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Diffstat (limited to 'expr.c')
| -rw-r--r-- | expr.c | 418 |
1 files changed, 0 insertions, 418 deletions
diff --git a/expr.c b/expr.c deleted file mode 100644 index 736b9d14..00000000 --- a/expr.c +++ /dev/null @@ -1,418 +0,0 @@ -/* expr.c - an expression class. - * This module contains all code needed to represent expressions. Most - * importantly, that means code to parse and execute them. Expressions - * heavily depend on (loadable) functions, so it works in conjunction - * with the function manager. - * - * Module begun 2007-11-30 by Rainer Gerhards - * - * Copyright 2007, 2008 Rainer Gerhards and Adiscon GmbH. - * - * This file is part of the rsyslog runtime library. - * - * The rsyslog runtime library is free software: you can redistribute it and/or modify - * it under the terms of the GNU Lesser General Public License as published by - * the Free Software Foundation, either version 3 of the License, or - * (at your option) any later version. - * - * The rsyslog runtime library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public License - * along with the rsyslog runtime library. If not, see <http://www.gnu.org/licenses/>. - * - * A copy of the GPL can be found in the file "COPYING" in this distribution. - * A copy of the LGPL can be found in the file "COPYING.LESSER" in this distribution. - */ - -#include "config.h" -#include <stdlib.h> -#include <assert.h> - -#include "rsyslog.h" -#include "template.h" -#include "expr.h" - -/* static data */ -DEFobjStaticHelpers -DEFobjCurrIf(vmprg) -DEFobjCurrIf(var) -DEFobjCurrIf(ctok_token) -DEFobjCurrIf(ctok) - - -/* ------------------------------ parser functions ------------------------------ */ -/* the following functions implement the parser. They are all static. For - * simplicity, the function names match their ABNF definition. The ABNF is defined - * in the doc set. See file expression.html for details. I do *not* reproduce it - * here in an effort to keep both files in sync. - * - * All functions receive the current expression object as parameter as well as the - * current tokenizer. - * - * rgerhards, 2008-02-19 - */ - -/* forward definiton - thanks to recursive ABNF, we can not avoid at least one ;) */ -static rsRetVal expr(expr_t *pThis, ctok_t *tok); - - -static rsRetVal -terminal(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - ctok_token_t *pToken = NULL; - var_t *pVar; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - CHKiRet(ctok.GetToken(tok, &pToken)); - /* note: pToken is destructed in finalize_it */ - - switch(pToken->tok) { - case ctok_SIMPSTR: - dbgoprint((obj_t*) pThis, "simpstr\n"); - CHKiRet(ctok_token.UnlinkVar(pToken, &pVar)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_PUSHCONSTANT, pVar)); /* add to program */ - break; - case ctok_NUMBER: - dbgoprint((obj_t*) pThis, "number\n"); - CHKiRet(ctok_token.UnlinkVar(pToken, &pVar)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_PUSHCONSTANT, pVar)); /* add to program */ - break; - case ctok_FUNCTION: - dbgoprint((obj_t*) pThis, "function\n"); - // vm: call - well, need to implement that first - ABORT_FINALIZE(RS_RET_NOT_IMPLEMENTED); - break; - case ctok_MSGVAR: - dbgoprint((obj_t*) pThis, "MSGVAR\n"); - CHKiRet(ctok_token.UnlinkVar(pToken, &pVar)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_PUSHMSGVAR, pVar)); /* add to program */ - break; - case ctok_SYSVAR: - dbgoprint((obj_t*) pThis, "SYSVAR\n"); - CHKiRet(ctok_token.UnlinkVar(pToken, &pVar)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_PUSHSYSVAR, pVar)); /* add to program */ - break; - case ctok_LPAREN: - dbgoprint((obj_t*) pThis, "expr\n"); - CHKiRet(ctok_token.Destruct(&pToken)); /* "eat" processed token */ - CHKiRet(expr(pThis, tok)); - CHKiRet(ctok.GetToken(tok, &pToken)); /* get next one */ - if(pToken->tok != ctok_RPAREN) - ABORT_FINALIZE(RS_RET_SYNTAX_ERROR); - break; - default: - dbgoprint((obj_t*) pThis, "invalid token %d\n", pToken->tok); - ABORT_FINALIZE(RS_RET_SYNTAX_ERROR); - break; - } - -finalize_it: - if(pToken != NULL) { - ctok_token.Destruct(&pToken); /* "eat" processed token */ - } - - RETiRet; -} - -static rsRetVal -factor(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - ctok_token_t *pToken; - int bWasNot; - int bWasUnaryMinus; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - CHKiRet(ctok.GetToken(tok, &pToken)); - if(pToken->tok == ctok_NOT) { - dbgprintf("not\n"); - bWasNot = 1; - CHKiRet(ctok_token.Destruct(&pToken)); /* no longer needed */ - CHKiRet(ctok.GetToken(tok, &pToken)); /* get new one for next check */ - } else { - bWasNot = 0; - } - - if(pToken->tok == ctok_MINUS) { - dbgprintf("unary minus\n"); - bWasUnaryMinus = 1; - CHKiRet(ctok_token.Destruct(&pToken)); /* no longer needed */ - } else { - bWasUnaryMinus = 0; - /* we could not process the token, so push it back */ - CHKiRet(ctok.UngetToken(tok, pToken)); - } - - CHKiRet(terminal(pThis, tok)); - - /* warning: the order if the two following ifs is important. Do not change them, this - * would change the semantics of the expression! - */ - if(bWasUnaryMinus) { - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_UNARY_MINUS, NULL)); /* add to program */ - } - - if(bWasNot == 1) { - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_NOT, NULL)); /* add to program */ - } - -finalize_it: - RETiRet; -} - - -static rsRetVal -term(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - ctok_token_t *pToken; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - CHKiRet(factor(pThis, tok)); - - /* *(("*" / "/" / "%") factor) part */ - CHKiRet(ctok.GetToken(tok, &pToken)); - while(pToken->tok == ctok_TIMES || pToken->tok == ctok_DIV || pToken->tok == ctok_MOD) { - dbgoprint((obj_t*) pThis, "/,*,%%\n"); - CHKiRet(factor(pThis, tok)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, (opcode_t) pToken->tok, NULL)); /* add to program */ - CHKiRet(ctok_token.Destruct(&pToken)); /* no longer needed */ - CHKiRet(ctok.GetToken(tok, &pToken)); - } - - /* unget the token that made us exit the loop - it's obviously not one - * we can process. - */ - CHKiRet(ctok.UngetToken(tok, pToken)); - -finalize_it: - RETiRet; -} - -static rsRetVal -val(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - ctok_token_t *pToken; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - CHKiRet(term(pThis, tok)); - - /* *(("+" / "-") term) part */ - CHKiRet(ctok.GetToken(tok, &pToken)); - while(pToken->tok == ctok_PLUS || pToken->tok == ctok_MINUS || pToken->tok == ctok_STRADD) { - dbgoprint((obj_t*) pThis, "+/-/&\n"); - CHKiRet(term(pThis, tok)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, (opcode_t) pToken->tok, NULL)); /* add to program */ - CHKiRet(ctok_token.Destruct(&pToken)); /* no longer needed */ - CHKiRet(ctok.GetToken(tok, &pToken)); - } - - /* unget the token that made us exit the loop - it's obviously not one - * we can process. - */ - CHKiRet(ctok.UngetToken(tok, pToken)); - -finalize_it: - RETiRet; -} - - -static rsRetVal -e_cmp(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - ctok_token_t *pToken; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - CHKiRet(val(pThis, tok)); - - /* 0*1(cmp_op val) part */ - CHKiRet(ctok.GetToken(tok, &pToken)); - if(ctok_token.IsCmpOp(pToken)) { - dbgoprint((obj_t*) pThis, "cmp\n"); - CHKiRet(val(pThis, tok)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, (opcode_t) pToken->tok, NULL)); /* add to program */ - CHKiRet(ctok_token.Destruct(&pToken)); /* no longer needed */ - } else { - /* we could not process the token, so push it back */ - CHKiRet(ctok.UngetToken(tok, pToken)); - } - - -finalize_it: - RETiRet; -} - - -static rsRetVal -e_and(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - ctok_token_t *pToken; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - CHKiRet(e_cmp(pThis, tok)); - - /* *("and" e_cmp) part */ - CHKiRet(ctok.GetToken(tok, &pToken)); - while(pToken->tok == ctok_AND) { - dbgoprint((obj_t*) pThis, "and\n"); - CHKiRet(e_cmp(pThis, tok)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_AND, NULL)); /* add to program */ - CHKiRet(ctok_token.Destruct(&pToken)); /* no longer needed */ - CHKiRet(ctok.GetToken(tok, &pToken)); - } - - /* unget the token that made us exit the loop - it's obviously not one - * we can process. - */ - CHKiRet(ctok.UngetToken(tok, pToken)); - -finalize_it: - RETiRet; -} - - -static rsRetVal -expr(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - ctok_token_t *pToken; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - CHKiRet(e_and(pThis, tok)); - - /* *("or" e_and) part */ - CHKiRet(ctok.GetToken(tok, &pToken)); - while(pToken->tok == ctok_OR) { - dbgoprint((obj_t*) pThis, "found OR\n"); - CHKiRet(e_and(pThis, tok)); - CHKiRet(vmprg.AddVarOperation(pThis->pVmprg, opcode_OR, NULL)); /* add to program */ - CHKiRet(ctok_token.Destruct(&pToken)); /* no longer needed */ - CHKiRet(ctok.GetToken(tok, &pToken)); - } - - /* unget the token that made us exit the loop - it's obviously not one - * we can process. - */ - CHKiRet(ctok.UngetToken(tok, pToken)); - -finalize_it: - RETiRet; -} - - -/* ------------------------------ end parser functions ------------------------------ */ - - -/* ------------------------------ actual expr object functions ------------------------------ */ - -/* Standard-Constructor - * rgerhards, 2008-02-09 (a rainy Tenerife return flight day ;)) - */ -BEGINobjConstruct(expr) /* be sure to specify the object type also in END macro! */ -ENDobjConstruct(expr) - - -/* ConstructionFinalizer - * rgerhards, 2008-01-09 - */ -rsRetVal exprConstructFinalize(expr_t __attribute__((unused)) *pThis) -{ - DEFiRet; - - ISOBJ_TYPE_assert(pThis, expr); - - RETiRet; -} - - -/* destructor for the expr object */ -BEGINobjDestruct(expr) /* be sure to specify the object type also in END and CODESTART macros! */ -CODESTARTobjDestruct(expr) - if(pThis->pVmprg != NULL) - vmprg.Destruct(&pThis->pVmprg); -ENDobjDestruct(expr) - - -/* parse an expression object based on a given tokenizer - * rgerhards, 2008-02-19 - */ -rsRetVal -exprParse(expr_t *pThis, ctok_t *tok) -{ - DEFiRet; - - ISOBJ_TYPE_assert(pThis, expr); - ISOBJ_TYPE_assert(tok, ctok); - - /* first, we need to make sure we have a program where we can add to what we parse... */ - CHKiRet(vmprg.Construct(&pThis->pVmprg)); - CHKiRet(vmprg.ConstructFinalize(pThis->pVmprg)); - - /* happy parsing... */ - CHKiRet(expr(pThis, tok)); - dbgoprint((obj_t*) pThis, "successfully parsed/created expression\n"); - -finalize_it: - RETiRet; -} - - -/* queryInterface function - * rgerhards, 2008-02-21 - */ -BEGINobjQueryInterface(expr) -CODESTARTobjQueryInterface(expr) - if(pIf->ifVersion != exprCURR_IF_VERSION) { /* check for current version, increment on each change */ - ABORT_FINALIZE(RS_RET_INTERFACE_NOT_SUPPORTED); - } - - /* ok, we have the right interface, so let's fill it - * Please note that we may also do some backwards-compatibility - * work here (if we can support an older interface version - that, - * of course, also affects the "if" above). - */ - pIf->Construct = exprConstruct; - pIf->ConstructFinalize = exprConstructFinalize; - pIf->Destruct = exprDestruct; - pIf->Parse = exprParse; -finalize_it: -ENDobjQueryInterface(expr) - - -/* Initialize the expr class. Must be called as the very first method - * before anything else is called inside this class. - * rgerhards, 2008-02-19 - */ -BEGINObjClassInit(expr, 1, OBJ_IS_CORE_MODULE) /* class, version */ - /* request objects we use */ - CHKiRet(objUse(vmprg, CORE_COMPONENT)); - CHKiRet(objUse(var, CORE_COMPONENT)); - CHKiRet(objUse(ctok_token, CORE_COMPONENT)); - CHKiRet(objUse(ctok, CORE_COMPONENT)); - - OBJSetMethodHandler(objMethod_CONSTRUCTION_FINALIZER, exprConstructFinalize); -ENDObjClassInit(expr) - -/* vi:set ai: - */ |