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authorMichael Vogt <michael.vogt@ubuntu.com>2010-02-18 15:07:56 +0100
committerMichael Vogt <michael.vogt@ubuntu.com>2010-02-18 15:07:56 +0100
commitb026dbb970c71213e12caaeb47bf7a27b91ea0a0 (patch)
tree68c68ff6bc12037ac74899f686fce9c0a3e419bd /apt-pkg/contrib/mmap.cc
parent07f2526e45f9978201817237745727db6177c29a (diff)
parentd328fd1a20543192a7ea3eac124f10a5793743e9 (diff)
* [BREAK] add possibility to download and use multiply
Translation files, configurable with Acquire::Translation (Closes: #444222, #448216, #550564) * Ignore :qualifiers after package name in build dependencies for now as long we don't understand them (Closes: #558103) * apt-pkg/contrib/mmap.{cc,h}: - extend it to have a growable flag - unused now but maybe... * apt-pkg/pkgcache.h: - use long instead of short for {Ver,Desc}File size, patch from Víctor Manuel Jáquez Leal, thanks! (Closes: #538917) * apt-pkg/acquire-item.cc: - allow also to skip the last patch if target is reached, thanks Bernhard R. Link! (Closes: #545699) * ftparchive/writer.{cc,h}: - add APT::FTPArchive::AlwaysStat to disable the too aggressive caching if versions are build multiply times (not recommend) Patch by Christoph Goehre, thanks! (Closes: #463260)
Diffstat (limited to 'apt-pkg/contrib/mmap.cc')
-rw-r--r--apt-pkg/contrib/mmap.cc127
1 files changed, 85 insertions, 42 deletions
diff --git a/apt-pkg/contrib/mmap.cc b/apt-pkg/contrib/mmap.cc
index 4d5fcf71e..f440f9489 100644
--- a/apt-pkg/contrib/mmap.cc
+++ b/apt-pkg/contrib/mmap.cc
@@ -140,8 +140,10 @@ bool MMap::Sync(unsigned long Start,unsigned long Stop)
// DynamicMMap::DynamicMMap - Constructor /*{{{*/
// ---------------------------------------------------------------------
/* */
-DynamicMMap::DynamicMMap(FileFd &F,unsigned long Flags,unsigned long WorkSpace) :
- MMap(F,Flags | NoImmMap), Fd(&F), WorkSpace(WorkSpace)
+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)
{
if (_error->PendingError() == true)
return;
@@ -165,32 +167,48 @@ DynamicMMap::DynamicMMap(FileFd &F,unsigned long Flags,unsigned long WorkSpace)
/* 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 WorkSpace) :
- MMap(Flags | NoImmMap | UnMapped), Fd(0), WorkSpace(WorkSpace)
+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)
{
- if (_error->PendingError() == true)
- return;
+ if (_error->PendingError() == true)
+ return;
+
+ // disable Moveable if we don't grow
+ if (Grow == 0)
+ Flags &= ~Moveable;
+
+#ifndef __linux__
+ // kfreebsd doesn't have mremap, so we use the fallback
+ if ((Flags & Moveable) == Moveable)
+ Flags |= Fallback;
+#endif
#ifdef _POSIX_MAPPED_FILES
- // Set the permissions.
- int Prot = PROT_READ;
- int Map = MAP_PRIVATE | MAP_ANONYMOUS;
- if ((Flags & ReadOnly) != ReadOnly)
- Prot |= PROT_WRITE;
- if ((Flags & Public) == Public)
- Map = MAP_SHARED | MAP_ANONYMOUS;
+ if ((Flags & Fallback) != Fallback) {
+ // Set the permissions.
+ int Prot = PROT_READ;
+ int Map = MAP_PRIVATE | MAP_ANONYMOUS;
+ if ((Flags & ReadOnly) != ReadOnly)
+ Prot |= PROT_WRITE;
+ if ((Flags & Public) == Public)
+ Map = MAP_SHARED | MAP_ANONYMOUS;
- // use anonymous mmap() to get the memory
- Base = (unsigned char*) mmap(0, WorkSpace, Prot, Map, -1, 0);
+ // 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);
-#else
- // fallback to a static allocated space
- Base = new unsigned char[WorkSpace];
- memset(Base,0,WorkSpace);
+ if(Base == MAP_FAILED)
+ _error->Errno("DynamicMMap",_("Couldn't make mmap of %lu bytes"),WorkSpace);
+
+ iSize = 0;
+ return;
+ }
#endif
- iSize = 0;
+ // fallback to a static allocated space
+ Base = new unsigned char[WorkSpace];
+ memset(Base,0,WorkSpace);
+ iSize = 0;
}
/*}}}*/
// DynamicMMap::~DynamicMMap - Destructor /*{{{*/
@@ -311,30 +329,55 @@ unsigned long DynamicMMap::WriteString(const char *String,
/*}}}*/
// DynamicMMap::Grow - Grow the mmap /*{{{*/
// ---------------------------------------------------------------------
-/* This method will try to grow the mmap we currently use. This doesn't
- work most of the time because we can't move the mmap around in the
- memory for now as this would require to adjust quite a lot of pointers
- but why we should not at least try to grow it before we give up? */
-bool DynamicMMap::Grow()
-{
-#if defined(_POSIX_MAPPED_FILES) && defined(__linux__)
- unsigned long newSize = WorkSpace + 1024*1024;
+/* 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(_("The size of a MMap has already reached the defined limit of %lu bytes,"
+ "abort the try to grow the MMap."), Limit);
- if(Fd != 0)
- {
- Fd->Seek(newSize - 1);
- char C = 0;
- Fd->Write(&C,sizeof(C));
- }
+ unsigned long const newSize = WorkSpace + 1024*1024;
- Base = mremap(Base, WorkSpace, newSize, 0);
- if(Base == MAP_FAILED)
- return false;
+ if(Fd != 0) {
+ Fd->Seek(newSize - 1);
+ char C = 0;
+ Fd->Write(&C,sizeof(C));
+ }
+ 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);
- WorkSpace = newSize;
- return true;
+ if(Base == MAP_FAILED)
+ return false;
#else
- return false;
+ return false;
#endif
+ } else {
+ if ((Flags & Moveable) != Moveable)
+ return false;
+
+ Base = realloc(Base, newSize);
+ if (Base == NULL)
+ return false;
+ }
+
+ WorkSpace = newSize;
+ return true;
}
/*}}}*/