1 7763a61a 2003-11-23 devnull #include "stdinc.h"
  2 7763a61a 2003-11-23 devnull #include "vac.h"
  3 7763a61a 2003-11-23 devnull #include "dat.h"
  4 7763a61a 2003-11-23 devnull #include "fns.h"
  5 7763a61a 2003-11-23 devnull #include "error.h"
  6 7763a61a 2003-11-23 devnull 
  7 7763a61a 2003-11-23 devnull static int	sizeToDepth(uvlong s, int psize, int dsize);
  8 7763a61a 2003-11-23 devnull 
  9 7763a61a 2003-11-23 devnull static int
 10 7763a61a 2003-11-23 devnull sizeToDepth(uvlong s, int psize, int dsize)
 11 7763a61a 2003-11-23 devnull {
 12 7763a61a 2003-11-23 devnull 	int np;
 13 7763a61a 2003-11-23 devnull 	int d;
 14 7763a61a 2003-11-23 devnull 	
 15 7763a61a 2003-11-23 devnull 	/* determine pointer depth */
 16 7763a61a 2003-11-23 devnull 	np = psize/VtScoreSize;
 17 7763a61a 2003-11-23 devnull 	s = (s + dsize - 1)/dsize;
 18 7763a61a 2003-11-23 devnull 	for(d = 0; s > 1; d++)
 19 7763a61a 2003-11-23 devnull 		s = (s + np - 1)/np;
 20 7763a61a 2003-11-23 devnull 	return d;
 21 7763a61a 2003-11-23 devnull }
 22 7763a61a 2003-11-23 devnull 
 23 7763a61a 2003-11-23 devnull /* assumes u is lock? */
 24 7763a61a 2003-11-23 devnull Source *
 25 7763a61a 2003-11-23 devnull sourceAlloc(Cache *c, Lump *u, ulong block, int entry, int readOnly)
 26 7763a61a 2003-11-23 devnull {
 27 7763a61a 2003-11-23 devnull 	Source *r;
 28 7763a61a 2003-11-23 devnull 	VtEntry d;
 29 7763a61a 2003-11-23 devnull 
 30 7763a61a 2003-11-23 devnull 	if(u->asize < (entry+1)*VtEntrySize) {
 31 7763a61a 2003-11-23 devnull 		vtSetError(ENoDir);
 32 7763a61a 2003-11-23 devnull 		return nil;
 33 7763a61a 2003-11-23 devnull 	}
 34 7763a61a 2003-11-23 devnull 
 35 7763a61a 2003-11-23 devnull 	if(!vtEntryUnpack(&d, u->data, entry))
 36 7763a61a 2003-11-23 devnull 		return nil;
 37 7763a61a 2003-11-23 devnull 	
 38 7763a61a 2003-11-23 devnull 	if(!(d.flags & VtEntryActive)) {
 39 7763a61a 2003-11-23 devnull fprint(2, "bad flags %#ux %V\n", d.flags, d.score);
 40 7763a61a 2003-11-23 devnull 		vtSetError(ENoDir);
 41 7763a61a 2003-11-23 devnull 		return nil;
 42 7763a61a 2003-11-23 devnull 	}
 43 7763a61a 2003-11-23 devnull 	
 44 7763a61a 2003-11-23 devnull 	/* HACK for backwards compatiblity - should go away at some point */
 45 7763a61a 2003-11-23 devnull 	if(d.depth == 0) {
 46 7763a61a 2003-11-23 devnull if(d.size > d.dsize) fprint(2, "depth == 0! size = %ulld\n", d.size);
 47 7763a61a 2003-11-23 devnull 		d.depth = sizeToDepth(d.size, d.psize, d.dsize);
 48 7763a61a 2003-11-23 devnull 	}
 49 7763a61a 2003-11-23 devnull 
 50 7763a61a 2003-11-23 devnull 	if(d.depth < sizeToDepth(d.size, d.psize, d.dsize)) {
 51 7763a61a 2003-11-23 devnull 		vtSetError(EBadDir);
 52 7763a61a 2003-11-23 devnull 		return nil;
