methods/mirror.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: mirror.cc,v 1.59 2004/05/08 19:42:35 mdz Exp $
   4 /* ######################################################################
   5
   6    Mirror Aquire Method - This is the Mirror aquire method for APT.
   7
   8    ##################################################################### */
   9                                                                         /*}}}*/
  10 // Include Files                                                        /*{{{*/
  11 #include <apt-pkg/fileutl.h>
  12 #include <apt-pkg/acquire-method.h>
  13 #include <apt-pkg/acquire-item.h>
  14 #include <apt-pkg/acquire.h>
  15 #include <apt-pkg/error.h>
  16 #include <apt-pkg/hashes.h>
  17 #include <apt-pkg/sourcelist.h>
  18
  19 #include <fstream>
  20 #include <iostream>
  21 #include <stdarg.h>
  22 #include <sys/stat.h>
  23 #include <sys/types.h>
  24 #include <dirent.h>
  25
  26 using namespace std;
  27
  28 #include<sstream>
  29
  30 #include "mirror.h"
  31 #include "http.h"
  32 #include "apti18n.h"
  33                                                                         /*}}}*/
  34
  35 /* Done:
  36  * - works with http (only!)
  37  * - always picks the first mirror from the list
  38  * - call out to problem reporting script
  39  * - supports "deb mirror://host/path/to/mirror-list/// dist component"
  40  * - uses pkgAcqMethod::FailReason() to have a string representation
  41  *   of the failure that is also send to LP
  42  *
  43  * TODO:
  44  * - deal with runing as non-root because we can't write to the lists
  45      dir then -> use the cached mirror file
  46  * - better method to download than having a pkgAcquire interface here
  47  *   and better error handling there!
  48  * - support more than http
  49  * - testing :)
  50  */
  51
  52 MirrorMethod::MirrorMethod()
  53    : HttpMethod(), DownloadedMirrorFile(false)
  54 {
  55 };
  56
  57 // HttpMethod::Configuration - Handle a configuration message           /*{{{*/
  58 // ---------------------------------------------------------------------
  59 /* We stash the desired pipeline depth */
  60 bool MirrorMethod::Configuration(string Message)
  61 {
  62    if (pkgAcqMethod::Configuration(Message) == false)
  63       return false;
  64    Debug = _config->FindB("Debug::Acquire::mirror",false);
  65
  66    return true;
  67 }
  68                                                                         /*}}}*/
  69
  70 // clean the mirrors dir based on ttl information
  71 bool MirrorMethod::Clean(string Dir)
  72 {
  73    vector<metaIndex *>::const_iterator I;
  74
  75    if(Debug)
  76       clog << "MirrorMethod::Clean(): " << Dir << endl;
  77
  78    if(Dir == "/")
  79       return _error->Error("will not clean: '/'");
  80
  81    // read sources.list
  82    pkgSourceList list;
  83    list.ReadMainList();
  84
  85    DIR *D = opendir(Dir.c_str());
  86    if (D == 0)
  87       return _error->Errno("opendir",_("Unable to read %s"),Dir.c_str());
  88
  89    string StartDir = SafeGetCWD();
  90    if (chdir(Dir.c_str()) != 0)
  91    {
  92       closedir(D);
  93       return _error->Errno("chdir",_("Unable to change to %s"),Dir.c_str());
  94    }
  95
  96    for (struct dirent *Dir = readdir(D); Dir != 0; Dir = readdir(D))
  97    {
  98       // Skip some files..
