char *gconvert(double, int, int, char *);
#endif
+/* void Gconvert: on Linux at least, gcvt (which Gconvert gets deffed to),
+ * has a mandatory return value, even though that value is just the same
+ * as the buf arg */
+
+#define V_Gconvert(x,n,t,b) \
+{ \
+ char *rc = (char *)Gconvert(x,n,t,b); \
+ PERL_UNUSED_VAR(rc); \
+}
+
+
#ifdef PERL_UTF8_CACHE_ASSERT
/* if adding more checks watch out for the following tests:
* t/op/index.t t/op/length.t t/op/pat.t t/op/substr.t
preceding structure in memory.)
We calculate the correction using the STRUCT_OFFSET macro on the first
-member present. If the allocated structure is smaller (no initial NV
+member present. If the allocated structure is smaller (no initial NV
actually allocated) then the net effect is to subtract the size of the NV
from the pointer, to return a new pointer as if an initial NV were actually
-allocated. (We were using structures named *_allocated for this, but
+allocated. (We were using structures named *_allocated for this, but
this turned out to be a subtle bug, because a structure without an NV
could have a lower alignment constraint, but the compiler is allowed to
optimised accesses based on the alignment constraint of the actual pointer
to the full structure, for example, using a single 64 bit load instruction
because it "knows" that two adjacent 32 bit members will be 8-byte aligned.)
-This is the same trick as was used for NV and IV bodies. Ironically it
+This is the same trick as was used for NV and IV bodies. Ironically it
doesn't need to be used for NV bodies any more, because NV is now at
-the start of the structure. IV bodies don't need it either, because
+the start of the structure. IV bodies don't need it either, because
they are no longer allocated.
In turn, the new_body_* allocators call S_new_body(), which invokes
{
dVAR;
- if (!sv)
- return 0;
+ PERL_ARGS_ASSERT_SV_2IV_FLAGS;
assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
&& SvTYPE(sv) != SVt_PVFM);
{
dVAR;
- if (!sv)
- return 0;
+ PERL_ARGS_ASSERT_SV_2UV_FLAGS;
if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
mg_get(sv);
Perl_sv_2nv_flags(pTHX_ SV *const sv, const I32 flags)
{
dVAR;
- if (!sv)
- return 0.0;
+
+ PERL_ARGS_ASSERT_SV_2NV_FLAGS;
+
assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
&& SvTYPE(sv) != SVt_PVFM);
if (SvGMAGICAL(sv) || SvVALID(sv) || isREGEXP(sv)) {
dVAR;
char *s;
- if (!sv) {
- if (lp)
- *lp = 0;
- return (char *)"";
- }
+ PERL_ARGS_ASSERT_SV_2PV_FLAGS;
+
assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
&& SvTYPE(sv) != SVt_PVFM);
if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
/* some Xenix systems wipe out errno here */
#ifndef USE_LOCALE_NUMERIC
- Gconvert(SvNVX(sv), NV_DIG, 0, s);
+ V_Gconvert(SvNVX(sv), NV_DIG, 0, s);
SvPOK_on(sv);
#else
/* Gconvert always uses the current locale. That's the right thing
* But if we're already in the C locale (PL_numeric_standard is
* TRUE in that case), no need to do any changing */
if (PL_numeric_standard || IN_SOME_LOCALE_FORM_RUNTIME) {
- Gconvert(SvNVX(sv), NV_DIG, 0, s);
+ V_Gconvert(SvNVX(sv), NV_DIG, 0, s);
/* If the radix character is UTF-8, and actually is in the
* output, turn on the UTF-8 flag for the scalar */
else {
char *loc = savepv(setlocale(LC_NUMERIC, NULL));
setlocale(LC_NUMERIC, "C");
- Gconvert(SvNVX(sv), NV_DIG, 0, s);
+ V_Gconvert(SvNVX(sv), NV_DIG, 0, s);
setlocale(LC_NUMERIC, loc);
Safefree(loc);
if all the bytes are invariant in UTF-8.
