/*
* proto.h
*
- * Copyright (c) 1997-2002, Larry Wall
+ * Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999,
+ * 2000, 2001, 2002, 2003, 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.
PERL_CALLCONV void perl_free(PerlInterpreter* interp);
PERL_CALLCONV int perl_run(PerlInterpreter* interp);
PERL_CALLCONV int perl_parse(PerlInterpreter* interp, XSINIT_t xsinit, int argc, char** argv, char** env);
+PERL_CALLCONV bool Perl_doing_taint(int argc, char** argv, char** env);
#if defined(USE_ITHREADS)
PERL_CALLCONV PerlInterpreter* perl_clone(PerlInterpreter* interp, UV flags);
# if defined(PERL_IMPLICIT_SYS)
#endif
PERL_CALLCONV OP* Perl_convert(pTHX_ I32 optype, I32 flags, OP* o);
PERL_CALLCONV void Perl_croak(pTHX_ const char* pat, ...) __attribute__((noreturn))
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_1,pTHX_2)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_1,pTHX_2);
PERL_CALLCONV void Perl_vcroak(pTHX_ const char* pat, va_list* args) __attribute__((noreturn));
#if defined(PERL_IMPLICIT_CONTEXT)
PERL_CALLCONV void Perl_croak_nocontext(const char* pat, ...) __attribute__((noreturn))
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
PERL_CALLCONV OP* Perl_die_nocontext(const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
PERL_CALLCONV void Perl_deb_nocontext(const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
PERL_CALLCONV char* Perl_form_nocontext(const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
PERL_CALLCONV void Perl_load_module_nocontext(U32 flags, SV* name, SV* ver, ...);
PERL_CALLCONV SV* Perl_mess_nocontext(const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
PERL_CALLCONV void Perl_warn_nocontext(const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
PERL_CALLCONV void Perl_warner_nocontext(U32 err, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,2,3)))
-#endif
-;
+ __attribute__format__(__printf__,2,3);
PERL_CALLCONV SV* Perl_newSVpvf_nocontext(const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
PERL_CALLCONV void Perl_sv_catpvf_nocontext(SV* sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,2,3)))
-#endif
-;
+ __attribute__format__(__printf__,2,3);
PERL_CALLCONV void Perl_sv_setpvf_nocontext(SV* sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,2,3)))
-#endif
-;
+ __attribute__format__(__printf__,2,3);
PERL_CALLCONV void Perl_sv_catpvf_mg_nocontext(SV* sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,2,3)))
-#endif
-;
+ __attribute__format__(__printf__,2,3);
PERL_CALLCONV void Perl_sv_setpvf_mg_nocontext(SV* sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,2,3)))
-#endif
-;
+ __attribute__format__(__printf__,2,3);
PERL_CALLCONV int Perl_fprintf_nocontext(PerlIO* stream, const char* fmt, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,2,3)))
-#endif
-;
+ __attribute__format__(__printf__,2,3);
PERL_CALLCONV int Perl_printf_nocontext(const char* fmt, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,1,2)))
-#endif
-;
+ __attribute__format__(__printf__,1,2);
#endif
