Add m-esr52 at 52.6.0

1 files changed, 622 insertions, 0 deletions

diff --git a/dom/xslt/xpath/txNodeSet.cpp b/dom/xslt/xpath/txNodeSet.cpp
new file mode 100644
index 000000000..a55317e33
--- /dev/null
+++ b/dom/xslt/xpath/txNodeSet.cpp
@@ -0,0 +1,622 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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 "txNodeSet.h"
+#include "txLog.h"
+#include "nsMemory.h"
+#include "txXPathTreeWalker.h"
+#include <algorithm>
+
+/**
+ * Implementation of an XPath nodeset
+ */
+
+#ifdef NS_BUILD_REFCNT_LOGGING
+#define LOG_CHUNK_MOVE(_start, _new_start, _count)            \
+{                                                             \
+    txXPathNode *start = const_cast<txXPathNode*>(_start);    \
+    while (start < _start + _count) {                         \
+        NS_LogDtor(start, "txXPathNode", sizeof(*start));     \
+        ++start;                                              \
+    }                                                         \
+    start = const_cast<txXPathNode*>(_new_start);             \
+    while (start < _new_start + _count) {                     \
+        NS_LogCtor(start, "txXPathNode", sizeof(*start));     \
+        ++start;                                              \
+    }                                                         \
+}
+#else
+#define LOG_CHUNK_MOVE(_start, _new_start, _count)
+#endif
+
+static const int32_t kTxNodeSetMinSize = 4;
+static const int32_t kTxNodeSetGrowFactor = 2;
+
+#define kForward   1
+#define kReversed -1
+
+txNodeSet::txNodeSet(txResultRecycler* aRecycler)
+    : txAExprResult(aRecycler),
+      mStart(nullptr),
+      mEnd(nullptr),
+      mStartBuffer(nullptr),
+      mEndBuffer(nullptr),
+      mDirection(kForward),
+      mMarks(nullptr)
+{
+}
+
+txNodeSet::txNodeSet(const txXPathNode& aNode, txResultRecycler* aRecycler)
+    : txAExprResult(aRecycler),
+      mStart(nullptr),
+      mEnd(nullptr),
+      mStartBuffer(nullptr),
+      mEndBuffer(nullptr),
+      mDirection(kForward),
+      mMarks(nullptr)
+{
+    if (!ensureGrowSize(1)) {
+        return;
+    }
+
+    new(mStart) txXPathNode(aNode);
+    ++mEnd;
+}
+
+txNodeSet::txNodeSet(const txNodeSet& aSource, txResultRecycler* aRecycler)
+    : txAExprResult(aRecycler),
+      mStart(nullptr),
+      mEnd(nullptr),
+      mStartBuffer(nullptr),
+      mEndBuffer(nullptr),
+      mDirection(kForward),
+      mMarks(nullptr)
+{
+    append(aSource);
+}
+
+txNodeSet::~txNodeSet()
+{
+    delete [] mMarks;
+
+    if (mStartBuffer) {
+        destroyElements(mStart, mEnd);
+
+        free(mStartBuffer);
+    }
+}
+
+nsresult txNodeSet::add(const txXPathNode& aNode)
+{
+    NS_ASSERTION(mDirection == kForward,
+                 "only append(aNode) is supported on reversed nodesets");
+
+    if (isEmpty()) {
+        return append(aNode);
+    }
+
+    bool dupe;
+    txXPathNode* pos = findPosition(aNode, mStart, mEnd, dupe);
+
+    if (dupe) {
+        return NS_OK;
+    }
+
+    // save pos, ensureGrowSize messes with the pointers
+    int32_t moveSize = mEnd - pos;
+    int32_t offset = pos - mStart;
+    if (!ensureGrowSize(1)) {
+        return NS_ERROR_OUT_OF_MEMORY;
+    }
+    // set pos to where it was
+    pos = mStart + offset;
+
+    if (moveSize > 0) {
+        LOG_CHUNK_MOVE(pos, pos + 1, moveSize);
+        memmove(pos + 1, pos, moveSize * sizeof(txXPathNode));
+    }
+
+    new(pos) txXPathNode(aNode);
+    ++mEnd;
+
+    return NS_OK;
