/*
 * err.c — diagnostics.
 *
 * fatal	prints, sets exit(1).
 * errorf	prints with source location, increments nerrors.
 * warnf	prints with source location, increments nwarnings.
 *
 * Plan 9 style: short, no levels beyond fatal/error/warn, no colour.
 */
#include "ww.h"
#include <stdlib.h>
#include <string.h>

Pos	noPos = { "<none>", 0, 0 };
int	nerrors;
int	nwarnings;
FILE	*errout;	/* set by main; defaults to stderr */

static FILE *
out(void)
{
	return errout ? errout : stderr;
}

static void
prefix(Pos p)
{
	FILE *f = out();
	if (p.file == NULL)
		p = noPos;
	if (p.line > 0)
		fprintf(f, "%s:%d:%d: ", p.file, p.line, p.col);
	else
		fprintf(f, "%s: ", p.file);
}

void
fatal(const char *fmt, ...)
{
	FILE *f = out();
	va_list ap;
	fprintf(f, "ww: ");
	va_start(ap, fmt);
	vfprintf(f, fmt, ap);
	va_end(ap);
	fprintf(f, "\n");
	exit(1);
}

void
errorf(Pos p, const char *fmt, ...)
{
	FILE *f = out();
	va_list ap;
	prefix(p);
	fprintf(f, "error: ");
	va_start(ap, fmt);
	vfprintf(f, fmt, ap);
	va_end(ap);
	fprintf(f, "\n");
	nerrors++;
}

void
warnf(Pos p, const char *fmt, ...)
{
	FILE *f = out();
	va_list ap;
	prefix(p);
	fprintf(f, "warning: ");
	va_start(ap, fmt);
	vfprintf(f, fmt, ap);
	va_end(ap);
	fprintf(f, "\n");
	nwarnings++;
}