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 "mirror.h"
  29 #include "http.h"
  30 #include "apti18n.h"
  31                                                                         /*}}}*/
  32
  33 /* Done:
  34  * - works with http (only!)
  35  * - always picks the first mirror from the list
  36  * - call out to problem reporting script
  37  * - supports "deb mirror://host/path/to/mirror-list/// dist component"
  38  * - uses pkgAcqMethod::FailReason() to have a string representation
  39  *   of the failure that is also send to LP
  40  *
  41  * TODO:
  42  * - deal with runing as non-root because we can't write to the lists
  43      dir then -> use the cached mirror file
  44  * - better method to download than having a pkgAcquire interface here
  45  *   and better error handling there!
  46  * - support more than http
  47  * - testing :)
  48  */
  49
  50 MirrorMethod::MirrorMethod()
  51    : HttpMethod(), DownloadedMirrorFile(false)
  52 {
  53 };
  54
  55 // HttpMethod::Configuration - Handle a configuration message           /*{{{*/
  56 // ---------------------------------------------------------------------
  57 /* We stash the desired pipeline depth */
  58 bool MirrorMethod::Configuration(string Message)
  59 {
  60    if (pkgAcqMethod::Configuration(Message) == false)
  61       return false;
  62    Debug = _config->FindB("Debug::Acquire::mirror",false);
  63
  64    return true;
  65 }
  66                                                                         /*}}}*/
  67
  68 // clean the mirrors dir based on ttl information
  69 bool MirrorMethod::Clean(string Dir)
  70 {
  71    vector<metaIndex *>::const_iterator I;
  72
  73    if(Debug)
  74       clog << "MirrorMethod::Clean(): " << Dir << endl;
  75
  76    if(Dir == "/")
  77       return _error->Error("will not clean: '/'");
  78
  79    // read sources.list
  80    pkgSourceList list;
  81    list.ReadMainList();
  82
  83    DIR *D = opendir(Dir.c_str());
  84    if (D == 0)
  85       return _error->Errno("opendir",_("Unable to read %s"),Dir.c_str());
  86
  87    string StartDir = SafeGetCWD();
  88    if (chdir(Dir.c_str()) != 0)
  89    {
  90       closedir(D);
  91       return _error->Errno("chdir",_("Unable to change to %s"),Dir.c_str());
  92    }
  93
  94    for (struct dirent *Dir = readdir(D); Dir != 0; Dir = readdir(D))
  95    {
  96       // Skip some files..
  97       if (strcmp(Dir->d_name,"lock") == 0 ||
  98           strcmp(Dir->d_name,"partial") == 0 ||
  99           strcmp(Dir->d_name,".") == 0 ||
 100           strcmp(Dir->d_name,"..") == 0)
 101          continue;
 102
 103       // see if we have that uri
 104       for(I=list.begin(); I != list.end(); I++)
 105       {
 106          string uri = (*I)->GetURI();
 107          if(uri.substr(0,strlen("mirror://")) != string("mirror://"))
 108             continue;
 109          string BaseUri = uri.substr(0,uri.size()-1);
 110          if (URItoFileName(BaseUri) == Dir->d_name)
 111             break;
 112       }
 113       // nothing found, nuke it
 114       if (I == list.end())
 115          unlink(Dir->d_name);
 116    };
 117
 118    chdir(StartDir.c_str());
 119    closedir(D);
 120    return true;
 121 }
 122
 123
 124 bool MirrorMethod::DownloadMirrorFile(string mirror_uri_str)
 125 {
 126
 127    // check the file, if it is not older than RefreshInterval just use it
 128    // otherwise try to get a new one
 129    if(FileExists(MirrorFile))
 130    {
 131       struct stat buf;
 132       time_t t,now,refresh;
 133       if(stat(MirrorFile.c_str(), &buf) != 0)
 134          return false;
 135       t = std::max(buf.st_mtime, buf.st_ctime);
 136       now = time(NULL);
 137       refresh = 60*_config->FindI("Acquire::Mirror::RefreshInterval",360);
 138       if(t + refresh > now)
 139       {
 140          if(Debug)
 141             clog << "Mirror file is in RefreshInterval" << endl;
 142          DownloadedMirrorFile = true;
 143          return true;
 144       }
 145       if(Debug)
 146          clog << "Mirror file " << MirrorFile << " older than " << refresh << "min, re-download it" << endl;
 147    }
 148
 149    // not that great to use pkgAcquire here, but we do not have
 150    // any other way right now
 151    string fetch = BaseUri;
 152    fetch.replace(0,strlen("mirror://"),"http://");
 153
 154    pkgAcquire Fetcher;
 155    new pkgAcqFile(&Fetcher, fetch, "", 0, "", "", "", MirrorFile);
 156    bool res = (Fetcher.Run() == pkgAcquire::Continue);
 157    if(res)
 158       DownloadedMirrorFile = true;
 159    Fetcher.Shutdown();
 160    return res;
 161 }
 162
 163 bool MirrorMethod::SelectMirror()
 164 {
 165    // if we do not have a MirrorFile, fallback
 166    if(!FileExists(MirrorFile))
 167    {
 168       // FIXME: fallback to a default mirror here instead
 169       //        and provide a config option to define that default
 170       return _error->Error(_("No mirror file '%s' found "), MirrorFile.c_str());
 171    }
 172
 173    // FIXME: make the mirror selection more clever, do not
 174    //        just use the first one!
