Adding upstream version 2.6.1.upstream/2.6.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 504 insertions, 0 deletions

diff --git a/apt-pkg/contrib/mmap.cc b/apt-pkg/contrib/mmap.cc
new file mode 100644
index 0000000..0568e1c
--- /dev/null
+++ b/apt-pkg/contrib/mmap.cc
@@ -0,0 +1,504 @@
+// -*- mode: cpp; mode: fold -*-
+// Description								/*{{{*/
+/* ######################################################################
+   
+   MMap Class - Provides 'real' mmap or a faked mmap using read().
+
+   MMap cover class.
+
+   Some broken versions of glibc2 (libc6) have a broken definition
+   of mmap that accepts a char * -- all other systems (and libc5) use
+   void *. We can't safely do anything here that would be portable, so
+   libc6 generates warnings -- which should be errors, g++ isn't properly
+   strict.
+   
+   ##################################################################### */
+									/*}}}*/
+// Include Files							/*{{{*/
+#define _DEFAULT_SOURCE
+#include <config.h>
+
+#include <apt-pkg/error.h>
+#include <apt-pkg/fileutl.h>
+#include <apt-pkg/macros.h>
+#include <apt-pkg/mmap.h>
+
+#include <cstdint>
+#include <cstring>
+#include <string>
+#include <errno.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <apti18n.h>
+									/*}}}*/
+
+// MMap::MMap - Constructor						/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+MMap::MMap(FileFd &F,unsigned long Flags) : Flags(Flags), iSize(0),
+                     Base(nullptr), SyncToFd(nullptr)
+{
+   if ((Flags & NoImmMap) != NoImmMap)
+      Map(F);
+}
+									/*}}}*/
+// MMap::MMap - Constructor						/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+MMap::MMap(unsigned long Flags) : Flags(Flags), iSize(0),
+                     Base(nullptr), SyncToFd(nullptr)
+{
+}
+									/*}}}*/
+// MMap::~MMap - Destructor						/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+MMap::~MMap()
+{
+   Close();
+}
+									/*}}}*/
+// MMap::Map - Perform the mapping					/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool MMap::Map(FileFd &Fd)
+{
+   iSize = Fd.Size();
+
+   // Set the permissions.
+   int Prot = PROT_READ;
+   int Map = MAP_SHARED;
+   if ((Flags & ReadOnly) != ReadOnly)
+      Prot |= PROT_WRITE;
+   if ((Flags & Public) != Public)
+      Map = MAP_PRIVATE;
+   
+   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 = malloc(iSize);
+      if (unlikely(Base == nullptr))
+	 return _error->Errno("MMap-compressed-malloc", _("Couldn't make mmap of %llu bytes"), iSize);
+      SyncToFd = new FileFd();
+      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 = (Flags & Fallback) ? MAP_FAILED : mmap(0,iSize,Prot,Map,Fd.Fd(),0);
+   if (Base == MAP_FAILED)
+   {
+      if (errno == ENODEV || errno == EINVAL || (Flags & Fallback))
+      {
+	 // 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 = malloc(iSize);
+	    if (unlikely(Base == nullptr))
+	       return _error->Errno("MMap-malloc", _("Couldn't make mmap of %llu bytes"), iSize);
+	    SyncToFd = new FileFd();
+	    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());
+
+	 Base = calloc(iSize, 1);
+	 if (unlikely(Base == nullptr))
+	    return _error->Errno("MMap-calloc", _("Couldn't make mmap of %llu bytes"), iSize);
+	 SyncToFd = new FileFd (dupped_fd);
+	 if (!SyncToFd->Seek(0L) || !SyncToFd->Read(Base, iSize))
+	    return false;
+      }
+      else
+	 return _error->Errno("MMap-mmap", _("Couldn't make mmap of %llu bytes"), iSize);
+     }
+
+   return true;
+}
+									/*}}}*/
+// MMap::Close - Close the map						/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool MMap::Close(bool DoSync)
+{
+   if ((Flags & UnMapped) == UnMapped || validData() == false || iSize == 0)
+      return true;
