1 64f7506b 2006-02-24 devnull /*
  2 64f7506b 2006-02-24 devnull  * 10th edition 4K file system
  3 64f7506b 2006-02-24 devnull  */
  4 64f7506b 2006-02-24 devnull #include <u.h>
  5 64f7506b 2006-02-24 devnull #include <libc.h>
  6 64f7506b 2006-02-24 devnull #include <auth.h>
  7 64f7506b 2006-02-24 devnull #include <fcall.h>
  8 64f7506b 2006-02-24 devnull #include "tapefs.h"
  9 64f7506b 2006-02-24 devnull 
 10 64f7506b 2006-02-24 devnull /*
 11 64f7506b 2006-02-24 devnull  * v10 disk inode
 12 64f7506b 2006-02-24 devnull  */
 13 64f7506b 2006-02-24 devnull #define	VNADDR	13
 14 64f7506b 2006-02-24 devnull #define	VFMT	0160000
 15 64f7506b 2006-02-24 devnull #define	VIFREG	0100000
 16 64f7506b 2006-02-24 devnull #define	VIFDIR	0040000
 17 64f7506b 2006-02-24 devnull #define	VIFCHR	0120000
 18 64f7506b 2006-02-24 devnull #define	VIFBLK	0160000
 19 64f7506b 2006-02-24 devnull #define	VMODE	0777
 20 64f7506b 2006-02-24 devnull #define	VSUPERB	1
 21 64f7506b 2006-02-24 devnull #define	VROOT		2	/* root inode */
 22 64f7506b 2006-02-24 devnull #define	VNAMELEN	14
 23 64f7506b 2006-02-24 devnull #define	BLSIZE	4096
 24 64f7506b 2006-02-24 devnull #define	LINOPB	(BLSIZE/sizeof(struct v10dinode))
 25 64f7506b 2006-02-24 devnull #define	LNINDIR	(BLSIZE/sizeof(unsigned long))
 26 64f7506b 2006-02-24 devnull 
 27 64f7506b 2006-02-24 devnull struct v10dinode {
 28 64f7506b 2006-02-24 devnull 	unsigned char flags[2];
 29 64f7506b 2006-02-24 devnull 	unsigned char nlinks[2];
 30 64f7506b 2006-02-24 devnull 	unsigned char uid[2];
 31 64f7506b 2006-02-24 devnull 	unsigned char gid[2];
 32 64f7506b 2006-02-24 devnull 	unsigned char size[4];
 33 64f7506b 2006-02-24 devnull 	unsigned char addr[40];
 34 64f7506b 2006-02-24 devnull 	unsigned char atime[4];
 35 64f7506b 2006-02-24 devnull 	unsigned char mtime[4];
 36 64f7506b 2006-02-24 devnull 	unsigned char ctime[4];
 37 64f7506b 2006-02-24 devnull };
 38 64f7506b 2006-02-24 devnull 
 39 64f7506b 2006-02-24 devnull struct	v10dir {
 40 64f7506b 2006-02-24 devnull 	uchar	ino[2];
 41 64f7506b 2006-02-24 devnull 	char	name[VNAMELEN];
 42 64f7506b 2006-02-24 devnull };
 43 64f7506b 2006-02-24 devnull 
 44 64f7506b 2006-02-24 devnull int	tapefile;
 45 64f7506b 2006-02-24 devnull Fileinf	iget(int ino);
 46 64f7506b 2006-02-24 devnull long	bmap(Ram *r, long bno);
 47 64f7506b 2006-02-24 devnull void	getblk(Ram *r, long bno, char *buf);
 48 64f7506b 2006-02-24 devnull 
 49 64f7506b 2006-02-24 devnull void
 50 64f7506b 2006-02-24 devnull populate(char *name)
 51 64f7506b 2006-02-24 devnull {
 52 64f7506b 2006-02-24 devnull 	Fileinf f;
 53 64f7506b 2006-02-24 devnull 
