Add "log.h", which should have been part of the previous commit.

FossilOrigin-Name: 8de9f010044fc992b5b45a7bb0da1284b404ecdb

manifest

@@ -1,5 +1,5 @@
-C Import\sexperimental\swrite-ahead-logging\scode.
-D 2010-04-12T19:00:30
+C Add\s"log.h",\swhich\sshould\shave\sbeen\spart\sof\sthe\sprevious\scommit.
+D 2010-04-12T19:05:58
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 4f2f967b7e58a35bb74fb7ec8ae90e0f4ca7868b
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -132,6 +132,7 @@ F src/legacy.c a199d7683d60cef73089e892409113e69c23a99f
 F src/lempar.c 7f026423f4d71d989e719a743f98a1cbd4e6d99e
 F src/loadext.c 1c7a61ce1281041f437333f366a96aa0d29bb581
 F src/log.c 6e8f296f6c566a297cd074c4165f1695fd1df5b7
+F src/log.h e691f7d935d6a8ad63b9de2e6014627056f01e1a
 F src/main.c c0e7192bad5b90544508b241eb2487ac661de890
 F src/malloc.c a08f16d134f0bfab6b20c3cd142ebf3e58235a6a
 F src/mem0.c 6a55ebe57c46ca1a7d98da93aaa07f99f1059645
@@ -802,11 +803,7 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 51a613950824698687c0db83b7884db33d45f7f5
-R d1eaede94883ac0829acce36d14527da
-T *bgcolor * #ffd0c0
-T *branch * wal
-T *sym-wal *
-T -sym-trunk *
+P 409d61baeb0a19d1700c973f16c8acef7b8506cd
+R 05e422fded750e42fd289d80ab078a37
 U dan
-Z 9f87e000c4066ee64fca3bc82365cd7e
+Z 97a0dd7c04bfbe6a9f80405a5df46925

manifest.uuid

@@ -1 +1 @@
-409d61baeb0a19d1700c973f16c8acef7b8506cd
+8de9f010044fc992b5b45a7bb0da1284b404ecdb

src/log.h

@@ -0,0 +1,61 @@
+/*
+** 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 _LOG_H_
+#define _LOG_H_
+
+#include "sqliteInt.h"
+
+/* Flags that may be set in the 'flags' argument to sqlite3LogWrite(): */
+#define LOG_MASK_COMMIT        0x08
+#define LOG_MASK_MASTERJOURNAL 0x10
+#define LOG_MASK_TRUNCATE      0x20
+
+
+#define LOG_TRUNCATE_BIT       0x80000000 
+
+/* 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 sqlite3LogOpen(sqlite3_vfs*, const char *zDb, Log **ppLog);
+int sqlite3LogClose(Log *pLog, sqlite3_file *pFd, u8 *zBuf);
+
+/* Configure the log connection. */
+void sqlite3LogSetSyncflags(Log *, int sync_flags);
+
+/* Used by readers to open (lock) and close (unlock) a database snapshot. */
+int sqlite3LogOpenSnapshot(Log *pLog, int *);
+void sqlite3LogCloseSnapshot(Log *pLog);
+
+/* Read a page from the log, if it is present. */
+int sqlite3LogRead(Log *pLog, Pgno pgno, int *pInLog, u8 *pOut);
+void sqlite3LogMaxpgno(Log *pLog, Pgno *pPgno);
+
+/* Obtain or release the WRITER lock. */
+int sqlite3LogWriteLock(Log *pLog, int op);
+
+/* Write a segment to the log. */
+int sqlite3LogFrames(Log *pLog, int, PgHdr *, Pgno, int, int);
+
+/* Copy pages from the log to the database file */ 
+int sqlite3LogCheckpoint(
+  Log *pLog,                      /* Log connection */
+  sqlite3_file *pFd,              /* File descriptor open on db file */
+  u8 *zBuf                        /* Temporary buffer to use */
+);
+
+#endif /* _LOG_H_ */