apt-pkg/edsp.h

   1 // -*- mode: cpp; mode: fold -*-
   2 /** Description \file edsp.h                                            {{{
   3    ######################################################################
   4    Set of methods to help writing and reading everything needed for EDSP
   5    with the noteable exception of reading a scenario for conversion into
   6    a Cache as this is handled by edsp interface for listparser and friends
   7    ##################################################################### */
   8                                                                         /*}}}*/
   9 #ifndef PKGLIB_EDSP_H
  10 #define PKGLIB_EDSP_H
  11
  12 #include <apt-pkg/depcache.h>
  13 #include <apt-pkg/cacheset.h>
  14 #include <apt-pkg/progress.h>
  15
  16 #include <string>
  17
  18 class EDSP                                                              /*{{{*/
  19 {
  20         // we could use pkgCache::DepType and ::Priority, but these would be localized strings…
  21         static const char * const PrioMap[];
  22         static const char * const DepMap[];
  23
  24         bool static ReadLine(int const input, std::string &line);
  25         bool static StringToBool(char const *answer, bool const defValue);
  26
  27         void static WriteScenarioVersion(pkgDepCache &Cache, FILE* output,
  28                                          pkgCache::PkgIterator const &Pkg,
  29                                          pkgCache::VerIterator const &Ver);
  30         void static WriteScenarioDependency(pkgDepCache &Cache, FILE* output,
  31                                             pkgCache::PkgIterator const &Pkg,
  32                                             pkgCache::VerIterator const &Ver);
  33         void static WriteScenarioLimitedDependency(pkgDepCache &Cache, FILE* output,
  34                                                    pkgCache::PkgIterator const &Pkg,
  35                                                    pkgCache::VerIterator const &Ver,
  36                                                    APT::PackageSet const &pkgset);
  37 public:
  38         /** \brief creates the EDSP request stanza
  39          *
  40          *  In the EDSP protocol the first thing send to the resolver is a stanza
  41          *  encoding the request. This method will write this stanza by looking at
  42          *  the given Cache and requests the installation of all packages which were
  43          *  marked for installation in it (equally for remove).
  44          *
  45          *  \param Cache in which the request is encoded
  46          *  \param output is written to this "file"
  47          *  \param upgrade is true if it is an request like apt-get upgrade
  48          *  \param distUpgrade is true if it is a request like apt-get dist-upgrade
  49          *  \param autoRemove is true if removal of unneeded packages should be performed
  50          *  \param Progress is an instance to report progress to
  51          *
  52          *  \return true if request was composed successfully, otherwise false
  53          */
  54         bool static WriteRequest(pkgDepCache &Cache, FILE* output,
  55                                  bool const upgrade = false,
  56                                  bool const distUpgrade = false,
  57                                  bool const autoRemove = false,
  58                                 OpProgress *Progress = NULL);
  59
  60         /** \brief creates the scenario representing the package universe
  61          *
  62          *  After the request all known information about a package are send
  63          *  to the solver. The output looks similar to a Packages or status file
  64          *
  65          *  All packages and version included in this Cache are send, even if
  66          *  it doesn't make sense from an APT resolver point of view like versions
  67          *  with a negative pin to enable the solver to propose even that as a
  68          *  solution or at least to be able to give a hint what can be done to
  69          *  statisfy a request.
  70          *
  71          *  \param Cache is the known package universe
  72          *  \param output is written to this "file"
  73          *  \param Progress is an instance to report progress to
  74          *
  75          *  \return true if universe was composed successfully, otherwise false
  76          */
  77         bool static WriteScenario(pkgDepCache &Cache, FILE* output, OpProgress *Progress = NULL);
  78
  79         /** \brief creates a limited scenario representing the package universe
  80          *
  81          *  This method works similar to #WriteScenario as it works in the same
  82          *  way but doesn't send the complete universe to the solver but only
  83          *  packages included in the pkgset which will have only dependencies
  84          *  on packages which are in the given set. All other dependencies will
  85          *  be removed, so that this method can be used to create testcases
  86          *
  87          *  \param Cache is the known package universe
  88          *  \param output is written to this "file"
  89          *  \param pkgset is a set of packages the universe should be limited to
  90          *  \param Progress is an instance to report progress to
  91          *
  92          *  \return true if universe was composed successfully, otherwise false
  93          */
  94         bool static WriteLimitedScenario(pkgDepCache &Cache, FILE* output,
  95                                          APT::PackageSet const &pkgset,
  96                                          OpProgress *Progress = NULL);
  97
  98         /** \brief waits and acts on the information returned from the solver
  99          *
 100          *  This method takes care of interpreting whatever the solver sends
 101          *  through the standard output like a solution, progress or an error.
