#include <stdio.h>
#include <time.h>
#include <procid.h>
#include <signal.h>
#include <errno.h>

#define PARTPD 724
#define FALSE (1==0)
#define TRUE !FALSE

extern char *getenv();
extern int os9fork();

static procid Child_process;

static char *Stars = "***********************************\n";
static char *Darrow= "VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV\n";
static char *Uarrow= "^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n";

void argwrong()
{
	puts("");
	puts("Usage: time [-r] <program_name> [arg1 arg2...argn]");
	puts("       -r will allow full redirection of output.");
	puts("       Normally, time outputs statistics on PORT (from environment).");
	puts("");
	exit(0);
}

main(argc, argv, envp)
int argc;
char *argv[], *envp[];
{
	int procn;
	int start, end;
	char *ioport;
	int fullredirect = FALSE;
	double totalticks;
	FILE *outpath;
	
    if ( argc == 1 )
        argwrong();
    if ( (argv[1][0] == '-') ) {
    	if( (argv[1][1] | 0x60) == 'r' ) {
    		fullredirect = TRUE;
    		argv++;
	    } else
	    	argwrong();
    }
    if ( ! fullredirect ) {
    	ioport = getenv("PORT");
    	if ( ioport == (char *)0x0 )
    		exit(_errmsg(1,"'PORT' environment variable not defined\n"));
    	if ( (outpath = fopen(ioport, "w")) == (FILE *)-1 )
    		outpath = stdout;
   	}
   	else
   		outpath = stdout;
   	fprintf(outpath, "\n%s\t\tProgram: %s\n%s", Stars, argv[1], Darrow);
   	fflush(outpath);
   	
    start = _getsys(D_Ticks, sizeof(int));

	if ( (procn = os9exec(os9fork, argv[1], &argv[1], envp, 0, 0)) == -1) {
		fprintf(outpath, "unable to fork %s!\n", argv[1]);
		exit(0);
	}
	do {
		tsleep(1);
		if (_get_process_desc(procn,PARTPD,&Child_process) == -1)
			_exit(_errmsg(errno, "Could not get process descriptor for %s!\n",
																argv[1]));
		end = _getsys(D_Ticks, sizeof(int));
	} while ( (Child_process._state & 0x100) == 0);
	
	while ( wait(0) != procn );
	
	fprintf(outpath, "%sProgram Statistics:\n CPU Ticks: ",Uarrow);
	fprintf(outpath, "user = %d system = %d\n", Child_process._uticks,
												Child_process._sticks);  
	totalticks = (double) (Child_process._uticks + Child_process._sticks);
	fprintf(outpath,"Total CPU Time (seconds): %lg\n", totalticks/(double)CLK_TCK);
	fprintf(outpath,"Clock Time (seconds): %lg\n", (double)(end-start)/(double)CLK_TCK);
	fprintf(outpath,"%% of time used by %s: %lg\n",argv[1], (totalticks/(double)(end-start))*100);
	fprintf(outpath,"F$ calls: %d     I$ calls: %d\n", Child_process._fcalls,
													   Child_process._icalls);
	fprintf(outpath,"Bytes written: %d     Bytes read: %d\n%s\n",
	                        Child_process._wbytes,Child_process._rbytes, Stars);
}