1990/11211/port/devsrv.c (diff list | history)

1990/11211/sys/src/9/port/devsrv.c:1,287 – 1991/0318/sys/src/9/port/devsrv.c:1,287 (short | long | prev | next)
1990/0227		#include "u.h" #include "lib.h" #include "mem.h" #include "dat.h" #include "fns.h" #include "errno.h" #include "devtab.h"
1990/1002		#include "fcall.h"
1990/0227
1990/1110		void *calloc(unsigned, unsigned);
1990/1002		void free(void *); /* This structure holds the contents of a directory entry. Entries are kept * in a linked list. */
1990/1110		typedef struct Entry Entry; struct Entry {
1990/0227		Lock;
1990/1110		Entry *next; /* next entry */ Entry **back; /* entry pointer */ Entry *parent; /* parent directory */
1990/1002		Dir dir; /* dir structure */
1990/1110		union{ Chan *chan; /* if not a subdirectory */ Entry *entries; /* directory entries */
1990/1002		}; };
1990/0227		void srvinit(void) { } void srvreset(void) { }
1990/1110		Entry * srvalloc(int mode){ Entry *e;
1990/1002		static Lock qidlock; static nextqid;
1990/1110		e = calloc(1, sizeof(Entry));
1990/1002		e->dir.atime = e->dir.mtime = seconds(); lock(&qidlock); /* for qid allocation */
1990/11211		e->dir.qid = (Qid){mode|nextqid++, 0};
1990/1002		unlock(&qidlock); return e; }
1990/0227		Chan * srvattach(char *spec) {
1990/1002		Chan *c; static Lock rootlock;
1990/1110		static Entry *root;
1990/1002		lock(&rootlock);
1990/1110		if(root==0){ root = srvalloc(CHDIR);
1990/1002		root->dir.mode = CHDIR | 0777; } unlock(&rootlock); c = devattach('s', spec); c->qid = root->dir.qid; c->aux = root; return c;
1990/0227		} Chan * srvclone(Chan *c, Chan *nc) {
1990/1002		nc = devclone(c, nc); nc->aux = c->aux; return nc;
1990/0227		} int srvwalk(Chan *c, char *name) {
1990/1110		Entry *dir, *e;
1990/1002		isdir(c);
1990/1110		if(strcmp(name, ".") == 0)
1990/1002		return 1;
1990/1110		if((dir=c->aux) == 0)
1990/1002		panic("bad aux pointer in srvwalk");
1990/1110		if(strcmp(name, "..") == 0)
1990/1002		e = dir->parent;
1990/1110		else{
1990/1002		lock(dir);
1990/1110		for(e=dir->entries; e; e=e->next)
1990/1002		if (strcmp(name, e->dir.name) == 0) break; unlock(dir); }
1990/1110		if(e==0){
1990/11211		strncpy(u->error, errstrtab[Enonexist], NAMELEN);
1990/1002		return 0; } c->qid = e->dir.qid; c->aux = e; return 1;
1990/0227		} void srvstat(Chan *c, char *db) {
1990/1110		Entry *e;
1990/1002
1990/1110		e = c->aux;
1990/1002		convD2M(&e->dir, db);
1990/0227		} Chan * srvopen(Chan *c, int omode) {
1990/1110		Entry *e;
1990/0227		Chan *f;
1990/11211		if(c->qid.path & CHDIR){
1990/1110		if(omode != OREAD)
1990/11211		error(Eisdir);
1990/0227		c->mode = omode; c->flag |= COPEN; c->offset = 0; return c; }
1990/1110		if((e=c->aux) == 0)
1990/11211		error(Egreg);
1990/1110		if((f=e->chan) == 0)
1990/11211		error(Eshutdown);
1990/1110		if(omode & OTRUNC)
1990/11211		error(Eperm);
1990/1110		if(omode!=f->mode && f->mode!=ORDWR)
1990/11211		error(Eperm);
1990/0227		close(c); incref(f); return f; } void srvcreate(Chan *c, char *name, int omode, ulong perm) {
1990/1110		Entry *parent, *e;
