ensure transaction states are changed only once

[apt.git] / apt-pkg / edsp.h

diff --git a/apt-pkg/edsp.h b/apt-pkg/edsp.h
index 04d8c255f2c21ef76f3ca06bd8293e431325660a..2053e14e10478a335bc7e1d7e95fe8635275f052 100644 (file)
--- a/apt-pkg/edsp.h
+++ b/apt-pkg/edsp.h
@@ -1,35 +1,216 @@
 // -*- mode: cpp; mode: fold -*-
 // -*- mode: cpp; mode: fold -*-

-// Description                                                         /*{{{*/
-/* ######################################################################
+/** Description \file edsp.h                                           {{{
+   ######################################################################

    Set of methods to help writing and reading everything needed for EDSP
    Set of methods to help writing and reading everything needed for EDSP

+   with the notable exception of reading a scenario for conversion into
+   a Cache as this is handled by edsp interface for listparser and friends

    ##################################################################### */
                                                                        /*}}}*/
 #ifndef PKGLIB_EDSP_H
 #define PKGLIB_EDSP_H
 
    ##################################################################### */
                                                                        /*}}}*/
 #ifndef PKGLIB_EDSP_H
 #define PKGLIB_EDSP_H
 

-#include <apt-pkg/depcache.h>
+#include <apt-pkg/cacheset.h>
+#include <apt-pkg/pkgcache.h>
+#include <apt-pkg/cacheiterators.h>
+#include <apt-pkg/macros.h>
+
+#include <stdio.h>

 
 

+#include <list>

 #include <string>
 
 #include <string>
 

-class EDSP                                                             /*{{{*/
+#ifndef APT_8_CLEANER_HEADERS
+#include <apt-pkg/depcache.h>
+#include <apt-pkg/progress.h>
+#endif
+
+class pkgDepCache;
+class OpProgress;
+
+namespace EDSP                                                         /*{{{*/

 {
 {

-public:
-       bool static WriteRequest(pkgDepCache &Cache, FILE* output,
-                                bool const Upgrade = false,
-                                bool const DistUpgrade = false,
-                                bool const AutoRemove = false);
-       bool static WriteScenario(pkgDepCache &Cache, FILE* output);
-       bool static ReadResponse(FILE* input, pkgDepCache &Cache);
-
-       // ReadScenario is provided by the listparser infrastructure
-       bool static ReadRequest(FILE* input, std::list<std::string> &install,
-                               std::list<std::string> &remove);
-       bool static ApplyRequest(std::list<std::string> const &install,
+       /** \brief creates the EDSP request stanza
+        *
+        *  In the EDSP protocol the first thing send to the resolver is a stanza
+        *  encoding the request. This method will write this stanza by looking at
+        *  the given Cache and requests the installation of all packages which were
+        *  marked for installation in it (equally for remove).
+        *
+        *  \param Cache in which the request is encoded
+        *  \param output is written to this "file"
+        *  \param upgrade is true if it is an request like apt-get upgrade
+        *  \param distUpgrade is true if it is a request like apt-get dist-upgrade
+        *  \param autoRemove is true if removal of unneeded packages should be performed
+        *  \param Progress is an instance to report progress to
+        *
+        *  \return true if request was composed successfully, otherwise false
+        */
+       bool WriteRequest(pkgDepCache &Cache, FILE* output,
+                                bool const upgrade = false,
+                                bool const distUpgrade = false,
+                                bool const autoRemove = false,
+                               OpProgress *Progress = NULL);
+
+       /** \brief creates the scenario representing the package universe
+        *
+        *  After the request all known information about a package are send
+        *  to the solver. The output looks similar to a Packages or status file
+        *
+        *  All packages and version included in this Cache are send, even if
+        *  it doesn't make sense from an APT resolver point of view like versions
+        *  with a negative pin to enable the solver to propose even that as a
+        *  solution or at least to be able to give a hint what can be done to
+        *  statisfy a request.
+        *
+        *  \param Cache is the known package universe
+        *  \param output is written to this "file"
+        *  \param Progress is an instance to report progress to
+        *
+        *  \return true if universe was composed successfully, otherwise false
+        */
+       bool WriteScenario(pkgDepCache &Cache, FILE* output, OpProgress *Progress = NULL);
+
+       /** \brief creates a limited scenario representing the package universe
+        *
+        *  This method works similar to #WriteScenario as it works in the same
+        *  way but doesn't send the complete universe to the solver but only
+        *  packages included in the pkgset which will have only dependencies
+        *  on packages which are in the given set. All other dependencies will
+        *  be removed, so that this method can be used to create testcases
+        *
+        *  \param Cache is the known package universe
+        *  \param output is written to this "file"
+        *  \param pkgset is a set of packages the universe should be limited to
+        *  \param Progress is an instance to report progress to
+        *
+        *  \return true if universe was composed successfully, otherwise false
+        */
+       bool WriteLimitedScenario(pkgDepCache &Cache, FILE* output,
+                                        APT::PackageSet const &pkgset,
+                                        OpProgress *Progress = NULL);
+
+       /** \brief waits and acts on the information returned from the solver
+        *
+        *  This method takes care of interpreting whatever the solver sends
+        *  through the standard output like a solution, progress or an error.
+        *  The main thread should handle his control over to this method to
+        *  wait for the solver to finish the given task
+        *
+        *  \param input file descriptor with the response from the solver
+        *  \param Cache the solution should be applied on if any
+        *  \param Progress is an instance to report progress to
+        *
+        *  \return true if a solution is found and applied correctly, otherwise false
+        */
+       bool ReadResponse(int const input, pkgDepCache &Cache, OpProgress *Progress = NULL);
+
+       /** \brief search and read the request stanza for action later
+        *
+        *  This method while ignore the input up to the point it finds the
+        *  Request: line as an indicator for the Request stanza.
+        *  The request is stored in the parameters install and remove then,
+        *  as the cache isn't build yet as the scenario follows the request.
+        *
+        *  \param input file descriptor with the edsp input for the solver
+        *  \param[out] install is a list which gets populated with requested installs
+        *  \param[out] remove is a list which gets populated with requested removals
+        *  \param[out] upgrade is true if it is a request like apt-get upgrade
+        *  \param[out] distUpgrade is true if it is a request like apt-get dist-upgrade
+        *  \param[out] autoRemove is true if removal of uneeded packages should be performed
+        *
+        *  \return true if the request could be found and worked on, otherwise false
+        */
+       bool ReadRequest(int const input, std::list<std::string> &install,
+                       std::list<std::string> &remove, bool &upgrade,
+                       bool &distUpgrade, bool &autoRemove);
+
+       /** \brief takes the request lists and applies it on the cache
+        *
+        *  The lists as created by #ReadRequest will be used to find the
+        *  packages in question and mark them for install/remove.
+        *  No solving is done and no auto-install/-remove.
+        *
+        *  \param install is a list of packages to mark for installation
+        *  \param remove is a list of packages to mark for removal
+        *  \param Cache is there the markers should be set
+        *
+        *  \return false if the request couldn't be applied, true otherwise
+        */
+       bool ApplyRequest(std::list<std::string> const &install,

