Segmentation fault when trying to parse xml file

[igoe]

I'm new to C programming. I want to create C program which can read XML file using libxml2.I tested this code:\[code\]#include <stdio.h>#include <string.h>#include <stdlib.h>#include <libxml/xmlmemory.h>#include <libxml/parser.h>// Declare functionsvoid parseSystemProperties(char *xmlFileName);void parseSystemModules(xmlDocPtr doc, xmlNodePtr cur);void parseSystemConfiguration(xmlDocPtr doc, xmlNodePtr cur);void parseProfiles(xmlDocPtr doc, xmlNodePtr cur);void parseMonitoringPort(xmlDocPtr doc, xmlNodePtr cur);void parseWebServicePort(xmlDocPtr doc, xmlNodePtr cur);void parseBindingInterfaces(xmlDocPtr doc, xmlNodePtr cur);void parseExtensions(xmlDocPtr doc, xmlNodePtr cur);int main(int argc, char **argv) { char *xmlFileName; if (argc <= 1) { printf("Usage: %s inputfile.xml\n", argv[0]); return (0); } // Get the file name from the argv[1] xmlFileName = argv[1]; // Custom function to parse XML file parseSystemProperties(xmlFileName); return (1);}// Parsing the XML file and Reading the Element Nodesvoid parseSystemProperties(char *xmlFileName) { xmlDocPtr doc; // pointer to parse xml Document xmlNodePtr cur; // node pointer. It interacts with individual node // Parse XML file doc = xmlParseFile(xmlFileName); // Check to see that the document was successfully parsed. if (doc == NULL) { fprintf(stderr, "Error!. Document is not parsed successfully. \n"); return; } // Retrieve the document's root element - system-properties cur = xmlDocGetRootElement(doc); // Check to make sure the document actually contains something if (cur == NULL) { fprintf(stderr, "Document is Empty\n"); xmlFreeDoc(doc); return; } /* We need to make sure the document is the right type. * "system-properties" is the root type of the documents used in user Config XML file */ if (xmlStrcmp(cur->name, (const xmlChar *) "system-properties")) { fprintf(stderr, "Cannot find system-properties"); xmlFreeDoc(doc); return; } /* Get the first child node of cur. * At this point, cur points at the document root, * which is the element "root" */ cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of "root" while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "system-modules"))) { parseSystemModules(doc, cur); } cur = cur->next; } cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of "root" while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "system-configuration"))) { parseSystemConfiguration(doc, cur); } cur = cur->next; } /* Save XML document to the Disk * Otherwise, you changes will not be reflected to the file. * Currently it's only in the memory */ // xmlSaveFormatFile (xmlFileName, doc, 1); /* free the document */ xmlFreeDoc(doc); /* * Free the global variables that may * have been allocated by the parser. */ xmlCleanupParser(); return;} // end of function// Get Modules part// -------------------------------------------void parseSystemModules(xmlDocPtr doc, xmlNodePtr cur) { xmlChar *key; xmlAttrPtr attr; // Get the sub Element Node of system-configuration node cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of system-configuration while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "extensions"))) { parseExtensions(doc, cur); } cur = cur->next; } return;} // end of function()void parseExtensions(xmlDocPtr doc, xmlNodePtr cur) { xmlChar *key; xmlAttrPtr attr; // Get the sub Element Node of Profiles node cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of Profiles while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "extension"))) { key = xmlGetProp(cur, (const xmlChar*) "module"); fprintf(stderr, "module: %s\n", key); xmlFree(key); } cur = cur->next; } return;} // end of function()// Get Configuration part// -------------------------------------------void parseSystemConfiguration(xmlDocPtr doc, xmlNodePtr cur) { xmlChar *key; xmlAttrPtr attr; // Get the sub Element Node of system-configuration node cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of system-configuration while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "profiles"))) { parseProfiles(doc, cur); } cur = cur->next; } return;} // end of function()void parseProfiles(xmlDocPtr doc, xmlNodePtr cur) { xmlChar *key; xmlAttrPtr attr; // Get the sub Element Node of Profiles node cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of Profiles while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "profile"))) { // Get monitoring-port parseMonitoringPort(doc, cur); // Get web-service-port parseWebServicePort(doc, cur); parseBindingInterfaces(doc, cur); } cur = cur->next; } return;} // end of function()// Monitoring Portvoid parseMonitoringPort(xmlDocPtr doc, xmlNodePtr cur) { xmlChar *key; xmlAttrPtr attr; // Get the sub Element Node of Profile node cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of Profile while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "monitoring-port"))) { key = xmlGetProp(cur, (const xmlChar*) "port"); fprintf(stderr, "monitoring-port: %s\n", key); xmlFree(key); } cur = cur->next; } return;} // end of function()// web service portvoid parseWebServicePort(xmlDocPtr doc, xmlNodePtr cur) { xmlChar *key; xmlAttrPtr attr; // Get the sub Element Node of Profile node cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of "root" while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "web-service-port"))) { //parseMonitoringPort (doc, cur); key = xmlGetProp(cur, (const xmlChar*) "port"); fprintf(stderr, "web-service-port: %s\n", key); xmlFree(key); } cur = cur->next; } return;} // end of function()// binding interfacevoid parseBindingInterfaces(xmlDocPtr doc, xmlNodePtr cur) { xmlChar *key; xmlAttrPtr attr; // Get the sub Element Node of Profile node cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of "root" while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "socket-binding"))) { //parseMonitoringPort (doc, cur); key = xmlGetProp(cur, (const xmlChar*) "interface"); fprintf(stderr, "interface: %s\n", key); xmlFree(key); } cur = cur->next; } return;} // end of function()\[/code\]This is the XML that I want to read:\[code\]<?xml version="1.0" encoding="UTF-8"?><system-properties version="1.0"> <system-modules> <extensions> <extension module="NetworkModule"/> <extension module="MonitoringModule"/> <extension module="OracleModule"/> <extension module="DataFilterModule"/> </extensions> </system-modules> <system-configuration> <profiles> <profile name="default"> <monitoring-port port="6051"/> <web-service-port port="7050"/> <socket-binding interface="management" ipaddress="192.168.1.101" port="6050"/> <socket-binding interface="monitoring" ipaddress="192.168.1.106" port="7050"/> <network-pool threads="40"/> </profile> </profiles> </system-configuration></system-properties>\[/code\]Unfortunately I get this error when I run the example:\[code\][rcbandit@Laptop Ctest]$ ./test xmlfile.xmlmodule: NetworkModulemodule: MonitoringModulemodule: OracleModulemodule: DataFilterModuleSegmentation fault (core dumped)[user@Laptop Ctest]$ \[/code\]When I remove this line the code works:\[code\]cur = cur->xmlChildrenNode; // This loop iterates through the elements that are children of "root" while (cur != NULL) { if ((!xmlStrcmp(cur->name, (const xmlChar *) "system-modules"))) { parseSystemModules(doc, cur); } cur = cur->next; }\[/code\]Can you help me to fix this problem?