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 typedef struct MetaChunk MetaChunk;
  8 7763a61a 2003-11-23 devnull 
  9 7763a61a 2003-11-23 devnull struct MetaChunk {
 10 7763a61a 2003-11-23 devnull 	ushort offset;
 11 7763a61a 2003-11-23 devnull 	ushort size;
 12 7763a61a 2003-11-23 devnull 	ushort index;
 13 7763a61a 2003-11-23 devnull };
 14 7763a61a 2003-11-23 devnull 
 15 3d77c87e 2004-03-15 devnull static int	stringunpack(char **s, uchar **p, int *n);
 16 7763a61a 2003-11-23 devnull 
 17 7763a61a 2003-11-23 devnull /*
 18 7763a61a 2003-11-23 devnull  * integer conversion routines
 19 7763a61a 2003-11-23 devnull  */
 20 7763a61a 2003-11-23 devnull #define	U8GET(p)	((p)[0])
 21 7763a61a 2003-11-23 devnull #define	U16GET(p)	(((p)[0]<<8)|(p)[1])
 22 7763a61a 2003-11-23 devnull #define	U32GET(p)	(((p)[0]<<24)|((p)[1]<<16)|((p)[2]<<8)|(p)[3])
 23 7763a61a 2003-11-23 devnull #define	U48GET(p)	(((uvlong)U16GET(p)<<32)|(uvlong)U32GET((p)+2))
 24 7763a61a 2003-11-23 devnull #define	U64GET(p)	(((uvlong)U32GET(p)<<32)|(uvlong)U32GET((p)+4))
 25 7763a61a 2003-11-23 devnull 
 26 3d77c87e 2004-03-15 devnull #define	U8PUT(p,v)	(p)[0]=(v)&0xFF
 27 3d77c87e 2004-03-15 devnull #define	U16PUT(p,v)	(p)[0]=((v)>>8)&0xFF;(p)[1]=(v)&0xFF
 28 3d77c87e 2004-03-15 devnull #define	U32PUT(p,v)	(p)[0]=((v)>>24)&0xFF;(p)[1]=((v)>>16)&0xFF;(p)[2]=((v)>>8)&0xFF;(p)[3]=(v)&0xFF
 29 7763a61a 2003-11-23 devnull #define	U48PUT(p,v,t32)	t32=(v)>>32;U16PUT(p,t32);t32=(v);U32PUT((p)+2,t32)
 30 7763a61a 2003-11-23 devnull #define	U64PUT(p,v,t32)	t32=(v)>>32;U32PUT(p,t32);t32=(v);U32PUT((p)+4,t32)
 31 7763a61a 2003-11-23 devnull 
 32 7763a61a 2003-11-23 devnull static int
 33 3d77c87e 2004-03-15 devnull stringunpack(char **s, uchar **p, int *n)
 34 7763a61a 2003-11-23 devnull {
 35 7763a61a 2003-11-23 devnull 	int nn;
 36 7763a61a 2003-11-23 devnull 
 37 7763a61a 2003-11-23 devnull 	if(*n < 2)
 38 3d77c87e 2004-03-15 devnull 		return -1;
 39 7763a61a 2003-11-23 devnull 	
 40 7763a61a 2003-11-23 devnull 	nn = U16GET(*p);
 41 7763a61a 2003-11-23 devnull 	*p += 2;
 42 7763a61a 2003-11-23 devnull 	*n -= 2;
 43 7763a61a 2003-11-23 devnull 	if(nn > *n)
 44 3d77c87e 2004-03-15 devnull 		return -1;
 45 3d77c87e 2004-03-15 devnull 	*s = vtmalloc(nn+1);
 46 7763a61a 2003-11-23 devnull 	memmove(*s, *p, nn);
 47 7763a61a 2003-11-23 devnull 	(*s)[nn] = 0;
 48 7763a61a 2003-11-23 devnull 	*p += nn;
 49 7763a61a 2003-11-23 devnull 	*n -= nn;
 50 3d77c87e 2004-03-15 devnull 	return 0;
 51 7763a61a 2003-11-23 devnull }
 52 7763a61a 2003-11-23 devnull 
 53 7763a61a 2003-11-23 devnull static int
 54 3d77c87e 2004-03-15 devnull stringpack(char *s, uchar *p)
 55 7763a61a 2003-11-23 devnull {
 56 7763a61a 2003-11-23 devnull 	int n;
 57 7763a61a 2003-11-23 devnull 
 58 7763a61a 2003-11-23 devnull 	n = strlen(s);
 59 7763a61a 2003-11-23 devnull 	U16PUT(p, n);
 60 7763a61a 2003-11-23 devnull 	memmove(p+2, s, n);
 61 7763a61a 2003-11-23 devnull 	return n+2;
 62 7763a61a 2003-11-23 devnull }
 63 7763a61a 2003-11-23 devnull 
 64 7763a61a 2003-11-23 devnull 
 65 7763a61a 2003-11-23 devnull int
 66 3d77c87e 2004-03-15 devnull mbunpack(MetaBlock *mb, uchar *p, int n)
 67 7763a61a 2003-11-23 devnull {
 68 7763a61a 2003-11-23 devnull 	u32int magic;
 69 7763a61a 2003-11-23 devnull 
 70 7763a61a 2003-11-23 devnull 	mb->maxsize = n;
 71 7763a61a 2003-11-23 devnull 	mb->buf = p;
 72 7763a61a 2003-11-23 devnull 
 73 7763a61a 2003-11-23 devnull 	if(n == 0) {
 74 7763a61a 2003-11-23 devnull 		memset(mb, 0, sizeof(MetaBlock));
 75 3d77c87e 2004-03-15 devnull 		return 0;
 76 7763a61a 2003-11-23 devnull 	}
 77 7763a61a 2003-11-23 devnull 
 78 7763a61a 2003-11-23 devnull 	magic = U32GET(p);
 79 7763a61a 2003-11-23 devnull 	if(magic != MetaMagic && magic != MetaMagic+1) {
 80 3d77c87e 2004-03-15 devnull 		werrstr("bad meta block magic");
 81 3d77c87e 2004-03-15 devnull 		return -1;
 82 7763a61a 2003-11-23 devnull 	}
 83 7763a61a 2003-11-23 devnull 	mb->size = U16GET(p+4);
 84 7763a61a 2003-11-23 devnull 	mb->free = U16GET(p+6);
 85 7763a61a 2003-11-23 devnull 	mb->maxindex = U16GET(p+8);
 86 7763a61a 2003-11-23 devnull 	mb->nindex = U16GET(p+10);
 87 7763a61a 2003-11-23 devnull 	mb->unbotch = (magic == MetaMagic+1);
 88 7763a61a 2003-11-23 devnull 