If C<flags> has C<SV_GMAGIC> bit set,
will C<mg_get> on C<sv> if appropriate, else not.
-Returns the number of bytes in the converted string
-C<sv_utf8_upgrade> and
-C<sv_utf8_upgrade_nomg> are implemented in terms of this function.
+
+If C<flags> has SV_FORCE_UTF8_UPGRADE set, this function assumes that the PV
+will expand when converted to UTF-8, and skips the extra work of checking for
+that. Typically this flag is used by a routine that has already parsed the
+string and found such characters, and passes this information on so that the
+work doesn't have to be repeated.
+
+Returns the number of bytes in the converted string.
This is not a general purpose byte encoding to Unicode interface:
use the Encode extension for that.
-=cut
+=for apidoc sv_utf8_upgrade_flags_grow
-The grow version is currently not externally documented. It adds a parameter,
-extra, which is the number of unused bytes the string of 'sv' is guaranteed to
-have free after it upon return. This allows the caller to reserve extra space
-that it intends to fill, to avoid extra grows.
+Like sv_utf8_upgrade_flags, but has an additional parameter C<extra>, which is
+the number of unused bytes the string of 'sv' is guaranteed to have free after
+it upon return. This allows the caller to reserve extra space that it intends
+to fill, to avoid extra grows.
-Also externally undocumented for the moment is the flag SV_FORCE_UTF8_UPGRADE,
-which can be used to tell this function to not first check to see if there are
-any characters that are different in UTF-8 (variant characters) which would
-force it to allocate a new string to sv, but to assume there are. Typically
-this flag is used by a routine that has already parsed the string to find that
-there are such characters, and passes this information on so that the work
-doesn't have to be repeated.
+C<sv_utf8_upgrade>, C<sv_utf8_upgrade_nomg>, and C<sv_utf8_upgrade_flags>
+are implemented in terms of this function.
+
+Returns the number of bytes in the converted string (not including the spares).
+
+=cut
(One might think that the calling routine could pass in the position of the
-first such variant, so it wouldn't have to be found again. But that is not the
-case, because typically when the caller is likely to use this flag, it won't be
-calling this routine unless it finds something that won't fit into a byte.
-Otherwise it tries to not upgrade and just use bytes. But some things that
-do fit into a byte are variants in utf8, and the caller may not have been
-keeping track of these.)
+first variant character when it has set SV_FORCE_UTF8_UPGRADE, so it wouldn't
+have to be found again. But that is not the case, because typically when the
+caller is likely to use this flag, it won't be calling this routine unless it
+finds something that won't fit into a byte. Otherwise it tries to not upgrade
+and just use bytes. But some things that do fit into a byte are variants in
+utf8, and the caller may not have been keeping track of these.)
If the routine itself changes the string, it adds a trailing NUL. Such a NUL
isn't guaranteed due to having other routines do the work in some input cases,
Copies the contents of the source SV C<ssv> into the destination SV
C<dsv>. The source SV may be destroyed if it is mortal, so don't use this
-function if the source SV needs to be reused. Does not handle 'set' magic.
-Loosely speaking, it performs a copy-by-value, obliterating any previous
-content of the destination.
+function if the source SV needs to be reused. Does not handle 'set' magic on
+destination SV. Calls 'get' magic on source SV. Loosely speaking, it
+performs a copy-by-value, obliterating any previous content of the
+destination.
You probably want to use one of the assortment of wrappers, such as
C<SvSetSV>, C<SvSetSV_nosteal>, C<SvSetMagicSV> and
content of the destination.
