1 files changed, 237 insertions, 261 deletions

diff --git a/libs/binder/CursorWindow.cpp b/libs/binder/CursorWindow.cpp
index b02374f..1b85a71 100644
--- a/libs/binder/CursorWindow.cpp
+++ b/libs/binder/CursorWindow.cpp
@@ -19,8 +19,9 @@
 
 #include <utils/Log.h>
 #include <binder/CursorWindow.h>
-#include <binder/MemoryHeapBase.h>
-#include <binder/MemoryBase.h>
+
+#include <cutils/ashmem.h>
+#include <sys/mman.h>
 
 #include <assert.h>
 #include <string.h>
@@ -28,350 +29,325 @@
 
 namespace android {
 
-CursorWindow::CursorWindow(size_t maxSize) :
-    mMaxSize(maxSize)
-{
+CursorWindow::CursorWindow(const String8& name, int ashmemFd,
+        void* data, size_t size, bool readOnly) :
+        mName(name), mAshmemFd(ashmemFd), mData(data), mSize(size), mReadOnly(readOnly) {
+    mHeader = static_cast<Header*>(mData);
 }
 
-bool CursorWindow::setMemory(const sp<IMemory>& memory)
-{
-    mMemory = memory;
-    mData = (uint8_t *) memory->pointer();
-    if (mData == NULL) {
-        return false;
-    }
-    mHeader = (window_header_t *) mData;
-
-    // Make the window read-only
-    ssize_t size = memory->size();
-    mSize = size;
-    mMaxSize = size;
-    mFreeOffset = size;
-LOG_WINDOW("Created CursorWindow from existing IMemory: mFreeOffset = %d, numRows = %d, numColumns = %d, mSize = %d, mMaxSize = %d, mData = %p", mFreeOffset, mHeader->numRows, mHeader->numColumns, mSize, mMaxSize, mData);
-    return true;
+CursorWindow::~CursorWindow() {
+    ::munmap(mData, mSize);
+    ::close(mAshmemFd);
 }
 
-bool CursorWindow::initBuffer(bool localOnly)
-{
-    //TODO Use a non-memory dealer mmap region for localOnly
-
-    sp<MemoryHeapBase> heap;
-    heap = new MemoryHeapBase(mMaxSize, 0, "CursorWindow");
-    if (heap != NULL) {
-        mMemory = new MemoryBase(heap, 0, mMaxSize);
-        if (mMemory != NULL) {
-            mData = (uint8_t *) mMemory->pointer();
-            if (mData) {
-                mHeader = (window_header_t *) mData;
-                mSize = mMaxSize;
-
-                // Put the window into a clean state
-                clear();
-            LOG_WINDOW("Created CursorWindow with new MemoryDealer: mFreeOffset = %d, mSize = %d, mMaxSize = %d, mData = %p", mFreeOffset, mSize, mMaxSize, mData);
-                return true;                
+status_t CursorWindow::create(const String8& name, size_t size, bool localOnly,
+        CursorWindow** outCursorWindow) {
+    String8 ashmemName("CursorWindow: ");
+    ashmemName.append(name);
+    ashmemName.append(localOnly ? " (local)" : " (remote)");
+
+    status_t result;
+    int ashmemFd = ashmem_create_region(ashmemName.string(), size);
+    if (ashmemFd < 0) {
+        result = -errno;
+    } else {
+        result = ashmem_set_prot_region(ashmemFd, PROT_READ | PROT_WRITE);
+        if (result >= 0) {
+            void* data = ::mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, ashmemFd, 0);
+            if (data == MAP_FAILED) {
+                result = -errno;
+            } else {
+                result = ashmem_set_prot_region(ashmemFd, PROT_READ);
+                if (result >= 0) {
+                    CursorWindow* window = new CursorWindow(name, ashmemFd,
+                            data, size, false /*readOnly*/);
+                    result = window->clear();
+                    if (!result) {
+                        LOG_WINDOW("Created new CursorWindow: freeOffset=%d, "
+                                "numRows=%d, numColumns=%d, mSize=%d, mData=%p",
+                                window->mHeader->freeOffset,
+                                window->mHeader->numRows,
+                                window->mHeader->numColumns,
+                                window->mSize, window->mData);
+                        *outCursorWindow = window;
+                        return OK;
+                    }
+                    delete window;
+                }
             }
-        } 
-        LOGE("CursorWindow heap allocation failed");
-        return false;
+            ::munmap(data, size);
+        }
+        ::close(ashmemFd);
+    }
+    *outCursorWindow = NULL;
+    return result;
+}
+
+status_t CursorWindow::createFromParcel(Parcel* parcel, CursorWindow** outCursorWindow) {
+    String8 name = parcel->readString8();
+
+    status_t result;
+    int ashmemFd = parcel->readFileDescriptor();
+    if (ashmemFd == int(BAD_TYPE)) {
+        result = BAD_TYPE;
     } else {
-        LOGE("failed to create the CursorWindow heap");
-        return false;
+        ssize_t size = ashmem_get_size_region(ashmemFd);
+        if (size < 0) {
+            result = UNKNOWN_ERROR;
+        } else {
+            int dupAshmemFd = ::dup(ashmemFd);
+            if (dupAshmemFd < 0) {
+                result = -errno;
+            } else {
+                void* data = ::mmap(NULL, size, PROT_READ, MAP_SHARED, dupAshmemFd, 0);
+                if (data == MAP_FAILED) {
+                    result = -errno;
+                } else {
+                    CursorWindow* window = new CursorWindow(name, dupAshmemFd,
+                            data, size, true /*readOnly*/);
+                    LOG_WINDOW("Created CursorWindow from parcel: freeOffset=%d, "
+                            "numRows=%d, numColumns=%d, mSize=%d, mData=%p",
+                            window->mHeader->freeOffset,
+                            window->mHeader->numRows,
+                            window->mHeader->numColumns,
+                            window->mSize, window->mData);
+                    *outCursorWindow = window;
+                    return OK;
+                }
+                ::close(dupAshmemFd);
+            }
+        }
     }
+    *outCursorWindow = NULL;
+    return result;
 }
 