 53 7763a61a 2003-11-23 devnull 	}
 54 7763a61a 2003-11-23 devnull 
 55 7763a61a 2003-11-23 devnull 	r = vtMemAllocZ(sizeof(Source));
 56 7763a61a 2003-11-23 devnull 	r->lk = vtLockAlloc();
 57 7763a61a 2003-11-23 devnull 	r->cache = c;
 58 7763a61a 2003-11-23 devnull 	r->readOnly = readOnly;
 59 7763a61a 2003-11-23 devnull 	r->lump = lumpIncRef(u);
 60 7763a61a 2003-11-23 devnull 	r->block = block;
 61 7763a61a 2003-11-23 devnull 	r->entry = entry;
 62 7763a61a 2003-11-23 devnull 	r->gen = d.gen;
 63 7763a61a 2003-11-23 devnull 	r->dir = (d.flags & VtEntryDir) != 0;
 64 7763a61a 2003-11-23 devnull 	r->depth = d.depth;
 65 7763a61a 2003-11-23 devnull 	r->psize = d.psize;
 66 7763a61a 2003-11-23 devnull 	r->dsize = d.dsize;
 67 7763a61a 2003-11-23 devnull 	r->size = d.size;
 68 7763a61a 2003-11-23 devnull 
 69 7763a61a 2003-11-23 devnull 	r->epb = r->dsize/VtEntrySize;
 70 7763a61a 2003-11-23 devnull 
 71 7763a61a 2003-11-23 devnull 	return r;
 72 7763a61a 2003-11-23 devnull }
 73 7763a61a 2003-11-23 devnull 
 74 7763a61a 2003-11-23 devnull Source *
 75 7763a61a 2003-11-23 devnull sourceOpen(Source *r, ulong entry, int readOnly)
 76 7763a61a 2003-11-23 devnull {
 77 7763a61a 2003-11-23 devnull 	ulong bn;
 78 7763a61a 2003-11-23 devnull 	Lump *u;
 79 7763a61a 2003-11-23 devnull 
 80 7763a61a 2003-11-23 devnull if(0)fprint(2, "sourceOpen: %V:%d: %lud\n", r->lump->score, r->entry, entry);
 81 7763a61a 2003-11-23 devnull 	if(r->readOnly && !readOnly) {
 82 7763a61a 2003-11-23 devnull 		vtSetError(EReadOnly);
 83 7763a61a 2003-11-23 devnull 		return nil;
 84 7763a61a 2003-11-23 devnull 	}
 85 7763a61a 2003-11-23 devnull 
 86 7763a61a 2003-11-23 devnull 	bn = entry/r->epb;
 87 7763a61a 2003-11-23 devnull 
 88 7763a61a 2003-11-23 devnull 	u = sourceGetLump(r, bn, readOnly, 1);
 89 7763a61a 2003-11-23 devnull 	if(u == nil)
 90 7763a61a 2003-11-23 devnull 		return nil;
 91 7763a61a 2003-11-23 devnull 
 92 7763a61a 2003-11-23 devnull 	r = sourceAlloc(r->cache, u, bn, entry%r->epb, readOnly);
 93 7763a61a 2003-11-23 devnull 	lumpDecRef(u, 1);
 94 7763a61a 2003-11-23 devnull 	return r;
 95 7763a61a 2003-11-23 devnull }
 96 7763a61a 2003-11-23 devnull 
 97 7763a61a 2003-11-23 devnull Source *
 98 7763a61a 2003-11-23 devnull sourceCreate(Source *r, int psize, int dsize, int isdir, ulong entry)
 99 7763a61a 2003-11-23 devnull {
100 7763a61a 2003-11-23 devnull 	Source *rr;
101 7763a61a 2003-11-23 devnull 	int i;
102 7763a61a 2003-11-23 devnull 	Lump *u;
103 7763a61a 2003-11-23 devnull 	ulong bn;
104 7763a61a 2003-11-23 devnull 	VtEntry dir;
105 7763a61a 2003-11-23 devnull 
106 7763a61a 2003-11-23 devnull 	if(r->readOnly) {
107 7763a61a 2003-11-23 devnull 		vtSetError(EReadOnly);
108 7763a61a 2003-11-23 devnull 		return nil;
