gecko/storage/TelemetryVFS.cpp
2015-05-19 10:47:33 -07:00

893 lines
25 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :
* 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 <string.h>
#include "mozilla/Telemetry.h"
#include "mozilla/Preferences.h"
#include "sqlite3.h"
#include "nsThreadUtils.h"
#include "mozilla/dom/quota/PersistenceType.h"
#include "mozilla/dom/quota/QuotaManager.h"
#include "mozilla/dom/quota/QuotaObject.h"
#include "mozilla/IOInterposer.h"
// The last VFS version for which this file has been updated.
#define LAST_KNOWN_VFS_VERSION 3
// The last io_methods version for which this file has been updated.
#define LAST_KNOWN_IOMETHODS_VERSION 3
/**
* This preference is a workaround to allow users/sysadmins to identify
* that the profile exists on an NFS share whose implementation
* is incompatible with SQLite's default locking implementation.
* Bug 433129 attempted to automatically identify such file-systems,
* but a reliable way was not found and it was determined that the fallback
* locking is slower than POSIX locking, so we do not want to do it by default.
*/
#define PREF_NFS_FILESYSTEM "storage.nfs_filesystem"
namespace {
using namespace mozilla;
using namespace mozilla::dom::quota;
struct Histograms {
const char *name;
const Telemetry::ID readB;
const Telemetry::ID writeB;
const Telemetry::ID readMS;
const Telemetry::ID writeMS;
const Telemetry::ID syncMS;
};
#define SQLITE_TELEMETRY(FILENAME, HGRAM) \
{ FILENAME, \
Telemetry::MOZ_SQLITE_ ## HGRAM ## _READ_B, \
Telemetry::MOZ_SQLITE_ ## HGRAM ## _WRITE_B, \
Telemetry::MOZ_SQLITE_ ## HGRAM ## _READ_MS, \
Telemetry::MOZ_SQLITE_ ## HGRAM ## _WRITE_MS, \
Telemetry::MOZ_SQLITE_ ## HGRAM ## _SYNC_MS \
}
Histograms gHistograms[] = {
SQLITE_TELEMETRY("places.sqlite", PLACES),
SQLITE_TELEMETRY("cookies.sqlite", COOKIES),
SQLITE_TELEMETRY("webappsstore.sqlite", WEBAPPS),
SQLITE_TELEMETRY(nullptr, OTHER)
};
#undef SQLITE_TELEMETRY
/** RAII class for measuring how long io takes on/off main thread
*/
class IOThreadAutoTimer {
public:
/**
* IOThreadAutoTimer measures time spent in IO. Additionally it
* automatically determines whether IO is happening on the main
* thread and picks an appropriate histogram.
*
* @param id takes a telemetry histogram id. The id+1 must be an
* equivalent histogram for the main thread. Eg, MOZ_SQLITE_OPEN_MS
* is followed by MOZ_SQLITE_OPEN_MAIN_THREAD_MS.
*
* @param aOp optionally takes an IO operation to report through the
* IOInterposer. Filename will be reported as NULL, and reference will be
* either "sqlite-mainthread" or "sqlite-otherthread".
*/
explicit IOThreadAutoTimer(Telemetry::ID id,
IOInterposeObserver::Operation aOp = IOInterposeObserver::OpNone)
: start(TimeStamp::Now()),
id(id),
op(aOp)
{
}
/**
* This constructor is for when we want to report an operation to
* IOInterposer but do not require a telemetry probe.
*
* @param aOp IO Operation to report through the IOInterposer.
*/
explicit IOThreadAutoTimer(IOInterposeObserver::Operation aOp)
: start(TimeStamp::Now()),
id(Telemetry::HistogramCount),
op(aOp)
{
}
~IOThreadAutoTimer()
{
TimeStamp end(TimeStamp::Now());
uint32_t mainThread = NS_IsMainThread() ? 1 : 0;
if (id != Telemetry::HistogramCount) {
Telemetry::AccumulateTimeDelta(static_cast<Telemetry::ID>(id + mainThread),
start, end);
}
// We don't report SQLite I/O on Windows because we have a comprehensive
// mechanism for intercepting I/O on that platform that captures a superset
// of the data captured here.
