implenment record iterator

src/observer/storage/common/record_manager.cpp

@@ -390,6 +390,13 @@ RC RecordFileScanner::open_scan(DiskBufferPool &buffer_pool, ConditionFilter *co
 RC RecordFileScanner::fetch_next_record()
 {
   RC rc = RC::SUCCESS;
+  if (record_page_iterator_.is_valid()) {
+    rc = fetch_next_record_in_page();
+    if (rc == RC::SUCCESS || rc != RC::RECORD_EOF) {
+      return rc;
+    }
+  }
+
   while (bp_iterator_.has_next()) {
     PageNum page_num = bp_iterator_.next();
     record_page_handler_.cleanup();
@@ -400,7 +407,7 @@ RC RecordFileScanner::fetch_next_record()
     }
 
     record_page_iterator_.init(record_page_handler_);
-    rc = fetch_record_in_page();
+    rc = fetch_next_record_in_page();
     if (rc == RC::SUCCESS || rc != RC::RECORD_EOF) {
       return rc;
     }
@@ -409,7 +416,7 @@ RC RecordFileScanner::fetch_next_record()
   return RC::RECORD_EOF;
 }
 
-RC RecordFileScanner::fetch_record_in_page()
+RC RecordFileScanner::fetch_next_record_in_page()
 {
   RC rc = RC::SUCCESS;
   while (record_page_iterator_.has_next()) {

src/observer/storage/common/record_manager.h

@@ -24,11 +24,11 @@ typedef int32_t SlotNum;
 class ConditionFilter;
 
 struct PageHeader {
-  int record_num;           // 当前页面记录的个数
-  int record_capacity;      // 最大记录个数
-  int record_real_size;     // 每条记录的实际大小
-  int record_size;          // 每条记录占用实际空间大小(可能对齐)
-  int first_record_offset;  // 第一条记录的偏移量
+  int32_t record_num;           // 当前页面记录的个数
+  int32_t record_capacity;      // 最大记录个数
+  int32_t record_real_size;     // 每条记录的实际大小
+  int32_t record_size;          // 每条记录占用实际空间大小(可能对齐)
+  int32_t first_record_offset;  // 第一条记录的偏移量
 };
 
 struct RID {
@@ -108,6 +108,9 @@ public:
   bool has_next();
   RC   next(Record &record);
 
+  bool is_valid() const {
+    return record_page_handler_ != nullptr;
+  }
 private:
   RecordPageHandler *record_page_handler_ = nullptr;
   PageNum page_num_ = BP_INVALID_PAGE_NUM;
@@ -227,7 +230,7 @@ public:
 
 private:
   RC fetch_next_record();
-  RC fetch_record_in_page();
+  RC fetch_next_record_in_page();
 private:
   DiskBufferPool *disk_buffer_pool_ = nullptr;
 

src/observer/storage/default/disk_buffer_pool.cpp

@@ -106,12 +106,12 @@ RC BufferPoolIterator::init(DiskBufferPool &bp, PageNum start_page /* = 0 */)
 
 bool BufferPoolIterator::has_next()
 {
-  return bitmap_.next_setted_bit(current_page_num_) != -1;
+  return bitmap_.next_setted_bit(current_page_num_ + 1) != -1;
 }
 
 PageNum BufferPoolIterator::next()
 {
-  PageNum next_page = bitmap_.next_setted_bit(current_page_num_);
+  PageNum next_page = bitmap_.next_setted_bit(current_page_num_ + 1);
   if (next_page != -1) {
     current_page_num_ = next_page;
   }

unitest/record_manager_test.cpp

@@ -102,6 +102,81 @@ TEST(test_record_page_handler, test_record_page_handler)
     ASSERT_EQ(rc, RC::SUCCESS);
   }
   ASSERT_EQ(count, 6);
+
+  bpm->close_file(record_manager_file);
+}
+
+TEST(test_record_page_handler, test_record_file_iterator)
+{
+  const char *record_manager_file = "record_manager.bp";
+  ::remove(record_manager_file);
+
+  BufferPoolManager *bpm = new BufferPoolManager();
+  DiskBufferPool *bp = nullptr;
+  RC rc = bpm->create_file(record_manager_file);
+  ASSERT_EQ(rc, RC::SUCCESS);
+  
+  rc = bpm->open_file(record_manager_file, bp);
+  ASSERT_EQ(rc, RC::SUCCESS);
+
+  RecordFileHandler file_handler;
+  rc = file_handler.init(bp);
+  ASSERT_EQ(rc, RC::SUCCESS);
+
+  RecordFileScanner file_scanner;
+  rc = file_scanner.open_scan(*bp, nullptr);
+  ASSERT_EQ(rc, RC::SUCCESS);
+
+  int count = 0;
+  Record record;
+  while (file_scanner.has_next()) {
+    rc = file_scanner.next(record);
+    ASSERT_EQ(rc, RC::SUCCESS);
+    count++;
+  }
+  file_scanner.close_scan();
+  ASSERT_EQ(count, 0);
+  
+  const int record_insert_num = 1000;
+  char record_data[20];
+  std::vector<RID> rids;
+  for (int i = 0; i < record_insert_num; i++) {
+    RID rid;
+    rc = file_handler.insert_record(record_data, sizeof(record_data), &rid);
+    ASSERT_EQ(rc, RC::SUCCESS);
+    rids.push_back(rid);
+  }
+
+  rc = file_scanner.open_scan(*bp, nullptr);
+  ASSERT_EQ(rc, RC::SUCCESS);
+
+  count = 0;
+  while (file_scanner.has_next()) {
+    rc = file_scanner.next(record);
+    ASSERT_EQ(rc, RC::SUCCESS);
+    count++;
+  }
+  file_scanner.close_scan();
+  ASSERT_EQ(count, rids.size());
+  
+  for (int i = 0; i < record_insert_num; i += 2) {
+    rc = file_handler.delete_record(&rids[i]);
+    ASSERT_EQ(rc, RC::SUCCESS);
+  }
+
+  rc = file_scanner.open_scan(*bp, nullptr);
+  ASSERT_EQ(rc, RC::SUCCESS);
+
+  count = 0;
+  while (file_scanner.has_next()) {
+    rc = file_scanner.next(record);
+    ASSERT_EQ(rc, RC::SUCCESS);
+    count++;
+  }
+  file_scanner.close_scan();
+  ASSERT_EQ(count, rids.size() / 2);
+  
+  bpm->close_file(record_manager_file);
 }
 
 int main(int argc, char **argv)