optfunc.c

/*
 * Copyright (C) 1984-2023  Mark Nudelman
 *
 * You may distribute under the terms of either the GNU General Public
 * License or the Less License, as specified in the README file.
 *
 * For more information, see the README file.
 */


/*
 * Handling functions for command line options.
 *
 * Most options are handled by the generic code in option.c.
 * But all string options, and a few non-string options, require
 * special handling specific to the particular option.
 * This special processing is done by the "handling functions" in this file.
 *
 * Each handling function is passed a "type" and, if it is a string
 * option, the string which should be "assigned" to the option.
 * The type may be one of:
 *      INIT    The option is being initialized from the command line.
 *      TOGGLE  The option is being changed from within the program.
 *      QUERY   The setting of the option is merely being queried.
 */

#include "less.h"
#include "option.h"

extern int nbufs;
extern int bufspace;
extern int pr_type;
extern int plusoption;
extern int swindow;
extern int sc_width;
extern int sc_height;
extern int secure;
extern int dohelp;
extern int is_tty;
extern char openquote;
extern char closequote;
extern char *prproto[];
extern char *eqproto;
extern char *hproto;
extern char *wproto;
extern char *every_first_cmd;
extern IFILE curr_ifile;
extern char version[];
extern int jump_sline;
extern long jump_sline_fraction;
extern int shift_count;
extern long shift_count_fraction;
extern char rscroll_char;
extern int rscroll_attr;
extern int mousecap;
extern int wheel_lines;
extern int less_is_more;
extern int linenum_width;
extern int status_col_width;
extern int use_color;
extern int want_filesize;
extern int header_lines;
extern int header_cols;
extern int def_search_type;
extern int chopline;
extern int tabstops[];
extern int ntabstops;
extern int tabdefault;
#if LOGFILE
extern char *namelogfile;
extern int force_logfile;
extern int logfile;
#endif
#if TAGS
public char *tagoption = NULL;
extern char *tags;
extern char ztags[];
#endif
#if LESSTEST
extern char *ttyin_name;
#endif /*LESSTEST*/
#if MSDOS_COMPILER
extern int nm_fg_color, nm_bg_color;
extern int bo_fg_color, bo_bg_color;
extern int ul_fg_color, ul_bg_color;
extern int so_fg_color, so_bg_color;
extern int bl_fg_color, bl_bg_color;
extern int sgr_mode;
#if MSDOS_COMPILER==WIN32C
#ifndef COMMON_LVB_UNDERSCORE
#define COMMON_LVB_UNDERSCORE 0x8000
#endif
#endif
#endif


#if LOGFILE
/*
 * Handler for -o option.
 */
public void opt_o(int type, char *s)
{
	PARG parg;
	char *filename;

	if (secure)
	{
		error("log file support is not available", NULL_PARG);
		return;
	}
	switch (type)
	{
	case INIT:
		namelogfile = save(s);
		break;
	case TOGGLE:
		if (ch_getflags() & CH_CANSEEK)
		{
			error("Input is not a pipe", NULL_PARG);
			return;
		}
		if (logfile >= 0)
		{
			error("Log file is already in use", NULL_PARG);
			return;
		}
		s = skipsp(s);
		if (namelogfile != NULL)
			free(namelogfile);
		filename = lglob(s);
		namelogfile = shell_unquote(filename);
		free(filename);
		use_logfile(namelogfile);
		sync_logfile();
		break;
	case QUERY:
		if (logfile < 0)
			error("No log file", NULL_PARG);
		else
		{
			parg.p_string = namelogfile;
			error("Log file \"%s\"", &parg);
		}
		break;
	}
}

/*
 * Handler for -O option.
 */
public void opt__O(int type, char *s)
{
	force_logfile = TRUE;
	opt_o(type, s);
}
#endif

