/******************************************************************************
* debug.c
*		Debugging functions.
*
* Copyright (c)1994-95 David R. Tribble, all rights reserved.
*
* 1.00 09-17-1994 drt.	First cut.
* 1.01 09-24-1994 drt.	Split .c off from .cpp source.
* 1.02 04-20-1995 drt.	Added dbg_hexdump().
*/


/* Identification */

static const char	id[] =	"@(#)1.02 04-20-1995 " __FILE__ ;


/* Includes */

#include <ctype.h>
#include <stdarg.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "debug.h"


/* Private variables */

const char *	dbg_fname =	NULL;


/* Public variables */

FILE *		dbg_f = 	NULL;
int			dbg_flags =	0x0000;


/******************************************************************************
* dbg_open
*		Open file name `fname' with mode `mode' as the debugging output.
*
* Returns
*		File pointer if successful, or NULL if not.
*/

FILE * dbg_open(const char *fname, const char *mode)
{
	/* Check args */
	if (fname == NULL)
		return NULL;

	if (mode == NULL)
		mode = "w";

	/* Save off file name */
	if (dbg_fname != NULL)
		free((char *)dbg_fname);

	dbg_fname = strdup(fname);

	/* Open debugging output file */
	dbg_f = fopen(fname, mode);

	return dbg_f;
}


/******************************************************************************
* dbg_close
*		Close the debugging output file.
*
* Returns
*		Zero if successful, or -1 if not.
*/

int dbg_close(void)
{
	int		rc;

	/* Check that debugging output file is open */
	if (dbg_f == NULL)
		return 0;

	/* Close debugging output file */
	fflush(dbg_f);
	rc = fclose(dbg_f);
	if (rc != -1)
		dbg_f = NULL;

	return rc;
}


/******************************************************************************
* dbgf
*		Print formatted args to debugging output.
*
* Returns
*		Same value that vfprintf() returns.
*/

int dbgf(const char *fmt, ...)
{
	va_list		ap;
	int			rc;

	/* Check for debugging output enabled */
	if (dbg_f == NULL)
		return 0;

	/* Handle flags */
	if (dbg_flags & DBG_REOPEN  &&  dbg_fname != NULL)
	{
		/* Close debug output file */
		fflush(dbg_f);
		fclose(dbg_f);
		dbg_f = NULL;

		/* Reopen debug output file */
		dbg_f = fopen(dbg_fname, "a");
		if (dbg_f == NULL)
			return -1;
	}

	/* Print formatted args */
	va_start(ap, fmt);
	rc = vfprintf(dbg_f, fmt, ap);
	fflush(dbg_f);

	return rc;
}


/******************************************************************************
* dbg_hexdump
*		Dump contents of memory area `dat' of `len' bytes in hex and character
*		form to stream `dbg_fp'.
*
* Returns
*		`len'.
*/

int dbg_hexdump(const void *dat, unsigned len)
{
	const unsigned char *	d;
	int		err;
	int		inc;
	int		i, j;

	/* Check args */
	if (dbg_f == NULL)
		return -1;
	if (dat == NULL)
		return -1;
	if (len == 0)
		return 0;

	/* Dump data area */
	err = errno;
	d = (const unsigned char *) dat;

	inc = (len <= 8) ? 0x08 : 0x10;

	for (i = 0;  i < len;  i += inc)
	{
		dbgf(" %04X ", i);

		for (j = 0;  j < inc  &&  i+j < len;  j++)
			dbgf(" %.2X", d[i+j]);

		for (;  j < inc;  j++)
			dbgf(" ..");

		dbgf("  ");

		for (j = 0;  j < inc  &&  i+j < len;  j++)
			dbgf("%c", isprint(d[i+j]) ? d[i+j] : '.');

		dbgf("\n");
	}

	errno = err;
	return len;
}


/* End debug.c */