2000/0817/port/dev.c (diff list | history)

port/dev.c on 1990/0227
1990/0227		#include "u.h"
1992/0321		#include "../port/lib.h"
1990/0227		#include "mem.h" #include "dat.h" #include "fns.h"
1992/0111		#include "../port/error.h"
1990/0227
1991/1220		extern ulong kerndate;
1990/0227		int devno(int c, int user) {
1992/1217		int i;
1990/0227
1997/0408		for(i = 0; devtab[i] != nil; i++) { if(devtab[i]->dc == c)
1992/1217		return i;
1990/0227		}
1997/0408		if(user == 0) panic("devno %C 0x%ux", c, c);
1992/1217
1997/0408		return -1;
1990/0227		} void
1998/0326		devdir(Chan *c, Qid qid, char *n, vlong length, char *user, long perm, Dir *db)
1990/0227		{ strcpy(db->name, n); db->qid = qid;
1997/0408		db->type = devtab[c->type]->dc;
1990/0227		db->dev = c->dev;
1990/11211		if(qid.path & CHDIR)
1990/0227		db->mode = CHDIR|perm; else db->mode = perm;
1993/0323		if(c->flag&CMSG) db->mode |= CHMOUNT;
1990/0227		db->atime = seconds();
1991/1220		db->mtime = kerndate;
1998/0326		db->length = length;
1993/1210		memmove(db->uid, user, NAMELEN); memmove(db->gid, eve, NAMELEN);
1990/0227		}
1999/1230		// // the zeroth element of the table MUST be the directory itself for .. //
1990/0227		int devgen(Chan *c, Dirtab *tab, int ntab, int i, Dir *dp) {
1999/1230		if(tab==0)
1990/0227		return -1;
1999/1230		if(i!=DEVDOTDOT){ if(i>=ntab) return -1; tab += i; }
1991/1109		devdir(c, tab->qid, tab->name, tab->length, eve, tab->perm, dp);
1990/0227		return 1; }
1997/0327		void devreset(void) { } void devinit(void) { } Chan*
1990/0227		devattach(int tc, char *spec) { Chan *c;
1993/0501		char buf[NAMELEN+4];
1990/0227		c = newchan();
1990/11211		c->qid = (Qid){CHDIR, 0};
1990/0227		c->type = devno(tc, 0);
1999/0629		sprint(buf, "#%C%s", tc, spec==nil? "" : spec); c->name = newcname(buf);
1990/0227		return c; }
1997/0327		Chan*
1990/0227		devclone(Chan *c, Chan *nc) {
1990/0329		if(c->flag & COPEN)
1997/0408		panic("clone of open file type %C\n", devtab[c->type]->dc);
1993/0501
1990/0227		if(nc == 0) nc = newchan();
1993/0501
1990/0227		nc->type = c->type;
1991/0421		nc->dev = c->dev;
1990/0227		nc->mode = c->mode; nc->qid = c->qid; nc->offset = c->offset; nc->flag = c->flag;
1998/0829		nc->mh = c->mh; if(c->mh != nil) incref(c->mh);
1991/0427		nc->mountid = c->mountid;
1991/0421		nc->aux = c->aux;
1990/0303		nc->mchan = c->mchan; nc->mqid = c->mqid;
1993/1013		nc->mcp = c->mcp;
1990/0227		return nc; } int devwalk(Chan *c, char *name, Dirtab *tab, int ntab, Devgen *gen) { long i; Dir dir; isdir(c); if(name[0]=='.' && name[1]==0) return 1;
1999/1230		if(name[0]=='.' && name[1]=='.' && name[2]==0){ (*gen)(c, tab, ntab, DEVDOTDOT, &dir); c->qid = dir.qid; return 1; }
1993/0501		for(i=0;; i++) {
1990/0227		switch((*gen)(c, tab, ntab, i, &dir)){ case -1:
1993/0501		strncpy(up->error, Enonexist, NAMELEN);
1990/0227		return 0; case 0: continue; case 1: if(strcmp(name, dir.name) == 0){ c->qid = dir.qid; return 1; } continue; }
1993/0501		}
1997/0327		return 0;
