1 7285a491 2004-06-17 devnull #include <u.h>
  2 7285a491 2004-06-17 devnull #include <libc.h>
  3 7285a491 2004-06-17 devnull #include <bio.h>
  4 7285a491 2004-06-17 devnull #include <libsec.h>
  5 7285a491 2004-06-17 devnull 
  6 7285a491 2004-06-17 devnull #include "iso9660.h"
  7 7285a491 2004-06-17 devnull 
  8 7285a491 2004-06-17 devnull /*
  9 7285a491 2004-06-17 devnull  * Add the requisite path tables to the CD image.
 10 7285a491 2004-06-17 devnull  * They get put on the end once everything else is done.
 11 7285a491 2004-06-17 devnull  * We use the path table itself as a queue in the breadth-first
 12 fa325e9b 2020-01-10 cross  * traversal of the tree.
 13 7285a491 2004-06-17 devnull  *
 14 7285a491 2004-06-17 devnull  * The only problem with this is that the path table does not
 15 7285a491 2004-06-17 devnull  * store the lengths of the directories.  So we keep an explicit
 16 7285a491 2004-06-17 devnull  * map in an array in memory.
 17 7285a491 2004-06-17 devnull  */
 18 7285a491 2004-06-17 devnull 
 19 7285a491 2004-06-17 devnull enum {
 20 7285a491 2004-06-17 devnull 	Big,
 21 7285a491 2004-06-17 devnull 	Little
 22 7285a491 2004-06-17 devnull };
 23 7285a491 2004-06-17 devnull 
 24 7285a491 2004-06-17 devnull static void
 25 7285a491 2004-06-17 devnull Crdpath(Cdimg *cd, Cpath *p)
 26 7285a491 2004-06-17 devnull {
 27 7285a491 2004-06-17 devnull 	p->namelen = Cgetc(cd);
 28 7285a491 2004-06-17 devnull 	if(p->namelen == 0) {
 29 7285a491 2004-06-17 devnull 		Crseek(cd, (Croffset(cd)+Blocksize-1)/Blocksize * Blocksize);
 30 7285a491 2004-06-17 devnull 		p->namelen = Cgetc(cd);
 31 7285a491 2004-06-17 devnull 		assert(p->namelen != 0);
 32 7285a491 2004-06-17 devnull 	}
 33 7285a491 2004-06-17 devnull 
 34 7285a491 2004-06-17 devnull 	p->xlen = Cgetc(cd);
 35 7285a491 2004-06-17 devnull 	assert(p->xlen == 0);	/* sanity, might not be true if we start using the extended fields */
 36 7285a491 2004-06-17 devnull 
 37 7285a491 2004-06-17 devnull 	Cread(cd, p->dloc, 4);
 38 7285a491 2004-06-17 devnull 	Cread(cd, p->parent, 2);
 39 7285a491 2004-06-17 devnull 	p->name[0] = '\0';
 40 7285a491 2004-06-17 devnull 	Crseek(cd, Croffset(cd)+p->namelen+p->xlen+(p->namelen&1));	/* skip name, ext data */
 41 7285a491 2004-06-17 devnull }
 42 7285a491 2004-06-17 devnull 
 43 7285a491 2004-06-17 devnull static void
 44 7285a491 2004-06-17 devnull writepath(Cdimg *cd, Cdir *c, int parent, int size)
 45 7285a491 2004-06-17 devnull {
 46 7285a491 2004-06-17 devnull /*
 47 7285a491 2004-06-17 devnull 	DO NOT UNCOMMENT THIS CODE.
 48 7285a491 2004-06-17 devnull 	This commented-out code is here only so that no one comes
 49 7285a491 2004-06-17 devnull 	along and adds it later.
 50 7285a491 2004-06-17 devnull 
 51 7285a491 2004-06-17 devnull 	The ISO 9660 spec is silent about whether path table entries
 52 7285a491 2004-06-17 devnull 	need to be padded so that they never cross block boundaries.