+   
+   if (DoSync == true)
+      Sync();
+
+   if (SyncToFd != NULL)
+   {
+      free(Base);
+      delete SyncToFd;
+      SyncToFd = NULL;
+   }
+   else
+   {
+      if (munmap((char *)Base, iSize) != 0)
+	 _error->WarningE("mmap", _("Unable to close mmap"));
+   }
+
+   iSize = 0;
+   Base = 0;
+   return true;
+}
+									/*}}}*/
+// MMap::Sync - Synchronize the map with the disk			/*{{{*/
+// ---------------------------------------------------------------------
+/* This is done in synchronous mode - the docs indicate that this will 
+   not return till all IO is complete */
+bool MMap::Sync()
+{
+   if ((Flags & UnMapped) == UnMapped)
+      return true;
+
+   if ((Flags & ReadOnly) != ReadOnly)
+   {
+      if (SyncToFd != NULL)
+      {
+	 if (!SyncToFd->Seek(0) || !SyncToFd->Write(Base, iSize))
+	    return false;
+      }
+      else
+      {
+#ifdef _POSIX_SYNCHRONIZED_IO
+	 if (msync((char *)Base, iSize, MS_SYNC) < 0)
+	    return _error->Errno("msync", _("Unable to synchronize mmap"));
+#endif
+      }
+   }
+   return true;
+}
+									/*}}}*/
+// MMap::Sync - Synchronize a section of the file to disk		/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+bool MMap::Sync(unsigned long Start,unsigned long Stop)
+{
+   if ((Flags & UnMapped) == UnMapped)
+      return true;
+
+   if ((Flags & ReadOnly) != ReadOnly)
+   {
+      if (SyncToFd != 0)
+      {
+	 if (!SyncToFd->Seek(0) ||
+	     !SyncToFd->Write (((char *)Base)+Start, Stop-Start))
+	    return false;
+      }
+      else
+      {
+#ifdef _POSIX_SYNCHRONIZED_IO
+	 unsigned long long const PSize = sysconf(_SC_PAGESIZE);
+	 if (msync((char *)Base+(Start/PSize)*PSize, Stop - Start, MS_SYNC) < 0)
+	    return _error->Errno("msync", _("Unable to synchronize mmap"));
+#endif
+      }
+   }
+   return true;
+}
+									/*}}}*/
+
+// DynamicMMap::DynamicMMap - Constructor				/*{{{*/
+// ---------------------------------------------------------------------
+/* */
+DynamicMMap::DynamicMMap(FileFd &F,unsigned long Flags,unsigned long const &Workspace,
+			 unsigned long const &Grow, unsigned long const &Limit) :
+		MMap(F,Flags | NoImmMap), Fd(&F), WorkSpace(Workspace),
+		GrowFactor(Grow), Limit(Limit)
+{
+   // disable Moveable if we don't grow
+   if (Grow == 0)
+      this->Flags &= ~Moveable;
+
+#ifndef __linux__
+   // kfreebsd doesn't have mremap, so we use the fallback
+   if ((this->Flags & Moveable) == Moveable)
+      this->Flags |= Fallback;
+#endif
+
+   unsigned long long EndOfFile = Fd->Size();
+   if (EndOfFile > WorkSpace)
+      WorkSpace = EndOfFile;
+   else if(WorkSpace > 0)
+   {
+      Fd->Seek(WorkSpace - 1);
+      char C = 0;
+      Fd->Write(&C,sizeof(C));
+   }
+   
+   Map(F);
+   iSize = EndOfFile;
+}
+									/*}}}*/
+// DynamicMMap::DynamicMMap - Constructor for a non-file backed map	/*{{{*/
+// ---------------------------------------------------------------------
+/* We try here to use mmap to reserve some space - this is much more
+   cooler than the fallback solution to simply allocate a char array
+   and could come in handy later than we are able to grow such an mmap */
+DynamicMMap::DynamicMMap(unsigned long Flags,unsigned long const &WorkSpace,
+			 unsigned long const &Grow, unsigned long const &Limit) :
+		MMap(Flags | NoImmMap | UnMapped), Fd(0), WorkSpace(WorkSpace),
+		GrowFactor(Grow), Limit(Limit)
+{
+	// disable Moveable if we don't grow
+	if (Grow == 0)
+		this->Flags &= ~Moveable;
+
+#ifndef __linux__
+	// kfreebsd doesn't have mremap, so we use the fallback
+	if ((this->Flags & Moveable) == Moveable)
+		this->Flags |= Fallback;
+#endif
+
+#ifdef _POSIX_MAPPED_FILES
+	if ((this->Flags & Fallback) != Fallback) {
+		// Set the permissions.
