summaryrefslogtreecommitdiff
path: root/rdf/base/rdfTriplesSerializer.cpp
blob: f419c7612f45d6defe4d75e0db71a97db65d1c36 (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
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsIOutputStream.h"
#include "nsReadableUtils.h"
#include "nsCRT.h"
#include "nsCOMPtr.h"
#include "nsString.h"
#include "nsPrintfCString.h"
#include "nsIBufferedStreams.h"
#include "nsNetCID.h"
#include "nsComponentManagerUtils.h"

#include "rdfISerializer.h"
#include "rdfIDataSource.h"
#include "rdfITripleVisitor.h"

#include "nsIRDFResource.h"
#include "nsIRDFLiteral.h"
#include "mozilla/Attributes.h"

class TriplesVisitor final : public rdfITripleVisitor
{
public:
    explicit TriplesVisitor(nsIOutputStream* aOut) : mOut(aOut) {}
    NS_DECL_RDFITRIPLEVISITOR
    NS_DECL_ISUPPORTS
protected:
    ~TriplesVisitor() {}
    nsresult writeResource(nsIRDFResource* aResource);
    nsIOutputStream* mOut;
};

NS_IMPL_ISUPPORTS(TriplesVisitor, rdfITripleVisitor)

nsresult
TriplesVisitor::writeResource(nsIRDFResource *aResource)
{
    nsCString res;
    uint32_t writeCount, wroteCount;
    mOut->Write("<", 1, &wroteCount);
    NS_ENSURE_TRUE(wroteCount == 1, NS_ERROR_FAILURE);
    nsresult rv = aResource->GetValueUTF8(res);
    NS_ENSURE_SUCCESS(rv, rv);
    writeCount = res.Length();
    mOut->Write(res.get(), writeCount, &wroteCount);
    NS_ENSURE_TRUE(writeCount == wroteCount, NS_ERROR_FAILURE);
    mOut->Write("> ", 2, &wroteCount);
    NS_ENSURE_TRUE(wroteCount == 2, NS_ERROR_FAILURE);
    return NS_OK;
}

NS_IMETHODIMP
TriplesVisitor::Visit(nsIRDFNode *aSubject, nsIRDFResource *aPredicate,
                      nsIRDFNode *aObject, bool aTruthValue)
{
    nsCOMPtr<nsIRDFResource> subjectRes = do_QueryInterface(aSubject);
    nsresult rv = NS_OK;
    if (subjectRes) {
        rv = writeResource(subjectRes);
    }
    if (NS_FAILED(rv)) {
        return rv;
    }
    rv = writeResource(aPredicate);
    if (NS_FAILED(rv)) {
        return rv;
    }
    nsCOMPtr<nsIRDFResource> res = do_QueryInterface(aObject);
    nsCOMPtr<nsIRDFLiteral> lit;
    nsCOMPtr<nsIRDFInt> intLit;
    uint32_t wroteCount;
    if (res) {
        rv = writeResource(res);
    } else if ((lit = do_QueryInterface(aObject)) != nullptr) {
        const char16_t *value;
        lit->GetValueConst(&value);
        nsAutoCString object;
        object.Append('"');
        AppendUTF16toUTF8(value, object);
        object.AppendLiteral("\" ");
        uint32_t writeCount = object.Length();
        rv = mOut->Write(object.get(), writeCount, &wroteCount);
        NS_ENSURE_TRUE(writeCount == wroteCount, NS_ERROR_FAILURE);
    } else if ((intLit = do_QueryInterface(aObject)) != nullptr) {
        int32_t value;
        intLit->GetValue(&value);
        nsPrintfCString
            object("\"%i\"^^<http://www.w3.org/2001/XMLSchema#integer> ",
                   value);
        uint32_t writeCount = object.Length();
        rv = mOut->Write(object.get(), writeCount, &wroteCount);
        NS_ENSURE_TRUE(writeCount == wroteCount, NS_ERROR_FAILURE);
    }
    NS_ENSURE_SUCCESS(rv, rv);
    return mOut->Write(".\n", 2, &wroteCount);
}

class rdfTriplesSerializer final : public rdfISerializer
{
public:
  NS_DECL_ISUPPORTS
  NS_DECL_RDFISERIALIZER

  rdfTriplesSerializer();

private:
  ~rdfTriplesSerializer();

};

nsresult
NS_NewTriplesSerializer(rdfISerializer** aResult)
{
    NS_PRECONDITION(aResult != nullptr, "null ptr");
    if (! aResult)
        return NS_ERROR_NULL_POINTER;

    *aResult = new rdfTriplesSerializer();
    if (! *aResult)
        return NS_ERROR_OUT_OF_MEMORY;
    NS_ADDREF(*aResult);
    return NS_OK;
}

NS_IMPL_ISUPPORTS(rdfTriplesSerializer, rdfISerializer)

rdfTriplesSerializer::rdfTriplesSerializer()
{
}

rdfTriplesSerializer::~rdfTriplesSerializer()
{
}

NS_IMETHODIMP
rdfTriplesSerializer::Serialize(rdfIDataSource *aDataSource,
                                nsIOutputStream *aOut)
{
    nsresult rv;
    nsCOMPtr<nsIBufferedOutputStream> bufout = 
        do_CreateInstance(NS_BUFFEREDOUTPUTSTREAM_CONTRACTID, &rv);
    NS_ENSURE_SUCCESS(rv, rv);
    rv = bufout->Init(aOut, 1024);
    NS_ENSURE_SUCCESS(rv, rv);
    nsCOMPtr<rdfITripleVisitor> tv = new TriplesVisitor(bufout);
    NS_ENSURE_TRUE(tv, NS_ERROR_OUT_OF_MEMORY);
    return aDataSource->VisitAllTriples(tv);
}