 53 7285a491 2004-06-17 devnull 	It would be reasonable to assume that they are like every other
 54 7285a491 2004-06-17 devnull 	data structure in the bloody spec; this code pads them out.
 55 7285a491 2004-06-17 devnull 
 56 7285a491 2004-06-17 devnull 	Empirically, though, they're NOT padded.  Windows NT and
 57 7285a491 2004-06-17 devnull 	derivatives are the only known current operating systems
 58 7285a491 2004-06-17 devnull 	that actually read these things.
 59 7285a491 2004-06-17 devnull 
 60 7285a491 2004-06-17 devnull 	int l;
 61 7285a491 2004-06-17 devnull 
 62 7285a491 2004-06-17 devnull 	l = 1+1+4+2+c->namelen;
 63 7285a491 2004-06-17 devnull 	if(Cwoffset(cd)/Blocksize != (Cwoffset(cd)+l)/Blocksize)
 64 7285a491 2004-06-17 devnull 		Cpadblock(cd);
 65 7285a491 2004-06-17 devnull */
 66 7285a491 2004-06-17 devnull 	Cputc(cd, c->namelen);
 67 7285a491 2004-06-17 devnull 	Cputc(cd, 0);
 68 7285a491 2004-06-17 devnull 	Cwrite(cd, c->dloc + (size==Little ? 0 : 4), 4);
 69 7285a491 2004-06-17 devnull 	(size==Little ? Cputnl : Cputnm)(cd, parent, 2);
 70 7285a491 2004-06-17 devnull 	Cwrite(cd, c->name, c->namelen);
 71 7285a491 2004-06-17 devnull 	if(c->namelen & 1)
 72 7285a491 2004-06-17 devnull 		Cputc(cd, 0);
 73 7285a491 2004-06-17 devnull }
 74 7285a491 2004-06-17 devnull 
 75 7285a491 2004-06-17 devnull static ulong*
 76 7285a491 2004-06-17 devnull addlength(ulong *a, ulong x, int n)
 77 7285a491 2004-06-17 devnull {
 78 7285a491 2004-06-17 devnull 	if(n%128==0)
 79 7285a491 2004-06-17 devnull 		a = erealloc(a, (n+128)*sizeof a[0]);
 80 7285a491 2004-06-17 devnull 	a[n] = x;
 81 7285a491 2004-06-17 devnull 	return a;
 82 7285a491 2004-06-17 devnull }
 83 7285a491 2004-06-17 devnull 
 84 7285a491 2004-06-17 devnull static ulong
 85 7285a491 2004-06-17 devnull writepathtable(Cdimg *cd, ulong vdblock, int size)
 86 7285a491 2004-06-17 devnull {
 87 7285a491 2004-06-17 devnull 	int rp, wp;
 88 7285a491 2004-06-17 devnull 	uchar buf[Blocksize];
 89 7285a491 2004-06-17 devnull 	ulong bk, end, i, *len, n, rdoff, start;
 90 7285a491 2004-06-17 devnull 	Cdir *c;
 91 7285a491 2004-06-17 devnull 	Cpath p;
 92 7285a491 2004-06-17 devnull 
 93 7285a491 2004-06-17 devnull 	Creadblock(cd, buf, vdblock, Blocksize);
 94 7285a491 2004-06-17 devnull 	c = (Cdir*)(buf+offsetof(Cvoldesc, rootdir[0]));
 95 7285a491 2004-06-17 devnull 
 96 7285a491 2004-06-17 devnull 	rp = 0;
 97 7285a491 2004-06-17 devnull 	wp = 0;
 98 7285a491 2004-06-17 devnull 	len = nil;
 99 7285a491 2004-06-17 devnull 	start = cd->nextblock*Blocksize;
100 7285a491 2004-06-17 devnull 	Cwseek(cd, start);
101 7285a491 2004-06-17 devnull 	Crseek(cd, start);
102 7285a491 2004-06-17 devnull 	writepath(cd, c, 1, size);
103 7285a491 2004-06-17 devnull 	len = addlength(len, little(c->dlen, 4), wp);
104 7285a491 2004-06-17 devnull 	wp++;
