page CRC calculating

storage/maria/ma_pagecrc.c:
  New BitKeeper file ``storage/maria/ma_pagecrc.c''

storage/maria/ma_pagecrc.c

+/* TODO: copyright & Co */
+
+#include "maria_def.h"
+
+
+/**
+  @brief calculate crc of the page avoiding special values
+
+  @param start           The value to start CRC (we use page number here)
+  @param data            data pointer
+  @param length          length of the data
+
+  @return crc of the page without special values
+*/
+
+static uint32 maria_page_crc(ulong start, uchar *data, uint length)
+{
+  uint32 crc= crc32(start, data, length);
+
+  /* we need this assert to get following comparison working */
+  compile_time_assert(MARIA_NO_CRC_BITMAP_PAGE ==
+                      MARIA_NO_CRC_NORMAL_PAGE - 1 &&
+                      MARIA_NO_CRC_NORMAL_PAGE == 0xffffffff);
+  if (crc >= MARIA_NO_CRC_BITMAP_PAGE)
+    crc= MARIA_NO_CRC_BITMAP_PAGE - 1;
+
+  return(crc);
+}
+
+/**
+  @brief Maria pages read callback (checks the page CRC)
+
+  @param page            The page data to check
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        pointer to MARIA_SHARE
+  @param no_crc_val      Value which means CRC absence
+                         (MARIA_NO_CRC_NORMAL_PAGE or MARIA_NO_CRC_BITMAP_PAGE)
+  @param data_length     length of data to calculate CRC
+
+  @retval 0 OK
+  @retval 1 Error
+*/
+
+static inline my_bool maria_page_crc_check(uchar *page,
+                                           pgcache_page_no_t page_no,
+                                           MARIA_SHARE *share,
+                                           uint32 no_crc_val,
+                                           int data_length)
+{
+  uint32 crc= uint4korr(page + share->block_size - CRC_SIZE), new_crc;
+  my_bool res;
+  DBUG_ENTER("maria_page_crc_check");
+
+  DBUG_ASSERT((uint)data_length <= share->block_size - CRC_SIZE);
+
+  /* we need this assert to get following comparison working */
+  compile_time_assert(MARIA_NO_CRC_BITMAP_PAGE ==
+                      MARIA_NO_CRC_NORMAL_PAGE - 1 &&
+                      MARIA_NO_CRC_NORMAL_PAGE == 0xffffffff);
+  /*
+    If crc is no_crc_val then
+    the page has no crc, so there is nothing to check.
+  */
+  if (crc >= MARIA_NO_CRC_BITMAP_PAGE)
+  {
+    DBUG_PRINT("info", ("No crc: (0x%lx)  crc: (0x%lx) page: %lu  ",
+                        (ulong) no_crc_val, (ulong) crc, (ulong) page_no));
+#ifndef DBUG_OFF
+    if (crc != no_crc_val)
+      DBUG_PRINT("CRCerror", ("Wrong no CRC value"));
+#endif
+    DBUG_RETURN(test(crc != no_crc_val));
+  }
+  new_crc= maria_page_crc(page_no, page, data_length);
+  DBUG_ASSERT(new_crc != no_crc_val);
+  res= test(new_crc != crc);
+  if (res)
+  {
+    DBUG_PRINT("CRCerror", ("Page: %lu  crc: 0x%lx  calculated crc: 0x%lx",
+                            (ulong) page_no, (ulong) crc, (ulong) new_crc));
+    maria_mark_crashed_share(share);
+  }
+  DBUG_RETURN(res);
+}
+
+
+/**
+  @brief Maria pages write callback (sets the page CRC for data and index
+  files)
+
+  @param page            The page data to set
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        Write callback data pointer (pointer to MARIA_SHARE)
+
+  @retval 0 OK
+*/
+
+my_bool maria_page_crc_set_normal(uchar *page,
+                                  pgcache_page_no_t page_no,
+                                  uchar* data_ptr)
+{
+  MARIA_SHARE *share= (MARIA_SHARE *)data_ptr;
+  int data_length= share->block_size - CRC_SIZE;
+  uint32 crc= maria_page_crc(page_no, page, data_length);
+  DBUG_ENTER("maria_page_crc_set");
+
+  DBUG_PRINT("info", ("Page %u  crc: 0x%lx",
+                      (uint)page_no, (ulong)crc));
+
+  /* crc is on the stack so it is aligned, pagecache buffer is aligned, too */
+  int4store_aligned(page + data_length, crc);
+  DBUG_RETURN(0);
+}
+
+
+/**
+  @brief Maria pages write callback (sets the page CRC for keys)
+
+  @param page            The page data to set
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        Write callback data pointer (pointer to MARIA_SHARE)
+
+  @retval 0 OK
+*/
+
+my_bool maria_page_crc_set_index(uchar *page,
