Wurfl library

wurfl.c

#include <stdio.h>
#include <string.h>
#include <libxml/parser.h>
#include <libxml/tree.h>
#include <libxml/xpath.h>
#include <libxml/xpathInternals.h>
#include "wurfl.h"

xmlDoc *doc = NULL;


int wurfl_init(char *filename) {
  doc = xmlReadFile(filename, NULL, 0);
  return (doc != NULL);
}


char wurfl_device(char *useragent) {
  xmlXPathContextPtr xpathCtx;
  xmlXPathObjectPtr xpathObj;

  // Lazy loading. Varnish does not support an init() function
  if (doc == NULL) wurfl_init("/etc/wurfl.xml");

  // Create new context
  xpathCtx = xmlXPathNewContext(doc);

  if (xpathCtx == NULL) return -1;

  // Create xpath expression
  char *expr = malloc(strlen(useragent) + 50);
  sprintf(expr, "//devices/device[@user_agent='%s']", (unsigned char *)useragent);
  xpathObj = xmlXPathEvalExpression(expr, xpathCtx);
  free(expr);

  // Nothing found?
  if (xpathObj == NULL) {
    xmlXPathFreeContext(xpathCtx);
    return ' ';
  }

  // Fetch the number of nodes found
  xmlNodeSetPtr nodes = xpathObj->nodesetval;
  char *device = xmlGetProp(nodes->nodeTab[0], "fall_back");

  // Something has been found...
  xmlXPathFreeObject(xpathObj);
  xmlXPathFreeContext(xpathCtx);
  xmlFree(device);

  return *device;
}

wurfl.h

#ifndef __WURFL_H__
#define __WURFL_H__

int wurfl_init(char *filename);
char wurfl_device(char *useragent);

#endif // __WURFL_H__

wurfl.sh

#!/bin/sh
echo -e '\n\n=============== Installing gem dependencies'
apt-get intall libxml2-dev

echo -e '\n\n=============== Compiling wurfl library'
wget https://raw.github.com/gist/3287591/afa1b6699e8524d0d3aa5c0d64ff4a76042d7891/wurfl.c
wget https://raw.github.com/gist/3287591/7a8464332553be89a66722de15f19ab6e8bc0056/wurfl.h
gcc -c -o wurfl.o wurfl.c -I/usr/include/libxml2 -fPIC
gcc -shared -Wl,-soname,libwurfl.so.1 -o libwurfl.so.1.0.1 wurfl.o -lxml2

echo -e '\n\n=============== Getting wurfl xml database'
wget http://sourceforge.net/projects/wurfl/files/WURFL/2.3.2/wurfl-2.3.2.xml.gz/download
gzip -d wurfl-2.3.2.xml.gz

echo -e '\n\n=============== Copy files'
mv wurfl-2.3.2.xml /etc/wurfl.xml
cp libwurfl.so.1.0.1 /usr/lib/libwurfl.so
ln -s /usr/lib/libwurfl.so /usr/lib64/libwurfl.so