reed@android.com | 8a1c16f | 2008-12-17 15:59:43 +0000 | [diff] [blame^] | 1 | /* libs/graphics/ports/SkXMLParser_expat.cpp |
| 2 | ** |
| 3 | ** Copyright 2006, The Android Open Source Project |
| 4 | ** |
| 5 | ** Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | ** you may not use this file except in compliance with the License. |
| 7 | ** You may obtain a copy of the License at |
| 8 | ** |
| 9 | ** http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | ** |
| 11 | ** Unless required by applicable law or agreed to in writing, software |
| 12 | ** distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | ** See the License for the specific language governing permissions and |
| 15 | ** limitations under the License. |
| 16 | */ |
| 17 | |
| 18 | #include "SkXMLParser.h" |
| 19 | #include "SkChunkAlloc.h" |
| 20 | #include "SkString.h" |
| 21 | #include "SkStream.h" |
| 22 | |
| 23 | #include "expat.h" |
| 24 | |
| 25 | static inline char* dupstr(SkChunkAlloc& chunk, const char src[], size_t len) |
| 26 | { |
| 27 | SkASSERT(src); |
| 28 | char* dst = (char*)chunk.alloc(len + 1, SkChunkAlloc::kThrow_AllocFailType); |
| 29 | |
| 30 | memcpy(dst, src, len); |
| 31 | dst[len] = 0; |
| 32 | return dst; |
| 33 | } |
| 34 | |
| 35 | static inline int count_pairs(const char** p) |
| 36 | { |
| 37 | const char** start = p; |
| 38 | while (*p) |
| 39 | { |
| 40 | SkASSERT(p[1] != NULL); |
| 41 | p += 2; |
| 42 | } |
| 43 | return (p - start) >> 1; |
| 44 | } |
| 45 | |
| 46 | struct Data { |
| 47 | Data() : fAlloc(2048), fState(NORMAL) {} |
| 48 | |
| 49 | XML_Parser fParser; |
| 50 | SkXMLPullParser::Curr* fCurr; |
| 51 | SkChunkAlloc fAlloc; |
| 52 | |
| 53 | enum State { |
| 54 | NORMAL, |
| 55 | MISSED_START_TAG, |
| 56 | RETURN_END_TAG |
| 57 | }; |
| 58 | State fState; |
| 59 | const char* fEndTag; // if state is RETURN_END_TAG |
| 60 | }; |
| 61 | |
| 62 | static void XMLCALL start_proc(void *data, const char *el, const char **attr) |
| 63 | { |
| 64 | Data* p = (Data*)data; |
| 65 | SkXMLPullParser::Curr* c = p->fCurr; |
| 66 | SkChunkAlloc& alloc = p->fAlloc; |
| 67 | |
| 68 | c->fName = dupstr(alloc, el, strlen(el)); |
| 69 | |
| 70 | int n = count_pairs(attr); |
| 71 | SkXMLPullParser::AttrInfo* info = (SkXMLPullParser::AttrInfo*)alloc.alloc(n * sizeof(SkXMLPullParser::AttrInfo), |
| 72 | SkChunkAlloc::kThrow_AllocFailType); |
| 73 | c->fAttrInfoCount = n; |
| 74 | c->fAttrInfos = info; |
| 75 | |
| 76 | for (int i = 0; i < n; i++) |
| 77 | { |
| 78 | info[i].fName = dupstr(alloc, attr[0], strlen(attr[0])); |
| 79 | info[i].fValue = dupstr(alloc, attr[1], strlen(attr[1])); |
| 80 | attr += 2; |
| 81 | } |
| 82 | |
| 83 | c->fEventType = SkXMLPullParser::START_TAG; |
| 84 | XML_StopParser(p->fParser, true); |
| 85 | } |
| 86 | |
| 87 | static void XMLCALL end_proc(void *data, const char *el) |
| 88 | { |
| 89 | Data* p = (Data*)data; |
| 90 | SkXMLPullParser::Curr* c = p->fCurr; |
| 91 | |
| 92 | if (c->fEventType == SkXMLPullParser::START_TAG) |
| 93 | { |
| 94 | /* if we get here, we were called with a start_tag immediately |
| 95 | followed by this end_tag. The caller will only see the end_tag, |
| 96 | so we set a flag to notify them of the missed start_tag |
| 97 | */ |
| 98 | p->fState = Data::MISSED_START_TAG; |
| 99 | |
| 100 | SkASSERT(c->fName != NULL); |
| 101 | SkASSERT(strcmp(c->fName, el) == 0); |
| 102 | } |
| 103 | else |
| 104 | c->fName = dupstr(p->fAlloc, el, strlen(el)); |
| 105 | |
| 106 | c->fEventType = SkXMLPullParser::END_TAG; |
| 107 | XML_StopParser(p->fParser, true); |
| 108 | } |
| 109 | |
