/* * Reads gopher output from standard input, outputs * html on standard output. * Usage: gopher2html gopher-string *	where gopher-string is the string sent to *	the gopher server to get the document. * * Gopher protocol is described in rfc1436 */#include <u.h>#include <libc.h>char *cmd;int ifd;void errexit(char *s, ...){	static char buf[1024];	char *out;	print("<head><title>%s error</title></head>\n", cmd);	print("<body><h1>%s error</h1>\n", cmd);	out = doprint(buf, buf+sizeof(buf), s, (&s+1));	*out='\0';	print("%s</body>\n", buf);	exits("gopher error");}void wtext(char *buf, char *ebuf){	char *bp;	for(bp=buf;bp!=ebuf;bp++){		if(*bp=='<' || *bp=='>' || *bp=='&' || *bp=='"'){			if(bp!=buf) write(1, buf, bp-buf);			buf=bp+1;			switch(*bp){			case '<': print("&lt;"); break;			case '>': print("&gt;"); break;			case '&': print("&amp;"); break;			case '"': print("&quot;"); break;			}		}	}	if(bp!=buf) write(1, buf, bp-buf);}void copyfile(char *title){	char buf[1024];	int n;	print("<head><title>%s</title></head>\n", title);	print("<body><h1>%s</h1><pre>\n", title);	while((n=read(ifd, buf, sizeof buf))>0) wtext(buf, buf+n);	print("</pre></body>\n");}/* * A directory entry contains *	type name selector host port * all tab separated, except type and name (type is one character) */char ibuf[1024], *ibp, *eibuf;#define	EOF	(-1)int get(void){	int n;Again:	if(ibp==eibuf){		n=read(ifd, ibuf, sizeof(ibuf));		if(n<=0) return EOF;		eibuf=ibuf+n;		ibp=ibuf;	}	if(*ibp=='\r'){		ibp++;		goto Again;	}	return *ibp++&255;}char *escape(char *in){	static char out[516];	char *op, *eop;	eop=out+512;	op=out;	for(;*in;in++){		if(op<eop){			if(strchr("/$-_@.&!*'(),", *in)			|| 'a'<=*in && *in<='z'			|| 'A'<=*in && *in<='Z'			|| '0'<=*in && *in<='9')				*op++=*in;			else{				sprint(op, "%%%.2X", *in&255);				op+=3;			}		}	}	*op='\0';	return out;}void copydir(char *title){	int type, c;	char name[513], *ename;	char selector[513];	char host[513];	char port[513];	char *bp;	print("<head><title>%s</title></head>\n", title);	print("<body><h1>%s</h1><ul>\n", title);	for(;;){		type=get();		if(type==EOF || type=='.') break;		bp=name;		while((c=get())!=EOF && c!='\t') if(bp!=&name[512]) *bp++=c;		ename=bp;		bp=selector;		while((c=get())!=EOF && c!='\t') if(bp!=&selector[512]) *bp++=c;		*bp='\0';		bp=host;		while((c=get())!=EOF && c!='\t') if(bp!=&host[512]) *bp++=c;		*bp='\0';		bp=port;		while((c=get())!=EOF && c!='\t' && c!='\n') if(bp!=&port[512]) *bp++=c;		while(c!=EOF && c!='\n') c=get();		*bp='\0';		print("<li><a href=\"gopher://%s:%s/%c%s\">", host, port, type, escape(selector));		wtext(name, ename);		print("</a>\n");	}	print("</ul></body>\n");}void main(int argc, char *argv[]){	char dialstr[1024];	char *name;	cmd=argv[0];	if(argc!=4) errexit("Usage: %s host port selector", argv[0]);	sprint(dialstr, "tcp!%s!%s", argv[1], argv[2]);	ifd=dial(dialstr, 0, 0, 0);	if(ifd==-1) errexit("can't call %s:%s", argv[1], argv[2]);	switch(argv[3][0]){	case '/':		fprint(ifd, "\r\n");		copydir(argv[3]);		break;	case '\0':		fprint(ifd, "\r\n");		copydir(argv[1]);		break;	default:		fprint(ifd, "%s\r\n", argv[3]+1);		name=strrchr(argv[3], '/');		if(name==0) name=argv[3];		else name++;		switch(argv[3][0]){		default:	errexit("sorry, can't handle %s", argv[3]+1);		case '0':	copyfile(name); break;		case '7':	/* Item is an Index-Search server. */		case '1':	copydir(name); break;		}		break;	}	exits(0);}