If the C<flags> parameter has the C<SV_GMAGIC> bit set, will C<mg_get> on
C<ssv> if appropriate, else not. If the C<flags>
-parameter has the C<NOSTEAL> bit set then the
+parameter has the C<SV_NOSTEAL> bit set then the
buffers of temps will not be stolen. <sv_setsv>
and C<sv_setsv_nomg> are implemented in terms of this function.
reg_temp_copy((REGEXP*)dstr, (REGEXP*)sstr);
}
else if (sflags & SVp_POK) {
- bool isSwipe = 0;
const STRLEN cur = SvCUR(sstr);
const STRLEN len = SvLEN(sstr);
/*
- * Check to see if we can just swipe the string. If so, it's a
- * possible small lose on short strings, but a big win on long ones.
- * It might even be a win on short strings if SvPVX_const(dstr)
- * has to be allocated and SvPVX_const(sstr) has to be freed.
- * Likewise if we can set up COW rather than doing an actual copy, we
- * drop to the else clause, as the swipe code and the COW setup code
- * have much in common.
+ * We have three basic ways to copy the string:
+ *
+ * 1. Swipe
+ * 2. Copy-on-write
+ * 3. Actual copy
+ *
+ * Which we choose is based on various factors. The following
+ * things are listed in order of speed, fastest to slowest:
+ * - Swipe
+ * - Copying a short string
+ * - Copy-on-write bookkeeping
+ * - malloc
+ * - Copying a long string
+ *
+ * We swipe the string (steal the string buffer) if the SV on the
+ * rhs is about to be freed anyway (TEMP and refcnt==1). This is a
+ * big win on long strings. It should be a win on short strings if
+ * SvPVX_const(dstr) has to be allocated. If not, it should not
+ * slow things down, as SvPVX_const(sstr) would have been freed
+ * soon anyway.
+ *
+ * We also steal the buffer from a PADTMP (operator target) if it
+ * is ‘long enough’. For short strings, a swipe does not help
+ * here, as it causes more malloc calls the next time the target
+ * is used. Benchmarks show that even if SvPVX_const(dstr) has to
+ * be allocated it is still not worth swiping PADTMPs for short
+ * strings, as the savings here are small.
+ *
+ * If the rhs is already flagged as a copy-on-write string and COW
+ * is possible here, we use copy-on-write and make both SVs share
+ * the string buffer.
+ *
+ * If the rhs is not flagged as copy-on-write, then we see whether
+ * it is worth upgrading it to such. If the lhs already has a buf-
+ * fer big enough and the string is short, we skip it and fall back
+ * to method 3, since memcpy is faster for short strings than the
+ * later bookkeeping overhead that copy-on-write entails.
+ *
+ * If there is no buffer on the left, or the buffer is too small,
+ * then we use copy-on-write.
*/
/* Whichever path we take through the next code, we want this true,
(void)SvPOK_only(dstr);
if (
- /* If we're already COW then this clause is not true, and if COW
- is allowed then we drop down to the else and make dest COW
- with us. If caller hasn't said that we're allowed to COW
- shared hash keys then we don't do the COW setup, even if the
- source scalar is a shared hash key scalar. */
- (((flags & SV_COW_SHARED_HASH_KEYS)
- ? !(sflags & SVf_IsCOW)
-#ifdef PERL_NEW_COPY_ON_WRITE
- || (len &&
- ((!GE_COWBUF_THRESHOLD(cur) && SvLEN(dstr) > cur)
- /* If this is a regular (non-hek) COW, only so many COW
- "copies" are possible. */
- || CowREFCNT(sstr) == SV_COW_REFCNT_MAX))
-#endif
- : 1 /* If making a COW copy is forbidden then the behaviour we
- desire is as if the source SV isn't actually already
- COW, even if it is. So we act as if the source flags
- are not COW, rather than actually testing them. */
- )
-#ifndef PERL_ANY_COW
- /* The change that added SV_COW_SHARED_HASH_KEYS makes the logic
- when PERL_OLD_COPY_ON_WRITE is defined a little wrong.
