1 /* 2 * Copyright (C) 2006-2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #undef LOG_TAG 18 #define LOG_TAG "CursorWindow" 19 20 #include <androidfw/CursorWindow.h> 21 #include <binder/Parcel.h> 22 #include <utils/Log.h> 23 24 #include <cutils/ashmem.h> 25 #include <sys/mman.h> 26 27 #include <assert.h> 28 #include <string.h> 29 #include <stdlib.h> 30 31 namespace android { 32 33 CursorWindow::CursorWindow(const String8& name, int ashmemFd, 34 void* data, size_t size, bool readOnly) : 35 mName(name), mAshmemFd(ashmemFd), mData(data), mSize(size), mReadOnly(readOnly) { 36 mHeader = static_cast<Header*>(mData); 37 } 38 39 CursorWindow::~CursorWindow() { 40 ::munmap(mData, mSize); 41 ::close(mAshmemFd); 42 } 43 44 status_t CursorWindow::create(const String8& name, size_t size, CursorWindow** outCursorWindow) { 45 String8 ashmemName("CursorWindow: "); 46 ashmemName.append(name); 47 48 status_t result; 49 int ashmemFd = ashmem_create_region(ashmemName.string(), size); 50 if (ashmemFd < 0) { 51 result = -errno; 52 } else { 53 result = ashmem_set_prot_region(ashmemFd, PROT_READ | PROT_WRITE); 54 if (result >= 0) { 55 void* data = ::mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, ashmemFd, 0); 56 if (data == MAP_FAILED) { 57 result = -errno; 58 } else { 59 result = ashmem_set_prot_region(ashmemFd, PROT_READ); 60 if (result >= 0) { 61 CursorWindow* window = new CursorWindow(name, ashmemFd, 62 data, size, false /*readOnly*/); 63 result = window->clear(); 64 if (!result) { 65 LOG_WINDOW("Created new CursorWindow: freeOffset=%d, " 66 "numRows=%d, numColumns=%d, mSize=%d, mData=%p", 67 window->mHeader->freeOffset, 68 window->mHeader->numRows, 69 window->mHeader->numColumns, 70 window->mSize, window->mData); 71 *outCursorWindow = window; 72 return OK; 73 } 74 delete window; 75 } 76 } 77 ::munmap(data, size); 78 } 79 ::close(ashmemFd); 80 } 81 *outCursorWindow = NULL; 82 return result; 83 } 84 85 status_t CursorWindow::createFromParcel(Parcel* parcel, CursorWindow** outCursorWindow) { 86 String8 name = parcel->readString8(); 87 88 status_t result; 89 int ashmemFd = parcel->readFileDescriptor(); 90 if (ashmemFd == int(BAD_TYPE)) { 91 result = BAD_TYPE; 92 } else { 93 ssize_t size = ashmem_get_size_region(ashmemFd); 94 if (size < 0) { 95 result = UNKNOWN_ERROR; 96 } else { 97 int dupAshmemFd = ::dup(ashmemFd); 98 if (dupAshmemFd < 0) { 99 result = -errno; 100 } else { 101 // the size of the ashmem descriptor can be modified between ashmem_get_size_region 102 // call and mmap, so we'll check again immediately after memory is mapped 103 void* data = ::mmap(NULL, size, PROT_READ, MAP_SHARED, dupAshmemFd, 0); 104 if (data == MAP_FAILED) { 105 result = -errno; 106 } else if (ashmem_get_size_region(dupAshmemFd) != size) { 107 ::munmap(data, size); 108 result = BAD_VALUE; 109 } else { 110 CursorWindow* window = new CursorWindow(name, dupAshmemFd, 111 data, size, true /*readOnly*/); 112 LOG_WINDOW("Created CursorWindow from parcel: freeOffset=%d, " 113 "numRows=%d, numColumns=%d, mSize=%d, mData=%p", 114 window->mHeader->freeOffset, 115 window->mHeader->numRows, 116 window->mHeader->numColumns, 117 window->mSize, window->mData); 118 *outCursorWindow = window; 119 return OK; 120 } 121 ::close(dupAshmemFd); 122 } 123 } 124 } 125 *outCursorWindow = NULL; 126 return result; 127 } 128 129 