#include <sys/stat.h>		/* struct stat */
#include <stdlib.h>		/* malloc() */
#include <stdio.h>		/* fprintf() */
#include "stl.h"

/* load a STL file and return a pointer to the stl_t struct */
stl_t *	stl_load(const char * filename)
{
	struct stat s;
	if (stat(filename, &s))
	{
		fprintf(stderr, "Couldn't stat '%s'\n", filename);
		return NULL;
	}
	if (s.st_size < sizeof(stl_t))
	{
		fprintf(stderr, "Size of '%s' only %d bytes!\n", filename, s.st_size);
		return NULL;
	}
	FILE *fil;
	if ((fil = fopen(filename, "rb")) == NULL)
	{
		fprintf(stderr, "Couldn't open '%s'\n", filename);
		return NULL;
	}
	stl_t * stl = (stl_t *) malloc(s.st_size);
	fread(stl, 1, s.st_size, fil);
	fclose(fil);
	if (s.st_size <
		sizeof(stl_t) + sizeof(stl_face_t) * (stl_num_faces(stl)-1))
	{
		fprintf(stderr, "Size of '%s' only %d bytes, but has %d faces!\n",
			filename, s.st_size, stl_num_faces(stl));
		free(stl);
		return NULL;
	}
	return stl;
}