Sync

[apt.git] / apt-pkg / contrib / mmap.cc

diff --git a/apt-pkg/contrib/mmap.cc b/apt-pkg/contrib/mmap.cc
index 85cac1cca7737bdb2d38eb7f25c0b10d8110a7df..e12e077c61c2efb958415971a2a1ff4df03aa467 100644 (file)
--- a/apt-pkg/contrib/mmap.cc
+++ b/apt-pkg/contrib/mmap.cc
@@ -1,6 +1,6 @@
 // -*- mode: cpp; mode: fold -*-
 // Description                                                         /*{{{*/
-// $Id: mmap.cc,v 1.1 1998/07/02 02:58:13 jgg Exp $
+// $Id: mmap.cc,v 1.8 1998/07/26 04:49:34 jgg Exp $
 /* ######################################################################
    
    MMap Class - Provides 'real' mmap or a faked mmap using read().
@@ -21,9 +21,13 @@
    ##################################################################### */
                                                                        /*}}}*/
 // Include Files                                                       /*{{{*/
+#ifdef __GNUG__
+#pragma implementation "apt-pkg/mmap.h"
+#endif 
+
 #define _BSD_SOURCE
-#include <pkglib/mmap.h>
-#include <pkglib/error.h>
+#include <apt-pkg/mmap.h>
+#include <apt-pkg/error.h>
 
 #include <sys/mman.h>
 #include <sys/stat.h>
@@ -35,7 +39,7 @@
 // MMap::MMap - Constructor                                            /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-MMap::MMap(File &F,unsigned long Flags) : Fd(F), Flags(Flags), iSize(0),
+MMap::MMap(FileFd &F,unsigned long Flags) : Fd(F), Flags(Flags), iSize(0),
                      Base(0)
 {
    if ((Flags & NoImmMap) != NoImmMap)
@@ -65,6 +69,9 @@ bool MMap::Map()
    if ((Flags & Public) != Public)
       Map = MAP_PRIVATE;
    
+   if (iSize == 0)
+      return _error->Error("Can't mmap an empty file");
+   
    // Map it.
    Base = mmap(0,iSize,Prot,Map,Fd.Fd(),0);
    if (Base == (void *)-1)
@@ -76,12 +83,13 @@ bool MMap::Map()
 // MMap::Close - Close the map                                         /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-bool MMap::Close(bool DoClose)
+bool MMap::Close(bool DoClose, bool DoSync)
 {
    if (Fd.IsOpen() == false)
       return true;
 
-   Sync();
+   if (DoSync == true)
+      Sync();
    
    if (munmap((char *)Base,iSize) != 0)
       _error->Warning("Unable to munmap");
@@ -94,10 +102,11 @@ bool MMap::Close(bool DoClose)
                                                                        /*}}}*/
 // MMap::Sync - Syncronize the map with the disk                       /*{{{*/
 // ---------------------------------------------------------------------
-/* */
+/* This is done in syncronous mode - the docs indicate that this will 
+   not return till all IO is complete */
 bool MMap::Sync()
 {   
-   if ((Flags & ReadOnly) == ReadOnly)
+   if ((Flags & ReadOnly) != ReadOnly)
       if (msync((char *)Base,iSize,MS_SYNC) != 0)
         return _error->Error("msync","Unable to write mmap");
    return true;
@@ -108,7 +117,7 @@ bool MMap::Sync()
 /* */
 bool MMap::Sync(unsigned long Start,unsigned long Stop)
 {
-   if ((Flags & ReadOnly) == ReadOnly)
+   if ((Flags & ReadOnly) != ReadOnly)
       if (msync((char *)Base+(int)(Start/PAGE_SIZE)*PAGE_SIZE,Stop - Start,MS_SYNC) != 0)
         return _error->Error("msync","Unable to write mmap");
    return true;
@@ -118,7 +127,7 @@ bool MMap::Sync(unsigned long Start,unsigned long Stop)
 // DynamicMMap::DynamicMMap - Constructor                              /*{{{*/
 // ---------------------------------------------------------------------
 /* */
-DynamicMMap::DynamicMMap(File &F,unsigned long Flags,unsigned long WorkSpace) : 
+DynamicMMap::DynamicMMap(FileFd &F,unsigned long Flags,unsigned long WorkSpace) : 
              MMap(F,Flags | NoImmMap), WorkSpace(WorkSpace)
 {
    unsigned long EndOfFile = Fd.Size();
@@ -135,18 +144,23 @@ DynamicMMap::DynamicMMap(File &F,unsigned long Flags,unsigned long WorkSpace) :
 DynamicMMap::~DynamicMMap()
 {
    unsigned long EndOfFile = iSize;
-   Close(false);
+   Sync();
+   iSize = WorkSpace;
+   Close(false,false);
    ftruncate(Fd.Fd(),EndOfFile);
    Fd.Close();
 }  
                                                                        /*}}}*/
 // DynamicMMap::RawAllocate - Allocate a raw chunk of unaligned space  /*{{{*/
 // ---------------------------------------------------------------------
-/* */
-unsigned long DynamicMMap::RawAllocate(unsigned long Size)
+/* This allocates a block of memory aligned to the given size */
+unsigned long DynamicMMap::RawAllocate(unsigned long Size,unsigned long Aln)
 {
    unsigned long Result = iSize;
-   iSize += Size;
+   if (Aln != 0)
+      Result += Aln - (iSize%Aln);
+   
+   iSize = Result + Size;
    
    // Just in case error check
    if (Result > WorkSpace)
@@ -154,7 +168,6 @@ unsigned long DynamicMMap::RawAllocate(unsigned long Size)
       _error->Error("Dynamic MMap ran out of room");
       return 0;
    }
-
    return Result;
 }
                                                                        /*}}}*/
@@ -194,9 +207,9 @@ unsigned long DynamicMMap::Allocate(unsigned long ItemSize)
    if (I->Count == 0)
    {
       I->Count = 20*1024/ItemSize;
-      I->Start = RawAllocate(I->Count*ItemSize);
+      I->Start = RawAllocate(I->Count*ItemSize,ItemSize);
    }   
-   
+
    I->Count--;
    unsigned long Result = I->Start;
    I->Start += ItemSize;