X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=perlio.c;h=304d106ecb7ef9a979fec7a4625dc73a1057895e;hb=9f2f055aa1e8c86d97b5ea42473ab1747f518f3a;hp=b7f2b14be7296a82c9ae0ddfdb0f1a7d81afb63f;hpb=7918f24d20384771923d344a382e1d16d9552018;p=p5sagit%2Fp5-mst-13.2.git diff --git a/perlio.c b/perlio.c index b7f2b14..304d106 100644 --- a/perlio.c +++ b/perlio.c @@ -1,7 +1,7 @@ /* * perlio.c * Copyright (c) 1996-2006, Nick Ing-Simmons - * Copyright (c) 2006, 2007, Larry Wall and others + * Copyright (c) 2006, 2007, 2008 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. @@ -10,6 +10,8 @@ /* * Hour after hour for nearly three weary days he had jogged up and down, * over passes, and through long dales, and across many streams. + * + * [pp.791-792 of _The Lord of the Rings_, V/iii: "The Muster of Rohan"] */ /* This file contains the functions needed to implement PerlIO, which @@ -810,7 +812,7 @@ PerlIO_find_layer(pTHX_ const char *name, STRLEN len, int load) SAVEINT(PL_in_load_module); if (cv) { SAVEGENERICSV(PL_warnhook); - PL_warnhook = (SV *) (SvREFCNT_inc_simple_NN(cv)); + PL_warnhook = MUTABLE_SV((SvREFCNT_inc_simple_NN(cv))); } PL_in_load_module++; /* @@ -832,7 +834,7 @@ static int perlio_mg_set(pTHX_ SV *sv, MAGIC *mg) { if (SvROK(sv)) { - IO * const io = GvIOn((GV *) SvRV(sv)); + IO * const io = GvIOn(MUTABLE_GV(SvRV(sv))); PerlIO * const ifp = IoIFP(io); PerlIO * const ofp = IoOFP(io); Perl_warn(aTHX_ "set %" SVf " %p %p %p", @@ -845,7 +847,7 @@ static int perlio_mg_get(pTHX_ SV *sv, MAGIC *mg) { if (SvROK(sv)) { - IO * const io = GvIOn((GV *) SvRV(sv)); + IO * const io = GvIOn(MUTABLE_GV(SvRV(sv))); PerlIO * const ifp = IoIFP(io); PerlIO * const ofp = IoOFP(io); Perl_warn(aTHX_ "get %" SVf " %p %p %p", @@ -884,7 +886,7 @@ XS(XS_io_MODIFY_SCALAR_ATTRIBUTES) MAGIC *mg; int count = 0; int i; - sv_magic(sv, (SV *) av, PERL_MAGIC_ext, NULL, 0); + sv_magic(sv, MUTABLE_SV(av), PERL_MAGIC_ext, NULL, 0); SvRMAGICAL_off(sv); mg = mg_find(sv, PERL_MAGIC_ext); mg->mg_virtual = &perlio_vtab; @@ -1295,7 +1297,7 @@ PerlIORaw_pushed(pTHX_ PerlIO *f, const char *mode, SV *arg, PerlIO_funcs *tab) while (t && (l = *t)) { if (l->tab->Binmode) { /* Has a handler - normal case */ - if ((*l->tab->Binmode)(aTHX_ f) == 0) { + if ((*l->tab->Binmode)(aTHX_ t) == 0) { if (*t == l) { /* Layer still there - move down a layer */ t = PerlIONext(t); @@ -2424,7 +2426,7 @@ PerlIO_cleanup(pTHX) } } -void PerlIO_teardown() /* Call only from PERL_SYS_TERM(). */ +void PerlIO_teardown(void) /* Call only from PERL_SYS_TERM(). */ { dVAR; #if 0 @@ -3130,7 +3132,10 @@ PerlIOStdio_close(pTHX_ PerlIO *f) int invalidate = 0; IV result = 0; int saveerr = 0; - int dupfd = 0; + int dupfd = -1; +#ifdef USE_ITHREADS + dVAR; +#endif #ifdef SOCKS5_VERSION_NAME /* Socks lib overrides close() but stdio isn't linked to that library (though we are) - so we must call close() @@ -3141,8 +3146,15 @@ PerlIOStdio_close(pTHX_ PerlIO *f) if (getsockopt(fd, SOL_SOCKET, SO_TYPE, (void *) &optval, &optlen) == 0) invalidate = 1; #endif - if (PerlIOUnix_refcnt_dec(fd) > 0) /* File descriptor still in use */ + /* Test for -1, as *BSD stdio (at least) on fclose sets the FILE* such + that a subsequent fileno() on it returns -1. Don't want to croak() + from within PerlIOUnix_refcnt_dec() if some buggy caller code is + trying to close an already closed handle which somehow it still has + a reference to. (via.xs, I'm looking at you). */ + if (fd != -1 && PerlIOUnix_refcnt_dec(fd) > 0) { + /* File descriptor still in use */ invalidate = 1; + } if (invalidate) { /* For STD* handles, don't close stdio, since we shared the FILE *, too. */ if (stdio == stdin) /* Some stdios are buggy fflush-ing inputs */ @@ -3156,8 +3168,37 @@ PerlIOStdio_close(pTHX_ PerlIO *f) result = PerlIO_flush(f); saveerr = errno; invalidate = PerlIOStdio_invalidate_fileno(aTHX_ stdio); - if (!invalidate) + if (!invalidate) { +#ifdef USE_ITHREADS + MUTEX_LOCK(&PL_perlio_mutex); + /* Right. We need a mutex here because for a brief while we + will have the situation that fd is actually closed. Hence if + a second thread were to get into this block, its dup() would + likely return our fd as its dupfd. (after all, it is closed) + Then if we get to the dup2() first, we blat the fd back + (messing up its temporary as a side effect) only for it to + then close its dupfd (== our fd) in its close(dupfd) */ + + /* There is, of course, a race condition, that any other thread + trying to input/output/whatever on this fd will be stuffed + for the duration of this little manoeuvrer. Perhaps we + should hold an IO mutex for the duration of every IO + operation if we know that invalidate doesn't work on this + platform, but that would suck, and could kill performance. + + Except that correctness trumps speed. + Advice from klortho #11912. */ +#endif dupfd = PerlLIO_dup(fd); +#ifdef USE_ITHREADS + if (dupfd < 0) { + MUTEX_UNLOCK(&PL_perlio_mutex); + /* Oh cXap. This isn't going to go well. Not sure if we can + recover from here, or if closing this particular FILE * + is a good idea now. */ + } +#endif + } } result = PerlSIO_fclose(stdio); /* We treat error from stdio as success if we invalidated @@ -3171,9 +3212,12 @@ PerlIOStdio_close(pTHX_ PerlIO *f) /* in SOCKS' case, let close() determine return value */ result = close(fd); #endif - if (dupfd) { + if (dupfd >= 0) { PerlLIO_dup2(dupfd,fd); PerlLIO_close(dupfd); +#ifdef USE_ITHREADS + MUTEX_UNLOCK(&PL_perlio_mutex); +#endif } return result; } @@ -4103,6 +4147,9 @@ void PerlIOBuf_set_ptrcnt(pTHX_ PerlIO *f, STDCHAR * ptr, SSize_t cnt) { PerlIOBuf * const b = PerlIOSelf(f, PerlIOBuf); +#ifndef DEBUGGING + PERL_UNUSED_ARG(cnt); +#endif if (!b->buf) PerlIO_get_base(f); b->ptr = ptr;