/*
 * Handlers for -j option.
 */
public void opt_j(int type, char *s)
{
	PARG parg;
	int len;
	int err;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		if (*s == '.')
		{
			s++;
			jump_sline_fraction = getfraction(&s, "j", &err);
			if (err)
				error("Invalid line fraction", NULL_PARG);
			else
				calc_jump_sline();
		} else
		{
			int sline = getnum(&s, "j", &err);
			if (err)
				error("Invalid line number", NULL_PARG);
			else
			{
				jump_sline = sline;
				jump_sline_fraction = -1;
			}
		}
		break;
	case QUERY:
		if (jump_sline_fraction < 0)
		{
			parg.p_int =  jump_sline;
			error("Position target at screen line %d", &parg);
		} else
		{
			char buf[24];
			SNPRINTF1(buf, sizeof(buf), ".%06ld", jump_sline_fraction);
			len = (int) strlen(buf);
			while (len > 2 && buf[len-1] == '0')
				len--;
			buf[len] = '\0';
			parg.p_string = buf;
			error("Position target at screen position %s", &parg);
		}
		break;
	}
}

public void calc_jump_sline(void)
{
	if (jump_sline_fraction < 0)
		return;
	jump_sline = sc_height * jump_sline_fraction / NUM_FRAC_DENOM;
}

/*
 * Handlers for -# option.
 */
public void opt_shift(int type, char *s)
{
	PARG parg;
	int len;
	int err;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		if (*s == '.')
		{
			s++;
			shift_count_fraction = getfraction(&s, "#", &err);
			if (err)
				error("Invalid column fraction", NULL_PARG);
			else
				calc_shift_count();
		} else
		{
			int hs = getnum(&s, "#", &err);
			if (err)
				error("Invalid column number", NULL_PARG);
			else
			{
				shift_count = hs;
				shift_count_fraction = -1;
			}
		}
		break;
	case QUERY:
		if (shift_count_fraction < 0)
		{
			parg.p_int = shift_count;
			error("Horizontal shift %d columns", &parg);
		} else
		{
			char buf[24];
			SNPRINTF1(buf, sizeof(buf), ".%06ld", shift_count_fraction);
			len = (int) strlen(buf);
			while (len > 2 && buf[len-1] == '0')
				len--;
			buf[len] = '\0';
			parg.p_string = buf;
			error("Horizontal shift %s of screen width", &parg);
		}
		break;
	}
}

public void calc_shift_count(void)
{
	if (shift_count_fraction < 0)
		return;
	shift_count = sc_width * shift_count_fraction / NUM_FRAC_DENOM;
}

#if USERFILE
public void opt_k(int type, char *s)
{
	PARG parg;

	switch (type)
	{
	case INIT:
		if (lesskey(s, 0))
		{
			parg.p_string = s;
			error("Cannot use lesskey file \"%s\"", &parg);
		}
		break;
	}
}

#if HAVE_LESSKEYSRC 
public void opt_ks(int type, char *s)
{
	PARG parg;

	switch (type)
	{
	case INIT:
		if (lesskey_src(s, 0))
		{
			parg.p_string = s;
			error("Cannot use lesskey source file \"%s\"", &parg);
		}
		break;
	}
}
#endif /* HAVE_LESSKEYSRC */
#endif /* USERFILE */

#if TAGS
/*
 * Handler for -t option.
 */
public void opt_t(int type, char *s)
{
	IFILE save_ifile;
	POSITION pos;

	switch (type)
	{
	case INIT:
		tagoption = save(s);
		/* Do the rest in main() */
		break;
	case TOGGLE:
		if (secure)
		{
			error("tags support is not available", NULL_PARG);
			break;
		}
		findtag(skipsp(s));
		save_ifile = save_curr_ifile();
		/*
		 * Try to open the file containing the tag
		 * and search for the tag in that file.
		 */
		if (edit_tagfile() || (pos = tagsearch()) == NULL_POSITION)
		{
			/* Failed: reopen the old file. */
			reedit_ifile(save_ifile);
			break;
		}
		unsave_ifile(save_ifile);
		jump_loc(pos, jump_sline);
		break;
	}
}

