Backed out changeset 96d1b7238832 (bug 1308317)

This commit is contained in:
Carsten "Tomcat" Book 2016-10-14 14:58:33 +02:00
parent b474cb6353
commit b6187e2b2e
2 changed files with 209 additions and 64 deletions

View File

@ -6,11 +6,12 @@
#include <stdint.h>
#include <string.h>
#include "nsIObjectInputStream.h"
#include "nsIObjectOutputStream.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/MathAlgorithms.h"
#include "nsSupportsArray.h"
#include "nsSupportsArrayEnumerator.h"
#include "nsIObjectInputStream.h"
#include "nsIObjectOutputStream.h"
nsresult
nsQueryElementAt::operator()(const nsIID& aIID, void** aResult) const
@ -28,11 +29,69 @@ nsQueryElementAt::operator()(const nsIID& aIID, void** aResult) const
nsSupportsArray::nsSupportsArray()
{
mArray = mAutoArray;
mArraySize = kAutoArraySize;
mCount = 0;
}
nsSupportsArray::~nsSupportsArray()
{
Clear();
DeleteArray();
}
bool
nsSupportsArray::GrowArrayBy(uint32_t aGrowBy)
{
const uint32_t kGrowArrayBy = 8;
const uint32_t kLinearThreshold = 16 * sizeof(nsISupports*);
// We have to grow the array. Grow by kGrowArrayBy slots if we're smaller
// than kLinearThreshold bytes, or a power of two if we're larger.
// This is much more efficient with most memory allocators, especially
// if it's very large, or of the allocator is binned.
if (aGrowBy < kGrowArrayBy) {
aGrowBy = kGrowArrayBy;
}
CheckedUint32 newCount(mArraySize);
newCount += aGrowBy; // Minimum increase
CheckedUint32 newSize(sizeof(mArray[0]));
newSize *= newCount;
if (!newSize.isValid()) {
return false;
}
if (newSize.value() >= kLinearThreshold) {
// newCount includes enough space for at least kGrowArrayBy new slots.
// Select the next power-of-two size in bytes above that if newSize is
// not a power of two.
if (newSize.value() & (newSize.value() - 1)) {
newSize = UINT64_C(1) << mozilla::CeilingLog2(newSize.value());
if (!newSize.isValid()) {
return false;
}
}
newCount = newSize / sizeof(mArray[0]);
}
// XXX This would be far more efficient in many allocators if we used
// XXX PR_Realloc(), etc
nsISupports** oldArray = mArray;
mArray = new nsISupports*[newCount.value()];
mArraySize = newCount.value();
if (oldArray) { // need to move old data
if (0 < mCount) {
::memcpy(mArray, oldArray, mCount * sizeof(nsISupports*));
}
if (oldArray != &(mAutoArray[0])) {
delete[] oldArray;
}
}
return true;
}
nsresult
@ -53,8 +112,6 @@ NS_IMPL_ISUPPORTS(nsSupportsArray, nsISupportsArray, nsICollection,
NS_IMETHODIMP
nsSupportsArray::Read(nsIObjectInputStream* aStream)
{
// TODO(ER): This used to leak when resizing the array. Not sure if that was
// intentional, I'm guessing not.
nsresult rv;
uint32_t newArraySize;
@ -63,40 +120,43 @@ nsSupportsArray::Read(nsIObjectInputStream* aStream)
return rv;
}
uint32_t count;
rv = aStream->Read32(&count);
if (newArraySize <= kAutoArraySize) {
if (mArray != mAutoArray) {
delete[] mArray;
mArray = mAutoArray;
}
newArraySize = kAutoArraySize;
} else {
if (newArraySize <= mArraySize) {
// Keep non-default-size mArray, it's more than big enough.
newArraySize = mArraySize;
} else {
nsISupports** array = new nsISupports*[newArraySize];
if (mArray != mAutoArray) {
delete[] mArray;
}
mArray = array;
}
}
mArraySize = newArraySize;
rv = aStream->Read32(&mCount);
if (NS_FAILED(rv)) {
return rv;
}
NS_ASSERTION(count <= newArraySize, "overlarge mCount!");
if (count > newArraySize) {
count = newArraySize;
NS_ASSERTION(mCount <= mArraySize, "overlarge mCount!");
if (mCount > mArraySize) {
mCount = mArraySize;
}
// Don't clear out our array until we know we have enough space for the new
// one and have successfully copied everything out of the stream.
ISupportsArray tmp;
if (!tmp.SetCapacity(newArraySize, mozilla::fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
auto elems = tmp.AppendElements(count, mozilla::fallible);
for (uint32_t i = 0; i < count; i++) {
rv = aStream->ReadObject(true, &elems[i]);
for (uint32_t i = 0; i < mCount; i++) {
rv = aStream->ReadObject(true, &mArray[i]);
if (NS_FAILED(rv)) {
return rv;
}
}
// Now clear out existing refs and replace with the new array.
for (auto& item : mArray) {
NS_IF_RELEASE(item);
}
mArray.Clear();
mArray.SwapElements(tmp);
return NS_OK;
}
@ -105,18 +165,18 @@ nsSupportsArray::Write(nsIObjectOutputStream* aStream)
{
nsresult rv;
rv = aStream->Write32(mArray.Capacity());
