Fix fd leak on Via(bogus).

Finish implementing PerlIOVia_open().
Export more guts of PerlIO_* so Via_open() can work.
Fix various PerlIO_allocate() features exposed by above.

p4raw-id: //depot/perlio@16207

2 files changed, 76 insertions, 5 deletions

diff --git a/ext/PerlIO/Via/Via.xs b/ext/PerlIO/Via/Via.xs
index af5f5ea00f..494ddf9118 100644
--- a/ext/PerlIO/Via/Via.xs
+++ b/ext/PerlIO/Via/Via.xs
@@ -55,6 +55,14 @@ PerlIOVia_fetchmethod(pTHX_ PerlIOVia *s,char *method,CV **save)
   }
 }
 
+/*
+ * Try and call method, possibly via cached lookup.
+ * If method does not exist return Nullsv (caller may fallback to another approach
+ * If method does exist call it with flags passing variable number of args
+ * Last arg is a "filehandle" to layer below (if present)
+ * Returns scalar returned by method (if any) otherwise sv_undef
+ */
+
 SV *
 PerlIOVia_method(pTHX_ PerlIO *f,char *method,CV **save,int flags,...)
 {
@@ -88,6 +96,10 @@ PerlIOVia_method(pTHX_ PerlIO *f,char *method,CV **save,int flags,...)
      IoOFP(s->io) = PerlIONext(f);
      XPUSHs(s->fh);
     }
+   else
+    {
+     PerlIO_debug("No next\n");
+    }
    PUTBACK;
    count = call_sv((SV *)cv,flags);
    if (count)
@@ -117,6 +129,7 @@ PerlIOVia_pushed(pTHX_ PerlIO *f, const char *mode, SV *arg)
     {
      if (ckWARN(WARN_LAYER))
       Perl_warner(aTHX_ packWARN(WARN_LAYER), "No package specified");
+     errno = EINVAL;
      code = -1;
     }
    else
@@ -163,7 +176,9 @@ PerlIOVia_pushed(pTHX_ PerlIO *f, const char *mode, SV *arg)
 }
 
 PerlIO *
-PerlIOVia_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers, IV n, const char *mode, int fd, int imode, int perm, PerlIO *f, int narg, SV **args)
+PerlIOVia_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers, IV n,
+               const char *mode, int fd, int imode, int perm,
+               PerlIO *f, int narg, SV **args)
 {
  if (!f)
   {
@@ -171,6 +186,7 @@ PerlIOVia_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers, IV n, const char
   }
  else
   {
+   /* Reopen */
    if (!PerlIO_push(aTHX_ f,self,mode,PerlIOArg))
     return NULL;
   }
@@ -206,7 +222,44 @@ PerlIOVia_open(pTHX_ PerlIO_funcs *self, PerlIO_list_t *layers, IV n, const char
       }
     }
    else
-    return NULL;
+    {
+	/* Required open method not present */
+	PerlIO_funcs *tab = NULL;
+	IV m = n-1;
+	while (m >= 0) {
+	    PerlIO_funcs *t = PerlIO_layer_fetch(aTHX_ layers, m, NULL);
+	    if (t && t->Open) {
+		tab = t;
+		break;
+	    }
+	    n--;
+	}
+	if (tab) {
+	    if ((*tab->Open) (aTHX_ tab, layers, m, mode, fd, imode, perm,
+			      PerlIONext(f), narg, args)) {
+		PerlIO_debug("Opened with %s => %p->%p\n",tab->name,PerlIONext(f),*PerlIONext(f));
+		if (m + 1 < n) {
+		    /*
+		     * More layers above the one that we used to open -
+		     * apply them now
+		     */
+		    if (PerlIO_apply_layera(aTHX_ PerlIONext(f), mode, layers, m+1, n) != 0) {
+			/* If pushing layers fails close the file */
+			PerlIO_close(f);
+			f = NULL;
+		    }
+		}
+		return f;
+	    }
+	    else {
+		/* Sub-layer open failed */
+	    }
+	}
+	else {
+	    /* Nothing to do the open */
+	}
+     return NULL;
+    }
   }
  return f;
 }
@@ -494,7 +547,7 @@ PerlIO_funcs PerlIO_object = {
  PERLIO_K_BUFFERED|PERLIO_K_DESTRUCT,
  PerlIOVia_pushed,
  PerlIOVia_popped,
- NULL, /* PerlIOVia_open, */
+ PerlIOVia_open, /* NULL, */
  PerlIOVia_getarg,
  PerlIOVia_fileno,
  PerlIOVia_dup,
diff --git a/ext/PerlIO/t/via.t b/ext/PerlIO/t/via.t
index 89a1e13236..43ea3c5a95 100644
--- a/ext/PerlIO/t/via.t
+++ b/ext/PerlIO/t/via.t
@@ -14,7 +14,7 @@ BEGIN {
 
 my $tmp = "via$$";
 
-use Test::More tests => 11;
+use Test::More tests => 13;
 
 my $fh;
 my $a = join("", map { chr } 0..255) x 10;
@@ -38,14 +38,32 @@ is($a, $b, 'compare original data with filtered version');
     local $SIG{__WARN__} = sub { $warnings = join '', @_ };
 
     use warnings 'layer';
+
+    # Find fd number we should be using
+    my $fd = open($fh,">$tmp") && fileno($fh);
+    print $fh "Hello\n";
+    close($fh);
+
     ok( ! open($fh,">Via(Unknown::Module)", $tmp), 'open Via Unknown::Module will fail');
     like( $warnings, qr/^Cannot find package 'Unknown::Module'/,  'warn about unknown package' );
 
+    # Now open normally again to see if we get right fileno
+    my $fd2 = open($fh,"<$tmp") && fileno($fh);
+    is($fd2,$fd,"Wrong fd number after failed open");
+
+    my $data = <$fh>;
+
+    is($data,"Hello\n","File clobbered by failed open");
+
+    close($fh);
+
+
+
     $warnings = '';
     no warnings 'layer';
     ok( ! open($fh,">Via(Unknown::Module)", $tmp), 'open Via Unknown::Module will fail');
     is( $warnings, "",  "don't warn about unknown package" );
-}    
+}
 
 END {
     1 while unlink $tmp;