/*
 * Handler for -T option.
 */
public void opt__T(int type, char *s)
{
	PARG parg;
	char *filename;

	switch (type)
	{
	case INIT:
		tags = save(s);
		break;
	case TOGGLE:
		s = skipsp(s);
		if (tags != NULL && tags != ztags)
			free(tags);
		filename = lglob(s);
		tags = shell_unquote(filename);
		free(filename);
		break;
	case QUERY:
		parg.p_string = tags;
		error("Tags file \"%s\"", &parg);
		break;
	}
}
#endif

/*
 * Handler for -p option.
 */
public void opt_p(int type, char *s)
{
	switch (type)
	{
	case INIT:
		/*
		 * Unget a command for the specified string.
		 */
		if (less_is_more)
		{
			/*
			 * In "more" mode, the -p argument is a command,
			 * not a search string, so we don't need a slash.
			 */
			every_first_cmd = save(s);
		} else
		{
			plusoption = TRUE;
			 /*
			  * {{ This won't work if the "/" command is
			  *    changed or invalidated by a .lesskey file. }}
			  */
			ungetsc("/");
			ungetsc(s);
			ungetcc_back(CHAR_END_COMMAND);
		}
		break;
	}
}

/*
 * Handler for -P option.
 */
public void opt__P(int type, char *s)
{
	char **proto;
	PARG parg;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		/*
		 * Figure out which prototype string should be changed.
		 */
		switch (*s)
		{
		case 's':  proto = &prproto[PR_SHORT];  s++;    break;
		case 'm':  proto = &prproto[PR_MEDIUM]; s++;    break;
		case 'M':  proto = &prproto[PR_LONG];   s++;    break;
		case '=':  proto = &eqproto;            s++;    break;
		case 'h':  proto = &hproto;             s++;    break;
		case 'w':  proto = &wproto;             s++;    break;
		default:   proto = &prproto[PR_SHORT];          break;
		}
		free(*proto);
		*proto = save(s);
		break;
	case QUERY:
		parg.p_string = prproto[pr_type];
		error("%s", &parg);
		break;
	}
}

/*
 * Handler for the -b option.
 */
	/*ARGSUSED*/
public void opt_b(int type, char *s)
{
	switch (type)
	{
	case INIT:
	case TOGGLE:
		/*
		 * Set the new number of buffers.
		 */
		ch_setbufspace(bufspace);
		break;
	case QUERY:
		break;
	}
}

/*
 * Handler for the -i option.
 */
	/*ARGSUSED*/
public void opt_i(int type, char *s)
{
	switch (type)
	{
	case TOGGLE:
		chg_caseless();
		break;
	case QUERY:
	case INIT:
		break;
	}
}

/*
 * Handler for the -V option.
 */
	/*ARGSUSED*/
public void opt__V(int type, char *s)
{
	switch (type)
	{
	case TOGGLE:
	case QUERY:
		dispversion();
		break;
	case INIT:
		set_output(1); /* Force output to stdout per GNU standard for --version output. */
		putstr("less ");
		putstr(version);
		putstr(" (");
		putstr(pattern_lib_name());
		putstr(" regular expressions)\n");
		{
			char constant *copyright = 
				"Copyright (C) 1984-2023  Mark Nudelman\n\n";
			putstr(copyright);
		}
		if (version[strlen(version)-1] == 'x')
		{
			putstr("** This is an EXPERIMENTAL build of the 'less' software,\n");
			putstr("** and may not function correctly.\n");
			putstr("** Obtain release builds from the web page below.\n\n");
		}
#if LESSTEST
		putstr("This build supports LESSTEST.\n");
#endif /*LESSTEST*/
		putstr("less comes with NO WARRANTY, to the extent permitted by law.\n");
		putstr("For information about the terms of redistribution,\n");
		putstr("see the file named README in the less distribution.\n");
		putstr("Home page: https://greenwoodsoftware.com/less\n");
		quit(QUIT_OK);
		break;
	}
}

