improve error reporting in case of errors in combination with zlib

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

diff --git a/apt-pkg/contrib/mmap.cc b/apt-pkg/contrib/mmap.cc
index a110a70195cd39783705f2f6096dbd69645f609f..160718ea5ae503caf1848afd63514fbeae0d9a4d 100644 (file)
--- a/apt-pkg/contrib/mmap.cc
+++ b/apt-pkg/contrib/mmap.cc
@@ -21,6 +21,7 @@
 
 #include <apt-pkg/mmap.h>
 #include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
 
 #include <sys/mman.h>
 #include <sys/stat.h>
@@ -65,7 +66,7 @@ MMap::~MMap()
 bool MMap::Map(FileFd &Fd)
 {
    iSize = Fd.Size();
-   
+
    // Set the permissions.
    int Prot = PROT_READ;
    int Map = MAP_SHARED;
@@ -76,7 +77,18 @@ bool MMap::Map(FileFd &Fd)
    
    if (iSize == 0)
       return _error->Error(_("Can't mmap an empty file"));
-   
+
+   // We can't mmap compressed fd's directly, so we need to read it completely
+   if (Fd.IsCompressed() == true)
+   {
+      if ((Flags & ReadOnly) != ReadOnly)
+        return _error->Error("Compressed file %s can only be mapped readonly", Fd.Name().c_str());
+      Base = new unsigned char[iSize];
+      if (Fd.Seek(0L) == false || Fd.Read(Base, iSize) == false)
+        return _error->Error("Compressed file %s can't be read into mmap", Fd.Name().c_str());
+      return true;
+   }
+
    // Map it.
    Base = mmap(0,iSize,Prot,Map,Fd.Fd(),0);
    if (Base == (void *)-1)
@@ -85,6 +97,13 @@ bool MMap::Map(FileFd &Fd)
       {
         // The filesystem doesn't support this particular kind of mmap.
         // So we allocate a buffer and read the whole file into it.
+        if ((Flags & ReadOnly) == ReadOnly)
+        {
+           // for readonly, we don't need sync, so make it simple
+           Base = new unsigned char[iSize];
+           return Fd.Read(Base, iSize);
+        }
+        // FIXME: Writing to compressed fd's ?
         int const dupped_fd = dup(Fd.Fd());
         if (dupped_fd == -1)
            return _error->Errno("mmap", _("Couldn't duplicate file descriptor %i"), Fd.Fd());