#if defined(MOZ_ENABLE_PROFILER_SPS) && !defined(XP_WIN)
if (IOInterposer::IsObservedOperation(op)) {
const char* main_ref = "sqlite-mainthread";
const char* other_ref = "sqlite-otherthread";
// Create observation
IOInterposeObserver::Observation ob(op, start, end,
(mainThread ? main_ref : other_ref));
// Report observation
IOInterposer::Report(ob);
}
#endif /* defined(MOZ_ENABLE_PROFILER_SPS) && !defined(XP_WIN) */
}
private:
const TimeStamp start;
const Telemetry::ID id;
IOInterposeObserver::Operation op;
};
struct telemetry_file {
// Base class. Must be first
sqlite3_file base;
// histograms pertaining to this file
Histograms *histograms;
// quota object for this file
nsRefPtr<QuotaObject> quotaObject;
// The chunk size for this file. See the documentation for
// sqlite3_file_control() and FCNTL_CHUNK_SIZE.
int fileChunkSize;
// This contains the vfs that actually does work
sqlite3_file pReal[1];
};
const char*
DatabasePathFromWALPath(const char *zWALName)
{
/**
* Do some sketchy pointer arithmetic to find the parameter key. The WAL
* filename is in the middle of a big allocated block that contains:
*
* - Random Values
* - Main Database Path
* - \0
* - Multiple URI components consisting of:
* - Key
* - \0
* - Value
* - \0
* - \0
* - Journal Path
* - \0
* - WAL Path (zWALName)
* - \0
*
* Because the main database path is preceded by a random value we have to be
* careful when trying to figure out when we should terminate this loop.
*/
MOZ_ASSERT(zWALName);
nsDependentCSubstring dbPath(zWALName, strlen(zWALName));
// Chop off the "-wal" suffix.
NS_NAMED_LITERAL_CSTRING(kWALSuffix, "-wal");
MOZ_ASSERT(StringEndsWith(dbPath, kWALSuffix));
dbPath.Rebind(zWALName, dbPath.Length() - kWALSuffix.Length());
MOZ_ASSERT(!dbPath.IsEmpty());
// We want to scan to the end of the key/value URI pairs. Skip the preceding
// null and go to the last char of the journal path.
const char* cursor = zWALName - 2;
// Make sure we just skipped a null.
MOZ_ASSERT(!*(cursor + 1));
// Walk backwards over the journal path.
while (*cursor) {
cursor--;
}
// There should be another null here.
cursor--;
MOZ_ASSERT(!*cursor);
// Back up one more char to the last char of the previous string. It may be
// the database path or it may be a key/value URI pair.
cursor--;
#ifdef DEBUG
{
// Verify that we just walked over the journal path. Account for the two
// nulls we just skipped.
const char *journalStart = cursor + 3;
nsDependentCSubstring journalPath(journalStart,
strlen(journalStart));
// Chop off the "-journal" suffix.
NS_NAMED_LITERAL_CSTRING(kJournalSuffix, "-journal");
MOZ_ASSERT(StringEndsWith(journalPath, kJournalSuffix));
journalPath.Rebind(journalStart,
journalPath.Length() - kJournalSuffix.Length());
MOZ_ASSERT(!journalPath.IsEmpty());
// Make sure that the database name is a substring of the journal name.
MOZ_ASSERT(journalPath == dbPath);
}
#endif
// Now we're either at the end of the key/value URI pairs or we're at the
// end of the database path. Carefully walk backwards one character at a
// time to do this safely without running past the beginning of the database
// path.
const char *const dbPathStart = dbPath.BeginReading();
const char *dbPathCursor = dbPath.EndReading() - 1;
bool isDBPath = true;
while (true) {
MOZ_ASSERT(*dbPathCursor, "dbPathCursor should never see a null char!");
if (isDBPath) {
isDBPath = dbPathStart <= dbPathCursor &&
*dbPathCursor == *cursor &&
*cursor;
}
if (!isDBPath) {
// This isn't the database path so it must be a value. Scan past it and
// the key also.
for (size_t stringCount = 0; stringCount < 2; stringCount++) {
// Scan past the string to the preceding null character.
while (*cursor) {
cursor--;
}
// Back up one more char to the last char of preceding string.
cursor--;
}
// Reset and start again.
dbPathCursor = dbPath.EndReading() - 1;
isDBPath = true;
continue;
}
MOZ_ASSERT(isDBPath);
MOZ_ASSERT(*cursor);
if (dbPathStart == dbPathCursor) {
// Found the full database path, we're all done.