 54 64f7506b 2006-02-24 devnull 	replete = 0;
 55 64f7506b 2006-02-24 devnull 	tapefile = open(name, OREAD);
 56 64f7506b 2006-02-24 devnull 	if (tapefile<0)
 57 64f7506b 2006-02-24 devnull 		error("Can't open argument file");
 58 64f7506b 2006-02-24 devnull 	f = iget(VROOT);
 59 64f7506b 2006-02-24 devnull 	ram->perm = f.mode;
 60 64f7506b 2006-02-24 devnull 	ram->mtime = f.mdate;
 61 64f7506b 2006-02-24 devnull 	ram->addr = f.addr;
 62 64f7506b 2006-02-24 devnull 	ram->data = f.data;
 63 64f7506b 2006-02-24 devnull 	ram->ndata = f.size;
 64 64f7506b 2006-02-24 devnull }
 65 64f7506b 2006-02-24 devnull 
 66 64f7506b 2006-02-24 devnull void
 67 64f7506b 2006-02-24 devnull popdir(Ram *r)
 68 64f7506b 2006-02-24 devnull {
 69 64f7506b 2006-02-24 devnull 	int i, ino;
 70 64f7506b 2006-02-24 devnull 	char *cp;
 71 64f7506b 2006-02-24 devnull 	struct v10dir *dp;
 72 64f7506b 2006-02-24 devnull 	Fileinf f;
 73 64f7506b 2006-02-24 devnull 	char name[VNAMELEN+1];
 74 64f7506b 2006-02-24 devnull 
 75 64f7506b 2006-02-24 devnull 	cp = 0;
 76 64f7506b 2006-02-24 devnull 	for (i=0; i<r->ndata; i+=sizeof(struct v10dir)) {
 77 64f7506b 2006-02-24 devnull 		if (i%BLSIZE==0)
 78 64f7506b 2006-02-24 devnull 			cp = doread(r, i, BLSIZE);
 79 64f7506b 2006-02-24 devnull 		dp = (struct v10dir *)(cp+i%BLSIZE);
 80 64f7506b 2006-02-24 devnull 		ino = g2byte(dp->ino);
 81 64f7506b 2006-02-24 devnull 		if (strcmp(dp->name, ".")==0 || strcmp(dp->name, "..")==0)
 82 64f7506b 2006-02-24 devnull 			continue;
 83 64f7506b 2006-02-24 devnull 		if (ino==0)
 84 64f7506b 2006-02-24 devnull 			continue;
 85 64f7506b 2006-02-24 devnull 		f = iget(ino);
 86 64f7506b 2006-02-24 devnull 		strncpy(name, dp->name, VNAMELEN);
 87 ada24b40 2008-05-10 rsc 		name[VNAMELEN] = '\0';
 88 64f7506b 2006-02-24 devnull 		f.name = name;
 89 64f7506b 2006-02-24 devnull 		popfile(r, f);
 90 64f7506b 2006-02-24 devnull 	}
 91 64f7506b 2006-02-24 devnull 	r->replete = 1;
 92 64f7506b 2006-02-24 devnull }
 93 64f7506b 2006-02-24 devnull 
 94 64f7506b 2006-02-24 devnull void
 95 64f7506b 2006-02-24 devnull dotrunc(Ram *r)
 96 64f7506b 2006-02-24 devnull {
 97 64f7506b 2006-02-24 devnull 	USED(r);
 98 64f7506b 2006-02-24 devnull }
 99 64f7506b 2006-02-24 devnull 
100 64f7506b 2006-02-24 devnull void
101 64f7506b 2006-02-24 devnull docreate(Ram *r)
102 64f7506b 2006-02-24 devnull {
103 64f7506b 2006-02-24 devnull 	USED(r);
104 64f7506b 2006-02-24 devnull }
105 64f7506b 2006-02-24 devnull 
106 64f7506b 2006-02-24 devnull char *
107 64f7506b 2006-02-24 devnull doread(Ram *r, vlong off, long cnt)
108 64f7506b 2006-02-24 devnull {
