10 sizecache(Buffer *b, uint n)  in sizecache()  argument
12 	if(n <= b->cmax)  in sizecache()
14 	b->cmax = n+Slop;  in sizecache()
15 	b->c = runerealloc(b->c, b->cmax);  in sizecache()
20 addblock(Buffer *b, uint i, uint n)  in addblock()  argument
22 	if(i > b->nbl)  in addblock()
25 	b->bl = realloc(b->bl, (b->nbl+1)*sizeof b->bl[0]);  in addblock()
26 	if(i < b->nbl)  in addblock()
27 		memmove(b->bl+i+1, b->bl+i, (b->nbl-i)*sizeof(Block*));  in addblock()
28 	b->bl[i] = disknewblock(disk, n);  in addblock()
29 	b->nbl++;  in addblock()
35 delblock(Buffer *b, uint i)  in delblock()  argument
37 	if(i >= b->nbl)  in delblock()
40 	diskrelease(disk, b->bl[i]);  in delblock()
41 	b->nbl--;  in delblock()
42 	if(i < b->nbl)  in delblock()
43 		memmove(b->bl+i, b->bl+i+1, (b->nbl-i)*sizeof(Block*));  in delblock()
44 	b->bl = realloc(b->bl, b->nbl*sizeof b->bl[0]);  in delblock()
54 flush(Buffer *b)  in flush()  argument
56 	if(b->cdirty || b->cnc==0){  in flush()
57 		if(b->cnc == 0)  in flush()
58 			delblock(b, b->cbi);  in flush()
60 			diskwrite(disk, &b->bl[b->cbi], b->c, b->cnc);  in flush()
61 		b->cdirty = FALSE;  in flush()
67 setcache(Buffer *b, uint q0)  in setcache()  argument
72 	if(q0 > b->nc)  in setcache()
77 	if(b->nc == 0 || (b->cq<=q0 && q0<b->cq+b->cnc))  in setcache()
82 	if(q0==b->nc && q0==b->cq+b->cnc && b->cnc<=Maxblock)  in setcache()
84 	flush(b);  in setcache()
86 	if(q0 < b->cq){  in setcache()
90 		q = b->cq;  in setcache()
91 		i = b->cbi;  in setcache()
93 	blp = &b->bl[i];  in setcache()
94 	while(q+(*blp)->n <= q0 && q+(*blp)->n < b->nc){  in setcache()
98 		if(i >= b->nbl)  in setcache()
103 	b->cbi = i;  in setcache()
104 	b->cq = q;  in setcache()
105 	sizecache(b, bl->n);  in setcache()
106 	b->cnc = bl->n;  in setcache()
108 	diskread(disk, bl, b->c, b->cnc);  in setcache()
112 bufinsert(Buffer *b, uint q0, Rune *s, uint n)  in bufinsert()  argument
116 	if(q0 > b->nc)  in bufinsert()
120 		setcache(b, q0);  in bufinsert()
121 		off = q0-b->cq;  in bufinsert()
122 		if(b->cnc+n <= Maxblock){  in bufinsert()
124 			t = b->cnc+n;  in bufinsert()
126 			if(b->bl == nil){	/* allocate */  in bufinsert()
127 				if(b->cnc != 0)  in bufinsert()
129 				addblock(b, 0, t);  in bufinsert()
130 				b->cbi = 0;  in bufinsert()
132 			sizecache(b, t);  in bufinsert()
133 			runemove(b->c+off+m, b->c+off, b->cnc-off);  in bufinsert()
134 			runemove(b->c+off, s, m);  in bufinsert()
135 			b->cnc = t;  in bufinsert()
143 		if(q0==b->cq || q0==b->cq+b->cnc){  in bufinsert()
144 			if(b->cdirty)  in bufinsert()
145 				flush(b);  in bufinsert()
147 			if(b->bl == nil){	/* allocate */  in bufinsert()
148 				if(b->cnc != 0)  in bufinsert()
152 				i = b->cbi;  in bufinsert()
153 				if(q0 > b->cq)  in bufinsert()
156 			addblock(b, i, m);  in bufinsert()
157 			sizecache(b, m);  in bufinsert()
158 			runemove(b->c, s, m);  in bufinsert()
159 			b->cq = q0;  in bufinsert()
160 			b->cbi = i;  in bufinsert()
161 			b->cnc = m;  in bufinsert()
168 		m = b->cnc-off;  in bufinsert()
170 			i = b->cbi+1;  in bufinsert()
171 			addblock(b, i, m);  in bufinsert()
172 			diskwrite(disk, &b->bl[i], b->c+off, m);  in bufinsert()
173 			b->cnc -= m;  in bufinsert()
179 		m = min(n, Maxblock-b->cnc);  in bufinsert()
180 		sizecache(b, b->cnc+m);  in bufinsert()
181 		runemove(b->c+b->cnc, s, m);  in bufinsert()
182 		b->cnc += m;  in bufinsert()
184 		b->nc += m;  in bufinsert()
188 		b->cdirty = TRUE;  in bufinsert()
193 bufdelete(Buffer *b, uint q0, uint q1)  in bufdelete()  argument
197 	if(!(q0<=q1 && q0<=b->nc && q1<=b->nc))  in bufdelete()
200 		setcache(b, q0);  in bufdelete()
201 		off = q0-b->cq;  in bufdelete()
202 		if(q1 > b->cq+b->cnc)  in bufdelete()
203 			n = b->cnc - off;  in bufdelete()
206 		m = b->cnc - (off+n);  in bufdelete()
208 			runemove(b->c+off, b->c+off+n, m);  in bufdelete()
209 		b->cnc -= n;  in bufdelete()
210 		b->cdirty = TRUE;  in bufdelete()
212 		b->nc -= n;  in bufdelete()
217 bufload(Buffer *b, uint q0, int fd, int *nulls)  in bufload()  argument
224 	if(q0 > b->nc)  in bufload()
251 		bufinsert(b, q1, r, nr);  in bufload()
260 bufread(Buffer *b, uint q0, Rune *s, uint n)  in bufread()  argument
264 	if(!(q0<=b->nc && q0+n<=b->nc))  in bufread()
268 		setcache(b, q0);  in bufread()
269 		m = min(n, b->cnc-(q0-b->cq));  in bufread()
270 		runemove(s, b->c+(q0-b->cq), m);  in bufread()
278 bufreset(Buffer *b)  in bufreset()  argument
282 	b->nc = 0;  in bufreset()
283 	b->cnc = 0;  in bufreset()
284 	b->cq = 0;  in bufreset()
285 	b->cdirty = 0;  in bufreset()
286 	b->cbi = 0;  in bufreset()
288 	for(i=b->nbl-1; --i>=0; )  in bufreset()
289 		delblock(b, i);  in bufreset()
293 bufclose(Buffer *b)  in bufclose()  argument
295 	bufreset(b);  in bufclose()
296 	free(b->c);  in bufclose()
297 	b->c = nil;  in bufclose()
298 	b->cnc = 0;  in bufclose()
299 	free(b->bl);  in bufclose()
300 	b->bl = nil;  in bufclose()
301 	b->nbl = 0;  in bufclose()