Files
pvAccess/pvAccessApp/factory/CreateRequestFactory.cpp
2012-06-15 14:47:16 +02:00

233 lines
8.5 KiB
C++

/**
* Copyright - See the COPYRIGHT that is included with this distribution.
* pvAccessCPP is distributed subject to a Software License Agreement found
* in file LICENSE that is included with this distribution.
*/
#include <string>
#include <sstream>
#include <pv/pvData.h>
#include <pv/lock.h>
#include <pv/pvAccess.h>
using namespace epics::pvData;
namespace epics {
namespace pvAccess {
class CreateRequestImpl : public CreateRequest {
private:
static void trim(std::string& str)
{
std::string::size_type pos = str.find_last_not_of(' ');
if(pos != std::string::npos) {
str.erase(pos + 1);
pos = str.find_first_not_of(' ');
if(pos != std::string::npos) str.erase(0, pos);
}
else str.erase(str.begin(), str.end());
}
static size_t findMatchingBrace(std::string& request, int index, int numOpen) {
size_t openBrace = request.find('{', index+1);
size_t closeBrace = request.find('}', index+1);
if(openBrace == std::string::npos && closeBrace == std::string::npos) return std::string::npos;
if (openBrace != std::string::npos) {
if(openBrace<closeBrace) return findMatchingBrace(request,openBrace,numOpen+1);
if(numOpen==1) return closeBrace;
return findMatchingBrace(request,closeBrace,numOpen-1);
}
if(numOpen==1) return closeBrace;
return findMatchingBrace(request,closeBrace,numOpen-1);
}
static void createFieldRequest(PVStructurePtr const & pvParent,std::string request,bool fieldListOK) {
trim(request);
if(request.length()<=0) return;
size_t comma = request.find(',');
size_t openBrace = request.find('{');
size_t openBracket = request.find('[');
if(openBrace != std::string::npos || openBracket != std::string::npos) fieldListOK = false;
if(openBrace != std::string::npos && (comma==std::string::npos || comma>openBrace)) {
//find matching brace
size_t closeBrace = findMatchingBrace(request,openBrace+1,1);
if(closeBrace==std::string::npos) {
THROW_BASE_EXCEPTION("mismatched { }");
}
String fieldName = request.substr(0,openBrace);
PVFieldPtrArray fields;
StringArray fieldNames;
PVStructurePtr pvStructure(getPVDataCreate()->createPVStructure(fieldNames, fields));
createFieldRequest(pvStructure,request.substr(openBrace+1,closeBrace-openBrace-1),false);
pvParent->appendPVField(fieldName, pvStructure);
if(request.length()>closeBrace+1) {
if(request.at(closeBrace+1) != ',') {
THROW_BASE_EXCEPTION("misssing , after }");
}
createFieldRequest(pvParent,request.substr(closeBrace+2),false);
}
return;
}
if(openBracket==std::string::npos && fieldListOK) {
PVStringPtr pvStringField(std::tr1::static_pointer_cast<PVString>(getPVDataCreate()->createPVScalar(pvString)));
pvStringField->put(request);
pvParent->appendPVField("fieldList", pvStringField);
return;
}
if(openBracket!=std::string::npos && (comma==std::string::npos || comma>openBracket)) {
size_t closeBracket = request.find(']');
if(closeBracket==std::string::npos) {
THROW_BASE_EXCEPTION("option does not have matching []");
}
createLeafFieldRequest(pvParent,request.substr(0, closeBracket+1));
size_t commaLoc = request.rfind(',');
if(commaLoc!=std::string::npos && commaLoc>closeBracket) {
int nextComma = request.find(',', closeBracket);
createFieldRequest(pvParent,request.substr(nextComma+1),false);
}
return;
}
if(comma!=std::string::npos) {
createLeafFieldRequest(pvParent,request.substr(0, comma));
createFieldRequest(pvParent,request.substr(comma+1),false);
return;
}
createLeafFieldRequest(pvParent,request);
}
static void createLeafFieldRequest(PVStructurePtr const & pvParent,String request) {
size_t openBracket = request.find('[');
String fullName = request;
if(openBracket != std::string::npos) fullName = request.substr(0,openBracket);
size_t indLast = fullName.rfind('.');
String fieldName = fullName;
if(indLast>1 && indLast != std::string::npos) fieldName = fullName.substr(indLast+1);
PVFieldPtrArray fields;
StringArray fieldNames;
PVStructurePtr pvStructure(getPVDataCreate()->createPVStructure(fieldNames, fields));
PVStructurePtr pvLeaf(getPVDataCreate()->createPVStructure(fieldNames, fields));