-CursorWindow::~CursorWindow()
-{
-    // Everything that matters is a smart pointer
+status_t CursorWindow::writeToParcel(Parcel* parcel) {
+    status_t status = parcel->writeString8(mName);
+    if (!status) {
+        status = parcel->writeDupFileDescriptor(mAshmemFd);
+    }
+    return status;
 }
 
-void CursorWindow::clear()
-{
+status_t CursorWindow::clear() {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
+    }
+
+    mHeader->freeOffset = sizeof(Header) + sizeof(RowSlotChunk);
+    mHeader->firstChunkOffset = sizeof(Header);
     mHeader->numRows = 0;
     mHeader->numColumns = 0;
-    mFreeOffset = sizeof(window_header_t) + ROW_SLOT_CHUNK_SIZE;
-    // Mark the first chunk's next 'pointer' as null
-    *((uint32_t *)(mData + mFreeOffset - sizeof(uint32_t))) = 0;
+
+    RowSlotChunk* firstChunk = static_cast<RowSlotChunk*>(offsetToPtr(mHeader->firstChunkOffset));
+    firstChunk->nextChunkOffset = 0;
+    return OK;
 }
 
-int32_t CursorWindow::freeSpace()
-{
-    int32_t freeSpace = mSize - mFreeOffset;
-    if (freeSpace < 0) {
-        freeSpace = 0;
+status_t CursorWindow::setNumColumns(uint32_t numColumns) {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
+    }
+
+    uint32_t cur = mHeader->numColumns;
+    if ((cur > 0 || mHeader->numRows > 0) && cur != numColumns) {
+        LOGE("Trying to go from %d columns to %d", cur, numColumns);
+        return INVALID_OPERATION;
     }
-    return freeSpace;
+    mHeader->numColumns = numColumns;
+    return OK;
 }
 
-field_slot_t * CursorWindow::allocRow()
-{
+status_t CursorWindow::allocRow() {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
+    }
+
     // Fill in the row slot
-    row_slot_t * rowSlot = allocRowSlot();
+    RowSlot* rowSlot = allocRowSlot();
     if (rowSlot == NULL) {
-        return NULL;
+        return NO_MEMORY;
     }
 
