#include	"u.h"#include	"../port/lib.h"#include	"mem.h"#include	"dat.h"#include	"fns.h"#include	"../port/error.h"#include	<a.out.h>#include	<dynld.h>#include	<kernel.h> /* * TO DO *	- dynamic allocation of Dev.dc *	- inter-module dependencies *	- reference count on Dev to allow error("inuse") [or how else to do it] *	- is Dev.shutdown the right function to call?  Dev.config perhaps? */ #define	DBG	if(1) print#define	NATIVE  extern ulong ndevs; enum{	Qdir,	Qdynld,	Qdynsyms, 	DEVCHAR	= 'L',}; static Dirtab	dltab[] ={	".",			{Qdir, 0, QTDIR},	0,	DMDIR|0555,	"dynld",		{Qdynld},	0,	0644,	"dynsyms",	{Qdynsyms},	0,	0444,}; typedef struct Dyndev Dyndev; struct Dyndev{	char*	name;	/* device name (eg, "dynld") */	char*	tag;	/* version tag (eg, MD5 or SHA1 hash of content) */	char*	path;	/* file from whence it came */	Dynobj*	o;	Dev*	dev;	Dyndev*	next;}; static	Dyndev	*loaded;static	QLock	dllock; static	Dyndev**	finddyndev(char*);static	int	matched(Dyndev*, char*, char*); extern	Dynobj*	kdynloadfd(int, Dynsym*, int, ulong); static voiddlfree(Dyndev *l){	if(l != nil){		free(l->tag);		free(l->name);		free(l->path);		dynobjfree(l->o);		free(l);	}} static Dyndev*dlload(char *path, Dynsym *tab, int ntab){	Dyndev *l;	int fd; 	/* in Plan 9, would probably use Chan* interface here */	fd = kopen(path, OREAD);	if(fd < 0)		error("cannot open");	if(waserror()){		kclose(fd);		nexterror();	}	l = mallocz(sizeof(Dyndev), 1);	if(l == nil)		error(Enomem);	if(waserror()){		dlfree(l);		nexterror();	}	l->path = strdup(path);	if(l->path == nil)		error(Enomem);	l->o = kdynloadfd(fd, tab, ntab, 0);	if(l->o == nil)		error(up->env->errstr);	poperror();	poperror();	kclose(fd);	return l;} static voiddevload(char *name, char *path, char *tag){	int i;	Dyndev *l, **lp;	Dev *dev;	char tabname[32]; 	lp = finddyndev(name);	if(*lp != nil)		error("already loaded");	/* i'm assuming the name (eg, "cons") is to be unique */	l = dlload(path, _exporttab, dyntabsize(_exporttab));	if(waserror()){		dlfree(l);		nexterror();	}	snprint(tabname, sizeof(tabname), "%sdevtab", name);	dev = dynimport(l->o, tabname, signof(*dev));	if(dev == nil)		errorf("can't find %sdevtab in module", name);	kstrdup(&l->name, name);	kstrdup(&l->tag, tag != nil? tag: "");	if(dev->name == nil)		dev->name = l->name;	else if(strcmp(dev->name, l->name) != 0)		errorf("module file has device %s", dev->name);	/* TO DO: allocate dev->dc dynamically (cf. brucee's driver) */	if(devno(dev->dc, 1) >= 0)		errorf("devchar %C already used", dev->dc);	for(i = 0; devtab[i] != nil; i++)		;	if(i >= ndevs || devtab[i+1] != nil)		error("device table full");#ifdef NATIVE	i = splhi();	dev->reset();	splx(i);#endif	dev->init();	l->dev = devtab[i] = dev;	l->next = loaded;	loaded = l;			/* recently loaded ones first: good unload order? */	poperror();} static Dyndev**finddyndev(char *name){	Dyndev *l, **lp; 	for(lp = &loaded; (l = *lp) != nil; lp = &l->next)		if(strcmp(l->name, name) == 0)			break;	return lp;} static intmatched(Dyndev *l, char *path, char *tag){	if(path != nil && strcmp(l->path, path) != 0)		return 0;	if(tag != nil && strcmp(l->tag, tag) != 0)		return 0;	return 1;} static voiddevunload(char *name, char *path, char *tag){	int i;	Dyndev *l, **lp; 	lp = finddyndev(name);	l = *lp;	if(l == nil)		error("not loaded");	if(!matched(l, path, tag))		error("path/tag mismatch");	for(i = 0; i < ndevs; i++)		if(l->dev == devtab[i]){			devtab[i] = nil;		/* TO DO: ensure driver is not currently in use */			break;		}#ifdef NATIVE	l->dev->shutdown();#endif	*lp = l->next;	dlfree(l);} static longreaddynld(void *a, ulong n, ulong offset){	char *p;	Dyndev *l;	int m, len; 	m = 0;	for(l = loaded; l != nil; l = l->next)		m += 48 + strlen(l->name) + strlen(l->path) + strlen(l->tag);	p = malloc(m);	if(p == nil)		error(Enomem);	if(waserror()){		free(p);		nexterror();	}	*p = 0;	len = 0;	for(l = loaded; l != nil; l = l->next)		if(l->dev)			len += snprint(p+len, m-len, "#%C\t%.8p\t%.8lud\t%q\t%q\t%q\n",					l->dev->dc, l->o->base, l->o->size, l->name, l->path, l->tag);	n = readstr(offset, a, n, p);	poperror();	free(p);	return n;} static longreadsyms(char *a, ulong n, ulong offset){	char *p;	Dynsym *t;	long l, nr; 	p = malloc(READSTR);	if(p == nil)		error(Enomem);	if(waserror()){		free(p);		nexterror();	}	nr = 0;	for(t = _exporttab; n > 0 && t->name != nil; t++){		l = snprint(p, READSTR, "%.8lux %.8lux %s\n", t->addr, t->sig, t->name);		if(offset >= l){			offset -= l;			continue;		}		l = readstr(offset, a, n, p);		offset = 0;		n -= l;		a += l;		nr += l;	}	poperror();	free(p);	return nr;} static Chan*dlattach(char *spec){	return devattach(DEVCHAR, spec);} static Walkqid*dlwalk(Chan *c, Chan *nc, char **name, int nname){	return devwalk(c, nc, name, nname, dltab, nelem(dltab), devgen);} static intdlstat(Chan *c, uchar *db, int n){	return devstat(c, db, n, dltab, nelem(dltab), devgen);} static Chan*dlopen(Chan *c, int omode){	return devopen(c, omode, dltab, nelem(dltab), devgen);} static voiddlclose(Chan *c){	USED(c);} static longdlread(Chan *c, void *a, long n, vlong voffset){	switch((ulong)c->qid.path){	case Qdir:		return devdirread(c, a, n, dltab, nelem(dltab), devgen);	case Qdynld:		return readdynld(a, n, voffset);	case Qdynsyms:		return readsyms(a, n, voffset);	default:		error(Egreg);	}	return n;} static longdlwrite(Chan *c, void *a, long n, vlong voffset){	Cmdbuf *cb;	char *name, *tag, *path; 	USED(voffset);	switch((ulong)c->qid.path){	case Qdynld:		cb = parsecmd(a, n);		qlock(&dllock);		if(waserror()){			qunlock(&dllock);			free(cb);			nexterror();		}		if(cb->nf < 3 || strcmp(cb->f[1], "dev") != 0)	/* only do devices */			cmderror(cb, Ebadctl);		name = cb->f[2];		path = nil;		if(cb->nf > 3)			path = cb->f[3];		tag = nil;		if(cb->nf > 4)			tag = cb->f[4];		if(strcmp(cb->f[0], "load") == 0){			if(path == nil)				cmderror(cb, "missing load path");			devload(name, path, tag);	/* TO DO: remaining parameters might be dependencies? */		}else if(strcmp(cb->f[0], "unload") == 0)			devunload(name, path, tag);		else			cmderror(cb, Ebadctl);		poperror();		qunlock(&dllock);		free(cb);		break;	default:		error(Egreg);	}	return n;} Dev dynlddevtab = {	DEVCHAR,	"dynld", 	devreset,	devinit,	devshutdown,	/* TO DO */	dlattach,	dlwalk,	dlstat,	dlopen,	devcreate,	dlclose,	dlread,	devbread,	dlwrite,	devbwrite,	devremove,	devwstat,};