+}
+
+nsresult txNodeSet::add(const txNodeSet& aNodes)
+{
+    return add(aNodes, copyElements, nullptr);
+}
+
+nsresult txNodeSet::addAndTransfer(txNodeSet* aNodes)
+{
+    // failure is out-of-memory, transfer didn't happen
+    nsresult rv = add(*aNodes, transferElements, destroyElements);
+    NS_ENSURE_SUCCESS(rv, rv);
+
+#ifdef TX_DONT_RECYCLE_BUFFER
+    if (aNodes->mStartBuffer) {
+        free(aNodes->mStartBuffer);
+        aNodes->mStartBuffer = aNodes->mEndBuffer = nullptr;
+    }
+#endif
+    aNodes->mStart = aNodes->mEnd = aNodes->mStartBuffer;
+
+    return NS_OK;
+}
+
+/**
+ * add(aNodeSet, aTransferOp)
+ *
+ * The code is optimized to make a minimum number of calls to
+ * Node::compareDocumentPosition. The idea is this:
+ * We have the two nodesets (number indicate "document position")
+ * 
+ * 1 3 7             <- source 1
+ * 2 3 6 8 9         <- source 2
+ * _ _ _ _ _ _ _ _   <- result
+ * 
+ * 
+ * When merging these nodesets into the result, the nodes are transfered
+ * in chunks to the end of the buffer so that each chunk does not contain
+ * a node from the other nodeset, in document order.
+ *
+ * We select the last non-transfered node in the first nodeset and find
+ * where in the other nodeset it would be inserted. In this case we would
+ * take the 7 from the first nodeset and find the position between the
+ * 6 and 8 in the second. We then take the nodes after the insert-position
+ * and transfer them to the end of the resulting nodeset. Which in this case
+ * means that we first transfered the 8 and 9 nodes, giving us the following:
+ * 
+ * 1 3 7             <- source 1
+ * 2 3 6             <- source 2
+ * _ _ _ _ _ _ 8 9   <- result
+ *
+ * The corresponding procedure is done for the second nodeset, that is
+ * the insertion position of the 6 in the first nodeset is found, which
+ * is between the 3 and the 7. The 7 is memmoved (as it stays within
+ * the same nodeset) to the result buffer.
+ *
+ * As the result buffer is filled from the end, it is safe to share the
+ * buffer between this nodeset and the result.
+ * 
+ * This is repeated until both of the nodesets are empty.
+ *
+ * If we find a duplicate node when searching for where insertposition we
+ * check for sequences of duplicate nodes, which can be optimized.
+ *
+ */
+nsresult txNodeSet::add(const txNodeSet& aNodes, transferOp aTransfer,
+                        destroyOp aDestroy)
+{
+    NS_ASSERTION(mDirection == kForward,
+                 "only append(aNode) is supported on reversed nodesets");
+
+    if (aNodes.isEmpty()) {
+        return NS_OK;
+    }
+
+    if (!ensureGrowSize(aNodes.size())) {
+        return NS_ERROR_OUT_OF_MEMORY;
+    }
+
+    // This is probably a rather common case, so lets try to shortcut.
+    if (mStart == mEnd ||
+        txXPathNodeUtils::comparePosition(mEnd[-1], *aNodes.mStart) < 0) {
+        aTransfer(mEnd, aNodes.mStart, aNodes.mEnd);
+        mEnd += aNodes.size();
+
+        return NS_OK;
+    }
+
+    // Last element in this nodeset
+    txXPathNode* thisPos = mEnd;
+
+    // Last element of the other nodeset
+    txXPathNode* otherPos = aNodes.mEnd;
+
+    // Pointer to the insertion point in this nodeset
+    txXPathNode* insertPos = mEndBuffer;
+
+    bool dupe;
+    txXPathNode* pos;
+    int32_t count;
+    while (thisPos > mStart || otherPos > aNodes.mStart) {
+        // Find where the last remaining node of this nodeset would
+        // be inserted in the other nodeset.