MOZ_ASSERT(nsDependentCString(cursor) == dbPath);
return cursor;
}
// Change the cursors and go through the loop again.
cursor--;
dbPathCursor--;
}
MOZ_CRASH("Should never get here!");
}
already_AddRefed<QuotaObject>
GetQuotaObjectFromNameAndParameters(const char *zName,
const char *zURIParameterKey)
{
MOZ_ASSERT(zName);
MOZ_ASSERT(zURIParameterKey);
const char *persistenceType =
sqlite3_uri_parameter(zURIParameterKey, "persistenceType");
if (!persistenceType) {
return nullptr;
}
const char *group = sqlite3_uri_parameter(zURIParameterKey, "group");
if (!group) {
NS_WARNING("SQLite URI had 'persistenceType' but not 'group'?!");
return nullptr;
}
const char *origin = sqlite3_uri_parameter(zURIParameterKey, "origin");
if (!origin) {
NS_WARNING("SQLite URI had 'persistenceType' and 'group' but not "
"'origin'?!");
return nullptr;
}
QuotaManager *quotaManager = QuotaManager::Get();
MOZ_ASSERT(quotaManager);
return quotaManager->GetQuotaObject(
PersistenceTypeFromText(nsDependentCString(persistenceType)),
nsDependentCString(group),
nsDependentCString(origin),
NS_ConvertUTF8toUTF16(zName));
}
void
MaybeEstablishQuotaControl(const char *zName,
telemetry_file *pFile,
int flags)
{
MOZ_ASSERT(pFile);
MOZ_ASSERT(!pFile->quotaObject);
if (!(flags & (SQLITE_OPEN_URI | SQLITE_OPEN_WAL))) {
return;
}
MOZ_ASSERT(zName);
const char *zURIParameterKey = (flags & SQLITE_OPEN_WAL) ?
DatabasePathFromWALPath(zName) :
zName;
MOZ_ASSERT(zURIParameterKey);
pFile->quotaObject =
GetQuotaObjectFromNameAndParameters(zName, zURIParameterKey);
}
/*
** Close a telemetry_file.
*/
int
xClose(sqlite3_file *pFile)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc;
{ // Scope for IOThreadAutoTimer
IOThreadAutoTimer ioTimer(IOInterposeObserver::OpClose);
rc = p->pReal->pMethods->xClose(p->pReal);
}
if( rc==SQLITE_OK ){
delete p->base.pMethods;
p->base.pMethods = nullptr;
p->quotaObject = nullptr;
#ifdef DEBUG
p->fileChunkSize = 0;
#endif
}
return rc;
}
/*
** Read data from a telemetry_file.
*/
int
xRead(sqlite3_file *pFile, void *zBuf, int iAmt, sqlite_int64 iOfst)
{
telemetry_file *p = (telemetry_file *)pFile;
IOThreadAutoTimer ioTimer(p->histograms->readMS, IOInterposeObserver::OpRead);
int rc;
rc = p->pReal->pMethods->xRead(p->pReal, zBuf, iAmt, iOfst);
// sqlite likes to read from empty files, this is normal, ignore it.
