2ec1e693 |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: txport.c,v 1.1 2002/01/25 19:34:45 mdw Exp $ |
4 | * |
5 | * Transport switch glue |
6 | * |
7 | * (c) 2001 Mark Wooding |
8 | */ |
9 | |
10 | /*----- Licensing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of Jog: Programming for a jogging machine. |
13 | * |
14 | * Jog is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU General Public License as published by |
16 | * the Free Software Foundation; either version 2 of the License, or |
17 | * (at your option) any later version. |
18 | * |
19 | * Jog is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU General Public License |
25 | * along with Jog; if not, write to the Free Software Foundation, |
26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
27 | */ |
28 | |
29 | /*----- Revision history --------------------------------------------------* |
30 | * |
31 | * $Log: txport.c,v $ |
32 | * Revision 1.1 2002/01/25 19:34:45 mdw |
33 | * Initial revision |
34 | * |
35 | */ |
36 | |
37 | /*----- Header files ------------------------------------------------------*/ |
38 | |
39 | #ifdef HAVE_CONFIG_H |
40 | # include "config.h" |
41 | #endif |
42 | |
43 | #include <errno.h> |
44 | #include <stdio.h> |
45 | #include <stdarg.h> |
46 | |
47 | #include <sys/types.h> |
48 | #include <sys/time.h> |
49 | #include <unistd.h> |
50 | #include <pthread.h> |
51 | |
52 | #include <mLib/darray.h> |
53 | #include <mLib/dstr.h> |
54 | #include <mLib/lbuf.h> |
55 | #include <mLib/sub.h> |
56 | #include <mLib/trace.h> |
57 | #include <mLib/tv.h> |
58 | |
59 | #include "err.h" |
60 | #include "txport.h" |
61 | |
62 | /*----- Global variables --------------------------------------------------*/ |
63 | |
64 | #define TX_LIST 0 |
65 | #include "tx-socket.h" |
66 | #include "tx-serial-unix.h" |
67 | txport_ops *txlist = TX_LIST; |
68 | |
69 | const char *txname = 0; |
70 | const char *txfile = 0; |
71 | const char *txconf = 0; |
72 | |
73 | /*----- Main code ---------------------------------------------------------*/ |
74 | |
75 | /* --- @newline@ --- * |
76 | * |
77 | * Arguments: @char *s@ = pointer to line |
78 | * @size_t len@ = length of line |
79 | * @void *txv@ = pointer to transport context |
80 | * |
81 | * Returns: --- |
82 | * |
83 | * Use: Adds a line to the list. |
84 | */ |
85 | |
86 | static void newline(char *s, size_t len, void *txv) |
87 | { |
88 | txport *tx = txv; |
89 | txline *l; |
90 | |
91 | if (!s) |
92 | return; |
93 | l = CREATE(txline); |
94 | l->s = xmalloc(len + 1); |
95 | memcpy(l->s, s, len + 1); |
96 | l->len = len; |
97 | l->tx = tx; |
98 | l->next = 0; |
99 | l->prev = tx->ll_tail; |
100 | if (tx->ll_tail) |
101 | tx->ll_tail->next = l; |
102 | else |
103 | tx->ll = l; |
104 | tx->ll_tail = l; |
105 | } |
106 | |
107 | /* --- @tx_create@ --- * |
108 | * |
109 | * Arguments: @const char *name@ = name of transport to instantiate |
110 | * @const char *file@ = filename for transport |
111 | * @const char *config@ = config string |
112 | * |