+        if (thisPos > mStart) {
+            pos = findPosition(thisPos[-1], aNodes.mStart, otherPos, dupe);
+
+            if (dupe) {
+                const txXPathNode *deletePos = thisPos;
+                --thisPos; // this is already added
+                // check dupe sequence
+                while (thisPos > mStart && pos > aNodes.mStart &&
+                       thisPos[-1] == pos[-1]) {
+                    --thisPos;
+                    --pos;
+                }
+
+                if (aDestroy) {
+                    aDestroy(thisPos, deletePos);
+                }
+            }
+        }
+        else {
+            pos = aNodes.mStart;
+        }
+
+        // Transfer the otherNodes after the insertion point to the result
+        count = otherPos - pos;
+        if (count > 0) {
+            insertPos -= count;
+            aTransfer(insertPos, pos, otherPos);
+            otherPos -= count;
+        }
+
+        // Find where the last remaining node of the otherNodeset would
+        // be inserted in this nodeset.
+        if (otherPos > aNodes.mStart) {
+            pos = findPosition(otherPos[-1], mStart, thisPos, dupe);
+
+            if (dupe) {
+                const txXPathNode *deletePos = otherPos;
+                --otherPos; // this is already added
+                // check dupe sequence
+                while (otherPos > aNodes.mStart && pos > mStart &&
+                       otherPos[-1] == pos[-1]) {
+                    --otherPos;
+                    --pos;
+                }
+
+                if (aDestroy) {
+                    aDestroy(otherPos, deletePos);
+                }
+            }
+        }
+        else {
+            pos = mStart;
+        }
+
+        // Move the nodes from this nodeset after the insertion point
+        // to the result
+        count = thisPos - pos;
+        if (count > 0) {
+            insertPos -= count;
+            LOG_CHUNK_MOVE(pos, insertPos, count);
+            memmove(insertPos, pos, count * sizeof(txXPathNode));
+            thisPos -= count;
+        }
+    }
+    mStart = insertPos;
+    mEnd = mEndBuffer;
+    
+    return NS_OK;
+}
+
+/**
+ * Append API
+ * These functions should be used with care.
+ * They are intended to be used when the caller assures that the resulting
+ * nodeset remains in document order.
+ * Abuse will break document order, and cause errors in the result.
+ * These functions are significantly faster than the add API, as no
+ * order info operations will be performed.
+ */
+
+nsresult
+txNodeSet::append(const txXPathNode& aNode)
+{
+    if (!ensureGrowSize(1)) {
+        return NS_ERROR_OUT_OF_MEMORY;
+    }
+
+    if (mDirection == kForward) {
+        new(mEnd) txXPathNode(aNode);
+        ++mEnd;
+
+        return NS_OK;
+    }
+
+    new(--mStart) txXPathNode(aNode);
+
+    return NS_OK;
+}
+
+nsresult
+txNodeSet::append(const txNodeSet& aNodes)
+{
+    NS_ASSERTION(mDirection == kForward,
+                 "only append(aNode) is supported on reversed nodesets");
+
+    if (aNodes.isEmpty()) {
+        return NS_OK;
+    }
+
+    int32_t appended = aNodes.size();
+    if (!ensureGrowSize(appended)) {
+        return NS_ERROR_OUT_OF_MEMORY;
+    }
+
+    copyElements(mEnd, aNodes.mStart, aNodes.mEnd);
+    mEnd += appended;
+
+    return NS_OK;
+}
+
+nsresult
+txNodeSet::mark(int32_t aIndex)
+{
+    NS_ASSERTION(aIndex >= 0 && mStart && mEnd - mStart > aIndex,
+                 "index out of bounds");
+    if (!mMarks) {
+        int32_t length = size();
+        mMarks = new bool[length];
+        memset(mMarks, 0, length * sizeof(bool));
+    }
+    if (mDirection == kForward) {
