SQLite: Check-in [b369980f]

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Overview

Comment:	Improvements to a comment in the pcache.c file. No changes to code.
Downloads:	Tarball \| ZIP archive \| SQL archive
Timelines:	family \| ancestors \| descendants \| both \| trunk
Files:	files \| file ages \| folders
SHA1:	b369980f0c4550a9034833caa2c7c85d6030f5ff
User & Date:	drh 2016-05-13 17:22:33

Context

2016-05-16
11:55		Disable shell.exe test cases for UTF8 filenames as they do not work on MinGW. check-in: 386bcbba user: drh tags: trunk
2016-05-13
17:22		Improvements to a comment in the pcache.c file. No changes to code. check-in: b369980f user: drh tags: trunk
15:22		Remove the unused PGHDR_NEED_READ flag. Add invariant checking (during SQLITE_DEBUG builds only) for the PgHdr object. check-in: 771c5411 user: drh tags: trunk

Changes

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Changes to src/pcache.c.

  **    (1)  Page X is journalled, and gets WRITEABLE and NEED_SEEK.
  **    (2)  Page X moved to freelist, WRITEABLE is cleared
  **    (3)  Page X reused, WRITEABLE is set again
  ** If NEED_SYNC had been cleared in step 2, then it would not be reset
  ** in step 3, and page might be written into the database without first
  ** syncing the rollback journal, which might cause corruption on a power
  ** loss.







  */
  return 1;
}
#endif /* SQLITE_DEBUG */


/********************************** Linked List Management ********************/








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  **    (1)  Page X is journalled, and gets WRITEABLE and NEED_SEEK.
  **    (2)  Page X moved to freelist, WRITEABLE is cleared
  **    (3)  Page X reused, WRITEABLE is set again
  ** If NEED_SYNC had been cleared in step 2, then it would not be reset
  ** in step 3, and page might be written into the database without first
  ** syncing the rollback journal, which might cause corruption on a power
  ** loss.
  **
  ** Another example is when the database page size is smaller than the
  ** disk sector size.  When any page of a sector is journalled, all pages
  ** in that sector are marked NEED_SYNC even if they are still CLEAN, just
  ** in case they are later modified, since all pages in the same sector
  ** must be journalled and synced before any of those pages can be safely
  ** written.
  */
  return 1;
}
#endif /* SQLITE_DEBUG */


/********************************** Linked List Management ********************/