1993/1115/port/chan.c (diff list | history)

1990/0227/sys/src/9/port/chan.c:78,83 – 1990/0303/sys/src/9/port/chan.c:78,85 (short | long)
1990/0227		c->offset = 0; c->mnt = 0; c->stream = 0;
1990/0303		c->mchan = 0; c->mqid = 0;
1990/0227		return c; } unlock(&chanalloc);
1990/0303/sys/src/9/port/chan.c:149,155 – 1990/0321/sys/src/9/port/chan.c:149,155 (short | long)
1990/0227		Mtab *mt, *mz; Mount *mnt, *omnt, *nmnt, *pmnt; Pgrp *pg; int isnew;
1990/0321		int islast;
1990/0227		if(CHDIR & (old->qid^new->qid)) error(0, Emount);
1990/0303/sys/src/9/port/chan.c:157,166 – 1990/0321/sys/src/9/port/chan.c:157,171
1990/0227		error(0, Emount); mz = 0; isnew = 0;
1990/0321		islast = 0; mnt = 0;
1990/0227		pg = u->p->pgrp; lock(pg); if(waserror()){
1990/0321		if(mnt){ mnt->c = 0; /* caller will close new */ closemount(mnt); }
1990/0227		unlock(pg); nexterror(); }
1990/0303/sys/src/9/port/chan.c:171,188 – 1990/0321/sys/src/9/port/chan.c:176,193
1990/0227		for(i=0; i<pg->nmtab; i++,mt++){ if(mt->c==0 && mz==0) mz = mt; else if(eqchan(mt->c, old, CHDIR|QPATH))
1990/0321		else if(eqchan(mt->c, old, CHDIR|QPATH)){ mz = 0;
1990/0227		goto Found;
1990/0321		}
1990/0227		} isnew = 1; if(mz == 0){ if(i == conf.nmtab) error(0, Enomount); mz = &pg->mtab[i]; pg->nmtab++;
1990/0321		islast++;
1990/0227		} mz->mnt = 0; mz->c = old; mt = mz; Found:
1990/0303/sys/src/9/port/chan.c:244,251 – 1990/0321/sys/src/9/port/chan.c:249,260
1990/0227		} incref(new); if(isnew)
1990/0321		if(mz){ mz->c = old;
1990/0227		incref(old);
1990/0321		} if(islast) pg->nmtab++;
1990/0227		unlock(pg); poperror(); return mnt->mountid;
1990/0303/sys/src/9/port/chan.c:286,292 – 1990/0321/sys/src/9/port/chan.c:295,301
1990/0227		Found: lock(pg); if(!eqchan(mt->c, c, CHDIR|QPATH)){ /* table changed underfoot */ print("domount: changed underfoot?\n");
1990/0321		pprint("domount: changed underfoot?\n");
1990/0227		unlock(pg); return c; }
1990/0303/sys/src/9/port/chan.c:333,339 – 1990/0321/sys/src/9/port/chan.c:342,348
1990/0227		goto Notfound; } if(c->mountid != mnt->mountid){ print("walk: changed underfoot?\n");
1990/0321		pprint("walk: changed underfoot?\n");
1990/0227		unlock(pg); goto Notfound; }
1990/0303/sys/src/9/port/chan.c:353,358 – 1990/0321/sys/src/9/port/chan.c:362,368
1990/0227		if(!first) close(c); nc->mnt = mnt;
1990/0321		nc->mountid = mnt->mountid;
1990/0227		c = nc; first = 0; goto Again;
1990/0303/sys/src/9/port/chan.c:391,397 – 1990/0321/sys/src/9/port/chan.c:401,407
1990/0227		} mnt = c->mnt; if(c->mountid != mnt->mountid){ print("createdir: changed underfoot?\n");
1990/0321		pprint("createdir: changed underfoot?\n");
1990/0227		error(0, Enocreate); } do{
1990/0321/sys/src/9/port/chan.c:490,497 – 1990/0513/sys/src/9/port/chan.c:490,499 (short | long)
1990/0227		switch(amode){ case Aaccess: if((nc=walk(c, elem, mntok)) == 0)
1990/0513		if((nc=walk(c, elem, mntok)) == 0){ print("%d pc %lux\n", u->nerrlab, u->errlab[u->nerrlab-1].pc);
1990/0227		error(0, Enonexist);
1990/0513		}
1990/0227		c = nc; break;
1990/0513/sys/src/9/port/chan.c:490,499 – 1990/0515/sys/src/9/port/chan.c:490,497 (short | long)
1990/0227		switch(amode){ case Aaccess:
1990/0513		if((nc=walk(c, elem, mntok)) == 0){ print("%d pc %lux\n", u->nerrlab, u->errlab[u->nerrlab-1].pc);
1990/0515		if((nc=walk(c, elem, mntok)) == 0)
1990/0227		error(0, Enonexist);
1990/0513		}
1990/0227		c = nc; break;
1990/0515/sys/src/9/port/chan.c:134,140 – 1990/0603/sys/src/9/port/chan.c:134,140 (short | long)
1990/0227		nmnt->mountid = omnt->mountid; nmnt->next = omnt->next; if(nmnt->next) incref(nmnt);
1990/0603		incref(nmnt->next);
1990/0227		nmnt->c = omnt->c; incref(nmnt->c); omnt->ref--;
1990/0515/sys/src/9/port/chan.c:207,220 – 1990/0603/sys/src/9/port/chan.c:207,218
1990/0227		/* fall through */ case MREPL: omnt = mt->mnt; if(omnt) incref(omnt); mnt->next = omnt;
1990/0603		mnt->next = mt->mnt;
1990/0227		mt->mnt = mnt; mnt->term = 1; if((flag&MORDER) == MBEFORE) mnt->term = 0;
1990/0603		else mnt->term = 1;
1990/0227		break; /*
1990/0603/sys/src/9/port/chan.c:127,133 – 1990/0617/sys/src/9/port/chan.c:127,132 (short | long)
1990/0227		{ Mount *nmnt; print("mount copy on write\n"); nmnt = newmount(); lock(nmnt); nmnt->term = omnt->term;
1990/0617/sys/src/9/port/chan.c:72,77 – 1990/0707/sys/src/9/port/chan.c:72,78 (short | long)
1990/0227		lock(&chanalloc); if(c = chanalloc.free){ /* assign = */ chanalloc.free = c->next;
1990/0707		c->type = 0; /* if closed before changed, this calls rooterror, a nop */
1990/0227		c->flag = 0; c->ref = 1; unlock(&chanalloc);
1990/0707/sys/src/9/port/chan.c:447,453 – 1990/08141/sys/src/9/port/chan.c:447,453 (short | long)
1990/0227		mntok = 0; if(!((ulong)name & KZERO)) validaddr((ulong)(name+1), 2, 0); if(name[1]=='|' || ('A'<=name[1] && name[1]<='Z'))
1990/08141		if(name[1]=='|' || name[1]=='M')
1990/0227		error(0, Enonexist); t = devno(name[1], 1); if(t == -1)
1990/0707/sys/src/9/port/chan.c:511,516 – 1990/08141/sys/src/9/port/chan.c:511,518
1990/0227		c = nc; Open: c = (*devtab[c->type].open)(c, omode);
1990/08141		if(omode & OCEXEC) c->flag |= CCEXEC;
1990/0227		break; case Amount:
1990/0707/sys/src/9/port/chan.c:533,538 – 1990/08141/sys/src/9/port/chan.c:535,542
1990/0227		if((c->flag&(CMOUNT|CCREATE)) == CMOUNT) c = createdir(c); (*devtab[c->type].create)(c, elem, omode, perm);
1990/08141		if(omode & OCEXEC) c->flag |= CCEXEC;
1990/0227		break; default:
1990/08141/sys/src/9/port/chan.c:340,346 – 1990/0820/sys/src/9/port/chan.c:340,346 (short | long)
1990/0227		goto Notfound; } if(c->mountid != mnt->mountid){
1990/0321		pprint("walk: changed underfoot?\n");
1990/0820		pprint("walk: changed underfoot? '%s'\n", name);
1990/0227		unlock(pg); goto Notfound; }
1990/08141/sys/src/9/port/chan.c:431,442 – 1990/0820/sys/src/9/port/chan.c:431,443
