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#include "fractal-gen.h"
struct section_generator
{
char *executable_name;
void *(*generator)(void *);
};
int main(int argc, char **argv)
{
unsigned int size, iterat, cores, i, x, y;
double power;
char* bname;
data_section* sections;
void *(*generator)(void *);
struct section_generator generators[] = {
{ "mandelbrot-gen" , &generate_mandelbrot_section },
{ "burning-ship-gen" , &generate_burning_ship_section },
{ "tricorn-gen" , &generate_tricorn_section }
};
// Select correct generator for the fractal type
bname = basename(argv[0]);
generator = NULL;
for (i = 0; i < sizeof(generators)/sizeof(struct section_generator); i++)
if (strcmp(bname, generators[i].executable_name) == 0)
generator = generators[i].generator;
if (generator == NULL)
{
fprintf(stderr, "Don't call this directly, call a symlink to me\n");
return EXIT_FAILURE;
}
if (argc != 4 && argc != 5)
{
fprintf(stderr, "%s size iterat power [threads]\n", argv[0]);
return EXIT_FAILURE;
}
size = atoi(argv[1]);
iterat = atoi(argv[2]);
power = atof(argv[3]);
// Fetch number of cores available on machine
cores = argc == 5? atoi(argv[4]) : sysconf(_SC_NPROCESSORS_ONLN); // Screw maintainability ;)
// Interlacing is column-based, can't have more workers than columns
if (cores > size)
{
fprintf(stderr, "WARN: Capping number of threads to image width\n");
cores = size;
}
assert(size > 0);
assert(iterat > 0);
assert(cores > 0);
// Allocate memory for sections
if ((sections = malloc(sizeof(data_section)*cores)) == NULL)
{
perror("malloc");
return EXIT_FAILURE;
}
// Spawn all the threads! Something something interlacing
fprintf(stderr, "Spawning %d threads:\n", cores);
for (i = 0; i < cores; i++)
{
// Has to be a better way
sections[i].core = i;
sections[i].cores = cores;
sections[i].size = size;
sections[i].power = power;
sections[i].iterat = iterat;
// A bit complex, icky, will document later
if (i < (size%cores))
x = (size*((int)(size/cores)+1));
else
x = (size*(int)(size/cores));
if ((sections[i].data = malloc(x)) == NULL)
{
fprintf(stderr, "\n");
perror("malloc");
// Free already allocated chunks of memory
i--;
while(i-- + 1)
free(sections[i].data);
free(sections);
return EXIT_FAILURE;
}
fprintf(stderr, " -> Thread #%d (%d bytes data area)\r", i+1, x);
pthread_create(§ions[i].thread, NULL, generator, &(sections[i]));
}
// Wait for each thread to complete
for (i = 0; i < cores; i++)
pthread_join(sections[i].thread, NULL);
// Output PGM Header
printf("P5\n%d\n%d\n255\n",size,size);
// Vomit the data segments back onto the screen, deinterlacing
// TO DO: look at fwrite performance benefits over putchar
for (y = 0; y < size; y++)
for (x = 0; x < size; x++)
putchar(sections[y%cores].data[(y/cores)*size + x]);
fprintf(stderr, "\nDone\n");
// Free the memory we allocated for point data
for (i = 0; i < cores; i++)
free(sections[i].data);
free(sections);
return 0;
}
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