- Conceptually PERL_OLD_COPY_ON_WRITE being defined should
- override SV_COW_SHARED_HASH_KEYS, because it means "always COW"
- but in turn, it's somewhat dead code, never expected to go
- live, but more kept as a placeholder on how to do it better
- in a newer implementation. */
- /* If we are COW and dstr is a suitable target then we drop down
- into the else and make dest a COW of us. */
- || (SvFLAGS(dstr) & SVf_BREAK)
-#endif
- )
- &&
- !(isSwipe =
-#ifdef PERL_NEW_COPY_ON_WRITE
+ ( /* Either ... */
/* slated for free anyway (and not COW)? */
- (sflags & (SVs_TEMP|SVf_IsCOW)) == SVs_TEMP &&
-#else
- (sflags & SVs_TEMP) && /* slated for free anyway? */
-#endif
+ (sflags & (SVs_TEMP|SVf_IsCOW)) == SVs_TEMP
+ /* or a swipable TARG */
+ || ((sflags & (SVs_PADTMP|SVf_READONLY|SVf_IsCOW))
+ == SVs_PADTMP
+ /* whose buffer is worth stealing */
+ && GE_COWBUF_THRESHOLD(cur)
+ )
+ ) &&
!(sflags & SVf_OOK) && /* and not involved in OOK hack? */
(!(flags & SV_NOSTEAL)) &&
/* and we're allowed to steal temps */
SvREFCNT(sstr) == 1 && /* and no other references to it? */
len) /* and really is a string */
-#ifdef PERL_ANY_COW
- && ((flags & SV_COW_SHARED_HASH_KEYS)
- ? (!((sflags & CAN_COW_MASK) == CAN_COW_FLAGS
-# ifdef PERL_OLD_COPY_ON_WRITE
+ { /* Passes the swipe test. */
+ if (SvPVX_const(dstr)) /* we know that dtype >= SVt_PV */
+ SvPV_free(dstr);
+ SvPV_set(dstr, SvPVX_mutable(sstr));
+ SvLEN_set(dstr, SvLEN(sstr));
+ SvCUR_set(dstr, SvCUR(sstr));
+
+ SvTEMP_off(dstr);
+ (void)SvOK_off(sstr); /* NOTE: nukes most SvFLAGS on sstr */
+ SvPV_set(sstr, NULL);
+ SvLEN_set(sstr, 0);
+ SvCUR_set(sstr, 0);
+ SvTEMP_off(sstr);
+ }
+ else if (flags & SV_COW_SHARED_HASH_KEYS
+ &&
+#ifdef PERL_OLD_COPY_ON_WRITE
+ ( sflags & SVf_IsCOW
+ || ( (sflags & CAN_COW_MASK) == CAN_COW_FLAGS
&& (SvFLAGS(dstr) & CAN_COW_MASK) == CAN_COW_FLAGS
&& SvTYPE(sstr) >= SVt_PVIV && len
-# else
+ )
+ )
+#elif defined(PERL_NEW_COPY_ON_WRITE)
+ (sflags & SVf_IsCOW
+ ? (!len ||
+ ( (GE_COWBUF_THRESHOLD(cur) || SvLEN(dstr) < cur+1)
+ /* If this is a regular (non-hek) COW, only so
+ many COW "copies" are possible. */
+ && CowREFCNT(sstr) != SV_COW_REFCNT_MAX ))
+ : ( (sflags & CAN_COW_MASK) == CAN_COW_FLAGS
&& !(SvFLAGS(dstr) & SVf_BREAK)
- && !(sflags & SVf_IsCOW)
&& GE_COW_THRESHOLD(cur) && cur+1 < len
&& (GE_COWBUF_THRESHOLD(cur) || SvLEN(dstr) < cur+1)
-# endif
))
- : 1)
+#else
+ sflags & SVf_IsCOW
+ && !(SvFLAGS(dstr) & SVf_BREAK)
#endif
) {
- /* Failed the swipe test, and it's not a shared hash key either.