 89 7763a61a 2003-11-23 devnull 	if(mb->size > n) {
 90 3d77c87e 2004-03-15 devnull 		werrstr("bad meta block size");
 91 3d77c87e 2004-03-15 devnull 		return -1;
 92 7763a61a 2003-11-23 devnull 	}
 93 7763a61a 2003-11-23 devnull 	p += MetaHeaderSize;
 94 7763a61a 2003-11-23 devnull 	n -= MetaHeaderSize;
 95 7763a61a 2003-11-23 devnull 
 96 7763a61a 2003-11-23 devnull 	USED(p);
 97 7763a61a 2003-11-23 devnull 	if(n < mb->maxindex*MetaIndexSize) {
 98 3d77c87e 2004-03-15 devnull  		werrstr("truncated meta block 2");
 99 3d77c87e 2004-03-15 devnull 		return -1;
100 7763a61a 2003-11-23 devnull 	}
101 3d77c87e 2004-03-15 devnull 	return 0;
102 7763a61a 2003-11-23 devnull }
103 7763a61a 2003-11-23 devnull 
104 7763a61a 2003-11-23 devnull void
105 3d77c87e 2004-03-15 devnull mbpack(MetaBlock *mb)
106 7763a61a 2003-11-23 devnull {
107 7763a61a 2003-11-23 devnull 	uchar *p;
108 7763a61a 2003-11-23 devnull 
109 7763a61a 2003-11-23 devnull 	p = mb->buf;
110 7763a61a 2003-11-23 devnull 
111 7763a61a 2003-11-23 devnull 	U32PUT(p, MetaMagic);
112 7763a61a 2003-11-23 devnull 	U16PUT(p+4, mb->size);
113 7763a61a 2003-11-23 devnull 	U16PUT(p+6, mb->free);
114 7763a61a 2003-11-23 devnull 	U16PUT(p+8, mb->maxindex);
115 7763a61a 2003-11-23 devnull 	U16PUT(p+10, mb->nindex);
116 7763a61a 2003-11-23 devnull }
117 7763a61a 2003-11-23 devnull 
118 7763a61a 2003-11-23 devnull 
119 7763a61a 2003-11-23 devnull void
120 3d77c87e 2004-03-15 devnull mbdelete(MetaBlock *mb, int i, MetaEntry *me)
121 7763a61a 2003-11-23 devnull {
122 7763a61a 2003-11-23 devnull 	uchar *p;
123 7763a61a 2003-11-23 devnull 	int n;
124 7763a61a 2003-11-23 devnull 
125 7763a61a 2003-11-23 devnull 	assert(i < mb->nindex);
126 7763a61a 2003-11-23 devnull 
127 7763a61a 2003-11-23 devnull 	if(me->p - mb->buf + me->size == mb->size)
128 7763a61a 2003-11-23 devnull 		mb->size -= me->size;
129 7763a61a 2003-11-23 devnull 	else
130 7763a61a 2003-11-23 devnull 		mb->free += me->size;
131 7763a61a 2003-11-23 devnull 
132 7763a61a 2003-11-23 devnull 	p = mb->buf + MetaHeaderSize + i*MetaIndexSize;
133 7763a61a 2003-11-23 devnull 	n = (mb->nindex-i-1)*MetaIndexSize;
134 7763a61a 2003-11-23 devnull 	memmove(p, p+MetaIndexSize, n);
135 7763a61a 2003-11-23 devnull 	memset(p+n, 0, MetaIndexSize);
136 7763a61a 2003-11-23 devnull 	mb->nindex--;
137 7763a61a 2003-11-23 devnull }
138 7763a61a 2003-11-23 devnull 
139 7763a61a 2003-11-23 devnull void
140 3d77c87e 2004-03-15 devnull mbinsert(MetaBlock *mb, int i, MetaEntry *me)
141 7763a61a 2003-11-23 devnull {
142 7763a61a 2003-11-23 devnull 	uchar *p;
143 7763a61a 2003-11-23 devnull 	int o, n;
144 7763a61a 2003-11-23 devnull 
145 7763a61a 2003-11-23 devnull 	assert(mb->nindex < mb->maxindex);
146 7763a61a 2003-11-23 devnull 
147 7763a61a 2003-11-23 devnull 	o = me->p - mb->buf;
148 7763a61a 2003-11-23 devnull 	n = me->size;
149 7763a61a 2003-11-23 devnull 	if(o+n > mb->size) {
150 7763a61a 2003-11-23 devnull 		mb->free -= mb->size - o;
151 7763a61a 2003-11-23 devnull 		mb->size = o + n;
152 7763a61a 2003-11-23 devnull 	} else
153 7763a61a 2003-11-23 devnull 		mb->free -= n;
154 7763a61a 2003-11-23 devnull 
155 7763a61a 2003-11-23 devnull 	p = mb->buf + MetaHeaderSize + i*MetaIndexSize;
156 7763a61a 2003-11-23 devnull 	n = (mb->nindex-i)*MetaIndexSize;
157 7763a61a 2003-11-23 devnull 	memmove(p+MetaIndexSize, p, n);
158 7763a61a 2003-11-23 devnull 	U16PUT(p, me->p - mb->buf);
159 7763a61a 2003-11-23 devnull 	U16PUT(p+2, me->size);
160 7763a61a 2003-11-23 devnull 	mb->nindex++;
161 7763a61a 2003-11-23 devnull }
162 7763a61a 2003-11-23 devnull 
163 7763a61a 2003-11-23 devnull int
164 3d77c87e 2004-03-15 devnull meunpack(MetaEntry *me, MetaBlock *mb, int i)
165 7763a61a 2003-11-23 devnull {
166 7763a61a 2003-11-23 devnull 	uchar *p;
167 7763a61a 2003-11-23 devnull 	int eo, en;
168 7763a61a 2003-11-23 devnull 
169 7763a61a 2003-11-23 devnull 	if(i < 0 || i >= mb->nindex) {
170 3d77c87e 2004-03-15 devnull 		werrstr("bad meta entry index");
171 3d77c87e 2004-03-15 devnull 		return -1;
172 7763a61a 2003-11-23 devnull 	}
173 7763a61a 2003-11-23 devnull 
174 7763a61a 2003-11-23 devnull 	p = mb->buf + MetaHeaderSize + i*MetaIndexSize;
175 7763a61a 2003-11-23 devnull 	eo = U16GET(p);
176 7763a61a 2003-11-23 devnull 	en = U16GET(p+2);
