cmdline/apt-extracttemplates.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: apt-extracttemplates.cc,v 1.15 2003/07/26 00:00:11 mdz Exp $
   4 /* ######################################################################
   5
   6    APT Extract Templates - Program to extract debconf config and template
   7                            files
   8
   9    This is a simple program to extract config and template information
  10    from Debian packages. It can be used to speed up the preconfiguration
  11    process for debconf-enabled packages
  12
  13    ##################################################################### */
  14                                                                         /*}}}*/
  15 // Include Files                                                        /*{{{*/
  16 #include<config.h>
  17
  18 #include <apt-pkg/init.h>
  19 #include <apt-pkg/cmndline.h>
  20 #include <apt-pkg/pkgcache.h>
  21 #include <apt-pkg/cacheiterators.h>
  22 #include <apt-pkg/configuration.h>
  23 #include <apt-pkg/sourcelist.h>
  24 #include <apt-pkg/pkgcachegen.h>
  25 #include <apt-pkg/version.h>
  26 #include <apt-pkg/tagfile.h>
  27 #include <apt-pkg/debfile.h>
  28 #include <apt-pkg/deblistparser.h>
  29 #include <apt-pkg/error.h>
  30 #include <apt-pkg/strutl.h>
  31 #include <apt-pkg/fileutl.h>
  32 #include <apt-pkg/pkgsystem.h>
  33 #include <apt-pkg/dirstream.h>
  34 #include <apt-pkg/mmap.h>
  35
  36 #include <apt-private/private-cmndline.h>
  37 #include <apt-private/private-main.h>
  38
  39 #include <iostream>
  40 #include <stdio.h>
  41 #include <string.h>
  42 #include <unistd.h>
  43 #include <stdlib.h>
  44
  45 #include "apt-extracttemplates.h"
  46
  47 #include <apti18n.h>
  48                                                                         /*}}}*/
  49
  50 using namespace std;
  51
  52 pkgCache *DebFile::Cache = 0;
  53
  54 // DebFile::DebFile - Construct the DebFile object                      /*{{{*/
  55 // ---------------------------------------------------------------------
  56 /* */
  57 DebFile::DebFile(const char *debfile)
  58         : File(debfile, FileFd::ReadOnly), Control(NULL), ControlLen(0),
  59           DepOp(0), PreDepOp(0), Config(0), Template(0), Which(None)
  60 {
  61 }
  62                                                                         /*}}}*/
  63 // DebFile::~DebFile - Destruct the DebFile object                      /*{{{*/
  64 // ---------------------------------------------------------------------
  65 /* */
  66 DebFile::~DebFile()
  67 {
  68         delete [] Control;
  69         delete [] Config;
  70         delete [] Template;
  71 }
  72                                                                         /*}}}*/
  73 // DebFile::GetInstalledVer - Find out the installed version of a pkg   /*{{{*/
  74 // ---------------------------------------------------------------------
  75 /* */
  76 string DebFile::GetInstalledVer(const string &package)
  77 {
  78         pkgCache::PkgIterator Pkg = Cache->FindPkg(package);
  79         if (Pkg.end() == false)
  80         {
  81                 pkgCache::VerIterator V = Pkg.CurrentVer();
  82                 if (V.end() == false)
  83                 {
  84                         return V.VerStr();
  85                 }
  86         }
  87
  88         return string();
  89 }
  90                                                                         /*}}}*/
  91 // DebFile::Go - Start extracting a debian package                      /*{{{*/
  92 // ---------------------------------------------------------------------
  93 /* */
  94 bool DebFile::Go()
  95 {
  96         debDebFile Deb(File);
  97
  98         return Deb.ExtractTarMember(*this, "control.tar");
  99 }
 100                                                                         /*}}}*/
 101 // DebFile::DoItem examine element in package and mark                  /*{{{*/
 102 // ---------------------------------------------------------------------
 103 /* */
 104 bool DebFile::DoItem(Item &I, int &Fd)
 105 {
 106         if (strcmp(I.Name, "control") == 0)
 107         {
 108                 delete [] Control;
 109                 Control = new char[I.Size+3];
 110                 Control[I.Size] = '\n';
 111                 Control[I.Size + 1] = '\n';
 112                 Control[I.Size + 2] = '\0';
 113                 Which = IsControl;
 114                 ControlLen = I.Size + 3;
 115                 // make it call the Process method below. this is so evil
 116                 Fd = -2;
 117         }
 118         else if (strcmp(I.Name, "config") == 0)
 119         {
 120                 delete [] Config;
 121                 Config = new char[I.Size+1];
 122                 Config[I.Size] = 0;
 123                 Which = IsConfig;
