1999/0629/port/chan.c (diff list | history)

1999/0501/sys/src/9/port/chan.c:5,10 – 1999/0629/sys/src/9/port/chan.c:5,15 (short | long | prev | next)
1990/0227		#include "fns.h"
1992/0111		#include "../port/error.h"
1990/0227
1999/0629		enum { CNAMESLOP = 20 };
1992/0620		struct {
1990/0227		Lock;
1999/0501/sys/src/9/port/chan.c:13,18 – 1999/0629/sys/src/9/port/chan.c:18,25
1993/0501		Chan *list;
1990/0227		}chanalloc;
1999/0629		#define SEP(c) ((c) == 0 || (c) == '/')
1990/0227		int incref(Ref *r) {
1999/0501/sys/src/9/port/chan.c:100,112 – 1999/0629/sys/src/9/port/chan.c:107,179
1998/0829		c->uri = 0;
1992/0620		c->aux = 0; c->mchan = 0;
1993/0501		c->path = 0;
1993/1013		c->mcp = 0;
1992/0620		c->mqid = (Qid){0, 0};
1999/0629		c->name = 0;
1992/0620		return c;
1990/0227		}
1999/0629		static Ref ncname; Cname* newcname(char *s) { Cname *n; int i; n = smalloc(sizeof(Cname)); i = strlen(s); n->len = i; n->alen = i+CNAMESLOP; n->s = smalloc(n->alen); memmove(n->s, s, i+1); n->ref = 1; incref(&ncname); return n; }
1997/1210		void
1999/0629		cnameclose(Cname *n) { if(n == 0) return; if(decref(n)) return; decref(&ncname); free(n->s); free(n); } Cname* addelem(Cname *n, char *s) { int i, a; char *t; Cname *new; if(n->ref > 1){ /* copy on write */ new = newcname(n->s); cnameclose(n); n = new; } i = strlen(s); if(n->len+1+i+1 < n->alen){ a = n->len+1+i+1 + CNAMESLOP; t = smalloc(a); memmove(t, n->s, n->len+1); free(n->s); n->s = t; n->alen = a; } n->s[n->len++] = '/'; memmove(n->s+n->len, s, i+1); n->len += i; return n; } void
1992/0320		chanfree(Chan *c) { c->flag = CFREE;
1999/0501/sys/src/9/port/chan.c:121,138 – 1999/0629/sys/src/9/port/chan.c:188,194
1998/0829		c->mh = nil; }
1993/0501		/* * Channel can be closed before a path is created or the last * channel in a mount which has already cleared its pt names */
1998/0416		if(c->path) { if (c->path->ref <= 0) {
1998/0512		char buf[100]; ptpath(c->path, buf, sizeof(buf)); print("decref %s\n", buf); }
1993/0501		decref(c->path);
1998/0512		}
1999/0629		cnameclose(c->name);
1993/0501
1992/0320		lock(&chanalloc); c->next = chanalloc.free;
1999/0501/sys/src/9/port/chan.c:333,339 – 1999/0629/sys/src/9/port/chan.c:389,401
1990/0227		Chan*
1997/0327		cclone(Chan *c, Chan *nc)
1990/0227		{
1997/0327		return devtab[c->type]->clone(c, nc);
1999/0629		nc = devtab[c->type]->clone(c, nc); if(nc != nil){ nc->name = c->name; if(c->name) incref(c->name); } return nc;
1990/0227		}
1991/0427		Chan*
1999/0501/sys/src/9/port/chan.c:411,416 – 1999/0629/sys/src/9/port/chan.c:473,493
1991/1011		}
1990/0914
1998/0224		int
1999/0629		walkname(Chan **cp, char *name, int domnt) { Chan *c; if(walk(cp, name, domnt) < 0) return -1; c = *cp; if(c->name == nil) c->name = newcname(name); else c->name = addelem(c->name, name); return 0; } int
1998/0224		walk(Chan **cp, char *name, int domnt)
1991/1011		{
1998/0224		Chan *c, *ac;
1999/0501/sys/src/9/port/chan.c:563,568 – 1999/0629/sys/src/9/port/chan.c:640,695
1990/0914		}
1990/0227		/*