177 7763a61a 2003-11-23 devnull 
178 7763a61a 2003-11-23 devnull if(0)print("eo = %d en = %d\n", eo, en);
179 7763a61a 2003-11-23 devnull 	if(eo < MetaHeaderSize + mb->maxindex*MetaIndexSize) {
180 3d77c87e 2004-03-15 devnull 		werrstr("corrupted entry in meta block");
181 3d77c87e 2004-03-15 devnull 		return -1;
182 7763a61a 2003-11-23 devnull 	}
183 7763a61a 2003-11-23 devnull 
184 7763a61a 2003-11-23 devnull 	if(eo+en > mb->size) {
185 3d77c87e 2004-03-15 devnull  		werrstr("truncated meta block");
186 3d77c87e 2004-03-15 devnull 		return -1;
187 7763a61a 2003-11-23 devnull 	}
188 7763a61a 2003-11-23 devnull 
189 7763a61a 2003-11-23 devnull 	p = mb->buf + eo;
190 7763a61a 2003-11-23 devnull 	
191 7763a61a 2003-11-23 devnull 	/* make sure entry looks ok and includes an elem name */
192 7763a61a 2003-11-23 devnull 	if(en < 8 || U32GET(p) != DirMagic || en < 8 + U16GET(p+6)) {
193 3d77c87e 2004-03-15 devnull 		werrstr("corrupted meta block entry");
194 3d77c87e 2004-03-15 devnull 		return -1;
195 7763a61a 2003-11-23 devnull 	}
196 7763a61a 2003-11-23 devnull 
197 7763a61a 2003-11-23 devnull 	me->p = p;
198 7763a61a 2003-11-23 devnull 	me->size = en;
199 7763a61a 2003-11-23 devnull 
200 3d77c87e 2004-03-15 devnull 	return 0;
201 7763a61a 2003-11-23 devnull }
202 7763a61a 2003-11-23 devnull 
203 7763a61a 2003-11-23 devnull /* assumes a small amount of checking has been done in mbEntry */
204 7763a61a 2003-11-23 devnull int
205 3d77c87e 2004-03-15 devnull mecmp(MetaEntry *me, char *s)
206 7763a61a 2003-11-23 devnull {
207 7763a61a 2003-11-23 devnull 	int n;
208 7763a61a 2003-11-23 devnull 	uchar *p;
209 7763a61a 2003-11-23 devnull 
210 7763a61a 2003-11-23 devnull 	p = me->p;
211 7763a61a 2003-11-23 devnull 
212 7763a61a 2003-11-23 devnull 	p += 6;
213 7763a61a 2003-11-23 devnull 	n = U16GET(p);
214 7763a61a 2003-11-23 devnull 	p += 2;
215 7763a61a 2003-11-23 devnull 
216 7763a61a 2003-11-23 devnull 	assert(n + 8 < me->size);
217 7763a61a 2003-11-23 devnull 
218 7763a61a 2003-11-23 devnull 	while(n > 0) {
219 7763a61a 2003-11-23 devnull 		if(*s == 0)
220 7763a61a 2003-11-23 devnull 			return -1;
221 7763a61a 2003-11-23 devnull 		if(*p < (uchar)*s)
222 7763a61a 2003-11-23 devnull 			return -1;
223 7763a61a 2003-11-23 devnull 		if(*p > (uchar)*s)
224 7763a61a 2003-11-23 devnull 			return 1;
225 7763a61a 2003-11-23 devnull 		p++;
226 7763a61a 2003-11-23 devnull 		s++;
227 7763a61a 2003-11-23 devnull 		n--;
228 7763a61a 2003-11-23 devnull 	}
229 7763a61a 2003-11-23 devnull 	return *s != 0;
230 7763a61a 2003-11-23 devnull }
231 7763a61a 2003-11-23 devnull 
232 7763a61a 2003-11-23 devnull int
233 3d77c87e 2004-03-15 devnull mecmpnew(MetaEntry *me, char *s)
234 7763a61a 2003-11-23 devnull {
235 7763a61a 2003-11-23 devnull 	int n;
236 7763a61a 2003-11-23 devnull 	uchar *p;
237 7763a61a 2003-11-23 devnull 
238 7763a61a 2003-11-23 devnull 	p = me->p;
239 7763a61a 2003-11-23 devnull 
240 7763a61a 2003-11-23 devnull 	p += 6;
241 7763a61a 2003-11-23 devnull 	n = U16GET(p);
242 7763a61a 2003-11-23 devnull 	p += 2;
243 7763a61a 2003-11-23 devnull 
244 7763a61a 2003-11-23 devnull 	assert(n + 8 < me->size);
245 7763a61a 2003-11-23 devnull 
246 7763a61a 2003-11-23 devnull 	while(n > 0) {
247 7763a61a 2003-11-23 devnull 		if(*s == 0)
248 7763a61a 2003-11-23 devnull 			return 1;
249 7763a61a 2003-11-23 devnull 		if(*p < (uchar)*s)
250 7763a61a 2003-11-23 devnull 			return -1;
251 7763a61a 2003-11-23 devnull 		if(*p > (uchar)*s)
252 7763a61a 2003-11-23 devnull 			return 1;
253 7763a61a 2003-11-23 devnull 		p++;
254 7763a61a 2003-11-23 devnull 		s++;
255 7763a61a 2003-11-23 devnull 		n--;
256 7763a61a 2003-11-23 devnull 	}
257 7763a61a 2003-11-23 devnull 	return -(*s != 0);
258 7763a61a 2003-11-23 devnull }
259 7763a61a 2003-11-23 devnull 
260 7763a61a 2003-11-23 devnull static int
261 3d77c87e 2004-03-15 devnull offsetcmp(const void *s0, const void *s1)
262 7763a61a 2003-11-23 devnull {
263 3d77c87e 2004-03-15 devnull 	const MetaChunk *mc0, *mc1;
264 7763a61a 2003-11-23 devnull 
265 7763a61a 2003-11-23 devnull 	mc0 = s0;
266 7763a61a 2003-11-23 devnull 	mc1 = s1;
267 7763a61a 2003-11-23 devnull 	if(mc0->offset < mc1->offset)
268 7763a61a 2003-11-23 devnull 		return -1;
269 7763a61a 2003-11-23 devnull 	if(mc0->offset > mc1->offset)