- Have to copy the string. */
- SvGROW(dstr, cur + 1); /* inlined from sv_setpvn */
- Move(SvPVX_const(sstr),SvPVX(dstr),cur,char);
- SvCUR_set(dstr, cur);
- *SvEND(dstr) = '\0';
- } else {
- /* If PERL_OLD_COPY_ON_WRITE is not defined, then isSwipe will always
- be true in here. */
/* Either it's a shared hash key, or it's suitable for
- copy-on-write or we can swipe the string. */
+ copy-on-write. */
if (DEBUG_C_TEST) {
PerlIO_printf(Perl_debug_log, "Copy on write: sstr --> dstr\n");
sv_dump(sstr);
sv_dump(dstr);
}
#ifdef PERL_ANY_COW
- if (!isSwipe) {
- if (!(sflags & SVf_IsCOW)) {
+ if (!(sflags & SVf_IsCOW)) {
SvIsCOW_on(sstr);
# ifdef PERL_OLD_COPY_ON_WRITE
/* Make the source SV into a loop of 1.
# else
CowREFCNT(sstr) = 0;
# endif
- }
}
#endif
- /* Initial code is common. */
if (SvPVX_const(dstr)) { /* we know that dtype >= SVt_PV */
SvPV_free(dstr);
}
- if (!isSwipe) {
- /* making another shared SV. */
#ifdef PERL_ANY_COW
- if (len) {
+ if (len) {
# ifdef PERL_OLD_COPY_ON_WRITE
assert (SvTYPE(dstr) >= SVt_PVIV);
/* SvIsCOW_normal */
CowREFCNT(sstr)++;
# endif
SvPV_set(dstr, SvPVX_mutable(sstr));
- } else
+ } else
#endif
- {
+ {
/* SvIsCOW_shared_hash */
DEBUG_C(PerlIO_printf(Perl_debug_log,
"Copy on write: Sharing hash\n"));
assert (SvTYPE(dstr) >= SVt_PV);
SvPV_set(dstr,
HEK_KEY(share_hek_hek(SvSHARED_HEK_FROM_PV(SvPVX_const(sstr)))));
- }
- SvLEN_set(dstr, len);
- SvCUR_set(dstr, cur);
- SvIsCOW_on(dstr);
- }
- else
- { /* Passes the swipe test. */
- SvPV_set(dstr, SvPVX_mutable(sstr));
- SvLEN_set(dstr, SvLEN(sstr));
- SvCUR_set(dstr, SvCUR(sstr));
-
- SvTEMP_off(dstr);
- (void)SvOK_off(sstr); /* NOTE: nukes most SvFLAGS on sstr */
- SvPV_set(sstr, NULL);
- SvLEN_set(sstr, 0);
- SvCUR_set(sstr, 0);
- SvTEMP_off(sstr);
- }
+ }
+ SvLEN_set(dstr, len);
+ SvCUR_set(dstr, cur);
+ SvIsCOW_on(dstr);
+ } else {
+ /* Failed the swipe test, and we cannot do copy-on-write either.
+ Have to copy the string. */
+ SvGROW(dstr, cur + 1); /* inlined from sv_setpvn */
+ Move(SvPVX_const(sstr),SvPVX(dstr),cur,char);
+ SvCUR_set(dstr, cur);
+ *SvEND(dstr) = '\0';
}
if (sflags & SVp_NOK) {
SvNV_set(dstr, SvNVX(sstr));
=for apidoc sv_gets
Get a line from the filehandle and store it into the SV, optionally
-appending to the currently-stored string. If C<append> is not 0, the
-line is appended to the SV instead of overwriting it. C<append> should
+appending to the currently-stored string.
If C<append> is not 0, the
+line is appended to the SV instead of overwriting it.
C<append> should
be set to the byte offset that the appended string should start at
in the SV (typically, C<SvCUR(sv)> is a suitable choice).
