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    // check the file, if it is not older than RefreshInterval just use it
 132    // otherwise try to get a new one
 133    if(FileExists(MirrorFile))
 134    {
 135       struct stat buf;
 136       time_t t,now,refresh;
 137       if(stat(MirrorFile.c_str(), &buf) != 0)
 138          return false;
 139       t = std::max(buf.st_mtime, buf.st_ctime);
 140       now = time(NULL);
 141       refresh = 60*_config->FindI("Acquire::Mirror::RefreshInterval",360);
 142       if(t + refresh > now)
 143       {
 144          if(Debug)
 145             clog << "Mirror file is in RefreshInterval" << endl;
 146          DownloadedMirrorFile = true;
 147          return true;
 148       }
 149       if(Debug)
 150          clog << "Mirror file " << MirrorFile << " older than " << refresh << "min, re-download it" << endl;
 151    }
 152
 153    // not that great to use pkgAcquire here, but we do not have
 154    // any other way right now
 155    string fetch = BaseUri;
 156    fetch.replace(0,strlen("mirror://"),"http://");
 157
 158    pkgAcquire Fetcher;
 159    new pkgAcqFile(&Fetcher, fetch, "", 0, "", "", "", MirrorFile);
 160    bool res = (Fetcher.Run() == pkgAcquire::Continue);
 161    if(res)
 162       DownloadedMirrorFile = true;
 163    Fetcher.Shutdown();
 164    return res;
 165 }
 166
 167 bool MirrorMethod::SelectNextMirror()
 168 {
 169    if(Debug)
 170       cerr << "using mirror: " << Mirror << endl;
 171
 172    Mirror = AllMirrors[0];
 173    UsedMirror = Mirror;
 174    return false;
 175 }
 176
 177 bool MirrorMethod::InitMirrors()
 178 {
 179    // if we do not have a MirrorFile, fallback
 180    if(!FileExists(MirrorFile))
 181    {
 182       // FIXME: fallback to a default mirror here instead
 183       //        and provide a config option to define that default
 184       return _error->Error(_("No mirror file '%s' found "), MirrorFile.c_str());
 185    }
 186
 187    // FIXME: make the mirror selection more clever, do not
 188    //        just use the first one!
 189    // BUT: we can not make this random, the mirror has to be
 190    //      stable accross session, because otherwise we can
 191    //      get into sync issues (got indexfiles from mirror A,
 192    //      but packages from mirror B - one might be out of date etc)
 193    ifstream in(MirrorFile.c_str());
 194    string s;
 195    while (!in.eof())
 196    {
 197       getline(in, s);
 198       if (s.size() > 0)
 199          AllMirrors.push_back(s);
 200    }
 201    SelectNextMirror();
 202    return true;
 203 }
 204
 205 string MirrorMethod::GetMirrorFileName(string mirror_uri_str)
 206 {
 207    /*
 208     - a mirror_uri_str looks like this:
 209     mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors/dists/feisty/Release.gpg
 210
 211     - the matching source.list entry
 212     deb mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors feisty main
 213
 214     - we actually want to go after:
 215     http://people.ubuntu.com/~mvo/apt/mirror/mirrors
 216
 217     And we need to save the BaseUri for later:
 218     - mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors
 219
 220    FIXME: what if we have two similar prefixes?
 221      mirror://people.ubuntu.com/~mvo/mirror
 222      mirror://people.ubuntu.com/~mvo/mirror2
 223    then mirror_uri_str looks like:
 224      mirror://people.ubuntu.com/~mvo/apt/mirror/dists/feisty/Release.gpg
 225      mirror://people.ubuntu.com/~mvo/apt/mirror2/dists/feisty/Release.gpg
 226    we search sources.list and find:
 227      mirror://people.ubuntu.com/~mvo/apt/mirror
 228    in both cases! So we need to apply some domain knowledge here :( and
 229    check for /dists/ or /Release.gpg as suffixes
 230    */
 231    string name;
 232    if(Debug)
 233       std::cerr << "GetMirrorFileName: " << mirror_uri_str << std::endl;
 234
 235    // read sources.list and find match
 236    vector<metaIndex *>::const_iterator I;
 237    pkgSourceList list;
 238    list.ReadMainList();
 239    for(I=list.begin(); I != list.end(); I++)
 240    {
 241       string uristr = (*I)->GetURI();
 242       if(Debug)
 243          std::cerr << "Checking: " << uristr << std::endl;
 244       if(uristr.substr(0,strlen("mirror://")) != string("mirror://"))
 245          continue;
 246       // find matching uri in sources.list
 247       if(mirror_uri_str.substr(0,uristr.size()) == uristr)
 248       {
 249          if(Debug)
 250             std::cerr << "found BaseURI: " << uristr << std::endl;
 251          BaseUri = uristr.substr(0,uristr.size()-1);
 252       }
 253    }
 254    // get new file
 255    name = _config->FindDir("Dir::State::mirrors") + URItoFileName(BaseUri);
 256
 257    if(Debug)
 258    {
 259       cerr << "base-uri: " << BaseUri << endl;
 260       cerr << "mirror-file: " << name << endl;
 261    }
 262    return name;
 263 }
 264
 265 // MirrorMethod::Fetch - Fetch an item                                  /*{{{*/
 266 // ---------------------------------------------------------------------
 267 /* This adds an item to the pipeline. We keep the pipeline at a fixed
 268    depth. */
 269 bool MirrorMethod::Fetch(FetchItem *Itm)
 270 {
 271    if(Debug)
 272       clog << "MirrorMethod::Fetch()" << endl;
 273
 274    // the http method uses Fetch(0) as a way to update the pipeline,
 275    // just let it do its work in this case - Fetch() with a valid
 276    // Itm will always run before the first Fetch(0)
 277    if(Itm == NULL)
 278       return HttpMethod::Fetch(Itm);
 279
 280    // if we don't have the name of the mirror file on disk yet,
 281    // calculate it now (can be derived from the uri)
 282    if(MirrorFile.empty())
 283       MirrorFile = GetMirrorFileName(Itm->Uri);
 284
 285   // download mirror file once (if we are after index files)
 286    if(Itm->IndexFile && !DownloadedMirrorFile)
 287    {
 288       Clean(_config->FindDir("Dir::State::mirrors"));
 289       DownloadMirrorFile(Itm->Uri);
 290    }
 291
 292    if(Mirror.empty()) {
 293       if(!InitMirrors()) {
 294          // no valid mirror selected, something went wrong downloading
 295          // from the master mirror site most likely and there is
 296          // no old mirror file availalbe
 297          return false;
 298       }
 299    }
 300    if(Debug)
 301       clog << "selected mirror: " << Mirror << endl;
 302
 303
 304    for (FetchItem *I = Queue; I != 0; I = I->Next)
 305    {
 306       if(I->Uri.find("mirror://") != string::npos)
 307          I->Uri.replace(0,BaseUri.size(), Mirror);
 308    }
 309
 310    // now run the real fetcher
 311    return HttpMethod::Fetch(Itm);
 312 };
 313
 314 void MirrorMethod::Fail(string Err,bool Transient)
 315 {
 316    // try the next mirror on fail
 317    string old_mirror = Mirror;
 318    if (SelectNextMirror())
 319    {
 320       Queue->Uri.replace(0, old_mirror.size(), Mirror);
 321       return;
 322    }
 323
 324    // all mirrors failed, so bail out
 325    string s;
 326    strprintf(s, _("[Mirror: %s]"), Mirror.c_str());
 327    SetIP(s);
 328
 329    if(Queue->Uri.find("http://") != string::npos)
 330       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 331    pkgAcqMethod::Fail(Err, Transient);
 332 }
 333
 334 void MirrorMethod::URIStart(FetchResult &Res)
 335 {
 336    if(Queue->Uri.find("http://") != string::npos)
 337       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 338    pkgAcqMethod::URIStart(Res);
 339 }
 340
 341 void MirrorMethod::URIDone(FetchResult &Res,FetchResult *Alt)
 342 {
 343    if(Queue->Uri.find("http://") != string::npos)
 344       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 345    pkgAcqMethod::URIDone(Res, Alt);
 346 }
 347
 348
 349 int main()
 350 {
 351    setlocale(LC_ALL, "");
 352
 353    MirrorMethod Mth;
 354
 355    return Mth.Loop();
 356 }
 357
 358