1996/0123/port/devtinyfs.c (diff list | history)

1996/0122/sys/src/9/port/devtinyfs.c:13,20 – 1996/0123/sys/src/9/port/devtinyfs.c:13,23 (short | long | prev | next)
1996/0116		enum{ Qdir, Nfile= 32,
1996/0123		Nfile= 32,
1996/0120		Qmedium,
1996/0123		Magic= 0xfeedbeef, Superlen= 64,
1996/0116		};
1996/0122		typedef struct FS FS;
1996/0122/sys/src/9/port/devtinyfs.c:25,33 – 1996/0123/sys/src/9/port/devtinyfs.c:28,36
1996/0122		int dev; FS *next;
1996/0116		Chan *c;
1996/0122		Dirtab *file;
1996/0116		int nfile;
1996/0122		int maxfile;
1996/0123		uchar *fat; ulong nclust; ulong clustsize;
1996/0122		}; struct {
1996/0122/sys/src/9/port/devtinyfs.c:39,52 – 1996/0123/sys/src/9/port/devtinyfs.c:42,47
1996/0116		void tinyfsreset(void) { Dirtab *d;                  d = tinyfs.file; memmove(d->name, "medium"); d->qid.vers = 0;
1996/0120		d->qid.path = Qmedium;
1996/0116		d->perm = 0666;
1996/0120		tinyfs.nfile = 1;
1996/0116		} void
1996/0122/sys/src/9/port/devtinyfs.c:54,59 – 1996/0123/sys/src/9/port/devtinyfs.c:49,123
1996/0116		{ }
1996/0123		#define GETS(x) ((x)[0]|((x)[1]<<8)) #define PUTS(x, v) {(x)[0] = (v);(x)[1] = ((v)>>8);} #define GETL(x) (GETS(x)|(GETS(x+2)<<16)) #define PUTL(x, v) {PUTS(x, v);PUTS(x+2, (v)>>16)}; /* * see if we have a reasonable fat/root directory */ static int fsinit(FS *fs) { uchar buf[DIRLEN]; Dir d; ulong x; n = devtab[fs->c->type].read(fs->c, buf, Superlen, 0); if(n != Superlen) error(Eio); x = GETL(buf); if(x != Magic) return -1; fs->clustsize = GETL(buf+4); fs->nclust = GETL(buf+8); x = fs->clustsize*fs->nclust; devtab[fs->c->type].stat(fs->c, buf); convM2D(buf, &d); if(d.length < 128) error("tinyfs medium too small"); if(d.length < x) return -1; fs->fat = smalloc(2*fs->nclust); n = devtab[fs->c->type].read(fs->c, buf, 2*fs->nclust, Superlen); fd(n != 2*fs->nclust) error(Eio); x = GETS(fs->fat); if(x == 0) return -1; return 0; } /* * set up the fat and then a root directory (starting at first cluster (1)) */ static void fssetup(FS *fs) { uchar buf[DIRLEN]; Dir d; devtab[fs->c->type].stat(fs->c, buf); convM2D(buf, &d); fs->clustsize = d.length>>16; if(fs->clustsize < 64) fs->clustsize = 64; fs->nclust = (d.length - 12)/fs->clustsize; fs->fat = smalloc(2*fs->nclust); n = devtab[fs->c->type].write(fs->c, buf, 2*fs->nclust, Superlen); if(n < 2*fs->nclust) error(Eio); n = devtab[fs->c->type].write(fs->c, buf, Superlen, 0); if(n < Superlen) error(Eio); }
1996/0116		Chan * tinyfsattach(char *spec) {
1996/0122/sys/src/9/port/devtinyfs.c:61,66 – 1996/0123/sys/src/9/port/devtinyfs.c:125,135
1996/0122		Chan *c, *cc;
1996/0120
1996/0122		cc = namec((char*)arg[0], Aopen, arg[1], 0);
1996/0123		if(waserror()){ close(cc); unlock(&fs); nexterror(); }
1996/0122		qlock(&tinyfs); l = &tinyfs.l; for(fs = tinyfs.l; fs != 0; fs = fs->next){
1996/0122/sys/src/9/port/devtinyfs.c:74,84 – 1996/0123/sys/src/9/port/devtinyfs.c:143,161
1996/0122		close(cc); } else { fs = smalloc(sizeof(*fs)); *l = fs; fs->c = cc; incref(&fs->r);
1996/0123		if(waserror()){ free(fs); nexterror(); } if(fsinit(fs) < 0) fssetup(fs); poperror(); *l = fs;
1996/0122		qunlock(&tinyfs); }
1996/0123		poperror();
1996/0122		c = devattach('E', spec); c->aux = fs;
1996/0122/sys/src/9/port/devtinyfs.c:123,143 – 1996/0123/sys/src/9/port/devtinyfs.c:200,205
1996/0116		qunlock(&tinyfs); nexterror(); } qlock(&tinyfs);                  if(tinyfs.nfile == Nfile) error("out of space"); for(d = tinyfs.file; d < tinyfs.file[tinyfs.nfile]; d++) if(strcmp(name, d->name) == 0) error("create race"); strncpy(d->name, name, sizeof(d->name)-1); d->perm = perm; d->qid.vers = 0; d->qid.path = tinyfs.high++; tinyfs.nfile++;
1996/0120
1996/0116		qunlock(&tinyfs);                  c->mode = openmode(omode); c->flag |= COPEN; c->qid = d->qid;