src/download.c

   1 /*
   2  * viking -- GPS Data and Topo Analyzer, Explorer, and Manager
   3  *
   4  * Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.net>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 #include <stdio.h>
  27 #include <errno.h>
  28 #include <ctype.h>
  29 #include <string.h>
  30 #include <strings.h>
  31 #include <gtk/gtk.h>
  32 #include <sys/stat.h>
  33 #include <sys/types.h>
  34
  35 #include "download.h"
  36
  37 #ifdef HAVE_LIBCURL
  38 #include "curl_download.h"
  39 #else
  40 #include "http.h"
  41 #endif
  42
  43 #ifdef WINDOWS
  44
  45 #include <io.h>
  46 #define access(a,b) _access(a,b)
  47 #define close(a) closesocket(a)
  48
  49 char *dirname ( char * dir )
  50 {
  51   char *tmp = dir + strlen(dir) - 1;
  52   while ( tmp != dir && *tmp != '\\' )
  53     tmp--;
  54   *tmp = '\0';
  55   return dir;
  56 }
  57
  58 #else
  59
  60 #include <unistd.h>
  61 #include <sys/types.h>
  62
  63 /* dirname */
  64 #include <libgen.h>
  65
  66 #endif
  67
  68 static int check_map_file(FILE* f)
  69 {
  70   char **s;
  71   char *bp;
  72   int res = 0;  /* good */
  73   fpos_t pos;
  74   char buf[33];
  75   size_t nr;
  76   char * html_str[] = {
  77     "<html",
  78     "<!DOCTYPE html",
  79     "<head",
  80     "<title",
  81     NULL
  82   };
  83
  84
  85   bzero(buf, sizeof(buf));
  86   fgetpos(f, &pos);
  87   rewind(f);
  88   nr = fread(buf, 1, sizeof(buf) - 1, f);
  89   fsetpos(f, &pos);
  90   for (bp = buf; (bp < (buf + sizeof(buf) - 1)) && (nr > (bp - buf)); bp++) {
  91     if (!(isspace(*bp)))
  92       break;
  93   }
  94   if ((bp >= (buf + sizeof(buf) -1)) || ((bp - buf) >= nr))
  95     return(res);
  96   for (s = html_str; *s; s++) {
  97     if (strncmp(*s, bp, strlen(*s)) == 0)
  98       return(-1);
  99   }
 100   return(res);
 101 }
 102
 103 static int download( const char *hostname, const char *uri, const char *fn, DownloadOptions *options)
 104 {
 105   FILE *f;
 106   int ret;
 107   char *tmpfilename;
 108
 109   /* Check file */
 110   if ( access ( fn, F_OK ) == 0 )
 111   {
 112     /* File exists: return */
 113     return -3;
 114   } else {
 115     if ( errno == ENOENT)
 116     {
 117       char *tmp = g_strdup ( fn );
 118 #ifdef WINDOWS
 119       mkdir( dirname ( dirname ( tmp ) ) );
 120       g_free ( tmp ); tmp = g_strdup ( fn );
 121       mkdir( dirname ( tmp ) );
 122 #else
 123       mkdir( dirname ( dirname ( tmp ) ), 0777 );
 124       g_free ( tmp ); tmp = g_strdup ( fn );
 125       mkdir( dirname ( tmp ), 0777 );
 126 #endif
 127       g_free ( tmp );
 128     }
 129     /* create placeholder file */
 130     if ( ! (f = fopen ( fn, "w+b" )) ) /* immediately open file so other threads won't -- prevents race condition */
 131       return -4;
 132     fclose ( f );
 133   }
 134
 135   tmpfilename = g_strdup_printf("%s.tmp", fn);
 136   f = fopen ( tmpfilename, "w+b" );
 137   if ( ! f ) {
 138     g_free ( tmpfilename );
 139     remove ( fn ); /* couldn't create temporary. delete 0-byte file. */
 140     return -4;
 141   }
 142
 143   /* Call the backend function */
 144 #ifdef HAVE_LIBCURL
 145   ret = curl_download_get_url ( hostname, uri, f, options );
 146 #else
 147   ret = http_download_get_url ( hostname, uri, f, 0, options );
 148 #endif
 149
 150   if (ret == -1 || ret == 1 || ret == -2 || check_map_file(f))
 151   {
 152     g_warning("Download error: %s\n", fn);
 153     fclose ( f );
 154     remove ( tmpfilename );
 155     g_free ( tmpfilename );
 156     remove ( fn ); /* couldn't create temporary. delete 0-byte file. */
 157     return -1;
 158   }
 159
 160   fclose ( f );
 161   rename ( tmpfilename, fn ); /* move completely-downloaded file to permanent location */
 162   g_free ( tmpfilename );
 163   return ret;
 164 }
 165
 166 /* success = 0, -1 = couldn't connect, -2 HTTP error, -3 file exists, -4 couldn't write to file... */
 167 /* uri: like "/uri.html?whatever" */
 168 /* only reason for the "wrapper" is so we can do redirects. */
 169 int a_http_download_get_url ( const char *hostname, const char *uri, const char *fn, DownloadOptions *opt )
 170 {
 171   return download ( hostname, uri, fn, opt );
 172 }