1991/0411		}
1990/0227		void devstat(Chan *c, char *db, Dirtab *tab, int ntab, Devgen *gen) { int i; Dir dir;
1999/0629		char *p, *elem;
1990/0227
1993/0330		for(i=0;; i++)
1990/0227		switch((*gen)(c, tab, ntab, i, &dir)){ case -1:
1990/11211		if(c->qid.path & CHDIR){
1999/0629		if(c->name == nil) elem = "???";
1999/0710		else if(strcmp(c->name->s, "/") == 0) elem = "/";
1999/0629		else for(elem=p=c->name->s; *p; p++)
1999/0724		if(*p == '/')
1999/0629		elem = p+1;
2000/0716		devdir(c, c->qid, elem, 0, eve, CHDIR|0555, &dir);
1990/0227		convD2M(&dir, db); return; }
1997/0327		print("%s %s: devstat %C %lux\n", up->text, up->user,
1997/0408		devtab[c->type]->dc, c->qid.path);
1997/0327
1991/0626		error(Enonexist);
1993/0330		case 0: break;
1990/0227		case 1:
1999/0122		if(c->qid.path == dir.qid.path) {
1993/0323		if(c->flag&CMSG) dir.mode |= CHMOUNT;
1990/0227		convD2M(&dir, db); return; } break; } } long devdirread(Chan *c, char *d, long n, Dirtab *tab, int ntab, Devgen *gen) {
1990/0821		long k, m;
1990/0227		Dir dir; k = c->offset/DIRLEN;
1993/0501		for(m=0; m<n; k++) {
1990/0227		switch((*gen)(c, tab, ntab, k, &dir)){ case -1:
1990/0821		return m;
1990/0227		case 0: c->offset += DIRLEN; break; case 1: convD2M(&dir, d);
1990/0821		m += DIRLEN;
1990/0227		d += DIRLEN; break; }
1993/0501		}
1990/0821		return m;
1990/0227		}
2000/0718		/* * error(Eperm) if open permission not granted for up->user. */ void devpermcheck(char *fileuid, ulong perm, int omode) { ulong t; static int access[] = { 0400, 0200, 0600, 0100 }; if(strcmp(up->user, fileuid) == 0) perm <<= 0; else if(strcmp(up->user, eve) == 0) perm <<= 3; else perm <<= 6; t = access[omode&3]; if((t&perm) != t) error(Eperm); }
1997/0327		Chan*
1990/0227		devopen(Chan *c, int omode, Dirtab *tab, int ntab, Devgen *gen) { int i; Dir dir;
1993/0501		for(i=0;; i++) {
1990/0227		switch((*gen)(c, tab, ntab, i, &dir)){ case -1: goto Return; case 0: break; case 1:
1999/0122		if(c->qid.path == dir.qid.path) {
2000/0718		devpermcheck(dir.uid, dir.mode, omode); goto Return;
1990/0227		} break; }
1993/0501		} Return:
1990/0227		c->offset = 0;
1990/11211		if((c->qid.path&CHDIR) && omode!=OREAD) error(Eperm);
1990/0227		c->mode = openmode(omode); c->flag |= COPEN; return c; }
1995/0108
1998/0512		void
1997/0327		devcreate(Chan*, char*, int, ulong) { error(Eperm); }
1995/0108		Block* devbread(Chan *c, long n, ulong offset) { Block *bp; bp = allocb(n); if(bp == 0) error(Enomem); if(waserror()) { freeb(bp); nexterror(); }
1997/0327		bp->wp += devtab[c->type]->read(c, bp->wp, n, offset);
1995/0108		poperror(); return bp; } long devbwrite(Chan *c, Block *bp, ulong offset) { long n;
2000/0817		if(waserror()) { freeb(bp); nexterror(); }
1997/0327		n = devtab[c->type]->write(c, bp->rp, BLEN(bp), offset);
2000/0817		poperror();
1995/0108		freeb(bp);
1998/0512		return n;
1995/0108		}
1997/0327		void devremove(Chan*) { error(Eperm); } void devwstat(Chan*, char*) { error(Eperm); }