109 7763a61a 2003-11-23 devnull 	}
110 7763a61a 2003-11-23 devnull 
111 7763a61a 2003-11-23 devnull 	if(entry == 0) {
112 7763a61a 2003-11-23 devnull 		/*
113 7763a61a 2003-11-23 devnull 		 * look at a random block to see if we can find an empty entry
114 7763a61a 2003-11-23 devnull 		 */
115 7763a61a 2003-11-23 devnull 		entry = sourceGetDirSize(r);
116 7763a61a 2003-11-23 devnull 		entry = r->epb*lnrand(entry/r->epb+1);
117 7763a61a 2003-11-23 devnull 	}
118 7763a61a 2003-11-23 devnull 
119 7763a61a 2003-11-23 devnull 	/*
120 7763a61a 2003-11-23 devnull 	 * need to loop since multiple threads could be trying to allocate
121 7763a61a 2003-11-23 devnull 	 */
122 7763a61a 2003-11-23 devnull 	for(;;) {
123 7763a61a 2003-11-23 devnull 		bn = entry/r->epb;
124 7763a61a 2003-11-23 devnull 		sourceSetDepth(r, (uvlong)(bn+1)*r->dsize);
125 7763a61a 2003-11-23 devnull 		u = sourceGetLump(r, bn, 0, 1);
126 7763a61a 2003-11-23 devnull 		if(u == nil)
127 7763a61a 2003-11-23 devnull 			return nil;
128 7763a61a 2003-11-23 devnull 		for(i=entry%r->epb; i<r->epb; i++) {
129 7763a61a 2003-11-23 devnull 			vtEntryUnpack(&dir, u->data, i);
130 7763a61a 2003-11-23 devnull 			if((dir.flags&VtEntryActive) == 0 && dir.gen != ~0)
131 7763a61a 2003-11-23 devnull 				goto Found;
132 7763a61a 2003-11-23 devnull 		}
133 7763a61a 2003-11-23 devnull 		lumpDecRef(u, 1);
134 7763a61a 2003-11-23 devnull 		entry = sourceGetDirSize(r);
135 7763a61a 2003-11-23 devnull 	}
136 7763a61a 2003-11-23 devnull Found:
137 7763a61a 2003-11-23 devnull 	/* found an entry */
138 7763a61a 2003-11-23 devnull 	dir.psize = psize;
139 7763a61a 2003-11-23 devnull 	dir.dsize = dsize;
140 7763a61a 2003-11-23 devnull 	dir.flags = VtEntryActive;
141 7763a61a 2003-11-23 devnull 	if(isdir)
142 7763a61a 2003-11-23 devnull 		dir.flags |= VtEntryDir;
143 7763a61a 2003-11-23 devnull 	dir.depth = 0;
144 7763a61a 2003-11-23 devnull 	dir.size = 0;
145 7763a61a 2003-11-23 devnull 	memmove(dir.score, vtZeroScore, VtScoreSize);
146 7763a61a 2003-11-23 devnull 	vtEntryPack(&dir, u->data, i);
147 7763a61a 2003-11-23 devnull 
148 7763a61a 2003-11-23 devnull 	sourceSetDirSize(r, bn*r->epb + i + 1);
149 7763a61a 2003-11-23 devnull 	rr = sourceAlloc(r->cache, u, bn, i, 0);
150 7763a61a 2003-11-23 devnull 	
151 7763a61a 2003-11-23 devnull 	lumpDecRef(u, 1);
152 7763a61a 2003-11-23 devnull 	return rr;
153 7763a61a 2003-11-23 devnull }
154 7763a61a 2003-11-23 devnull 
155 7763a61a 2003-11-23 devnull void
156 7763a61a 2003-11-23 devnull sourceRemove(Source *r)
157 7763a61a 2003-11-23 devnull {
158 7763a61a 2003-11-23 devnull 	lumpFreeEntry(r->lump, r->entry);
159 7763a61a 2003-11-23 devnull 	sourceFree(r);
160 7763a61a 2003-11-23 devnull }
161 7763a61a 2003-11-23 devnull 