PERL_CALLCONV void Perl_cv_ckproto(pTHX_ CV* cv, GV* gv, char* p);
PERL_CALLCONV CV* Perl_cv_clone(pTHX_ CV* proto);
PERL_CALLCONV PPADDR_t* Perl_get_ppaddr(pTHX);
PERL_CALLCONV I32 Perl_cxinc(pTHX);
PERL_CALLCONV void Perl_deb(pTHX_ const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_1,pTHX_2)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_1,pTHX_2);
PERL_CALLCONV void Perl_vdeb(pTHX_ const char* pat, va_list* args);
PERL_CALLCONV void Perl_debprofdump(pTHX);
PERL_CALLCONV I32 Perl_debop(pTHX_ OP* o);
PERL_CALLCONV void Perl_deprecate(pTHX_ char* s);
PERL_CALLCONV void Perl_deprecate_old(pTHX_ char* s);
PERL_CALLCONV OP* Perl_die(pTHX_ const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_1,pTHX_2)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_1,pTHX_2);
PERL_CALLCONV OP* Perl_vdie(pTHX_ const char* pat, va_list* args);
PERL_CALLCONV OP* Perl_die_where(pTHX_ char* message, STRLEN msglen);
PERL_CALLCONV void Perl_dounwind(pTHX_ I32 cxix);
PERL_CALLCONV OP* Perl_force_list(pTHX_ OP* arg);
PERL_CALLCONV OP* Perl_fold_constants(pTHX_ OP* arg);
PERL_CALLCONV char* Perl_form(pTHX_ const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_1,pTHX_2)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_1,pTHX_2);
PERL_CALLCONV char* Perl_vform(pTHX_ const char* pat, va_list* args);
PERL_CALLCONV void Perl_free_tmps(pTHX);
PERL_CALLCONV OP* Perl_gen_constant_list(pTHX_ OP* o);
PERL_CALLCONV int Perl_magic_setnkeys(pTHX_ SV* sv, MAGIC* mg);
PERL_CALLCONV int Perl_magic_setpack(pTHX_ SV* sv, MAGIC* mg);
PERL_CALLCONV int Perl_magic_setpos(pTHX_ SV* sv, MAGIC* mg);
+PERL_CALLCONV int Perl_magic_setregexp(pTHX_ SV* sv, MAGIC* mg);
PERL_CALLCONV int Perl_magic_setsig(pTHX_ SV* sv, MAGIC* mg);
PERL_CALLCONV int Perl_magic_setsubstr(pTHX_ SV* sv, MAGIC* mg);
PERL_CALLCONV int Perl_magic_settaint(pTHX_ SV* sv, MAGIC* mg);
PERL_CALLCONV char* Perl_mem_collxfrm(pTHX_ const char* s, STRLEN len, STRLEN* xlen);
#endif
PERL_CALLCONV SV* Perl_mess(pTHX_ const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_1,pTHX_2)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_1,pTHX_2);
PERL_CALLCONV SV* Perl_vmess(pTHX_ const char* pat, va_list* args);
PERL_CALLCONV void Perl_qerror(pTHX_ SV* err);
PERL_CALLCONV void Perl_sortsv(pTHX_ SV ** array, size_t num_elts, SVCOMPARE_t cmp);
PERL_CALLCONV SV* Perl_newSVpvn(pTHX_ const char* s, STRLEN len);
PERL_CALLCONV SV* Perl_newSVpvn_share(pTHX_ const char* s, I32 len, U32 hash);
PERL_CALLCONV SV* Perl_newSVpvf(pTHX_ const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_1,pTHX_2)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_1,pTHX_2);
PERL_CALLCONV SV* Perl_vnewSVpvf(pTHX_ const char* pat, va_list* args);
PERL_CALLCONV SV* Perl_newSVrv(pTHX_ SV* rv, const char* classname);
PERL_CALLCONV SV* Perl_newSVsv(pTHX_ SV* old);
PERL_CALLCONV void Perl_set_numeric_standard(pTHX);
PERL_CALLCONV void Perl_require_pv(pTHX_ const char* pv);
PERL_CALLCONV void Perl_pack_cat(pTHX_ SV *cat, char *pat, char *patend, SV **beglist, SV **endlist, SV ***next_in_list, U32 flags);
