Bug Summary

File:lwan-thread.c
Warning:line 778, column 31
Array subscript is undefined

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name lwan-thread.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -mframe-pointer=all -fmath-errno -fno-rounding-math -mconstructor-aliases -fno-plt -munwind-tables -target-cpu x86-64 -fno-split-dwarf-inlining -debugger-tuning=gdb -resource-dir /usr/lib/clang/11.0.1 -include /home/buildbot/lwan-worker/clang-analyze/build/lwan-build-config.h -D _FILE_OFFSET_BITS=64 -D _TIME_BITS=64 -I /home/buildbot/lwan-worker/clang-analyze/build/src/lib/missing -I /usr/include/luajit-2.0 -I /usr/include/valgrind -I /home/buildbot/lwan-worker/clang-analyze/build/src/lib -I /home/buildbot/lwan-worker/clang-analyze/build -internal-isystem /usr/local/include -internal-isystem /usr/lib/clang/11.0.1/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -Wno-unused-parameter -Wno-free-nonheap-object -std=gnu99 -fdebug-compilation-dir /home/buildbot/lwan-worker/clang-analyze/build/src/lib -ferror-limit 19 -stack-protector 2 -fgnuc-version=4.2.1 -analyzer-output=html -faddrsig -o /home/buildbot/lwan-worker/clang-analyze/CLANG/2021-02-05-015947-3949014-1 -x c /home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c
1/*
2 * lwan - simple web server
3 * Copyright (c) 2012, 2013 Leandro A. F. Pereira <leandro@hardinfo.org>
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; either version 2
8 * of the License, or any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
18 * USA.
19 */
20
21#define _GNU_SOURCE
22#include <assert.h>
23#include <errno(*__errno_location ()).h>
24#include <fcntl.h>
25#include <pthread.h>
26#include <sched.h>
27#include <stdlib.h>
28#include <string.h>
29#include <sys/epoll.h>
30#include <sys/ioctl.h>
31#include <sys/socket.h>
32#include <unistd.h>
33
34#if defined(HAVE_EVENTFD)
35#include <sys/eventfd.h>
36#endif
37
38#include "lwan-private.h"
39#include "lwan-tq.h"
40#include "list.h"
41
42static void lwan_strbuf_free_defer(void *data)
43{
44 lwan_strbuf_free((struct lwan_strbuf *)data);
45}
46
47static void graceful_close(struct lwan *l,
48 struct lwan_connection *conn,
49 char buffer[static DEFAULT_BUFFER_SIZE4096])
50{
51 int fd = lwan_connection_get_fd(l, conn);
52
53 while (TIOCOUTQ0x5411) {
54 /* This ioctl isn't probably doing what it says on the tin; the details
55 * are subtle, but it seems to do the trick to allow gracefully closing
56 * the connection in some cases with minimal system calls. */
57 int bytes_waiting;
58 int r = ioctl(fd, TIOCOUTQ0x5411, &bytes_waiting);
59
60 if (!r && !bytes_waiting) /* See note about close(2) below. */
61 return;
62 if (r < 0 && errno(*__errno_location ()) == EINTR4)
63 continue;
64
65 break;
66 }
67
68 if (UNLIKELY(shutdown(fd, SHUT_WR) < 0)__builtin_expect(((shutdown(fd, SHUT_WR) < 0)), (0))) {
69 if (UNLIKELY(errno == ENOTCONN)__builtin_expect((((*__errno_location ()) == 107)), (0)))
70 return;
71 }
72
73 for (int tries = 0; tries < 20; tries++) {
74 ssize_t r = read(fd, buffer, DEFAULT_BUFFER_SIZE4096);
75
76 if (!r)
77 break;
78
79 if (r < 0) {
80 switch (errno(*__errno_location ())) {
81 case EAGAIN11:
82 break;
83 case EINTR4:
84 continue;
85 default:
86 return;