162 7763a61a 2003-11-23 devnull int
163 7763a61a 2003-11-23 devnull sourceSetDepth(Source *r, uvlong size)
164 7763a61a 2003-11-23 devnull {
165 7763a61a 2003-11-23 devnull 	Lump *u, *v;
166 7763a61a 2003-11-23 devnull 	VtEntry dir;
167 7763a61a 2003-11-23 devnull 	int depth;
168 7763a61a 2003-11-23 devnull 
169 7763a61a 2003-11-23 devnull 	if(r->readOnly){
170 7763a61a 2003-11-23 devnull 		vtSetError(EReadOnly);
171 7763a61a 2003-11-23 devnull 		return 0;
172 7763a61a 2003-11-23 devnull 	}
173 7763a61a 2003-11-23 devnull 
174 7763a61a 2003-11-23 devnull 	depth = sizeToDepth(size, r->psize, r->dsize);
175 7763a61a 2003-11-23 devnull 
176 7763a61a 2003-11-23 devnull 	assert(depth >= 0);
177 7763a61a 2003-11-23 devnull 
178 7763a61a 2003-11-23 devnull 	if(depth > VtPointerDepth) {
179 7763a61a 2003-11-23 devnull 		vtSetError(ETooBig);
180 7763a61a 2003-11-23 devnull 		return 0;
181 7763a61a 2003-11-23 devnull 	}
182 7763a61a 2003-11-23 devnull 
183 7763a61a 2003-11-23 devnull 	vtLock(r->lk);
184 7763a61a 2003-11-23 devnull 
185 7763a61a 2003-11-23 devnull 	if(r->depth >= depth) {
186 7763a61a 2003-11-23 devnull 		vtUnlock(r->lk);
187 7763a61a 2003-11-23 devnull 		return 1;
188 7763a61a 2003-11-23 devnull 	}
189 7763a61a 2003-11-23 devnull 	
190 7763a61a 2003-11-23 devnull 	u = r->lump;
191 7763a61a 2003-11-23 devnull 	vtLock(u->lk);
192 7763a61a 2003-11-23 devnull 	if(!vtEntryUnpack(&dir, u->data, r->entry)) {
193 7763a61a 2003-11-23 devnull 		vtUnlock(u->lk);
194 7763a61a 2003-11-23 devnull 		vtUnlock(r->lk);
195 7763a61a 2003-11-23 devnull 		return 0;
196 7763a61a 2003-11-23 devnull 	}
197 7763a61a 2003-11-23 devnull 	while(dir.depth < depth) {
198 7763a61a 2003-11-23 devnull 		v = cacheAllocLump(r->cache, VtPointerType0+r->depth, r->psize, r->dir);
199 7763a61a 2003-11-23 devnull 		if(v == nil)
200 7763a61a 2003-11-23 devnull 			break;
201 7763a61a 2003-11-23 devnull 		memmove(v->data, dir.score, VtScoreSize);
202 7763a61a 2003-11-23 devnull 		memmove(dir.score, v->score, VtScoreSize);
203 7763a61a 2003-11-23 devnull 		dir.depth++;
204 7763a61a 2003-11-23 devnull 		vtUnlock(v->lk);
205 7763a61a 2003-11-23 devnull 	}
206 7763a61a 2003-11-23 devnull 	vtEntryPack(&dir, u->data, r->entry);
207 7763a61a 2003-11-23 devnull 	vtUnlock(u->lk);
208 7763a61a 2003-11-23 devnull 
209 7763a61a 2003-11-23 devnull 	r->depth = dir.depth;
210 7763a61a 2003-11-23 devnull 	vtUnlock(r->lk);
211 7763a61a 2003-11-23 devnull 
212 7763a61a 2003-11-23 devnull 	return dir.depth == depth;
213 7763a61a 2003-11-23 devnull }
214 7763a61a 2003-11-23 devnull 
215 7763a61a 2003-11-23 devnull int
216 7763a61a 2003-11-23 devnull sourceGetVtEntry(Source *r, VtEntry *dir)
217 7763a61a 2003-11-23 devnull {
218 7763a61a 2003-11-23 devnull 	Lump *u;
