- make schubi's job much easier by providing nice helper functions
[platform/upstream/libsolv.git] / src / solver.h
1 /*
2  * Copyright (c) 2007, Novell Inc.
3  *
4  * This program is licensed under the BSD license, read LICENSE.BSD
5  * for further information
6  */
7
8 /*
9  * solver.h
10  *
11  */
12
13 #ifndef SATSOLVER_SOLVER_H
14 #define SATSOLVER_SOLVER_H
15
16 #include "pooltypes.h"
17 #include "pool.h"
18 #include "repo.h"
19 #include "queue.h"
20 #include "bitmap.h"
21
22 /* ----------------------------------------------
23  * Rule
24  *
25  *   providerN(B) == Package Id of package providing tag B
26  *   N = 1, 2, 3, in case of multiple providers
27  *
28  * A requires B : !A | provider1(B) | provider2(B)
29  *
30  * A conflicts B : (!A | !provider1(B)) & (!A | !provider2(B)) ...
31  *
32  * 'not' is encoded as a negative Id
33  * 
34  * Binary rule: p = first literal, d = 0, w2 = second literal, w1 = p
35  */
36
37 typedef struct rule {
38   Id p;                 /* first literal in rule */
39   Id d;                 /* Id offset into 'list of providers terminated by 0' as used by whatprovides; pool->whatprovides + d */
40                         /* in case of binary rules, d == 0, w1 == p, w2 == other literal */
41   Id w1, w2;            /* watches, literals not-yet-decided */
42                                        /* if !w1, disabled */
43                                        /* if !w2, assertion, not rule */
44   Id n1, n2;            /* next rules in linked list, corresponding to w1,w2 */
45 } Rule;
46
47 struct solver;
48
49 typedef struct solver {
50   Pool *pool;
51   Repo *installed;
52
53   int fixsystem;                        /* repair errors in rpm dependency graph */
54   int allowdowngrade;                   /* allow to downgrade installed solvable */
55   int allowarchchange;                  /* allow to change architecture of installed solvables */
56   int allowvendorchange;                /* allow to change vendor of installed solvables */
57   int allowuninstall;                   /* allow removal of installed solvables */
58   int updatesystem;                     /* distupgrade */
59   int allowvirtualconflicts;            /* false: conflicts on package name, true: conflicts on package provides */
60   int noupdateprovide;                  /* true: update packages needs not to provide old package */
61   
62   Rule *rules;                          /* all rules */
63   Id nrules;                            /* rpm rules */
64
65   Id jobrules;                          /* user rules */
66   Id systemrules;                       /* policy rules, e.g. keep packages installed or update. All literals > 0 */
67   Id weakrules;                         /* rules that can be autodisabled */
68   Id learntrules;                       /* learnt rules */
69
70   Id *weaksystemrules;                  /* please try to install (r->d) */
71   Map noupdate;                         /* don't try to update these
72                                            installed solvables */
73
74   Id *watches;                          /* Array of rule offsets
75                                          * watches has nsolvables*2 entries and is addressed from the middle
76                                          * middle-solvable : decision to conflict, offset point to linked-list of rules
77                                          * middle+solvable : decision to install: offset point to linked-list of rules
78                                          */
79
80   Queue ruletojob;
81
82   /* our decisions: */
83   Queue decisionq;
84   Queue decisionq_why;                  /* index of rule, Offset into rules */
85   Id *decisionmap;                      /* map for all available solvables, > 0: level of decision when installed, < 0 level of decision when conflict */
86
87   /* learnt rule history */
88   Queue learnt_why;
89   Queue learnt_pool;
90
91   Queue branches;
