/*  * 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 <auth.h>#include <fcall.h>#include <thread.h>#include <9p.h> static char Ebad[] = "something bad happened";static char Enomem[] = "no memory"; typedef struct Ramfile	Ramfile;struct Ramfile {	char *data;	int ndata;}; voidfsread(Req *r){	Ramfile *rf;	vlong offset;	long count; 	rf = r->fid->file->aux;	offset = r->ifcall.offset;	count = r->ifcall.count; //print("read %ld %lld\n", *count, offset);	if(offset >= rf->ndata){		r->ofcall.count = 0;		respond(r, nil);		return;	} 	if(offset+count >= rf->ndata)		count = rf->ndata - offset; 	memmove(r->ofcall.data, rf->data+offset, count);	r->ofcall.count = count;	respond(r, nil);} voidfswrite(Req *r){	void *v;	Ramfile *rf;	vlong offset;	long count; 	rf = r->fid->file->aux;	offset = r->ifcall.offset;	count = r->ifcall.count; 	if(offset+count >= rf->ndata){		v = realloc(rf->data, offset+count);		if(v == nil){			respond(r, Enomem);			return;		}		rf->data = v;		rf->ndata = offset+count;		r->fid->file->length = rf->ndata;	}	memmove(rf->data+offset, r->ifcall.data, count);	r->ofcall.count = count;	respond(r, nil);} voidfscreate(Req *r){	Ramfile *rf;	File *f; 	if(f = createfile(r->fid->file, r->ifcall.name, r->fid->uid, r->ifcall.perm, nil)){		rf = emalloc9p(sizeof *rf);		f->aux = rf;		r->fid->file = f;		r->ofcall.qid = f->qid;		respond(r, nil);		return;	}	respond(r, Ebad);} voidfsopen(Req *r){	Ramfile *rf; 	rf = r->fid->file->aux; 	if(rf && (r->ifcall.mode&OTRUNC)){		rf->ndata = 0;		r->fid->file->length = 0;	} 	respond(r, nil);} voidfsdestroyfile(File *f){	Ramfile *rf; //fprint(2, "clunk\n");	rf = f->aux;	if(rf){		free(rf->data);		free(rf);	}} Srv fs = {	.open=	fsopen,	.read=	fsread,	.write=	fswrite,	.create=	fscreate,}; voidusage(void){	fprint(2, "usage: ramfs [-D] [-s srvname] [-m mtpt]\n");	exits("usage");} voidmain(int argc, char **argv){	char *addr = nil;	char *srvname = nil;	char *mtpt = nil;	Qid q; 	fs.tree = alloctree(nil, nil, DMDIR|0777, fsdestroyfile);	q = fs.tree->root->qid; 	ARGBEGIN{	case 'D':		chatty9p++;		break;	case 'a':		addr = EARGF(usage());		break;	case 's':		srvname = EARGF(usage());		break;	case 'm':		mtpt = EARGF(usage());		break;	default:		usage();	}ARGEND; 	if(argc)		usage(); 	if(chatty9p)		fprint(2, "ramsrv.nopipe %d srvname %s mtpt %s\n", fs.nopipe, srvname, mtpt);	if(addr == nil && srvname == nil && mtpt == nil)		sysfatal("must specify -a, -s, or -m option");	if(addr)		listensrv(&fs, addr); 	if(srvname || mtpt)		postmountsrv(&fs, srvname, mtpt, MREPL|MCREATE);	exits(0);}