into the list. */
header->prev = &PL_memory_debug_header;
header->next = PL_memory_debug_header.next;
PL_memory_debug_header.next = header;
header->next->prev = header;
# ifdef PERL_POISON
header->size = total_size;
# endif
ptr = (Malloc_t)((char*)ptr+sTHX);
}
#endif
return ptr;
}
else {
#ifndef ALWAYS_NEED_THX
dTHX;
#endif
if (PL_nomemok)
return NULL;
croak_no_mem();
}
}
/* These must be defined when not using Perl's malloc for binary
* compatibility */
#ifndef MYMALLOC
Malloc_t Perl_malloc (MEM_SIZE nbytes)
{
dTHXs;
return (Malloc_t)PerlMem_malloc(nbytes);
}
Malloc_t Perl_calloc (MEM_SIZE elements, MEM_SIZE size)
{
dTHXs;
return (Malloc_t)PerlMem_calloc(elements, size);
}
Malloc_t Perl_realloc (Malloc_t where, MEM_SIZE nbytes)
{
dTHXs;
return (Malloc_t)PerlMem_realloc(where, nbytes);
}
Free_t Perl_mfree (Malloc_t where)
{
dTHXs;
PerlMem_free(where);
}
#endif
/* copy a string up to some (non-backslashed) delimiter, if any */
char *
Perl_delimcpy(char *to, const char *toend, const char *from, const char *fromend, int delim, I32 *retlen)
{
I32 tolen;
PERL_ARGS_ASSERT_DELIMCPY;
for (tolen = 0; from < fromend; from++, tolen++) {
if (*from == '\\') {
if (from[1] != delim) {
if (to < toend)
*to++ = *from;
tolen++;
}
from++;
}
else if (*from == delim)
break;
if (to < toend)
*to++ = *from;
}
if (to < toend)
*to = '\0';
*retlen = tolen;
return (char *)from;
}
/* return ptr to little string in big string, NULL if not found */
/* This routine was donated by Corey Satten. */
char *
Perl_instr(const char *big, const char *little)
{
PERL_ARGS_ASSERT_INSTR;
/* libc prior to 4.6.27 did not work properly on a NULL 'little' */
if (!little)
return (char*)big;
return strstr((char*)big, (char*)little);
}
/* same as instr but allow embedded nulls. The end pointers point to 1 beyond
* the final character desired to be checked */
char *
Perl_ninstr(const char *big, const char *bigend, const char *little, const char *lend)
{
PERL_ARGS_ASSERT_NINSTR;
if (little >= lend)
return (char*)big;
{
const char first = *little;
const char *s, *x;
bigend -= lend - little++;
OUTER:
while (big <= bigend) {
if (*big++ == first) {
for (x=big,s=little; s < lend; x++,s++) {
if (*s != *x)
goto OUTER;
}
return (char*)(big-1);
}
}
}
return NULL;
}
/* reverse of the above--find last substring */
char *
Perl_rninstr(const char *big, const char *bigend, const char *little, const char *lend)
{
const char *bigbeg;
const I32 first = *little;
const char * const littleend = lend;
PERL_ARGS_ASSERT_RNINSTR;
if (little >= littleend)
return (char*)bigend;
bigbeg = big;
big = bigend - (littleend - little++);
while (big >= bigbeg) {
const char *s, *x;
if (*big-- != first)
continue;
for (x=big+2,s=little; s < littleend; /**/ ) {
if (*s != *x)
break;
else {
x++;
s++;
}
}
if (s >= littleend)
return (char*)(big+1);
}
return NULL;
}
/* As a space optimization, we do not compile tables for strings of length
0 and 1, and for strings of length 2 unless FBMcf_TAIL. These are
special-cased in fbm_instr().
If FBMcf_TAIL, the table is created as if the string has a trailing \n. */
/*
=head1 Miscellaneous Functions
=for apidoc fbm_compile
Analyses the string in order to make fast searches on it using fbm_instr()
-- the Boyer-Moore algorithm.
