tenfourfox/dom/cache/FileUtils.cpp
Cameron Kaiser c9b2922b70 hello FPR
2017-04-19 00:56:45 -07:00

502 lines
14 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/dom/cache/FileUtils.h"
#include "mozilla/dom/quota/FileStreams.h"
#include "mozilla/SnappyCompressOutputStream.h"
#include "mozilla/unused.h"
#include "nsIFile.h"
#include "nsIUUIDGenerator.h"
#include "nsNetCID.h"
#include "nsISimpleEnumerator.h"
#include "nsServiceManagerUtils.h"
#include "nsString.h"
#include "nsThreadUtils.h"
namespace mozilla {
namespace dom {
namespace cache {
using mozilla::dom::quota::FileInputStream;
using mozilla::dom::quota::FileOutputStream;
using mozilla::dom::quota::PERSISTENCE_TYPE_DEFAULT;
namespace {
enum BodyFileType
{
BODY_FILE_FINAL,
BODY_FILE_TMP
};
nsresult
BodyIdToFile(nsIFile* aBaseDir, const nsID& aId, BodyFileType aType,
nsIFile** aBodyFileOut);
} // namespace
// static
nsresult
BodyCreateDir(nsIFile* aBaseDir)
{
MOZ_ASSERT(aBaseDir);
nsCOMPtr<nsIFile> aBodyDir;
nsresult rv = aBaseDir->Clone(getter_AddRefs(aBodyDir));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = aBodyDir->Append(NS_LITERAL_STRING("morgue"));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = aBodyDir->Create(nsIFile::DIRECTORY_TYPE, 0755);
if (rv == NS_ERROR_FILE_ALREADY_EXISTS) {
return NS_OK;
}
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
return rv;
}
// static
nsresult
BodyDeleteDir(nsIFile* aBaseDir)
{
MOZ_ASSERT(aBaseDir);
nsCOMPtr<nsIFile> aBodyDir;
nsresult rv = aBaseDir->Clone(getter_AddRefs(aBodyDir));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = aBodyDir->Append(NS_LITERAL_STRING("morgue"));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = aBodyDir->Remove(/* recursive = */ true);
if (rv == NS_ERROR_FILE_NOT_FOUND ||
rv == NS_ERROR_FILE_TARGET_DOES_NOT_EXIST) {
rv = NS_OK;
}
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
return rv;
}
// static
nsresult
BodyGetCacheDir(nsIFile* aBaseDir, const nsID& aId, nsIFile** aCacheDirOut)
{
MOZ_ASSERT(aBaseDir);
MOZ_ASSERT(aCacheDirOut);
*aCacheDirOut = nullptr;
nsresult rv = aBaseDir->Clone(aCacheDirOut);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
MOZ_ASSERT(*aCacheDirOut);
rv = (*aCacheDirOut)->Append(NS_LITERAL_STRING("morgue"));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
// Some file systems have poor performance when there are too many files
// in a single directory. Mitigate this issue by spreading the body
// files out into sub-directories. We use the last byte of the ID for
// the name of the sub-directory.