1990/0227		{ Chan *c, *nc; int t; int mntok;
1990/0820		int mntok, isdot;
1990/0227		char *elem = u->elem; if(name[0] == 0) error(0, Enonexist); mntok = 1;
1990/0820		isdot = 0;
1990/0227		if(name[0] == '/'){ c = clone(u->slash, 0); /*
1990/08141/sys/src/9/port/chan.c:459,466 – 1990/0820/sys/src/9/port/chan.c:460,471
1990/0227		}else name = nextelem(name, elem); c = (*devtab[t].attach)(elem); }else
1990/0820		}else{
1990/0227		c = clone(u->dot, 0);
1990/0820		name = skipslash(name); /* eat leading ./ */ if(*name == 0) isdot = 1; }
1990/0227		if(waserror()){ close(c);
1990/08141/sys/src/9/port/chan.c:468,475 – 1990/0820/sys/src/9/port/chan.c:473,481
1990/0227		} name = nextelem(name, elem); if(mntok) if(!(amode==Amount && elem[0]==0)) /* don't domount on dot or slash */
1990/0820		if(mntok && !isdot) if(!(amode==Amount && elem[0]==0)) /* don't domount on slash */
1990/0227		c = domount(c); /* see case Atodir below */ /*
1990/08141/sys/src/9/port/chan.c:482,487 – 1990/0820/sys/src/9/port/chan.c:488,494
1990/0227		c = nc; name = nextelem(name, elem); }
1990/0820
1990/0227		/* * Last element; act according to type of access. */
1990/08141/sys/src/9/port/chan.c:488,496 – 1990/0820/sys/src/9/port/chan.c:495,507
1990/0227		switch(amode){ case Aaccess:
1990/0515		if((nc=walk(c, elem, mntok)) == 0)
1990/0227		error(0, Enonexist); c = nc;
1990/0820		if(isdot) c = domount(c); else{ if((nc=walk(c, elem, mntok)) == 0) error(0, Enonexist); c = nc; }
1990/0227		break; case Atodir:
1990/08141/sys/src/9/port/chan.c:506,514 – 1990/0820/sys/src/9/port/chan.c:517,529
1990/0227		break; case Aopen: if((nc=walk(c, elem, mntok)) == 0) error(0, Enonexist); c = nc;
1990/0820		if(isdot) c = domount(c); else{ if((nc=walk(c, elem, mntok)) == 0) error(0, Enonexist); c = nc; }
1990/0227		Open: c = (*devtab[c->type].open)(c, omode);
1990/08141		if(omode & OCEXEC)
1990/08141/sys/src/9/port/chan.c:527,532 – 1990/0820/sys/src/9/port/chan.c:542,549
1990/0227		break; case Acreate:
1990/0820		if(isdot) error(0, Eisdir);
1990/0227		if((nc=walk(c, elem, 1)) != 0){ c = nc; omode |= OTRUNC;
1990/08141/sys/src/9/port/chan.c:552,561 – 1990/0820/sys/src/9/port/chan.c:569,587
1990/0227		char* skipslash(char *name) {
1990/0820		Again:
1990/0227		while(*name == '/'){ if(((ulong)name&KZERO)==0 && (((ulong)name+1)&(BY2PG-1))==0) validaddr((ulong)name+1, 1, 0); name++;
1990/0820		} if(*name == '.'){ if(((ulong)name&KZERO)==0 && (((ulong)name+1)&(BY2PG-1))==0) validaddr((ulong)name+1, 1, 0); if(name[1]==0 || name[1]=='/'){ name++; goto Again; }
1990/0227		} return name; }
1990/0820/sys/src/9/port/chan.c:432,441 – 1990/0821/sys/src/9/port/chan.c:432,457 (short | long)
1990/0227		Chan *c, *nc; int t;
1990/0820		int mntok, isdot;
1990/0227		char *elem = u->elem;
1990/0821		char *p; char *elem;
1990/0227		if(name[0] == 0) error(0, Enonexist);
1990/0821		/* * Make sure all of name is o.k. first byte is validated * externally so if it's a kernel address we know it's o.k. */ if(!((ulong)name & KZERO)){ p = name; t = BY2PG-((ulong)p&(BY2PG-1)); while(vmemchr(p, 0, t) == 0){ p += t; t = BY2PG; } } elem = u->elem;
1990/0227		mntok = 1;
1990/0820		isdot = 0;
1990/0227		if(name[0] == '/'){
1990/0820/sys/src/9/port/chan.c:446,453 – 1990/0821/sys/src/9/port/chan.c:462,467
1990/0227		name = skipslash(name); }else if(name[0] == '#'){ mntok = 0; if(!((ulong)name & KZERO)) validaddr((ulong)(name+1), 2, 0);
1990/08141		if(name[1]=='|' || name[1]=='M')
1990/0227		error(0, Enonexist); t = devno(name[1], 1);
1990/0820/sys/src/9/port/chan.c:570,588 – 1990/0821/sys/src/9/port/chan.c:584,595
1990/0227		skipslash(char *name) {
1990/0820		Again:
1990/0227		while(*name == '/'){ if(((ulong)name&KZERO)==0 && (((ulong)name+1)&(BY2PG-1))==0) validaddr((ulong)name+1, 1, 0);
1990/0821		while(*name == '/')
1990/0227		name++;
1990/0821		if(*name=='.' && (name[1]==0 || name[1]=='/')){ name++; goto Again;
1990/0820		} if(*name == '.'){ if(((ulong)name&KZERO)==0 && (((ulong)name+1)&(BY2PG-1))==0) validaddr((ulong)name+1, 1, 0); if(name[1]==0 || name[1]=='/'){ name++; goto Again; }
1990/0227		} return name; }
1990/0820/sys/src/9/port/chan.c:600,606 – 1990/0821/sys/src/9/port/chan.c:607,612
1990/0227		* name[0] should not be a slash. * Advance name to next element in path, copying current element into elem. * Return pointer to next element, skipping slashes. * &name[0] is known to be a valid address. */ char* nextelem(char *name, char *elem)
1990/0820/sys/src/9/port/chan.c:610,618 – 1990/0821/sys/src/9/port/chan.c:616,624
1990/0227		if(*name == '/') error(0, Efilename); end = vmemchr(name, 0, NAMELEN);
1990/0821		end = memchr(name, 0, NAMELEN);
1990/0227		if(end == 0){ end = vmemchr(name, '/', NAMELEN);
1990/0821		end = memchr(name, '/', NAMELEN);
1990/0227		if(end == 0) error(0, Efilename); }else{
1990/0821/sys/src/9/port/chan.c:96,106 – 1990/0907/sys/src/9/port/chan.c:96,109 (short | long)
1990/0227		void close(Chan *c) {
1990/0907		if(c->flag & CFREE) panic("close");
1990/0227		if(decref(c) == 0){ if(!waserror()){ (*devtab[c->type].close)(c); poperror(); }
1990/0907		c->flag = CFREE;
1990/0227		lock(&chanalloc); c->next = chanalloc.free; chanalloc.free = c;
1990/0907/sys/src/9/port/chan.c:372,382 – 1990/0914/sys/src/9/port/chan.c:372,392 (short | long)
1990/0227		if(name[0]) /* walk succeeded */ c->flag &= ~CMOUNT;
1990/0914		if(domnt){ if(waserror()){ print("domount error\n"); if(!first) close(c); return 0; } c = domount(c); poperror(); }
1990/0227		if(!first) close(ac); if(domnt) return domount(c);
1990/0914
1990/0227		return c; Notfound:
1990/0907/sys/src/9/port/chan.c:425,430 – 1990/0914/sys/src/9/port/chan.c:435,445
1990/0227		return nc; }
1990/0914		void saveregisters(void) { }
1990/0227		/* * Turn a name into a channel. * &name[0] is known to be a valid address. It may be a kernel address.
