summaryrefslogtreecommitdiffstats
path: root/external_libs/cpp/yaml-cpp/src/parser.cpp
blob: b836823f9a89759176996e744a1649486a193a16 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
#include "yaml-cpp/parser.h"
#include "yaml-cpp/eventhandler.h"
#include "yaml-cpp/exceptions.h"
#include "yaml-cpp/node.h"
#include "directives.h"
#include "nodebuilder.h"
#include "scanner.h"
#include "singledocparser.h"
#include "tag.h"
#include "token.h"
#include <sstream>
#include <cstdio>

namespace YAML
{
	Parser::Parser()
	{
	}
	
	Parser::Parser(std::istream& in)
	{
		Load(in);
	}

	Parser::~Parser()
	{
	}

	Parser::operator bool() const
	{
		return m_pScanner.get() && !m_pScanner->empty();
	}

	void Parser::Load(std::istream& in)
	{
		m_pScanner.reset(new Scanner(in));
		m_pDirectives.reset(new Directives);
	}

	// HandleNextDocument
	// . Handles the next document
	// . Throws a ParserException on error.
	// . Returns false if there are no more documents
	bool Parser::HandleNextDocument(EventHandler& eventHandler)
	{
		if(!m_pScanner.get())
			return false;

		ParseDirectives();
		if(m_pScanner->empty())
			return false;
		
		SingleDocParser sdp(*m_pScanner, *m_pDirectives);
		sdp.HandleDocument(eventHandler);
		return true;
	}

	// GetNextDocument
	// . Reads the next document in the queue (of tokens).
	// . Throws a ParserException on error.
	bool Parser::GetNextDocument(Node& document)
	{
		NodeBuilder builder(document);
		return HandleNextDocument(builder);
	}

	// ParseDirectives
	// . Reads any directives that are next in the queue.
	void Parser::ParseDirectives()
	{
		bool readDirective = false;

		while(1) {
			if(m_pScanner->empty())
				break;

			Token& token = m_pScanner->peek();
			if(token.type != Token::DIRECTIVE)
				break;

			// we keep the directives from the last document if none are specified;
			// but if any directives are specific, then we reset them
			if(!readDirective)
				m_pDirectives.reset(new Directives);

			readDirective = true;
			HandleDirective(token);
			m_pScanner->pop();
		}
	}

	void Parser::HandleDirective(const Token& token)
	{
		if(token.value == "YAML")
			HandleYamlDirective(token);
		else if(token.value == "TAG")
			HandleTagDirective(token);
	}

	// HandleYamlDirective
	// . Should be of the form 'major.minor' (like a version number)
	void Parser::HandleYamlDirective(const Token& token)
	{
		if(token.params.size() != 1)
			throw ParserException(token.mark, ErrorMsg::YAML_DIRECTIVE_ARGS);
		
		if(!m_pDirectives->version.isDefault)
			throw ParserException(token.mark, ErrorMsg::REPEATED_YAML_DIRECTIVE);

		std::stringstream str(token.params[0]);
		str >> m_pDirectives->version.major;
		str.get();
		str >> m_pDirectives->version.minor;
		if(!str || str.peek() != EOF)
			throw ParserException(token.mark, std::string(ErrorMsg::YAML_VERSION) + token.params[0]);

		if(m_pDirectives->version.major > 1)
			throw ParserException(token.mark, ErrorMsg::YAML_MAJOR_VERSION);

		m_pDirectives->version.isDefault = false;
		// TODO: warning on major == 1, minor > 2?
	}

	// HandleTagDirective
	// . Should be of the form 'handle prefix', where 'handle' is converted to 'prefix' in the file.
	void Parser::HandleTagDirective(const Token& token)
	{
		if(token.params.size() != 2)
			throw ParserException(token.mark, ErrorMsg::TAG_DIRECTIVE_ARGS);

		const std::string& handle = token.params[0];
		const std::string& prefix = token.params[1];
		if(m_pDirectives->tags.find(handle) != m_pDirectives->tags.end())
			throw ParserException(token.mark, ErrorMsg::REPEATED_TAG_DIRECTIVE);
		
		m_pDirectives->tags[handle] = prefix;
	}

	void Parser::PrintTokens(std::ostream& out)
	{
		if(!m_pScanner.get())
			return;
		
		while(1) {
			if(m_pScanner->empty())
				break;

			out << m_pScanner->peek() << "\n";
			m_pScanner->pop();
		}
	}
}