diff options
Diffstat (limited to 'src/tclsqlite.c')
| -rw-r--r-- | src/tclsqlite.c | 132 |
1 files changed, 124 insertions, 8 deletions
diff --git a/src/tclsqlite.c b/src/tclsqlite.c index 69f70bd41..dd21cad4e 100644 --- a/src/tclsqlite.c +++ b/src/tclsqlite.c @@ -11,7 +11,7 @@ ************************************************************************* ** A TCL Interface to SQLite ** -** $Id: tclsqlite.c,v 1.45 2003/03/30 19:17:03 drh Exp $ +** $Id: tclsqlite.c,v 1.46 2003/04/03 15:46:04 drh Exp $ */ #ifndef NO_TCL /* Omit this whole file if TCL is unavailable */ @@ -51,6 +51,8 @@ struct SqliteDb { sqlite *db; /* The "real" database structure */ Tcl_Interp *interp; /* The interpreter used for this database */ char *zBusy; /* The busy callback routine */ + char *zBegin; /* The begin-transaction callback routine */ + char *zCommit; /* The commit-transaction callback routine */ SqlFunc *pFunc; /* List of SQL functions */ int rc; /* Return code of most recent sqlite_exec() */ }; @@ -260,6 +262,12 @@ static void DbDeleteCmd(void *db){ if( pDb->zBusy ){ Tcl_Free(pDb->zBusy); } + if( pDb->zBegin ){ + Tcl_Free(pDb->zBegin); + } + if( pDb->zCommit ){ + Tcl_Free(pDb->zCommit); + } Tcl_Free((char*)pDb); } @@ -289,6 +297,39 @@ static int DbBusyHandler(void *cd, const char *zTable, int nTries){ } /* +** This routine is called when a new transaction is started. The +** TCL script in pDb->zBegin is executed. If it returns non-zero or +** if it throws an exception, the transaction is aborted. +*/ +static int DbBeginHandler(void *cd){ + SqliteDb *pDb = (SqliteDb*)cd; + int rc; + + rc = Tcl_Eval(pDb->interp, pDb->zBegin); + if( rc!=TCL_OK || atoi(Tcl_GetStringResult(pDb->interp)) ){ + return 1; + } + return 0; +} + +/* +** This routine is called when a transaction is committed. The +** TCL script in pDb->zCommit is executed. If it returns non-zero or +** if it throws an exception, the transaction is rolled back instead +** of being committed. +*/ +static int DbCommitHandler(void *cd){ + SqliteDb *pDb = (SqliteDb*)cd; + int rc; + + rc = Tcl_Eval(pDb->interp, pDb->zCommit); + if( rc!=TCL_OK || atoi(Tcl_GetStringResult(pDb->interp)) ){ + return 1; + } + return 0; +} + +/* ** This routine is called to evaluate an SQL function implemented ** using TCL script. */ @@ -328,15 +369,16 @@ static int DbObjCmd(void *cd, Tcl_Interp *interp, int objc,Tcl_Obj *const*objv){ SqliteDb *pDb = (SqliteDb*)cd; int choice; static const char *DB_strs[] = { - "busy", "changes", "close", - "complete", "errorcode", "eval", - "function", "last_insert_rowid", "timeout", - 0 + "begin_hook", "busy", "changes", + "close", "commit_hook", "complete", + "errorcode", "eval", "function", + "last_insert_rowid", "timeout", 0 }; enum DB_enum { - DB_BUSY, DB_CHANGES, DB_CLOSE, - DB_COMPLETE, DB_ERRORCODE, DB_EVAL, - DB_FUNCTION, DB_LAST_INSERT_ROWID,DB_TIMEOUT, + DB_BEGIN_HOOK, DB_BUSY, DB_CHANGES, + DB_CLOSE, DB_COMMIT_HOOK, DB_COMPLETE, + DB_ERRORCODE, DB_EVAL, DB_FUNCTION, + DB_LAST_INSERT_ROWID, DB_TIMEOUT, }; if( objc<2 ){ @@ -349,6 +391,43 @@ static int DbObjCmd(void *cd, Tcl_Interp *interp, int objc,Tcl_Obj *const*objv){ switch( (enum DB_enum)choice ){ + /* $db begin_callback ?CALLBACK? + ** + ** Invoke the given callback at the beginning of every SQL transaction. + ** If the callback throws an exception or returns non-zero, then the + ** transaction is aborted. If CALLBACK is an empty string, the callback + ** is disabled. + */ + case DB_BEGIN_HOOK: { + if( objc>3 ){ + Tcl_WrongNumArgs(interp, 2, objv, "?CALLBACK?"); + }else if( objc==2 ){ + if( pDb->zBegin ){ + Tcl_AppendResult(interp, pDb->zBegin, 0); + } + }else{ + char *zBegin; + int len; + if( pDb->zBegin ){ + Tcl_Free(pDb->zBegin); + } + zBegin = Tcl_GetStringFromObj(objv[2], &len); + if( zBegin && len>0 ){ + pDb->zBegin = Tcl_Alloc( len + 1 ); + strcpy(pDb->zBegin, zBegin); + }else{ + pDb->zBegin = 0; + } + if( pDb->zBegin ){ + pDb->interp = interp; + sqlite_begin_hook(pDb->db, DbBeginHandler, pDb); + }else{ + sqlite_begin_hook(pDb->db, 0, 0); + } + } + break; + } + /* $db busy ?CALLBACK? ** ** Invoke the given callback if an SQL statement attempts to open @@ -413,6 +492,43 @@ static int DbObjCmd(void *cd, Tcl_Interp *interp, int objc,Tcl_Obj *const*objv){ break; } + /* $db commit_hook ?CALLBACK? + ** + ** Invoke the given callback just before committing every SQL transaction. + ** If the callback throws an exception or returns non-zero, then the + ** transaction is aborted. If CALLBACK is an empty string, the callback + ** is disabled. + */ + case DB_COMMIT_HOOK: { + if( objc>3 ){ + Tcl_WrongNumArgs(interp, 2, objv, "?CALLBACK?"); + }else if( objc==2 ){ + if( pDb->zCommit ){ + Tcl_AppendResult(interp, pDb->zCommit, 0); + } + }else{ + char *zCommit; + int len; + if( pDb->zCommit ){ + Tcl_Free(pDb->zCommit); + } + zCommit = Tcl_GetStringFromObj(objv[2], &len); + if( zCommit && len>0 ){ + pDb->zCommit = Tcl_Alloc( len + 1 ); + strcpy(pDb->zCommit, zCommit); + }else{ + pDb->zCommit = 0; + } + if( pDb->zCommit ){ + pDb->interp = interp; + sqlite_commit_hook(pDb->db, DbCommitHandler, pDb); + }else{ + sqlite_commit_hook(pDb->db, 0, 0); + } + } + break; + } + /* $db complete SQL ** ** Return TRUE if SQL is a complete SQL statement. Return FALSE if |