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 <ctype.h>
  28 #include <string.h>
  29 #include <glib.h>
  30 #include <glib/gstdio.h>
  31 #include <glib/gi18n.h>
  32
  33 #include "download.h"
  34
  35 #include "curl_download.h"
  36
  37 static gboolean check_file_first_line(FILE* f, gchar *patterns[])
  38 {
  39   gchar **s;
  40   gchar *bp;
  41   fpos_t pos;
  42   gchar buf[33];
  43   size_t nr;
  44
  45   memset(buf, 0, sizeof(buf));
  46   fgetpos(f, &pos);
  47   rewind(f);
  48   nr = fread(buf, 1, sizeof(buf) - 1, f);
  49   fsetpos(f, &pos);
  50   for (bp = buf; (bp < (buf + sizeof(buf) - 1)) && (nr > (bp - buf)); bp++) {
  51     if (!(isspace(*bp)))
  52       break;
  53   }
  54   if ((bp >= (buf + sizeof(buf) -1)) || ((bp - buf) >= nr))
  55     return FALSE;
  56   for (s = patterns; *s; s++) {
  57     if (strncasecmp(*s, bp, strlen(*s)) == 0)
  58       return TRUE;
  59   }
  60   return FALSE;
  61 }
  62
  63 gboolean a_check_html_file(FILE* f)
  64 {
  65   gchar * html_str[] = {
  66     "<html",
  67     "<!DOCTYPE html",
  68     "<head",
  69     "<title",
  70     NULL
  71   };
  72
  73   return check_file_first_line(f, html_str);
  74 }
  75
  76 gboolean a_check_map_file(FILE* f)
  77 {
  78   /* FIXME no more true since a_check_kml_file */
  79   return !a_check_html_file(f);
  80 }
  81
  82 gboolean a_check_kml_file(FILE* f)
  83 {
  84   gchar * kml_str[] = {
  85     "<?xml",
  86     NULL
  87   };
  88
  89   return check_file_first_line(f, kml_str);
  90 }
  91
  92 static int download( const char *hostname, const char *uri, const char *fn, DownloadOptions *options, gboolean ftp)
  93 {
  94   FILE *f;
  95   int ret;
  96   gchar *tmpfilename;
  97   gboolean failure = FALSE;
  98
  99   /* Check file */
 100   if ( g_file_test ( fn, G_FILE_TEST_EXISTS ) == TRUE )
 101   {
 102     /* File exists: return */
 103     return -3;
 104   } else {
 105     gchar *dir = g_path_get_dirname ( fn );
 106     g_mkdir_with_parents ( dir , 0777 );
 107     g_free ( dir );
 108
 109     /* create placeholder file */
 110     if ( ! (f = g_fopen ( fn, "w+b" )) ) /* immediately open file so other threads won't -- prevents race condition */
 111       return -4;
 112     fclose ( f );
 113     f = NULL;
 114   }
 115
 116   tmpfilename = g_strdup_printf("%s.tmp", fn);
 117   f = g_fopen ( tmpfilename, "w+b" );
 118   if ( ! f ) {
 119     g_free ( tmpfilename );
 120     g_remove ( fn ); /* couldn't create temporary. delete 0-byte file. */
 121     return -4;
 122   }
 123
 124   /* Call the backend function */
 125   ret = curl_download_get_url ( hostname, uri, f, options, ftp );
 126   if (ret == -1 || ret == 1 || ret == -2) {
 127     g_debug("%s: download failed: curl_download_get_url=%d", __FUNCTION__, ret);
 128     failure = TRUE;
 129   }
 130
 131   if (!failure && options != NULL && options->check_file != NULL && ! options->check_file(f)) {
 132     g_debug("%s: file content checking failed", __FUNCTION__);
 133     failure = TRUE;
 134   }
 135
 136   if (failure)
 137   {
 138     g_warning(_("Download error: %s"), fn);
 139     fclose ( f );
 140     f = NULL;
 141     g_remove ( tmpfilename );
 142     g_free ( tmpfilename );
 143     g_remove ( fn ); /* couldn't create temporary. delete 0-byte file. */
 144     return -1;
 145   }
 146
 147   fclose ( f );
 148   f = NULL;
 149   g_rename ( tmpfilename, fn ); /* move completely-downloaded file to permanent location */
 150   g_free ( tmpfilename );
 151   return ret;
 152 }
 153
 154 /* success = 0, -1 = couldn't connect, -2 HTTP error, -3 file exists, -4 couldn't write to file... */
 155 /* uri: like "/uri.html?whatever" */
 156 /* only reason for the "wrapper" is so we can do redirects. */
 157 int a_http_download_get_url ( const char *hostname, const char *uri, const char *fn, DownloadOptions *opt )
 158 {
 159   return download ( hostname, uri, fn, opt, FALSE );
 160 }
 161
 162 int a_ftp_download_get_url ( const char *hostname, const char *uri, const char *fn, DownloadOptions *opt )
 163 {
 164   return download ( hostname, uri, fn, opt, TRUE );
 165 }