109 64f7506b 2006-02-24 devnull 	static char buf[Maxbuf+BLSIZE];
110 64f7506b 2006-02-24 devnull 	int bno, i;
111 64f7506b 2006-02-24 devnull 
112 64f7506b 2006-02-24 devnull 	bno = off/BLSIZE;
113 64f7506b 2006-02-24 devnull 	off -= bno*BLSIZE;
114 64f7506b 2006-02-24 devnull 	if (cnt>Maxbuf)
115 64f7506b 2006-02-24 devnull 		error("count too large");
116 64f7506b 2006-02-24 devnull 	if (off)
117 64f7506b 2006-02-24 devnull 		cnt += off;
118 64f7506b 2006-02-24 devnull 	i = 0;
119 64f7506b 2006-02-24 devnull 	while (cnt>0) {
120 64f7506b 2006-02-24 devnull 		getblk(r, bno, &buf[i*BLSIZE]);
121 64f7506b 2006-02-24 devnull 		cnt -= BLSIZE;
122 64f7506b 2006-02-24 devnull 		bno++;
123 64f7506b 2006-02-24 devnull 		i++;
124 64f7506b 2006-02-24 devnull 	}
125 64f7506b 2006-02-24 devnull 	return buf+off;
126 64f7506b 2006-02-24 devnull }
127 64f7506b 2006-02-24 devnull 
128 64f7506b 2006-02-24 devnull void
129 64f7506b 2006-02-24 devnull dowrite(Ram *r, char *buf, long off, long cnt)
130 64f7506b 2006-02-24 devnull {
131 64f7506b 2006-02-24 devnull 	USED(r); USED(buf); USED(off); USED(cnt);
132 64f7506b 2006-02-24 devnull }
133 64f7506b 2006-02-24 devnull 
134 64f7506b 2006-02-24 devnull int
135 64f7506b 2006-02-24 devnull dopermw(Ram *r)
136 64f7506b 2006-02-24 devnull {
137 64f7506b 2006-02-24 devnull 	USED(r);
138 64f7506b 2006-02-24 devnull 	return 0;
139 64f7506b 2006-02-24 devnull }
140 64f7506b 2006-02-24 devnull 
141 64f7506b 2006-02-24 devnull /*
142 64f7506b 2006-02-24 devnull  * fetch an i-node
143 64f7506b 2006-02-24 devnull  * -- no sanity check for now
144 64f7506b 2006-02-24 devnull  * -- magic inode-to-disk-block stuff here
145 64f7506b 2006-02-24 devnull  */
146 64f7506b 2006-02-24 devnull 
147 64f7506b 2006-02-24 devnull Fileinf
148 64f7506b 2006-02-24 devnull iget(int ino)
149 64f7506b 2006-02-24 devnull {
150 64f7506b 2006-02-24 devnull 	char buf[BLSIZE];
151 64f7506b 2006-02-24 devnull 	struct v10dinode *dp;
152 64f7506b 2006-02-24 devnull 	long flags, i;
153 64f7506b 2006-02-24 devnull 	Fileinf f;
154 64f7506b 2006-02-24 devnull 
155 71e936d7 2006-04-20 devnull 	memset(&f, 0, sizeof f);
156 64f7506b 2006-02-24 devnull 	seek(tapefile, BLSIZE*((ino-1)/LINOPB + VSUPERB + 1), 0);
157 64f7506b 2006-02-24 devnull 	if (read(tapefile, buf, BLSIZE) != BLSIZE)
158 64f7506b 2006-02-24 devnull 		error("Can't read inode");
159 64f7506b 2006-02-24 devnull 	dp = ((struct v10dinode *)buf) + ((ino-1)%LINOPB);
160 64f7506b 2006-02-24 devnull 	flags = g2byte(dp->flags);
161 64f7506b 2006-02-24 devnull 	f.size = g4byte(dp->size);
162 64f7506b 2006-02-24 devnull 	if ((flags&VFMT)==VIFCHR || (flags&VFMT)==VIFBLK)
