1 /*****************************************************************************************[Main.cc]
2 Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
3 Copyright (c) 2007-2010, Niklas Sorensson
4 
5 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
6 associated documentation files (the "Software"), to deal in the Software without restriction,
7 including without limitation the rights to use, copy, modify, merge, publish, distribute,
8 sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
9 furnished to do so, subject to the following conditions:
10 
11 The above copyright notice and this permission notice shall be included in all copies or
12 substantial portions of the Software.
13 
14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
15 NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
16 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
17 DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
18 OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
19 **************************************************************************************************/
20 
21 #include <errno.h>
22 
23 #include <signal.h>
24 #include <zlib.h>
25 
26 #include "prop/minisat/utils/System.h"
27 #include "prop/minisat/utils/ParseUtils.h"
28 #include "prop/minisat/utils/Options.h"
29 #include "prop/minisat/core/Dimacs.h"
30 #include "prop/minisat/core/Solver.h"
31 
32 //=================================================================================================
33 
34 
35 namespace CVC4 {
36 namespace Minisat {
printStats(Solver & solver)37 void printStats(Solver& solver)
38 {
39     double cpu_time = cpuTime();
40     double mem_used = memUsedPeak();
41     printf("restarts              : %"PRIu64"\n", solver.starts);
42     printf("conflicts             : %-12"PRIu64"   (%.0f /sec)\n", solver.conflicts   , solver.conflicts   /cpu_time);
43     printf("decisions             : %-12"PRIu64"   (%4.2f %% random) (%.0f /sec)\n", solver.decisions, (float)solver.rnd_decisions*100 / (float)solver.decisions, solver.decisions   /cpu_time);
44     printf("propagations          : %-12"PRIu64"   (%.0f /sec)\n", solver.propagations, solver.propagations/cpu_time);
45     printf("conflict literals     : %-12"PRIu64"   (%4.2f %% deleted)\n", solver.tot_literals, (solver.max_literals - solver.tot_literals)*100 / (double)solver.max_literals);
46     if (mem_used != 0) printf("Memory used           : %.2f MB\n", mem_used);
47     printf("CPU time              : %g s\n", cpu_time);
48 }
49 
50 
51 static Solver* solver;
52 // Terminate by notifying the solver and back out gracefully. This is mainly to have a test-case
53 // for this feature of the Solver as it may take longer than an immediate call to '_exit()'.
SIGINT_interrupt(int signum)54 static void SIGINT_interrupt(int signum) { solver->interrupt(); }
55 
56 // Note that '_exit()' rather than 'exit()' has to be used. The reason is that 'exit()' calls
57 // destructors and may cause deadlocks if a malloc/free function happens to be running (these
58 // functions are guarded by locks for multithreaded use).
SIGINT_exit(int signum)59 static void SIGINT_exit(int signum) {
60     printf("\n"); printf("*** INTERRUPTED ***\n");
61     if (solver->verbosity > 0){
62         printStats(*solver);
63         printf("\n"); printf("*** INTERRUPTED ***\n"); }
64     _exit(1); }
65 
66 } /* CVC4::Minisat namespace */
67 } /* CVC4 namespace */
68 
69 
70 //=================================================================================================
71 // Main:
72 
73 
main(int argc,char ** argv)74 int main(int argc, char** argv)
75 {
76   using namespace CVC4;
77   using namespace CVC4::Minisat;
78     try {
79         setUsageHelp("USAGE: %s [options] <input-file> <result-output-file>\n\n  where input may be either in plain or gzipped DIMACS.\n");
80         // printf("This is MiniSat 2.0 beta\n");
81 
82 #if defined(__linux__)
83         fpu_control_t oldcw, newcw;
84         _FPU_GETCW(oldcw); newcw = (oldcw & ~_FPU_EXTENDED) | _FPU_DOUBLE; _FPU_SETCW(newcw);
85         printf("WARNING: for repeatability, setting FPU to use double precision\n");
86 #endif
87         // Extra options:
88         //
89         IntOption    verb   ("MAIN", "verb",   "Verbosity level (0=silent, 1=some, 2=more).", 1, IntRange(0, 2));
90         IntOption    cpu_lim("MAIN", "cpu-lim","Limit on CPU time allowed in seconds.\n", INT32_MAX, IntRange(0, INT32_MAX));
91         IntOption    mem_lim("MAIN", "mem-lim","Limit on memory usage in megabytes.\n", INT32_MAX, IntRange(0, INT32_MAX));
92 
93         parseOptions(argc, argv, true);
