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comparison src/console.c @ 24:36bd61f5c847

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rewrite sys_read cbc
author mir3636
date Thu, 17 Jan 2019 19:11:19 +0900
parents 83c23a36980d
children a146855e16eb
comparison
equal deleted inserted replaced
23:ee58360d0e99 24:36bd61f5c847
213 } 213 }
214 214
215 release(&input.lock); 215 release(&input.lock);
216 } 216 }
217 217
218 __code cbc_consoleread (struct inode *ip, char *dst, int n, __code(*next)(int ret))
219 {
220 uint target;
221 int c;
222
223 iunlock(ip);
224
225 target = n;
226 acquire(&input.lock);
227
228 while (n > 0) {
229 while (input.r == input.w) {
230 if (proc->killed) {
231 release(&input.lock);
232 ilock(ip);
233 goto next(-1);
234 }
235
236 proc->cbc_arg.cbc_console_arg.n = n;
237 proc->cbc_arg.cbc_console_arg.dst = dst;
238 proc->cbc_arg.cbc_console_arg.ip = ip;
239 proc->cbc_arg.cbc_console_arg.next = next;
240 goto cbc_sleep(&input.r, &input.lock, cbc_consoleread1);
241 }
242 }
243
244 __code cbc_consoleread1 (__code(*next)(int ret))
245 {
246 int cont = 1;
247 proc->cbc_arg.cbc_console_arg.n = n;
248 proc->cbc_arg.cbc_console_arg.dst = dst;
249 proc->cbc_arg.cbc_console_arg.ip = ip;
250
251 c = input.buf[input.r++ % INPUT_BUF];
252
253 if (c == C('D')) { // EOF
254 if (n < target) {
255 // Save ^D for next time, to make sure
256 // caller gets a 0-byte result.
257 input.r--;
258 }
259 cont = 0;
260 }
261
262 *dst++ = c;
263 --n;
264
265 if (c == '\n') {
266 cont = 0;
267 }
268
269
270 if (cont){
271 proc->cbc_arg.cbc_console_arg.n = n;
272 proc->cbc_arg.cbc_console_arg.dst = dst;
273 proc->cbc_arg.cbc_console_arg.ip = ip;
274 proc->cbc_arg.cbc_console_arg.next = next;
275 goto cbc_sleep(&input.r, &input.lock, cbc_consoleread1);
276 }
277
278 release(&input.lock);
279 ilock(ip);
280
281 goto next(target - n);
282 }
283
218 int consoleread (struct inode *ip, char *dst, int n) 284 int consoleread (struct inode *ip, char *dst, int n)
219 { 285 {
220 uint target; 286 uint target;
221 int c; 287 int c;
222 288
286 initlock(&cons.lock, "console"); 352 initlock(&cons.lock, "console");
287 initlock(&input.lock, "input"); 353 initlock(&input.lock, "input");
288 354
289 devsw[CONSOLE].write = consolewrite; 355 devsw[CONSOLE].write = consolewrite;
290 devsw[CONSOLE].read = consoleread; 356 devsw[CONSOLE].read = consoleread;
357 cbc_devsw[CONSOLE].write = cbc_consolewrite;
358 cbc_devsw[CONSOLE].read = cbc_consoleread;
291 359
292 cons.locking = 1; 360 cons.locking = 1;
293 } 361 }
294 362