+        mMarks[aIndex] = true;
+    }
+    else {
+        mMarks[size() - aIndex - 1] = true;
+    }
+
+    return NS_OK;
+}
+
+nsresult
+txNodeSet::sweep()
+{
+    if (!mMarks) {
+        // sweep everything
+        clear();
+    }
+
+    int32_t chunk, pos = 0;
+    int32_t length = size();
+    txXPathNode* insertion = mStartBuffer;
+
+    while (pos < length) {
+        while (pos < length && !mMarks[pos]) {
+            // delete unmarked
+            mStart[pos].~txXPathNode();
+            ++pos;
+        }
+        // find chunk to move
+        chunk = 0;
+        while (pos < length && mMarks[pos]) {
+            ++pos;
+            ++chunk;
+        }
+        // move chunk
+        if (chunk > 0) {
+            LOG_CHUNK_MOVE(mStart + pos - chunk, insertion, chunk);
+            memmove(insertion, mStart + pos - chunk,
+                    chunk * sizeof(txXPathNode));
+            insertion += chunk;
+        }
+    }
+    mStart = mStartBuffer;
+    mEnd = insertion;
+    delete [] mMarks;
+    mMarks = nullptr;
+
+    return NS_OK;
+}
+
+void
+txNodeSet::clear()
+{
+    destroyElements(mStart, mEnd);
+#ifdef TX_DONT_RECYCLE_BUFFER
+    if (mStartBuffer) {
+        free(mStartBuffer);
+        mStartBuffer = mEndBuffer = nullptr;
+    }
+#endif
+    mStart = mEnd = mStartBuffer;
+    delete [] mMarks;
+    mMarks = nullptr;
+    mDirection = kForward;
+}
+
+int32_t
+txNodeSet::indexOf(const txXPathNode& aNode, uint32_t aStart) const
+{
+    NS_ASSERTION(mDirection == kForward,
+                 "only append(aNode) is supported on reversed nodesets");
+
+    if (!mStart || mStart == mEnd) {
+        return -1;
+    }
+
+    txXPathNode* pos = mStart + aStart;
+    for (; pos < mEnd; ++pos) {
+        if (*pos == aNode) {
+            return pos - mStart;
+        }
+    }
+
+    return -1;
+}
+
+const txXPathNode&
+txNodeSet::get(int32_t aIndex) const
+{
+    if (mDirection == kForward) {
+        return mStart[aIndex];
+    }
+
+    return mEnd[-aIndex - 1];
+}
+
+short
+txNodeSet::getResultType()
+{
+    return txAExprResult::NODESET;
+}
+
+bool
+txNodeSet::booleanValue()
+{
+    return !isEmpty();
+}
+double
+txNodeSet::numberValue()
+{
+    nsAutoString str;
+    stringValue(str);
+
+    return txDouble::toDouble(str);
+}
+
+void
+txNodeSet::stringValue(nsString& aStr)
+{
+    NS_ASSERTION(mDirection == kForward,
+                 "only append(aNode) is supported on reversed nodesets");
+    if (isEmpty()) {
+        return;
+    }
+    txXPathNodeUtils::appendNodeValue(get(0), aStr);
+}
+
+const nsString*
+txNodeSet::stringValuePointer()
+{
+    return nullptr;
+}
+
+bool txNodeSet::ensureGrowSize(int32_t aSize)
+{
+    // check if there is enough place in the buffer as is
+    if (mDirection == kForward && aSize <= mEndBuffer - mEnd) {
+        return true;
+    }
+
+    if (mDirection == kReversed && aSize <= mStart - mStartBuffer) {
+        return true;
+    }
+
+    // check if we just have to align mStart to have enough space
+    int32_t oldSize = mEnd - mStart;
+    int32_t oldLength = mEndBuffer - mStartBuffer;
+    int32_t ensureSize = oldSize + aSize;
+    if (ensureSize <= oldLength) {
+        // just move the buffer
+        txXPathNode* dest = mStartBuffer;
+        if (mDirection == kReversed) {
+            dest = mEndBuffer - oldSize;
+        }
+        LOG_CHUNK_MOVE(mStart, dest, oldSize);
+        memmove(dest, mStart, oldSize * sizeof(txXPathNode));
+        mStart = dest;
+        mEnd = dest + oldSize;
+            
+        return true;
+    }
+
+    // This isn't 100% safe. But until someone manages to make a 1gig nodeset
+    // it should be ok.