+PERL_CALLCONV void Perl_packlist(pTHX_ SV *cat, char *pat, char *patend, SV **beglist, SV **endlist);
PERL_CALLCONV void Perl_pidgone(pTHX_ Pid_t pid, int status);
PERL_CALLCONV void Perl_pmflag(pTHX_ U32* pmfl, int ch);
PERL_CALLCONV OP* Perl_pmruntime(pTHX_ OP* pm, OP* expr, OP* repl);
PERL_CALLCONV char* Perl_savesharedpv(pTHX_ const char* pv);
PERL_CALLCONV char* Perl_savepvn(pTHX_ const char* pv, I32 len);
PERL_CALLCONV void Perl_savestack_grow(pTHX);
+PERL_CALLCONV void Perl_savestack_grow_cnt(pTHX_ I32 need);
PERL_CALLCONV void Perl_save_aelem(pTHX_ AV* av, I32 idx, SV **sptr);
PERL_CALLCONV I32 Perl_save_alloc(pTHX_ I32 size, I32 pad);
PERL_CALLCONV void Perl_save_aptr(pTHX_ AV** aptr);
PERL_CALLCONV int Perl_sv_backoff(pTHX_ SV* sv);
PERL_CALLCONV SV* Perl_sv_bless(pTHX_ SV* sv, HV* stash);
PERL_CALLCONV void Perl_sv_catpvf(pTHX_ SV* sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_2,pTHX_3)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_2,pTHX_3);
PERL_CALLCONV void Perl_sv_vcatpvf(pTHX_ SV* sv, const char* pat, va_list* args);
PERL_CALLCONV void Perl_sv_catpv(pTHX_ SV* sv, const char* ptr);
/* PERL_CALLCONV void sv_catpvn(pTHX_ SV* sv, const char* ptr, STRLEN len); */
PERL_CALLCONV bool Perl_sv_derived_from(pTHX_ SV* sv, const char* name);
PERL_CALLCONV I32 Perl_sv_eq(pTHX_ SV* sv1, SV* sv2);
PERL_CALLCONV void Perl_sv_free(pTHX_ SV* sv);
+PERL_CALLCONV void Perl_sv_free2(pTHX_ SV* sv);
PERL_CALLCONV void Perl_sv_free_arenas(pTHX);
PERL_CALLCONV char* Perl_sv_gets(pTHX_ SV* sv, PerlIO* fp, I32 append);
PERL_CALLCONV char* Perl_sv_grow(pTHX_ SV* sv, STRLEN newlen);
PERL_CALLCONV char* Perl_sv_pvutf8n_force(pTHX_ SV* sv, STRLEN* lp);
PERL_CALLCONV char* Perl_sv_pvbyten_force(pTHX_ SV* sv, STRLEN* lp);
PERL_CALLCONV char* Perl_sv_recode_to_utf8(pTHX_ SV* sv, SV *encoding);
+PERL_CALLCONV bool Perl_sv_cat_decode(pTHX_ SV* dsv, SV *encoding, SV *ssv, int *offset, char* tstr, int tlen);
PERL_CALLCONV char* Perl_sv_reftype(pTHX_ SV* sv, int ob);
PERL_CALLCONV void Perl_sv_replace(pTHX_ SV* sv, SV* nsv);
PERL_CALLCONV void Perl_sv_report_used(pTHX);
PERL_CALLCONV void Perl_sv_reset(pTHX_ char* s, HV* stash);
PERL_CALLCONV void Perl_sv_setpvf(pTHX_ SV* sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_2,pTHX_3)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_2,pTHX_3);
PERL_CALLCONV void Perl_sv_vsetpvf(pTHX_ SV* sv, const char* pat, va_list* args);
PERL_CALLCONV void Perl_sv_setiv(pTHX_ SV* sv, IV num);
+PERL_CALLCONV void Perl_sv_setpviv(pTHX_ SV* sv, IV num);
PERL_CALLCONV void Perl_sv_setuv(pTHX_ SV* sv, UV num);
PERL_CALLCONV void Perl_sv_setnv(pTHX_ SV* sv, NV num);
PERL_CALLCONV SV* Perl_sv_setref_iv(pTHX_ SV* rv, const char* classname, IV iv);
PERL_CALLCONV I32 Perl_unlnk(pTHX_ char* f);
#endif
PERL_CALLCONV I32 Perl_unpack_str(pTHX_ char *pat, char *patend, char *s, char *strbeg, char *strend, char **new_s, I32 ocnt, U32 flags);
+PERL_CALLCONV I32 Perl_unpackstring(pTHX_ char *pat, char *patend, char *s, char *strend, U32 flags);
PERL_CALLCONV void Perl_unsharepvn(pTHX_ const char* sv, I32 len, U32 hash);
