path: root/server/src/saxparser.cc

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/***************************************************************************
 *            saxparser.cc
 *
 *  Mon Mar 24 14:40:15 CET 2008
 *  Copyright 2008 Bent Bisballe Nyeng
 *  deva@aasimon.org
 ****************************************************************************/

/*
 *  This file is part of Pracro.
 *
 *  Pracro is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  Pracro is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Pracro; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 */
#include "saxparser.h"
#include "debug.h"

#include <string.h>

static void character_hndl(void *p, const XML_Char *s, int len)
{
  SAXParser *parser = (SAXParser*)XML_GetUserData(p);
  std::string chars;
  chars.append(s, len);
  parser->characterData(chars);
}

static void start_hndl(void *p, const char *el, const char **attr)
{
  SAXParser *parser = (SAXParser*)XML_GetUserData(p);

  // Convert to comfy C++ values...
  std::string name = el;
  std::map< std::string, std::string > attributes;

  while(*attr) {
    std::string at_name = *attr;
    attr++;
    std::string at_value = *attr;
    attr++;

    attributes.insert(make_pair(at_name, at_value));
  }

  if(parser->outertag == "") parser->outertag = name;

  parser->startTag(name, attributes);
}

static void end_hndl(void *p, const char *el)
{
  SAXParser *parser = (SAXParser*)XML_GetUserData(p);
  std::string name = el;

  if(name == parser->outertag) parser->done = true;

  parser->endTag(name);
}


SAXParser::SAXParser()
{
  p = XML_ParserCreate(NULL);
  if(!p) {
    PRACRO_ERR_LOG(sax, "Couldn't allocate memory for parser\n");
    // throw Exception(...);
    return;
  }

  XML_SetUserData(p, this);
  XML_UseParserAsHandlerArg(p);
  XML_SetElementHandler(p, start_hndl, end_hndl);
  XML_SetCharacterDataHandler(p, character_hndl);

  bufferbytes = 0;
  totalbytes = 0;
  done = false;

}

SAXParser::~SAXParser()
{
  if(p) XML_ParserFree(p);
}

int SAXParser::parse()
{
  char buf[32];
  int len;
  
  do {
    len = readData(buf, sizeof(buf) - 1);
    if (! XML_Parse(p, buf, len, len == 0)) {
      parseError(buf, len, XML_ErrorString(XML_GetErrorCode(p)), (int)XML_GetCurrentLineNumber(p));
      return 1;
    }

    memset(buf, 0, sizeof(buf));
  } while(len);

  return 0;
}

static bool iswhitespace(char *buf, size_t size)
{
  for(size_t i = 0; i < size; i++)
    if(buf[i] != ' ' && buf[i] != '\n' && buf[i] != '\t' && buf[i] != '\r')
      return false;
  return true;
}

bool SAXParser::parse(char *data, size_t size)
{
  PRACRO_DEBUG(sax, "parse %d bytes\n", size);

  bufferbytes = size;
  totalbytes += bufferbytes;

  if(! XML_Parse(p, data, size, false) ) {
    if(XML_GetErrorCode(p) == XML_ERROR_JUNK_AFTER_DOC_ELEMENT) return true;
    if(XML_GetErrorCode(p) == XML_ERROR_FINISHED && iswhitespace(data, size)) return true;
    if(done && XML_GetErrorCode(p) == XML_ERROR_UNCLOSED_TOKEN) return true;
    parseError(data, size, XML_ErrorString(XML_GetErrorCode(p)), (int)XML_GetCurrentLineNumber(p));
    return false;
  }

  if(done) {
    if(! XML_Parse(p, data, 0, true) ) {
      if(XML_GetErrorCode(p) == XML_ERROR_JUNK_AFTER_DOC_ELEMENT) return true;
      if(XML_GetErrorCode(p) == XML_ERROR_FINISHED && iswhitespace(data, size)) return true;
      if(XML_GetErrorCode(p) == XML_ERROR_UNCLOSED_TOKEN) return true;
      parseError(data, 0, XML_ErrorString(XML_GetErrorCode(p)), (int)XML_GetCurrentLineNumber(p));
      return false;
    }
  }

  if(done) PRACRO_DEBUG(sax, "Got END_OF_DOCUMENT [%s] at %ld\n", outertag.c_str(), XML_GetCurrentByteIndex(p));

  return done;
}

void SAXParser::parseError(char *buf, size_t len, std::string error, int lineno)
{
  fprintf(stderr, "SAXParser error at line %d: %s\n", lineno, error.c_str());
  fprintf(stderr, "\tBuffer %u bytes: [", len);
  if(fwrite(buf, len, 1, stderr) != len) {}
  fprintf(stderr, "]\n");
  fflush(stderr);
}

unsigned int SAXParser::usedBytes()
{
  return bufferbytes + (XML_GetCurrentByteIndex(p) - totalbytes);
}


#ifdef TEST_SAXPARSER

#define XMLFILE "/tmp/saxparsertest.xml"

#include "exception.h"