+                                 pgcache_page_no_t page_no,
+                                 uchar* data_ptr)
+{
+  MARIA_SHARE *share= (MARIA_SHARE *)data_ptr;
+  int data_length= _ma_get_page_used(share, page);
+  uint32 crc= maria_page_crc(page_no, page, data_length);
+  DBUG_ENTER("maria_page_crc_set");
+
+  DBUG_PRINT("info", ("Page %u  crc: 0x%lx",
+                      (uint)page_no, (ulong)crc));
+  DBUG_ASSERT((uint)data_length <= share->block_size - CRC_SIZE);
+  /* crc is on the stack so it is aligned, pagecache buffer is aligned, too */
+  int4store_aligned(page + share->block_size - CRC_SIZE, crc);
+  DBUG_RETURN(0);
+}
+
+
+/* interface functions */
+
+
+/**
+  @brief Maria pages read callback (checks the page CRC) for index/data pages
+
+  @param page            The page data to check
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        Read callback data pointer (pointer to MARIA_SHARE)
+
+  @retval 0 OK
+  @retval 1 Error
+*/
+
+my_bool maria_page_crc_check_data(uchar *page,
+                                  pgcache_page_no_t page_no,
+                                  uchar* data_ptr)
+{
+  MARIA_SHARE *share= (MARIA_SHARE *)data_ptr;
+  return (maria_page_crc_check(page, page_no, share,
+                               MARIA_NO_CRC_NORMAL_PAGE,
+                               share->block_size - CRC_SIZE));
+}
+
+
+/**
+  @brief Maria pages read callback (checks the page CRC) for bitmap pages
+
+  @param page            The page data to check
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        Read callback data pointer (pointer to MARIA_SHARE)
+
+  @retval 0 OK
+  @retval 1 Error
+*/
+
+my_bool maria_page_crc_check_bitmap(uchar *page,
+                                    pgcache_page_no_t page_no,
+                                    uchar* data_ptr)
+{
+  MARIA_SHARE *share= (MARIA_SHARE *)data_ptr;
+  return (maria_page_crc_check(page, page_no, share,
+                               MARIA_NO_CRC_BITMAP_PAGE,
+                               share->block_size - CRC_SIZE));
+}
+
+
+/**
+  @brief Maria pages read callback (checks the page CRC) for index pages
+
+  @param page            The page data to check
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        Read callback data pointer (pointer to MARIA_SHARE)
+
+  @retval 0 OK
+  @retval 1 Error
+*/
+
+my_bool maria_page_crc_check_index(uchar *page,
+                                   pgcache_page_no_t page_no,
+                                   uchar* data_ptr)
+{
+  MARIA_SHARE *share= (MARIA_SHARE *)data_ptr;
+  return (maria_page_crc_check(page, page_no, share,
+                               MARIA_NO_CRC_NORMAL_PAGE,
+                               _ma_get_page_used(share, page)));
+}
+
+
+/**
+  @brief Maria pages write callback (sets the page filler for index/data)
+
+  @param page            The page data to set
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        Write callback data pointer (pointer to MARIA_SHARE)
+
+  @retval 0 OK
+*/
+
+my_bool maria_page_filler_set_normal(uchar *page,
+                                     __attribute__((unused))
+                                     pgcache_page_no_t page_no,
+                                     uchar* data_ptr)
+{
+  DBUG_ENTER("maria_page_filler_set_normal");
+  int4store_aligned(page + ((MARIA_SHARE *)data_ptr)->block_size - CRC_SIZE,
+                    MARIA_NO_CRC_NORMAL_PAGE);
+  DBUG_RETURN(0);
+}
+
+/**
+  @brief Maria pages write callback (sets the page filler for bitmap)
+
+  @param page            The page data to set
+  @param page_no         The page number (<offset>/<page length>)
+  @param data_ptr        Write callback data pointer (pointer to MARIA_SHARE)
+
+  @retval 0 OK
+*/
+
+my_bool maria_page_filler_set_bitmap(uchar *page,
+                                     __attribute__((unused))
+                                     pgcache_page_no_t page_no,
+                                     uchar* data_ptr)
+{
+  DBUG_ENTER("maria_page_filler_set_bitmap");
+  int4store_aligned(page + ((MARIA_SHARE *)data_ptr)->block_size - CRC_SIZE,
+                    MARIA_NO_CRC_BITMAP_PAGE);
+  DBUG_RETURN(0);
+}