=cut
*/
void
Perl_fbm_compile(pTHX_ SV *sv, U32 flags)
{
dVAR;
const U8 *s;
STRLEN i;
STRLEN len;
STRLEN rarest = 0;
U32 frequency = 256;
MAGIC *mg;
PERL_ARGS_ASSERT_FBM_COMPILE;
if (isGV_with_GP(sv))
return;
if (SvVALID(sv))
return;
if (flags & FBMcf_TAIL) {
MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ? mg_find(sv, PERL_MAGIC_utf8) : NULL;
sv_catpvs(sv, "\n"); /* Taken into account in fbm_instr() */
if (mg && mg->mg_len >= 0)
mg->mg_len++;
}
s = (U8*)SvPV_force_mutable(sv, len);
if (len == 0) /* TAIL might be on a zero-length string. */
return;
SvUPGRADE(sv, SVt_PVMG);
SvIOK_off(sv);
SvNOK_off(sv);
SvVALID_on(sv);
/* "deep magic", the comment used to add. The use of MAGIC itself isn't
really. MAGIC was originally added in 79072805bf63abe5 (perl 5.0 alpha 2)
to call SvVALID_off() if the scalar was assigned to.
The comment itself (and "deeper magic" below) date back to
378cc40b38293ffc (perl 2.0). "deep magic" was an annotation on
str->str_pok |= 2;
where the magic (presumably) was that the scalar had a BM table hidden
inside itself.
As MAGIC is always present on BMs [in Perl 5 :-)], we can use it to store
the table instead of the previous (somewhat hacky) approach of co-opting
the string buffer and storing it after the string. */
assert(!mg_find(sv, PERL_MAGIC_bm));
mg = sv_magicext(sv, NULL, PERL_MAGIC_bm, &PL_vtbl_bm, NULL, 0);
assert(mg);
if (len > 2) {
/* Shorter strings are special-cased in Perl_fbm_instr(), and don't use
the BM table. */
const U8 mlen = (len>255) ? 255 : (U8)len;
const unsigned char *const sb = s + len - mlen; /* first char (maybe) */
U8 *table;
Newx(table, 256, U8);
memset((void*)table, mlen, 256);
mg->mg_ptr = (char *)table;
mg->mg_len = 256;
s += len - 1; /* last char */
i = 0;
while (s >= sb) {
if (table[*s] == mlen)
table[*s] = (U8)i;
s--, i++;
}
}
s = (const unsigned char*)(SvPVX_const(sv)); /* deeper magic */
for (i = 0; i < len; i++) {
if (PL_freq[s[i]] < frequency) {
rarest = i;
frequency = PL_freq[s[i]];
}
}
BmRARE(sv) = s[rarest];
BmPREVIOUS(sv) = rarest;
BmUSEFUL(sv) = 100; /* Initial value */
if (flags & FBMcf_TAIL)
SvTAIL_on(sv);
DEBUG_r(PerlIO_printf(Perl_debug_log, "rarest char %c at %"UVuf"\n",
BmRARE(sv), BmPREVIOUS(sv)));
}
/* If SvTAIL(littlestr), it has a fake '\n' at end. */
/* If SvTAIL is actually due to \Z or \z, this gives false positives
if multiline */
/*
=for apidoc fbm_instr
Returns the location of the SV in the string delimited by C<big> and
C<bigend>. It returns C<NULL> if the string can't be found. The C<sv>
does not have to be fbm_compiled, but the search will not be as fast
then.
=cut
*/
char *
Perl_fbm_instr(pTHX_ unsigned char *big, unsigned char *bigend, SV *littlestr, U32 flags)
{
unsigned char *s;
STRLEN l;
const unsigned char *little = (const unsigned char *)SvPV_const(littlestr,l);
STRLEN littlelen = l;
const I32 multiline = flags & FBMrf_MULTILINE;
PERL_ARGS_ASSERT_FBM_INSTR;
if ((STRLEN)(bigend - big) < littlelen) {
if ( SvTAIL(littlestr)
&& ((STRLEN)(bigend - big) == littlelen - 1)
&& (littlelen == 1
|| (*big == *little &&
memEQ((char *)big, (char *)little, littlelen - 1))))
return (char*)big;
return NULL;
}
switch (littlelen) { /* Special cases for 0, 1 and 2 */
case 0:
return (char*)big; /* Cannot be SvTAIL! */
case 1:
if (SvTAIL(littlestr) && !multiline) { /* Anchor only! */
/* Know that bigend != big. */
if (bigend[-1] == '\n')
return (char *)(bigend - 1);
return (char *) bigend;
}
s = big;
while (s < bigend) {
if (*s == *little)
return (char *)s;
s++;
}
if (SvTAIL(littlestr))
return (char *) bigend;
return NULL;
case 2:
if (SvTAIL(littlestr) && !multiline) {
if (bigend[-1] == '\n' && bigend[-2] == *little)
return (char*)bigend - 2;
if (bigend[-1] == *little)
return (char*)bigend - 1;
return NULL;
}
{
/* This should be better than FBM if c1 == c2, and almost
as good otherwise: maybe better since we do less indirection.