rv = aStream->Write32(mArraySize);
if (NS_FAILED(rv)) {
return rv;
}
rv = aStream->Write32(mArray.Length());
rv = aStream->Write32(mCount);
if (NS_FAILED(rv)) {
return rv;
}
for (auto& item : mArray) {
rv = aStream->WriteObject(item, true);
for (uint32_t i = 0; i < mCount; i++) {
rv = aStream->WriteObject(mArray[i], true);
if (NS_FAILED(rv)) {
return rv;
}
@ -125,42 +185,95 @@ nsSupportsArray::Write(nsIObjectOutputStream* aStream)
return NS_OK;
}
void
nsSupportsArray::DeleteArray(void)
{
Clear();
if (mArray != &(mAutoArray[0])) {
delete[] mArray;
mArray = mAutoArray;
mArraySize = kAutoArraySize;
}
}
NS_IMETHODIMP
nsSupportsArray::GetElementAt(uint32_t aIndex, nsISupports** aOutPtr)
{
NS_IF_ADDREF(*aOutPtr = mArray.SafeElementAt(aIndex, nullptr));
*aOutPtr = nullptr;
if (aIndex < mCount) {
NS_IF_ADDREF(*aOutPtr = mArray[aIndex]);
}
return NS_OK;
}
NS_IMETHODIMP_(int32_t)
nsSupportsArray::IndexOf(const nsISupports* aPossibleElement)
{
return mArray.IndexOf(aPossibleElement);
const nsISupports** start = (const nsISupports**)mArray; // work around goofy compiler behavior
const nsISupports** ep = start;
const nsISupports** end = (start + mCount);
while (ep < end) {
if (aPossibleElement == *ep) {
return (ep - start);
}
ep++;
}
return -1;
}
NS_IMETHODIMP_(int32_t)
nsSupportsArray::LastIndexOf(const nsISupports* aPossibleElement)
{
return mArray.LastIndexOf(aPossibleElement);
if (0 < mCount) {
const nsISupports** start = (const nsISupports**)mArray; // work around goofy compiler behavior
const nsISupports** ep = (start + mCount);
while (start <= --ep) {
if (aPossibleElement == *ep) {
return (ep - start);
}
}
}
return -1;
}
NS_IMETHODIMP_(bool)
nsSupportsArray::InsertElementAt(nsISupports* aElement, uint32_t aIndex)
{
if (aIndex <= mCount) {
CheckedUint32 newCount(mCount);
newCount += 1;
if (!newCount.isValid()) {
return false;
}
if (aIndex > mArray.Length() ||
!mArray.InsertElementAt(aIndex, aElement, mozilla::fallible)) {
return false;
if (mArraySize < newCount.value()) {
// need to grow the array
if (!GrowArrayBy(1)) {
return false;
}
}
// Could be slightly more efficient if GrowArrayBy knew about the
// split, but the difference is trivial.
uint32_t slide = (mCount - aIndex);
if (0 < slide) {
::memmove(mArray + aIndex + 1, mArray + aIndex,
slide * sizeof(nsISupports*));
}
mArray[aIndex] = aElement;
NS_IF_ADDREF(aElement);
mCount++;
return true;
}
NS_IF_ADDREF(aElement);
return true;
return false;
}
NS_IMETHODIMP_(bool)
nsSupportsArray::ReplaceElementAt(nsISupports* aElement, uint32_t aIndex)
{
if (aIndex < mArray.Length()) {
if (aIndex < mCount) {
NS_IF_ADDREF(aElement); // addref first in case it's the same object!
NS_IF_RELEASE(mArray[aIndex]);
mArray[aIndex] = aElement;
@ -172,9 +285,15 @@ nsSupportsArray::ReplaceElementAt(nsISupports* aElement, uint32_t aIndex)
NS_IMETHODIMP_(bool)
nsSupportsArray::RemoveElementAt(uint32_t aIndex)
{
if (aIndex + 1 <= mArray.Length()) {
if (aIndex + 1 <= mCount) {
NS_IF_RELEASE(mArray[aIndex]);
mArray.RemoveElementAt(aIndex);
mCount -= 1;
int32_t slide = (mCount - aIndex);
if (0 < slide) {
::memmove(mArray + aIndex, mArray + aIndex + 1,
slide * sizeof(nsISupports*));
}
return true;
}
return false;
@ -194,19 +313,35 @@ nsSupportsArray::RemoveElement(nsISupports* aElement)
NS_IMETHODIMP
nsSupportsArray::Clear(void)
{
for (auto& item : mArray) {
NS_IF_RELEASE(item);
if (0 < mCount) {
do {
--mCount;
NS_IF_RELEASE(mArray[mCount]);
} while (0 != mCount);
}
mArray.Clear();
return NS_OK;
}
NS_IMETHODIMP
nsSupportsArray::Compact(void)
{
mArray.Compact();
if ((mArraySize != mCount) && (kAutoArraySize < mArraySize)) {
nsISupports** oldArray = mArray;
if (mCount <= kAutoArraySize) {
mArray = mAutoArray;
mArraySize = kAutoArraySize;
} else {
mArray = new nsISupports*[mCount];
if (!mArray) {
mArray = oldArray;
return NS_OK;
}
mArraySize = mCount;
}
::memcpy(mArray, oldArray, mCount * sizeof(nsISupports*));
delete[] oldArray;
}
return NS_OK;
}
@ -228,10 +363,10 @@ nsSupportsArray::Clone(nsISupportsArray** aResult)
return rv;
}
for (auto& item : mArray) {
// AppendElement does an odd cast of bool to nsresult, we just cast back
// here.
if (!(bool)newArray->AppendElement(item)) {
uint32_t count = 0;
Count(&count);
for (uint32_t i = 0; i < count; i++) {
if (!newArray->InsertElementAt(mArray[i], i)) {
return NS_ERROR_OUT_OF_MEMORY;
}
}