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>
#include <stdio.h>
#include <memory.h>

static char xml[] =
"<?xml version='1.0' encoding='UTF-8'?>\n"
"<pracro version=\"1.0\" user=\"testuser\" cpr=\"1505050505\">\n"
" <commit version=\"\" macro=\"referral\" course=\"amd_forunders\">\n"
"  <field value=\"Some docs\" name=\"referral.doctor\"/>\n"
"  <field value=\"DIMS\" name=\"referral.diagnosecode\"/>\n"
"  <field value=\"Avs\" name=\"referral.diagnose\"/>\n"
" </commit>\n"
"</pracro>\n         \t\n\r"
  ;

static char xml_notrailingwhitespace[] =
"<?xml version='1.0' encoding='UTF-8'?>\n"
"<pracro version=\"1.0\" user=\"testuser\" cpr=\"1505050505\">\n"
" <commit version=\"\" macro=\"referral\" course=\"amd_forunders\">\n"
"  <field value=\"Some docs\" name=\"referral.doctor\"/>\n"
"  <field value=\"DIMS\" name=\"referral.diagnosecode\"/>\n"
"  <field value=\"Avs\" name=\"referral.diagnose\"/>\n"
" </commit>\n"
"</pracro>"
  ;

static char xml_fail[] =
"<?xml version='1.0' encoding='UTF-8'?>\n"
"<pracro version=\"1.0\" user\"testuser\" cpr=\"1505050505\">\n"
" <request macro=\"test\" course=\"test\"/>\n"
"</pracro>\n"
  ;

static char xml_fail2[] =
"<?xml version='1.0' encoding='UTF-8'?>\n"
"<pracro version=\"1.0\" user\"testuser\" cpr=\"1505050505\">\n"
" <request macro=\"test\" course=\"test\"/>\n"
"</pracro>\n"
"this is junk\n"
  ;

class MyFileParser :public SAXParser {
public:
  MyFileParser(const char *file) {
    fd = open(file, O_RDONLY);
  }

  int readData(char *data, size_t size) {
    return read(fd, data, size);
  }

  void startTag(std::string name, std::map< std::string, std::string> attributes)
  {
    //printf("<%s>\n", name.c_str());
  }

  void parseError(char *buf, size_t len, std::string error, int lineno)
  {
    throw Exception(error);
  }

private:
  int fd;
};

class MyBufferParser :public SAXParser {
public:
  void startTag(std::string name, std::map< std::string, std::string> attributes)
  {
    //printf("<%s>\n", name.c_str());
  }

  void parseError(char *buf, size_t len, std::string error, int lineno)
  {
    throw Exception(error);
  }
};

int main(int argc, char *argv[])
{
  FILE *fp = fopen(XMLFILE, "w");
  if(!fp) {
    printf("Could not write to %s\n", XMLFILE);
    return 1;
  }
  fprintf(fp, xml);
  fclose(fp);

  // Test callback parser
  {
    MyFileParser parser(XMLFILE);
    parser.parse();
  }

  // Test buffer parser
  for(size_t sz = 1; sz < 1000; sz++) {
    bool test = false;
    MyBufferParser parser;
    std::string buf = xml;
    size_t pos = 0;
    while(pos < buf.length()) {
      std::string substr = buf.substr(pos, sz);

      try {
        test |= parser.parse((char*)substr.c_str(), substr.length());
      } catch(Exception &e) {
        printf("Buffer parser failed on size %d: %s [%s]\n", sz, e.what(), substr.c_str());
      }
      pos += sz;
    }

    if(!test) {
      printf("Buffer parser failed on size %d\n", sz);
      return 1;
    }
  }

  fp = fopen(XMLFILE, "w");
  if(!fp) {
    printf("Could not write to %s\n", XMLFILE);
    return 1;
  }
  fprintf(fp, xml_notrailingwhitespace);
  fprintf(fp, xml_notrailingwhitespace);
  fclose(fp);
  // Test buffer parser with multiple documents in the same buffer
  {
    fp = fopen(XMLFILE, "r");
    if(!fp) {
      printf("Could not write to %s\n", XMLFILE);
      return 1;
    }
    for(size_t sz = 1; sz < 1000; sz++) {
      MyBufferParser *parser = NULL;
      rewind(fp);
      size_t numdocs = 0;
      char *buf = new char[sz + 1];
      memset(buf, 0, sz + 1);
      size_t size;
      while( (size = fread(buf, 1, sz, fp)) > 0) {
        while(size) {
          if(parser == NULL) {
            parser = new MyBufferParser();
          }
          if(parser->parse(buf, size)) {

            // Got one
            numdocs++;

            size = size - parser->usedBytes();
            strcpy(buf, buf + parser->usedBytes());
            delete parser; parser = NULL;
          } else {
            size = 0;
            memset(buf, 0, sz + 1);
          }
        }
      }
      if(numdocs != 2) {
        printf("Failed to parse two documents.\n");
        return 1;
      }
      if(parser) delete parser; parser = NULL;
      delete[] buf;
    }
    fclose(fp);
  }

  fp = fopen(XMLFILE, "w");
  if(!fp) {
    printf("Could not write to %s\n", XMLFILE);
    return 1;
  }
  fprintf(fp, xml_fail);
  fclose(fp);

  // Test failure
  {
    MyFileParser parser(XMLFILE);
    try {
      parser.parse();
    } catch(Exception &e) {
      goto goon;
    }
    printf("This test should fail...\n");
    return 1;
  }
 goon:

  fp = fopen(XMLFILE, "w");
  if(!fp) {
    printf("Could not write to %s\n", XMLFILE);
    return 1;
  }
  fprintf(fp, xml_fail2);
  fclose(fp);

  // Test failure
  {
    MyFileParser parser(XMLFILE);
    try {
      parser.parse();
    } catch(Exception &e) {
      goto goonagain;
    }
    printf("This test should fail...\n");
    return 1;
  }
 goonagain:

  unlink(XMLFILE);
}

#endif/*TEST_SAXPARSER*/