270 7763a61a 2003-11-23 devnull 		return 1;
271 7763a61a 2003-11-23 devnull 	return 0;
272 7763a61a 2003-11-23 devnull }
273 7763a61a 2003-11-23 devnull 
274 7763a61a 2003-11-23 devnull static MetaChunk *
275 3d77c87e 2004-03-15 devnull metachunks(MetaBlock *mb)
276 7763a61a 2003-11-23 devnull {
277 7763a61a 2003-11-23 devnull 	MetaChunk *mc;
278 7763a61a 2003-11-23 devnull 	int oo, o, n, i;
279 7763a61a 2003-11-23 devnull 	uchar *p;
280 7763a61a 2003-11-23 devnull 
281 3d77c87e 2004-03-15 devnull 	mc = vtmalloc(mb->nindex*sizeof(MetaChunk));
282 7763a61a 2003-11-23 devnull 	p = mb->buf + MetaHeaderSize;
283 7763a61a 2003-11-23 devnull 	for(i = 0; i<mb->nindex; i++) {
284 7763a61a 2003-11-23 devnull 		mc[i].offset = U16GET(p);
285 7763a61a 2003-11-23 devnull 		mc[i].size = U16GET(p+2);
286 7763a61a 2003-11-23 devnull 		mc[i].index = i;
287 7763a61a 2003-11-23 devnull 		p += MetaIndexSize;
288 7763a61a 2003-11-23 devnull 	}
289 7763a61a 2003-11-23 devnull 
290 3d77c87e 2004-03-15 devnull 	qsort(mc, mb->nindex, sizeof(MetaChunk), offsetcmp);
291 7763a61a 2003-11-23 devnull 
292 7763a61a 2003-11-23 devnull 	/* check block looks ok */
293 7763a61a 2003-11-23 devnull 	oo = MetaHeaderSize + mb->maxindex*MetaIndexSize;
294 7763a61a 2003-11-23 devnull 	o = oo;
295 7763a61a 2003-11-23 devnull 	n = 0;
296 7763a61a 2003-11-23 devnull 	for(i=0; i<mb->nindex; i++) {
297 7763a61a 2003-11-23 devnull 		o = mc[i].offset;
298 7763a61a 2003-11-23 devnull 		n = mc[i].size;
299 7763a61a 2003-11-23 devnull 		if(o < oo)
300 7763a61a 2003-11-23 devnull 			goto Err;
301 7763a61a 2003-11-23 devnull 		oo += n;
302 7763a61a 2003-11-23 devnull 	}
303 7763a61a 2003-11-23 devnull 	if(o+n <= mb->size)
304 7763a61a 2003-11-23 devnull 		goto Err;
305 7763a61a 2003-11-23 devnull 	if(mb->size - oo != mb->free)
306 7763a61a 2003-11-23 devnull 		goto Err;
307 7763a61a 2003-11-23 devnull 
308 7763a61a 2003-11-23 devnull 	return mc;
309 7763a61a 2003-11-23 devnull Err:
310 3d77c87e 2004-03-15 devnull 	vtfree(mc);
311 7763a61a 2003-11-23 devnull 	return nil;
312 7763a61a 2003-11-23 devnull }
313 7763a61a 2003-11-23 devnull 
314 7763a61a 2003-11-23 devnull static void
315 3d77c87e 2004-03-15 devnull mbcompact(MetaBlock *mb, MetaChunk *mc)
316 7763a61a 2003-11-23 devnull {
317 7763a61a 2003-11-23 devnull 	int oo, o, n, i;
318 7763a61a 2003-11-23 devnull 
319 7763a61a 2003-11-23 devnull 	oo = MetaHeaderSize + mb->maxindex*MetaIndexSize;
320 7763a61a 2003-11-23 devnull 	
321 7763a61a 2003-11-23 devnull 	for(i=0; i<mb->nindex; i++) {
322 7763a61a 2003-11-23 devnull 		o = mc[i].offset;
323 7763a61a 2003-11-23 devnull 		n = mc[i].size;
324 7763a61a 2003-11-23 devnull 		if(o != oo) {
325 7763a61a 2003-11-23 devnull 			memmove(mb->buf + oo, mb->buf + o, n);
326 7763a61a 2003-11-23 devnull 			U16PUT(mb->buf + MetaHeaderSize + mc[i].index*MetaIndexSize, oo);
327 7763a61a 2003-11-23 devnull 		}
328 7763a61a 2003-11-23 devnull 		oo += n;
329 7763a61a 2003-11-23 devnull 	}
330 7763a61a 2003-11-23 devnull 
331 7763a61a 2003-11-23 devnull 	mb->size = oo;
332 7763a61a 2003-11-23 devnull 	mb->free = 0;
333 7763a61a 2003-11-23 devnull }
334 7763a61a 2003-11-23 devnull 
335 7763a61a 2003-11-23 devnull uchar *
336 3d77c87e 2004-03-15 devnull mballoc(MetaBlock *mb, int n)
337 7763a61a 2003-11-23 devnull {
338 7763a61a 2003-11-23 devnull 	int i, o;
339 7763a61a 2003-11-23 devnull 	MetaChunk *mc;
340 7763a61a 2003-11-23 devnull 
341 7763a61a 2003-11-23 devnull 	/* off the end */
342 7763a61a 2003-11-23 devnull 	if(mb->maxsize - mb->size >= n)
343 7763a61a 2003-11-23 devnull 		return mb->buf + mb->size;
344 7763a61a 2003-11-23 devnull 
345 7763a61a 2003-11-23 devnull 	/* check if possible */
346 7763a61a 2003-11-23 devnull 	if(mb->maxsize - mb->size + mb->free < n)
347 7763a61a 2003-11-23 devnull 		return nil;
348 7763a61a 2003-11-23 devnull 
349 3d77c87e 2004-03-15 devnull 	mc = metachunks(mb);
350 7763a61a 2003-11-23 devnull 
351 7763a61a 2003-11-23 devnull 	/* look for hole */
352 7763a61a 2003-11-23 devnull 	o = MetaHeaderSize + mb->maxindex*MetaIndexSize;
353 7763a61a 2003-11-23 devnull 	for(i=0; i<mb->nindex; i++) {
354 7763a61a 2003-11-23 devnull 		if(mc[i].offset - o >= n) {
355 3d77c87e 2004-03-15 devnull 			vtfree(mc);