87 }
88 }
89
90 coro_yield(conn->coro, CONN_CORO_WANT_READ);
91 }
92
93 /* close(2) will be called when the coroutine yields with CONN_CORO_ABORT */
94}
95
96__attribute__((noreturn)) static int process_request_coro(struct coro *coro,
97 void *data)
98{
99 /* NOTE: This function should not return; coro_yield should be used
100 * instead. This ensures the storage for `strbuf` is alive when the
101 * coroutine ends and lwan_strbuf_free() is called. */
102 struct lwan_connection *conn = data;
103 struct lwan *lwan = conn->thread->lwan;
104 int fd = lwan_connection_get_fd(lwan, conn);
105 enum lwan_request_flags flags = lwan->config.request_flags;
106 struct lwan_strbuf strbuf = LWAN_STRBUF_STATIC_INIT(struct lwan_strbuf) { .buffer = "" };
107 char request_buffer[DEFAULT_BUFFER_SIZE4096];
108 struct lwan_value buffer = {.value = request_buffer, .len = 0};
109 char *next_request = NULL((void*)0);
110 char *header_start[N_HEADER_START64];
111 struct lwan_proxy proxy;
112 const int error_when_n_packets = lwan_calculate_n_packets(DEFAULT_BUFFER_SIZE4096);
113
114 coro_defer(coro, lwan_strbuf_free_defer, &strbuf);
115
116 const size_t init_gen = 1; /* 1 call to coro_defer() */
117 assert(init_gen == coro_deferred_get_generation(coro))((void) sizeof ((init_gen == coro_deferred_get_generation(coro
)) ? 1 : 0), __extension__ ({ if (init_gen == coro_deferred_get_generation
(coro)) ; else __assert_fail ("init_gen == coro_deferred_get_generation(coro)"
, "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 117, __extension__ __PRETTY_FUNCTION__); }))
;
118
119 while (true1) {
120 struct lwan_request_parser_helper helper = {
121 .buffer = &buffer,
122 .next_request = next_request,
123 .error_when_n_packets = error_when_n_packets,
124 .header_start = header_start,
125 };
126 struct lwan_request request = {.conn = conn,
127 .global_response_headers = &lwan->headers,
128 .fd = fd,
129 .response = {.buffer = &strbuf},
130 .flags = flags,
131 .proxy = &proxy,
132 .helper = &helper};
133
134 lwan_process_request(lwan, &request);
135
136 /* Run the deferred instructions now (except those used to initialize
137 * the coroutine), so that if the connection is gracefully closed,
138 * the storage for ``helper'' is still there. */
139 coro_deferred_run(coro, init_gen);
140
141 if (UNLIKELY(!(conn->flags & CONN_IS_KEEP_ALIVE))__builtin_expect(((!(conn->flags & CONN_IS_KEEP_ALIVE)
)), (0))
) {
142 graceful_close(lwan, conn, request_buffer);
143 break;
144 }
145
146 if (next_request && *next_request) {
147 conn->flags |= CONN_CORK;
148
149 if (!(conn->flags & CONN_EVENTS_WRITE))
150 coro_yield(coro, CONN_CORO_WANT_WRITE);
151 } else {
152 conn->flags &= ~CONN_CORK;
153 coro_yield(coro, CONN_CORO_WANT_READ);
154 }
155
156 lwan_strbuf_reset(&strbuf);
157
158 /* Only allow flags from config. */
159 flags = request.flags & (REQUEST_PROXIED | REQUEST_ALLOW_CORS);
160 next_request = helper.next_request;
161 }
162
163 coro_yield(coro, CONN_CORO_ABORT);
164 __builtin_unreachable();
165}
166
167static ALWAYS_INLINEinline __attribute__((always_inline)) uint32_t
168conn_flags_to_epoll_events(enum lwan_connection_flags flags)
169{
170 static const uint32_t map[CONN_EVENTS_MASK + 1] = {