+		int Prot = PROT_READ;
+#ifdef MAP_ANONYMOUS
+		int Map = MAP_PRIVATE | MAP_ANONYMOUS;
+#else
+		int Map = MAP_PRIVATE | MAP_ANON;
+#endif
+		if ((this->Flags & ReadOnly) != ReadOnly)
+			Prot |= PROT_WRITE;
+		if ((this->Flags & Public) == Public)
+#ifdef MAP_ANONYMOUS
+			Map = MAP_SHARED | MAP_ANONYMOUS;
+#else
+			Map = MAP_SHARED | MAP_ANON;
+#endif
+
+		// use anonymous mmap() to get the memory
+		Base = (unsigned char*) mmap(0, WorkSpace, Prot, Map, -1, 0);
+
+		if(Base == MAP_FAILED)
+			_error->Errno("DynamicMMap",_("Couldn't make mmap of %lu bytes"),WorkSpace);
+
+		iSize = 0;
+		return;
+	}
+#endif
+	// fallback to a static allocated space
+	Base = calloc(WorkSpace, 1);
+	iSize = 0;
+}
+									/*}}}*/
+// DynamicMMap::~DynamicMMap - Destructor				/*{{{*/
+// ---------------------------------------------------------------------
+/* We truncate the file to the size of the memory data set */
+DynamicMMap::~DynamicMMap()
+{
+   if (Fd == 0)
+   {
+      if (validData() == false)
+	 return;
+#ifdef _POSIX_MAPPED_FILES
+      munmap(Base, WorkSpace);
+#else
+      free(Base);
+#endif
+      return;
+   }
+   
+   unsigned long long EndOfFile = iSize;
+   iSize = WorkSpace;
+   Close(false);
+   if(ftruncate(Fd->Fd(),EndOfFile) < 0)
+      _error->Errno("ftruncate", _("Failed to truncate file"));
+}  
+									/*}}}*/
+// DynamicMMap::RawAllocate - Allocate a raw chunk of unaligned space	/*{{{*/
+// ---------------------------------------------------------------------
+/* This allocates a block of memory aligned to the given size */
+unsigned long DynamicMMap::RawAllocate(unsigned long long Size,unsigned long Aln)
+{
+   unsigned long long Result = iSize;
+   if (Aln != 0)
+      Result += Aln - (iSize%Aln);
+
+   iSize = Result + Size;
+
+   // try to grow the buffer
+   while(Result + Size > WorkSpace)
+   {
+      if(!Grow())
+      {
+	 _error->Fatal(_("Dynamic MMap ran out of room. Please increase the size "
+			 "of APT::Cache-Start. Current value: %lu. (man 5 apt.conf)"), WorkSpace);
+	 return 0;
+      }
+   }
+   return Result;
+}
+									/*}}}*/
+// DynamicMMap::Allocate - Pooled aligned allocation			/*{{{*/
+// ---------------------------------------------------------------------
+/* This allocates an Item of size ItemSize so that it is aligned to its
+   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;
+   for (I = Pools; I != Pools + PoolCount; ++I)
+   {
+      if (I->ItemSize == ItemSize)
+	 break;
+   }
+   // No pool is allocated, use an unallocated one.
+   if (unlikely(I == Pools + PoolCount))
+   {
+      for (I = Pools; I != Pools + PoolCount; ++I)
+      {
+	 if (I->ItemSize == 0)
+	    break;
+      }
+      // Woops, we ran out, the calling code should allocate more.
+      if (I == Pools + PoolCount)
+      {
+	 _error->Error("Ran out of allocation pools");
+	 return 0;
+      }
+
+      I->ItemSize = ItemSize;
+      I->Count = 0;
+   }
+
+   unsigned long Result = 0;
+   // Out of space, allocate some more
+   if (I->Count == 0)
+   {
+      const unsigned long size = 20*1024;
+      I->Count = size/ItemSize;
+      Pool* oldPools = Pools;
+      _error->PushToStack();
+      Result = RawAllocate(size,ItemSize);
+      bool const newError = _error->PendingError();
+      _error->MergeWithStack();
+      if (Pools != oldPools)
+	 I = Pools + (I - oldPools);
+
+      // Does the allocation failed ?