 102          *  The main thread should handle his control over to this method to
 103          *  wait for the solver to finish the given task
 104          *
 105          *  \param input file descriptor with the response from the solver
 106          *  \param Cache the solution should be applied on if any
 107          *  \param Progress is an instance to report progress to
 108          *
 109          *  \return true if a solution is found and applied correctly, otherwise false
 110          */
 111         bool static ReadResponse(int const input, pkgDepCache &Cache, OpProgress *Progress = NULL);
 112
 113         /** \brief search and read the request stanza for action later
 114          *
 115          *  This method while ignore the input up to the point it finds the
 116          *  Request: line as an indicator for the Request stanza.
 117          *  The request is stored in the parameters install and remove then,
 118          *  as the cache isn't build yet as the scenario follows the request.
 119          *
 120          *  \param input file descriptor with the edsp input for the solver
 121          *  \param[out] install is a list which gets populated with requested installs
 122          *  \param[out] remove is a list which gets populated with requested removals
 123          *  \param[out] upgrade is true if it is a request like apt-get upgrade
 124          *  \param[out] distUpgrade is true if it is a request like apt-get dist-upgrade
 125          *  \param[out] autoRemove is true if removal of uneeded packages should be performed
 126          *
 127          *  \return true if the request could be found and worked on, otherwise false
 128          */
 129         bool static ReadRequest(int const input, std::list<std::string> &install,
 130                         std::list<std::string> &remove, bool &upgrade,
 131                         bool &distUpgrade, bool &autoRemove);
 132
 133         /** \brief takes the request lists and applies it on the cache
 134          *
 135          *  The lists as created by #ReadRequest will be used to find the
 136          *  packages in question and mark them for install/remove.
 137          *  No solving is done and no auto-install/-remove.
 138          *
 139          *  \param install is a list of packages to mark for installation
 140          *  \param remove is a list of packages to mark for removal
 141          *  \param Cache is there the markers should be set
 142          *
 143          *  \return false if the request couldn't be applied, true otherwise
 144          */
 145         bool static ApplyRequest(std::list<std::string> const &install,
 146                                  std::list<std::string> const &remove,
 147                                  pkgDepCache &Cache);
 148
 149         /** \brief encodes the changes in the Cache as a EDSP solution
 150          *
 151          *  The markers in the Cache are observed and send to given
 152          *  file. The solution isn't checked for consistency or alike,
 153          *  so even broken solutions can be written successfully,
 154          *  but the front-end revicing it will properly fail then.
 155          *
 156          *  \param Cache which represents the solution
 157          *  \param output to write the stanzas forming the solution to
 158          *
 159          *  \return true if solution could be written, otherwise false
 160          */
 161         bool static WriteSolution(pkgDepCache &Cache, FILE* output);
 162
 163         /** \brief sends a progress report
 164          *
 165          *  \param percent of the solving completed
 166          *  \param message the solver wants the user to see
 167          *  \param output the front-end listens for progress report
 168          */
 169         bool static WriteProgress(unsigned short const percent, const char* const message, FILE* output);
 170
 171         /** \brief sends an error report
 172          *
 173          *  Solvers are expected to execute successfully even if
 174          *  they were unable to calculate a solution for a given task.
 175          *  Obviously they can't send a solution through, so this
 176          *  methods deals with formatting an error message correctly
 177          *  so that the front-ends can recieve and display it.
 178          *
 179          *  The first line of the message should be a short description
 180          *  of the error so it can be used for dialog titles or alike
 181          *
 182          *  \param uuid of this error message
 183          *  \param message is free form text to discribe the error
 184          *  \param output the front-end listens for error messages
 185          */
 186         bool static WriteError(char const * const uuid, std::string const &message, FILE* output);
 187
 188
 189         /** \brief executes the given solver and returns the pipe ends
 190          *
 191          *  The given solver is executed if it can be found in one of the
 192          *  configured directories and setup for it is performed.
 193          *
 194          *  \param solver to execute
 195          *  \param[out] solver_in will be the stdin of the solver
 196          *  \param[out] solver_out will be the stdout of the solver
 197          *
 198          *  \return true if the solver could be started and the pipes
 199          *  are set up correctly, otherwise false and the pipes are invalid
 200          */
 201         bool static ExecuteSolver(const char* const solver, int *solver_in, int *solver_out);
 202
 203         /** \brief call an external resolver to handle the request
 204          *
 205          *  This method wraps all the methods above to call an external solver
 206          *
 207          *  \param solver to execute
 208          *  \param Cache with the problem and as universe to work in
 209          *  \param upgrade is true if it is a request like apt-get upgrade
 210          *  \param distUpgrade is true if it is a request like apt-get dist-upgrade
 211          *  \param autoRemove is true if unneeded packages should be removed
 212          *  \param Progress is an instance to report progress to
 213          *
 214          *  \return true if the solver has successfully solved the problem,
 215          *  otherwise false
 216          */
 217         bool static ResolveExternal(const char* const solver, pkgDepCache &Cache,
 218                                     bool const upgrade, bool const distUpgrade,
 219                                     bool const autoRemove, OpProgress *Progress = NULL);
 220 };
 221                                                                         /*}}}*/
 222 #endif