statement.h

#ifndef STATEMENT
#define STATEMENT

#define size_of_attribute(Struct, Attribute) sizeof(((Struct*)0)->Attribute)

const uint32_t COLUMN_USERNAME_SIZE = 32;
const uint32_t COLUMN_EMAIL_SIZE = 255;

typedef struct {
  uint32_t id;
  char username[COLUMN_USERNAME_SIZE];
  char email[COLUMN_EMAIL_SIZE];
} Row;

const uint32_t ID_OFFSET = 0;
const uint32_t ID_SIZE = size_of_attribute(Row, id);
const uint32_t USERNAME_SIZE = size_of_attribute(Row, username);
const uint32_t EMAIL_SIZE = size_of_attribute(Row, email);
const uint32_t ROW_SIZE = ID_SIZE + USERNAME_SIZE + EMAIL_SIZE;
const uint32_t USERNAME_OFFSET = ID_OFFSET + ID_SIZE;
const uint32_t EMAIL_OFFSET = USERNAME_OFFSET + USERNAME_SIZE;
const uint32_t PAGE_SIZE = 4096;
const uint32_t TABLE_MAX_PAGES = 100;
const uint32_t ROWS_PER_PAGE = PAGE_SIZE / ROW_SIZE;
const uint32_t TABLE_MAX_ROWS = ROWS_PER_PAGE * TABLE_MAX_PAGES;

typedef enum {
  STATEMENT_INSERT,
  STATEMENT_SELECT
} StatementType;

typedef struct {
  StatementType type;
  Row row_to_insert;
} Statement;

class Table {
  public:
    void* pages[TABLE_MAX_PAGES];
    uint32_t num_rows;

    Table();
};


PrepareResult prepare_statement(InputBuffer* input_buffer, Statement* statement);
ExecuteResult execute_insert(Statement* statement, Table* table);
ExecuteResult execute_select(Statement* statement, Table* table);
ExecuteResult execute_statement(Statement* statement, Table* table);

void serialize_row(Row* source, void* destination);
void deserialize_row(void* source, Row* destination);

void* row_slot(Table* table, uint32_t row_num);
void print_row(Row* row);

#endif  /* STATEMENT */