Change the names of the log.c and log.h source files to wal.c and wal.h.

FossilOrigin-Name: 56fe5d7624f840417152bcc63efbe21a5f557920

src/wal.h

@@ -0,0 +1,62 @@
+/*
+** 2010 February 1
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This header file defines the interface to the write-ahead logging 
+** system. Refer to the comments below and the header comment attached to 
+** the implementation of each function in log.c for further details.
+*/
+
+#ifndef _WAL_H_
+#define _WAL_H_
+
+#include "sqliteInt.h"
+
+/* Connection to a log file. There is one object of this type for each pager. */
+typedef struct Log Log;
+
+/* Open and close a connection to a log file. */
+int sqlite3WalOpen(sqlite3_vfs*, const char *zDb, Log **ppLog);
+int sqlite3WalClose(Log *pLog, sqlite3_file *pFd, int sync_flags, u8 *zBuf);
+
+/* Used by readers to open (lock) and close (unlock) a snapshot. */
+int sqlite3WalOpenSnapshot(Log *pLog, int *);
+void sqlite3WalCloseSnapshot(Log *pLog);
+
+/* Read a page from the log, if it is present. */
+int sqlite3WalRead(Log *pLog, Pgno pgno, int *pInLog, u8 *pOut);
+void sqlite3WalDbsize(Log *pLog, Pgno *pPgno);
+
+/* Obtain or release the WRITER lock. */
+int sqlite3WalWriteLock(Log *pLog, int op);
+
+/* Undo any frames written (but not committed) to the log */
+int sqlite3WalUndo(Log *pLog, int (*xUndo)(void *, Pgno), void *pUndoCtx);
+
+/* Return true if data has been written but not committed to the log file. */
+int sqlite3WalDirty(Log *pLog);
+
+/* Write a frame or frames to the log. */
+int sqlite3WalFrames(Log *pLog, int, PgHdr *, Pgno, int, int);
+
+/* Copy pages from the log to the database file */ 
+int sqlite3WalCheckpoint(
+  Log *pLog,                      /* Log connection */
+  sqlite3_file *pFd,              /* File descriptor open on db file */
+  int sync_flags,                 /* Flags to sync db file with (or 0) */
+  u8 *zBuf,                       /* Temporary buffer to use */
+  int (*xBusyHandler)(void *),    /* Pointer to busy-handler function */
+  void *pBusyHandlerArg           /* Argument to pass to xBusyHandler */
+);
+
+/* Return the value to pass to a log callback. Or 0 for no callback. */
+int sqlite3WalCallback(Log *pLog);
+
+#endif /* _WAL_H_ */