rework some code to fix some scan-build warnings

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

diff --git a/apt-pkg/contrib/mmap.cc b/apt-pkg/contrib/mmap.cc
index 3e6ef3520d2520705ec8eb5aae82b6bb7bc8d51b..51e8eb30f249e40878d0d743283cfe644b38a4de 100644 (file)
--- a/apt-pkg/contrib/mmap.cc
+++ b/apt-pkg/contrib/mmap.cc
@@ -156,11 +156,10 @@ bool MMap::Close(bool DoSync)
 /* This is done in syncronous mode - the docs indicate that this will 
    not return till all IO is complete */
 bool MMap::Sync()
-{   
+{
    if ((Flags & UnMapped) == UnMapped)
       return true;
-   
-#ifdef _POSIX_SYNCHRONIZED_IO   
+
    if ((Flags & ReadOnly) != ReadOnly)
    {
       if (SyncToFd != NULL)
@@ -170,11 +169,12 @@ bool MMap::Sync()
       }
       else
       {
+#ifdef _POSIX_SYNCHRONIZED_IO
         if (msync((char *)Base, iSize, MS_SYNC) < 0)
            return _error->Errno("msync", _("Unable to synchronize mmap"));
+#endif
       }
    }
-#endif   
    return true;
 }
                                                                        /*}}}*/
@@ -185,9 +185,7 @@ bool MMap::Sync(unsigned long Start,unsigned long Stop)
 {
    if ((Flags & UnMapped) == UnMapped)
       return true;
-   
-#ifdef _POSIX_SYNCHRONIZED_IO
-   unsigned long long PSize = sysconf(_SC_PAGESIZE);
+
    if ((Flags & ReadOnly) != ReadOnly)
    {
       if (SyncToFd != 0)
@@ -198,11 +196,13 @@ bool MMap::Sync(unsigned long Start,unsigned long Stop)
       }
       else
       {
+#ifdef _POSIX_SYNCHRONIZED_IO
+        unsigned long long const PSize = sysconf(_SC_PAGESIZE);
         if (msync((char *)Base+(unsigned long long)(Start/PSize)*PSize,Stop - Start,MS_SYNC) < 0)
            return _error->Errno("msync", _("Unable to synchronize mmap"));
+#endif
       }
    }
-#endif   
    return true;
 }
                                                                        /*}}}*/
@@ -352,6 +352,12 @@ unsigned long DynamicMMap::RawAllocate(unsigned long long Size,unsigned long Aln
    size in the file. */
 unsigned long DynamicMMap::Allocate(unsigned long ItemSize)
 {
+   if (unlikely(ItemSize == 0))
+   {
+      _error->Fatal("Can't allocate an item of size zero");
+      return 0;
+   }
+
    // Look for a matching pool entry
    Pool *I;
    Pool *Empty = 0;
@@ -412,7 +418,7 @@ unsigned long DynamicMMap::WriteString(const char *String,
 
    unsigned long const Result = RawAllocate(Len+1,0);
 
-   if (Result == 0 && _error->PendingError())
+   if (Base == NULL || (Result == 0 && _error->PendingError()))
       return 0;
 
    memcpy((char *)Base + Result,String,Len);