Fixed lp:970528 "Server crashes in my_strnncollsp_simple on LEFT JOIN with CSV table, TEXT field"

The main problem was a bug in CSV where it provided wrong statistics (it claimed the table was empty when it wasn't)
I also fixed wrong freeing of blob's in the CSV handler. (Any call to handler::read_first_row() on a CSV table with blobs would fail)



mysql-test/r/csv.result:
  Added new test case
mysql-test/r/partition_innodb.result:
  Updated test results after fixing bug with impossible partitions and const tables
mysql-test/t/csv.test:
  Added new test case
sql/sql_select.cc:
  Cleaned up code for handling of partitions.
  Fixed also a bug where we didn't threat a table with impossible partitions as a const table.
storage/csv/ha_tina.cc:
  Allocate blobroot onces.

2 files changed, 20 insertions, 11 deletions

diff --git a/storage/csv/ha_tina.cc b/storage/csv/ha_tina.cc
index 3a6b2b1578c..d2af7d9e713 100644
--- a/storage/csv/ha_tina.cc
+++ b/storage/csv/ha_tina.cc
@@ -854,6 +854,7 @@ int ha_tina::open(const char *name, int mode, uint open_options)
   */
   thr_lock_data_init(&share->lock, &lock, (void*) this);
   ref_length= sizeof(my_off_t);
+  init_alloc_root(&blobroot, BLOB_MEMROOT_ALLOC_SIZE, 0);
 
   share->lock.get_status= tina_get_status;
   share->lock.update_status= tina_update_status;
@@ -871,6 +872,7 @@ int ha_tina::close(void)
 {
   int rc= 0;
   DBUG_ENTER("ha_tina::close");
+  free_root(&blobroot, MYF(0));
   rc= my_close(data_file, MYF(0));
   DBUG_RETURN(free_share(share) || rc);
 }
@@ -1086,11 +1088,9 @@ int ha_tina::rnd_init(bool scan)
 
   current_position= next_position= 0;
   stats.records= 0;
-  records_is_known= 0;
+  records_is_known= found_end_of_file= 0;
   chain_ptr= chain;
 
-  init_alloc_root(&blobroot, BLOB_MEMROOT_ALLOC_SIZE, 0);
-
   DBUG_RETURN(0);
 }
 
@@ -1122,10 +1122,16 @@ int ha_tina::rnd_next(uchar *buf)
 
   /* don't scan an empty file */
   if (!local_saved_data_file_length)
+  {
+    found_end_of_file= 1;
     DBUG_RETURN(HA_ERR_END_OF_FILE);
-
+  }
   if ((rc= find_current_row(buf)))
+  {
+    DBUG_PRINT("warning", ("got error %d while reading file", rc));
+    found_end_of_file= (rc == HA_ERR_END_OF_FILE);
     DBUG_RETURN(rc);
+  }
 
   stats.records++;
   DBUG_RETURN(0);
@@ -1220,8 +1226,7 @@ int ha_tina::rnd_end()
   my_off_t file_buffer_start= 0;
   DBUG_ENTER("ha_tina::rnd_end");
 
-  free_root(&blobroot, MYF(0));
-  records_is_known= 1;
+  records_is_known= found_end_of_file;
 
   if ((chain_ptr - chain)  > 0)
   {
@@ -1394,8 +1399,6 @@ int ha_tina::repair(THD* thd, HA_CHECK_OPT* check_opt)
   /* set current position to the beginning of the file */
   current_position= next_position= 0;
 
-  init_alloc_root(&blobroot, BLOB_MEMROOT_ALLOC_SIZE, 0);
-
   /* Read the file row-by-row. If everything is ok, repair is not needed. */
   while (!(rc= find_current_row(buf)))
   {
@@ -1603,8 +1606,6 @@ int ha_tina::check(THD* thd, HA_CHECK_OPT* check_opt)
   /* set current position to the beginning of the file */
   current_position= next_position= 0;
 
-  init_alloc_root(&blobroot, BLOB_MEMROOT_ALLOC_SIZE, 0);
-
   /* Read the file row-by-row. If everything is ok, repair is not needed. */
   while (!(rc= find_current_row(buf)))
   {
@@ -1628,6 +1629,13 @@ int ha_tina::check(THD* thd, HA_CHECK_OPT* check_opt)
 }
 
 
+int ha_tina::reset(void)
+{
+  free_root(&blobroot, MYF(0));
+  return 0;
+}
+
+
 bool ha_tina::check_if_incompatible_data(HA_CREATE_INFO *info,
 					   uint table_changes)
 {
diff --git a/storage/csv/ha_tina.h b/storage/csv/ha_tina.h
index 54860ecb3fb..a124ea77f3c 100644
--- a/storage/csv/ha_tina.h
+++ b/storage/csv/ha_tina.h
@@ -84,7 +84,7 @@ class ha_tina: public handler
   uchar chain_alloced;
   uint32 chain_size;
   uint local_data_file_version;  /* Saved version of the data file used */
-  bool records_is_known;
+  bool records_is_known, found_end_of_file;
   MEM_ROOT blobroot;
 
 private:
@@ -156,6 +156,7 @@ public:
   bool auto_repair() const { return 1; }
   void position(const uchar *record);
   int info(uint);
+  int reset();
   int extra(enum ha_extra_function operation);
   int delete_all_rows(void);
   int create(const char *name, TABLE *form, HA_CREATE_INFO *create_info);