1990/0907/sys/src/9/port/chan.c:542,547 – 1990/0914/sys/src/9/port/chan.c:557,563
1990/0820		c = nc; }
1990/0227		Open:
1990/0914		saveregisters(); /* else error() in open has wrong value of c saved */
1990/0227		c = (*devtab[c->type].open)(c, omode);
1990/08141		if(omode & OCEXEC) c->flag |= CCEXEC;
1990/0914/sys/src/9/port/chan.c:374,380 – 1990/09141/sys/src/9/port/chan.c:374,379 (short | long)
1990/0227
1990/0914		if(domnt){ if(waserror()){ print("domount error\n"); if(!first) close(c); return 0;
1990/09141/sys/src/9/port/chan.c:479,485 – 1990/1009/sys/src/9/port/chan.c:479,485 (short | long)
1990/0227		name = skipslash(name); }else if(name[0] == '#'){ mntok = 0;
1990/08141		if(name[1]=='|' || name[1]=='M')
1990/1009		if(name[1]=='M')
1990/0227		error(0, Enonexist); t = devno(name[1], 1); if(t == -1)
1990/1009/sys/src/9/port/chan.c:14,32 – 1990/1104/sys/src/9/port/chan.c:14,36 (short | long)
1990/0227		int incref(Ref *r) {
1990/1104		int x;
1990/0227		lock(r); r->ref++;
1990/1104		x = ++r->ref;
1990/0227		unlock(r); return r->ref;
1990/1104		return x;
1990/0227		} int decref(Ref *r) {
1990/1104		int x;
1990/0227		lock(r); r->ref--;
1990/1104		x = --r->ref;
1990/0227		unlock(r); return r->ref;
1990/1104		return x;
1990/0227		} void
1990/1104/sys/src/9/port/chan.c:80,90 – 1990/11211/sys/src/9/port/chan.c:80,91 (short | long)
1990/0227		c->flag = 0; c->ref = 1; unlock(&chanalloc);
1990/11211		c->dev = 0;
1990/0227		c->offset = 0; c->mnt = 0; c->stream = 0;
1990/0303		c->mchan = 0; c->mqid = 0;
1990/11211		c->mqid = (Qid){0, 0};
1990/0227		return c; } unlock(&chanalloc);
1990/1104/sys/src/9/port/chan.c:116,125 – 1990/11211/sys/src/9/port/chan.c:117,134
1990/0227		} int eqchan(Chan *a, Chan *b, long qmask)
1990/11211		eqqid(Qid a, Qid b)
1990/0227		{ if((a->qid^b->qid) & qmask)
1990/11211		return a.path==b.path && a.vers==b.vers; } int eqchan(Chan *a, Chan *b, int pathonly) { if(a->qid.path != b->qid.path)
1990/0227		return 0;
1990/11211		if(!pathonly && a->qid.vers!=b->qid.vers) return 0;
1990/0227		if(a->type != b->type) return 0; if(a->dev != b->dev)
1990/1104/sys/src/9/port/chan.c:158,167 – 1990/11211/sys/src/9/port/chan.c:167,176
1990/0227		Pgrp *pg;
1990/0321		int islast;
1990/0227		if(CHDIR & (old->qid^new->qid)) error(0, Emount); if((old->qid&CHDIR)==0 && (flag&MORDER)!=MREPL) error(0, Emount);
1990/11211		if(CHDIR & (old->qid.path^new->qid.path)) error(Emount); if((old->qid.path&CHDIR)==0 && (flag&MORDER)!=MREPL) error(Emount);
1990/0227		mz = 0;
1990/0321		islast = 0;
1990/1104/sys/src/9/port/chan.c:190,196 – 1990/11211/sys/src/9/port/chan.c:199,205
1990/0227		} if(mz == 0){ if(i == conf.nmtab) error(0, Enomount);
1990/11211		error(Enomount);
1990/0227		mz = &pg->mtab[i];
1990/0321		islast++;
1990/0227		}
1990/1104/sys/src/9/port/chan.c:210,216 – 1990/11211/sys/src/9/port/chan.c:219,225
1990/0227		*/ case MBEFORE: if(mt->mnt == 0) error(0, Enotunion);
1990/11211		error(Enotunion);
1990/0227		/* fall through */ case MREPL:
1990/1104/sys/src/9/port/chan.c:227,233 – 1990/11211/sys/src/9/port/chan.c:236,242
1990/0227		*/ case MAFTER: if(mt->mnt == 0) error(0, Enotunion);
1990/11211		error(Enotunion);
1990/0227		omnt = mt->mnt; pmnt = 0; while(!omnt->term){
1990/1104/sys/src/9/port/chan.c:416,426 – 1990/11211/sys/src/9/port/chan.c:425,435
1990/0227		mnt = c->mnt; if(c->mountid != mnt->mountid){
1990/0321		pprint("createdir: changed underfoot?\n");
1990/0227		error(0, Enocreate);
1990/11211		error(Enocreate);
1990/0227		} do{ if(mnt->term) error(0, Enocreate);
1990/11211		error(Enocreate);
1990/0227		mnt = mnt->next; }while(!(mnt->c->flag&CCREATE)); mc = mnt->c;
1990/1104/sys/src/9/port/chan.c:457,463 – 1990/11211/sys/src/9/port/chan.c:466,472
1990/0821		char *elem;
1990/0227		if(name[0] == 0) error(0, Enonexist);
1990/11211		error(Enonexist);
1990/0821		/* * Make sure all of name is o.k. first byte is validated
1990/1104/sys/src/9/port/chan.c:484,493 – 1990/11211/sys/src/9/port/chan.c:493,502
1990/0227		}else if(name[0] == '#'){ mntok = 0;
1990/1009		if(name[1]=='M')
1990/0227		error(0, Enonexist);
1990/11211		error(Enonexist);
1990/0227		t = devno(name[1], 1); if(t == -1) error(0, Ebadsharp);
1990/11211		error(Ebadsharp);
1990/0227		name += 2; if(*name == '/'){ name = skipslash(name);
1990/1104/sys/src/9/port/chan.c:519,525 – 1990/11211/sys/src/9/port/chan.c:528,534
1990/0227		*/ while(*name){ if((nc=walk(c, elem, mntok)) == 0) error(0, Enonexist);
1990/11211		error(Enonexist);
1990/0227		c = nc; name = nextelem(name, elem); }
1990/1104/sys/src/9/port/chan.c:534,540 – 1990/11211/sys/src/9/port/chan.c:543,549
1990/0820		c = domount(c); else{ if((nc=walk(c, elem, mntok)) == 0) error(0, Enonexist);
1990/11211		error(Enonexist);
1990/0820		c = nc; }
1990/0227		break;
1990/1104/sys/src/9/port/chan.c:545,554 – 1990/11211/sys/src/9/port/chan.c:554,563
1990/0227		* so one may mount on / or . and see the effect. */ if((nc=walk(c, elem, 0)) == 0) error(0, Enonexist);
1990/11211		error(Enonexist);
1990/0227		c = nc; if(!(c->qid & CHDIR)) error(0, Enotdir);
1990/11211		if(!(c->qid.path & CHDIR)) error(Enotdir);
1990/0227		break; case Aopen:
1990/1104/sys/src/9/port/chan.c:556,562 – 1990/11211/sys/src/9/port/chan.c:565,571