356 7763a61a 2003-11-23 devnull 			return mb->buf + o;
357 7763a61a 2003-11-23 devnull 		}
358 7763a61a 2003-11-23 devnull 		o = mc[i].offset + mc[i].size;
359 7763a61a 2003-11-23 devnull 	}
360 7763a61a 2003-11-23 devnull 
361 7763a61a 2003-11-23 devnull 	if(mb->maxsize - o >= n) {
362 3d77c87e 2004-03-15 devnull 		vtfree(mc);
363 7763a61a 2003-11-23 devnull 		return mb->buf + o;
364 7763a61a 2003-11-23 devnull 	}
365 7763a61a 2003-11-23 devnull 
366 7763a61a 2003-11-23 devnull 	/* compact and return off the end */
367 3d77c87e 2004-03-15 devnull 	mbcompact(mb, mc);
368 3d77c87e 2004-03-15 devnull 	vtfree(mc);
369 7763a61a 2003-11-23 devnull 
370 7763a61a 2003-11-23 devnull 	assert(mb->maxsize - mb->size >= n);
371 7763a61a 2003-11-23 devnull 	return mb->buf + mb->size;
372 7763a61a 2003-11-23 devnull }
373 7763a61a 2003-11-23 devnull 
374 7763a61a 2003-11-23 devnull int
375 3d77c87e 2004-03-15 devnull vdsize(VacDir *dir)
376 7763a61a 2003-11-23 devnull {
377 7763a61a 2003-11-23 devnull 	int n;
378 7763a61a 2003-11-23 devnull 	
379 7763a61a 2003-11-23 devnull 	/* constant part */
380 7763a61a 2003-11-23 devnull 
381 7763a61a 2003-11-23 devnull 	n = 	4 +	/* magic */
382 7763a61a 2003-11-23 devnull 		2 + 	/* version */
383 7763a61a 2003-11-23 devnull 		4 +	/* entry */
384 7763a61a 2003-11-23 devnull 		4 + 	/* guid */
385 7763a61a 2003-11-23 devnull 		4 + 	/* mentry */
386 7763a61a 2003-11-23 devnull 		4 + 	/* mgen */
387 7763a61a 2003-11-23 devnull 		8 +	/* qid */
388 7763a61a 2003-11-23 devnull 		4 + 	/* mtime */
389 7763a61a 2003-11-23 devnull 		4 + 	/* mcount */
390 7763a61a 2003-11-23 devnull 		4 + 	/* ctime */
391 7763a61a 2003-11-23 devnull 		4 + 	/* atime */
392 7763a61a 2003-11-23 devnull 		4 +	/* mode */
393 7763a61a 2003-11-23 devnull 		0;
394 7763a61a 2003-11-23 devnull 
395 7763a61a 2003-11-23 devnull 	/* strings */
396 7763a61a 2003-11-23 devnull 	n += 2 + strlen(dir->elem);
397 7763a61a 2003-11-23 devnull 	n += 2 + strlen(dir->uid);
398 7763a61a 2003-11-23 devnull 	n += 2 + strlen(dir->gid);
399 7763a61a 2003-11-23 devnull 	n += 2 + strlen(dir->mid);
400 7763a61a 2003-11-23 devnull 
401 7763a61a 2003-11-23 devnull 	/* optional sections */
402 3d77c87e 2004-03-15 devnull 	if(dir->qidspace) {
403 7763a61a 2003-11-23 devnull 		n += 	3 + 	/* option header */
404 3d77c87e 2004-03-15 devnull 			8 + 	/* qid offset */
405 3d77c87e 2004-03-15 devnull 			8;	/* qid max */
406 7763a61a 2003-11-23 devnull 	}
407 7763a61a 2003-11-23 devnull 
408 7763a61a 2003-11-23 devnull 	return n;
409 7763a61a 2003-11-23 devnull }
410 7763a61a 2003-11-23 devnull 
411 7763a61a 2003-11-23 devnull void
412 3d77c87e 2004-03-15 devnull vdpack(VacDir *dir, MetaEntry *me)
413 7763a61a 2003-11-23 devnull {
414 7763a61a 2003-11-23 devnull 	uchar *p;
415 7763a61a 2003-11-23 devnull 	ulong t32;
416 7763a61a 2003-11-23 devnull 
417 7763a61a 2003-11-23 devnull 	p = me->p;
418 7763a61a 2003-11-23 devnull 	
419 7763a61a 2003-11-23 devnull 	U32PUT(p, DirMagic);
420 7763a61a 2003-11-23 devnull 	U16PUT(p+4, 9);		/* version */
421 7763a61a 2003-11-23 devnull 	p += 6;
422 7763a61a 2003-11-23 devnull 
423 3d77c87e 2004-03-15 devnull 	p += stringpack(dir->elem, p);
424 7763a61a 2003-11-23 devnull 
425 7763a61a 2003-11-23 devnull 	U32PUT(p, dir->entry);
426 7763a61a 2003-11-23 devnull 	U32PUT(p+4, dir->gen);
427 7763a61a 2003-11-23 devnull 	U32PUT(p+8, dir->mentry);
428 7763a61a 2003-11-23 devnull 	U32PUT(p+12, dir->mgen);
429 7763a61a 2003-11-23 devnull 	U64PUT(p+16, dir->qid, t32);
430 7763a61a 2003-11-23 devnull 	p += 24;
431 7763a61a 2003-11-23 devnull 
432 3d77c87e 2004-03-15 devnull 	p += stringpack(dir->uid, p);
433 3d77c87e 2004-03-15 devnull 	p += stringpack(dir->gid, p);
434 3d77c87e 2004-03-15 devnull 	p += stringpack(dir->mid, p);
435 7763a61a 2003-11-23 devnull 	
436 7763a61a 2003-11-23 devnull 	U32PUT(p, dir->mtime);
437 7763a61a 2003-11-23 devnull 	U32PUT(p+4, dir->mcount);
438 7763a61a 2003-11-23 devnull 	U32PUT(p+8, dir->ctime);
439 7763a61a 2003-11-23 devnull 	U32PUT(p+12, dir->atime);
440 7763a61a 2003-11-23 devnull 	U32PUT(p+16, dir->mode);
441 7763a61a 2003-11-23 devnull 	p += 5*4;
442 7763a61a 2003-11-23 devnull 
443 3d77c87e 2004-03-15 devnull 	if(dir->qidspace) {
444 7763a61a 2003-11-23 devnull 		U8PUT(p, DirQidSpaceEntry);