And we save a lot of memory by caching no table. */
const unsigned char c1 = little[0];
const unsigned char c2 = little[1];
s = big + 1;
bigend--;
if (c1 != c2) {
while (s <= bigend) {
if (s[0] == c2) {
if (s[-1] == c1)
return (char*)s - 1;
s += 2;
continue;
}
next_chars:
if (s[0] == c1) {
if (s == bigend)
goto check_1char_anchor;
if (s[1] == c2)
return (char*)s;
else {
s++;
goto next_chars;
}
}
else
s += 2;
}
goto check_1char_anchor;
}
/* Now c1 == c2 */
while (s <= bigend) {
if (s[0] == c1) {
if (s[-1] == c1)
return (char*)s - 1;
if (s == bigend)
goto check_1char_anchor;
if (s[1] == c1)
return (char*)s;
s += 3;
}
else
s += 2;
}
}
check_1char_anchor: /* One char and anchor! */
if (SvTAIL(littlestr) && (*bigend == *little))
return (char *)bigend; /* bigend is already decremented. */
return NULL;
default:
break; /* Only lengths 0 1 and 2 have special-case code. */
}
if (SvTAIL(littlestr) && !multiline) { /* tail anchored? */
s = bigend - littlelen;
if (s >= big && bigend[-1] == '\n' && *s == *little
/* Automatically of length > 2 */
&& memEQ((char*)s + 1, (char*)little + 1, littlelen - 2))
{
return (char*)s; /* how sweet it is */
}
if (s[1] == *little
&& memEQ((char*)s + 2, (char*)little + 1, littlelen - 2))
{
return (char*)s + 1; /* how sweet it is */
}
return NULL;
}
if (!SvVALID(littlestr)) {
char * const b = ninstr((char*)big,(char*)bigend,
(char*)little, (char*)little + littlelen);
if (!b && SvTAIL(littlestr)) { /* Automatically multiline! */
/* Chop \n from littlestr: */
s = bigend - littlelen + 1;
if (*s == *little
&& memEQ((char*)s + 1, (char*)little + 1, littlelen - 2))
{
return (char*)s;
}
return NULL;
}
return b;
}
/* Do actual FBM. */
if (littlelen > (STRLEN)(bigend - big))
return NULL;
{
const MAGIC *const mg = mg_find(littlestr, PERL_MAGIC_bm);
const unsigned char * const table = (const unsigned char *) mg->mg_ptr;
const unsigned char *oldlittle;
--littlelen; /* Last char found by table lookup */
s = big + littlelen;
little += littlelen; /* last char */
oldlittle = little;
if (s < bigend) {
I32 tmp;
top2:
if ((tmp = table[*s])) {
if ((s += tmp) < bigend)
goto top2;
goto check_end;
}
else { /* less expensive than calling strncmp() */
unsigned char * const olds = s;
tmp = littlelen;
while (tmp--) {
if (*--s == *--little)
continue;
s = olds + 1; /* here we pay the price for failure */
little = oldlittle;
if (s < bigend) /* fake up continue to outer loop */
goto top2;
goto check_end;
}
return (char *)s;
}
}
check_end:
if ( s == bigend
&& SvTAIL(littlestr)
&& memEQ((char *)(bigend - littlelen),
(char *)(oldlittle - littlelen), littlelen) )
return (char*)bigend - littlelen;
return NULL;
}
}
char *
Perl_screaminstr(pTHX_ SV *bigstr, SV *littlestr, I32 start_shift, I32 end_shift, I32 *old_posp, I32 last)
{
dVAR;
PERL_ARGS_ASSERT_SCREAMINSTR;
PERL_UNUSED_ARG(bigstr);
PERL_UNUSED_ARG(littlestr);
PERL_UNUSED_ARG(start_shift);
PERL_UNUSED_ARG(end_shift);
PERL_UNUSED_ARG(old_posp);
PERL_UNUSED_ARG(last);
/* This function must only ever be called on a scalar with study magic,
but those do not happen any more. */
Perl_croak(aTHX_ "panic: screaminstr");
return NULL;
}
/*
=for apidoc foldEQ
Returns true if the leading len bytes of the strings s1 and s2 are the same
case-insensitively; false otherwise. Uppercase and lowercase ASCII range bytes
match themselves and their opposite case counterparts. Non-cased and non-ASCII
range bytes match only themselves.