163 64f7506b 2006-02-24 devnull 		f.size = 0;
164 64f7506b 2006-02-24 devnull 	f.data = emalloc(VNADDR*sizeof(long));
165 64f7506b 2006-02-24 devnull 	for (i = 0; i < VNADDR; i++)
166 64f7506b 2006-02-24 devnull 		((long*)f.data)[i] = g3byte(dp->addr+3*i);
167 64f7506b 2006-02-24 devnull 	f.mode = flags & VMODE;
168 64f7506b 2006-02-24 devnull 	if ((flags&VFMT)==VIFDIR)
169 64f7506b 2006-02-24 devnull 		f.mode |= DMDIR;
170 64f7506b 2006-02-24 devnull 	f.uid = g2byte(dp->uid);
171 fa325e9b 2020-01-10 cross 	f.gid = g2byte(dp->gid);
172 64f7506b 2006-02-24 devnull 	f.mdate = g4byte(dp->mtime);
173 64f7506b 2006-02-24 devnull 	return f;
174 64f7506b 2006-02-24 devnull }
175 64f7506b 2006-02-24 devnull 
176 64f7506b 2006-02-24 devnull void
177 64f7506b 2006-02-24 devnull getblk(Ram *r, long bno, char *buf)
178 64f7506b 2006-02-24 devnull {
179 64f7506b 2006-02-24 devnull 	long dbno;
180 64f7506b 2006-02-24 devnull 
181 64f7506b 2006-02-24 devnull 	if ((dbno = bmap(r, bno)) == 0) {
182 64f7506b 2006-02-24 devnull 		memset(buf, 0, BLSIZE);
183 64f7506b 2006-02-24 devnull 		return;
184 64f7506b 2006-02-24 devnull 	}
185 64f7506b 2006-02-24 devnull 	seek(tapefile, dbno*BLSIZE, 0);
186 64f7506b 2006-02-24 devnull 	if (read(tapefile, buf, BLSIZE) != BLSIZE)
187 64f7506b 2006-02-24 devnull 		error("bad read");
188 64f7506b 2006-02-24 devnull }
189 64f7506b 2006-02-24 devnull 
190 64f7506b 2006-02-24 devnull /*
191 64f7506b 2006-02-24 devnull  * logical to physical block
192 64f7506b 2006-02-24 devnull  * only singly-indirect files for now
193 64f7506b 2006-02-24 devnull  */
194 64f7506b 2006-02-24 devnull 
195 64f7506b 2006-02-24 devnull long
196 64f7506b 2006-02-24 devnull bmap(Ram *r, long bno)
197 64f7506b 2006-02-24 devnull {
198 64f7506b 2006-02-24 devnull 	unsigned char indbuf[LNINDIR][sizeof(long)];
199 64f7506b 2006-02-24 devnull 
200 64f7506b 2006-02-24 devnull 	if (bno < VNADDR-3)
201 64f7506b 2006-02-24 devnull 		return ((long*)r->data)[bno];
202 64f7506b 2006-02-24 devnull 	if (bno < VNADDR*LNINDIR) {
203 64f7506b 2006-02-24 devnull 		seek(tapefile, ((long *)r->data)[(bno-(VNADDR-3))/LNINDIR+(VNADDR-3)]*BLSIZE, 0);
204 64f7506b 2006-02-24 devnull 		if (read(tapefile, (char *)indbuf, BLSIZE) != BLSIZE)
205 64f7506b 2006-02-24 devnull 			return 0;
206 64f7506b 2006-02-24 devnull 		return ((indbuf[(bno-(VNADDR-3))%LNINDIR][2]<<16) + (indbuf[(bno-(VNADDR-3))%LNINDIR][1]<<8)
207 64f7506b 2006-02-24 devnull 			+ indbuf[(bno-(VNADDR-3))%LNINDIR][0]);
208 64f7506b 2006-02-24 devnull 	}
209 64f7506b 2006-02-24 devnull 	return 0;
210 64f7506b 2006-02-24 devnull }