status_t CursorWindow::writeToParcel(Parcel* parcel) { 130 status_t status = parcel->writeString8(mName); 131 if (!status) { 132 status = parcel->writeDupFileDescriptor(mAshmemFd); 133 } 134 return status; 135 } 136 137 status_t CursorWindow::clear() { 138 if (mReadOnly) { 139 return INVALID_OPERATION; 140 } 141 142 mHeader->freeOffset = sizeof(Header) + sizeof(RowSlotChunk); 143 mHeader->firstChunkOffset = sizeof(Header); 144 mHeader->numRows = 0; 145 mHeader->numColumns = 0; 146 147 RowSlotChunk* firstChunk = static_cast<RowSlotChunk*>(offsetToPtr(mHeader->firstChunkOffset)); 148 firstChunk->nextChunkOffset = 0; 149 return OK; 150 } 151 152 status_t CursorWindow::setNumColumns(uint32_t numColumns) { 153 if (mReadOnly) { 154 return INVALID_OPERATION; 155 } 156 157 uint32_t cur = mHeader->numColumns; 158 if ((cur > 0 || mHeader->numRows > 0) && cur != numColumns) { 159 ALOGE("Trying to go from %d columns to %d", cur, numColumns); 160 return INVALID_OPERATION; 161 } 162 mHeader->numColumns = numColumns; 163 return OK; 164 } 165 166 status_t CursorWindow::allocRow() { 167 if (mReadOnly) { 168 return INVALID_OPERATION; 169 } 170 171 // Fill in the row slot 172 RowSlot* rowSlot = allocRowSlot(); 173 if (rowSlot == NULL) { 174 return NO_MEMORY; 175 } 176 177 // Allocate the slots for the field directory 178 size_t fieldDirSize = mHeader->numColumns * sizeof(FieldSlot); 179 uint32_t fieldDirOffset = alloc(fieldDirSize, true /*aligned*/); 180 if (!fieldDirOffset) { 181 mHeader->numRows--; 182 LOG_WINDOW("The row failed, so back out the new row accounting " 183 "from allocRowSlot %d", mHeader->numRows); 184 return NO_MEMORY; 185 } 186 FieldSlot* fieldDir = static_cast<FieldSlot*>(offsetToPtr(fieldDirOffset)); 187 memset(fieldDir, 0, fieldDirSize); 188 189 LOG_WINDOW("Allocated row %u, rowSlot is at offset %u, fieldDir is %d bytes at offset %u\n", 190 mHeader->numRows - 1, offsetFromPtr(rowSlot), fieldDirSize, fieldDirOffset); 191 rowSlot->offset = fieldDirOffset; 192 return OK; 193 } 194 195 status_t CursorWindow::freeLastRow() { 196 if (mReadOnly) { 197 return INVALID_OPERATION; 198 } 199 200 if (mHeader->numRows > 0) { 201 mHeader->numRows--; 202 } 203 return OK; 204 } 205 206 uint32_t CursorWindow::alloc(size_t size, bool aligned) { 207 uint32_t padding; 208 if (aligned) { 209 // 4 byte alignment 210 padding = (~mHeader->freeOffset + 1) & 3; 211 } else { 212 padding = 0; 213 } 214 215 uint32_t offset = mHeader->freeOffset + padding; 216 uint32_t nextFreeOffset = offset + size; 217 if (nextFreeOffset > mSize) { 218 ALOGW("Window is full: requested allocation %zu bytes, " 219 "free space %zu bytes, window size %zu bytes", 220 size, freeSpace(), mSize); 221 return 0; 222 } 223 224 mHeader->freeOffset = nextFreeOffset; 225 return offset; 226 } 227 228 CursorWindow::RowSlot* CursorWindow::getRowSlot(uint32_t row) { 229 uint32_t chunkPos = row; 230 RowSlotChunk* chunk = static_cast<RowSlotChunk*>( 231 offsetToPtr(mHeader->firstChunkOffset)); 232 while (chunkPos >= ROW_SLOT_CHUNK_NUM_ROWS) { 233 chunk = static_cast<RowSlotChunk*>(offsetToPtr(chunk->nextChunkOffset)); 234 chunkPos -= ROW_SLOT_CHUNK_NUM_ROWS; 235 } 236 return &chunk->slots[chunkPos]; 237 } 238 239 CursorWindow::RowSlot* CursorWindow::allocRowSlot() { 240 uint32_t chunkPos = mHeader->numRows; 241 RowSlotChunk* chunk = static_cast<RowSlotChunk*>( 242 offsetToPtr(mHeader->firstChunkOffset)); 243 while (chunkPos > ROW_SLOT_CHUNK_NUM_ROWS) { 244 chunk = static_cast<RowSlotChunk*>(offsetToPtr(chunk->nextChunkOffset)); 245 chunkPos -= ROW_SLOT_CHUNK_NUM_ROWS; 246 } 247 if (chunkPos == ROW_SLOT_CHUNK_NUM_ROWS) { 248 if (!chunk->nextChunkOffset) { 249 chunk->nextChunkOffset = alloc(sizeof(RowSlotChunk), true /*aligned*/); 250 if (!chunk->nextChunkOffset) { 251 return NULL; 252 } 253 } 254 chunk = static_cast<RowSlotChunk*>(offsetToPtr(chunk->nextChunkOffset)); 255 chunk->nextChunkOffset = 0; 256 chunkPos = 0; 257 } 258 mHeader->numRows += 1; 259 return &chunk->slots[chunkPos]; 260 } 261 262 CursorWindow::FieldSlot* CursorWindow::getFieldSlot(uint32_t row, uint32_t column) { 263 if (row >= mHeader->numRows || column >= mHeader->numColumns) { 264 ALOGE("Failed to read row %d, column %d from a CursorWindow which " 265 "has %d rows, %d columns.", 266 row, column, mHeader->numRows, mHeader->numColumns); 267 return NULL; 268 } 269 RowSlot* rowSlot = getRowSlot(row); 270 if (!rowSlot) { 271 ALOGE("Failed to find rowSlot for row %d.", row); 272 return NULL; 273 } 274 FieldSlot* fieldDir = static_cast<FieldSlot*>(offsetToPtr(rowSlot->offset)); 275 return &fieldDir[column]; 276 } 277 278 status_t CursorWindow::putBlob(uint32_t row, uint32_t column, const void* value, size_t size) { 279 return putBlobOrString(row, column, value, size, FIELD_TYPE_BLOB); 280 } 281 282 status_t CursorWindow::putString(uint32_t row, uint32_t column, const char* value, 283 size_t sizeIncludingNull) { 284 return putBlobOrString(row, column, value, sizeIncludingNull, FIELD_TYPE_STRING); 285 } 286 287 status_t CursorWindow::putBlobOrString(uint32_t row, uint32_t column, 288 const void* value, size_t size, int32_t type) { 289 if (mReadOnly) { 290 return INVALID_OPERATION; 291 } 292 293 FieldSlot* fieldSlot = getFieldSlot(row, column); 294 if (!fieldSlot) { 295 return BAD_VALUE; 296 } 297 298 uint32_t offset = alloc(size); 299 if (!offset) { 300 return NO_MEMORY; 301 } 302 303 memcpy(offsetToPtr(offset), value, size); 304 305 fieldSlot->type = type; 306 fieldSlot->data.buffer.offset = offset; 307 fieldSlot->data.buffer.size = size; 308 return OK; 309 } 310 311 status_t CursorWindow::putLong(uint32_t row, uint32_t column, int64_t value) { 312 if (mReadOnly) { 313 return INVALID_OPERATION; 314 } 315 316 FieldSlot* fieldSlot = getFieldSlot(row, column); 317 if (!fieldSlot) { 318 return BAD_VALUE; 319 } 320 321 fieldSlot->type = FIELD_TYPE_INTEGER; 322 fieldSlot->data.l = value; 323 return OK; 324 } 325 326 status_t CursorWindow::putDouble(uint32_t row, uint32_t column, double value) { 327 if (mReadOnly) { 328 return INVALID_OPERATION; 329 } 330 331 FieldSlot* fieldSlot = getFieldSlot(row, column); 332 if (!fieldSlot) { 333 return BAD_VALUE; 334 } 335 336 fieldSlot->type = FIELD_TYPE_FLOAT; 337 fieldSlot->data.d = value; 338 return OK; 339 } 340 341 status_t CursorWindow::putNull(uint32_t row, uint32_t column) { 342 if (mReadOnly) { 343 return INVALID_OPERATION; 344 } 345 346 FieldSlot* fieldSlot = getFieldSlot(row, column); 347 if (!fieldSlot) { 348 return BAD_VALUE; 349 } 350 351 fieldSlot->type = FIELD_TYPE_NULL; 352 fieldSlot->data.buffer.offset = 0; 353 fieldSlot->data.buffer.size = 0; 354 return OK; 355 } 356 357 }; // namespace android 358