fetch_file.c

/*****************************************************************************
 *                        fetch_file.c
 * This file contains functions which are used to download remote files. If 
 * the input is a url, then the functions defined below are used to parse the
 * url and download the remote file.
 *
 ****************************************************************************/

#include "xsb_config.h"
#include "socketcall.h"
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>


#define SA      struct sockaddr

#define MAXSTRLEN 256

int parse_url( const char * url, char * server, char *fname);
int get_file_www(char *server, char * fname, char **buf);


int parse_url( const char * url, char * server, char *fname)
{
  int i,j;
  int len = strlen(url);
  char temp[MAXSTRLEN];
  
  int flag = 0, flag_file = 0;
  
  for(i = 0; i<MAXSTRLEN; i++)
    {
      *(server+i) = 0;
      *(fname+i) = 0;
      *(temp+i) = 0;
    }
  
  
  for( i=0;i<len;i++)
    {
      *(temp+i)=url[i];
      
      if( url[i] == ':')
        {
          
          flag = 1;
          i++;
          /*If the protocol is not file:// or http:// its an error*/
          if(strcmp( temp , "http:") && strcmp( temp, "file:"))
            return FALSE;
          
          if(!strcmp( temp, "http:")){
            flag_file = 1;
          }
          else if(!strcmp( temp, "file:")){
            flag_file = 2;
          }
          
          if( url[i] == '/' && url[i+1] == '/')
            {
              *(temp+i) = url[i];
              i = i+ 1;         
              *(temp+i) = url[i];
              i = i+1;
              break;
            }
          else
            return FALSE;
        }
    }
  
  if(!flag)
    return FALSE;
  
  if( flag_file == 2){
    strcpy( server, "file");
    strcpy( fname, url+i);
    return TRUE;
  }
  
  /*Extract the server*/
  for(j=0;i<len;i++,j++)
    {
      if(url[i] == '/')
        break;
      
      *(server+j) = url[i];
    }
  /*Extract the filename*/
  for(j=0;i<len;i++,j++)
    {
      *(fname+j) = url[i];
        }
  return TRUE;
}

int get_file_www(char *server, char *fname, char **source)
{
        int sockfd;
        struct sockaddr_in      servaddr;
        struct in_addr          **pptr;
        struct hostent          *hp;
        int port = 80, len, i = 0, maxlen = 0;
        char *tempstr = NULL;
        
        /*Special socket handling for windows*/
#ifdef WIN_NT
        int rc;
        WSADATA wsadata;
        
        rc = WSAStartup(2, &wsadata);
        *source = (char*)malloc(MAXSTRLEN);
        if(rc) {
          sprintf( *source, "WSAStartup FAILED: err=%d\n", (int) GetLastError());
          return FALSE;
        }
#endif
        
        if(*source == NULL)
        {
                *source = (char*)malloc(MAXSTRLEN);
        }

        len = strlen( server);
        
        for( i = 0; i < len && server[i] != ':'; i++);
        
        if (server[i] == ':')
          {
            server[i] = 0;
                port = atoi(server + i + 1);
          }

        /*Resolve the hostname*/
        if ( (hp = gethostbyname(server)) == NULL)
          {
            sprintf(*source, "hostname error for %s", server);
            return FALSE;
          }
        
        pptr = (struct in_addr **) hp->h_addr_list;
        
        /* Open the socket connection */        
        for ( ; *pptr != NULL; pptr++) {
          
          sockfd = socket(AF_INET, SOCK_STREAM, 0);
          
          
          memset(&servaddr, 0, sizeof(servaddr));
          servaddr.sin_family = AF_INET;
          servaddr.sin_port = htons((unsigned short)port); 
          memcpy(&servaddr.sin_addr, *pptr, sizeof(struct in_addr));
          if (connect(sockfd, (SA *) &servaddr, sizeof(servaddr)) == 0)
            break;              
#ifdef WIN_NT
          closesocket(sockfd);
#else
          close(sockfd);
#endif
          return FALSE;
        }
        if (*pptr == NULL)
          {
            return FALSE;
          }
        
        len = 0;
        

        /*Issue the http get filename command*/
        //      printf("Server [%s] Fname [%s]\n", server, fname);      
        
        sprintf( *source, "GET %s\n\n", fname);
        len = strlen( *source);
        (*source)[ len] = '\0';
        send( sockfd, *source, strlen(*source), 0);
                    
        i=0;
        maxlen = 0;

        /* Download the file */
        while( (len != 0)  && ( len != -1)){
          *source = (char*) realloc( *source, ((i+1) * MAXSTRLEN) + 1);
           tempstr = (*source) + maxlen;
          len = recv( sockfd, tempstr , MAXSTRLEN, 0);
          
          if( (len != 0) && (len != -1) ){
            maxlen+=len;
            (*source)[maxlen]='\0';
          }
          i++;
        }
        