PERL_CALLCONV void Perl_unshare_hek(pTHX_ HEK* hek);
-PERL_CALLCONV void Perl_utilize(pTHX_ int aver, I32 floor, OP* version, OP* id, OP* arg);
+PERL_CALLCONV void Perl_utilize(pTHX_ int aver, I32 floor, OP* version, OP* idop, OP* arg);
PERL_CALLCONV U8* Perl_utf16_to_utf8(pTHX_ U8* p, U8 *d, I32 bytelen, I32 *newlen);
PERL_CALLCONV U8* Perl_utf16_to_utf8_reversed(pTHX_ U8* p, U8 *d, I32 bytelen, I32 *newlen);
PERL_CALLCONV STRLEN Perl_utf8_length(pTHX_ U8* s, U8 *e);
PERL_CALLCONV void Perl_vivify_defelem(pTHX_ SV* sv);
PERL_CALLCONV void Perl_vivify_ref(pTHX_ SV* sv, U32 to_what);
PERL_CALLCONV I32 Perl_wait4pid(pTHX_ Pid_t pid, int* statusp, int flags);
+PERL_CALLCONV U32 Perl_parse_unicode_opts(pTHX_ char **popt);
+PERL_CALLCONV U32 Perl_seed(pTHX);
PERL_CALLCONV void Perl_report_evil_fh(pTHX_ GV *gv, IO *io, I32 op);
PERL_CALLCONV void Perl_report_uninit(pTHX);
PERL_CALLCONV void Perl_warn(pTHX_ const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_1,pTHX_2)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_1,pTHX_2);
PERL_CALLCONV void Perl_vwarn(pTHX_ const char* pat, va_list* args);
PERL_CALLCONV void Perl_warner(pTHX_ U32 err, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_2,pTHX_3)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_2,pTHX_3);
PERL_CALLCONV void Perl_vwarner(pTHX_ U32 err, const char* pat, va_list* args);
PERL_CALLCONV void Perl_watch(pTHX_ char** addr);
PERL_CALLCONV I32 Perl_whichsig(pTHX_ char* sig);
+PERL_CALLCONV void Perl_write_to_stderr(pTHX_ const char* message, int msglen);
PERL_CALLCONV int Perl_yyerror(pTHX_ char* s);
#ifdef USE_PURE_BISON
PERL_CALLCONV int Perl_yylex_r(pTHX_ YYSTYPE *lvalp, int *lcharp);
PERL_CALLCONV int Perl_runops_standard(pTHX);
PERL_CALLCONV int Perl_runops_debug(pTHX);
PERL_CALLCONV void Perl_sv_catpvf_mg(pTHX_ SV *sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_2,pTHX_3)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_2,pTHX_3);
PERL_CALLCONV void Perl_sv_vcatpvf_mg(pTHX_ SV* sv, const char* pat, va_list* args);
PERL_CALLCONV void Perl_sv_catpv_mg(pTHX_ SV *sv, const char *ptr);
PERL_CALLCONV void Perl_sv_catpvn_mg(pTHX_ SV *sv, const char *ptr, STRLEN len);
PERL_CALLCONV void Perl_sv_catsv_mg(pTHX_ SV *dstr, SV *sstr);
PERL_CALLCONV void Perl_sv_setpvf_mg(pTHX_ SV *sv, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_2,pTHX_3)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_2,pTHX_3);
PERL_CALLCONV void Perl_sv_vsetpvf_mg(pTHX_ SV* sv, const char* pat, va_list* args);
PERL_CALLCONV void Perl_sv_setiv_mg(pTHX_ SV *sv, IV i);
+PERL_CALLCONV void Perl_sv_setpviv_mg(pTHX_ SV *sv, IV iv);
PERL_CALLCONV void Perl_sv_setuv_mg(pTHX_ SV *sv, UV u);
PERL_CALLCONV void Perl_sv_setnv_mg(pTHX_ SV *sv, NV num);
PERL_CALLCONV void Perl_sv_setpv_mg(pTHX_ SV *sv, const char *ptr);
PERL_CALLCONV MGVTBL* Perl_get_vtbl(pTHX_ int vtbl_id);
PERL_CALLCONV char* Perl_pv_display(pTHX_ SV *dsv, char *pv, STRLEN cur, STRLEN len, STRLEN pvlim);
PERL_CALLCONV void Perl_dump_indent(pTHX_ I32 level, PerlIO *file, const char* pat, ...)
