michael@0: 
michael@0: /*
michael@0:  * Copyright 2006 The Android Open Source Project
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "SkXMLParser.h"
michael@0: #include "SkChunkAlloc.h"
michael@0: #include "SkString.h"
michael@0: #include "SkStream.h"
michael@0: 
michael@0: #include "expat.h"
michael@0: 
michael@0: static inline char* dupstr(SkChunkAlloc& chunk, const char src[], size_t len)
michael@0: {
michael@0:     SkASSERT(src);
michael@0:     char*   dst = (char*)chunk.alloc(len + 1, SkChunkAlloc::kThrow_AllocFailType);
michael@0: 
michael@0:     memcpy(dst, src, len);
michael@0:     dst[len] = 0;
michael@0:     return dst;
michael@0: }
michael@0: 
michael@0: static inline int count_pairs(const char** p)
michael@0: {
michael@0:     const char** start = p;
michael@0:     while (*p)
michael@0:     {
michael@0:         SkASSERT(p[1] != NULL);
michael@0:         p += 2;
michael@0:     }
michael@0:     return (p - start) >> 1;
michael@0: }
michael@0: 
michael@0: struct Data {
michael@0:     Data() : fAlloc(2048), fState(NORMAL) {}
michael@0: 
michael@0:     XML_Parser              fParser;
michael@0:     SkXMLPullParser::Curr*  fCurr;
michael@0:     SkChunkAlloc            fAlloc;
michael@0: 
michael@0:     enum State {
michael@0:         NORMAL,
michael@0:         MISSED_START_TAG,
michael@0:         RETURN_END_TAG
michael@0:     };
michael@0:     State fState;
michael@0:     const char* fEndTag;    // if state is RETURN_END_TAG
michael@0: };
michael@0: 
michael@0: static void XMLCALL start_proc(void *data, const char *el, const char **attr)
michael@0: {
michael@0:     Data*                   p = (Data*)data;
michael@0:     SkXMLPullParser::Curr*  c = p->fCurr;
michael@0:     SkChunkAlloc&           alloc = p->fAlloc;
michael@0: 
michael@0:     c->fName = dupstr(alloc, el, strlen(el));
michael@0: 
michael@0:     int n = count_pairs(attr);
michael@0:     SkXMLPullParser::AttrInfo* info = (SkXMLPullParser::AttrInfo*)alloc.alloc(n * sizeof(SkXMLPullParser::AttrInfo),
michael@0:                                                                               SkChunkAlloc::kThrow_AllocFailType);
michael@0:     c->fAttrInfoCount = n;
michael@0:     c->fAttrInfos = info;
michael@0: 
michael@0:     for (int i = 0; i < n; i++)
michael@0:     {
michael@0:         info[i].fName = dupstr(alloc, attr[0], strlen(attr[0]));
michael@0:         info[i].fValue = dupstr(alloc, attr[1], strlen(attr[1]));
michael@0:         attr += 2;
michael@0:     }
michael@0: 
michael@0:     c->fEventType = SkXMLPullParser::START_TAG;
michael@0:     XML_StopParser(p->fParser, true);
michael@0: }
michael@0: 
michael@0: static void XMLCALL end_proc(void *data, const char *el)
michael@0: {
michael@0:     Data*                   p = (Data*)data;
michael@0:     SkXMLPullParser::Curr*  c = p->fCurr;
michael@0: 
michael@0:     if (c->fEventType == SkXMLPullParser::START_TAG)
michael@0:     {
michael@0:         /*  if we get here, we were called with a start_tag immediately
michael@0:             followed by this end_tag. The caller will only see the end_tag,
michael@0:             so we set a flag to notify them of the missed start_tag
michael@0:         */
michael@0:         p->fState = Data::MISSED_START_TAG;
michael@0: 
michael@0:         SkASSERT(c->fName != NULL);
michael@0:         SkASSERT(strcmp(c->fName, el) == 0);
michael@0:     }
michael@0:     else
michael@0:         c->fName = dupstr(p->fAlloc, el, strlen(el));
michael@0: 
michael@0:     c->fEventType = SkXMLPullParser::END_TAG;
michael@0:     XML_StopParser(p->fParser, true);
michael@0: }
michael@0: 
michael@0: #include <ctype.h>
michael@0: 
michael@0: static bool isws(const char s[])
michael@0: {
michael@0:     for (; *s; s++)
michael@0:         if (!isspace(*s))
michael@0:             return false;
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: static void XMLCALL text_proc(void* data, const char* text, int len)