1999/0629		* In place, rewrite name to compress multiple /, eliminate ., and process .. */ void cleanname(Cname *n, int offset) { char *p, *q, *dotdot, *name; int rooted; name = n->s+offset; rooted = name[0] == '/'; /* * invariants: * p points at beginning of path element we're considering. * q points just past the last path element we wrote (no slash). * dotdot points just past the point where .. cannot backtrack * any further (no slash). */ p = q = dotdot = name+rooted; while(*p) { if(p[0] == '/') /* null element */ p++; else if(p[0] == '.' && SEP(p[1])) p += 1; /* don't count the separator in case it is nul */ else if(p[0] == '.' && p[1] == '.' && SEP(p[2])) { p += 2; if(q > dotdot) { /* can backtrack */ while(--q > dotdot && *q != '/') ; } else if(!rooted) { /* ``/..'' ≡ ``/'', but ``./../'' ≡ ``..'' */ if(q != name) *q++ = '/'; *q++ = '.'; *q++ = '.'; dotdot = q; } } else { /* real path element */ if(q != name+rooted) *q++ = '/'; while((*q = *p) != '/' && *q != 0) p++, q++; } } if(q == name) /* empty string is really ``.'' */ *q++ = '.'; *q = 0; n->len = (q-name) + offset; } /*
1990/0227		* Turn a name into a channel. * &name[0] is known to be a valid address. It may be a kernel address. */
1999/0501/sys/src/9/port/chan.c:572,578 – 1999/0629/sys/src/9/port/chan.c:699,706
1992/1217		Rune r;
1990/0821		char *p;
1992/0711		char *elem;
1993/0501		int t, n;
1999/0629		Cname *cname; int t, n, newname;
1993/0501		int mntok, isdot;
1998/0224		Chan *c, *cc;
1991/1105		char createerr[ERRLEN];
1999/0501/sys/src/9/port/chan.c:589,603 – 1999/0629/sys/src/9/port/chan.c:717,740
1990/0821		} }
1999/0629		newname = 1; cname = nil; if(waserror()){ cnameclose(cname); nexterror(); }
1993/0501		elem = up->elem;
1990/0227		mntok = 1;
1990/0820		isdot = 0;
1993/0501		switch(name[0]) { case '/':
1997/0327		c = cclone(up->slash, 0);
1999/0629		cname = newcname(name); /* save this before advancing */
1990/0227		name = skipslash(name);
1999/0629		c = cclone(up->slash, 0);
1993/0501		break; case '#':
1999/0629		cname = newcname(name); /* save this before advancing */
1990/0227		mntok = 0;
1993/0501		elem[0] = 0; n = 0;
1999/0501/sys/src/9/port/chan.c:611,616 – 1999/0629/sys/src/9/port/chan.c:748,755
1995/0208		name = skipslash(name); if(*name) error(Efilename);
1999/0629		poperror(); cnameclose(cname);
1995/0208		return c; } else {
1999/0501/sys/src/9/port/chan.c:627,632 – 1999/0629/sys/src/9/port/chan.c:766,773
1993/0501		name = skipslash(name); break; default:
1999/0629		cname = newcname(up->dot->name->s); cname = addelem(cname, name);
1997/0327		c = cclone(up->dot, 0);
1993/0501		name = skipslash(name);
1990/0820		if(*name == 0)
1999/0501/sys/src/9/port/chan.c:688,694 – 1999/0629/sys/src/9/port/chan.c:829,838
1993/1017		if(omode == OEXEC)
1993/1018		c->flag &= ~CCACHE;
1998/0512
1999/0629		cc = c;
1999/0122		c = devtab[c->type]->open(c, omode&~OCEXEC);
1999/0629		if(cc != c) newname = 0;
1993/1018
1990/08141		if(omode & OCEXEC)
1991/0427		c->flag |= CCEXEC;
1999/0501/sys/src/9/port/chan.c:760,765 – 1999/0629/sys/src/9/port/chan.c:904,923
1990/0227		default: panic("unknown namec access %d\n", amode); }
1999/0629		poperror(); /* peculiar workaround for #/ */ if(newname){ if(cname->s[0]=='#' && cname->s[1]=='/') cleanname(cname, 2); else cleanname(cname, 0); cnameclose(c->name); c->name = cname; }else cnameclose(cname);
1990/0227		poperror();
1991/0427		return c;
1990/0227		}