     // Allocate the slots for the field directory
-    size_t fieldDirSize = mHeader->numColumns * sizeof(field_slot_t);
-    uint32_t fieldDirOffset = alloc(fieldDirSize);
+    size_t fieldDirSize = mHeader->numColumns * sizeof(FieldSlot);
+    uint32_t fieldDirOffset = alloc(fieldDirSize, true /*aligned*/);
     if (!fieldDirOffset) {
         mHeader->numRows--;
-        LOG_WINDOW("The row failed, so back out the new row accounting from allocRowSlot %d", mHeader->numRows);
-        return NULL;
+        LOG_WINDOW("The row failed, so back out the new row accounting "
+                "from allocRowSlot %d", mHeader->numRows);
+        return NO_MEMORY;
     }
-    field_slot_t * fieldDir = (field_slot_t *)offsetToPtr(fieldDirOffset);
-    memset(fieldDir, 0x0, fieldDirSize);
+    FieldSlot* fieldDir = static_cast<FieldSlot*>(offsetToPtr(fieldDirOffset));
+    memset(fieldDir, 0, fieldDirSize);
 
-LOG_WINDOW("Allocated row %u, rowSlot is at offset %u, fieldDir is %d bytes at offset %u\n", (mHeader->numRows - 1), ((uint8_t *)rowSlot) - mData, fieldDirSize, fieldDirOffset);
+    LOG_WINDOW("Allocated row %u, rowSlot is at offset %u, fieldDir is %d bytes at offset %u\n",
+            mHeader->numRows - 1, offsetFromPtr(rowSlot), fieldDirSize, fieldDirOffset);
     rowSlot->offset = fieldDirOffset;
+    return OK;
+}
+
+status_t CursorWindow::freeLastRow() {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
+    }
 
-    return fieldDir;
+    if (mHeader->numRows > 0) {
+        mHeader->numRows--;
+    }
+    return OK;
 }
 
-uint32_t CursorWindow::alloc(size_t requestedSize, bool aligned)
-{
-    int32_t size;
+uint32_t CursorWindow::alloc(size_t size, bool aligned) {
     uint32_t padding;
     if (aligned) {
         // 4 byte alignment
-        padding = 4 - (mFreeOffset & 0x3);
+        padding = (~mHeader->freeOffset + 1) & 3;
     } else {
         padding = 0;
     }
 
-    size = requestedSize + padding;
-
-    if (size > freeSpace()) {
-        LOGV("need to grow: mSize = %d, size = %d, freeSpace() = %d, numRows = %d", mSize, size,
-                freeSpace(), mHeader->numRows);
-        // Only grow the window if the first row doesn't fit
-        if (mHeader->numRows > 1) {
-            LOGV("not growing since there are already %d row(s), max size %d", mHeader->numRows,
-                    mMaxSize);
-            return 0;
-        }
-
-        // Find a new size that will fit the allocation
-        int allocated = mSize - freeSpace();
-        int newSize = mSize + WINDOW_ALLOCATION_SIZE;
-        while (size > (newSize - allocated)) {
-            newSize += WINDOW_ALLOCATION_SIZE;
-            if (newSize > mMaxSize) {
-                LOGE("Attempting to grow window beyond max size (%d)", mMaxSize);
-                return 0;
-            }
-        }
-LOG_WINDOW("found size %d", newSize);
-        mSize = newSize;
+    uint32_t offset = mHeader->freeOffset + padding;
+    uint32_t nextFreeOffset = offset + size;
+    if (nextFreeOffset > mSize) {
+        LOGE("Window is full: requested allocation %d bytes, "
+                "free space %d bytes, window size %d bytes",
+                size, freeSpace(), mSize);
+        return 0;
     }
 
-    uint32_t offset = mFreeOffset + padding;
-    mFreeOffset += size;
+    mHeader->freeOffset = nextFreeOffset;
     return offset;
 }
 