+    int32_t newLength = std::max(oldLength, kTxNodeSetMinSize);
+
+    while (newLength < ensureSize) {
+        newLength *= kTxNodeSetGrowFactor;
+    }
+
+    txXPathNode* newArr = static_cast<txXPathNode*>
+                                     (moz_xmalloc(newLength *
+                                                         sizeof(txXPathNode)));
+    if (!newArr) {
+        return false;
+    }
+
+    txXPathNode* dest = newArr;
+    if (mDirection == kReversed) {
+        dest += newLength - oldSize;
+    }
+
+    if (oldSize > 0) {
+        LOG_CHUNK_MOVE(mStart, dest, oldSize);
+        memcpy(dest, mStart, oldSize * sizeof(txXPathNode));
+    }
+
+    if (mStartBuffer) {
+#ifdef DEBUG
+        memset(mStartBuffer, 0,
+               (mEndBuffer - mStartBuffer) * sizeof(txXPathNode));
+#endif
+        free(mStartBuffer);
+    }
+
+    mStartBuffer = newArr;
+    mEndBuffer = mStartBuffer + newLength;
+    mStart = dest;
+    mEnd = dest + oldSize;
+
+    return true;
+}
+
+txXPathNode*
+txNodeSet::findPosition(const txXPathNode& aNode, txXPathNode* aFirst,
+                        txXPathNode* aLast, bool& aDupe) const
+{
+    aDupe = false;
+    if (aLast - aFirst <= 2) {
+        // If we search 2 nodes or less there is no point in further divides
+        txXPathNode* pos = aFirst;
+        for (; pos < aLast; ++pos) {
+            int cmp = txXPathNodeUtils::comparePosition(aNode, *pos);
+            if (cmp < 0) {
+                return pos;
+            }
+
+            if (cmp == 0) {
+                aDupe = true;
+
+                return pos;
+            }
+        }
+        return pos;
+    }
+
+    // (cannot add two pointers)
+    txXPathNode* midpos = aFirst + (aLast - aFirst) / 2;
+    int cmp = txXPathNodeUtils::comparePosition(aNode, *midpos);
+    if (cmp == 0) {
+        aDupe = true;
+
+        return midpos;
+    }
+
+    if (cmp > 0) {
+        return findPosition(aNode, midpos + 1, aLast, aDupe);
+    }
+
+    // midpos excluded as end of range
+
+    return findPosition(aNode, aFirst, midpos, aDupe);
+}
+
+/* static */
+void
+txNodeSet::copyElements(txXPathNode* aDest,
+                        const txXPathNode* aStart, const txXPathNode* aEnd)
+{
+    const txXPathNode* pos = aStart;
+    while (pos < aEnd) {
+        new(aDest) txXPathNode(*pos);
+        ++aDest;
+        ++pos;
+    }
+}
+
+/* static */
+void
+txNodeSet::transferElements(txXPathNode* aDest,
+                            const txXPathNode* aStart, const txXPathNode* aEnd)
+{
+    LOG_CHUNK_MOVE(aStart, aDest, (aEnd - aStart));
+    memcpy(aDest, aStart, (aEnd - aStart) * sizeof(txXPathNode));
+}