#if MSDOS_COMPILER
/*
 * Parse an MSDOS color descriptor.
 */
static void colordesc(char *s, int *fg_color, int *bg_color)
{
	int fg, bg;
#if MSDOS_COMPILER==WIN32C
	int ul = 0;
 
	if (*s == 'u')
	{
		ul = COMMON_LVB_UNDERSCORE;
		s++;
		if (*s == '\0')
		{
			*fg_color = nm_fg_color | ul;
			*bg_color = nm_bg_color;
			return;
		}
	}
#endif
	if (parse_color(s, &fg, &bg) == CT_NULL)
	{
		PARG p;
		p.p_string = s;
		error("Invalid color string \"%s\"", &p);
	} else
	{
		if (fg == CV_NOCHANGE)
			fg = nm_fg_color;
		if (bg == CV_NOCHANGE)
			bg = nm_bg_color;
#if MSDOS_COMPILER==WIN32C
		fg |= ul;
#endif
		*fg_color = fg;
		*bg_color = bg;
	}
}
#endif

static int color_from_namechar(char namechar)
{
	switch (namechar)
	{
	case 'B': return AT_COLOR_BIN;
	case 'C': return AT_COLOR_CTRL;
	case 'E': return AT_COLOR_ERROR;
	case 'H': return AT_COLOR_HEADER;
	case 'M': return AT_COLOR_MARK;
	case 'N': return AT_COLOR_LINENUM;
	case 'P': return AT_COLOR_PROMPT;
	case 'R': return AT_COLOR_RSCROLL;
	case 'S': return AT_COLOR_SEARCH;
	case 'W': case 'A': return AT_COLOR_ATTN;
	case 'n': return AT_NORMAL;
	case 's': return AT_STANDOUT;
	case 'd': return AT_BOLD;
	case 'u': return AT_UNDERLINE;
	case 'k': return AT_BLINK;
	default:  return -1;
	}
}

/*
 * Handler for the -D option.
 */
	/*ARGSUSED*/
public void opt_D(int type, char *s)
{
	PARG p;
	int attr;

	switch (type)
	{
	case INIT:
	case TOGGLE:
#if MSDOS_COMPILER
		if (*s == 'a')
		{
			sgr_mode = !sgr_mode;
			break;
		}
#endif
		attr = color_from_namechar(s[0]);
		if (attr < 0)
		{
			p.p_char = s[0];
			error("Invalid color specifier '%c'", &p);
			return;
		}
		if (!use_color && (attr & AT_COLOR))
		{
			error("Set --use-color before changing colors", NULL_PARG);
			return;
		}
		s++;
#if MSDOS_COMPILER
		if (!(attr & AT_COLOR))
		{
			switch (attr)
			{
			case AT_NORMAL:
				colordesc(s, &nm_fg_color, &nm_bg_color);
				break;
			case AT_BOLD:
				colordesc(s, &bo_fg_color, &bo_bg_color);
				break;
			case AT_UNDERLINE:
				colordesc(s, &ul_fg_color, &ul_bg_color);
				break;
			case AT_BLINK:
				colordesc(s, &bl_fg_color, &bl_bg_color);
				break;
			case AT_STANDOUT:
				colordesc(s, &so_fg_color, &so_bg_color);
				break;
			}
			if (type == TOGGLE)
			{
				at_enter(AT_STANDOUT);
				at_exit();
			}
		} else
#endif
		if (set_color_map(attr, s) < 0)
		{
			p.p_string = s;
			error("Invalid color string \"%s\"", &p);
			return;
		}
		break;
#if MSDOS_COMPILER
	case QUERY:
		p.p_string = (sgr_mode) ? "on" : "off";
		error("SGR mode is %s", &p);
		break;
#endif
	}
}

/*
 */
public void set_tabs(char *s, int len)
{
	int i = 0;
	char *es = s + len;
	/* Start at 1 because tabstops[0] is always zero. */
	for (i = 1;  i < TABSTOP_MAX;  )
	{
		int n = 0;
		while (s < es && *s >= '0' && *s <= '9')
			n = (10 * n) + (*s++ - '0');
		if (n > tabstops[i-1])
			tabstops[i++] = n;
		while (s < es && *s == ' ')
			s++;
		if (s == es || *s++ != ',')
			break;
	}
	if (i < 2)
		return;
	ntabstops = i;
	tabdefault = tabstops[ntabstops-1] - tabstops[ntabstops-2];
}