                                 std::list<std::string> const &remove,
                                 pkgDepCache &Cache);
                                 std::list<std::string> const &remove,
                                 pkgDepCache &Cache);

-       bool static WriteSolution(pkgDepCache &Cache, FILE* output);
-       bool static WriteError(std::string const &message, FILE* output);

 
 

-};
+       /** \brief encodes the changes in the Cache as a EDSP solution
+        *
+        *  The markers in the Cache are observed and send to given
+        *  file. The solution isn't checked for consistency or alike,
+        *  so even broken solutions can be written successfully,
+        *  but the front-end revicing it will properly fail then.
+        *
+        *  \param Cache which represents the solution
+        *  \param output to write the stanzas forming the solution to
+        *
+        *  \return true if solution could be written, otherwise false
+        */
+       bool WriteSolution(pkgDepCache &Cache, FILE* output);
+
+       /** \brief sends a progress report
+        *
+        *  \param percent of the solving completed
+        *  \param message the solver wants the user to see
+        *  \param output the front-end listens for progress report
+        */
+       bool WriteProgress(unsigned short const percent, const char* const message, FILE* output);
+
+       /** \brief sends an error report
+        *
+        *  Solvers are expected to execute successfully even if
+        *  they were unable to calculate a solution for a given task.
+        *  Obviously they can't send a solution through, so this
+        *  methods deals with formatting an error message correctly
+        *  so that the front-ends can receive and display it.
+        *
+        *  The first line of the message should be a short description
+        *  of the error so it can be used for dialog titles or alike
+        *
+        *  \param uuid of this error message
+        *  \param message is free form text to describe the error
+        *  \param output the front-end listens for error messages
+        */
+       bool WriteError(char const * const uuid, std::string const &message, FILE* output);
+
+
+       /** \brief executes the given solver and returns the pipe ends
+        *
+        *  The given solver is executed if it can be found in one of the
+        *  configured directories and setup for it is performed.
+        *
+        *  \param solver to execute
+        *  \param[out] solver_in will be the stdin of the solver
+        *  \param[out] solver_out will be the stdout of the solver
+        *
+        *  \return PID of the started solver or 0 if failure occurred
+        */
+       pid_t ExecuteSolver(const char* const solver, int * const solver_in, int * const solver_out, bool /*overload*/);
+       APT_DEPRECATED_MSG("add a dummy bool parameter to use the overload returning a pid_t") bool ExecuteSolver(const char* const solver, int *solver_in, int *solver_out);
+
+       /** \brief call an external resolver to handle the request
+        *
+        *  This method wraps all the methods above to call an external solver
+        *
+        *  \param solver to execute
+        *  \param Cache with the problem and as universe to work in
+        *  \param upgrade is true if it is a request like apt-get upgrade
+        *  \param distUpgrade is true if it is a request like apt-get dist-upgrade
+        *  \param autoRemove is true if unneeded packages should be removed
+        *  \param Progress is an instance to report progress to
+        *
+        *  \return true if the solver has successfully solved the problem,
+        *  otherwise false
+        */
+       bool ResolveExternal(const char* const solver, pkgDepCache &Cache,
+                                   bool const upgrade, bool const distUpgrade,
+                                   bool const autoRemove, OpProgress *Progress = NULL);
+}

                                                                        /*}}}*/
 #endif
                                                                        /*}}}*/
 #endif