-row_slot_t * CursorWindow::getRowSlot(int row)
-{
-    LOG_WINDOW("enter getRowSlot current row num %d, this row %d", mHeader->numRows, row);
-    int chunkNum = row / ROW_SLOT_CHUNK_NUM_ROWS;
-    int chunkPos = row % ROW_SLOT_CHUNK_NUM_ROWS;
-    int chunkPtrOffset = sizeof(window_header_t) + ROW_SLOT_CHUNK_SIZE - sizeof(uint32_t);
-    uint8_t * rowChunk = mData + sizeof(window_header_t);
-    for (int i = 0; i < chunkNum; i++) {
-        rowChunk = offsetToPtr(*((uint32_t *)(mData + chunkPtrOffset)));
-        chunkPtrOffset = rowChunk - mData + (ROW_SLOT_CHUNK_NUM_ROWS * sizeof(row_slot_t));
+CursorWindow::RowSlot* CursorWindow::getRowSlot(uint32_t row) {
+    uint32_t chunkPos = row;
+    RowSlotChunk* chunk = static_cast<RowSlotChunk*>(
+            offsetToPtr(mHeader->firstChunkOffset));
+    while (chunkPos >= ROW_SLOT_CHUNK_NUM_ROWS) {
+        chunk = static_cast<RowSlotChunk*>(offsetToPtr(chunk->nextChunkOffset));
+        chunkPos -= ROW_SLOT_CHUNK_NUM_ROWS;
     }
-    return (row_slot_t *)(rowChunk + (chunkPos * sizeof(row_slot_t)));
-    LOG_WINDOW("exit getRowSlot current row num %d, this row %d", mHeader->numRows, row);    
+    return &chunk->slots[chunkPos];
 }
 
-row_slot_t * CursorWindow::allocRowSlot()
-{
-    int chunkNum = mHeader->numRows / ROW_SLOT_CHUNK_NUM_ROWS;
-    int chunkPos = mHeader->numRows % ROW_SLOT_CHUNK_NUM_ROWS;
-    int chunkPtrOffset = sizeof(window_header_t) + ROW_SLOT_CHUNK_SIZE - sizeof(uint32_t);
-    uint8_t * rowChunk = mData + sizeof(window_header_t);
-LOG_WINDOW("Allocating row slot, mHeader->numRows is %d, chunkNum is %d, chunkPos is %d", mHeader->numRows, chunkNum, chunkPos);
-    for (int i = 0; i < chunkNum; i++) {
-        uint32_t nextChunkOffset = *((uint32_t *)(mData + chunkPtrOffset));
-LOG_WINDOW("nextChunkOffset is %d", nextChunkOffset);
-        if (nextChunkOffset == 0) {
-            // Allocate a new row chunk
-            nextChunkOffset = alloc(ROW_SLOT_CHUNK_SIZE, true);
-            if (nextChunkOffset == 0) {
+CursorWindow::RowSlot* CursorWindow::allocRowSlot() {
+    uint32_t chunkPos = mHeader->numRows;
+    RowSlotChunk* chunk = static_cast<RowSlotChunk*>(
+            offsetToPtr(mHeader->firstChunkOffset));
+    while (chunkPos > ROW_SLOT_CHUNK_NUM_ROWS) {
+        chunk = static_cast<RowSlotChunk*>(offsetToPtr(chunk->nextChunkOffset));
+        chunkPos -= ROW_SLOT_CHUNK_NUM_ROWS;
+    }
+    if (chunkPos == ROW_SLOT_CHUNK_NUM_ROWS) {
+        if (!chunk->nextChunkOffset) {
+            chunk->nextChunkOffset = alloc(sizeof(RowSlotChunk), true /*aligned*/);
+            if (!chunk->nextChunkOffset) {
                 return NULL;
             }
-            rowChunk = offsetToPtr(nextChunkOffset);
-LOG_WINDOW("allocated new chunk at %d, rowChunk = %p", nextChunkOffset, rowChunk);
-            *((uint32_t *)(mData + chunkPtrOffset)) = rowChunk - mData;
-            // Mark the new chunk's next 'pointer' as null
-            *((uint32_t *)(rowChunk + ROW_SLOT_CHUNK_SIZE - sizeof(uint32_t))) = 0;
-        } else {
-LOG_WINDOW("follwing 'pointer' to next chunk, offset of next pointer is %d", chunkPtrOffset);
-            rowChunk = offsetToPtr(nextChunkOffset);
-            chunkPtrOffset = rowChunk - mData + (ROW_SLOT_CHUNK_NUM_ROWS * sizeof(row_slot_t));
         }
+        chunk = static_cast<RowSlotChunk*>(offsetToPtr(chunk->nextChunkOffset));
+        chunk->nextChunkOffset = 0;
+        chunkPos = 0;
     }
-    mHeader->numRows++;
-
-    return (row_slot_t *)(rowChunk + (chunkPos * sizeof(row_slot_t)));
-}
-
-field_slot_t * CursorWindow::getFieldSlotWithCheck(int row, int column)
-{
-  if (row < 0 || row >= mHeader->numRows || column < 0 || column >= mHeader->numColumns) {
-      LOGE("Failed to read row# %d, column# from a CursorWindow which has %d rows, %d columns.",
-              row, column, mHeader->numRows, mHeader->numColumns);
-      return NULL;
-  }        
-  row_slot_t * rowSlot = getRowSlot(row);
-  if (!rowSlot) {
-      LOGE("Failed to find rowSlot for row %d", row);
-      return NULL;
-  }
-  if (rowSlot->offset == 0 || rowSlot->offset >= mSize) {
-      LOGE("Invalid rowSlot, offset = %d", rowSlot->offset);
-      return NULL;
-  }  
-  int fieldDirOffset = rowSlot->offset;
-  return ((field_slot_t *)offsetToPtr(fieldDirOffset)) + column;  
+    mHeader->numRows += 1;
+    return &chunk->slots[chunkPos];
 }
 