1990/0820		c = domount(c); else{ if((nc=walk(c, elem, mntok)) == 0) error(0, Enonexist);
1990/11211		error(Enonexist);
1990/0820		c = nc; }
1990/0227		Open:
1990/1104/sys/src/9/port/chan.c:573,585 – 1990/11211/sys/src/9/port/chan.c:582,594
1990/0227		* the replacement. */ if((nc=walk(c, elem, 0)) == 0) error(0, Enonexist);
1990/11211		error(Enonexist);
1990/0227		c = nc; break; case Acreate:
1990/0820		if(isdot) error(0, Eisdir);
1990/11211		error(Eisdir);
1990/0227		if((nc=walk(c, elem, 1)) != 0){ c = nc; omode |= OTRUNC;
1990/1104/sys/src/9/port/chan.c:637,648 – 1990/11211/sys/src/9/port/chan.c:646,657
1990/0227		char *end, *e; if(*name == '/') error(0, Efilename);
1990/11211		error(Efilename);
1990/0821		end = memchr(name, 0, NAMELEN);
1990/0227		if(end == 0){
1990/0821		end = memchr(name, '/', NAMELEN);
1990/0227		if(end == 0) error(0, Efilename);
1990/11211		error(Efilename);
1990/0227		}else{ e = memchr(name, '/', end-name); if(e)
1990/1104/sys/src/9/port/chan.c:651,657 – 1990/11211/sys/src/9/port/chan.c:660,666
1990/0227		while(name < end){ c = *name++; if((c&0x80) || isfrog[c]) error(0, Ebadchar);
1990/11211		error(Ebadchar);
1990/0227		*elem++ = c; } *elem = 0;
1990/1104/sys/src/9/port/chan.c:661,667 – 1990/11211/sys/src/9/port/chan.c:670,676
1990/0227		void isdir(Chan *c) { if(c->qid & CHDIR)
1990/11211		if(c->qid.path & CHDIR)
1990/0227		return; error(0, Enotdir);
1990/11211		error(Enotdir);
1990/0227		}
1990/11211/sys/src/9/port/chan.c:192,198 – 1990/1122/sys/src/9/port/chan.c:192,198 (short | long)
1990/0227		for(i=0; i<pg->nmtab; i++,mt++){ if(mt->c==0 && mz==0) mz = mt;
1990/0321		else if(eqchan(mt->c, old, CHDIR|QPATH)){
1990/1122		else if(eqchan(mt->c, old, 1)){
1990/0321		mz = 0;
1990/0227		goto Found;
1990/0321		}
1990/11211/sys/src/9/port/chan.c:296,302 – 1990/1122/sys/src/9/port/chan.c:296,302
1990/0227		*/ mt = pg->mtab; for(i=0; i<pg->nmtab; i++,mt++) if(mt->c && eqchan(mt->c, c, CHDIR|QPATH))
1990/1122		if(mt->c && eqchan(mt->c, c, 1))
1990/0227		goto Found; /* * No; c is unaffected
1990/11211/sys/src/9/port/chan.c:308,314 – 1990/1122/sys/src/9/port/chan.c:308,314
1990/0227		*/ Found: lock(pg); if(!eqchan(mt->c, c, CHDIR|QPATH)){ /* table changed underfoot */
1990/1122		if(!eqchan(mt->c, c, 1)){ /* table changed underfoot */
1990/0321		pprint("domount: changed underfoot?\n");
1990/0227		unlock(pg); return c;
1990/1122/sys/src/9/port/chan.c:99,118 – 1991/0413/sys/src/9/port/chan.c:99,126 (short | long)
1990/0227		} void
1991/0413		freechan(Chan *c) { c->flag = CFREE; lock(&chanalloc); c->next = chanalloc.free; chanalloc.free = c; unlock(&chanalloc); } void
1990/0227		close(Chan *c) {
1990/0907		if(c->flag & CFREE) panic("close");
1990/0227		if(decref(c) == 0){ if(!waserror()){ (*devtab[c->type].close)(c); poperror();
1991/0413		if(waserror()) { freechan(c); nexterror();
1990/0227		}
1990/0907		c->flag = CFREE;
1990/0227		lock(&chanalloc); c->next = chanalloc.free; chanalloc.free = c; unlock(&chanalloc);
1991/0413		(*devtab[c->type].close)(c); freechan(c); poperror();
1990/0227		} }
1991/0413/sys/src/9/port/chan.c:101,111 – 1991/0414/sys/src/9/port/chan.c:101,113 (short | long)
1990/0227		void
1991/0413		freechan(Chan *c) { c->flag = CFREE; lock(&chanalloc); c->next = chanalloc.free; chanalloc.free = c; unlock(&chanalloc);
1991/0414		if(decref(c) == 0){ c->flag = CFREE; lock(&chanalloc); c->next = chanalloc.free; chanalloc.free = c; unlock(&chanalloc); }
1991/0413		} void
1991/0413/sys/src/9/port/chan.c:114,126 – 1991/0414/sys/src/9/port/chan.c:116,130
1990/0907		if(c->flag & CFREE) panic("close");
1990/0227		if(decref(c) == 0){
1991/0413		if(waserror()) { freechan(c); nexterror();
1991/0414		if(!waserror()) { (*devtab[c->type].close)(c); poperror();
1990/0227		}
1991/0413		(*devtab[c->type].close)(c); freechan(c); poperror();
1991/0414		c->flag = CFREE; lock(&chanalloc); c->next = chanalloc.free; chanalloc.free = c; unlock(&chanalloc);
1990/0227		} }
1991/0414/sys/src/9/port/chan.c:530,537 – 1991/0416/sys/src/9/port/chan.c:530,540 (short | long)
1990/0227		name = nextelem(name, elem);
1990/0820		if(mntok && !isdot) if(!(amode==Amount && elem[0]==0)) /* don't domount on slash */
1991/0416		/* * If mounting, don't follow the mount entry for root or the * current directory. */ if(mntok && !isdot && !(amode==Amount && elem[0]==0))
1990/0227		c = domount(c); /* see case Atodir below */ /*
1991/0414/sys/src/9/port/chan.c:548,554 – 1991/0416/sys/src/9/port/chan.c:551,556
1990/0227		/* * Last element; act according to type of access. */                  switch(amode){ case Aaccess:
1990/0820		if(isdot)
1991/0416/sys/src/9/port/chan.c:84,89 – 1991/0421/sys/src/9/port/chan.c:84,91 (short | long)
1990/0227		c->offset = 0; c->mnt = 0; c->stream = 0;
1991/0421		c->aux = 0; c->mntindex = 0;
1990/0303		c->mchan = 0;
1990/11211		c->mqid = (Qid){0, 0};
1990/0227		return c;
1991/0421/sys/src/9/port/chan.c:11,16 – 1991/0423/sys/src/9/port/chan.c:11,28 (short | long)
1990/0227		Chan *free; }chanalloc;
1991/0423		/* * used by namec, domount, and walk to point * to the current mount entry during name resolution */ typedef struct Finger Finger; struct Finger { Chan *c; /* channel we're walking */ int needcl; /* true if we need to clone c before using it */ Mount *mnt; /* last mount point we ran traversed */ ulong mountid; /* id of that mount point */ };