nsAutoString subDirName;
subDirName.AppendInt(aId.m3[7]);
rv = (*aCacheDirOut)->Append(subDirName);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = (*aCacheDirOut)->Create(nsIFile::DIRECTORY_TYPE, 0755);
if (rv == NS_ERROR_FILE_ALREADY_EXISTS) {
return NS_OK;
}
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
return rv;
}
// static
nsresult
BodyStartWriteStream(const QuotaInfo& aQuotaInfo,
nsIFile* aBaseDir, nsIInputStream* aSource,
void* aClosure,
nsAsyncCopyCallbackFun aCallback, nsID* aIdOut,
nsISupports** aCopyContextOut)
{
MOZ_ASSERT(aBaseDir);
MOZ_ASSERT(aSource);
MOZ_ASSERT(aClosure);
MOZ_ASSERT(aCallback);
MOZ_ASSERT(aIdOut);
MOZ_ASSERT(aCopyContextOut);
nsresult rv;
nsCOMPtr<nsIUUIDGenerator> idGen =
do_GetService("@mozilla.org/uuid-generator;1", &rv);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = idGen->GenerateUUIDInPlace(aIdOut);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
nsCOMPtr<nsIFile> finalFile;
rv = BodyIdToFile(aBaseDir, *aIdOut, BODY_FILE_FINAL,
getter_AddRefs(finalFile));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
bool exists;
rv = finalFile->Exists(&exists);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
if (NS_WARN_IF(exists)) { return NS_ERROR_FILE_ALREADY_EXISTS; }
nsCOMPtr<nsIFile> tmpFile;
rv = BodyIdToFile(aBaseDir, *aIdOut, BODY_FILE_TMP, getter_AddRefs(tmpFile));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = tmpFile->Exists(&exists);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
if (NS_WARN_IF(exists)) { return NS_ERROR_FILE_ALREADY_EXISTS; }
nsCOMPtr<nsIOutputStream> fileStream =
FileOutputStream::Create(PERSISTENCE_TYPE_DEFAULT, aQuotaInfo.mGroup,
aQuotaInfo.mOrigin, tmpFile);
if (NS_WARN_IF(!fileStream)) { return NS_ERROR_UNEXPECTED; }
RefPtr<SnappyCompressOutputStream> compressed =
new SnappyCompressOutputStream(fileStream);
nsCOMPtr<nsIEventTarget> target =
do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID);
rv = NS_AsyncCopy(aSource, compressed, target, NS_ASYNCCOPY_VIA_WRITESEGMENTS,
compressed->BlockSize(), aCallback, aClosure,
true, true, // close streams
aCopyContextOut);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
return rv;
}
// static
void
BodyCancelWrite(nsIFile* aBaseDir, nsISupports* aCopyContext)
{
MOZ_ASSERT(aBaseDir);
MOZ_ASSERT(aCopyContext);
nsresult rv = NS_CancelAsyncCopy(aCopyContext, NS_ERROR_ABORT);
Unused << NS_WARN_IF(NS_FAILED(rv));
// The partially written file must be cleaned up after the async copy
// makes its callback.
}
// static
nsresult
BodyFinalizeWrite(nsIFile* aBaseDir, const nsID& aId)
{
MOZ_ASSERT(aBaseDir);
nsCOMPtr<nsIFile> tmpFile;
nsresult rv = BodyIdToFile(aBaseDir, aId, BODY_FILE_TMP, getter_AddRefs(tmpFile));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
nsCOMPtr<nsIFile> finalFile;
rv = BodyIdToFile(aBaseDir, aId, BODY_FILE_FINAL, getter_AddRefs(finalFile));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
nsAutoString finalFileName;
rv = finalFile->GetLeafName(finalFileName);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = tmpFile->RenameTo(nullptr, finalFileName);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
return rv;
}
// static
nsresult
BodyOpen(const QuotaInfo& aQuotaInfo, nsIFile* aBaseDir, const nsID& aId,
nsIInputStream** aStreamOut)
{
MOZ_ASSERT(aBaseDir);
MOZ_ASSERT(aStreamOut);
nsCOMPtr<nsIFile> finalFile;
nsresult rv = BodyIdToFile(aBaseDir, aId, BODY_FILE_FINAL,
getter_AddRefs(finalFile));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
bool exists;
rv = finalFile->Exists(&exists);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
if (NS_WARN_IF(!exists)) { return NS_ERROR_FILE_NOT_FOUND; }
nsCOMPtr<nsIInputStream> fileStream =
FileInputStream::Create(PERSISTENCE_TYPE_DEFAULT, aQuotaInfo.mGroup,
aQuotaInfo.mOrigin, finalFile);
if (NS_WARN_IF(!fileStream)) { return NS_ERROR_UNEXPECTED; }
fileStream.forget(aStreamOut);
return rv;
}
// static
nsresult
BodyDeleteFiles(nsIFile* aBaseDir, const nsTArray<nsID>& aIdList)
{
nsresult rv = NS_OK;
for (uint32_t i = 0; i < aIdList.Length(); ++i) {
nsCOMPtr<nsIFile> tmpFile;
rv = BodyIdToFile(aBaseDir, aIdList[i], BODY_FILE_TMP,
getter_AddRefs(tmpFile));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = tmpFile->Remove(false /* recursive */);
if (rv == NS_ERROR_FILE_NOT_FOUND ||
rv == NS_ERROR_FILE_TARGET_DOES_NOT_EXIST) {
rv = NS_OK;
}
// Only treat file deletion as a hard failure in DEBUG builds. Users
// can unfortunately hit this on windows if anti-virus is scanning files,
// etc.