if (rc != SQLITE_IOERR_SHORT_READ)
Telemetry::Accumulate(p->histograms->readB, rc == SQLITE_OK ? iAmt : 0);
return rc;
}
/*
** Return the current file-size of a telemetry_file.
*/
int
xFileSize(sqlite3_file *pFile, sqlite_int64 *pSize)
{
IOThreadAutoTimer ioTimer(IOInterposeObserver::OpStat);
telemetry_file *p = (telemetry_file *)pFile;
int rc;
rc = p->pReal->pMethods->xFileSize(p->pReal, pSize);
return rc;
}
/*
** Write data to a telemetry_file.
*/
int
xWrite(sqlite3_file *pFile, const void *zBuf, int iAmt, sqlite_int64 iOfst)
{
telemetry_file *p = (telemetry_file *)pFile;
IOThreadAutoTimer ioTimer(p->histograms->writeMS, IOInterposeObserver::OpWrite);
int rc;
if (p->quotaObject) {
MOZ_ASSERT(INT64_MAX - iOfst >= iAmt);
if (!p->quotaObject->MaybeUpdateSize(iOfst + iAmt, /* aTruncate */ false)) {
return SQLITE_FULL;
}
}
rc = p->pReal->pMethods->xWrite(p->pReal, zBuf, iAmt, iOfst);
Telemetry::Accumulate(p->histograms->writeB, rc == SQLITE_OK ? iAmt : 0);
if (p->quotaObject && rc != SQLITE_OK) {
NS_WARNING("xWrite failed on a quota-controlled file, attempting to "
"update its current size...");
sqlite_int64 currentSize;
if (xFileSize(pFile, &currentSize) == SQLITE_OK) {
p->quotaObject->MaybeUpdateSize(currentSize, /* aTruncate */ true);
}
}
return rc;
}
/*
** Truncate a telemetry_file.
*/
int
xTruncate(sqlite3_file *pFile, sqlite_int64 size)
{
IOThreadAutoTimer ioTimer(Telemetry::MOZ_SQLITE_TRUNCATE_MS);
telemetry_file *p = (telemetry_file *)pFile;
int rc;
Telemetry::AutoTimer<Telemetry::MOZ_SQLITE_TRUNCATE_MS> timer;
if (p->quotaObject) {
if (p->fileChunkSize > 0) {
// Round up to the smallest multiple of the chunk size that will hold all
// the data.
size =
((size + p->fileChunkSize - 1) / p->fileChunkSize) * p->fileChunkSize;
}
if (!p->quotaObject->MaybeUpdateSize(size, /* aTruncate */ true)) {
return SQLITE_FULL;
}
}
rc = p->pReal->pMethods->xTruncate(p->pReal, size);
if (p->quotaObject) {
if (rc == SQLITE_OK) {
#ifdef DEBUG
// Make sure xTruncate set the size exactly as we calculated above.
sqlite_int64 newSize;
MOZ_ASSERT(xFileSize(pFile, &newSize) == SQLITE_OK);
MOZ_ASSERT(newSize == size);
#endif
} else {
NS_WARNING("xTruncate failed on a quota-controlled file, attempting to "
"update its current size...");
if (xFileSize(pFile, &size) == SQLITE_OK) {
p->quotaObject->MaybeUpdateSize(size, /* aTruncate */ true);
}
}
}
return rc;
}
/*
** Sync a telemetry_file.
*/
int
xSync(sqlite3_file *pFile, int flags)
{
telemetry_file *p = (telemetry_file *)pFile;
IOThreadAutoTimer ioTimer(p->histograms->syncMS, IOInterposeObserver::OpFSync);
return p->pReal->pMethods->xSync(p->pReal, flags);
}
/*
** Lock a telemetry_file.
*/
int
xLock(sqlite3_file *pFile, int eLock)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc;
rc = p->pReal->pMethods->xLock(p->pReal, eLock);
return rc;
}
/*
** Unlock a telemetry_file.
*/
int
xUnlock(sqlite3_file *pFile, int eLock)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc;
rc = p->pReal->pMethods->xUnlock(p->pReal, eLock);
return rc;
}
/*
** Check if another file-handle holds a RESERVED lock on a telemetry_file.
*/
int
xCheckReservedLock(sqlite3_file *pFile, int *pResOut)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc = p->pReal->pMethods->xCheckReservedLock(p->pReal, pResOut);
return rc;
}
/*
** File control method. For custom operations on a telemetry_file.
*/
int
xFileControl(sqlite3_file *pFile, int op, void *pArg)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc;
// Hook SQLITE_FCNTL_SIZE_HINT for quota-controlled files and do the necessary
// work before passing to the SQLite VFS.