445 7763a61a 2003-11-23 devnull 		U16PUT(p+1, 2*8);
446 7763a61a 2003-11-23 devnull 		p += 3;
447 3d77c87e 2004-03-15 devnull 		U64PUT(p, dir->qidoffset, t32);
448 3d77c87e 2004-03-15 devnull 		U64PUT(p+8, dir->qidmax, t32);
449 7763a61a 2003-11-23 devnull 	}
450 7763a61a 2003-11-23 devnull 
451 7763a61a 2003-11-23 devnull 	assert(p == me->p + me->size);
452 7763a61a 2003-11-23 devnull }
453 7763a61a 2003-11-23 devnull 
454 7763a61a 2003-11-23 devnull 
455 7763a61a 2003-11-23 devnull int
456 3d77c87e 2004-03-15 devnull vdunpack(VacDir *dir, MetaEntry *me)
457 7763a61a 2003-11-23 devnull {
458 7763a61a 2003-11-23 devnull 	int t, nn, n, version;
459 7763a61a 2003-11-23 devnull 	uchar *p;
460 7763a61a 2003-11-23 devnull 	
461 7763a61a 2003-11-23 devnull 	p = me->p;
462 7763a61a 2003-11-23 devnull 	n = me->size;
463 7763a61a 2003-11-23 devnull 
464 7763a61a 2003-11-23 devnull 	memset(dir, 0, sizeof(VacDir));
465 7763a61a 2003-11-23 devnull 
466 7763a61a 2003-11-23 devnull if(0)print("vdUnpack\n");
467 7763a61a 2003-11-23 devnull 	/* magic */
468 7763a61a 2003-11-23 devnull 	if(n < 4 || U32GET(p) != DirMagic)
469 7763a61a 2003-11-23 devnull 		goto Err;
470 7763a61a 2003-11-23 devnull 	p += 4;
471 7763a61a 2003-11-23 devnull 	n -= 4;
472 7763a61a 2003-11-23 devnull 
473 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got magic\n");
474 7763a61a 2003-11-23 devnull 	/* version */
475 7763a61a 2003-11-23 devnull 	if(n < 2)
476 7763a61a 2003-11-23 devnull 		goto Err;
477 7763a61a 2003-11-23 devnull 	version = U16GET(p);
478 7763a61a 2003-11-23 devnull 	if(version < 7 || version > 9)
479 7763a61a 2003-11-23 devnull 		goto Err;
480 7763a61a 2003-11-23 devnull 	p += 2;
481 7763a61a 2003-11-23 devnull 	n -= 2;	
482 7763a61a 2003-11-23 devnull 
483 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got version\n");
484 7763a61a 2003-11-23 devnull 
485 7763a61a 2003-11-23 devnull 	/* elem */
486 3d77c87e 2004-03-15 devnull 	if(stringunpack(&dir->elem, &p, &n) < 0)
487 7763a61a 2003-11-23 devnull 		goto Err;
488 7763a61a 2003-11-23 devnull 
489 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got elem\n");
490 7763a61a 2003-11-23 devnull 
491 7763a61a 2003-11-23 devnull 	/* entry  */
492 7763a61a 2003-11-23 devnull 	if(n < 4)
493 7763a61a 2003-11-23 devnull 		goto Err;
494 7763a61a 2003-11-23 devnull 	dir->entry = U32GET(p);
495 7763a61a 2003-11-23 devnull 	p += 4;
496 7763a61a 2003-11-23 devnull 	n -= 4;
497 7763a61a 2003-11-23 devnull 
498 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got entry\n");
499 7763a61a 2003-11-23 devnull 
500 7763a61a 2003-11-23 devnull 	if(version < 9) {
501 7763a61a 2003-11-23 devnull 		dir->gen = 0;
502 7763a61a 2003-11-23 devnull 		dir->mentry = dir->entry+1;
503 7763a61a 2003-11-23 devnull 		dir->mgen = 0;
504 7763a61a 2003-11-23 devnull 	} else {
505 7763a61a 2003-11-23 devnull 		if(n < 3*4)
506 7763a61a 2003-11-23 devnull 			goto Err;
507 7763a61a 2003-11-23 devnull 		dir->gen = U32GET(p);
508 7763a61a 2003-11-23 devnull 		dir->mentry = U32GET(p+4);
509 7763a61a 2003-11-23 devnull 		dir->mgen = U32GET(p+8);
510 7763a61a 2003-11-23 devnull 		p += 3*4;
511 7763a61a 2003-11-23 devnull 		n -= 3*4;
512 7763a61a 2003-11-23 devnull 	}
513 7763a61a 2003-11-23 devnull 
514 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got gen etc\n");
515 7763a61a 2003-11-23 devnull 
516 7763a61a 2003-11-23 devnull 	/* size is gotten from DirEntry */
517 7763a61a 2003-11-23 devnull 
518 7763a61a 2003-11-23 devnull 	/* qid */
519 7763a61a 2003-11-23 devnull 	if(n < 8)
520 7763a61a 2003-11-23 devnull 		goto Err;
521 7763a61a 2003-11-23 devnull 	dir->qid = U64GET(p);
522 7763a61a 2003-11-23 devnull 	p += 8;
523 7763a61a 2003-11-23 devnull 	n -= 8;
524 7763a61a 2003-11-23 devnull 
525 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got qid\n");
526 7763a61a 2003-11-23 devnull 	/* skip replacement */
527 7763a61a 2003-11-23 devnull 	if(version == 7) {
528 7763a61a 2003-11-23 devnull 		if(n < VtScoreSize)
529 7763a61a 2003-11-23 devnull 			goto Err;
530 7763a61a 2003-11-23 devnull 		p += VtScoreSize;
531 7763a61a 2003-11-23 devnull 		n -= VtScoreSize;
532 7763a61a 2003-11-23 devnull 	}
533 7763a61a 2003-11-23 devnull 	
534 7763a61a 2003-11-23 devnull 	/* uid */