1990/0227		int incref(Ref *r) {
1991/0421/sys/src/9/port/chan.c:83,91 – 1991/0423/sys/src/9/port/chan.c:95,101
1990/11211		c->dev = 0;
1990/0227		c->offset = 0; c->mnt = 0; c->stream = 0;
1991/0421		c->aux = 0; c->mntindex = 0;
1990/0303		c->mchan = 0;
1990/11211		c->mqid = (Qid){0, 0};
1990/0227		return c;
1991/0421/sys/src/9/port/chan.c:294,308 – 1991/0423/sys/src/9/port/chan.c:304,316
1990/0227		return (*devtab[c->type].clone)(c, nc); } Chan* domount(Chan *c)
1991/0423		void domount(Finger *f)
1990/0227		{ int i; ulong mntid; Mtab *mt; Mount *mnt; Pgrp *pg; Chan *nc, *mc;
1991/0423		Chan *mc;
1990/0227		pg = u->p->pgrp; /*
1991/0421/sys/src/9/port/chan.c:310,321 – 1991/0423/sys/src/9/port/chan.c:318,329
1990/0227		*/ mt = pg->mtab; for(i=0; i<pg->nmtab; i++,mt++)
1990/1122		if(mt->c && eqchan(mt->c, c, 1))
1991/0423		if(mt->c && eqchan(mt->c, f->c, 1))
1990/0227		goto Found; /* * No; c is unaffected */ return c;
1991/0423		return;
1990/0227		/* * Yes; move c through table
1991/0421/sys/src/9/port/chan.c:322,420 – 1991/0423/sys/src/9/port/chan.c:330,419
1990/0227		*/ Found: lock(pg);
1990/1122		if(!eqchan(mt->c, c, 1)){ /* table changed underfoot */
1991/0423		if(!eqchan(mt->c, f->c, 1)){ /* table changed underfoot */
1990/0321		pprint("domount: changed underfoot?\n");
1990/0227		unlock(pg); return c;
1991/0423		return;
1990/0227		} mnt = mt->mnt; mntid = mnt->mountid; mc = mnt->c;
1991/0423		f->mnt = mt->mnt; f->mountid = f->mnt->mountid; mc = mt->mnt->c;
1990/0227		incref(mc); unlock(pg); if(waserror()){ close(mc); nexterror(); } nc = clone(mc, 0); close(mc); poperror(); close(c); nc->mnt = mnt; nc->mountid = mntid; return nc;
1991/0423		close(f->c); f->c = mc; f->needcl = 1;
1990/0227		} Chan* walk(Chan *ac, char *name, int domnt)
1991/0423		int walk(Finger *f, char *name, int domnt)
1990/0227		{ Mount *mnt; int first = 1; Chan *c = ac; Chan *nc, *mc;
1991/0423		Mount *mnt = f->mnt; ulong mountid = f->mountid; Chan *c = f->c; Chan *mc;
1990/0227		Pgrp *pg = u->p->pgrp; /* * name may be empty if the file name is "/", "#c" etc. */ Again: if(name[0] && (*devtab[c->type].walk)(c, name)==0){ if(!(c->flag&CMOUNT)) goto Notfound; mnt = c->mnt; if(mnt == 0) panic("walk"); lock(pg); if(mnt->term){
1991/0423		if(name[0]){ for(;;){ if(!first || f->needcl){ mc = (*devtab[c->type].clwalk)(c, name); if(mc){ close(c); c = mc; break; } } else { if((*devtab[c->type].walk)(c, name) != 0){ break; } } if(!(c->flag&CMOUNT)) goto Notfound; if(mnt == 0) panic("walk"); /* ??? is this safe ??? */ lock(pg); if(mnt->term){ unlock(pg); goto Notfound; } if(mountid != mnt->mountid){ pprint("walk: changed underfoot? '%s'\n", name); unlock(pg); goto Notfound; } mnt = mnt->next; mountid = mnt->mountid; mc = mnt->c; incref(mc);
1990/0227		unlock(pg); goto Notfound; } if(c->mountid != mnt->mountid){
1990/0820		pprint("walk: changed underfoot? '%s'\n", name);
1990/0227		unlock(pg); goto Notfound; } mnt = mnt->next; mc = mnt->c; incref(mc); unlock(pg); if(waserror()){ close(mc); nexterror(); } if(mnt == 0) panic("walk 1"); nc = clone(mc, 0); close(mc); poperror(); if(!first) close(c); nc->mnt = mnt;
1990/0321		nc->mountid = mnt->mountid;
1990/0227		c = nc; first = 0; goto Again; }                  if(name[0]) /* walk succeeded */ c->flag &= ~CMOUNT;
1990/0914		if(domnt){ if(waserror()){ if(!first) close(c); return 0;
1991/0423		c = mc; first = 0;
1990/0914		} c = domount(c); poperror();
1991/0423		/* * we get here only if we have a cloned and walked * channel */ if(!first) close(f->c); f->c = c; f->needcl = 0; f->mnt = 0; c->flag &= ~CMOUNT;
1990/0914		}
1990/0227		if(!first) close(ac);
1991/0423		if(domnt) domount(f);
1990/0227
1991/0423		return 1;
1990/0914
1990/0227		return c;                  Notfound: if(!first) close(c);
1991/0421/sys/src/9/port/chan.c:422,435 – 1991/0423/sys/src/9/port/chan.c:421,434
1990/0227		} /* * c is a mounted non-creatable directory. find a creatable one.
1991/0423		* f->c is a mounted non-creatable directory. find a creatable one.
1990/0227		*/ Chan* createdir(Chan *c)
1991/0423		void createdir(Finger *f)
1990/0227		{ Mount *mnt; Pgrp *pg = u->p->pgrp; Chan *mc, *nc;
1991/0423		Chan *mc;
1990/0227		lock(pg); if(waserror()){
1991/0421/sys/src/9/port/chan.c:436,443 – 1991/0423/sys/src/9/port/chan.c:435,442
1990/0227		unlock(pg); nexterror(); } mnt = c->mnt; if(c->mountid != mnt->mountid){
1991/0423		mnt = f->mnt; if(f->mountid != mnt->mountid){
1990/0321		pprint("createdir: changed underfoot?\n");
1990/11211		error(Enocreate);
1990/0227		}
1991/0421/sys/src/9/port/chan.c:449,464 – 1991/0423/sys/src/9/port/chan.c:448,457
1990/0227		mc = mnt->c; incref(mc); unlock(pg); if(waserror()){ close(mc); nexterror(); } nc = clone(mc, 0); poperror(); close(c); close(mc); nc->mnt = mnt; return nc;
1991/0423		close(f->c); f->needcl = 1; f->c = mc;
1990/0227		}
1990/0914		void
1991/0421/sys/src/9/port/chan.c:466,471 – 1991/0423/sys/src/9/port/chan.c:459,477
1990/0914		{ }
1991/0423		void doclone(Finger *f) { Chan *nc; if(f->needcl == 0) return; nc = clone(f->c, 0); close(f->c); f->c = nc; f->needcl = 0; }
1990/0227		/* * Turn a name into a channel. * &name[0] is known to be a valid address. It may be a kernel address.
