ChangeLogTag:Sun Jan 13 18:59:37 2002 Douglas C. Schmidt <schmidt@macarena.cs.wustl.edu>

5 files changed, 62 insertions, 9 deletions

diff --git a/ChangeLog b/ChangeLog
index 76d622d2019..279933a504f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Sun Jan 13 18:59:37 2002  Douglas C. Schmidt  <schmidt@macarena.cs.wustl.edu>
+
+	* ace/Memory_Pool.{h,cpp}: Added a new option that makes is possible
+	  to control whether or not a fixed address will be used when
+ 	  remapping a memory-mapped file.  Thanks to Jonathan Reis
+ 	  <reis@stentor.com> for this enhancement.
+
 Mon Jan 14 11:02:12 2002  Johnny Willemsen <jwillemsen@remedy.nl>
 
         * include/makeinclude/ace_flags.bor:
diff --git a/ChangeLogs/ChangeLog-02a b/ChangeLogs/ChangeLog-02a
index 76d622d2019..279933a504f 100644
--- a/ChangeLogs/ChangeLog-02a
+++ b/ChangeLogs/ChangeLog-02a
@@ -1,3 +1,10 @@
+Sun Jan 13 18:59:37 2002  Douglas C. Schmidt  <schmidt@macarena.cs.wustl.edu>
+
+	* ace/Memory_Pool.{h,cpp}: Added a new option that makes is possible
+	  to control whether or not a fixed address will be used when
+ 	  remapping a memory-mapped file.  Thanks to Jonathan Reis
+ 	  <reis@stentor.com> for this enhancement.
+
 Mon Jan 14 11:02:12 2002  Johnny Willemsen <jwillemsen@remedy.nl>
 
         * include/makeinclude/ace_flags.bor:
diff --git a/ChangeLogs/ChangeLog-03a b/ChangeLogs/ChangeLog-03a
index 76d622d2019..279933a504f 100644
--- a/ChangeLogs/ChangeLog-03a
+++ b/ChangeLogs/ChangeLog-03a
@@ -1,3 +1,10 @@
+Sun Jan 13 18:59:37 2002  Douglas C. Schmidt  <schmidt@macarena.cs.wustl.edu>
+
+	* ace/Memory_Pool.{h,cpp}: Added a new option that makes is possible
+	  to control whether or not a fixed address will be used when
+ 	  remapping a memory-mapped file.  Thanks to Jonathan Reis
+ 	  <reis@stentor.com> for this enhancement.
+
 Mon Jan 14 11:02:12 2002  Johnny Willemsen <jwillemsen@remedy.nl>
 
         * include/makeinclude/ace_flags.bor:
diff --git a/ace/Memory_Pool.cpp b/ace/Memory_Pool.cpp
index 5a0fe63fabe..1cc7cee6b3a 100644
--- a/ace/Memory_Pool.cpp
+++ b/ace/Memory_Pool.cpp
@@ -15,7 +15,7 @@
 #include "ace/Based_Pointer_Repository.h"
 #endif /* ACE_HAS_POSITION_INDEPENDENT_POINTERS == 1  */
 
-ACE_RCSID(ace, Memory_Pool, "$Id$")
+ACE_RCSID(ace, Memory_Pool, "Memory_Pool.cpp,v 4.79 2001/09/02 22:33:16 schmidt Exp")
 
 ACE_ALLOC_HOOK_DEFINE(ACE_Local_Memory_Pool)
 
@@ -153,6 +153,7 @@ ACE_MMAP_Memory_Pool::protect (void *addr, size_t len, int prot)
 ACE_MMAP_Memory_Pool::ACE_MMAP_Memory_Pool (const ACE_TCHAR *backing_store_name,
                                             const OPTIONS *options)
   : base_addr_ (0),
+    use_fixed_addr_(0),
     flags_ (MAP_SHARED),
     write_each_page_ (0),
     minimum_bytes_ (0),
@@ -171,17 +172,18 @@ ACE_MMAP_Memory_Pool::ACE_MMAP_Memory_Pool (const ACE_TCHAR *backing_store_name,
       else
         // If no options are specified, default to true.
         guess_on_fault_ = 1;
-#endif
+#endif /* (defined (ACE_HAS_SIGINFO_T) && !defined (ACE_LACKS_SI_ADDR)) || defined (ACE_WIN32) */
 