535 3d77c87e 2004-03-15 devnull 	if(stringunpack(&dir->uid, &p, &n) < 0)
536 7763a61a 2003-11-23 devnull 		goto Err;
537 7763a61a 2003-11-23 devnull 
538 7763a61a 2003-11-23 devnull 	/* gid */
539 3d77c87e 2004-03-15 devnull 	if(stringunpack(&dir->gid, &p, &n) < 0)
540 7763a61a 2003-11-23 devnull 		goto Err;
541 7763a61a 2003-11-23 devnull 
542 7763a61a 2003-11-23 devnull 	/* mid */
543 3d77c87e 2004-03-15 devnull 	if(stringunpack(&dir->mid, &p, &n) < 0)
544 7763a61a 2003-11-23 devnull 		goto Err;
545 7763a61a 2003-11-23 devnull 
546 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got ids\n");
547 7763a61a 2003-11-23 devnull 	if(n < 5*4)
548 7763a61a 2003-11-23 devnull 		goto Err;
549 7763a61a 2003-11-23 devnull 	dir->mtime = U32GET(p);
550 7763a61a 2003-11-23 devnull 	dir->mcount = U32GET(p+4);
551 7763a61a 2003-11-23 devnull 	dir->ctime = U32GET(p+8);
552 7763a61a 2003-11-23 devnull 	dir->atime = U32GET(p+12);
553 7763a61a 2003-11-23 devnull 	dir->mode = U32GET(p+16);
554 7763a61a 2003-11-23 devnull 	p += 5*4;
555 7763a61a 2003-11-23 devnull 	n -= 5*4;
556 7763a61a 2003-11-23 devnull 
557 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got times\n");
558 7763a61a 2003-11-23 devnull 	/* optional meta data */
559 7763a61a 2003-11-23 devnull 	while(n > 0) {
560 7763a61a 2003-11-23 devnull 		if(n < 3)
561 7763a61a 2003-11-23 devnull 			goto Err;
562 7763a61a 2003-11-23 devnull 		t = p[0];
563 7763a61a 2003-11-23 devnull 		nn = U16GET(p+1);
564 7763a61a 2003-11-23 devnull 		p += 3;
565 7763a61a 2003-11-23 devnull 		n -= 3;
566 7763a61a 2003-11-23 devnull 		if(n < nn)
567 7763a61a 2003-11-23 devnull 			goto Err;
568 7763a61a 2003-11-23 devnull 		switch(t) {
569 7763a61a 2003-11-23 devnull 		case DirPlan9Entry:
570 7763a61a 2003-11-23 devnull 			/* not valid in version >= 9 */
571 7763a61a 2003-11-23 devnull 			if(version >= 9)
572 7763a61a 2003-11-23 devnull 				break;
573 7763a61a 2003-11-23 devnull 			if(dir->plan9 || nn != 12)
574 7763a61a 2003-11-23 devnull 				goto Err;
575 7763a61a 2003-11-23 devnull 			dir->plan9 = 1;
576 7763a61a 2003-11-23 devnull 			dir->p9path = U64GET(p);
577 7763a61a 2003-11-23 devnull 			dir->p9version = U32GET(p+8);
578 7763a61a 2003-11-23 devnull 			if(dir->mcount == 0)
579 7763a61a 2003-11-23 devnull 				dir->mcount = dir->p9version;
580 7763a61a 2003-11-23 devnull 			break;
581 7763a61a 2003-11-23 devnull 		case DirGenEntry:
582 7763a61a 2003-11-23 devnull 			/* not valid in version >= 9 */
583 7763a61a 2003-11-23 devnull 			if(version >= 9)
584 7763a61a 2003-11-23 devnull 				break;
585 7763a61a 2003-11-23 devnull 			break;
586 7763a61a 2003-11-23 devnull 		case DirQidSpaceEntry:
587 3d77c87e 2004-03-15 devnull 			if(dir->qidspace || nn != 16)
588 7763a61a 2003-11-23 devnull 				goto Err;
589 3d77c87e 2004-03-15 devnull 			dir->qidspace = 1;
590 3d77c87e 2004-03-15 devnull 			dir->qidoffset = U64GET(p);
591 3d77c87e 2004-03-15 devnull 			dir->qidmax = U64GET(p+8);
592 7763a61a 2003-11-23 devnull 			break;
593 7763a61a 2003-11-23 devnull 		}
594 7763a61a 2003-11-23 devnull 		p += nn;
595 7763a61a 2003-11-23 devnull 		n -= nn;
596 7763a61a 2003-11-23 devnull 	}
597 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: got options\n");
598 7763a61a 2003-11-23 devnull 
599 7763a61a 2003-11-23 devnull 	if(p != me->p + me->size)
600 7763a61a 2003-11-23 devnull 		goto Err;
601 7763a61a 2003-11-23 devnull 
602 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: correct size\n");
603 3d77c87e 2004-03-15 devnull 	return 0;
604 7763a61a 2003-11-23 devnull Err:
605 7763a61a 2003-11-23 devnull if(0)print("vdUnpack: XXXXXXXXXXXX EbadMeta\n");
606 3d77c87e 2004-03-15 devnull 	werrstr(EBadMeta);
607 3d77c87e 2004-03-15 devnull 	vdcleanup(dir);
608 3d77c87e 2004-03-15 devnull 	return -1;
609 7763a61a 2003-11-23 devnull }
610 3d77c87e 2004-03-15 devnull 
611 3d77c87e 2004-03-15 devnull void
612 3d77c87e 2004-03-15 devnull vdcleanup(VacDir *dir)
613 3d77c87e 2004-03-15 devnull {
614 3d77c87e 2004-03-15 devnull 	vtfree(dir->elem);
615 3d77c87e 2004-03-15 devnull 	dir->elem = nil;
616 3d77c87e 2004-03-15 devnull 	vtfree(dir->uid);
617 3d77c87e 2004-03-15 devnull 	dir->uid = nil;
618 3d77c87e 2004-03-15 devnull 	vtfree(dir->gid);
619 3d77c87e 2004-03-15 devnull 	dir->gid = nil;