PVStringPtr pvStringField(std::tr1::static_pointer_cast<PVString>(getPVDataCreate()->createPVScalar(pvString)));
pvStringField->put(fullName);
pvLeaf->appendPVField("source", pvStringField);
if(openBracket != std::string::npos) {
size_t closeBracket = request.find(']');
if(closeBracket==std::string::npos) {
THROW_BASE_EXCEPTION("option does not have matching []");
}
createRequestOptions(pvLeaf,request.substr(openBracket+1, closeBracket-openBracket-1));
}
pvStructure->appendPVField("leaf", pvLeaf);
pvParent->appendPVField("fieldName", pvStructure);
}
static void createRequestOptions(PVStructurePtr const & pvParent,std::string request) {
trim(request);
if(request.length()<=1) return;
std::string token;
std::istringstream iss(request);
while (getline(iss, token, ','))
{
size_t equalsPos = token.find('=');
size_t equalsRPos = token.rfind('=');
if (equalsPos != equalsRPos)
{
THROW_BASE_EXCEPTION("illegal option");
}
if (equalsPos != std::string::npos)
{
PVStringPtr pvStringField(std::tr1::static_pointer_cast<PVString>(getPVDataCreate()->createPVScalar(pvString)));
pvStringField->put(token.substr(equalsPos+1));
pvParent->appendPVField(token.substr(0, equalsPos), pvStringField);
}
}
}
public:
virtual PVStructure::shared_pointer createRequest(String request)
{
static PVFieldPtrArray emptyFields;
static StringArray emptyFieldNames;
if (!request.empty()) trim(request);
if (request.empty())
{
PVStructure::shared_pointer pvStructure(getPVDataCreate()->createPVStructure(emptyFieldNames, emptyFields));
return pvStructure;
}
size_t offsetRecord = request.find("record[");
size_t offsetField = request.find("field(");
size_t offsetPutField = request.find("putField(");
size_t offsetGetField = request.find("getField(");
PVStructure::shared_pointer pvStructure(getPVDataCreate()->createPVStructure(emptyFieldNames, emptyFields));
if (offsetRecord != std::string::npos) {
size_t offsetBegin = request.find('[', offsetRecord);
size_t offsetEnd = request.find(']', offsetBegin);
if(offsetEnd == std::string::npos) {
THROW_BASE_EXCEPTION("record[ does not have matching ]");
}
PVStructure::shared_pointer pvStruct(getPVDataCreate()->createPVStructure(emptyFieldNames, emptyFields));
createRequestOptions(pvStruct,request.substr(offsetBegin+1, offsetEnd-offsetBegin-1));
pvStructure->appendPVField("record", pvStruct);
}
if (offsetField != std::string::npos) {
size_t offsetBegin = request.find('(', offsetField);
size_t offsetEnd = request.find(')', offsetBegin);
if(offsetEnd == std::string::npos) {
THROW_BASE_EXCEPTION("field( does not have matching )");
}
PVStructure::shared_pointer pvStruct(getPVDataCreate()->createPVStructure(emptyFieldNames, emptyFields));
createFieldRequest(pvStruct,request.substr(offsetBegin+1, offsetEnd-offsetBegin-1),true);
pvStructure->appendPVField("field", pvStruct);
}
if (offsetPutField != std::string::npos) {
size_t offsetBegin = request.find('(', offsetPutField);
size_t offsetEnd = request.find(')', offsetBegin);
if(offsetEnd == std::string::npos) {
THROW_BASE_EXCEPTION("putField( does not have matching )");
}
PVStructure::shared_pointer pvStruct(getPVDataCreate()->createPVStructure(emptyFieldNames, emptyFields));
createFieldRequest(pvStruct,request.substr(offsetBegin+1, offsetEnd-offsetBegin-1),true);
pvStructure->appendPVField("putField", pvStruct);
}
if (offsetGetField != std::string::npos) {
size_t offsetBegin = request.find('(', offsetGetField);
size_t offsetEnd = request.find(')', offsetBegin);
if(offsetEnd == std::string::npos) {
THROW_BASE_EXCEPTION("getField( does not have matching )");
}
PVStructure::shared_pointer pvStruct(getPVDataCreate()->createPVStructure(emptyFieldNames, emptyFields));
createFieldRequest(pvStruct,request.substr(offsetBegin+1, offsetEnd-offsetBegin-1),true);
pvStructure->appendPVField("getField", pvStruct);
}
if (pvStructure.get()->getStructure()->getNumberFields()==0) {
createFieldRequest(pvStructure,request,true);
}
return pvStructure;
}
};
CreateRequest::shared_pointer createRequest;
CreateRequest::shared_pointer getCreateRequest() {
static Mutex mutex;
Lock guard(mutex);
if(createRequest.get()==0){
createRequest.reset(new CreateRequestImpl());
}
return createRequest;
}
}}