113 | * Returns: A pointer to the transport context, or null on error. |
114 | * |
115 | * Use: Creates a new transport. |
116 | */ |
117 | |
118 | txport *tx_create(const char *name, const char *file, const char *config) |
119 | { |
120 | txport_ops *o; |
121 | txport *tx; |
122 | pthread_attr_t ta; |
123 | dstr d = DSTR_INIT; |
124 | size_t len; |
125 | int e; |
126 | |
127 | /* --- Look up the transport by name --- */ |
128 | |
129 | if (!name) { |
130 | o = txlist; |
131 | goto found; |
132 | } |
133 | len = strlen(name); |
134 | for (o = txlist; o; o = o->next) { |
135 | if (strncmp(name, o->name, len) == 0) |
136 | goto found; |
137 | } |
138 | err_report(ERR_TXPORT, ERRTX_BADTX, 0, "unknown transport `%s'", name); |
139 | return (0); |
140 | |
141 | /* --- Set up the transport block --- */ |
142 | |
143 | found: |
144 | if (!file) { |
145 | const struct txfile *fv; |
146 | for (fv = o->fv; fv->env || fv->name; fv++) { |
147 | if (fv->env && (file = getenv(fv->env)) == 0) |
148 | continue; |
149 | DRESET(&d); |
150 | if (file) |
151 | DPUTS(&d, file); |
152 | if (file && fv->name) |
153 | DPUTC(&d, '/'); |
154 | if (fv->name) |
155 | DPUTS(&d, fv->name); |
156 | break; |
157 | } |
158 | file = d.buf; |
159 | } |
160 | if (!config) |
161 | config = o->config; |
162 | if ((tx = o->create(file, config)) == 0) |
163 | goto fail_0; |
164 | tx->ops = o; |
165 | DA_CREATE(&tx->buf); |
166 | tx->ll = 0; |
167 | tx->ll_tail = 0; |
168 | if ((e = pthread_mutex_init(&tx->mx, 0)) != 0) { |
169 | err_report(ERR_TXPORT, ERRTX_CREATE, e, |
170 | "mutex creation failed: %s", strerror(e)); |
171 | goto fail_1; |
172 | } |
173 | if ((e = pthread_cond_init(&tx->cv, 0)) != 0) { |
174 | err_report(ERR_TXPORT, ERRTX_CREATE, e, |
175 | "condvar creation failed: %s", strerror(e)); |
176 | goto fail_2; |
177 | } |
178 | if ((e = pthread_attr_init(&ta)) != 0) { |
179 | err_report(ERR_TXPORT, ERRTX_CREATE, e, |
180 | "thread attribute creation failed: %s", strerror(e)); |
181 | goto fail_3; |
182 | } |
183 | if ((e = pthread_attr_setdetachstate(&ta, PTHREAD_CREATE_DETACHED)) || |
184 | (e = pthread_create(&tx->tid, &ta, tx->ops->fetch, tx)) != 0) { |
185 | err_report(ERR_TXPORT, ERRTX_CREATE, e, |
186 | "thread creation failed: %s", strerror(e)); |
187 | goto fail_4; |
188 | } |
189 | pthread_attr_destroy(&ta); |
190 | lbuf_init(&tx->lb, newline, tx); |
191 | tx->lb.delim = '\r'; |
192 | tx->s = TX_READY; |
193 | DDESTROY(&d); |
194 | return (tx); |
195 | |
196 | /* --- Something went wrong --- */ |
197 | |
198 | fail_4: |
199 | pthread_attr_destroy(&ta); |
200 | fail_3: |
201 | pthread_cond_destroy(&tx->cv); |
202 | fail_2: |
203 | pthread_mutex_destroy(&tx->mx); |
204 | fail_1: |
205 | tx->ops->destroy(tx); |
206 | fail_0: |
207 | DDESTROY(&d); |
208 | return (0); |
209 | } |
210 | |
211 | /* --- @tx_write@ --- * |
212 | * |
213 | * Arguments: @txport *tx@ = pointer to transport context |
214 | * @const void *p@ = pointer to buffer to write |
215 | * @size_t sz@ = size of buffer |
216 | * |
217 | * Returns: Zero if OK, or @-1@ on error. |
