1
2 /*
3 * Copyright 2006 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10 #include "SkXMLParser.h"
11 #include "SkChunkAlloc.h"
12 #include "SkString.h"
13 #include "SkStream.h"
14
15 #include "expat.h"
16
dupstr(SkChunkAlloc & chunk,const char src[],size_t len)17 static inline char* dupstr(SkChunkAlloc& chunk, const char src[], size_t len)
18 {
19 SkASSERT(src);
20 char* dst = (char*)chunk.alloc(len + 1, SkChunkAlloc::kThrow_AllocFailType);
21
22 memcpy(dst, src, len);
23 dst[len] = 0;
24 return dst;
25 }
26
count_pairs(const char ** p)27 static inline int count_pairs(const char** p)
28 {
29 const char** start = p;
30 while (*p)
31 {
32 SkASSERT(p[1] != NULL);
33 p += 2;
34 }
35 return (p - start) >> 1;
36 }
37
38 struct Data {
DataData39 Data() : fAlloc(2048), fState(NORMAL) {}
40
41 XML_Parser fParser;
42 SkXMLPullParser::Curr* fCurr;
43 SkChunkAlloc fAlloc;
44
45 enum State {
46 NORMAL,
47 MISSED_START_TAG,
48 RETURN_END_TAG
49 };
50 State fState;
51 const char* fEndTag; // if state is RETURN_END_TAG
52 };
53
start_proc(void * data,const char * el,const char ** attr)54 static void XMLCALL start_proc(void *data, const char *el, const char **attr)
55 {
56 Data* p = (Data*)data;
57 SkXMLPullParser::Curr* c = p->fCurr;
58 SkChunkAlloc& alloc = p->fAlloc;
59
60 c->fName = dupstr(alloc, el, strlen(el));
61
62 int n = count_pairs(attr);
63 SkXMLPullParser::AttrInfo* info = (SkXMLPullParser::AttrInfo*)alloc.alloc(n * sizeof(SkXMLPullParser::AttrInfo),
64 SkChunkAlloc::kThrow_AllocFailType);
65 c->fAttrInfoCount = n;
66 c->fAttrInfos = info;
67
68 for (int i = 0; i < n; i++)
69 {
70 info[i].fName = dupstr(alloc, attr[0], strlen(attr[0]));
71 info[i].fValue = dupstr(alloc, attr[1], strlen(attr[1]));
72 attr += 2;
73 }
74
75 c->fEventType = SkXMLPullParser::START_TAG;
76 XML_StopParser(p->fParser, true);
77 }
78
end_proc(void * data,const char * el)79 static void XMLCALL end_proc(void *data, const char *el)
80 {
81 Data* p = (Data*)data;
82 SkXMLPullParser::Curr* c = p->fCurr;
83
84 if (c->fEventType == SkXMLPullParser::START_TAG)
85 {
86 /* if we get here, we were called with a start_tag immediately
87 followed by this end_tag. The caller will only see the end_tag,
88 so we set a flag to notify them of the missed start_tag
89 */
90 p->fState = Data::MISSED_START_TAG;
91
92 SkASSERT(c->fName != NULL);
93 SkASSERT(strcmp(c->fName, el) == 0);
94 }
95 else
96 c->fName = dupstr(p->fAlloc, el, strlen(el));
97
98 c->fEventType = SkXMLPullParser::END_TAG;
99 XML_StopParser(p->fParser, true);
100 }
101
102 #include <ctype.h>
103
isws(const char s[])104 static bool isws(const char s[])
105 {
106 for (; *s; s++)
107 if (!isspace(*s))
108 return false;
109 return true;
110 }
111
text_proc(void * data,const char * text,int len)112 static void XMLCALL text_proc(void* data, const char* text, int len)
113 {
114 Data* p = (Data*)data;
115 SkXMLPullParser::Curr* c = p->fCurr;
116
117 c->fName = dupstr(p->fAlloc, text, len);
118 c->fIsWhitespace = isws(c->fName);
119
120 c->fEventType = SkXMLPullParser::TEXT;
121 XML_StopParser(p->fParser, true);
122 }
123
124 //////////////////////////////////////////////////////////////////////////
125
126 struct SkXMLPullParser::Impl {
127 Data fData;
128 void* fBuffer;
129 size_t fBufferLen;
130 };
131
reportError(XML_Parser parser)132 static void reportError(XML_Parser parser)
133 {
134 XML_Error code = XML_GetErrorCode(parser);
135 int lineNumber = XML_GetCurrentLineNumber(parser);
136 const char* msg = XML_ErrorString(code);
137
138 printf("-------- XML error [%d] on line %d, %s\n", code, lineNumber, msg);
139 }
140
onInit()141 bool SkXMLPullParser::onInit()
142 {
143 fImpl = new Impl;
144
145 XML_Parser p = XML_ParserCreate(NULL);
146 SkASSERT(p);
147
148 fImpl->fData.fParser = p;
149 fImpl->fData.fCurr = &fCurr;
150
151 XML_SetElementHandler(p, start_proc, end_proc);
152 XML_SetCharacterDataHandler(p, text_proc);
153 XML_SetUserData(p, &fImpl->fData);
154
155 size_t len = fStream->read(NULL, 0);
156 fImpl->fBufferLen = len;
157 fImpl->fBuffer = sk_malloc_throw(len);
158 fStream->rewind();
159 size_t len2 = fStream->read(fImpl->fBuffer, len);
160 return len2 == len;
161 }
162
onExit()163 void SkXMLPullParser::onExit()
164 {
165 sk_free(fImpl->fBuffer);
166 XML_ParserFree(fImpl->fData.fParser);
167 delete fImpl;
168 fImpl = NULL;
169 }
170
onNextToken()171 SkXMLPullParser::EventType SkXMLPullParser::onNextToken()
172 {
173 if (Data::RETURN_END_TAG == fImpl->fData.fState)
174 {
175 fImpl->fData.fState = Data::NORMAL;
176 fCurr.fName = fImpl->fData.fEndTag; // restore name from (below) save
177 return SkXMLPullParser::END_TAG;
178 }
179
180 fImpl->fData.fAlloc.reuse();
181
182 XML_Parser p = fImpl->fData.fParser;
183 XML_Status status;
184
185 status = XML_ResumeParser(p);
186
187 CHECK_STATUS:
188 switch (status) {
189 case XML_STATUS_OK:
190 return SkXMLPullParser::END_DOCUMENT;
191
192 case XML_STATUS_ERROR:
193 if (XML_GetErrorCode(p) != XML_ERROR_NOT_SUSPENDED)
194 {
195 reportError(p);
196 return SkXMLPullParser::ERROR;
197 }
198 status = XML_Parse(p, (const char*)fImpl->fBuffer, fImpl->fBufferLen, true);
199 goto CHECK_STATUS;
200
201 case XML_STATUS_SUSPENDED:
202 if (Data::MISSED_START_TAG == fImpl->fData.fState)
203 {
204 // return a start_tag, and clear the flag so we return end_tag next
205 SkASSERT(SkXMLPullParser::END_TAG == fCurr.fEventType);
206 fImpl->fData.fState = Data::RETURN_END_TAG;
207 fImpl->fData.fEndTag = fCurr.fName; // save this pointer
208 return SkXMLPullParser::START_TAG;
209 }
210 break;
211 }
212 return fCurr.fEventType;
213 }
214
215