219 7763a61a 2003-11-23 devnull 
220 7763a61a 2003-11-23 devnull 	u = r->lump;
221 7763a61a 2003-11-23 devnull 	vtLock(u->lk);
222 7763a61a 2003-11-23 devnull 	if(!vtEntryUnpack(dir, u->data, r->entry)) {
223 7763a61a 2003-11-23 devnull 		vtUnlock(u->lk);
224 7763a61a 2003-11-23 devnull 		return 0;
225 7763a61a 2003-11-23 devnull 	}
226 7763a61a 2003-11-23 devnull 	vtUnlock(u->lk);
227 7763a61a 2003-11-23 devnull 	return 1;
228 7763a61a 2003-11-23 devnull }
229 7763a61a 2003-11-23 devnull 
230 7763a61a 2003-11-23 devnull uvlong
231 7763a61a 2003-11-23 devnull sourceGetSize(Source *r)
232 7763a61a 2003-11-23 devnull {
233 7763a61a 2003-11-23 devnull 	uvlong size;
234 7763a61a 2003-11-23 devnull 
235 7763a61a 2003-11-23 devnull 	vtLock(r->lk);
236 7763a61a 2003-11-23 devnull 	size = r->size;
237 7763a61a 2003-11-23 devnull 	vtUnlock(r->lk);
238 7763a61a 2003-11-23 devnull 
239 7763a61a 2003-11-23 devnull 	return size;
240 7763a61a 2003-11-23 devnull }
241 7763a61a 2003-11-23 devnull 
242 7763a61a 2003-11-23 devnull 
243 7763a61a 2003-11-23 devnull int
244 7763a61a 2003-11-23 devnull sourceSetSize(Source *r, uvlong size)
245 7763a61a 2003-11-23 devnull {
246 7763a61a 2003-11-23 devnull 	Lump *u;
247 7763a61a 2003-11-23 devnull 	VtEntry dir;
248 7763a61a 2003-11-23 devnull 	int depth;
249 7763a61a 2003-11-23 devnull 
250 7763a61a 2003-11-23 devnull 	if(r->readOnly) {
251 7763a61a 2003-11-23 devnull 		vtSetError(EReadOnly);
252 7763a61a 2003-11-23 devnull 		return 0;
253 7763a61a 2003-11-23 devnull 	}
254 7763a61a 2003-11-23 devnull 
255 7763a61a 2003-11-23 devnull 	if(size > VtMaxFileSize || size > ((uvlong)MaxBlock)*r->dsize) {
256 7763a61a 2003-11-23 devnull 		vtSetError(ETooBig);
257 7763a61a 2003-11-23 devnull 		return 0;
258 7763a61a 2003-11-23 devnull 	}
259 7763a61a 2003-11-23 devnull 
260 7763a61a 2003-11-23 devnull 	vtLock(r->lk);
261 7763a61a 2003-11-23 devnull 	depth = sizeToDepth(size, r->psize, r->dsize);
262 7763a61a 2003-11-23 devnull 	if(size < r->size) {
263 7763a61a 2003-11-23 devnull 		vtUnlock(r->lk);
264 7763a61a 2003-11-23 devnull 		return 1;
265 7763a61a 2003-11-23 devnull 	}
266 7763a61a 2003-11-23 devnull 	if(depth > r->depth) {
267 7763a61a 2003-11-23 devnull 		vtSetError(EBadDir);
268 7763a61a 2003-11-23 devnull 		vtUnlock(r->lk);
269 7763a61a 2003-11-23 devnull 		return 0;
270 7763a61a 2003-11-23 devnull 	}
271 7763a61a 2003-11-23 devnull 	
272 7763a61a 2003-11-23 devnull 	u = r->lump;
273 7763a61a 2003-11-23 devnull 	vtLock(u->lk);
274 7763a61a 2003-11-23 devnull 	vtEntryUnpack(&dir, u->data, r->entry);
275 7763a61a 2003-11-23 devnull 	dir.size = size;
276 7763a61a 2003-11-23 devnull 	vtEntryPack(&dir, u->data, r->entry);
277 7763a61a 2003-11-23 devnull 	vtUnlock(u->lk);
