/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include <draw.h>#include <thread.h>#include <cursor.h>#include <mouse.h>#include <keyboard.h>#include <frame.h>#include <fcall.h>#include <plumb.h>#include "dat.h"#include "fns.h" enum{	None = 0,	Fore = '+',	Back = '-',}; enum{	Char,	Line,}; intisaddrc(int r){	if(r && utfrune("0123456789+-/$.#,;", r)!=nil)		return TRUE;	return FALSE;} /* * quite hard: could be almost anything but white space, but we are a little conservative, * aiming for regular expressions of alphanumerics and no white space */intisregexc(int r){	if(r == 0)		return FALSE;	if(isalnum(r))		return TRUE;	if(utfrune("^+-.*?#,;[]()$", r)!=nil)		return TRUE;	return FALSE;} Rangenumber(Mntdir *md, Text *t, Range r, int line, int dir, int size, int *evalp){	uint q0, q1; 	if(size == Char){		if(dir == Fore)			line = r.q1+line;		else if(dir == Back){			if(r.q0==0 && line>0)				r.q0 = t->file->nc;			line = r.q0 - line;		}		if(line<0 || line>t->file->nc)			goto Rescue;		*evalp = TRUE;		return (Range){line, line};	}	q0 = r.q0;	q1 = r.q1;	switch(dir){	case None:		q0 = 0;		q1 = 0;	Forward:		while(line>0 && q1<t->file->nc)			if(textreadc(t, q1++) == '\n' || q1==t->file->nc)				if(--line > 0)					q0 = q1;		if(line > 0)			goto Rescue;		break;	case Fore:		if(q1 > 0)			while(q1<t->file->nc && textreadc(t, q1-1) != '\n')				q1++;		q0 = q1;		goto Forward;	case Back:		if(q0 < t->file->nc)			while(q0>0 && textreadc(t, q0-1)!='\n')				q0--;		q1 = q0;		while(line>0 && q0>0){			if(textreadc(t, q0-1) == '\n'){				if(--line >= 0)					q1 = q0;			}			--q0;		}		/* :1-1 is :0 = #0, but :1-2 is an error */		if(line > 1)			goto Rescue;		while(q0>0 && textreadc(t, q0-1)!='\n')			--q0;	}	*evalp = TRUE;	return (Range){q0, q1};     Rescue:	if(md != nil)		warning(nil, "address out of range\n");	*evalp = FALSE;	return r;}  Rangeregexp(Mntdir *md, Text *t, Range lim, Range r, Rune *pat, int dir, int *foundp){	int found;	Rangeset sel;	int q; 	if(pat[0] == '\0' && rxnull()){		warning(md, "no previous regular expression\n");		*foundp = FALSE;		return r;	}	if(pat[0] && rxcompile(pat) == FALSE){		*foundp = FALSE;		return r;	}	if(dir == Back)		found = rxbexecute(t, r.q0, &sel);	else{		if(lim.q0 < 0)			q = Infinity;		else			q = lim.q1;		found = rxexecute(t, nil, r.q1, q, &sel);	}	if(!found && md==nil)		warning(nil, "no match for regexp\n");	*foundp = found;	return sel.r[0];} Rangeaddress(Mntdir *md, Text *t, Range lim, Range ar, void *a, uint q0, uint q1, int (*getc)(void*, uint),  int *evalp, uint *qp){	int dir, size, npat;	int prevc, c, nc, n;	uint q;	Rune *pat;	Range r, nr; 	r = ar;	q = q0;	dir = None;	size = Line;	c = 0;	while(q < q1){		prevc = c;		c = (*getc)(a, q++);		switch(c){		default:			*qp = q-1;			return r;		case ';':			ar = r;			/* fall through */		case ',':			if(prevc == 0)	/* lhs defaults to 0 */				r.q0 = 0;			if(q>=q1 && t!=nil && t->file!=nil)	/* rhs defaults to $ */				r.q1 = t->file->nc;			else{				nr = address(md, t, lim, ar, a, q, q1, getc, evalp, &q);				r.q1 = nr.q1;			}			*qp = q;			return r;		case '+':		case '-':			if(*evalp && (prevc=='+' || prevc=='-'))				if((nc=(*getc)(a, q))!='#' && nc!='/' && nc!='?')					r = number(md, t, r, 1, prevc, Line, evalp);	/* do previous one */			dir = c;			break;		case '.':		case '$':			if(q != q0+1){				*qp = q-1;				return r;			}			if(*evalp)				if(c == '.')					r = ar;				else					r = (Range){t->file->nc, t->file->nc};			if(q < q1)				dir = Fore;			else				dir = None;			break;		case '#':			if(q==q1 || (c=(*getc)(a, q++))<'0' || '9'<c){				*qp = q-1;				return r;			}			size = Char;			/* fall through */		case '0': case '1': case '2': case '3': case '4':		case '5': case '6': case '7': case '8': case '9':			n = c -'0';			while(q<q1){				c = (*getc)(a, q++);				if(c<'0' || '9'<c){					q--;					break;				}				n = n*10+(c-'0');			}			if(*evalp)				r = number(md, t, r, n, dir, size, evalp);			dir = None;			size = Line;			break;		case '?':			dir = Back;			/* fall through */		case '/':			npat = 0;			pat = nil;			while(q<q1){				c = (*getc)(a, q++);				switch(c){				case '\n':					--q;					goto out;				case '\\':					pat = runerealloc(pat, npat+1);					pat[npat++] = c;					if(q == q1)						goto out;					c = (*getc)(a, q++);					break;				case '/':					goto out;				}				pat = runerealloc(pat, npat+1);				pat[npat++] = c;			}		    out:			pat = runerealloc(pat, npat+1);			pat[npat] = 0;			if(*evalp)				r = regexp(md, t, lim, r, pat, dir, evalp);			free(pat);			dir = None;			size = Line;			break;		}	}	if(*evalp && dir != None)		r = number(md, t, r, 1, dir, Line, evalp);	/* do previous one */	*qp = q;	return r;}