/*
 * Handler for the -x option.
 */
public void opt_x(int type, char *s)
{
	char msg[60+((INT_STRLEN_BOUND(int)+1)*TABSTOP_MAX)];
	int i;
	PARG p;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		set_tabs(s, strlen(s));
		break;
	case QUERY:
		strcpy(msg, "Tab stops ");
		if (ntabstops > 2)
		{
			for (i = 1;  i < ntabstops;  i++)
			{
				if (i > 1)
					strcat(msg, ",");
				sprintf(msg+strlen(msg), "%d", tabstops[i]);
			}
			sprintf(msg+strlen(msg), " and then ");
		}
		sprintf(msg+strlen(msg), "every %d spaces",
			tabdefault);
		p.p_string = msg;
		error("%s", &p);
		break;
	}
}


/*
 * Handler for the -" option.
 */
public void opt_quote(int type, char *s)
{
	char buf[3];
	PARG parg;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		if (s[0] == '\0')
		{
			openquote = closequote = '\0';
			break;
		}
		if (s[1] != '\0' && s[2] != '\0')
		{
			error("-\" must be followed by 1 or 2 chars", NULL_PARG);
			return;
		}
		openquote = s[0];
		if (s[1] == '\0')
			closequote = openquote;
		else
			closequote = s[1];
		break;
	case QUERY:
		buf[0] = openquote;
		buf[1] = closequote;
		buf[2] = '\0';
		parg.p_string = buf;
		error("quotes %s", &parg);
		break;
	}
}

/*
 * Handler for the --rscroll option.
 */
	/*ARGSUSED*/
public void opt_rscroll(int type, char *s)
{
	PARG p;

	switch (type)
	{
	case INIT:
	case TOGGLE: {
		char *fmt;
		int attr = AT_STANDOUT;
		setfmt(s, &fmt, &attr, "*s>");
		if (strcmp(fmt, "-") == 0)
		{
			rscroll_char = 0;
		} else
		{
			rscroll_char = *fmt ? *fmt : '>';
			rscroll_attr = attr|AT_COLOR_RSCROLL;
		}
		break; }
	case QUERY: {
		p.p_string = rscroll_char ? prchar(rscroll_char) : "-";
		error("rscroll char is %s", &p);
		break; }
	}
}

/*
 * "-?" means display a help message.
 * If from the command line, exit immediately.
 */
	/*ARGSUSED*/
public void opt_query(int type, char *s)
{
	switch (type)
	{
	case QUERY:
	case TOGGLE:
		error("Use \"h\" for help", NULL_PARG);
		break;
	case INIT:
		dohelp = 1;
	}
}

/*
 * Handler for the --mouse option.
 */
	/*ARGSUSED*/
public void opt_mousecap(int type, char *s)
{
	switch (type)
	{
	case TOGGLE:
		if (mousecap == OPT_OFF)
			deinit_mouse();
		else
			init_mouse();
		break;
	case INIT:
	case QUERY:
		break;
	}
}

/*
 * Handler for the --wheel-lines option.
 */
	/*ARGSUSED*/
public void opt_wheel_lines(int type, char *s)
{
	switch (type)
	{
	case INIT:
	case TOGGLE:
		if (wheel_lines <= 0)
			wheel_lines = default_wheel_lines();
		break;
	case QUERY:
		break;
	}
}

/*
 * Handler for the --line-number-width option.
 */
	/*ARGSUSED*/
public void opt_linenum_width(int type, char *s)
{
	PARG parg;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		if (linenum_width > MAX_LINENUM_WIDTH)
		{
			parg.p_int = MAX_LINENUM_WIDTH;
			error("Line number width must not be larger than %d", &parg);
			linenum_width = MIN_LINENUM_WIDTH;
		} 
		break;
	case QUERY:
		break;
	}
}