 175    // BUT: we can not make this random, the mirror has to be
 176    //      stable accross session, because otherwise we can
 177    //      get into sync issues (got indexfiles from mirror A,
 178    //      but packages from mirror B - one might be out of date etc)
 179    ifstream in(MirrorFile.c_str());
 180    getline(in, Mirror);
 181    if(Debug)
 182       cerr << "Using mirror: " << Mirror << endl;
 183
 184    UsedMirror = Mirror;
 185    return true;
 186 }
 187
 188 string MirrorMethod::GetMirrorFileName(string mirror_uri_str)
 189 {
 190    /*
 191     - a mirror_uri_str looks like this:
 192     mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors/dists/feisty/Release.gpg
 193
 194     - the matching source.list entry
 195     deb mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors feisty main
 196
 197     - we actually want to go after:
 198     http://people.ubuntu.com/~mvo/apt/mirror/mirrors
 199
 200     And we need to save the BaseUri for later:
 201     - mirror://people.ubuntu.com/~mvo/apt/mirror/mirrors
 202
 203    FIXME: what if we have two similar prefixes?
 204      mirror://people.ubuntu.com/~mvo/mirror
 205      mirror://people.ubuntu.com/~mvo/mirror2
 206    then mirror_uri_str looks like:
 207      mirror://people.ubuntu.com/~mvo/apt/mirror/dists/feisty/Release.gpg
 208      mirror://people.ubuntu.com/~mvo/apt/mirror2/dists/feisty/Release.gpg
 209    we search sources.list and find:
 210      mirror://people.ubuntu.com/~mvo/apt/mirror
 211    in both cases! So we need to apply some domain knowledge here :( and
 212    check for /dists/ or /Release.gpg as suffixes
 213    */
 214    string name;
 215    if(Debug)
 216       std::cerr << "GetMirrorFileName: " << mirror_uri_str << std::endl;
 217
 218    // read sources.list and find match
 219    vector<metaIndex *>::const_iterator I;
 220    pkgSourceList list;
 221    list.ReadMainList();
 222    for(I=list.begin(); I != list.end(); I++)
 223    {
 224       string uristr = (*I)->GetURI();
 225       if(Debug)
 226          std::cerr << "Checking: " << uristr << std::endl;
 227       if(uristr.substr(0,strlen("mirror://")) != string("mirror://"))
 228          continue;
 229       // find matching uri in sources.list
 230       if(mirror_uri_str.substr(0,uristr.size()) == uristr)
 231       {
 232          if(Debug)
 233             std::cerr << "found BaseURI: " << uristr << std::endl;
 234          BaseUri = uristr.substr(0,uristr.size()-1);
 235       }
 236    }
 237    // get new file
 238    name = _config->FindDir("Dir::State::mirrors") + URItoFileName(BaseUri);
 239
 240    if(Debug)
 241    {
 242       cerr << "base-uri: " << BaseUri << endl;
 243       cerr << "mirror-file: " << name << endl;
 244    }
 245    return name;
 246 }
 247
 248 // MirrorMethod::Fetch - Fetch an item                                  /*{{{*/
 249 // ---------------------------------------------------------------------
 250 /* This adds an item to the pipeline. We keep the pipeline at a fixed
 251    depth. */
 252 bool MirrorMethod::Fetch(FetchItem *Itm)
 253 {
 254    // the http method uses Fetch(0) as a way to update the pipeline,
 255    // just let it do its work in this case - Fetch() with a valid
 256    // Itm will always run before the first Fetch(0)
 257    if(Itm == NULL)
 258       return HttpMethod::Fetch(Itm);
 259
 260    // if we don't have the name of the mirror file on disk yet,
 261    // calculate it now (can be derived from the uri)
 262    if(MirrorFile.empty())
 263       MirrorFile = GetMirrorFileName(Itm->Uri);
 264
 265   // download mirror file once (if we are after index files)
 266    if(Itm->IndexFile && !DownloadedMirrorFile)
 267    {
 268       Clean(_config->FindDir("Dir::State::mirrors"));
 269       DownloadMirrorFile(Itm->Uri);
 270    }
 271
 272    if(Mirror.empty())
 273       SelectMirror();
 274
 275    for (FetchItem *I = Queue; I != 0; I = I->Next)
 276    {
 277       if(I->Uri.find("mirror://") != string::npos)
 278          I->Uri.replace(0,BaseUri.size(), Mirror);
 279    }
 280
 281    // now run the real fetcher
 282    return HttpMethod::Fetch(Itm);
 283 };
 284
 285 void MirrorMethod::Fail(string Err,bool Transient)
 286 {
 287    if(Queue->Uri.find("http://") != string::npos)
 288       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 289    pkgAcqMethod::Fail(Err, Transient);
 290 }
 291
 292 void MirrorMethod::URIStart(FetchResult &Res)
 293 {
 294    if(Queue->Uri.find("http://") != string::npos)
 295       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 296    pkgAcqMethod::URIStart(Res);
 297 }
 298
 299 void MirrorMethod::URIDone(FetchResult &Res,FetchResult *Alt)
 300 {
 301    if(Queue->Uri.find("http://") != string::npos)
 302       Queue->Uri.replace(0,Mirror.size(), BaseUri);
 303    pkgAcqMethod::URIDone(Res, Alt);
 304 }
 305
 306
 307 int main()
 308 {
 309    setlocale(LC_ALL, "");
 310
 311    MirrorMethod Mth;
 312
 313    return Mth.Loop();
 314 }
 315
 316