gremlin/libs/yaml-cpp/src/node.cpp

304 lines
6.6 KiB
C++

#include "node.h"
#include "token.h"
#include "scanner.h"
#include "content.h"
#include "parser.h"
#include "scalar.h"
#include "sequence.h"
#include "map.h"
#include "aliascontent.h"
#include "iterpriv.h"
#include "emitter.h"
#include "tag.h"
#include <stdexcept>
namespace YAML
{
// the ordering!
bool ltnode::operator ()(const Node *pNode1, const Node *pNode2) const
{
return *pNode1 < *pNode2;
}
Node::Node(): m_pContent(0), m_alias(false), m_pIdentity(this), m_referenced(true)
{
}
Node::Node(const Mark& mark, const std::string& anchor, const std::string& tag, const Content *pContent)
: m_mark(mark), m_anchor(anchor), m_tag(tag), m_pContent(0), m_alias(false), m_pIdentity(this), m_referenced(false)
{
if(pContent)
m_pContent = pContent->Clone();
}
Node::~Node()
{
Clear();
}
void Node::Clear()
{
delete m_pContent;
m_pContent = 0;
m_alias = false;
m_referenced = false;
m_anchor.clear();
m_tag.clear();
}
std::auto_ptr<Node> Node::Clone() const
{
if(m_alias)
throw std::runtime_error("yaml-cpp: Can't clone alias"); // TODO: what to do about aliases?
return std::auto_ptr<Node> (new Node(m_mark, m_anchor, m_tag, m_pContent));
}
void Node::Parse(Scanner *pScanner, ParserState& state)
{
Clear();
// an empty node *is* a possibility
if(pScanner->empty())
return;
// save location
m_mark = pScanner->peek().mark;
// special case: a value node by itself must be a map, with no header
if(pScanner->peek().type == Token::VALUE) {
m_pContent = new Map;
m_pContent->Parse(pScanner, state);
return;
}
ParseHeader(pScanner, state);
// is this an alias? if so, its contents are an alias to
// a previously defined anchor
if(m_alias) {
// the scanner throws an exception if it doesn't know this anchor name
const Node *pReferencedNode = pScanner->Retrieve(m_anchor);
m_pIdentity = pReferencedNode;
// mark the referenced node for the sake of the client code
pReferencedNode->m_referenced = true;
// use of an Alias object keeps the referenced content from
// being deleted twice
Content *pAliasedContent = pReferencedNode->m_pContent;
if(pAliasedContent)
m_pContent = new AliasContent(pAliasedContent);
return;
}
// now split based on what kind of node we should be
switch(pScanner->peek().type) {
case Token::SCALAR:
m_pContent = new Scalar;
break;
case Token::FLOW_SEQ_START:
case Token::BLOCK_SEQ_START:
m_pContent = new Sequence;
break;
case Token::FLOW_MAP_START:
case Token::BLOCK_MAP_START:
m_pContent = new Map;
break;
case Token::KEY:
// compact maps can only go in a flow sequence
if(state.GetCurCollectionType() == ParserState::FLOW_SEQ)
m_pContent = new Map;
break;
default:
break;
}
// Have to save anchor before parsing to allow for aliases as
// contained node (recursive structure)
if(!m_anchor.empty())
pScanner->Save(m_anchor, this);
if(m_pContent)
m_pContent->Parse(pScanner, state);
}
// ParseHeader
// . Grabs any tag, alias, or anchor tokens and deals with them.
void Node::ParseHeader(Scanner *pScanner, ParserState& state)
{
while(1) {
if(pScanner->empty())
return;
switch(pScanner->peek().type) {
case Token::TAG: ParseTag(pScanner, state); break;
case Token::ANCHOR: ParseAnchor(pScanner, state); break;
case Token::ALIAS: ParseAlias(pScanner, state); break;
default: return;
}
}
}
void Node::ParseTag(Scanner *pScanner, ParserState& state)
{
Token& token = pScanner->peek();
if(m_tag != "")
throw ParserException(token.mark, ErrorMsg::MULTIPLE_TAGS);
Tag tag(token);
m_tag = tag.Translate(state);
pScanner->pop();
}
void Node::ParseAnchor(Scanner *pScanner, ParserState& /*state*/)
{
Token& token = pScanner->peek();
if(m_anchor != "")
throw ParserException(token.mark, ErrorMsg::MULTIPLE_ANCHORS);
m_anchor = token.value;
m_alias = false;
pScanner->pop();
}
void Node::ParseAlias(Scanner *pScanner, ParserState& /*state*/)
{
Token& token = pScanner->peek();
if(m_anchor != "")
throw ParserException(token.mark, ErrorMsg::MULTIPLE_ALIASES);
if(m_tag != "")
throw ParserException(token.mark, ErrorMsg::ALIAS_CONTENT);
m_anchor = token.value;
m_alias = true;
pScanner->pop();
}
CONTENT_TYPE Node::GetType() const
{
if(!m_pContent)
return CT_NONE;
if(m_pContent->IsScalar())
return CT_SCALAR;
else if(m_pContent->IsSequence())
return CT_SEQUENCE;
else if(m_pContent->IsMap())
return CT_MAP;
return CT_NONE;
}
// begin
// Returns an iterator to the beginning of this (sequence or map).
Iterator Node::begin() const
{
if(!m_pContent)
return Iterator();
std::vector <Node *>::const_iterator seqIter;
if(m_pContent->GetBegin(seqIter))
return Iterator(new IterPriv(seqIter));
std::map <Node *, Node *, ltnode>::const_iterator mapIter;
if(m_pContent->GetBegin(mapIter))
return Iterator(new IterPriv(mapIter));
return Iterator();
}
// end
// . Returns an iterator to the end of this (sequence or map).
Iterator Node::end() const
{
if(!m_pContent)
return Iterator();
std::vector <Node *>::const_iterator seqIter;
if(m_pContent->GetEnd(seqIter))
return Iterator(new IterPriv(seqIter));
std::map <Node *, Node *, ltnode>::const_iterator mapIter;
if(m_pContent->GetEnd(mapIter))
return Iterator(new IterPriv(mapIter));
return Iterator();
}
// size
// . Returns the size of this node, if it's a sequence node.
// . Otherwise, returns zero.
std::size_t Node::size() const
{
if(!m_pContent)
return 0;
return m_pContent->GetSize();
}
const Node *Node::FindAtIndex(std::size_t i) const
{
if(!m_pContent)
return 0;
return m_pContent->GetNode(i);
}
bool Node::GetScalar(std::string& s) const
{
if(!m_pContent) {
if(m_tag.empty())
s = "~";
else
s = "";
return true;
}
return m_pContent->GetScalar(s);
}
Emitter& operator << (Emitter& out, const Node& node)
{
// write anchor/alias
if(node.m_anchor != "") {
if(node.m_alias)
out << Alias(node.m_anchor);
else
out << Anchor(node.m_anchor);
}
if(node.m_tag != "")
out << VerbatimTag(node.m_tag);
// write content
if(node.m_pContent)
node.m_pContent->Write(out);
else if(!node.m_alias)
out << Null;
return out;
}
int Node::Compare(const Node& rhs) const
{
// Step 1: no content is the smallest
if(!m_pContent) {
if(rhs.m_pContent)
return -1;
else
return 0;
}
if(!rhs.m_pContent)
return 1;
return m_pContent->Compare(rhs.m_pContent);
}
bool operator < (const Node& n1, const Node& n2)
{
return n1.Compare(n2) < 0;
}
}