Use sysconf() or getpagesize() to find out the pagesize.

p4raw-id: //depot/perl@7645

diff --git a/perlio.c b/perlio.c
index 0da8813..73e463a 100644 (file)
--- a/perlio.c
+++ b/perlio.c
@@ -1823,6 +1823,7 @@ static size_t page_size = 0;
 IV
 PerlIOMmap_map(PerlIO *f)
 {
+ dTHX;
  PerlIOMmap *m = PerlIOSelf(f,PerlIOMmap);
  PerlIOBuf  *b = &m->base;
  IV flags = PerlIOBase(f)->flags;
@@ -1841,8 +1842,40 @@ PerlIOMmap_map(PerlIO *f)
      if (len > 0)
       {
        Off_t posn;
-       if (!page_size)
+       if (!page_size) {
+#if defined(HAS_SYSCONF) && (defined(_SC_PAGESIZE) || defined(_SC_PAGE_SIZE))
+          {
+              SETERRNO(0,SS$_NORMAL);
+#   ifdef _SC_PAGESIZE
+              page_size = sysconf(_SC_PAGESIZE);
+#   else
+              page_size = sysconf(_SC_PAGE_SIZE);
+#   endif 
+              if ((long)page_size < 0) {
+                  if (errno) {
+                      SV *error = ERRSV;
+                      char *msg;
+                      STRLEN n_a;
+                      (void)SvUPGRADE(error, SVt_PV);
+                      msg = SvPVx(error, n_a);
+                      Perl_croak("panic: sysconf: %s", msg);
+                  }
+                  else
+                      Perl_croak("panic: sysconf: pagesize unknown");
+              }
+          }
+#else
+#   ifdef HAS_GETPAGESIZE
         page_size = getpagesize();
+#   else
+#       if defined(I_SYS_PARAM) && defined(PAGESIZE)
+        page_size = PAGESIZE; /* compiletime, bad */
+#       endif
+#   endif
+#endif
+       if ((IV)page_size <= 0)
+           Perl_croak("panic: bad pagesize %"IVdf, (IV)page_size);
+       }
        if (b->posn < 0)
         {
          /* This is a hack - should never happen - open should have set it ! */