218 | * |
219 | * Use: Writes some data to a transport. |
220 | */ |
221 | |
222 | int tx_write(txport *tx, const void *p, size_t sz) |
223 | { |
224 | if (tx->ops->write(tx, p, sz) < 0) { |
225 | err_report(ERR_TXPORT, ERRTX_WRITE, errno, |
226 | "error writing to transport: %s", strerror(errno)); |
227 | return (-1); |
228 | } |
229 | return (0); |
230 | } |
231 | |
232 | /* --- @tx_printf@ --- * |
233 | * |
234 | * Arguments: @txport *tx@ = pointer to transport context |
235 | * @const char *p@ = pointer to string to write |
236 | * |
237 | * Returns: The number of characters printed, or @EOF@ on error. |
238 | * |
239 | * Use: Writes a textual message to a transport. |
240 | */ |
241 | |
242 | int tx_vprintf(txport *tx, const char *p, va_list *ap) |
243 | { |
244 | dstr d = DSTR_INIT; |
245 | int rc; |
246 | |
247 | dstr_vputf(&d, p, *ap); |
248 | rc = d.len; |
249 | rc = tx_write(tx, d.buf, d.len); |
250 | DDESTROY(&d); |
251 | return (rc); |
252 | } |
253 | |
254 | int tx_printf(txport *tx, const char *p, ...) |
255 | { |
256 | va_list ap; |
257 | int rc; |
258 | |
259 | va_start(ap, p); |
260 | rc = tx_vprintf(tx, p, &ap); |
261 | va_end(ap); |
262 | return (rc); |
263 | } |
264 | |
265 | /* --- @tx_read@, @tx_readx@ --- * |
266 | * |
267 | * Arguments: @txport *tx@ = pointer to transport context |
268 | * @unsigned long t@ = time to wait for data (ms) |
269 | * @int (*filter)(const char *s, void *p)@ = filtering function |
270 | * @void *p@ = pointer argument for filter |
271 | * |
272 | * Returns: A pointer to a line block, which must be freed using |
273 | * @tx_freeline@. |
274 | * |
275 | * Use: Fetches a line from the buffer. Each line is passed to the |
276 | * filter function in oldest-to-newest order; the filter |
277 | * function returns nonzero to choose a line. If no suitable |
278 | * line is waiting in the raw buffer, the program blocks while |
279 | * more data is fetched, until the time limit @t@ is exceeded, |
280 | * in which case a null pointer is returned. A null filter |
281 | * function is equivalent to one which always selects its line. |
282 | */ |
283 | |
284 | txline *tx_readx(txport *tx, unsigned long t, |
285 | int (*filter)(const char *s, void *p), void *p) |
286 | { |
287 | txline *l, **ll = &tx->ll; |
288 | int e; |
289 | struct timeval now, tv; |
290 | struct timespec ts; |
291 | unsigned f = 0; |
292 | |
293 | #define f_lock 1u |
294 | |
295 | /* --- Get the time to wait until --- */ |
296 | |
297 | if (t != FOREVER) { |
298 | gettimeofday(&now, 0); |
299 | tv_addl(&tv, &now, t / 1000, (t % 1000) * 1000); |
300 | ts.tv_sec = tv.tv_sec; |
301 | ts.tv_nsec = tv.tv_usec * 1000; |
302 | } |
303 | |
304 | /* --- Check for a matching line --- */ |
305 | |
306 | again: |
307 | for (; *ll; ll = &l->next) { |
308 | l = *ll; |
309 | if (!filter || filter(l->s, p)) |
310 | goto done; |
311 | } |
312 | l = 0; |
313 | |
314 | /* --- Lock the buffer --- * |
315 | * |
316 | * The following operations require a lock on the buffer, so we obtain that |