| 110 | #include <ctype.h> |
| 111 | |
| 112 | static bool isws(const char s[]) |
| 113 | { |
| 114 | for (; *s; s++) |
| 115 | if (!isspace(*s)) |
| 116 | return false; |
| 117 | return true; |
| 118 | } |
| 119 | |
| 120 | static void XMLCALL text_proc(void* data, const char* text, int len) |
| 121 | { |
| 122 | Data* p = (Data*)data; |
| 123 | SkXMLPullParser::Curr* c = p->fCurr; |
| 124 | |
| 125 | c->fName = dupstr(p->fAlloc, text, len); |
| 126 | c->fIsWhitespace = isws(c->fName); |
| 127 | |
| 128 | c->fEventType = SkXMLPullParser::TEXT; |
| 129 | XML_StopParser(p->fParser, true); |
| 130 | } |
| 131 | |
| 132 | ////////////////////////////////////////////////////////////////////////// |
| 133 | |
| 134 | struct SkXMLPullParser::Impl { |
| 135 | Data fData; |
| 136 | void* fBuffer; |
| 137 | size_t fBufferLen; |
| 138 | }; |
| 139 | |
| 140 | static void reportError(XML_Parser parser) |
| 141 | { |
| 142 | XML_Error code = XML_GetErrorCode(parser); |
| 143 | int lineNumber = XML_GetCurrentLineNumber(parser); |
| 144 | const char* msg = XML_ErrorString(code); |
| 145 | |
| 146 | printf("-------- XML error [%d] on line %d, %s\n", code, lineNumber, msg); |
| 147 | } |
| 148 | |
| 149 | bool SkXMLPullParser::onInit() |
| 150 | { |
| 151 | fImpl = new Impl; |
| 152 | |
| 153 | XML_Parser p = XML_ParserCreate(NULL); |
| 154 | SkASSERT(p); |
| 155 | |
| 156 | fImpl->fData.fParser = p; |
| 157 | fImpl->fData.fCurr = &fCurr; |
| 158 | |
| 159 | XML_SetElementHandler(p, start_proc, end_proc); |
| 160 | XML_SetCharacterDataHandler(p, text_proc); |
| 161 | XML_SetUserData(p, &fImpl->fData); |
| 162 | |
| 163 | size_t len = fStream->read(NULL, 0); |
| 164 | fImpl->fBufferLen = len; |
| 165 | fImpl->fBuffer = sk_malloc_throw(len); |
| 166 | fStream->rewind(); |
| 167 | size_t len2 = fStream->read(fImpl->fBuffer, len); |
| 168 | return len2 == len; |
| 169 | } |
| 170 | |
| 171 | void SkXMLPullParser::onExit() |
| 172 | { |
| 173 | sk_free(fImpl->fBuffer); |
| 174 | XML_ParserFree(fImpl->fData.fParser); |
| 175 | delete fImpl; |
| 176 | fImpl = NULL; |
| 177 | } |
| 178 | |
| 179 | SkXMLPullParser::EventType SkXMLPullParser::onNextToken() |
| 180 | { |
| 181 | if (Data::RETURN_END_TAG == fImpl->fData.fState) |
| 182 | { |
| 183 | fImpl->fData.fState = Data::NORMAL; |
| 184 | fCurr.fName = fImpl->fData.fEndTag; // restore name from (below) save |
| 185 | return SkXMLPullParser::END_TAG; |
| 186 | } |
| 187 | |
| 188 | fImpl->fData.fAlloc.reuse(); |
| 189 | |
| 190 | XML_Parser p = fImpl->fData.fParser; |
| 191 | XML_Status status; |
| 192 | |
| 193 | status = XML_ResumeParser(p); |
| 194 | |
| 195 | CHECK_STATUS: |
| 196 | switch (status) { |
| 197 | case XML_STATUS_OK: |
| 198 | return SkXMLPullParser::END_DOCUMENT; |
| 199 | |
| 200 | case XML_STATUS_ERROR: |
| 201 | if (XML_GetErrorCode(p) != XML_ERROR_NOT_SUSPENDED) |
| 202 | { |
| 203 | reportError(p); |
| 204 | return SkXMLPullParser::ERROR; |
| 205 | } |
| 206 | status = XML_Parse(p, (const char*)fImpl->fBuffer, fImpl->fBufferLen, true); |
| 207 | goto CHECK_STATUS; |
| 208 | |
| 209 | case XML_STATUS_SUSPENDED: |
| 210 | if (Data::MISSED_START_TAG == fImpl->fData.fState) |
| 211 | { |
| 212 | // return a start_tag, and clear the flag so we return end_tag next |
| 213 | SkASSERT(SkXMLPullParser::END_TAG == fCurr.fEventType); |
| 214 | fImpl->fData.fState = Data::RETURN_END_TAG; |
| 215 | fImpl->fData.fEndTag = fCurr.fName; // save this pointer |
| 216 | return SkXMLPullParser::START_TAG; |
| 217 | } |
| 218 | break; |
| 219 | } |
| 220 | return fCurr.fEventType; |
| 221 | } |
| 222 | |