michael@0: {
michael@0:     Data*                   p = (Data*)data;
michael@0:     SkXMLPullParser::Curr*  c = p->fCurr;
michael@0: 
michael@0:     c->fName = dupstr(p->fAlloc, text, len);
michael@0:     c->fIsWhitespace = isws(c->fName);
michael@0: 
michael@0:     c->fEventType = SkXMLPullParser::TEXT;
michael@0:     XML_StopParser(p->fParser, true);
michael@0: }
michael@0: 
michael@0: //////////////////////////////////////////////////////////////////////////
michael@0: 
michael@0: struct SkXMLPullParser::Impl {
michael@0:     Data    fData;
michael@0:     void*   fBuffer;
michael@0:     size_t  fBufferLen;
michael@0: };
michael@0: 
michael@0: static void reportError(XML_Parser parser)
michael@0: {
michael@0:     XML_Error code = XML_GetErrorCode(parser);
michael@0:     int lineNumber = XML_GetCurrentLineNumber(parser);
michael@0:     const char* msg = XML_ErrorString(code);
michael@0: 
michael@0:     printf("-------- XML error [%d] on line %d, %s\n", code, lineNumber, msg);
michael@0: }
michael@0: 
michael@0: bool SkXMLPullParser::onInit()
michael@0: {
michael@0:     fImpl = new Impl;
michael@0: 
michael@0:     XML_Parser p = XML_ParserCreate(NULL);
michael@0:     SkASSERT(p);
michael@0: 
michael@0:     fImpl->fData.fParser = p;
michael@0:     fImpl->fData.fCurr = &fCurr;
michael@0: 
michael@0:     XML_SetElementHandler(p, start_proc, end_proc);
michael@0:     XML_SetCharacterDataHandler(p, text_proc);
michael@0:     XML_SetUserData(p, &fImpl->fData);
michael@0: 
michael@0:     size_t len = fStream->getLength();
michael@0:     fImpl->fBufferLen = len;
michael@0:     fImpl->fBuffer = sk_malloc_throw(len);
michael@0:     fStream->rewind();
michael@0:     size_t  len2 = fStream->read(fImpl->fBuffer, len);
michael@0:     return len2 == len;
michael@0: }
michael@0: 
michael@0: void SkXMLPullParser::onExit()
michael@0: {
michael@0:     sk_free(fImpl->fBuffer);
michael@0:     XML_ParserFree(fImpl->fData.fParser);
michael@0:     delete fImpl;
michael@0:     fImpl = NULL;
michael@0: }
michael@0: 
michael@0: SkXMLPullParser::EventType SkXMLPullParser::onNextToken()
michael@0: {
michael@0:     if (Data::RETURN_END_TAG == fImpl->fData.fState)
michael@0:     {
michael@0:         fImpl->fData.fState = Data::NORMAL;
michael@0:         fCurr.fName = fImpl->fData.fEndTag; // restore name from (below) save
michael@0:         return SkXMLPullParser::END_TAG;
michael@0:     }
michael@0: 
michael@0:     fImpl->fData.fAlloc.reset();
michael@0: 
michael@0:     XML_Parser p = fImpl->fData.fParser;
michael@0:     XML_Status status;
michael@0: 
michael@0:     status = XML_ResumeParser(p);
michael@0: 
michael@0: CHECK_STATUS:
michael@0:     switch (status) {
michael@0:     case XML_STATUS_OK:
michael@0:         return SkXMLPullParser::END_DOCUMENT;
michael@0: 
michael@0:     case XML_STATUS_ERROR:
michael@0:         if (XML_GetErrorCode(p) != XML_ERROR_NOT_SUSPENDED)
michael@0:         {
michael@0:             reportError(p);
michael@0:             return SkXMLPullParser::ERROR;
michael@0:         }
michael@0:         status = XML_Parse(p, (const char*)fImpl->fBuffer, fImpl->fBufferLen, true);
michael@0:         goto CHECK_STATUS;
michael@0: 
michael@0:     case XML_STATUS_SUSPENDED:
michael@0:         if (Data::MISSED_START_TAG == fImpl->fData.fState)
michael@0:         {
michael@0:             // return a start_tag, and clear the flag so we return end_tag next
michael@0:             SkASSERT(SkXMLPullParser::END_TAG == fCurr.fEventType);
michael@0:             fImpl->fData.fState = Data::RETURN_END_TAG;
michael@0:             fImpl->fData.fEndTag = fCurr.fName;  // save this pointer
michael@0:             return SkXMLPullParser::START_TAG;
michael@0:         }
michael@0:         break;
michael@0:     }
michael@0:     return fCurr.fEventType;
michael@0: }