1991/0421/sys/src/9/port/chan.c:473,483 – 1991/0423/sys/src/9/port/chan.c:479,489
1990/0227		Chan* namec(char *name, int amode, int omode, ulong perm) { Chan *c, *nc; int t;
1990/0820		int mntok, isdot;
1990/0821		char *p; char *elem;
1991/0423		Finger f;
1990/0227		if(name[0] == 0)
1990/11211		error(Enonexist);
1991/0421/sys/src/9/port/chan.c:498,505 – 1991/0423/sys/src/9/port/chan.c:504,514
1990/0821		elem = u->elem;
1990/0227		mntok = 1;
1990/0820		isdot = 0;
1991/0423		f.mnt = 0;
1990/0227		if(name[0] == '/'){ c = clone(u->slash, 0);
1991/0423		f.c = u->slash; incref(f.c); f.needcl = 1;
1990/0227		/* * Skip leading slashes. */
1991/0421/sys/src/9/port/chan.c:517,525 – 1991/0423/sys/src/9/port/chan.c:526,537
1990/0227		elem[0]=0; }else name = nextelem(name, elem); c = (*devtab[t].attach)(elem);
1991/0423		f.c = (*devtab[t].attach)(elem); f.needcl = 0;
1990/0820		}else{
1990/0227		c = clone(u->dot, 0);
1991/0423		f.c = u->dot; incref(f.c); f.needcl = 1;
1990/0820		name = skipslash(name); /* eat leading ./ */ if(*name == 0) isdot = 1;
1991/0421/sys/src/9/port/chan.c:526,532 – 1991/0423/sys/src/9/port/chan.c:538,544
1990/0820		}
1990/0227		if(waserror()){ close(c);
1991/0423		close(f.c);
1990/0227		nexterror(); }
1991/0421/sys/src/9/port/chan.c:537,543 – 1991/0423/sys/src/9/port/chan.c:549,555
1991/0416		* current directory. */ if(mntok && !isdot && !(amode==Amount && elem[0]==0))
1990/0227		c = domount(c); /* see case Atodir below */
1991/0423		domount(&f); /* see case Atodir below */
1990/0227		/* * How to treat the last element of the name depends on the operation.
1991/0421/sys/src/9/port/chan.c:544,552 – 1991/0423/sys/src/9/port/chan.c:556,563
1990/0227		* Therefore do all but the last element by the easy algorithm. */ while(*name){ if((nc=walk(c, elem, mntok)) == 0)
1991/0423		if(walk(&f, elem, mntok) == 0)
1990/11211		error(Enonexist);
1990/0227		c = nc; name = nextelem(name, elem); }
1990/0820
1991/0421/sys/src/9/port/chan.c:556,566 – 1991/0423/sys/src/9/port/chan.c:567,576
1990/0227		switch(amode){ case Aaccess:
1990/0820		if(isdot) c = domount(c);
1991/0423		domount(&f);
1990/0820		else{ if((nc=walk(c, elem, mntok)) == 0)
1991/0423		if(walk(&f, elem, mntok) == 0)
1990/11211		error(Enonexist);
1990/0820		c = nc; }
1990/0227		break;
1991/0421/sys/src/9/port/chan.c:569,594 – 1991/0423/sys/src/9/port/chan.c:579,604
1990/0227		* Directories (e.g. for cd) are left before the mount point, * so one may mount on / or . and see the effect. */ if((nc=walk(c, elem, 0)) == 0)
1991/0423		if(walk(&f, elem, 0) == 0)
1990/11211		error(Enonexist);
1990/0227		c = nc;
1990/11211		if(!(c->qid.path & CHDIR))
1991/0423		if(!(f.c->qid.path & CHDIR))
1990/11211		error(Enotdir);
1990/0227		break; case Aopen:
1990/0820		if(isdot) c = domount(c);
1991/0423		domount(&f);
1990/0820		else{ if((nc=walk(c, elem, mntok)) == 0)
1991/0423		if(walk(&f, elem, mntok) == 0)
1990/11211		error(Enonexist);
1990/0820		c = nc; }
1990/0227		Open:
1990/0914		saveregisters(); /* else error() in open has wrong value of c saved */
1990/0227		c = (*devtab[c->type].open)(c, omode);
1991/0423		saveregisters(); /* else error() in open has wrong value of c saved */ if(f.needcl) doclone(&f); f.c = (*devtab[f.c->type].open)(f.c, omode);
1990/08141		if(omode & OCEXEC) c->flag |= CCEXEC;
1991/0423		f.c->flag |= CCEXEC;
1990/0227		break; case Amount:
1991/0421/sys/src/9/port/chan.c:597,627 – 1991/0423/sys/src/9/port/chan.c:607,643
1990/0227		* the second mount to be attached to the original directory, not * the replacement. */ if((nc=walk(c, elem, 0)) == 0)
1991/0423		if(walk(&f, elem, 0) == 0)
1990/11211		error(Enonexist);
1990/0227		c = nc; break; case Acreate:
1990/0820		if(isdot)
1990/11211		error(Eisdir);
1990/0227		if((nc=walk(c, elem, 1)) != 0){ c = nc;
1991/0423		if(walk(&f, elem, 1) != 0){
1990/0227		omode |= OTRUNC; goto Open; } if((c->flag&(CMOUNT|CCREATE)) == CMOUNT) c = createdir(c); (*devtab[c->type].create)(c, elem, omode, perm);
1991/0423		if((f.c->flag&(CMOUNT|CCREATE)) == CMOUNT) createdir(&f); if(f.needcl) doclone(&f); (*devtab[f.c->type].create)(f.c, elem, omode, perm);
1990/08141		if(omode & OCEXEC) c->flag |= CCEXEC;
1991/0423		f.c->flag |= CCEXEC;
1990/0227		break; default: panic("unknown namec access %d\n", amode); }
1991/0423		if(f.needcl) doclone(&f);
1990/0227		poperror(); return c;
1991/0423		if(f.c->flag & CMOUNT){ f.c->mnt = f.mnt; f.c->mountid = f.mountid; } return f.c;
1990/0227		} /*
1991/0423/sys/src/9/port/chan.c:111,128 – 1991/0426/sys/src/9/port/chan.c:111,116 (short | long)
1990/0227		} void
1991/0413		freechan(Chan *c) {
1991/0414		if(decref(c) == 0){ c->flag = CFREE; lock(&chanalloc); c->next = chanalloc.free; chanalloc.free = c; unlock(&chanalloc); }
1991/0413		}                  void
1990/0227		close(Chan *c) {
1990/0907		if(c->flag & CFREE)
1991/0426/sys/src/9/port/chan.c:11,28 – 1991/0427/sys/src/9/port/chan.c:11,16 (short | long)
1990/0227		Chan *free; }chanalloc;
1991/0423		/* * used by namec, domount, and walk to point * to the current mount entry during name resolution */ typedef struct Finger Finger; struct Finger { Chan *c; /* channel we're walking */ int needcl; /* true if we need to clone c before using it */ Mount *mnt; /* last mount point we ran traversed */ ulong mountid; /* id of that mount point */ };
1990/0227		int incref(Ref *r) {
1991/0426/sys/src/9/port/chan.c:95,101 – 1991/0427/sys/src/9/port/chan.c:83,91
