/*
 * Copyright 1998-2002 by Albert Cahalan; all rights resered.
 * This file may be used subject to the terms and conditions of the
 * GNU Library General Public License Version 2, or any later version
 * at your option, as published by the Free Software Foundation.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Library General Public License for more details.
 */
#include <sys/types.h>
#include <string.h>
#include "procps.h"
#include "escape.h"
#include "readproc.h"

// What it would be for a UTF-8 locale:
// "Z-------------------------------"
// "********************************"
// "********************************"
// "*******************************-"
// "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"  Trailing UTF-8, and badness in 8-bit.
// "yyyyyyyyyyyyyyyyyyyyyyyyyyyyyyyy"  Trailing UTF-8, and safe in 8-bit.
// "--222222222222222222222222222222"
// ".333333333333.3.44444444555566--"  The '.' means '3', with problem chars.
//
// Problems include non-shortest forms, UTF-16, and non-characters.
// The 4-byte, 5-byte, and 6-byte sequences are full of trouble too.

#if 0
/* sanitize a string, without the nice BSD library function:     */
/* strvis(vis_args, k->ki_args, VIS_TAB | VIS_NL | VIS_NOSLASH)  */
int octal_escape_str(char *restrict dst, const char *restrict src, size_t n)
{
	unsigned char c;
	char d;
	size_t i;
	const char codes[] = "Z------abtnvfr-------------e----" " *******************************"	/* better: do not print any space */
	    "****************************\\***"
	    "*******************************-"
	    "--------------------------------"
	    "********************************"
	    "********************************"
	    "********************************";
	for (i = 0; i < n;) {
		c = (unsigned char)*(src++);
		d = codes[c];
		switch (d) {
		case 'Z':
			goto leave;
		case '*':
			i++;
			*(dst++) = c;
			break;
		case '-':
			if (i + 4 > n)
				goto leave;
			i += 4;
			*(dst++) = '\\';
			*(dst++) = "01234567"[c >> 6];
			*(dst++) = "01234567"[(c >> 3) & 07];
			*(dst++) = "01234567"[c & 07];
			break;
		default:
			if (i + 2 > n)
				goto leave;
			i += 2;
			*(dst++) = '\\';
			*(dst++) = d;
			break;
		}
	}
leave:
	*(dst++) = '\0';
	return i;
}
#endif

/* sanitize a string via one-way mangle */
int escape_str(char *restrict dst, const char *restrict src, int bufsize,
	       int maxglyphs)
{
	unsigned char c;
	int my_glyphs = 0;
	int my_bytes = 0;
	const char codes[] =
	    "Z-------------------------------"
	    "********************************"
	    "********************************"
	    "*******************************-"
	    "--------------------------------"
	    "********************************"
	    "********************************"
	    "********************************";

	if (bufsize > maxglyphs + 1)
		bufsize = maxglyphs + 1;	// FIXME: assumes 8-bit locale

	for (;;) {
		if (my_glyphs >= maxglyphs)
			break;
		if (my_bytes + 1 >= bufsize)
			break;
		c = (unsigned char)*(src++);
		if (!c)
			break;
		if (codes[c] == '-')
			c = '?';
		my_glyphs++;
		my_bytes++;
		*(dst++) = c;
	}
	*(dst++) = '\0';
	return my_bytes;	// bytes of text, excluding the NUL
}

/////////////////////////////////////////////////

// escape an argv or environment string array
//
// bytes arg means sizeof(buf)
int escape_strlist(char *restrict dst, const char *restrict const *restrict src,
		   size_t bytes)
{
	size_t i = 0;

//if (!*src) {        just never call this function without checking first
//  do something nice
//}

	for (;;) {
		i += escape_str(dst + i, *src, bytes - i, bytes - i);	// FIXME: byte/glyph
		if (bytes - i < 3)
			break;	// need room for space, a character, and the NUL
		src++;
		if (!*src)
			break;	// need something to print
		dst[i++] = ' ';
	}
	return i;		// bytes of text, excluding the NUL
}

///////////////////////////////////////////////////

int escape_command(char *restrict const outbuf,
		   const proc_t * restrict const pp, int bytes, int glyphs,
		   unsigned flags)
{
	int overhead = 1;	// the trailing NUL
	int end = 0;

	if (bytes > glyphs + 1)
		bytes = glyphs + 1;	// FIXME: assumes 8-bit locale

	if (flags & ESC_ARGS) {
		const char **lc = (const char **)pp->cmdline;
		if (lc && *lc)
			return escape_strlist(outbuf, lc, bytes);
	}
	if (flags & ESC_BRACKETS) {
		overhead += 2;
	}
	if (flags & ESC_DEFUNCT) {
		if (pp->state == 'Z')
			overhead += 10;	// chars in " <defunct>"
		else
			flags &= ~ESC_DEFUNCT;
	}
	if (overhead >= bytes) {	// if no room for even one byte of the command name
		// you'd damn well better have _some_ space
		outbuf[0] = '-';
		outbuf[1] = '\0';
		return 1;
	}
	if (flags & ESC_BRACKETS) {
		outbuf[end++] = '[';
	}
	end +=
	    escape_str(outbuf + end, pp->cmd, bytes - overhead,
		       glyphs - overhead + 1);

	// Hmmm, do we want "[foo] <defunct>" or "[foo <defunct>]"?
	if (flags & ESC_BRACKETS) {
		outbuf[end++] = ']';
	}
	if (flags & ESC_DEFUNCT) {
		memcpy(outbuf + end, " <defunct>", 10);
		end += 10;
	}

	outbuf[end] = '\0';
	return end;		// bytes or glyphs, not including the NUL
}