Creates a new SV for the existing RV, C<rv>, to point to. If C<rv> is not an
RV then it will be upgraded to one. If C<classname> is non-null then the new
SV will be blessed in the specified package. The new SV is returned and its
-reference count is 1. The reference count 1 is owned by C<rv>.
+reference count is 1. The reference count 1 is owned by C<rv>.
=cut
*/
a Configure test for this. */
if (digits && digits < sizeof(ebuf) - NV_DIG - 10) {
/* 0, point, slack */
- Gconvert(nv, (int)digits, 0, ebuf);
+ V_Gconvert(nv, (int)digits, 0, ebuf);
sv_catpv_nomg(sv, ebuf);
if (*ebuf) /* May return an empty string for digits==0 */
return;
/* See earlier comment about buggy Gconvert when digits,
aka precis is 0 */
if ( c == 'g' && precis) {
- Gconvert((NV)nv, (int)precis, 0, PL_efloatbuf);
+ V_Gconvert((NV)nv, (int)precis, 0, PL_efloatbuf);
/* May return an empty string for digits==0 */
if (*PL_efloatbuf) {
elen = strlen(PL_efloatbuf);
}
#endif
+ /* hopefully the above makes ptr a very constrained format
+ * that is safe to use, even though it's not literal */
+ GCC_DIAG_IGNORE(-Wformat-nonliteral);
#if defined(HAS_LONG_DOUBLE)
elen = ((intsize == 'q')
? my_snprintf(PL_efloatbuf, PL_efloatsize, ptr, nv)
#else
elen = my_sprintf(PL_efloatbuf, ptr, nv);
#endif
+ GCC_DIAG_RESTORE;
}
float_converted:
eptr = PL_efloatbuf;
DIR *ret;
#ifdef HAS_FCHDIR
+ int rc = 0;
DIR *pwd;
const Direntry_t *dirent;
char smallbuf[256];
/* Now we should have two dir handles pointing to the same dir. */
/* Be nice to the calling code and chdir back to where we were. */
- fchdir(my_dirfd(pwd)); /* If this fails, then what? */
+ rc = fchdir(my_dirfd(pwd));
+ /* XXX If this fails, then what? */
+ PERL_UNUSED_VAR(rc);
/* We have no need of the pwd handle any more. */
PerlDir_close(pwd);
STRLEN len;
const char *s;
dSP;
+ SV *nsv = sv;
ENTER;
+ PUSHSTACK;
SAVETMPS;
+ if (SvPADTMP(nsv)) {
+ nsv = sv_newmortal();
+ SvSetSV_nosteal(nsv, sv);
+ }
save_re_context();
PUSHMARK(sp);
EXTEND(SP, 3);
PUSHs(encoding);
- PUSHs(sv);
+ PUSHs(nsv);
/*
NI-S 2002/07/09
Passing sv_yes is wrong - it needs to be or'ed set of constants
SvCUR_set(sv, len);
}
FREETMPS;
+ POPSTACK;
LEAVE;
if (SvTYPE(sv) >= SVt_PVMG && SvMAGIC(sv)) {
/* clear pos and any utf8 cache */
if (varname)
sv_insert(varname, 0, 0, " ", 1);
}
+ /* PL_warn_uninit_sv is constant */
+ GCC_DIAG_IGNORE(-Wformat-nonliteral);
/* diag_listed_as: Use of uninitialized value%s */
Perl_warner(aTHX_ packWARN(WARN_UNINITIALIZED), PL_warn_uninit_sv,
SVfARG(varname ? varname : &PL_sv_no),
" in ", OP_DESC(PL_op));
+ GCC_DIAG_RESTORE;
}
- else
+ else {
+ /* PL_warn_uninit is constant */
+ GCC_DIAG_IGNORE(-Wformat-nonliteral);
Perl_warner(aTHX_ packWARN(WARN_UNINITIALIZED), PL_warn_uninit,
"", "", "");
+ GCC_DIAG_RESTORE;
+ }
}
/*
https://perl5.git.perl.org / perl5.git / blobdiff