Merge "Fix reading extents file if not start from the beginning of a extent."android-cts-7.0_r9android-cts-7.0_r8android-cts-7.0_r7android-cts-7.0_r6android-cts-7.0_r5android-cts-7.0_r4android-cts-7.0_r33android-cts-7.0_r32android-cts-7.0_r31android-cts-7.0_r30android-cts-7.0_r3android-cts-7.0_r29android-cts-7.0_r28android-cts-7.0_r27android-cts-7.0_r26android-cts-7.0_r25android-cts-7.0_r24android-cts-7.0_r23android-cts-7.0_r22android-cts-7.0_r21android-cts-7.0_r20android-cts-7.0_r2android-cts-7.0_r19android-cts-7.0_r18android-cts-7.0_r17android-cts-7.0_r16android-cts-7.0_r15android-cts-7.0_r14android-cts-7.0_r13android-cts-7.0_r12android-cts-7.0_r11android-cts-7.0_r10android-cts-7.0_r1android-7.0.0_r9android-7.0.0_r8android-7.0.0_r7android-7.0.0_r6android-7.0.0_r5android-7.0.0_r4android-7.0.0_r36android-7.0.0_r35android-7.0.0_r34android-7.0.0_r33android-7.0.0_r32android-7.0.0_r31android-7.0.0_r30android-7.0.0_r3android-7.0.0_r29android-7.0.0_r28android-7.0.0_r27android-7.0.0_r24android-7.0.0_r21android-7.0.0_r19android-7.0.0_r17android-7.0.0_r15android-7.0.0_r14android-7.0.0_r13android-7.0.0_r12android-7.0.0_r11android-7.0.0_r10android-7.0.0_r1nougat-releasenougat-mr0.5-releasenougat-devnougat-cts-releasenougat-bugfix-release

am: 2c1607d134

* commit '2c1607d13402172c129d73d76a6a351e78a44328':
  Fix reading extents file if not start from the beginning of a extent.

2 files changed, 31 insertions, 4 deletions

diff --git a/extents_file.cc b/extents_file.cc
index 2d2ea83..01d31a6 100644
--- a/extents_file.cc
+++ b/extents_file.cc
@@ -86,14 +86,15 @@ bool ExtentsFile::IOOperation(bool (FileInterface::*io_op)(T*, size_t, size_t*),
   AdvancePos(0);
   while (count > 0 && curr_ex_idx_ < extents_.size()) {
     const ex_t& ex = extents_[curr_ex_idx_];
-    size_t chunk_size = std::min(static_cast<uint64_t>(count), ex.len);
+    off_t curr_ex_off = curr_pos_ - acc_len_[curr_ex_idx_];
+    size_t chunk_size =
+        std::min(static_cast<uint64_t>(count), ex.len - curr_ex_off);
     size_t chunk_processed = 0;
     if (ex.off < 0) {
       chunk_processed = chunk_size;
     } else {
-      uint64_t file_pos = ex.off + (curr_pos_ - acc_len_[curr_ex_idx_]);
-      if (!file_->Seek(file_pos) ||
-          !((file_.get()->*io_op))(buf, chunk_size, &chunk_processed)) {
+      if (!file_->Seek(ex.off + curr_ex_off) ||
+          !(file_.get()->*io_op)(buf, chunk_size, &chunk_processed)) {
         processed += chunk_processed;
         result = processed > 0;
         break;
diff --git a/extents_file_unittest.cc b/extents_file_unittest.cc
index fa9ed22..73cedb2 100644
--- a/extents_file_unittest.cc
+++ b/extents_file_unittest.cc
@@ -128,6 +128,32 @@ TEST_F(ExtentsFileTest, ReadAcrossAllExtents) {
   EXPECT_EQ(15U, bytes_read);
 }
 
+TEST_F(ExtentsFileTest, MultiReadAcrossAllExtents) {
+  ExtentsFile file(std::move(mock_file_ptr_),
+                   {ex_t{10, 5}, ex_t{20, 7}, {27, 3}});
+  InSequence s;
+  char* buf = reinterpret_cast<char*>(0x1234);
+
+  EXPECT_CALL(*mock_file_, Seek(10)).WillOnce(Return(true));
+  EXPECT_CALL(*mock_file_, Read(buf, 2, _)).WillOnce(SucceedIO());
+  EXPECT_CALL(*mock_file_, Seek(12)).WillOnce(Return(true));
+  EXPECT_CALL(*mock_file_, Read(buf, 3, _)).WillOnce(SucceedIO());
+  EXPECT_CALL(*mock_file_, Seek(20)).WillOnce(Return(true));
+  EXPECT_CALL(*mock_file_, Read(buf + 3, 5, _)).WillOnce(SucceedIO());
+  EXPECT_CALL(*mock_file_, Seek(25)).WillOnce(Return(true));
+  EXPECT_CALL(*mock_file_, Read(buf, 2, _)).WillOnce(SucceedIO());
+  EXPECT_CALL(*mock_file_, Seek(27)).WillOnce(Return(true));
+  EXPECT_CALL(*mock_file_, Read(buf + 2, 3, _)).WillOnce(SucceedIO());
+
+  size_t bytes_read = 0;
+  EXPECT_TRUE(file.Read(buf, 2, &bytes_read));
+  EXPECT_EQ(2U, bytes_read);
+  EXPECT_TRUE(file.Read(buf, 8, &bytes_read));
+  EXPECT_EQ(8U, bytes_read);
+  EXPECT_TRUE(file.Read(buf, 100, &bytes_read));
+  EXPECT_EQ(5U, bytes_read);
+}
+
 TEST_F(ExtentsFileTest, ReadSmallChunks) {
   ExtentsFile file(std::move(mock_file_ptr_), {ex_t{10, 1}, ex_t{20, 10}});
   InSequence s;