317 | * here. |
318 | */ |
319 | |
320 | if (!(f & f_lock)) { |
321 | if ((e = pthread_mutex_lock(&tx->mx)) != 0) { |
322 | err_report(ERR_TXPORT, ERRTX_READ, e, |
323 | "error locking mutex: %s", strerror(errno)); |
324 | goto done; |
325 | } |
326 | f |= f_lock; |
327 | } |
328 | |
329 | /* --- Push more stuff through the line buffer --- */ |
330 | |
331 | check: |
332 | if (DA_LEN(&tx->buf)) { |
333 | trace_block(1u, "incoming data", DA(&tx->buf), DA_LEN(&tx->buf)); |
334 | lbuf_snarf(&tx->lb, DA(&tx->buf), DA_LEN(&tx->buf)); |
335 | DA_SHRINK(&tx->buf, DA_LEN(&tx->buf)); |
336 | goto again; |
337 | } |
338 | |
339 | /* --- If nothing else can arrive, give up --- */ |
340 | |
341 | if (tx->s == TX_CLOSE) { |
342 | lbuf_close(&tx->lb); |
343 | tx->s = TX_CLOSED; |
344 | goto again; |
345 | } |
346 | if (!t || tx->s == TX_CLOSED) |
347 | goto done; |
348 | gettimeofday(&now, 0); |
349 | if (TV_CMP(&now, >=, &tv)) |
350 | goto done; |
351 | |
352 | /* --- Wait for some more data to arrive --- */ |
353 | |
354 | if (t == FOREVER) |
355 | e = pthread_cond_wait(&tx->cv, &tx->mx); |
356 | else |
357 | e = pthread_cond_timedwait(&tx->cv, &tx->mx, &ts); |
358 | if (e && e != ETIMEDOUT && e != EINTR) { |
359 | err_report(ERR_TXPORT, ERRTX_READ, e, |
360 | "error waiting on condvar: %s", strerror(errno)); |
361 | goto done; |
362 | } |
363 | goto check; |
364 | |
365 | /* --- Everything is finished --- */ |
366 | |
367 | done: |
368 | if (f & f_lock) |
369 | pthread_mutex_unlock(&tx->mx); |
370 | return (l); |
371 | |
372 | #undef f_lock |
373 | } |
374 | |
375 | txline *tx_read(txport *tx, unsigned long t) |
376 | { |
377 | return (tx_readx(tx, t, 0, 0)); |
378 | } |
379 | |
380 | /* --- @tx_freeline@ --- * |
381 | * |
382 | * Arguments: @txline *l@ = pointer to line |
383 | * |
384 | * Returns: --- |
385 | * |
386 | * Use: Frees a line block. |
387 | */ |
388 | |
389 | void tx_freeline(txline *l) |
390 | { |
391 | txport *tx = l->tx; |
392 | if (l->next) |
393 | l->next->prev = l->prev; |
394 | else |
395 | tx->ll_tail = l->prev; |
396 | if (l->prev) |
397 | l->prev->next = l->next; |
398 | else |
399 | tx->ll = l->next; |
400 | xfree(l->s); |
401 | DESTROY(l); |
402 | } |
403 | |
404 | /* --- @tx_destroy@ --- * |
405 | * |
406 | * Arguments: @txport *tx@ = transport context |
407 | * |
408 | * Returns: --- |
409 | * |
410 | * Use: Destroys a transport. |
411 | */ |
412 | |
413 | void tx_destroy(txport *tx) |
414 | { |
415 | txline *l, *ll; |
416 | |
417 | if (tx->s == TX_READY) { |
418 | pthread_mutex_lock(&tx->mx); |
419 | if (tx->s == TX_READY) |
420 | pthread_cancel(tx->tid); |
421 | pthread_mutex_unlock(&tx->mx); |
422 | } |
423 | pthread_mutex_destroy(&tx->mx); |
424 | pthread_cond_destroy(&tx->cv); |
425 | DA_DESTROY(&tx->buf); |
426 | lbuf_destroy(&tx->lb); |
427 | for (l = tx->ll; l; l = ll) { |
428 | ll = l->next; |
429 | xfree(l->s); |
430 | DESTROY(l); |
431 | } |
432 | tx->ops->destroy(tx); |
433 | } |
434 | |
435 | /*----- That's all, folks -------------------------------------------------*/ |