#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdarg.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#include <errno.h>
#include "util.h"
extern const char *progname;

void die(const char *fmt, ...)
{
        va_list ap;
        va_start(ap, fmt);
        fprintf(stderr, "%s: ", progname);
        vfprintf(stderr, fmt, ap);
        va_end(ap);
        exit(1);
}

void warn(const char *fmt, ...)
{
        va_list ap;
        va_start(ap, fmt);
        fprintf(stderr, "%s: ", progname);
        vfprintf(stderr, fmt, ap);
        va_end(ap);
}

void setprogname(const char *name)
{
        const char *slash=strrchr(name, '/');
        progname=slash? slash+1 : name;
}

void usage(FILE *stream, int status)
{
	fprintf(stream, "Usage: %s pid fd filename\n", progname);
	if (ferror(stream) || fclose(stream)) status=1;
	exit(status);
}

pid_t str_to_pid_or_pgrp(const char *s)
{
	char *endptr;
	long value;
	pid_t pid;

	errno=0;
	value=strtol(s, &endptr, 10);
	if (!*s || *endptr) die("Invalid pid: %s\n", s);
	if ((value==LONG_MIN || value==LONG_MAX) && errno==ERANGE) 
		die("pid out of range for long: %s\n", s);
	pid=value;
	if (pid!=value) die("pid out of range: %s\n", s);
	return pid;
}

pid_t str_to_pid(const char *s)
{
	pid_t pid;
	pid=str_to_pid_or_pgrp(s);
	if (pid<=0) die("Invalid pid: %s\n", s);
	return pid;
}

int str_to_fd(const char *s)
{
	char *endptr;
	long value;
	int fd;

	errno=0;
	value=strtol(s, &endptr, 10);
	if (!*s || *endptr) die("Invalid fd: %s\n");
	if ((value==LONG_MIN || value==LONG_MAX) && errno==ERANGE) 
		die("fd out of range for long: %s\n", s);
	if (value<0) die("Invalid fd: %s\n", s);
	fd=value;
	if (fd!=value) die("fd out of range: %s\n", s);
	return fd;
}