3 * @author Sam Moore (20503628) - 2012
4 * @purpose Contains main function, argument handling
5 * NOTE: This file is identical for both the single-threaded and multi-threaded versions of the program
12 #include <string.h> // For parsing arguments
17 // --- Variable definitions --- //
18 System universe; // global variable declared in "nbody.h" - The universe of bodies
19 Options options; // global variable declared in "nbody.h" - Options passed to program through arguments
22 // --- Function forward declarations --- //
23 void HandleArguments(int argc, char ** argv); //Interprets program arguments and sets up the "options" variable
24 unsigned UnsignedArgument(unsigned * i, int argc, char ** argv, unsigned * store, unsigned * store2); //Helper function to get switch value for unsigned
25 void FloatArgument(unsigned * i, int argc, char ** argv, float * store); //Helper function to get switch value for float
26 void DisplayStatistics(); //Called on exit of program, displays information about computation time, steps computed, etc
27 void Interrupt(int dummy); // Interrupt handler function, called when SIGINT (Ctrl-C) is sent to program
29 // --- Function implementations --- //
33 * @purpose The main function. Calls HandleArguments to set up options,
34 * sets up functions to call at exit, starts simulation and graphics loops
35 * @param argc - Number of arguments
36 * @param argv - The argument strings
38 int main(int argc, char** argv)
40 //Set default options values here
41 options.program = argv[0];
43 options.output = NULL;
44 options.num_threads = 0;
45 options.nested_threads = 0;
46 options.num_steps = 0;
48 options.draw_graphics = true;
49 options.pedantic_graphics = false;
50 options.print_positions = false;
51 options.verbosity = 0;
53 //If there are no arguments, print information about usage
56 printf("Usage: %s [OPTIONS] field\n", argv[0]);
57 printf("Controls:\n X - exit\n I, J, K, M - rotate\n W, Z, A, S - move to view"
58 " point\n ./, - zoom in/out\n +/- - scaled zoom in/out\n");
63 HandleArguments(argc, argv);
65 //Check there is an initial field.
66 if (options.input == NULL)
68 fprintf(stderr, "Usage: %s [OPTIONS] field\n", argv[0]);
69 fprintf(stderr, " (You did not provide a file for the initial field of bodies)\n");
73 signal(SIGINT, Interrupt); //Handle SIGINT signals
74 atexit(Universe_Cleanup); //On exit, cleanup universe (and write positions of bodies to file if supplied).
75 atexit(DisplayStatistics); //On exit, print information about the computations done
76 System_Init(&universe,options.input); //Initialise the universe from the initial field
78 //Setup the time of day at which the simulation starts
79 if (gettimeofday(&(options.start_time), NULL) != 0)
81 perror("Couldn't get time of day");
85 options.start_clock = clock(); //Get CPU cycles executed before simulation starts
86 Simulation_Run(argc, argv); // Start the simulation
88 //printf("Got here!\n");
89 exit(EXIT_FAILURE); //Should never get to this line
94 * @function HandleArguments
95 * @purpose Fill the "options" variable by parsing command line arguments
96 * @param argc - Number of arguments
97 * @param argv - Argument strings
99 void HandleArguments(int argc, char ** argv)
101 for (unsigned i = 1; i < argc; ++i) //For all arguments
103 if (argv[i][0] != '-') //If the argument is not a switch value...
105 //Interpret first non switch as input file, and second as output file.
106 //If there are too many non switch arguments, give an error.
107 if (options.input == NULL)
108 options.input = argv[i];
109 else if (options.output == NULL)
110 options.output = argv[i];
113 fprintf(stderr,"Usage: %s [OPTIONS] field [output]\n", argv[0]);
114 fprintf(stderr," (You provided too many file names)\n");
119 switch (argv[i][1]) //The argument is a switch if we get here
121 case 'n': //Number of threads switch
122 UnsignedArgument(&i, argc, argv, &(options.num_threads), &(options.nested_threads));
123 #ifdef SINGLE_THREADED
124 fprintf(stderr, "Warning: -%c switch has no effect in the single-threaded program.\n", argv[i][1]);
126 #endif //SINGLE_THREADED
128 case 's': //Number of steps switch
129 UnsignedArgument(&i, argc, argv, &(options.num_steps), NULL);
131 case 't': //Timeout switch (in seconds)
132 UnsignedArgument(&i, argc, argv, &(options.timeout), NULL);
134 case 'g': //Graphics switch
135 options.draw_graphics = !options.draw_graphics;
137 case 'v': //Verbosity switch
138 UnsignedArgument(&i, argc, argv, &(options.verbosity), NULL);
142 if (strcmp(argv[i]+1, "pedantic-graphics"))
144 options.pedantic_graphics = true;
145 #ifdef SINGLE_THREADED
146 fprintf(stderr, "Warning: %s switch has no effect in the single threaded program.\n", argv[i]);
147 #endif //SINGLE_THREADED
149 else if (strcmp(argv[i]+1, "fast-graphics"))
151 options.pedantic_graphics = false;
152 #ifdef SINGLE_THREADED
153 fprintf(stderr, "Warning: %s switch has no effect in the single threaded program.\n", argv[i]);
154 #endif //SINGLE_THREADED
159 fprintf(stderr, "Unrecognised switch -%s\n", argv[i]);
166 fprintf(stderr, "Unrecognised switch -%c\n", argv[i][1]);
175 * @function UnsignedArgument
176 * @purpose Helper function to get an unsigned integer following a argument switch
177 * @param i - position in the argument array, will be updated after this function
178 * @param argc - number of arguments
179 * @param argv - argument strings
180 * @param store - pointer to unsigned to store result in
181 * @param store2 - pointer to second unsigned
182 * @returns 1 if store was filled, 2 if both store1 and store2 were filled
184 unsigned UnsignedArgument(unsigned * i, int argc, char ** argv, unsigned * store, unsigned * store2)
188 fprintf(stderr,"Supply a positive integer for the -%c switch.\n", argv[*i][1]);
192 char * seperator = strstr(argv[*i+1], ":");
193 if (seperator != NULL)
197 fprintf(stderr,"Supply a positive integer for the -%c switch.\n", argv[*i][1]);
200 int val = atoi(seperator+1);
203 fprintf(stderr,"Supply a positive integer for the -%c switch.\n", argv[*i][1]);
206 *store2 = (unsigned)val;
211 int val = atoi(argv[*i+1]);
214 fprintf(stderr,"Supply a positive integer for the -%c switch. %s is invalid.\n", argv[*i][1], argv[*i+1]);
217 *store = (unsigned)val;
220 return (seperator == NULL) ? 1 : 2;
223 * @function FloatArgument
224 * @purpose Helper function to get a float following a argument switch
225 * @param i - position in the argument array, will be updated after this function
226 * @param argc - number of arguments
227 * @param argv - argument strings
228 * @param store - pointer to float to store result in
230 void FloatArgument(unsigned * i, int argc, char ** argv, float * store)
234 fprintf(stderr,"Supply a float for the -%c switch.\n", argv[*i][1]);
237 *store = atof(argv[*i+1]);
238 if (*store == 0.0 && argv[*i+1][0] != '0')
240 fprintf(stderr,"Supply a float for the -%c switch.\n", argv[*i][1]);
249 * @function Interrupt
250 * @purpose Handle SIGINT signal; quit the program gracefully, so that statistics are still displayed
251 * @param dummy - a dummy
254 void Interrupt(int dummy)