MOZ_ASSERT(NS_SUCCEEDED(rv));
nsCOMPtr<nsIFile> finalFile;
rv = BodyIdToFile(aBaseDir, aIdList[i], BODY_FILE_FINAL,
getter_AddRefs(finalFile));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = finalFile->Remove(false /* recursive */);
if (rv == NS_ERROR_FILE_NOT_FOUND ||
rv == NS_ERROR_FILE_TARGET_DOES_NOT_EXIST) {
rv = NS_OK;
}
// Again, only treat removal as hard failure in debug build.
MOZ_ASSERT(NS_SUCCEEDED(rv));
}
return NS_OK;
}
namespace {
nsresult
BodyIdToFile(nsIFile* aBaseDir, const nsID& aId, BodyFileType aType,
nsIFile** aBodyFileOut)
{
MOZ_ASSERT(aBaseDir);
MOZ_ASSERT(aBodyFileOut);
*aBodyFileOut = nullptr;
nsresult rv = BodyGetCacheDir(aBaseDir, aId, aBodyFileOut);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
MOZ_ASSERT(*aBodyFileOut);
char idString[NSID_LENGTH];
aId.ToProvidedString(idString);
NS_ConvertASCIItoUTF16 fileName(idString);
if (aType == BODY_FILE_FINAL) {
fileName.AppendLiteral(".final");
} else {
fileName.AppendLiteral(".tmp");
}
rv = (*aBodyFileOut)->Append(fileName);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
return rv;
}
} // namespace
nsresult
BodyDeleteOrphanedFiles(nsIFile* aBaseDir, nsTArray<nsID>& aKnownBodyIdList)
{
MOZ_ASSERT(aBaseDir);
// body files are stored in a directory structure like:
//
// /morgue/01/{01fdddb2-884d-4c3d-95ba-0c8062f6c325}.final
// /morgue/02/{02fdddb2-884d-4c3d-95ba-0c8062f6c325}.tmp
nsCOMPtr<nsIFile> dir;
nsresult rv = aBaseDir->Clone(getter_AddRefs(dir));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
// Add the root morgue directory
rv = dir->Append(NS_LITERAL_STRING("morgue"));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
nsCOMPtr<nsISimpleEnumerator> entries;
rv = dir->GetDirectoryEntries(getter_AddRefs(entries));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
// Iterate over all the intermediate morgue subdirs
bool hasMore = false;
while (NS_SUCCEEDED(rv = entries->HasMoreElements(&hasMore)) && hasMore) {
nsCOMPtr<nsISupports> entry;
rv = entries->GetNext(getter_AddRefs(entry));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
nsCOMPtr<nsIFile> subdir = do_QueryInterface(entry);
bool isDir = false;
rv = subdir->IsDirectory(&isDir);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
// If a file got in here somehow, try to remove it and move on
if (NS_WARN_IF(!isDir)) {
rv = subdir->Remove(false /* recursive */);
MOZ_ASSERT(NS_SUCCEEDED(rv));
continue;
}
nsCOMPtr<nsISimpleEnumerator> subEntries;
rv = subdir->GetDirectoryEntries(getter_AddRefs(subEntries));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
// Now iterate over all the files in the subdir
bool subHasMore = false;
while(NS_SUCCEEDED(rv = subEntries->HasMoreElements(&subHasMore)) &&
subHasMore) {
nsCOMPtr<nsISupports> subEntry;
rv = subEntries->GetNext(getter_AddRefs(subEntry));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
nsCOMPtr<nsIFile> file = do_QueryInterface(subEntry);
nsAutoCString leafName;
rv = file->GetNativeLeafName(leafName);
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
// Delete all tmp files regardless of known bodies. These are
// all considered orphans.