   // Only change the defaults if <options> != 0.
   if (options)
     {
       if (options->flags_ != 0)
         this->flags_ = options->flags_;
-      if (options->use_fixed_addr_)
+      use_fixed_addr_ = options->use_fixed_addr_;
+
+      if (use_fixed_addr_ == ACE_MMAP_Memory_Pool_Options::ALWAYS_FIXED)
         {
-          this->base_addr_ =
-            ACE_const_cast (void *, options->base_addr_);
+          this->base_addr_ = ACE_const_cast (void *, options->base_addr_);
           ACE_SET_BITS (flags_, MAP_FIXED);
         }
       this->write_each_page_ = options->write_each_page_;
@@ -286,6 +288,11 @@ ACE_MMAP_Memory_Pool::map_file (off_t map_size)
   // Unmap the existing mapping.
   this->mmap_.unmap ();
 
+#if (ACE_HAS_POSITION_INDEPENDENT_POINTERS == 1)
+  if(use_fixed_addr_ == ACE_MMAP_Memory_Pool_Options::NEVER_FIXED)
+    this->base_addr_ = 0;
+#endif /* ACE_HAS_POSITION_INDEPENDENT_POINTERS == 1 */
+
   // Remap the file.
   if (this->mmap_.map (map_size,
                        PROT_RDWR,
@@ -441,7 +448,7 @@ ACE_MMAP_Memory_Pool_Options::ACE_MMAP_Memory_Pool_Options (const void *base_add
                                                             int guess_on_fault,
                                                             LPSECURITY_ATTRIBUTES sa)
   : base_addr_ (base_addr),
-    use_fixed_addr_ (base_addr == 0 ? 0 : use_fixed_addr),
+    use_fixed_addr_ (use_fixed_addr),
     write_each_page_ (write_each_page),
     minimum_bytes_ (minimum_bytes),
     flags_ (flags),
@@ -449,6 +456,10 @@ ACE_MMAP_Memory_Pool_Options::ACE_MMAP_Memory_Pool_Options (const void *base_add
     sa_ (sa)
 {
   ACE_TRACE ("ACE_MMAP_Memory_Pool_Options::ACE_MMAP_Memory_Pool_Options");
+  // for backwards compatability
+  if (base_addr_ == 0 && use_fixed_addr_ == ALWAYS_FIXED)
+    use_fixed_addr_ = FIRSTCALL_FIXED;
+    
   // HP-UX 11, 64-bit bug workaround.
 #if defined (__hpux) && defined (__LP64__)
   long temp = ACE_DEFAULT_BASE_ADDRL;
diff --git a/ace/Memory_Pool.h b/ace/Memory_Pool.h
index 896887bc886..3a824cf6f12 100644
--- a/ace/Memory_Pool.h
+++ b/ace/Memory_Pool.h
@@ -1,11 +1,12 @@
 /* -*- C++ -*- */
+
 //=============================================================================
 /**
  *  @file     Memory_Pool.h
  *
  *  $Id$
  *
- *  @author Douglas C. Schmidt <schmidt@cs.wustl.edu> and Prashant Jain <pjain@cs.wustl.edu>
+ *  @author Dougls C. Schmidt <schmidt@cs.wustl.edu> and Prashant Jain <pjain@cs.wustl.edu>
  */
 //=============================================================================
 
@@ -382,9 +383,16 @@ protected:
 class ACE_Export ACE_MMAP_Memory_Pool_Options
 {
 public:
+  enum 
+  {
+    FIRSTCALL_FIXED = 0,
+    ALWAYS_FIXED = 1,
+    NEVER_FIXED = 2
+  };
+
   // = Initialization method.
   ACE_MMAP_Memory_Pool_Options (const void *base_addr = ACE_DEFAULT_BASE_ADDR,
-                                int use_fixed_addr = 1,
+                                int use_fixed_addr = ALWAYS_FIXED,
                                 int write_each_page = 1,
                                 off_t minimum_bytes = 0,
                                 u_int flags = 0,
@@ -394,7 +402,17 @@ public:
   /// Base address of the memory-mapped backing store.
   const void *base_addr_;
 
-  /// Must we use the <base_addr_> or can we let mmap(2) select it?
+  /** Determines whether we set <base_addr_> or if mmap(2) selects it
+  * FIRSTCALL_FIXED The base address from the first call to mmap
+  *                 will be used for subsequent calls to mmap
+  * ALWAYS_FIXED    The base address specified in base_addr will be
+  *                 used in all calls to mmap.
+  * NEVER_FIXED     The base address will be selected by the OS for
+  *                 each call to mmap. Caution should be used with
+  *                 this mode since a call that requires the backing
+  *                 store to grow may change pointers that are
+  *                 cached by the application.
+  */
   int use_fixed_addr_;
 
   /// Should each page be written eagerly to avoid surprises later
@@ -535,6 +553,9 @@ protected:
    */
   void *base_addr_;
 
+  /// Must we use the <base_addr_> or can we let mmap(2) select it?
+  int use_fixed_addr_;
+
   /// Flags passed into <ACE_OS::mmap>.
   int flags_;