1990/11211		c->dev = 0;
1990/0227		c->offset = 0; c->mnt = 0;
1991/0427		c->stream = 0;
1991/0421		c->aux = 0;
1991/0427		c->mntindex = 0;
1990/0303		c->mchan = 0;
1990/11211		c->mqid = (Qid){0, 0};
1990/0227		return c;
1991/0426/sys/src/9/port/chan.c:292,304 – 1991/0427/sys/src/9/port/chan.c:282,296
1990/0227		return (*devtab[c->type].clone)(c, nc); }
1991/0423		void domount(Finger *f)
1991/0427		Chan* domount(Chan *c)
1990/0227		{ int i;
1991/0427		ulong mntid;
1990/0227		Mtab *mt;
1991/0427		Mount *mnt;
1990/0227		Pgrp *pg;
1991/0423		Chan *mc;
1991/0427		Chan *nc, *mc;
1990/0227		pg = u->p->pgrp; /*
1991/0426/sys/src/9/port/chan.c:306,317 – 1991/0427/sys/src/9/port/chan.c:298,309
1990/0227		*/ mt = pg->mtab; for(i=0; i<pg->nmtab; i++,mt++)
1991/0423		if(mt->c && eqchan(mt->c, f->c, 1))
1991/0427		if(mt->c && eqchan(mt->c, c, 1))
1990/0227		goto Found; /* * No; c is unaffected */
1991/0423		return;
1991/0427		return c;
1990/0227		/* * Yes; move c through table
1991/0426/sys/src/9/port/chan.c:318,407 – 1991/0427/sys/src/9/port/chan.c:310,408
1990/0227		*/ Found: lock(pg);
1991/0423		if(!eqchan(mt->c, f->c, 1)){ /* table changed underfoot */
1991/0427		if(!eqchan(mt->c, c, 1)){ /* table changed underfoot */
1990/0321		pprint("domount: changed underfoot?\n");
1990/0227		unlock(pg);
1991/0423		return;
1991/0427		return c;
1990/0227		}
1991/0423		f->mnt = mt->mnt; f->mountid = f->mnt->mountid; mc = mt->mnt->c;
1991/0427		mnt = mt->mnt; mntid = mnt->mountid; mc = mnt->c;
1990/0227		incref(mc); unlock(pg);
1991/0423		close(f->c); f->c = mc; f->needcl = 1;
1991/0427		if(waserror()){ close(mc); nexterror(); } nc = clone(mc, 0); close(mc); poperror(); close(c); nc->mnt = mnt; nc->mountid = mntid; return nc;
1990/0227		}
1991/0423		int walk(Finger *f, char *name, int domnt)
1991/0427		Chan* walk(Chan *ac, char *name, int domnt)
1990/0227		{
1991/0427		Mount *mnt;
1990/0227		int first = 1;
1991/0423		Mount *mnt = f->mnt; ulong mountid = f->mountid; Chan *c = f->c; Chan *mc;
1991/0427		Chan *c = ac; Chan *nc, *mc;
1990/0227		Pgrp *pg = u->p->pgrp; /* * name may be empty if the file name is "/", "#c" etc. */
1991/0423		if(name[0]){ for(;;){ if(!first || f->needcl){ mc = (*devtab[c->type].clwalk)(c, name); if(mc){ close(c); c = mc; break; } } else { if((*devtab[c->type].walk)(c, name) != 0){ break; } } if(!(c->flag&CMOUNT)) goto Notfound; if(mnt == 0) panic("walk"); /* ??? is this safe ??? */ lock(pg); if(mnt->term){ unlock(pg); goto Notfound; } if(mountid != mnt->mountid){ pprint("walk: changed underfoot? '%s'\n", name); unlock(pg); goto Notfound; } mnt = mnt->next; mountid = mnt->mountid; mc = mnt->c; incref(mc);
1991/0427		Again: if(name[0] && (*devtab[c->type].walk)(c, name)==0){ if(!(c->flag&CMOUNT)) goto Notfound; mnt = c->mnt; if(mnt == 0) panic("walk"); lock(pg); if(mnt->term){
1990/0227		unlock(pg);
1990/0914		if(!first) close(c);
1991/0423		c = mc; first = 0;
1991/0427		goto Notfound;
1990/0914		}
1991/0423		/* * we get here only if we have a cloned and walked * channel */
1991/0427		if(c->mountid != mnt->mountid){ pprint("walk: changed underfoot? '%s'\n", name); unlock(pg); goto Notfound; } mnt = mnt->next; mc = mnt->c; incref(mc); unlock(pg); if(waserror()){ close(mc); nexterror(); } if(mnt == 0) panic("walk 1"); nc = clone(mc, 0); close(mc); poperror();
1991/0423		if(!first) close(f->c); f->c = c; f->needcl = 0; f->mnt = 0;
1991/0427		close(c); nc->mnt = mnt; nc->mountid = mnt->mountid; c = nc; first = 0; goto Again; } if(name[0]) /* walk succeeded */
1991/0423		c->flag &= ~CMOUNT;
1991/0427		if(domnt){ if(waserror()){ if(!first) close(c); return 0; } c = domount(c); poperror();
1990/0914		}
1991/0423		if(domnt) domount(f);
1991/0427		if(!first) close(ac);
1990/0227
1991/0423		return 1;
1990/0914
1991/0427		return c;
1990/0227		Notfound: if(!first) close(c);
1991/0426/sys/src/9/port/chan.c:409,422 – 1991/0427/sys/src/9/port/chan.c:410,423
1990/0227		} /*
1991/0423		* f->c is a mounted non-creatable directory. find a creatable one.
1991/0427		* c is a mounted non-creatable directory. find a creatable one.
1990/0227		*/
1991/0423		void createdir(Finger *f)
1991/0427		Chan* createdir(Chan *c)
1990/0227		{ Mount *mnt; Pgrp *pg = u->p->pgrp;
1991/0423		Chan *mc;
1991/0427		Chan *mc, *nc;
1990/0227		lock(pg); if(waserror()){
1991/0426/sys/src/9/port/chan.c:423,430 – 1991/0427/sys/src/9/port/chan.c:424,431
1990/0227		unlock(pg); nexterror(); }
1991/0423		mnt = f->mnt; if(f->mountid != mnt->mountid){
1991/0427		mnt = c->mnt; if(c->mountid != mnt->mountid){
1990/0321		pprint("createdir: changed underfoot?\n");
1990/11211		error(Enocreate);
1990/0227		}
1991/0426/sys/src/9/port/chan.c:436,445 – 1991/0427/sys/src/9/port/chan.c:437,452
1990/0227		mc = mnt->c; incref(mc); unlock(pg);
1991/0427		if(waserror()){ close(mc); nexterror(); } nc = clone(mc, 0);
1990/0227		poperror();
1991/0423		close(f->c); f->needcl = 1; f->c = mc;
1991/0427		close(c); close(mc); nc->mnt = mnt; return nc;
1990/0227		}
1990/0914		void
1991/0426/sys/src/9/port/chan.c:447,465 – 1991/0427/sys/src/9/port/chan.c:454,459
1990/0914		{ }
1991/0423		void doclone(Finger *f) { Chan *nc;                  if(f->needcl == 0) return; nc = clone(f->c, 0); close(f->c); f->c = nc; f->needcl = 0; }
1990/0227		/* * Turn a name into a channel. * &name[0] is known to be a valid address. It may be a kernel address.
