Index: third_party/sqlite/sqlite-src-3070603/src/walker.c |
diff --git a/third_party/sqlite/sqlite-src-3070603/src/walker.c b/third_party/sqlite/sqlite-src-3070603/src/walker.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..c95a9c169db3125ad877cca14d88abd13495ac21 |
--- /dev/null |
+++ b/third_party/sqlite/sqlite-src-3070603/src/walker.c |
@@ -0,0 +1,136 @@ |
+/* |
+** 2008 August 16 |
+** |
+** 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 file contains routines used for walking the parser tree for |
+** an SQL statement. |
+*/ |
+#include "sqliteInt.h" |
+#include <stdlib.h> |
+#include <string.h> |
+ |
+ |
+/* |
+** Walk an expression tree. Invoke the callback once for each node |
+** of the expression, while decending. (In other words, the callback |
+** is invoked before visiting children.) |
+** |
+** The return value from the callback should be one of the WRC_* |
+** constants to specify how to proceed with the walk. |
+** |
+** WRC_Continue Continue descending down the tree. |
+** |
+** WRC_Prune Do not descend into child nodes. But allow |
+** the walk to continue with sibling nodes. |
+** |
+** WRC_Abort Do no more callbacks. Unwind the stack and |
+** return the top-level walk call. |
+** |
+** The return value from this routine is WRC_Abort to abandon the tree walk |
+** and WRC_Continue to continue. |
+*/ |
+int sqlite3WalkExpr(Walker *pWalker, Expr *pExpr){ |
+ int rc; |
+ if( pExpr==0 ) return WRC_Continue; |
+ testcase( ExprHasProperty(pExpr, EP_TokenOnly) ); |
+ testcase( ExprHasProperty(pExpr, EP_Reduced) ); |
+ rc = pWalker->xExprCallback(pWalker, pExpr); |
+ if( rc==WRC_Continue |
+ && !ExprHasAnyProperty(pExpr,EP_TokenOnly) ){ |
+ if( sqlite3WalkExpr(pWalker, pExpr->pLeft) ) return WRC_Abort; |
+ if( sqlite3WalkExpr(pWalker, pExpr->pRight) ) return WRC_Abort; |
+ if( ExprHasProperty(pExpr, EP_xIsSelect) ){ |
+ if( sqlite3WalkSelect(pWalker, pExpr->x.pSelect) ) return WRC_Abort; |
+ }else{ |
+ if( sqlite3WalkExprList(pWalker, pExpr->x.pList) ) return WRC_Abort; |
+ } |
+ } |
+ return rc & WRC_Abort; |
+} |
+ |
+/* |
+** Call sqlite3WalkExpr() for every expression in list p or until |
+** an abort request is seen. |
+*/ |
+int sqlite3WalkExprList(Walker *pWalker, ExprList *p){ |
+ int i; |
+ struct ExprList_item *pItem; |
+ if( p ){ |
+ for(i=p->nExpr, pItem=p->a; i>0; i--, pItem++){ |
+ if( sqlite3WalkExpr(pWalker, pItem->pExpr) ) return WRC_Abort; |
+ } |
+ } |
+ return WRC_Continue; |
+} |
+ |
+/* |
+** Walk all expressions associated with SELECT statement p. Do |
+** not invoke the SELECT callback on p, but do (of course) invoke |
+** any expr callbacks and SELECT callbacks that come from subqueries. |
+** Return WRC_Abort or WRC_Continue. |
+*/ |
+int sqlite3WalkSelectExpr(Walker *pWalker, Select *p){ |
+ if( sqlite3WalkExprList(pWalker, p->pEList) ) return WRC_Abort; |
+ if( sqlite3WalkExpr(pWalker, p->pWhere) ) return WRC_Abort; |
+ if( sqlite3WalkExprList(pWalker, p->pGroupBy) ) return WRC_Abort; |
+ if( sqlite3WalkExpr(pWalker, p->pHaving) ) return WRC_Abort; |
+ if( sqlite3WalkExprList(pWalker, p->pOrderBy) ) return WRC_Abort; |
+ if( sqlite3WalkExpr(pWalker, p->pLimit) ) return WRC_Abort; |
+ if( sqlite3WalkExpr(pWalker, p->pOffset) ) return WRC_Abort; |
+ return WRC_Continue; |
+} |
+ |
+/* |
+** Walk the parse trees associated with all subqueries in the |
+** FROM clause of SELECT statement p. Do not invoke the select |
+** callback on p, but do invoke it on each FROM clause subquery |
+** and on any subqueries further down in the tree. Return |
+** WRC_Abort or WRC_Continue; |
+*/ |
+int sqlite3WalkSelectFrom(Walker *pWalker, Select *p){ |
+ SrcList *pSrc; |
+ int i; |
+ struct SrcList_item *pItem; |
+ |
+ pSrc = p->pSrc; |
+ if( ALWAYS(pSrc) ){ |
+ for(i=pSrc->nSrc, pItem=pSrc->a; i>0; i--, pItem++){ |
+ if( sqlite3WalkSelect(pWalker, pItem->pSelect) ){ |
+ return WRC_Abort; |
+ } |
+ } |
+ } |
+ return WRC_Continue; |
+} |
+ |
+/* |
+** Call sqlite3WalkExpr() for every expression in Select statement p. |
+** Invoke sqlite3WalkSelect() for subqueries in the FROM clause and |
+** on the compound select chain, p->pPrior. |
+** |
+** Return WRC_Continue under normal conditions. Return WRC_Abort if |
+** there is an abort request. |
+** |
+** If the Walker does not have an xSelectCallback() then this routine |
+** is a no-op returning WRC_Continue. |
+*/ |
+int sqlite3WalkSelect(Walker *pWalker, Select *p){ |
+ int rc; |
+ if( p==0 || pWalker->xSelectCallback==0 ) return WRC_Continue; |
+ rc = WRC_Continue; |
+ while( p ){ |
+ rc = pWalker->xSelectCallback(pWalker, p); |
+ if( rc ) break; |
+ if( sqlite3WalkSelectExpr(pWalker, p) ) return WRC_Abort; |
+ if( sqlite3WalkSelectFrom(pWalker, p) ) return WRC_Abort; |
+ p = p->pPrior; |
+ } |
+ return rc & WRC_Abort; |
+} |