+      if (Result == 0 && newError)
+	 return 0;
+      I->Start = Result;
+   }
+   else
+      Result = I->Start;
+
+   I->Count--;
+   I->Start += ItemSize;
+   return Result/ItemSize;
+}
+									/*}}}*/
+// DynamicMMap::WriteString - Write a string to the file		/*{{{*/
+// ---------------------------------------------------------------------
+/* Strings are aligned to 16 bytes */
+unsigned long DynamicMMap::WriteString(const char *String,
+				       unsigned long Len)
+{
+   if (Len == std::numeric_limits<unsigned long>::max())
+      Len = strlen(String);
+
+   _error->PushToStack();
+   unsigned long Result = RawAllocate(Len+1+sizeof(uint16_t),sizeof(uint16_t));
+   bool const newError = _error->PendingError();
+   _error->MergeWithStack();
+
+   if (Base == NULL || (Result == 0 && newError))
+      return 0;
+
+   if (Len >= std::numeric_limits<uint16_t>::max())
+      abort();
+
+   uint16_t LenToWrite = Len;
+   memcpy((char *)Base + Result, &LenToWrite, sizeof(LenToWrite));
+   Result += + sizeof(LenToWrite);
+
+   memcpy((char *)Base + Result,String,Len);
+   ((char *)Base)[Result + Len] = 0;
+   return Result;
+}
+									/*}}}*/
+// DynamicMMap::Grow - Grow the mmap					/*{{{*/
+// ---------------------------------------------------------------------
+/* This method is a wrapper around different methods to (try to) grow
+   a mmap (or our char[]-fallback). Encounterable environments:
+   1. Moveable + !Fallback + linux -> mremap with MREMAP_MAYMOVE
+   2. Moveable + !Fallback + !linux -> not possible (forbidden by constructor)
+   3. Moveable + Fallback -> realloc
+   4. !Moveable + !Fallback + linux -> mremap alone - which will fail in 99,9%
+   5. !Moveable + !Fallback + !linux -> not possible (forbidden by constructor)
+   6. !Moveable + Fallback -> not possible
+   [ While Moveable and Fallback stands for the equally named flags and
+     "linux" indicates a linux kernel instead of a freebsd kernel. ]
+   So what you can see here is, that a MMAP which want to be growable need
+   to be moveable to have a real chance but that this method will at least try
+   the nearly impossible 4 to grow it before it finally give up: Never say never. */
+bool DynamicMMap::Grow() {
+	if (Limit != 0 && WorkSpace >= Limit)
+		return _error->Error(_("Unable to increase the size of the MMap as the "
+		                       "limit of %lu bytes is already reached."), Limit);
+	if (GrowFactor <= 0)
+		return _error->Error(_("Unable to increase size of the MMap as automatic growing is disabled by user."));
+
+	unsigned long long const newSize = WorkSpace + GrowFactor;
+
+	if(Fd != 0) {
+		Fd->Seek(newSize - 1);
+		char C = 0;
+		Fd->Write(&C,sizeof(C));
+	}
+
+	unsigned long const poolOffset = Pools - ((Pool*) Base);
+
+	if ((Flags & Fallback) != Fallback) {
+#if defined(_POSIX_MAPPED_FILES) && defined(__linux__)
+   #ifdef MREMAP_MAYMOVE
+
+		if ((Flags & Moveable) == Moveable)
+			Base = mremap(Base, WorkSpace, newSize, MREMAP_MAYMOVE);
+		else
+   #endif
+			Base = mremap(Base, WorkSpace, newSize, 0);
+
+		if(Base == MAP_FAILED)
+			return false;
+#else
+		return false;
+#endif
+	} else {
+		if ((Flags & Moveable) != Moveable)
+			return false;
+
+		Base = realloc(Base, newSize);
+		if (Base == NULL)
+			return false;
+		else
+			/* Set new memory to 0 */
+			memset((char*)Base + WorkSpace, 0, newSize - WorkSpace);
+	}
+
+	Pools =(Pool*) Base + poolOffset;
+	WorkSpace = newSize;
+	return true;
+}
+									/*}}}*/