if (op == SQLITE_FCNTL_SIZE_HINT && p->quotaObject) {
sqlite3_int64 hintSize = *static_cast<sqlite3_int64*>(pArg);
sqlite3_int64 currentSize;
rc = xFileSize(pFile, &currentSize);
if (rc != SQLITE_OK) {
return rc;
}
if (hintSize > currentSize) {
rc = xTruncate(pFile, hintSize);
if (rc != SQLITE_OK) {
return rc;
}
}
}
rc = p->pReal->pMethods->xFileControl(p->pReal, op, pArg);
// Grab the file chunk size after the SQLite VFS has approved.
if (op == SQLITE_FCNTL_CHUNK_SIZE && rc == SQLITE_OK) {
p->fileChunkSize = *static_cast<int*>(pArg);
}
#ifdef DEBUG
if (op == SQLITE_FCNTL_SIZE_HINT && p->quotaObject && rc == SQLITE_OK) {
sqlite3_int64 hintSize = *static_cast<sqlite3_int64*>(pArg);
if (p->fileChunkSize > 0) {
hintSize =
((hintSize + p->fileChunkSize - 1) / p->fileChunkSize) *
p->fileChunkSize;
}
sqlite3_int64 currentSize;
MOZ_ASSERT(xFileSize(pFile, &currentSize) == SQLITE_OK);
MOZ_ASSERT(currentSize >= hintSize);
}
#endif
return rc;
}
/*
** Return the sector-size in bytes for a telemetry_file.
*/
int
xSectorSize(sqlite3_file *pFile)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc;
rc = p->pReal->pMethods->xSectorSize(p->pReal);
return rc;
}
/*
** Return the device characteristic flags supported by a telemetry_file.
*/
int
xDeviceCharacteristics(sqlite3_file *pFile)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc;
rc = p->pReal->pMethods->xDeviceCharacteristics(p->pReal);
return rc;
}
/*
** Shared-memory operations.
*/
int
xShmLock(sqlite3_file *pFile, int ofst, int n, int flags)
{
telemetry_file *p = (telemetry_file *)pFile;
return p->pReal->pMethods->xShmLock(p->pReal, ofst, n, flags);
}
int
xShmMap(sqlite3_file *pFile, int iRegion, int szRegion, int isWrite, void volatile **pp)
{
telemetry_file *p = (telemetry_file *)pFile;
int rc;
rc = p->pReal->pMethods->xShmMap(p->pReal, iRegion, szRegion, isWrite, pp);
return rc;
}
void
xShmBarrier(sqlite3_file *pFile){
telemetry_file *p = (telemetry_file *)pFile;
p->pReal->pMethods->xShmBarrier(p->pReal);
}
int
xShmUnmap(sqlite3_file *pFile, int delFlag){
telemetry_file *p = (telemetry_file *)pFile;
int rc;
rc = p->pReal->pMethods->xShmUnmap(p->pReal, delFlag);
return rc;
}
int
xFetch(sqlite3_file *pFile, sqlite3_int64 iOff, int iAmt, void **pp)
{
telemetry_file *p = (telemetry_file *)pFile;
MOZ_ASSERT(p->pReal->pMethods->iVersion >= 3);
return p->pReal->pMethods->xFetch(p->pReal, iOff, iAmt, pp);
}
int
xUnfetch(sqlite3_file *pFile, sqlite3_int64 iOff, void *pResOut)
{
telemetry_file *p = (telemetry_file *)pFile;
MOZ_ASSERT(p->pReal->pMethods->iVersion >= 3);
return p->pReal->pMethods->xUnfetch(p->pReal, iOff, pResOut);
}
int
xOpen(sqlite3_vfs* vfs, const char *zName, sqlite3_file* pFile,
int flags, int *pOutFlags)
{
IOThreadAutoTimer ioTimer(Telemetry::MOZ_SQLITE_OPEN_MS,
IOInterposeObserver::OpCreateOrOpen);
Telemetry::AutoTimer<Telemetry::MOZ_SQLITE_OPEN_MS> timer;
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
int rc;
telemetry_file *p = (telemetry_file *)pFile;
Histograms *h = nullptr;
// check if the filename is one we are probing for
for(size_t i = 0;i < sizeof(gHistograms)/sizeof(gHistograms[0]);i++) {
h = &gHistograms[i];
// last probe is the fallback probe
if (!h->name)
break;
if (!zName)
continue;
const char *match = strstr(zName, h->name);
if (!match)
continue;
char c = match[strlen(h->name)];
// include -wal/-journal too
if (!c || c == '-')
break;
}
p->histograms = h;
MaybeEstablishQuotaControl(zName, p, flags);
rc = orig_vfs->xOpen(orig_vfs, zName, p->pReal, flags, pOutFlags);
if( rc != SQLITE_OK )
return rc;
if( p->pReal->pMethods ){
sqlite3_io_methods *pNew = new sqlite3_io_methods;
const sqlite3_io_methods *pSub = p->pReal->pMethods;
memset(pNew, 0, sizeof(*pNew));
// If the io_methods version is higher than the last known one, you should
// update this VFS adding appropriate IO methods for any methods added in
// the version change.