 124                 Fd = -2;
 125         }
 126         else if (strcmp(I.Name, "templates") == 0)
 127         {
 128                 delete [] Template;
 129                 Template = new char[I.Size+1];
 130                 Template[I.Size] = 0;
 131                 Which = IsTemplate;
 132                 Fd = -2;
 133         }
 134         else
 135         {
 136                 // Ignore it
 137                 Fd = -1;
 138         }
 139         return true;
 140 }
 141                                                                         /*}}}*/
 142 // DebFile::Process examine element in package and copy                 /*{{{*/
 143 // ---------------------------------------------------------------------
 144 /* */
 145 bool DebFile::Process(Item &/*I*/, const unsigned char *data,
 146                 unsigned long long size, unsigned long long pos)
 147 {
 148         switch (Which)
 149         {
 150         case IsControl:
 151                 memcpy(Control + pos, data, size);
 152                 break;
 153         case IsConfig:
 154                 memcpy(Config + pos, data, size);
 155                 break;
 156         case IsTemplate:
 157                 memcpy(Template + pos, data, size);
 158                 break;
 159         default: /* throw it away */ ;
 160         }
 161         return true;
 162 }
 163                                                                         /*}}}*/
 164 // DebFile::ParseInfo - Parse control file for dependency info          /*{{{*/
 165 // ---------------------------------------------------------------------
 166 /* */
 167 bool DebFile::ParseInfo()
 168 {
 169         if (Control == NULL) return false;
 170
 171         pkgTagSection Section;
 172         if (Section.Scan(Control, ControlLen) == false)
 173                 return false;
 174
 175         Package = Section.FindS("Package");
 176         Version = GetInstalledVer(Package);
 177
 178         const char *Start, *Stop;
 179         if (Section.Find("Depends", Start, Stop) == true)
 180         {
 181                 while (1)
 182                 {
 183                         string P, V;
 184                         unsigned int Op;
 185                         Start = debListParser::ParseDepends(Start, Stop, P, V, Op);
 186                         if (Start == 0) return false;
 187                         if (P == "debconf")
 188                         {
 189                                 DepVer = V;
 190                                 DepOp = Op;
 191                                 break;
 192                         }
 193                         if (Start == Stop) break;
 194                 }
 195         }
 196
 197         if (Section.Find("Pre-Depends", Start, Stop) == true)
 198         {
 199                 while (1)
 200                 {
 201                         string P, V;
 202                         unsigned int Op;
 203                         Start = debListParser::ParseDepends(Start, Stop, P, V, Op);
 204                         if (Start == 0) return false;
 205                         if (P == "debconf")
 206                         {
 207                                 PreDepVer = V;
 208                                 PreDepOp = Op;
 209                                 break;
 210                         }
 211                         if (Start == Stop) break;
 212                 }
 213         }
 214
 215         return true;
 216 }
 217                                                                         /*}}}*/
 218 static bool ShowHelp(CommandLine &)                                     /*{{{*/
 219 {
 220         cout <<
 221                 _("Usage: apt-extracttemplates file1 [file2 ...]\n"
 222                 "\n"
 223                 "apt-extracttemplates is used to extract config and template files\n"
 224                 "from debian packages. It is used mainly by debconf(1) to prompt for\n"
 225                 "configuration questions before installation of packages.\n");
 226         return true;
 227 }
 228                                                                         /*}}}*/
 229 // WriteFile - write the contents of the passed string to a file        /*{{{*/
 230 // ---------------------------------------------------------------------
 231 /* */
 232 static string WriteFile(const char *package, const char *prefix, const char *data)
 233 {
 234         char fn[512];
 235
 236         std::string tempdir = GetTempDir();
 237         snprintf(fn, sizeof(fn), "%s/%s.%s.XXXXXX",
 238                  _config->Find("APT::ExtractTemplates::TempDir",
 239                                tempdir.c_str()).c_str(),
 240                  package, prefix);
 241         FileFd f;
 242         if (data == NULL)
 243                 data = "";