94 
95         Solver S;
96         double initial_time = cpuTime();
97 
98         S.verbosity = verb;
99 
100         solver = &S;
101         // Use signal handlers that forcibly quit until the solver will be able to respond to
102         // interrupts:
103         signal(SIGINT, SIGINT_exit);
104         signal(SIGXCPU,SIGINT_exit);
105 
106         // Set limit on CPU-time:
107         if (cpu_lim != INT32_MAX){
108             rlimit rl;
109             getrlimit(RLIMIT_CPU, &rl);
110             if (rl.rlim_max == RLIM_INFINITY || (rlim_t)cpu_lim < rl.rlim_max){
111                 rl.rlim_cur = cpu_lim;
112                 if (setrlimit(RLIMIT_CPU, &rl) == -1)
113                     printf("WARNING! Could not set resource limit: CPU-time.\n");
114             } }
115 
116         // Set limit on virtual memory:
117         if (mem_lim != INT32_MAX){
118             rlim_t new_mem_lim = (rlim_t)mem_lim * 1024*1024;
119             rlimit rl;
120             getrlimit(RLIMIT_AS, &rl);
121             if (rl.rlim_max == RLIM_INFINITY || new_mem_lim < rl.rlim_max){
122                 rl.rlim_cur = new_mem_lim;
123                 if (setrlimit(RLIMIT_AS, &rl) == -1)
124                     printf("WARNING! Could not set resource limit: Virtual memory.\n");
125             } }
126 
127         if (argc == 1)
128             printf("Reading from standard input... Use '--help' for help.\n");
129 
130         gzFile in = (argc == 1) ? gzdopen(0, "rb") : gzopen(argv[1], "rb");
131         if (in == NULL)
132             printf("ERROR! Could not open file: %s\n", argc == 1 ? "<stdin>" : argv[1]), exit(1);
133 
134         if (S.verbosity > 0){
135             printf("============================[ Problem Statistics ]=============================\n");
136             printf("|                                                                             |\n"); }
137 
138         parse_DIMACS(in, S);
139         gzclose(in);
140         FILE* res = (argc >= 3) ? fopen(argv[2], "wb") : NULL;
141 
142         if (S.verbosity > 0){
143             printf("|  Number of variables:  %12d                                         |\n", S.nVars());
144             printf("|  Number of clauses:    %12d                                         |\n", S.nClauses()); }
145 
146         double parsed_time = cpuTime();
147         if (S.verbosity > 0){
148             printf("|  Parse time:           %12.2f s                                       |\n", parsed_time - initial_time);
149             printf("|                                                                             |\n"); }
150 
151         // Change to signal-handlers that will only notify the solver and allow it to terminate
152         // voluntarily:
153         signal(SIGINT, SIGINT_interrupt);
154         signal(SIGXCPU,SIGINT_interrupt);
155 
156         if (!S.simplify()){
157             if (res != NULL) fprintf(res, "UNSAT\n"), fclose(res);
158             if (S.verbosity > 0){
159                 printf("===============================================================================\n");
160                 printf("Solved by unit propagation\n");
161                 printStats(S);
162                 printf("\n"); }
163             printf("UNSATISFIABLE\n");
164             exit(20);
165         }
166 
167         vec<Lit> dummy;
168         lbool ret = S.solveLimited(dummy);
169         if (S.verbosity > 0){
170             printStats(S);
171             printf("\n"); }
172         printf(ret == l_True ? "SATISFIABLE\n" : ret == l_False ? "UNSATISFIABLE\n" : "INDETERMINATE\n");
173         if (res != NULL){
174             if (ret == l_True){
175                 fprintf(res, "SAT\n");
176                 for (int i = 0; i < S.nVars(); i++)
177                     if (S.model[i] != l_Undef)
178                         fprintf(res, "%s%s%d", (i==0)?"":" ", (S.model[i]==l_True)?"":"-", i+1);
179                 fprintf(res, " 0\n");
180             }else if (ret == l_False)
181                 fprintf(res, "UNSAT\n");
182             else
183                 fprintf(res, "INDET\n");
184             fclose(res);
185         }
186 
187 #ifdef NDEBUG
188         exit(ret == l_True ? 10 : ret == l_False ? 20 : 0);     // (faster than "return", which will invoke the destructor for 'Solver')
189 #else
190         return (ret == l_True ? 10 : ret == l_False ? 20 : 0);
191 #endif
192     } catch (OutOfMemoryException&){
193         printf("===============================================================================\n");
194         printf("INDETERMINATE\n");
195         exit(0);
196     }
197 }
198