View File

@ -8,9 +8,10 @@
#define nsSupportsArray_h__
#include "nsISupportsArray.h"
#include "nsTArray.h"
#include "mozilla/Attributes.h"
static const uint32_t kAutoArraySize = 8;
class nsSupportsArray final : public nsISupportsArray
{
~nsSupportsArray(void); // nonvirtual since we're not subclassed
@ -28,16 +29,18 @@ public:
// nsICollection methods:
NS_IMETHOD Count(uint32_t* aResult) override
{
*aResult = mArray.Length();
*aResult = mCount;
return NS_OK;
}
NS_IMETHOD GetElementAt(uint32_t aIndex, nsISupports** aResult) override;
MOZ_MUST_USE NS_IMETHOD
QueryElementAt(uint32_t aIndex, const nsIID& aIID, void** aResult) override
{
nsISupports* element = mArray.SafeElementAt(aIndex, nullptr);
if (element) {
return element->QueryInterface(aIID, aResult);
if (aIndex < mCount) {
nsISupports* element = mArray[aIndex];
if (element) {
return element->QueryInterface(aIID, aResult);
}
}
return NS_ERROR_FAILURE;
}
@ -49,7 +52,7 @@ public:
MOZ_MUST_USE NS_IMETHOD AppendElement(nsISupports* aElement) override
{
// XXX Invalid cast of bool to nsresult (bug 778110)
return (nsresult)InsertElementAt(aElement, mArray.Length())/* ? NS_OK : NS_ERROR_FAILURE*/;
return (nsresult)InsertElementAt(aElement, mCount)/* ? NS_OK : NS_ERROR_FAILURE*/;
}
// XXX this is badly named - should be RemoveFirstElement
MOZ_MUST_USE NS_IMETHOD RemoveElement(nsISupports* aElement) override;
@ -90,12 +93,19 @@ public:
MOZ_MUST_USE NS_IMETHOD Clone(nsISupportsArray** aResult) override;
protected:
void DeleteArray(void);
bool GrowArrayBy(uint32_t aGrowBy);
nsISupports** mArray;
uint32_t mArraySize;
uint32_t mCount;
nsISupports* mAutoArray[kAutoArraySize];
private:
// Copy constructors are not allowed
explicit nsSupportsArray(const nsISupportsArray& aOther);
typedef AutoTArray<nsISupports*, 8> ISupportsArray;
ISupportsArray mArray;
};
#endif // nsSupportsArray_h__