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 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 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 { 39 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 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 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> 103 104 static bool isws(const char s[]) 105 { 106 for (; *s; s++) 107 if (!isspace(*s)) 108 return false; 109 return true; 110 } 111 112 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 }; 131 132 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 } 140 141 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 } 162 163 void SkXMLPullParser::onExit() 164 { 165 sk_free(fImpl->fBuffer); 166 XML_ParserFree(fImpl->fData.fParser); 167 delete fImpl; 168 fImpl = NULL; 169 } 170 171 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