-void CursorWindow::copyIn(uint32_t offset, uint8_t const * data, size_t size)
-{
-    assert(offset + size <= mSize);    
-    memcpy(mData + offset, data, size);
-}
-
-void CursorWindow::copyIn(uint32_t offset, int64_t data)
-{
-    assert(offset + sizeof(int64_t) <= mSize);
-    memcpy(mData + offset, (uint8_t *)&data, sizeof(int64_t));
-}
-
-void CursorWindow::copyIn(uint32_t offset, double data)
-{
-    assert(offset + sizeof(double) <= mSize);
-    memcpy(mData + offset, (uint8_t *)&data, sizeof(double));
+CursorWindow::FieldSlot* CursorWindow::getFieldSlot(uint32_t row, uint32_t column) {
+    if (row >= mHeader->numRows || column >= mHeader->numColumns) {
+        LOGE("Failed to read row %d, column %d from a CursorWindow which "
+                "has %d rows, %d columns.",
+                row, column, mHeader->numRows, mHeader->numColumns);
+        return NULL;
+    }
+    RowSlot* rowSlot = getRowSlot(row);
+    if (!rowSlot) {
+        LOGE("Failed to find rowSlot for row %d.", row);
+        return NULL;
+    }
+    FieldSlot* fieldDir = static_cast<FieldSlot*>(offsetToPtr(rowSlot->offset));
+    return &fieldDir[column];
 }
 
-void CursorWindow::copyOut(uint32_t offset, uint8_t * data, size_t size)
-{
-    assert(offset + size <= mSize);
-    memcpy(data, mData + offset, size);
+status_t CursorWindow::putBlob(uint32_t row, uint32_t column, const void* value, size_t size) {
+    return putBlobOrString(row, column, value, size, FIELD_TYPE_BLOB);
 }
 
-int64_t CursorWindow::copyOutLong(uint32_t offset)
-{
-    int64_t value;
-    assert(offset + sizeof(int64_t) <= mSize);
-    memcpy(&value, mData + offset, sizeof(int64_t));
-    return value;
+status_t CursorWindow::putString(uint32_t row, uint32_t column, const char* value,
+        size_t sizeIncludingNull) {
+    return putBlobOrString(row, column, value, sizeIncludingNull, FIELD_TYPE_STRING);
 }
 
-double CursorWindow::copyOutDouble(uint32_t offset)
-{
-    double value;
-    assert(offset + sizeof(double) <= mSize);
-    memcpy(&value, mData + offset, sizeof(double));
-    return value;
-}
+status_t CursorWindow::putBlobOrString(uint32_t row, uint32_t column,
+        const void* value, size_t size, int32_t type) {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
+    }
 
-bool CursorWindow::putLong(unsigned int row, unsigned int col, int64_t value)
-{
-    field_slot_t * fieldSlot = getFieldSlotWithCheck(row, col);
+    FieldSlot* fieldSlot = getFieldSlot(row, column);
     if (!fieldSlot) {
-        return false;
+        return BAD_VALUE;
     }
 
