diff options
Diffstat (limited to 'var.c')
| -rw-r--r-- | var.c | 83 |
1 files changed, 83 insertions, 0 deletions
@@ -145,6 +145,88 @@ finalize_it: } +/* This function is used to prepare two var_t objects for a common operation, + * e.g before they are added, multiplied or compared. The function looks at + * the data types of both operands and finds the best data type suitable for + * the operation (in respect to current types). Then, it converts those + * operands that need conversion. Please note that the passed-in var objects + * *are* modified and returned as new type. So do call this function only if + * you actually need the conversion. + * + * This is how the common data type is selected. Note that op1 and op2 are + * just the two operands, their order is irrelevant (this would just take up + * more table space - so string/number is the same thing as number/string). + * + * Common Types: + * op1 op2 operation data type + * string string string + * string number number if op1 can be converted to number, string else + * date string date if op1 can be converted to date, string else + * number number number + * date number string (maybe we can do better?) + * date date date + * none n/a error + * + * If a boolean value is required, we need to have a number inside the + * operand. If it is not, conversion rules to number apply. Once we + * have a number, things get easy: 0 is false, anything else is true. + * Please note that due to this conversion rules, "0" becomes false + * while "-4712" becomes true. Using a date as boolen is not a good + * idea. Depending on the ultimate conversion rules, it may always + * become true or false. As such, using dates as booleans is + * prohibited and the result defined to be undefined. + * + * rgerhards, 2008-02-22 + */ +static rsRetVal +ConvForOperation(var_t *pThis, var_t *pOther) +{ + DEFiRet; + varType_t commonType; + + if(pThis->varType == VARTYPE_NONE || pOther->varType == VARTYPE_NONE) + ABORT_FINALIZE(RS_RET_INVALID_VAR); + + switch(pThis->varType) { + case VARTYPE_NONE: + ABORT_FINALIZE(RS_RET_INVALID_VAR); + break; + // TODO: remove VARTYPE_PSZ? + // TODO: check need for SHORT/INT/LONG... + case VARTYPE_PSZ: + case VARTYPE_CSTR: + switch(pThis->varType) { + case VARTYPE_NONE: + ABORT_FINALIZE(RS_RET_INVALID_VAR); + break; + case VARTYPE_PSZ: + case VARTYPE_CSTR: + break; + case VARTYPE_SHORT: + case VARTYPE_INT: + case VARTYPE_LONG: + case VARTYPE_INT64: + break; + case VARTYPE_SYSLOGTIME: + ABORT_FINALIZE(RS_RET_NOT_IMPLEMENTED); + break; + } + break; + case VARTYPE_SHORT: + case VARTYPE_INT: + case VARTYPE_LONG: + case VARTYPE_INT64: + break; + case VARTYPE_SYSLOGTIME: + ABORT_FINALIZE(RS_RET_NOT_IMPLEMENTED); + break; + } + +finalize_it: + RETiRet; +} + + /* queryInterface function * rgerhards, 2008-02-21 */ @@ -167,6 +249,7 @@ CODESTARTobjQueryInterface(var) pIf->DebugPrint = varDebugPrint; pIf->SetInt64 = varSetInt64; pIf->SetString = varSetString; + pIf->ConvForOperation = ConvForOperation; finalize_it: ENDobjQueryInterface(var) |