[C language] 利用libexpat 解析XML，简单好用

libexpat.so解析xml使用非常方便

著名的Wayland也使用了此库解析XML，俗称：协议protocol.

test_expat.c:

#include <stdio.h>
#include <string>
#include <iostream>
#include <string.h>

#include "expat.h"

using namespace std;

#define XML_FMT_INT_MOD "l"

#define Max_STORAGE 0x200
static bool sectPrStart = false;
char *pfind = NULL;
static char nameget[100] ={0};
static void StartElementHandler(void *userData,const XML_Char *name,
                                const XML_Char **atts)
{
 //if(!strcmp(pfind,name))
 { 
  sectPrStart = true;
  for (int i = 0; atts[i] != 0; i += 2)
  {
   cout << "name: " << atts[i] << endl;
   cout << "value: " << atts[i+1] << endl;
  }
 }
}

static void EndElementHandler(void *userData,const XML_Char *name)
{
 
 //if(!strcmp(pfind,name))
 {
  sectPrStart = false;
  sprintf(nameget,"copy %s",name);
  cout << "End element name: " << nameget<< endl;
  cout << "End element name: " << name << endl;
 }
}

static void CharacterDataHandler(void *userData,const XML_Char *s,
                                 int len)
{
 if(sectPrStart && s)
 {
  string str(s,len);
  cout << "inner Text: " << str << endl;
 }
}

int main(int argc, char *argv[])
{
 cout << "Start............................." << endl;
 int i = 0;
 pfind = argv[2];

 XML_Parser parser = XML_ParserCreate(NULL);
 XML_SetUserData(parser, &i);
 XML_SetElementHandler(parser, &StartElementHandler,&EndElementHandler);
 {
  XML_SetCharacterDataHandler(parser,&CharacterDataHandler);
 }

 int size_buf = Max_STORAGE;
 void* buf = malloc(size_buf);
  
 const char* file_path = argv[1];
 FILE* file = fopen(file_path,"r");
 
 int ret = 0;
 while(!feof(file))
 {
  ret = fread(buf,1,size_buf,file);
  cout << "ret: " << ret << endl;
  if (XML_Parse(parser, (char*) buf, ret, 0) == XML_STATUS_ERROR)
  {
   fprintf(stderr, "%s at line %" XML_FMT_INT_MOD "u ->%s\n",
     XML_ErrorString(XML_GetErrorCode(parser)),
     XML_GetCurrentLineNumber(parser), file_path);
   break;
  }
 }
 //last call
 XML_Parse(parser, (char*) 0, 0, 1);

 free(buf);
 XML_ParserFree(parser);
 fclose(file);
 cout << "End............................." << endl;
 return 0;
}