-#if WINDOW_STORAGE_INLINE_NUMERICS
-    fieldSlot->data.l = value;
-#else
-    int offset = alloc(sizeof(int64_t));
+    uint32_t offset = alloc(size);
     if (!offset) {
-        return false;
+        return NO_MEMORY;
     }
 
-    copyIn(offset, value);
+    memcpy(offsetToPtr(offset), value, size);
 
+    fieldSlot->type = type;
     fieldSlot->data.buffer.offset = offset;
-    fieldSlot->data.buffer.size = sizeof(int64_t);
-#endif
-    fieldSlot->type = FIELD_TYPE_INTEGER;
-    return true;
+    fieldSlot->data.buffer.size = size;
+    return OK;
 }
 
-bool CursorWindow::putDouble(unsigned int row, unsigned int col, double value)
-{
-    field_slot_t * fieldSlot = getFieldSlotWithCheck(row, col);
-    if (!fieldSlot) {
-        return false;
+status_t CursorWindow::putLong(uint32_t row, uint32_t column, int64_t value) {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
     }
 
-#if WINDOW_STORAGE_INLINE_NUMERICS
-    fieldSlot->data.d = value;
-#else
-    int offset = alloc(sizeof(int64_t));
-    if (!offset) {
-        return false;
+    FieldSlot* fieldSlot = getFieldSlot(row, column);
+    if (!fieldSlot) {
+        return BAD_VALUE;
     }
 
-    copyIn(offset, value);
-
-    fieldSlot->data.buffer.offset = offset;
-    fieldSlot->data.buffer.size = sizeof(double);
-#endif
-    fieldSlot->type = FIELD_TYPE_FLOAT;
-    return true;
+    fieldSlot->type = FIELD_TYPE_INTEGER;
+    fieldSlot->data.l = value;
+    return OK;
 }
 
-bool CursorWindow::putNull(unsigned int row, unsigned int col)
-{
-    field_slot_t * fieldSlot = getFieldSlotWithCheck(row, col);
-    if (!fieldSlot) {
-        return false;
+status_t CursorWindow::putDouble(uint32_t row, uint32_t column, double value) {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
     }
 
-    fieldSlot->type = FIELD_TYPE_NULL;
-    fieldSlot->data.buffer.offset = 0;
-    fieldSlot->data.buffer.size = 0;
-    return true;
-}
-
-bool CursorWindow::getLong(unsigned int row, unsigned int col, int64_t * valueOut)
-{
-    field_slot_t * fieldSlot = getFieldSlotWithCheck(row, col);
-    if (!fieldSlot || fieldSlot->type != FIELD_TYPE_INTEGER) {
-        return false;
+    FieldSlot* fieldSlot = getFieldSlot(row, column);
+    if (!fieldSlot) {
+        return BAD_VALUE;
     }
 
-    *valueOut = getFieldSlotValueLong(fieldSlot);
-    return true;
+    fieldSlot->type = FIELD_TYPE_FLOAT;
+    fieldSlot->data.d = value;
+    return OK;
 }
 
-bool CursorWindow::getDouble(unsigned int row, unsigned int col, double * valueOut)
-{
-    field_slot_t * fieldSlot = getFieldSlotWithCheck(row, col);
-    if (!fieldSlot || fieldSlot->type != FIELD_TYPE_FLOAT) {
-        return false;
+status_t CursorWindow::putNull(uint32_t row, uint32_t column) {
+    if (mReadOnly) {
+        return INVALID_OPERATION;
     }
 
-    *valueOut = getFieldSlotValueDouble(fieldSlot);
-    return true;
-}
-
-bool CursorWindow::getNull(unsigned int row, unsigned int col, bool * valueOut)
-{
-    field_slot_t * fieldSlot = getFieldSlotWithCheck(row, col);
+    FieldSlot* fieldSlot = getFieldSlot(row, column);
     if (!fieldSlot) {
-        return false;
-    }
-    
-    if (fieldSlot->type != FIELD_TYPE_NULL) {
-        *valueOut = false;
-    } else {
-        *valueOut = true;
+        return BAD_VALUE;
     }
-    return true;
+
+    fieldSlot->type = FIELD_TYPE_NULL;
+    fieldSlot->data.buffer.offset = 0;
+    fieldSlot->data.buffer.size = 0;
+    return OK;
 }
 
 }; // namespace android