broadcasting configuration

cellular_automaton/wireworld_c/configuration.c

@@ -92,7 +92,7 @@ void conf_init_from_args(conf_t *c, int argc, char* argv[])
    }
 
    if(optind > argc) {
-      fprintf(stderr, "Expected base name of input file (omitting '.wi' file extension)\n");
+      fprintf(stderr, "Expected base name of input file (omitting '%s' file extension)\n", FILE_EXT);
       MPI_Abort(MPI_COMM_WORLD, EXIT_FAILURE);
    }
 

cellular_automaton/wireworld_c/configuration.h

@@ -47,7 +47,7 @@ typedef struct
 #define CONF_T_N_INT_MEMBERS 6
 #define CONF_T_FIRST_INT_MEMBER verbosity_level
 
-#define CONF_T_N_LONG_MEMBERS 2
+#define CONF_T_N_LONG_MEMBERS 1
 #define CONF_T_FIRST_LONG_MEMBER n_generations_per_iteration
 
 #define CONF_T_N_CHAR_MEMBERS FILE_BASENAME_SZ

cellular_automaton/wireworld_c/main.c

@@ -9,7 +9,6 @@
 #include "world.h"
 #include "simulation.h"
 
-
 void broadcast_configuration(conf_t *c);
 
 void read_input(const conf_t *c, world_t *world);
@@ -20,11 +19,15 @@ void print_avg_timings(const conf_t *c, double total_time, double sim_time, doub
 
 int main(int argc, char* argv[])
 {
+   int rank, nprocs;
    conf_t config;
    world_t world;
 
    MPI_Init(&argc, &argv);
 
+   MPI_Comm_rank(MPI_COMM_WORLD, &rank);
+   MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
+
    // We want the program to stop on I/O errors
    // -> Change the default I/O error hander from MPI_ERRORS_RETURN to MPI_ERRORS_ARE_FATAL
    // Notes:
@@ -32,8 +35,12 @@ int main(int argc, char* argv[])
    //  * The default I/O error handler is associated to the null file handle, i.e. MPI_FILE_NULL.
    MPI_File_set_errhandler(MPI_FILE_NULL, MPI_ERRORS_ARE_FATAL);
 
-   // Parse command line arguments
-   conf_init_from_args(&config, argc, argv);
+   // Parse command line arguments and broadcast configuration
+   if(rank == 0) {
+      conf_init_from_args(&config, argc, argv);
+   }
+   broadcast_configuration(&config);
+
    if(info_enabled(&config)) conf_print(&config, stdout);
 
    // Read input file
@@ -48,6 +55,16 @@ int main(int argc, char* argv[])
    return EXIT_SUCCESS;
 }
 
+void broadcast_configuration(conf_t *c) {
+   MPI_Datatype conf_type;
+
+   mpitype_conf_init(&conf_type);
+
+   MPI_Bcast(c, 1, conf_type, 0, MPI_COMM_WORLD);
+
+   mpitype_conf_free(&conf_type);
+}
+
 void read_input(const conf_t *c, world_t *world) {
    int rank;
    const int periods[2] = {0}; // non-periodic boundaries