 244         int fd = mkstemp(fn);
 245         if (fd < 0) {
 246                 _error->Errno("ofstream::ofstream",_("Unable to mkstemp %s"),fn);
 247                 return string();
 248         }
 249         if (!f.OpenDescriptor(fd, FileFd::WriteOnly, FileFd::None, true))
 250         {
 251                 _error->Errno("ofstream::ofstream",_("Unable to write to %s"),fn);
 252                 return string();
 253         }
 254         f.Write(data, strlen(data));
 255         f.Close();
 256         return fn;
 257 }
 258                                                                         /*}}}*/
 259 // WriteConfig - write out the config data from a debian package file   /*{{{*/
 260 // ---------------------------------------------------------------------
 261 /* */
 262 static void WriteConfig(const DebFile &file)
 263 {
 264         string templatefile = WriteFile(file.Package.c_str(), "template", file.Template);
 265         string configscript = WriteFile(file.Package.c_str(), "config", file.Config);
 266
 267         if (templatefile.empty() == true || configscript.empty() == true)
 268                 return;
 269         cout << file.Package << " " << file.Version << " "
 270              << templatefile << " " << configscript << endl;
 271 }
 272                                                                         /*}}}*/
 273 // InitCache - initialize the package cache                             /*{{{*/
 274 // ---------------------------------------------------------------------
 275 /* */
 276 static bool Go(CommandLine &CmdL)
 277 {
 278         // Initialize the apt cache
 279         MMap *Map = 0;
 280         pkgSourceList List;
 281         List.ReadMainList();
 282         pkgCacheGenerator::MakeStatusCache(List,NULL,&Map,true);
 283         if (Map == 0)
 284            return false;
 285         DebFile::Cache = new pkgCache(Map);
 286         if (_error->PendingError() == true)
 287                 return false;
 288
 289         // Find out what version of debconf is currently installed
 290         string debconfver = DebFile::GetInstalledVer("debconf");
 291         if (debconfver.empty() == true)
 292                 return _error->Error( _("Cannot get debconf version. Is debconf installed?"));
 293
 294         // Process each package passsed in
 295         for (unsigned int I = 0; I != CmdL.FileSize(); I++)
 296         {
 297                 // Will pick up the errors later..
 298                 DebFile file(CmdL.FileList[I]);
 299                 if (file.Go() == false)
 300                 {
 301                         _error->Error("Prior errors apply to %s",CmdL.FileList[I]);
 302                         continue;
 303                 }
 304
 305                 // Does the package have templates?
 306                 if (file.Template != 0 && file.ParseInfo() == true)
 307                 {
 308                         // Check to make sure debconf dependencies are
 309                         // satisfied
 310                         // cout << "Check " << file.DepVer << ',' << debconfver << endl;
 311                         if (file.DepVer != "" &&
 312                             DebFile::Cache->VS->CheckDep(debconfver.c_str(),
 313                                         file.DepOp,file.DepVer.c_str()
 314                                                          ) == false)
 315                                 continue;
 316                         if (file.PreDepVer != "" &&
 317                             DebFile::Cache->VS->CheckDep(debconfver.c_str(),
 318                                         file.PreDepOp,file.PreDepVer.c_str()
 319                                                          ) == false)
 320                                 continue;
 321
 322                         WriteConfig(file);
 323                 }
 324         }
 325
 326
 327         delete Map;
 328         delete DebFile::Cache;
 329
 330         return !_error->PendingError();
 331 }
 332                                                                         /*}}}*/
 333 static std::vector<aptDispatchWithHelp> GetCommands()                   /*{{{*/
 334 {
 335    return {
 336         {nullptr, nullptr, nullptr}
 337    };
 338 }
 339                                                                         /*}}}*/
 340 int main(int argc, const char **argv)                                   /*{{{*/
 341 {
 342         InitLocale();
 343
 344         CommandLine CmdL;
 345         auto const Cmds = ParseCommandLine(CmdL, APT_CMD::APT_EXTRACTTEMPLATES, &_config, &_system, argc, argv, &ShowHelp, &GetCommands);
 346
 347         Go(CmdL);
 348
 349         return DispatchCommandLine(CmdL, {});
 350 }
 351                                                                         /*}}}*/