Added Group Parser

messenger/XML_Parser/groups_parser

@@ -0,0 +1,160 @@
+///////////////////////////////////////////////////////////////////////////////
+//
+// Group List Parser
+//
+///////////////////////////////////////////////////////////////////////////////
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "asm-xml.h"
+
+static const int  chunkSize = 16*1024*1024; // 16Mk
+static const char schemaFilename[] = "groups_schema.xml";
+static const char xmlFilename[]    = "groups.xml";
+
+char buffer[65536];
+
+///////////////////////////////////////////////////////////////////////////////
+// Print an attribute / text value
+///////////////////////////////////////////////////////////////////////////////
+const char* asString(AXAttribute* attr)
+{
+  const char* start = attr->begin;
+  const char* limit = attr->limit;
+  size_t size = limit - start;
+  memcpy(buffer, start, size);
+  buffer[size] = 0;
+  return buffer;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Print an error code from the parser
+///////////////////////////////////////////////////////////////////////////////
+void printAsmXmlError(AXParseContext* context)
+{
+  fprintf(stderr, "Error (%d,%d): %d\n", context->line, context->column, context->errorCode);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Read Schema Definition
+///////////////////////////////////////////////////////////////////////////////
+AXElementClass* readClass(const char* filename, AXClassContext* classContext)
+{
+  FILE*    f;
+  size_t  size;
+
+  f = fopen(filename, "rb");
+  if( f == NULL )
+  {
+    fprintf(stderr, "can't open schema '%s'\n", filename);
+    return NULL;
+  }
+  size = fread(buffer, 1, 65535, f);
+  buffer[size] = 0;
+  fclose(f);
+
+  // Parse the string and build the class
+  return ax_classFromString(buffer, classContext);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Read Document
+///////////////////////////////////////////////////////////////////////////////
+AXElement* readDocument(const char*     filename,
+                        AXParseContext* parseContext,
+                        AXElementClass* clazz)
+{
+  FILE*    f;
+  size_t  size;
+
+  f = fopen(filename, "rb");
+  if( f == NULL )
+  {
+    fprintf(stderr, "can't open file '%s'\n", filename);
+    return NULL;
+  }
+  size = fread(buffer, 1, 65535, f);
+  buffer[size] = 0;
+  fclose(f);
+
+  // Parse the string and build the class
+  return ax_parse(parseContext, buffer, clazz, 1);
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// main
+///////////////////////////////////////////////////////////////////////////////
+int main(int argc, char *argv[])
+{
+  int             res;
+  AXClassContext  classContext;
+  AXParseContext  parseContext;
+  AXElementClass* friendClass;
+  AXElement*      friends;
+  AXElement*      friend;
+
+  // Initialize the AsmXml library
+  //
+  // Pass the malloc() and free() functions
+  //
+  ax_initialize(malloc, free);
+
+  // Initialize the class context
+  //
+  // It can store one or more classes. Classes read with this
+  // context are kept in memory as long as it is not released.
+  //
+  res = ax_initializeClassParser(&classContext);
+  // An error while initialization means that allocation failed.
+  // It should never happen since it allocates only 4K.
+  if( res != 0 )
+    return 1;
+
+  // Read the schema and compile it
+  //
+  friendClass = readClass(schemaFilename, &classContext);
+  if( friendClass == NULL )
+    return 1;
+
+  // Initialize the parser
+  //
+  // Documents read with this parser will stay in memory as long as
+  // the parser is not released.
+  //
+  // The choice of the chunk size is very important since the
+  // performance can be affected by this value. The parser allocates
+  // memory by chunks to reduce calls to malloc that can be very slow.
+  // The ideal value is around 50% of the source XML to process.
+  //
+  res = ax_initializeParser(&parseContext, chunkSize);
+  // An error while initialization means that initial allocation failed.
+  if( res != 0 )
+    return 1;
+
+  // Read the file and parse it
+  //
+  friends = readDocument(xmlFilename, &parseContext, friendClass);
+  if( friends == NULL )
+  {
+    printAsmXmlError(&parseContext);
+    return 1;
+  }
+
+  // Enumerate child elements
+  friend = friends->firstChild;
+  while( friend )
+  {
+    printf("================================\n");
+    printf("Friend ID: %s\n", asString(&friend->attributes[0]));
+    printf("Name: %s\n", asString(&friend->attributes[1]));
+    printf("UserID: %s\n", asString(&friend->attributes[2]));
+    friend = friend->nextSibling;
+    printf("================================\n");
+  }
+
+  // Release the document and its class
+  ax_releaseParser(&parseContext);
+  ax_releaseClassParser(&classContext);
+  return 0;
+}