-#ifdef CHECK_FORMAT
- __attribute__((format(printf,pTHX_3,pTHX_4)))
-#endif
-;
+ __attribute__format__(__printf__,pTHX_3,pTHX_4);
PERL_CALLCONV void Perl_dump_vindent(pTHX_ I32 level, PerlIO *file, const char* pat, va_list *args);
PERL_CALLCONV void Perl_do_gv_dump(pTHX_ I32 level, PerlIO *file, char *name, GV *sv);
PERL_CALLCONV void Perl_do_gvgv_dump(pTHX_ I32 level, PerlIO *file, char *name, GV *sv);
#if defined(PERL_IN_PP_C) || defined(PERL_DECL_PROT)
STATIC SV* S_refto(pTHX_ SV* sv);
-STATIC U32 S_seed(pTHX);
#endif
#if defined(PERL_IN_PP_PACK_C) || defined(PERL_DECL_PROT)
-STATIC void S_doencodes(pTHX_ SV* sv, char* s, I32 len);
+STATIC I32 S_unpack_rec(pTHX_ tempsym_t* symptr, char *s, char *strbeg, char *strend, char **new_s);
+STATIC SV ** S_pack_rec(pTHX_ SV *cat, tempsym_t* symptr, SV **beglist, SV **endlist);
STATIC SV* S_mul128(pTHX_ SV *sv, U8 m);
+STATIC I32 S_measure_struct(pTHX_ tempsym_t* symptr);
+STATIC char * S_group_end(pTHX_ char *pat, char *patend, char ender);
+STATIC char * S_get_num(pTHX_ char *ppat, I32 *);
+STATIC bool S_next_symbol(pTHX_ tempsym_t* symptr);
+STATIC void S_doencodes(pTHX_ SV* sv, char* s, I32 len);
STATIC SV* S_is_an_int(pTHX_ char *s, STRLEN l);
STATIC int S_div128(pTHX_ SV *pnum, bool *done);
-STATIC char * S_next_symbol(pTHX_ char *pat, char *patend);
-STATIC I32 S_find_count(pTHX_ char **ppat, char *patend, int *star);
-STATIC char * S_group_end(pTHX_ char *pat, char *patend, char ender);
-STATIC I32 S_measure_struct(pTHX_ char *pat, char *patend);
#endif
#if defined(PERL_IN_PP_CTL_C) || defined(PERL_DECL_PROT)
STATIC I32 S_dopoptosub_at(pTHX_ PERL_CONTEXT* cxstk, I32 startingblock);
STATIC void S_save_lines(pTHX_ AV *array, SV *sv);
STATIC OP* S_doeval(pTHX_ int gimme, OP** startop, CV* outside, U32 seq);
-STATIC PerlIO * S_doopen_pmc(pTHX_ const char *name, const char *mode);
+STATIC PerlIO * S_doopen_pm(pTHX_ const char *name, const char *mode);
STATIC bool S_path_is_absolute(pTHX_ char *name);
#endif
STATIC SV* S_mess_alloc(pTHX);
#endif
+#if defined(PERL_IN_NUMERIC_C) || defined(PERL_DECL_PROT)
+STATIC NV S_mulexp10(NV value, I32 exponent);
+#endif
+
START_EXTERN_C
PERL_CALLCONV void Perl_sv_setsv_flags(pTHX_ SV* dsv, SV* ssv, I32 flags);
PERL_CALLCONV void Perl_sv_copypv(pTHX_ SV* dsv, SV* ssv);
PERL_CALLCONV char* Perl_my_atof2(pTHX_ const char *s, NV* value);
PERL_CALLCONV int Perl_my_socketpair(int family, int type, int protocol, int fd[2]);
+#ifdef PERL_COPY_ON_WRITE
+PERL_CALLCONV SV* Perl_sv_setsv_cow(pTHX_ SV* dsv, SV* ssv);
+#endif
#if defined(USE_PERLIO) && !defined(USE_SFIO)
PERL_CALLCONV int Perl_PerlIO_close(pTHX_ PerlIO *);
PERL_CALLCONV void Perl_pad_push(pTHX_ PADLIST *padlist, int depth, int has_args);
#if defined(PERL_IN_PAD_C) || defined(PERL_DECL_PROT)
-STATIC PADOFFSET S_pad_findlex(pTHX_ char* name, PADOFFSET newoff, CV* innercv);
+STATIC PADOFFSET S_pad_findlex(pTHX_ char *name, CV* cv, U32 seq, int warn, SV** out_capture, SV** out_name_sv, int *out_flags);
# if defined(DEBUGGING)
STATIC void S_cv_dump(pTHX_ CV *cv, char *title);
# endif
-STATIC CV* S_cv_clone2(pTHX_ CV *proto, CV *outside);
#endif
PERL_CALLCONV CV* Perl_find_runcv(pTHX_ U32 *db_seqp);
+PERL_CALLCONV void Perl_free_tied_hv_pool(pTHX);
+#if defined(DEBUGGING)
+PERL_CALLCONV int Perl_get_debug_opts(pTHX_ char **s);
+#endif