105 7285a491 2004-06-17 devnull 
106 7285a491 2004-06-17 devnull 	while(rp < wp) {
107 7285a491 2004-06-17 devnull 		Crdpath(cd, &p);
108 7285a491 2004-06-17 devnull 		n = (len[rp]+Blocksize-1)/Blocksize;
109 7285a491 2004-06-17 devnull 		rp++;
110 7285a491 2004-06-17 devnull 		bk = (size==Big ? big : little)(p.dloc, 4);
111 7285a491 2004-06-17 devnull 		rdoff = Croffset(cd);
112 7285a491 2004-06-17 devnull 		for(i=0; i<n; i++) {
113 7285a491 2004-06-17 devnull 			Creadblock(cd, buf, bk+i, Blocksize);
114 7285a491 2004-06-17 devnull 			c = (Cdir*)buf;
115 7285a491 2004-06-17 devnull 			if(i != 0 && c->namelen == 1 && c->name[0] == '\0')	/* hit another directory; stop */
116 7285a491 2004-06-17 devnull 				break;
117 7285a491 2004-06-17 devnull 			while(c->len && c->namelen && (uchar*)c+c->len < buf+Blocksize) {
118 7285a491 2004-06-17 devnull 				if((c->flags & 0x02) && (c->namelen > 1 || c->name[0] > '\001')) {	/* directory */
119 7285a491 2004-06-17 devnull 					writepath(cd, c, rp, size);
120 7285a491 2004-06-17 devnull 					len = addlength(len, little(c->dlen, 4), wp);
121 7285a491 2004-06-17 devnull 					wp++;
122 7285a491 2004-06-17 devnull 				}
123 7285a491 2004-06-17 devnull 				c = (Cdir*)((uchar*)c+c->len);
124 7285a491 2004-06-17 devnull 			}
125 7285a491 2004-06-17 devnull 		}
126 7285a491 2004-06-17 devnull 		Crseek(cd, rdoff);
127 7285a491 2004-06-17 devnull 	}
128 7285a491 2004-06-17 devnull 	end = Cwoffset(cd);
129 7285a491 2004-06-17 devnull 	Cpadblock(cd);
130 7285a491 2004-06-17 devnull 	return end-start;
131 7285a491 2004-06-17 devnull }
132 7285a491 2004-06-17 devnull 
133 7285a491 2004-06-17 devnull 
134 7285a491 2004-06-17 devnull static void
135 7285a491 2004-06-17 devnull writepathtablepair(Cdimg *cd, ulong vdblock)
136 7285a491 2004-06-17 devnull {
137 7285a491 2004-06-17 devnull 	ulong bloc, lloc, sz, sz2;
138 7285a491 2004-06-17 devnull 
139 7285a491 2004-06-17 devnull 	lloc = cd->nextblock;
140 7285a491 2004-06-17 devnull 	sz = writepathtable(cd, vdblock, Little);
141 7285a491 2004-06-17 devnull 	bloc = cd->nextblock;
142 7285a491 2004-06-17 devnull 	sz2 = writepathtable(cd, vdblock, Big);
143 7285a491 2004-06-17 devnull 	assert(sz == sz2);
144 7285a491 2004-06-17 devnull 	setpathtable(cd, vdblock, sz, lloc, bloc);
145 7285a491 2004-06-17 devnull }
146 7285a491 2004-06-17 devnull 
147 7285a491 2004-06-17 devnull void
148 7285a491 2004-06-17 devnull writepathtables(Cdimg *cd)
149 7285a491 2004-06-17 devnull {
150 7285a491 2004-06-17 devnull 	cd->pathblock = cd->nextblock;
151 7285a491 2004-06-17 devnull 
152 7285a491 2004-06-17 devnull 	writepathtablepair(cd, cd->iso9660pvd);
153 7285a491 2004-06-17 devnull 	if(cd->flags & CDjoliet)
154 7285a491 2004-06-17 devnull 		writepathtablepair(cd, cd->jolietsvd);
155 7285a491 2004-06-17 devnull }