if (StringEndsWith(leafName, NS_LITERAL_CSTRING(".tmp"))) {
// remove recursively in case its somehow a directory
rv = file->Remove(true /* recursive */);
MOZ_ASSERT(NS_SUCCEEDED(rv));
continue;
}
nsCString suffix(NS_LITERAL_CSTRING(".final"));
// Otherwise, it must be a .final file. If its not, then just
// skip it.
if (NS_WARN_IF(!StringEndsWith(leafName, suffix) ||
leafName.Length() != NSID_LENGTH - 1 + suffix.Length())) {
continue;
}
// Finally, parse the uuid out of the name. If its fails to parse,
// the ignore the file.
nsID id;
if (NS_WARN_IF(!id.Parse(leafName.BeginReading()))) {
continue;
}
if (!aKnownBodyIdList.Contains(id)) {
// remove recursively in case its somehow a directory
rv = file->Remove(true /* recursive */);
MOZ_ASSERT(NS_SUCCEEDED(rv));
}
}
}
return rv;
}
namespace {
nsresult
GetMarkerFileHandle(const QuotaInfo& aQuotaInfo, nsIFile** aFileOut)
{
MOZ_ASSERT(aFileOut);
nsCOMPtr<nsIFile> marker;
nsresult rv = aQuotaInfo.mDir->Clone(getter_AddRefs(marker));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = marker->Append(NS_LITERAL_STRING("cache"));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = marker->Append(NS_LITERAL_STRING("context_open.marker"));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
marker.forget(aFileOut);
return rv;
}
} // namespace
nsresult
CreateMarkerFile(const QuotaInfo& aQuotaInfo)
{
nsCOMPtr<nsIFile> marker;
nsresult rv = GetMarkerFileHandle(aQuotaInfo, getter_AddRefs(marker));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = marker->Create(nsIFile::NORMAL_FILE_TYPE, 0644);
if (rv == NS_ERROR_FILE_ALREADY_EXISTS) {
rv = NS_OK;
}
// Note, we don't need to fsync here. We only care about actually
// writing the marker if later modifications to the Cache are
// actually flushed to the disk. If the OS crashes before the marker
// is written then we are ensured no other changes to the Cache were
// flushed either.
return rv;
}
nsresult
DeleteMarkerFile(const QuotaInfo& aQuotaInfo)
{
nsCOMPtr<nsIFile> marker;
nsresult rv = GetMarkerFileHandle(aQuotaInfo, getter_AddRefs(marker));
if (NS_WARN_IF(NS_FAILED(rv))) { return rv; }
rv = marker->Remove(/* recursive = */ false);
if (rv == NS_ERROR_FILE_NOT_FOUND ||
rv == NS_ERROR_FILE_TARGET_DOES_NOT_EXIST) {
rv = NS_OK;
}
// Again, no fsync is necessary. If the OS crashes before the file
// removal is flushed, then the Cache will search for stale data on
// startup. This will cause the next Cache access to be a bit slow, but
// it seems appropriate after an OS crash.
return NS_OK;
}
bool
MarkerFileExists(const QuotaInfo& aQuotaInfo)
{
nsCOMPtr<nsIFile> marker;
nsresult rv = GetMarkerFileHandle(aQuotaInfo, getter_AddRefs(marker));
if (NS_WARN_IF(NS_FAILED(rv))) { return false; }
bool exists = false;
rv = marker->Exists(&exists);
if (NS_WARN_IF(NS_FAILED(rv))) { return false; }
return exists;
}
} // namespace cache
} // namespace dom
} // namespace mozilla