171 [0 /* Suspended (timer or await) */] = EPOLLRDHUPEPOLLRDHUP,
172 [CONN_EVENTS_WRITE] = EPOLLOUTEPOLLOUT | EPOLLRDHUPEPOLLRDHUP,
173 [CONN_EVENTS_READ] = EPOLLINEPOLLIN | EPOLLRDHUPEPOLLRDHUP,
174 [CONN_EVENTS_READ_WRITE] = EPOLLINEPOLLIN | EPOLLOUTEPOLLOUT | EPOLLRDHUPEPOLLRDHUP,
175 };
176
177 return map[flags & CONN_EVENTS_MASK];
178}
179
180static void update_epoll_flags(int fd,
181 struct lwan_connection *conn,
182 int epoll_fd,
183 enum lwan_connection_coro_yield yield_result)
184{
185 static const enum lwan_connection_flags or_mask[CONN_CORO_MAX] = {
186 [CONN_CORO_YIELD] = 0,
187
188 [CONN_CORO_WANT_READ_WRITE] = CONN_EVENTS_READ_WRITE,
189 [CONN_CORO_WANT_READ] = CONN_EVENTS_READ,
190 [CONN_CORO_WANT_WRITE] = CONN_EVENTS_WRITE,
191
192 /* While the coro is suspended, we're not interested in either EPOLLIN
193 * or EPOLLOUT events. We still want to track this fd in epoll, though,
194 * so unset both so that only EPOLLRDHUP (plus the implicitly-set ones)
195 * are set. */
196 [CONN_CORO_SUSPEND_TIMER] = CONN_SUSPENDED_TIMER,
197 [CONN_CORO_SUSPEND_ASYNC_AWAIT] = CONN_SUSPENDED_ASYNC_AWAIT,
198
199 /* Ideally, when suspending a coroutine, the current flags&CONN_EVENTS_MASK
200 * would have to be stored and restored -- however, resuming as if the
201 * client coroutine is interested in a write event always guarantees that
202 * they'll be resumed as they're TCP sockets. There's a good chance that
203 * trying to read from a socket after resuming a coroutine will succeed,
204 * but if it doesn't because read() returns -EAGAIN, the I/O wrappers will
205 * yield with CONN_CORO_WANT_READ anyway. */
206 [CONN_CORO_RESUME] = CONN_EVENTS_WRITE,
207 };
208 static const enum lwan_connection_flags and_mask[CONN_CORO_MAX] = {
209 [CONN_CORO_YIELD] = ~0,
210
211 [CONN_CORO_WANT_READ_WRITE] = ~0,
212 [CONN_CORO_WANT_READ] = ~CONN_EVENTS_WRITE,
213 [CONN_CORO_WANT_WRITE] = ~CONN_EVENTS_READ,
214
215 [CONN_CORO_SUSPEND_TIMER] = ~(CONN_EVENTS_READ_WRITE | CONN_SUSPENDED_ASYNC_AWAIT),
216 [CONN_CORO_SUSPEND_ASYNC_AWAIT] = ~(CONN_EVENTS_READ_WRITE | CONN_SUSPENDED_TIMER),
217 [CONN_CORO_RESUME] = ~CONN_SUSPENDED,
218 };
219 enum lwan_connection_flags prev_flags = conn->flags;
220
221 conn->flags |= or_mask[yield_result];
222 conn->flags &= and_mask[yield_result];
223
224 if (conn->flags == prev_flags)
225 return;
226
227 struct epoll_event event = {
228 .events = conn_flags_to_epoll_events(conn->flags),
229 .data.ptr = conn,
230 };
231
232 if (UNLIKELY(epoll_ctl(epoll_fd, EPOLL_CTL_MOD, fd, &event) < 0)__builtin_expect(((epoll_ctl(epoll_fd, 3, fd, &event) <
0)), (0))
)
233 lwan_status_perror("epoll_ctl")lwan_status_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 233, __FUNCTION__, "epoll_ctl")
;
234}
235
236static void clear_async_await_flag(void *data)
237{
238 struct lwan_connection *async_fd_conn = data;
239
240 async_fd_conn->flags &= ~CONN_ASYNC_AWAIT;
241}
242
243static enum lwan_connection_coro_yield
244resume_async(struct timeout_queue *tq,
245 enum lwan_connection_coro_yield yield_result,
246 int64_t from_coro,
247 struct lwan_connection *conn,
248 int epoll_fd)
249{
250 static const enum lwan_connection_flags to_connection_flags[] = {
251 [CONN_CORO_ASYNC_AWAIT_READ] = CONN_EVENTS_READ,