pNew->iVersion = pSub->iVersion;
MOZ_ASSERT(pNew->iVersion <= LAST_KNOWN_IOMETHODS_VERSION);
pNew->xClose = xClose;
pNew->xRead = xRead;
pNew->xWrite = xWrite;
pNew->xTruncate = xTruncate;
pNew->xSync = xSync;
pNew->xFileSize = xFileSize;
pNew->xLock = xLock;
pNew->xUnlock = xUnlock;
pNew->xCheckReservedLock = xCheckReservedLock;
pNew->xFileControl = xFileControl;
pNew->xSectorSize = xSectorSize;
pNew->xDeviceCharacteristics = xDeviceCharacteristics;
if (pNew->iVersion >= 2) {
// Methods added in version 2.
pNew->xShmMap = pSub->xShmMap ? xShmMap : 0;
pNew->xShmLock = pSub->xShmLock ? xShmLock : 0;
pNew->xShmBarrier = pSub->xShmBarrier ? xShmBarrier : 0;
pNew->xShmUnmap = pSub->xShmUnmap ? xShmUnmap : 0;
}
if (pNew->iVersion >= 3) {
// Methods added in version 3.
// SQLite 3.7.17 calls these methods without checking for nullptr first,
// so we always define them. Verify that we're not going to call
// nullptrs, though.
MOZ_ASSERT(pSub->xFetch);
pNew->xFetch = xFetch;
MOZ_ASSERT(pSub->xUnfetch);
pNew->xUnfetch = xUnfetch;
}
pFile->pMethods = pNew;
}
return rc;
}
int
xDelete(sqlite3_vfs* vfs, const char *zName, int syncDir)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
int rc;
nsRefPtr<QuotaObject> quotaObject;
if (StringEndsWith(nsDependentCString(zName), NS_LITERAL_CSTRING("-wal"))) {
const char *zURIParameterKey = DatabasePathFromWALPath(zName);
MOZ_ASSERT(zURIParameterKey);
quotaObject = GetQuotaObjectFromNameAndParameters(zName, zURIParameterKey);
}
rc = orig_vfs->xDelete(orig_vfs, zName, syncDir);
if (rc == SQLITE_OK && quotaObject) {
MOZ_ALWAYS_TRUE(quotaObject->MaybeUpdateSize(0, /* aTruncate */ true));
}
return rc;
}
int
xAccess(sqlite3_vfs *vfs, const char *zName, int flags, int *pResOut)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xAccess(orig_vfs, zName, flags, pResOut);
}
int
xFullPathname(sqlite3_vfs *vfs, const char *zName, int nOut, char *zOut)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xFullPathname(orig_vfs, zName, nOut, zOut);
}
void*
xDlOpen(sqlite3_vfs *vfs, const char *zFilename)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xDlOpen(orig_vfs, zFilename);
}
void
xDlError(sqlite3_vfs *vfs, int nByte, char *zErrMsg)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
orig_vfs->xDlError(orig_vfs, nByte, zErrMsg);
}
void
(*xDlSym(sqlite3_vfs *vfs, void *pHdle, const char *zSym))(void){
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xDlSym(orig_vfs, pHdle, zSym);
}
void
xDlClose(sqlite3_vfs *vfs, void *pHandle)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
orig_vfs->xDlClose(orig_vfs, pHandle);
}
int
xRandomness(sqlite3_vfs *vfs, int nByte, char *zOut)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xRandomness(orig_vfs, nByte, zOut);
}
int