278 7763a61a 2003-11-23 devnull 	r->size = size;
279 7763a61a 2003-11-23 devnull 	vtUnlock(r->lk);
280 7763a61a 2003-11-23 devnull 	return 1;
281 7763a61a 2003-11-23 devnull }
282 7763a61a 2003-11-23 devnull 
283 7763a61a 2003-11-23 devnull int
284 7763a61a 2003-11-23 devnull sourceSetDirSize(Source *r, ulong ds)
285 7763a61a 2003-11-23 devnull {
286 7763a61a 2003-11-23 devnull 	uvlong size;
287 7763a61a 2003-11-23 devnull 
288 7763a61a 2003-11-23 devnull 	size = (uvlong)r->dsize*(ds/r->epb);
289 7763a61a 2003-11-23 devnull 	size += VtEntrySize*(ds%r->epb);
290 7763a61a 2003-11-23 devnull 	return sourceSetSize(r, size);
291 7763a61a 2003-11-23 devnull }
292 7763a61a 2003-11-23 devnull 
293 7763a61a 2003-11-23 devnull ulong
294 7763a61a 2003-11-23 devnull sourceGetDirSize(Source *r)
295 7763a61a 2003-11-23 devnull {
296 7763a61a 2003-11-23 devnull 	ulong ds;
297 7763a61a 2003-11-23 devnull 	uvlong size;
298 7763a61a 2003-11-23 devnull 
299 7763a61a 2003-11-23 devnull 	size = sourceGetSize(r);
300 7763a61a 2003-11-23 devnull 	ds = r->epb*(size/r->dsize);
301 7763a61a 2003-11-23 devnull 	ds += (size%r->dsize)/VtEntrySize;
302 7763a61a 2003-11-23 devnull 	return ds;
303 7763a61a 2003-11-23 devnull }
304 7763a61a 2003-11-23 devnull 
305 7763a61a 2003-11-23 devnull ulong
306 7763a61a 2003-11-23 devnull sourceGetNumBlocks(Source *r)
307 7763a61a 2003-11-23 devnull {
308 7763a61a 2003-11-23 devnull 	return (sourceGetSize(r)+r->dsize-1)/r->dsize;
309 7763a61a 2003-11-23 devnull }
310 7763a61a 2003-11-23 devnull 
311 7763a61a 2003-11-23 devnull Lump *
312 7763a61a 2003-11-23 devnull sourceWalk(Source *r, ulong block, int readOnly, int *off)
313 7763a61a 2003-11-23 devnull {
314 7763a61a 2003-11-23 devnull 	int depth;
315 7763a61a 2003-11-23 devnull 	int i, np;
316 7763a61a 2003-11-23 devnull 	Lump *u, *v;
317 7763a61a 2003-11-23 devnull 	int elem[VtPointerDepth+1];
318 7763a61a 2003-11-23 devnull 	ulong b;
319 7763a61a 2003-11-23 devnull 
320 7763a61a 2003-11-23 devnull 	if(r->readOnly && !readOnly) {
321 7763a61a 2003-11-23 devnull 		vtSetError(EReadOnly);
322 7763a61a 2003-11-23 devnull 		return nil;
323 7763a61a 2003-11-23 devnull 	}
324 7763a61a 2003-11-23 devnull 
325 7763a61a 2003-11-23 devnull 	vtLock(r->lk);
326 7763a61a 2003-11-23 devnull 	np = r->psize/VtScoreSize;
327 7763a61a 2003-11-23 devnull 	b = block;
328 7763a61a 2003-11-23 devnull 	for(i=0; i<r->depth; i++) {
329 7763a61a 2003-11-23 devnull 		elem[i] = b % np;
330 7763a61a 2003-11-23 devnull 		b /= np;
331 7763a61a 2003-11-23 devnull 	}
332 7763a61a 2003-11-23 devnull 	if(b != 0) {
333 7763a61a 2003-11-23 devnull 		vtUnlock(r->lk);
334 7763a61a 2003-11-23 devnull 		vtSetError(EBadOffset);
335 7763a61a 2003-11-23 devnull 		return nil;