252 [CONN_CORO_ASYNC_AWAIT_WRITE] = CONN_EVENTS_WRITE,
253 [CONN_CORO_ASYNC_AWAIT_READ_WRITE] = CONN_EVENTS_READ_WRITE,
254 };
255 int await_fd = (int)((uint64_t)from_coro >> 32);
256 enum lwan_connection_flags flags;
257 int op;
258
259 assert(await_fd >= 0)((void) sizeof ((await_fd >= 0) ? 1 : 0), __extension__ ({
if (await_fd >= 0) ; else __assert_fail ("await_fd >= 0"
, "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 259, __extension__ __PRETTY_FUNCTION__); }))
;
260 assert(yield_result >= CONN_CORO_ASYNC_AWAIT_READ &&((void) sizeof ((yield_result >= CONN_CORO_ASYNC_AWAIT_READ
&& yield_result <= CONN_CORO_ASYNC_AWAIT_READ_WRITE
) ? 1 : 0), __extension__ ({ if (yield_result >= CONN_CORO_ASYNC_AWAIT_READ
&& yield_result <= CONN_CORO_ASYNC_AWAIT_READ_WRITE
) ; else __assert_fail ("yield_result >= CONN_CORO_ASYNC_AWAIT_READ && yield_result <= CONN_CORO_ASYNC_AWAIT_READ_WRITE"
, "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 261, __extension__ __PRETTY_FUNCTION__); }))
261 yield_result <= CONN_CORO_ASYNC_AWAIT_READ_WRITE)((void) sizeof ((yield_result >= CONN_CORO_ASYNC_AWAIT_READ
&& yield_result <= CONN_CORO_ASYNC_AWAIT_READ_WRITE
) ? 1 : 0), __extension__ ({ if (yield_result >= CONN_CORO_ASYNC_AWAIT_READ
&& yield_result <= CONN_CORO_ASYNC_AWAIT_READ_WRITE
) ; else __assert_fail ("yield_result >= CONN_CORO_ASYNC_AWAIT_READ && yield_result <= CONN_CORO_ASYNC_AWAIT_READ_WRITE"
, "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 261, __extension__ __PRETTY_FUNCTION__); }))
;
262
263 flags = to_connection_flags[yield_result];
264
265 struct lwan_connection *await_fd_conn = &tq->lwan->conns[await_fd];
266 if (LIKELY(await_fd_conn->flags & CONN_ASYNC_AWAIT)__builtin_expect((!!(await_fd_conn->flags & CONN_ASYNC_AWAIT
)), (1))
) {
267 if (LIKELY((await_fd_conn->flags & CONN_EVENTS_MASK) == flags)__builtin_expect((!!((await_fd_conn->flags & CONN_EVENTS_MASK
) == flags)), (1))
)
268 return CONN_CORO_SUSPEND_ASYNC_AWAIT;
269
270 op = EPOLL_CTL_MOD3;
271 } else {
272 op = EPOLL_CTL_ADD1;
273 flags |= CONN_ASYNC_AWAIT;
274 coro_defer(conn->coro, clear_async_await_flag, await_fd_conn);
275 }
276
277 struct epoll_event event = {.events = conn_flags_to_epoll_events(flags),
278 .data.ptr = conn};
279 if (LIKELY(!epoll_ctl(epoll_fd, op, await_fd, &event))__builtin_expect((!!(!epoll_ctl(epoll_fd, op, await_fd, &
event))), (1))
) {
280 await_fd_conn->flags &= ~CONN_EVENTS_MASK;
281 await_fd_conn->flags |= flags;
282 return CONN_CORO_SUSPEND_ASYNC_AWAIT;
283 }
284
285 return CONN_CORO_ABORT;
286}
287
288static ALWAYS_INLINEinline __attribute__((always_inline)) void resume_coro(struct timeout_queue *tq,
289 struct lwan_connection *conn,
290 int epoll_fd)
291{
292 assert(conn->coro)((void) sizeof ((conn->coro) ? 1 : 0), __extension__ ({ if
(conn->coro) ; else __assert_fail ("conn->coro", "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 292, __extension__ __PRETTY_FUNCTION__); }))
;
293
294 int64_t from_coro = coro_resume(conn->coro);
295 enum lwan_connection_coro_yield yield_result = from_coro & 0xffffffff;
296
297 if (UNLIKELY(yield_result >= CONN_CORO_ASYNC)__builtin_expect(((yield_result >= CONN_CORO_ASYNC)), (0)))