        //        printf("Downloaded [%s]\n", *source);
        /*Handle http errors*/

        if( (strstr( *source, "Error 400")!= NULL)
            || (strstr( *source, "400 Bad Request")!=NULL)){
          strcpy( *source, "400 Bad Request");
          return FALSE;
        }
        
        if( (strstr( *source, "Error 401")!= NULL)
            || (strstr( *source, "401 Unauthorized")!=NULL)){
          strcpy( *source, "401 Unauthorized");
          return FALSE;
        }
        
        if( (strstr( *source, "Error 402")!= NULL)
        || (strstr( *source, "402 Payment Required")!=NULL)){
          strcpy( *source, "402 Payment Required");
          return FALSE;
        }
        
        if( (strstr( *source, "Error 403")!= NULL)
            || strstr( *source, "403 Forbidden")!=NULL){
          strcpy( *source, "403 Forbidden");
          return FALSE;
        }
        
        if( (strstr( *source, "Error 404")!= NULL) 
            || (strstr( *source, "404 Not Found")!=NULL)){
            strcpy( *source, "Error 404 File not found");
            return FALSE;
          }
        
        if( (strstr( *source, "Error 405")!= NULL)
            || (strstr( *source, "405 Method Not Allowed")!=NULL)){
          strcpy( *source, "405 Method Not Allowed");
          return FALSE;
        }
        
        if( (strstr( *source, "Error 406")!= NULL)
            || (strstr( *source, "406 Not Acceptable")!=NULL)){
          strcpy( *source, "406 Not Acceptable");
          return FALSE;
        }

        if( (strstr( *source, "Error 407")!= NULL)
            || (strstr( *source, "407  Proxy Authentication Required")!=NULL)  ){
          strcpy( *source, "407 Proxy Authentication Required");
          return FALSE;
        }
        
        
        if( (strstr( *source, "Error 408")!= NULL)
        || (strstr( *source, "408 Request Timeout")!=NULL)){
          strcpy( *source, "408 Request Timeout");
          return FALSE;
        }

        if( (strstr( *source, "Error 409")!= NULL)
        || (strstr( *source, "409 Conflict")!=NULL)){
          strcpy( *source, "409 Conflict");
          return FALSE;
        }


        if( (strstr( *source, "Error 410")!= NULL)
         || (strstr( *source, "410 Gone")!=NULL)){
          strcpy( *source, "410 Gone");
          return FALSE;
        }

        if( (strstr( *source, "Error 411")!= NULL)
          || (strstr( *source, "411 Length Required")!=NULL)){
          strcpy( *source, "411 Length Required"); ;
          return FALSE;
        }
        if( (strstr( *source, "Error 412")!= NULL)
        || (strstr( *source, "412 Precondition failed")!=NULL)){
          strcpy( *source, "412 Precondition Failed");
          return FALSE;
        }

        if( (strstr( *source, "Error 413")!= NULL)
        || (strstr( *source, "413 Request Entity Too Large")!=NULL)){
          strcpy( *source, "413 Request Entity Too Large");
          return FALSE;
        }

        if( (strstr( *source, "Error 414")!= NULL)
        || (strstr( *source, "414 Request-URI Too Long")!=NULL)){
          strcpy( *source, "414 Request-URI Too Long") ;
          return FALSE;
        }

        if( (strstr( *source, "Error 415")!= NULL)
        || (strstr( *source, "Error 415")!=NULL)){
          strcpy( *source, "415 Unsupported Media Type");
          return FALSE;
        }
        
        if( (strstr( *source, "Error 416")!= NULL)
        || (strstr( *source, "416 Requested Range Not Satisfiable")!=NULL)){
          strcpy( *source, "416 Requested Range Not Satisfiable");
          return FALSE;
        }

        if( (strstr( *source, "Error 417")!= NULL)
        || (strstr( *source, "417 Expectation Failed")!=NULL)){
          strcpy( *source,  "417 Expectation Failed");
          return FALSE;
        }

        if( (strstr( *source, "Error 500")!= NULL)
        || (strstr( *source, "500 Internal Server Error")!=NULL)){
          strcpy( *source, "500 Internal Server Error");
          return FALSE;
        }
         
        if( (strstr( *source, "Error 501")!= NULL)
        || (strstr( *source, "501 Not Implemented")!=NULL)){
          strcpy( *source, "501 Not Implemented");
          return FALSE;
        }
        if( (strstr( *source, "Error 502")!= NULL)
        || (strstr( *source, "502 Bad Gateway")!=NULL)){
          strcpy( *source, "502 Bad Gateway");
          return FALSE;
        }

        if( (strstr( *source, "Error 503")!= NULL)
        || (strstr( *source, "503 Service Unavailable")!=NULL)){
          strstr( *source, "503 Service Unavailable") ;
          return FALSE;
        }

        if( (strstr( *source, "Error 504")!= NULL)
            || (strstr( *source, "504 Gateway Timeout")!=NULL))
          {
          strcpy( *source, "504 Gateway Timeout");
          return FALSE;
        }

        if( (strstr( *source, "Error 505")!= NULL)
        || (strstr( *source, "505 HTTP Version Not Supported")!=NULL)){
          strcpy( *source, "505 HTTP Version Not Supported");
          return FALSE;
        }

#ifdef WIN_NT
        closesocket(sockfd);
#else
        close(sockfd);
#endif

        return TRUE;
}

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