/*
 * Handler for the --status-column-width option.
 */
	/*ARGSUSED*/
public void opt_status_col_width(int type, char *s)
{
	PARG parg;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		if (status_col_width > MAX_STATUSCOL_WIDTH)
		{
			parg.p_int = MAX_STATUSCOL_WIDTH;
			error("Status column width must not be larger than %d", &parg);
			status_col_width = 2;
		}
		break;
	case QUERY:
		break;
	}
}

/*
 * Handler for the --file-size option.
 */
	/*ARGSUSED*/
public void opt_filesize(int type, char *s)
{
	switch (type)
	{
	case INIT:
	case TOGGLE:
		if (want_filesize && curr_ifile != NULL && ch_length() == NULL_POSITION)
			scan_eof();
		break;
	case QUERY:
		break;
	}
}

/*
 * Handler for the --header option.
 */
	/*ARGSUSED*/
public void opt_header(int type, char *s)
{
	int err;
	int n;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		header_lines = 0;
		header_cols = 0;
		if (*s != ',')
		{
			n = getnum(&s, "header", &err);
			if (err)
			{
				error("invalid number of lines", NULL_PARG);
				return;
			}
			header_lines = n;
		}
		if (*s == ',')
		{
			++s;
			n = getnum(&s, "header", &err);
			if (err)
				error("invalid number of columns", NULL_PARG);
			else
				header_cols = n;
		}
		break;
	case QUERY:
		{
			char buf[2*INT_STRLEN_BOUND(int)+2];
			PARG parg;
			SNPRINTF2(buf, sizeof(buf), "%d,%d", header_lines, header_cols);
			parg.p_string = buf;
			error("header (lines,columns) is %s", &parg);
		}
		break;
	}
}

/*
 * Handler for the --search-options option.
 */
	/*ARGSUSED*/
public void opt_search_type(int type, char *s)
{
	int st;
	PARG parg;
	char buf[16];
	char *bp;

	switch (type)
	{
	case INIT:
	case TOGGLE:
		st = 0;
		for (;  *s != '\0';  s++)
		{
			switch (*s)
			{
			case 'E': case 'e': case CONTROL('E'): st |= SRCH_PAST_EOF;   break;
			case 'F': case 'f': case CONTROL('F'): st |= SRCH_FIRST_FILE; break;
			case 'K': case 'k': case CONTROL('K'): st |= SRCH_NO_MOVE;    break;
			case 'N': case 'n': case CONTROL('N'): st |= SRCH_NO_MATCH;   break;
			case 'R': case 'r': case CONTROL('R'): st |= SRCH_NO_REGEX;   break;
			case 'W': case 'w': case CONTROL('W'): st |= SRCH_WRAP;       break;
			case '-': st = 0; break;
			case '^': break;
			default:
				parg.p_char = *s;
				error("invalid search option '%c'", &parg);
				return;
			}
		}
		def_search_type = norm_search_type(st);
		break;
	case QUERY:
		bp = buf;
		if (def_search_type & SRCH_PAST_EOF)   *bp++ = 'E'; 
		if (def_search_type & SRCH_FIRST_FILE) *bp++ = 'F'; 
		if (def_search_type & SRCH_NO_MOVE)    *bp++ = 'K'; 
		if (def_search_type & SRCH_NO_MATCH)   *bp++ = 'N'; 
		if (def_search_type & SRCH_NO_REGEX)   *bp++ = 'R'; 
		if (def_search_type & SRCH_WRAP)       *bp++ = 'W'; 
		if (bp == buf)
			*bp++ = '-';
		*bp = '\0';
		parg.p_string = buf;
		error("search options: %s", &parg);
		break;
	}
}

#if LESSTEST
/*
 * Handler for the --tty option.
 */
	/*ARGSUSED*/
public void opt_ttyin_name(int type, char *s)
{
	switch (type)
	{
	case INIT:
		ttyin_name = s;
		is_tty = 1;
		break;
	}
}
#endif /*LESSTEST*/

public int chop_line(void)
{
	return (chopline || header_cols > 0 || header_lines > 0);
}

/*
 * Get the "screen window" size.
 */
public int get_swindow(void)
{
	if (swindow > 0)
		return (swindow);
	return (sc_height - header_lines + swindow);
}