Special case :stdio pushed method so that "-|:stdio" does

not have an uninitialized layer on top.

p4raw-id: //depot/perlio@17433

diff --git a/perlio.c b/perlio.c
index b4b23d4..925920d 100644 (file)
--- a/perlio.c
+++ b/perlio.c
@@ -2307,8 +2307,10 @@ SSize_t
 PerlIOUnix_read(pTHX_ PerlIO *f, void *vbuf, Size_t count)
 {
     int fd = PerlIOSelf(f, PerlIOUnix)->fd;
-    if (!(PerlIOBase(f)->flags & PERLIO_F_CANREAD))
+    if (!(PerlIOBase(f)->flags & PERLIO_F_CANREAD) || 
+         PerlIOBase(f)->flags & (PERLIO_F_EOF|PERLIO_F_ERROR)) {
        return 0;
+    }
     while (1) {
        SSize_t len = PerlLIO_read(fd, vbuf, count);
        if (len >= 0 || errno != EINTR) {
@@ -2455,25 +2457,30 @@ PerlIOStdio_mode(const char *mode, char *tmode)
     return ret;
 }
 
-/*
- * This isn't used yet ...
- */
 IV
 PerlIOStdio_pushed(pTHX_ PerlIO *f, const char *mode, SV *arg, PerlIO_funcs *tab)
 {
-    if (*PerlIONext(f)) {
-       PerlIOStdio *s = PerlIOSelf(f, PerlIOStdio);
-       char tmode[8];
-       FILE *stdio =
-           PerlSIO_fdopen(PerlIO_fileno(PerlIONext(f)), mode =
-                          PerlIOStdio_mode(mode, tmode));
-       if (stdio) {
-           s->stdio = stdio;
-           /* We never call down so do any pending stuff now */
-           PerlIO_flush(PerlIONext(f));
-       }
-       else
-           return -1;
+    PerlIO *n;
+    if (PerlIOValid(f) && PerlIOValid(n = PerlIONext(f))) {
+        PerlIO_funcs *toptab = PerlIOBase(n)->tab;
+        if (toptab == tab) {
+           /* Top is already stdio - pop self (duplicate) and use original */
+           PerlIO_pop(aTHX_ f);
+           return 0;
+       } else {
+           int fd = PerlIO_fileno(n);
+           char tmode[8];
+           FILE *stdio;
+           if (fd >= 0 && (stdio  = PerlSIO_fdopen(fd, 
+                           mode = PerlIOStdio_mode(mode, tmode)))) {
+               PerlIOSelf(f, PerlIOStdio)->stdio = stdio;
+               /* We never call down so do any pending stuff now */
+               PerlIO_flush(PerlIONext(f));
+           } 
+           else {
+               return -1;
+           }
+        }
     }
     return PerlIOBase_pushed(aTHX_ f, mode, arg, tab);
 }
@@ -2954,7 +2961,7 @@ PerlIO_funcs PerlIO_stdio = {
     "stdio",
     sizeof(PerlIOStdio),
     PERLIO_K_BUFFERED|PERLIO_K_RAW,
-    PerlIOBase_pushed,
+    PerlIOStdio_pushed,
     PerlIOBase_popped,
     PerlIOStdio_open,
     PerlIOBase_binmode,         /* binmode */
@@ -4629,3 +4636,4 @@ PerlIO_sprintf(char *s, int n, const char *fmt, ...)
 
 
 
+