1991/0426/sys/src/9/port/chan.c:467,477 – 1991/0427/sys/src/9/port/chan.c:461,471
1990/0227		Chan* namec(char *name, int amode, int omode, ulong perm) {
1991/0427		Chan *c, *nc, *cc;
1990/0227		int t;
1990/0820		int mntok, isdot;
1990/0821		char *p; char *elem;
1991/0423		Finger f;
1990/0227		if(name[0] == 0)
1990/11211		error(Enonexist);
1991/0426/sys/src/9/port/chan.c:492,502 – 1991/0427/sys/src/9/port/chan.c:486,493
1990/0821		elem = u->elem;
1990/0227		mntok = 1;
1990/0820		isdot = 0;
1991/0423		f.mnt = 0;
1990/0227		if(name[0] == '/'){
1991/0423		f.c = u->slash; incref(f.c); f.needcl = 1;
1991/0427		c = clone(u->slash, 0);
1990/0227		/* * Skip leading slashes. */
1991/0426/sys/src/9/port/chan.c:514,525 – 1991/0427/sys/src/9/port/chan.c:505,513
1990/0227		elem[0]=0; }else name = nextelem(name, elem);
1991/0423		f.c = (*devtab[t].attach)(elem); f.needcl = 0;
1991/0427		c = (*devtab[t].attach)(elem);
1990/0820		}else{
1991/0423		f.c = u->dot; incref(f.c); f.needcl = 1;
1991/0427		c = clone(u->dot, 0);
1990/0820		name = skipslash(name); /* eat leading ./ */ if(*name == 0) isdot = 1;
1991/0426/sys/src/9/port/chan.c:526,532 – 1991/0427/sys/src/9/port/chan.c:514,520
1990/0820		}
1990/0227		if(waserror()){
1991/0423		close(f.c);
1991/0427		close(c);
1990/0227		nexterror(); }
1991/0426/sys/src/9/port/chan.c:537,543 – 1991/0427/sys/src/9/port/chan.c:525,531
1991/0416		* current directory. */ if(mntok && !isdot && !(amode==Amount && elem[0]==0))
1991/0423		domount(&f); /* see case Atodir below */
1991/0427		c = domount(c); /* see case Atodir below */
1990/0227		/* * How to treat the last element of the name depends on the operation.
1991/0426/sys/src/9/port/chan.c:544,551 – 1991/0427/sys/src/9/port/chan.c:532,540
1990/0227		* Therefore do all but the last element by the easy algorithm. */ while(*name){
1991/0423		if(walk(&f, elem, mntok) == 0)
1991/0427		if((nc=walk(c, elem, mntok)) == 0)
1990/11211		error(Enonexist);
1991/0427		c = nc;
1990/0227		name = nextelem(name, elem); }
1990/0820
1991/0426/sys/src/9/port/chan.c:555,564 – 1991/0427/sys/src/9/port/chan.c:544,554
1990/0227		switch(amode){ case Aaccess:
1990/0820		if(isdot)
1991/0423		domount(&f);
1991/0427		c = domount(c);
1990/0820		else{
1991/0423		if(walk(&f, elem, mntok) == 0)
1991/0427		if((nc=walk(c, elem, mntok)) == 0)
1990/11211		error(Enonexist);
1991/0427		c = nc;
1990/0820		}
1990/0227		break;
1991/0426/sys/src/9/port/chan.c:567,592 – 1991/0427/sys/src/9/port/chan.c:557,582
1990/0227		* Directories (e.g. for cd) are left before the mount point, * so one may mount on / or . and see the effect. */
1991/0423		if(walk(&f, elem, 0) == 0)
1991/0427		if((nc=walk(c, elem, 0)) == 0)
1990/11211		error(Enonexist);
1991/0423		if(!(f.c->qid.path & CHDIR))
1991/0427		c = nc; if(!(c->qid.path & CHDIR))
1990/11211		error(Enotdir);
1990/0227		break; case Aopen:
1990/0820		if(isdot)
1991/0423		domount(&f);
1991/0427		c = domount(c);
1990/0820		else{
1991/0423		if(walk(&f, elem, mntok) == 0)
1991/0427		if((nc=walk(c, elem, mntok)) == 0)
1990/11211		error(Enonexist);
1991/0427		c = nc;
1990/0820		}
1990/0227		Open:
1991/0423		saveregisters(); /* else error() in open has wrong value of c saved */ if(f.needcl) doclone(&f); f.c = (*devtab[f.c->type].open)(f.c, omode);
1991/0427		saveregisters(); /* else error() in open has wrong value of c saved */ c = (*devtab[c->type].open)(c, omode);
1990/08141		if(omode & OCEXEC)
1991/0423		f.c->flag |= CCEXEC;
1991/0427		c->flag |= CCEXEC;
1990/0227		break; case Amount:
1991/0426/sys/src/9/port/chan.c:595,631 – 1991/0427/sys/src/9/port/chan.c:585,635
1990/0227		* the second mount to be attached to the original directory, not * the replacement. */
1991/0423		if(walk(&f, elem, 0) == 0)
1991/0427		if((nc=walk(c, elem, 0)) == 0)
1990/11211		error(Enonexist);
1991/0427		c = nc;
1990/0227		break; case Acreate:
1990/0820		if(isdot)
1990/11211		error(Eisdir);
1991/0423		if(walk(&f, elem, 1) != 0){
1991/0427		/* * Walk the element before trying to create it * to see if it exists. We clone the channel * first, just in case someone is trying to * use clwalk outside the kernel. */ cc = clone(c, 0); if(waserror()){ close(cc); nexterror(); } if((nc=walk(cc, elem, 1)) != 0){ poperror(); close(c); c = nc;
1990/0227		omode |= OTRUNC; goto Open; }
1991/0423		if((f.c->flag&(CMOUNT|CCREATE)) == CMOUNT) createdir(&f); if(f.needcl) doclone(&f); (*devtab[f.c->type].create)(f.c, elem, omode, perm);
1991/0427		close(cc); poperror(); /* * the file didn't exist, try the create */ if((c->flag&(CMOUNT|CCREATE)) == CMOUNT) c = createdir(c); (*devtab[c->type].create)(c, elem, omode, perm);
1990/08141		if(omode & OCEXEC)
1991/0423		f.c->flag |= CCEXEC;
1991/0427		c->flag |= CCEXEC;
1990/0227		break; default: panic("unknown namec access %d\n", amode); }
1991/0423		if(f.needcl) doclone(&f);
1990/0227		poperror();
1991/0423		if(f.c->flag & CMOUNT){ f.c->mnt = f.mnt; f.c->mountid = f.mountid; } return f.c;
1991/0427		return c;
1990/0227		} /*
1991/0427/sys/src/9/port/chan.c:30,35 – 1991/0705/sys/src/9/port/chan.c:30,37 (short | long)
1990/0227		lock(r);
1990/1104		x = --r->ref;
1990/0227		unlock(r);
1991/0705		if(x < 0) panic("decref");
1990/1104		return x;
1990/0227		}
Too many diffs (26 > 25). Stopping.