336 7763a61a 2003-11-23 devnull 	}
337 7763a61a 2003-11-23 devnull 	elem[i] = r->entry;
338 7763a61a 2003-11-23 devnull 	u = lumpIncRef(r->lump);
339 7763a61a 2003-11-23 devnull 	depth = r->depth;
340 7763a61a 2003-11-23 devnull 	*off = elem[0];
341 7763a61a 2003-11-23 devnull 	vtUnlock(r->lk);
342 7763a61a 2003-11-23 devnull 
343 7763a61a 2003-11-23 devnull 	for(i=depth; i>0; i--) {
344 7763a61a 2003-11-23 devnull 		v = lumpWalk(u, elem[i], VtPointerType0+i-1, r->psize, readOnly, 0);
345 7763a61a 2003-11-23 devnull 		lumpDecRef(u, 0);
346 7763a61a 2003-11-23 devnull 		if(v == nil)
347 7763a61a 2003-11-23 devnull 			return nil;
348 7763a61a 2003-11-23 devnull 		u = v;
349 7763a61a 2003-11-23 devnull 	}
350 7763a61a 2003-11-23 devnull 
351 7763a61a 2003-11-23 devnull 	return u;
352 7763a61a 2003-11-23 devnull }
353 7763a61a 2003-11-23 devnull 
354 7763a61a 2003-11-23 devnull Lump *
355 7763a61a 2003-11-23 devnull sourceGetLump(Source *r, ulong block, int readOnly, int lock)
356 7763a61a 2003-11-23 devnull {
357 7763a61a 2003-11-23 devnull 	int type, off;
358 7763a61a 2003-11-23 devnull 	Lump *u, *v;
359 7763a61a 2003-11-23 devnull 
360 7763a61a 2003-11-23 devnull 	if(r->readOnly && !readOnly) {
361 7763a61a 2003-11-23 devnull 		vtSetError(EReadOnly);
362 7763a61a 2003-11-23 devnull 		return nil;
363 7763a61a 2003-11-23 devnull 	}
364 7763a61a 2003-11-23 devnull 	if(block == NilBlock) {
365 7763a61a 2003-11-23 devnull 		vtSetError(ENilBlock);
366 7763a61a 2003-11-23 devnull 		return nil;
367 7763a61a 2003-11-23 devnull 	}
368 7763a61a 2003-11-23 devnull if(0)fprint(2, "sourceGetLump: %V:%d %lud\n", r->lump->score, r->entry, block);
369 7763a61a 2003-11-23 devnull 	u = sourceWalk(r, block, readOnly, &off);
370 7763a61a 2003-11-23 devnull 	if(u == nil)
371 7763a61a 2003-11-23 devnull 		return nil;
372 7763a61a 2003-11-23 devnull 	if(r->dir)
373 7763a61a 2003-11-23 devnull 		type = VtDirType;
374 7763a61a 2003-11-23 devnull 	else
375 7763a61a 2003-11-23 devnull 		type = VtDataType;
376 7763a61a 2003-11-23 devnull 	v = lumpWalk(u, off, type, r->dsize, readOnly, lock);
377 7763a61a 2003-11-23 devnull 	lumpDecRef(u, 0);
378 7763a61a 2003-11-23 devnull 	return v;
379 7763a61a 2003-11-23 devnull }
380 7763a61a 2003-11-23 devnull 
381 7763a61a 2003-11-23 devnull void
382 7763a61a 2003-11-23 devnull sourceFree(Source *k)
383 7763a61a 2003-11-23 devnull {
384 7763a61a 2003-11-23 devnull 	if(k == nil)
385 7763a61a 2003-11-23 devnull 		return;
386 7763a61a 2003-11-23 devnull 	lumpDecRef(k->lump, 0);
387 7763a61a 2003-11-23 devnull 	vtLockFree(k->lk);
388 7763a61a 2003-11-23 devnull 	memset(k, ~0, sizeof(*k));
389 7763a61a 2003-11-23 devnull 	vtMemFree(k);
390 7763a61a 2003-11-23 devnull }