92   int (*solution_callback)(struct solver *solv, void *data);
93   void *solution_callback_data;
94
95   int propagate_index;
96
97   Queue problems;
98   Queue suggestions;                    /* suggested packages */
99
100   Map recommendsmap;                    /* recommended packages from decisionmap */
101   Map suggestsmap;                      /* suggested packages from decisionmap */
102   int recommends_index;                 /* recommended level */
103
104   Id *obsoletes;                        /* obsoletes for each installed solvable */
105   Id *obsoletes_data;                   /* data area for obsoletes */
106
107 } Solver;
108
109 /*
110  * queue commands
111  */
112
113 typedef enum {
114   SOLVCMD_NULL=0,
115   SOLVER_INSTALL_SOLVABLE,
116   SOLVER_ERASE_SOLVABLE,
117   SOLVER_INSTALL_SOLVABLE_NAME,
118   SOLVER_ERASE_SOLVABLE_NAME,
119   SOLVER_INSTALL_SOLVABLE_PROVIDES,
120   SOLVER_ERASE_SOLVABLE_PROVIDES,
121   SOLVER_INSTALL_SOLVABLE_UPDATE
122 } SolverCmd;
123
124 typedef enum {
125   SOLVER_PROBLEM_UPDATE_RULE,
126   SOLVER_PROBLEM_JOB_RULE,
127   SOLVER_PROBLEM_JOB_NOTHING_PROVIDES_DEP,
128   SOLVER_PROBLEM_NOT_INSTALLABLE,
129   SOLVER_PROBLEM_NOTHING_PROVIDES_DEP,
130   SOLVER_PROBLEM_SAME_NAME,
131   SOLVER_PROBLEM_PACKAGE_CONFLICT,
132   SOLVER_PROBLEM_PACKAGE_OBSOLETES,
133   SOLVER_PROBLEM_DEP_PROVIDERS_NOT_INSTALLABLE
134 } SolverProbleminfo;
135
136
137 extern Solver *solver_create(Pool *pool, Repo *installed);
138 extern void solver_free(Solver *solv);
139 extern void solver_solve(Solver *solv, Queue *job);
140 extern int solver_dep_installed(Solver *solv, Id dep);
141
142 extern Id solver_next_problem(Solver *solv, Id problem);
143 extern Id solver_next_solution(Solver *solv, Id problem, Id solution);
144 extern Id solver_next_solutionelement(Solver *solv, Id problem, Id solution, Id element, Id *p, Id *rp);
145 extern SolverProbleminfo solver_problemruleinfo(Solver *solv, Queue *job, Id rid, Id *depp, Id *sourcep, Id *targetp);
146 extern Id findproblemrule(Solver *solv, Id problem);
147
148 /* debug functions, do not use */
149 void printdecisions(Solver *solv);
150 void printsolutions(Solver *solv, Queue *job);
151
152
153 static inline int
154 solver_dep_fulfilled(Solver *solv, Id dep)
155 {
156   Pool *pool = solv->pool;
157   Id p, *pp;
158
159   if (ISRELDEP(dep))
160     {
161       Reldep *rd = GETRELDEP(pool, dep);
162       if (rd->flags == REL_AND)
163         {
164           if (!solver_dep_fulfilled(solv, rd->name))
165             return 0;
166           return solver_dep_fulfilled(solv, rd->evr);
167         }
168       if (rd->flags == REL_NAMESPACE && rd->name == NAMESPACE_INSTALLED)
169         return solver_dep_installed(solv, rd->evr);
170     }
171   FOR_PROVIDES(p, pp, dep)
172     {
173       if (solv->decisionmap[p] > 0)
174         return 1;
175     }
176   return 0;
177 }
178
179 static inline int
180 solver_is_supplementing(Solver *solv, Solvable *s)
181 {
182   Id sup, *supp;
183   if (!s->supplements && !s->freshens)
184     return 0;
185   if (s->supplements)
186     {
187       supp = s->repo->idarraydata + s->supplements;
188       while ((sup = *supp++) != 0)
189         if (solver_dep_fulfilled(solv, sup))
190           break;
191       if (!sup)
192         return 0;
193     }
194   if (s->freshens)
195     {
196       supp = s->repo->idarraydata + s->freshens;
197       while ((sup = *supp++) != 0)
198         if (solver_dep_fulfilled(solv, sup))
199           break;
200       if (!sup)
201         return 0;
202     }
203   return 1;
204 }
205
206 static inline int
207 solver_is_enhancing(Solver *solv, Solvable *s)
208 {
209   Id enh, *enhp;
210   if (!s->enhances)
211     return 0;
212   enhp = s->repo->idarraydata + s->enhances;
213   while ((enh = *enhp++) != 0)
214     if (solver_dep_fulfilled(solv, enh))
215       return 1;
216   return 0;
217 }
218
219 #endif /* SATSOLVER_SOLVER_H */