=cut
*/
I32
Perl_foldEQ(const char *s1, const char *s2, I32 len)
{
const U8 *a = (const U8 *)s1;
const U8 *b = (const U8 *)s2;
PERL_ARGS_ASSERT_FOLDEQ;
assert(len >= 0);
while (len--) {
if (*a != *b && *a != PL_fold[*b])
return 0;
a++,b++;
}
return 1;
}
I32
Perl_foldEQ_latin1(const char *s1, const char *s2, I32 len)
{
/* Compare non-utf8 using Unicode (Latin1) semantics. Does not work on
* MICRO_SIGN, LATIN_SMALL_LETTER_SHARP_S, nor
* LATIN_SMALL_LETTER_Y_WITH_DIAERESIS, and does not check for these. Nor
* does it check that the strings each have at least 'len' characters */
const U8 *a = (const U8 *)s1;
const U8 *b = (const U8 *)s2;
PERL_ARGS_ASSERT_FOLDEQ_LATIN1;
assert(len >= 0);
while (len--) {
if (*a != *b && *a != PL_fold_latin1[*b]) {
return 0;
}
a++, b++;
}
return 1;
}
/*
=for apidoc foldEQ_locale
Returns true if the leading len bytes of the strings s1 and s2 are the same
case-insensitively in the current locale; false otherwise.
=cut
*/
I32
Perl_foldEQ_locale(const char *s1, const char *s2, I32 len)
{
dVAR;
const U8 *a = (const U8 *)s1;
const U8 *b = (const U8 *)s2;
PERL_ARGS_ASSERT_FOLDEQ_LOCALE;
assert(len >= 0);
while (len--) {
if (*a != *b && *a != PL_fold_locale[*b])
return 0;
a++,b++;
}
return 1;
}
/* copy a string to a safe spot */
/*
=head1 Memory Management
=for apidoc savepv
Perl's version of C<strdup()>. Returns a pointer to a newly allocated
string which is a duplicate of C<pv>. The size of the string is
determined by C<strlen()>. The memory allocated for the new string can
be freed with the C<Safefree()> function.
=cut
*/
char *
Perl_savepv(pTHX_ const char *pv)
{
PERL_UNUSED_CONTEXT;
if (!pv)
return NULL;
else {
char *newaddr;
const STRLEN pvlen = strlen(pv)+1;
Newx(newaddr, pvlen, char);
return (char*)memcpy(newaddr, pv, pvlen);
}
}
/* same thing but with a known length */
/*
=for apidoc savepvn
Perl's version of what C<strndup()> would be if it existed. Returns a
pointer to a newly allocated string which is a duplicate of the first
C<len> bytes from C<pv>, plus a trailing NUL byte. The memory allocated for
the new string can be freed with the C<Safefree()> function.
=cut
*/
char *
Perl_savepvn(pTHX_ const char *pv, I32 len)
{
char *newaddr;
PERL_UNUSED_CONTEXT;
assert(len >= 0);
Newx(newaddr,len+1,char);
/* Give a meaning to NULL pointer mainly for the use in sv_magic() */
if (pv) {
/* might not be null terminated */
newaddr[len] = '\0';
return (char *) CopyD(pv,newaddr,len,char);
}
else {
return (char *) ZeroD(newaddr,len+1,char);
}
}
/*
=for apidoc savesharedpv
A version of C<savepv()> which allocates the duplicate string in memory
which is shared between threads.
=cut
*/
char *
Perl_savesharedpv(pTHX_ const char *pv)
{
char *newaddr;
STRLEN pvlen;
if (!pv)
return NULL;
pvlen = strlen(pv)+1;
newaddr = (char*)PerlMemShared_malloc(pvlen);
if (!newaddr) {
croak_no_mem();
}
return (char*)memcpy(newaddr, pv, pvlen);
}
/*
=for apidoc savesharedpvn
A version of C<savepvn()> which allocates the duplicate string in memory
which is shared between threads. (With the specific difference that a NULL
pointer is not acceptable)
=cut
*/
char *