1990/0227
1990/1110		parent = c->aux;
1990/1002		isdir(c); lock(parent);
1990/1110		if (waserror()){
1990/1002		unlock(parent);
1990/0227		nexterror(); }
1990/1110		for(e=parent->entries; e; e=e->next) if(strcmp(name, e->dir.name) == 0)
1990/11211		error(Einuse);
1990/1110		e = srvalloc(perm & CHDIR);
1990/1002		e->parent = parent; strcpy(e->dir.name, name); e->dir.mode = perm & parent->dir.mode;
1990/11211		strcpy(e->dir.gid, parent->dir.gid);
1990/1110		if(e->next = parent->entries) /* assign = */
1990/1002		e->next->back = &e->next;
1990/1110		e->back = &parent->entries; *e->back = e;
1990/1002		parent->dir.mtime = e->dir.mtime; unlock(parent); poperror();
1990/1121		c->qid = e->dir.qid;
1990/1002		c->aux = e;
1990/0227		c->flag |= COPEN;
1990/1002		c->mode = omode;
1990/0227		} void srvremove(Chan *c) {
1990/1110		Entry *e;
1990/0227
1990/1110		e = c->aux; if(e->parent == 0)
1990/11211		error(Eperm);
1990/1002		lock(e->parent);
1990/1110		if(waserror()){
1990/1002		unlock(e->parent);
1990/0227		nexterror(); }
1990/1110		if(e->dir.mode & CHDIR){
1990/1002		if (e->entries != 0)
1990/11211		error(Eperm);
1990/1110		}else{ if(e->chan == 0)
1990/11211		error(Eshutdown);
1990/1002		close(e->chan); }
1990/1110		if(*e->back = e->next) /* assign = */
1990/1002		e->next->back = e->back; unlock(e->parent);
1990/0227		poperror();
1990/1002		free(e);
1990/0227		} void srvwstat(Chan *c, char *dp) {
1990/11211		error(Egreg);
1990/0227		} void srvclose(Chan *c) { }
1990/1002		/* A directory is being read. The entries must be synthesized. e points * to a list of entries in this directory. Count is the size to be * read. */
1990/1110		int srvdirentry(Entry *e, char *a, long count){
1990/1002		Dir dir;
1990/1110		int n;
1990/1002
1990/1110		n = 0; while(n!=count && e!=0){
1990/1002		n += convD2M(&e->dir, a + n); e = e->next; } return n; }
1990/0227		long srvread(Chan *c, void *va, long n) {
1990/1110		Entry *dir, *e; int offset;
1990/0227
1990/1110		dir = c->aux; offset = c->offset;
1990/1002		isdir(c);
1990/1110		if(n <= 0)
1990/1002		return 0;
1990/1110		if(offset%DIRLEN || n%DIRLEN)
1990/11211		error(Ebaddirread);
1990/1002		lock(dir);
1990/1110		for(e=dir->entries; e; e=e->next) if(offset <= 0){ n = srvdirentry(e, va, n);
1990/1002		unlock(dir); c->offset += n; return n;
1990/1110		}else
1990/1002		offset -= DIRLEN; unlock(dir); return 0;
1990/0227		} long srvwrite(Chan *c, void *va, long n) {
1990/1110		Entry *e;
1990/0227		int i, fd; char buf[32];
1990/1110		e = c->aux; if(e->dir.mode & CHDIR)
1990/1002		panic("write to directory"); lock(e);
1990/1110		if(waserror()){
1990/1002		unlock(e); nexterror(); }
1990/1110		if(e->chan)
1990/11211		error(Egreg);
1990/1110		if(n >= sizeof buf)
1990/11211		error(Egreg);
1990/0227		memcpy(buf, va, n); /* so we can NUL-terminate */
1991/0318		memmove(buf, va, n); /* so we can NUL-terminate */
1990/0227		buf[n] = 0; fd = strtoul(buf, 0, 0); fdtochan(fd, -1); /* error check only */
1990/1002		e->chan = u->fd[fd]; incref(e->chan); unlock(e); poperror();
1990/0227		return n; }