xSleep(sqlite3_vfs *vfs, int microseconds)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xSleep(orig_vfs, microseconds);
}
int
xCurrentTime(sqlite3_vfs *vfs, double *prNow)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xCurrentTime(orig_vfs, prNow);
}
int
xGetLastError(sqlite3_vfs *vfs, int nBuf, char *zBuf)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xGetLastError(orig_vfs, nBuf, zBuf);
}
int
xCurrentTimeInt64(sqlite3_vfs *vfs, sqlite3_int64 *piNow)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xCurrentTimeInt64(orig_vfs, piNow);
}
static
int
xSetSystemCall(sqlite3_vfs *vfs, const char *zName, sqlite3_syscall_ptr pFunc)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xSetSystemCall(orig_vfs, zName, pFunc);
}
static
sqlite3_syscall_ptr
xGetSystemCall(sqlite3_vfs *vfs, const char *zName)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xGetSystemCall(orig_vfs, zName);
}
static
const char *
xNextSystemCall(sqlite3_vfs *vfs, const char *zName)
{
sqlite3_vfs *orig_vfs = static_cast<sqlite3_vfs*>(vfs->pAppData);
return orig_vfs->xNextSystemCall(orig_vfs, zName);
}
}
namespace mozilla {
namespace storage {
sqlite3_vfs* ConstructTelemetryVFS()
{
#if defined(XP_WIN)
#define EXPECTED_VFS "win32"
#define EXPECTED_VFS_NFS "win32"
#else
#define EXPECTED_VFS "unix"
#define EXPECTED_VFS_NFS "unix-excl"
#endif
bool expected_vfs;
sqlite3_vfs *vfs;
if (Preferences::GetBool(PREF_NFS_FILESYSTEM)) {
vfs = sqlite3_vfs_find(EXPECTED_VFS_NFS);
expected_vfs = (vfs != nullptr);
}
else {
vfs = sqlite3_vfs_find(nullptr);
expected_vfs = vfs->zName && !strcmp(vfs->zName, EXPECTED_VFS);
}
if (!expected_vfs) {
return nullptr;
}
sqlite3_vfs *tvfs = new ::sqlite3_vfs;
memset(tvfs, 0, sizeof(::sqlite3_vfs));
// If the VFS version is higher than the last known one, you should update
// this VFS adding appropriate methods for any methods added in the version
// change.
tvfs->iVersion = vfs->iVersion;
MOZ_ASSERT(vfs->iVersion <= LAST_KNOWN_VFS_VERSION);
tvfs->szOsFile = sizeof(telemetry_file) - sizeof(sqlite3_file) + vfs->szOsFile;
tvfs->mxPathname = vfs->mxPathname;
tvfs->zName = "telemetry-vfs";
tvfs->pAppData = vfs;
tvfs->xOpen = xOpen;
tvfs->xDelete = xDelete;
tvfs->xAccess = xAccess;
tvfs->xFullPathname = xFullPathname;
tvfs->xDlOpen = xDlOpen;
tvfs->xDlError = xDlError;
tvfs->xDlSym = xDlSym;
tvfs->xDlClose = xDlClose;
tvfs->xRandomness = xRandomness;
tvfs->xSleep = xSleep;
tvfs->xCurrentTime = xCurrentTime;
tvfs->xGetLastError = xGetLastError;
if (tvfs->iVersion >= 2) {
// Methods added in version 2.
tvfs->xCurrentTimeInt64 = xCurrentTimeInt64;
}
if (tvfs->iVersion >= 3) {
// Methods added in version 3.
tvfs->xSetSystemCall = xSetSystemCall;
tvfs->xGetSystemCall = xGetSystemCall;
tvfs->xNextSystemCall = xNextSystemCall;
}
return tvfs;
}
}
}