  99       if (strcmp(Dir->d_name,"lock") == 0 ||
 100           strcmp(Dir->d_name,"partial") == 0 ||
 101           strcmp(Dir->d_name,".") == 0 ||
 102           strcmp(Dir->d_name,"..") == 0)
 103          continue;
 104
 105       // see if we have that uri
 106       for(I=list.begin(); I != list.end(); I++)
 107       {
 108          string uri = (*I)->GetURI();
 109          if(uri.substr(0,strlen("mirror://")) != string("mirror://"))
 110             continue;
 111          string BaseUri = uri.substr(0,uri.size()-1);
 112          if (URItoFileName(BaseUri) == Dir->d_name)
 113             break;
 114       }
 115       // nothing found, nuke it
 116       if (I == list.end())
 117          unlink(Dir->d_name);
 118    };
 119
 120    chdir(StartDir.c_str());
 121    closedir(D);
 122    return true;
 123 }
 124
 125
 126 bool MirrorMethod::DownloadMirrorFile(string mirror_uri_str)
 127 {
 128    if(Debug)
 129       clog << "MirrorMethod::DownloadMirrorFile(): " << endl;
 130
 131    // not that great to use pkgAcquire here, but we do not have
 132    // any other way right now
 133    string fetch = BaseUri;
 134    fetch.replace(0,strlen("mirror://"),"http://");
 135
 136    pkgAcquire Fetcher;
 137    new pkgAcqFile(&Fetcher, fetch, "", 0, "", "", "", MirrorFile);
 138    bool res = (Fetcher.Run() == pkgAcquire::Continue);
 139    if(res)
 140       DownloadedMirrorFile = true;
 141    Fetcher.Shutdown();
 142    return res;
 143 }
 144
 145 bool MirrorMethod::SelectNextMirror()
 146 {
 147    if(Debug)
 148       cerr << "using mirror: " << Mirror << endl;
 149
 150    Mirror = AllMirrors[0];
 151    UsedMirror = Mirror;
 152    return false;
 153 }
 154
 155 bool MirrorMethod::InitMirrors()
 156 {
 157    // if we do not have a MirrorFile, fallback
 158    if(!FileExists(MirrorFile))
 159    {
 160       // FIXME: fallback to a default mirror here instead
 161       //        and provide a config option to define that default
 162       return _error->Error(_("No mirror file '%s' found "), MirrorFile.c_str());
 163    }
 164
 165    // FIXME: make the mirror selection more clever, do not
 166    //        just use the first one!
 167    // BUT: we can not make this random, the mirror has to be
 168    //      stable accross session, because otherwise we can
 169    //      get into sync issues (got indexfiles from mirror A,
 170    //      but packages from mirror B - one might be out of date etc)
 171    ifstream in(MirrorFile.c_str());
 172    string s;
 173    while (!in.eof())
 174    {
 175       getline(in, s);
 176       if (s.size() > 0)
 177          AllMirrors.push_back(s);
 178    }
 179    SelectNextMirror();
 180    return true;
 181 }
 182
 183 string MirrorMethod::GetMirrorFileName(string mirror_uri_str)
 184 {
 185    /*
 186     - a mirror_uri_str looks like this:
 187     mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors/dists/feisty/Release.gpg
 188
 189     - the matching source.list entry
 190     deb mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors feisty main
 191
 192     - we actually want to go after:
 193     http://people.ubuntu.com/~mvo/apt/mirror/mirrors
 194
 195     And we need to save the BaseUri for later:
 196     - mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors
 197
 198    FIXME: what if we have two similar prefixes?
 199      mirror://people.ubuntu.com/~mvo/mirror
 200      mirror://people.ubuntu.com/~mvo/mirror2
 201    then mirror_uri_str looks like:
 202      mirror://people.ubuntu.com/~mvo/apt/mirror/dists/feisty/Release.gpg
 203      mirror://people.ubuntu.com/~mvo/apt/mirror2/dists/feisty/Release.gpg
 204    we search sources.list and find:
 205      mirror://people.ubuntu.com/~mvo/apt/mirror
 206    in both cases! So we need to apply some domain knowledge here :( and
 207    check for /dists/ or /Release.gpg as suffixes
 208    */
 209    string name;
 210    if(Debug)
 211       std::cerr << "GetMirrorFileName: " << mirror_uri_str << std::endl;
 212
 213    // read sources.list and find match
 214    vector<metaIndex *>::const_iterator I;
 215    pkgSourceList list;
 216    list.ReadMainList();
 217    for(I=list.begin(); I != list.end(); I++)
 218    {
 219       string uristr = (*I)->GetURI();
 220       if(Debug)
 221          std::cerr << "Checking: " << uristr << std::endl;
 222       if(uristr.substr(0,strlen("mirror://")) != string("mirror://"))
 223          continue;
 224       // find matching uri in sources.list
 225       if(mirror_uri_str.substr(0,uristr.size()) == uristr)
 226       {
 227          if(Debug)
 228             std::cerr << "found BaseURI: " << uristr << std::endl;
 229          BaseUri = uristr.substr(0,uristr.size()-1);
 230       }
 231    }
 232    // get new file
 233    name = _config->FindDir("Dir::State::mirrors") + URItoFileName(BaseUri);
 234
 235    if(Debug)
 236    {
 237       cerr << "base-uri: " << BaseUri << endl;
 238       cerr << "mirror-file: " << name << endl;
 239    }
 240    return name;
 241 }
 242
 243 // MirrorMethod::Fetch - Fetch an item                                  /*{{{*/
 244 // ---------------------------------------------------------------------
 245 /* This adds an item to the pipeline. We keep the pipeline at a fixed
 246    depth. */
 247 bool MirrorMethod::Fetch(FetchItem *Itm)
 248 {
 249    if(Debug)
 250       clog << "MirrorMethod::Fetch()" << endl;
 251
 252    // the http method uses Fetch(0) as a way to update the pipeline,
 253    // just let it do its work in this case - Fetch() with a valid
 254    // Itm will always run before the first Fetch(0)
 255    if(Itm == NULL)
 256       return HttpMethod::Fetch(Itm);
 257
 258    // if we don't have the name of the mirror file on disk yet,
 259    // calculate it now (can be derived from the uri)
 260    if(MirrorFile.empty())
 261       MirrorFile = GetMirrorFileName(Itm->Uri);
 262
 263   // download mirror file once (if we are after index files)
 264    if(Itm->IndexFile && !DownloadedMirrorFile)
 265    {
 266       Clean(_config->FindDir("Dir::State::mirrors"));
 267       DownloadMirrorFile(Itm->Uri);
 268    }
 269
 270    if(Mirror.empty()) {
 271       if(!InitMirrors()) {
 272          // no valid mirror selected, something went wrong downloading
 273          // from the master mirror site most likely and there is
 274          // no old mirror file availalbe
 275          return false;
 276       }
 277    }
 278    if(Debug)
 279       clog << "selected mirror: " << Mirror << endl;
 280
 281
 282    for (FetchItem *I = Queue; I != 0; I = I->Next)
 283    {
 284       if(I->Uri.find("mirror://") != string::npos)
 285          I->Uri.replace(0,BaseUri.size(), Mirror);
 286    }
 287
 288    // now run the real fetcher
 289    return HttpMethod::Fetch(Itm);
 290 };
 291
 292 void MirrorMethod::Fail(string Err,bool Transient)
 293 {
 294    // try the next mirror on fail
 295    string old_mirror = Mirror;
 296    if (SelectNextMirror())
 297    {
 298       Queue->Uri.replace(0, old_mirror.size(), Mirror);
 299       return;
 300    }
 301
 302    // all mirrors failed, so bail out
 303    string s;
 304    strprintf(s, _("[Mirror: %s]"), Mirror.c_str());
 305    SetIP(s);
 306
 307    if(Queue->Uri.find("http://") != string::npos)
 308       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 309    pkgAcqMethod::Fail(Err, Transient);
 310 }
 311
 312 void MirrorMethod::URIStart(FetchResult &Res)
 313 {
 314    if(Queue->Uri.find("http://") != string::npos)
 315       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 316    pkgAcqMethod::URIStart(Res);
 317 }
 318
 319 void MirrorMethod::URIDone(FetchResult &Res,FetchResult *Alt)
 320 {
 321    if(Queue->Uri.find("http://") != string::npos)
 322       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 323    pkgAcqMethod::URIDone(Res, Alt);
 324 }
 325
 326
 327 int main()
 328 {
 329    setlocale(LC_ALL, "");
 330
 331    MirrorMethod Mth;
 332
 333    return Mth.Loop();
 334 }
 335
 336