620 3d77c87e 2004-03-15 devnull 	vtfree(dir->mid);
621 3d77c87e 2004-03-15 devnull 	dir->mid = nil;
622 3d77c87e 2004-03-15 devnull }
623 3d77c87e 2004-03-15 devnull 
624 3d77c87e 2004-03-15 devnull void
625 3d77c87e 2004-03-15 devnull vdcopy(VacDir *dst, VacDir *src)
626 3d77c87e 2004-03-15 devnull {
627 3d77c87e 2004-03-15 devnull 	*dst = *src;
628 3d77c87e 2004-03-15 devnull 	dst->elem = vtstrdup(dst->elem);
629 3d77c87e 2004-03-15 devnull 	dst->uid = vtstrdup(dst->uid);
630 3d77c87e 2004-03-15 devnull 	dst->gid = vtstrdup(dst->gid);
631 3d77c87e 2004-03-15 devnull 	dst->mid = vtstrdup(dst->mid);
632 3d77c87e 2004-03-15 devnull }
633 3d77c87e 2004-03-15 devnull 
634 3d77c87e 2004-03-15 devnull int
635 3d77c87e 2004-03-15 devnull mbsearch(MetaBlock *mb, char *elem, int *ri, MetaEntry *me)
636 3d77c87e 2004-03-15 devnull {
637 3d77c87e 2004-03-15 devnull 	int i;
638 3d77c87e 2004-03-15 devnull 	int b, t, x;
639 3d77c87e 2004-03-15 devnull 
640 3d77c87e 2004-03-15 devnull 	/* binary search within block */
641 3d77c87e 2004-03-15 devnull 	b = 0;
642 3d77c87e 2004-03-15 devnull 	t = mb->nindex;
643 3d77c87e 2004-03-15 devnull 	while(b < t) {
644 3d77c87e 2004-03-15 devnull 		i = (b+t)>>1;
645 3d77c87e 2004-03-15 devnull 		if(meunpack(me, mb, i) < 0)
646 3d77c87e 2004-03-15 devnull 			return 0;
647 3d77c87e 2004-03-15 devnull 		if(mb->unbotch)
648 3d77c87e 2004-03-15 devnull 			x = mecmpnew(me, elem);
649 3d77c87e 2004-03-15 devnull 		else
650 3d77c87e 2004-03-15 devnull 			x = mecmp(me, elem);
651 3d77c87e 2004-03-15 devnull 
652 3d77c87e 2004-03-15 devnull 		if(x == 0) {
653 3d77c87e 2004-03-15 devnull 			*ri = i;
654 3d77c87e 2004-03-15 devnull 			return 1;
655 3d77c87e 2004-03-15 devnull 		}
656 3d77c87e 2004-03-15 devnull 	
657 3d77c87e 2004-03-15 devnull 		if(x < 0)
658 3d77c87e 2004-03-15 devnull 			b = i+1;
659 3d77c87e 2004-03-15 devnull 		else /* x > 0 */
660 3d77c87e 2004-03-15 devnull 			t = i;
661 3d77c87e 2004-03-15 devnull 	}
662 3d77c87e 2004-03-15 devnull 
663 3d77c87e 2004-03-15 devnull 	assert(b == t);
664 3d77c87e 2004-03-15 devnull 	
665 3d77c87e 2004-03-15 devnull 	*ri = b;	/* b is the index to insert this entry */
666 3d77c87e 2004-03-15 devnull 	memset(me, 0, sizeof(*me));
667 3d77c87e 2004-03-15 devnull 
668 a20a1468 2005-01-16 devnull 	return -1;
669 3d77c87e 2004-03-15 devnull }
670 3d77c87e 2004-03-15 devnull 
671 3d77c87e 2004-03-15 devnull void
672 3d77c87e 2004-03-15 devnull mbinit(MetaBlock *mb, uchar *p, int n)
673 3d77c87e 2004-03-15 devnull {
674 3d77c87e 2004-03-15 devnull 	memset(mb, 0, sizeof(MetaBlock));
675 3d77c87e 2004-03-15 devnull 	mb->maxsize = n;
676 3d77c87e 2004-03-15 devnull 	mb->buf = p;
677 3d77c87e 2004-03-15 devnull 	mb->maxindex = n/100;
678 3d77c87e 2004-03-15 devnull 	mb->size = MetaHeaderSize + mb->maxindex*MetaIndexSize;
679 3d77c87e 2004-03-15 devnull }
680 3d77c87e 2004-03-15 devnull 
681 3d77c87e 2004-03-15 devnull int
682 3d77c87e 2004-03-15 devnull mbresize(MetaBlock *mb, MetaEntry *me, int n)
683 3d77c87e 2004-03-15 devnull {
684 3d77c87e 2004-03-15 devnull 	uchar *p, *ep;
685 3d77c87e 2004-03-15 devnull 
686 3d77c87e 2004-03-15 devnull 	/* easy case */
687 3d77c87e 2004-03-15 devnull 	if(n <= me->size){
688 3d77c87e 2004-03-15 devnull 		me->size = n;
689 3d77c87e 2004-03-15 devnull 		return 0;
690 3d77c87e 2004-03-15 devnull 	}
691 3d77c87e 2004-03-15 devnull 
692 3d77c87e 2004-03-15 devnull 	/* try and expand entry */
693 3d77c87e 2004-03-15 devnull 
694 3d77c87e 2004-03-15 devnull 	p = me->p + me->size;
695 3d77c87e 2004-03-15 devnull 	ep = mb->buf + mb->maxsize;
696 3d77c87e 2004-03-15 devnull 	while(p < ep && *p == 0)
697 3d77c87e 2004-03-15 devnull 		p++;
698 3d77c87e 2004-03-15 devnull 	if(n <= p - me->p){
699 3d77c87e 2004-03-15 devnull 		me->size = n;
700 3d77c87e 2004-03-15 devnull 		return 0;
701 3d77c87e 2004-03-15 devnull 	}
702 3d77c87e 2004-03-15 devnull 
703 3d77c87e 2004-03-15 devnull 	p = mballoc(mb, n);
704 3d77c87e 2004-03-15 devnull 	if(p != nil){
705 3d77c87e 2004-03-15 devnull 		me->p = p;
706 3d77c87e 2004-03-15 devnull 		me->size = n;
707 3d77c87e 2004-03-15 devnull 		return 0;
708 3d77c87e 2004-03-15 devnull 	}
709 3d77c87e 2004-03-15 devnull 
710 3d77c87e 2004-03-15 devnull 	return -1;
711 3d77c87e 2004-03-15 devnull }