298 yield_result = resume_async(tq, yield_result, from_coro, conn, epoll_fd);
299
300 if (UNLIKELY(yield_result == CONN_CORO_ABORT)__builtin_expect(((yield_result == CONN_CORO_ABORT)), (0)))
301 return timeout_queue_expire(tq, conn);
302
303 return update_epoll_flags(lwan_connection_get_fd(tq->lwan, conn), conn,
304 epoll_fd, yield_result);
305}
306
307static void update_date_cache(struct lwan_thread *thread)
308{
309 time_t now = time(NULL((void*)0));
310
311 lwan_format_rfc_time(now, thread->date.date);
312 lwan_format_rfc_time(now + (time_t)thread->lwan->config.expires,
313 thread->date.expires);
314}
315
316static ALWAYS_INLINEinline __attribute__((always_inline)) void spawn_coro(struct lwan_connection *conn,
317 struct coro_switcher *switcher,
318 struct timeout_queue *tq)
319{
320 struct lwan_thread *t = conn->thread;
321
322 assert(!conn->coro)((void) sizeof ((!conn->coro) ? 1 : 0), __extension__ ({ if
(!conn->coro) ; else __assert_fail ("!conn->coro", "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 322, __extension__ __PRETTY_FUNCTION__); }))
;
323 assert(t)((void) sizeof ((t) ? 1 : 0), __extension__ ({ if (t) ; else __assert_fail
("t", "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 323, __extension__ __PRETTY_FUNCTION__); }))
;
324 assert((uintptr_t)t >= (uintptr_t)tq->lwan->thread.threads)((void) sizeof (((uintptr_t)t >= (uintptr_t)tq->lwan->
thread.threads) ? 1 : 0), __extension__ ({ if ((uintptr_t)t >=
(uintptr_t)tq->lwan->thread.threads) ; else __assert_fail
("(uintptr_t)t >= (uintptr_t)tq->lwan->thread.threads"
, "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 324, __extension__ __PRETTY_FUNCTION__); }))
;
325 assert((uintptr_t)t <((void) sizeof (((uintptr_t)t < (uintptr_t)(tq->lwan->
thread.threads + tq->lwan->thread.count)) ? 1 : 0), __extension__
({ if ((uintptr_t)t < (uintptr_t)(tq->lwan->thread.
threads + tq->lwan->thread.count)) ; else __assert_fail
("(uintptr_t)t < (uintptr_t)(tq->lwan->thread.threads + tq->lwan->thread.count)"
, "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 326, __extension__ __PRETTY_FUNCTION__); }))
326 (uintptr_t)(tq->lwan->thread.threads + tq->lwan->thread.count))((void) sizeof (((uintptr_t)t < (uintptr_t)(tq->lwan->
thread.threads + tq->lwan->thread.count)) ? 1 : 0), __extension__
({ if ((uintptr_t)t < (uintptr_t)(tq->lwan->thread.
threads + tq->lwan->thread.count)) ; else __assert_fail
("(uintptr_t)t < (uintptr_t)(tq->lwan->thread.threads + tq->lwan->thread.count)"
, "/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 326, __extension__ __PRETTY_FUNCTION__); }))
;
327
328 *conn = (struct lwan_connection) {
329 .coro = coro_new(switcher, process_request_coro, conn),
330 .flags = CONN_EVENTS_READ,
331 .time_to_expire = tq->current_time + tq->move_to_last_bump,
332 .thread = t,
333 };
334 if (UNLIKELY(!conn->coro)__builtin_expect(((!conn->coro)), (0))) {
335 /* FIXME: send a "busy" response to this client? we don't have a coroutine
336 * at this point, can't use lwan_send() here */
337 lwan_status_error("Could not create coroutine, dropping connection")lwan_status_error_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 337, __FUNCTION__, "Could not create coroutine, dropping connection"
)
;
338
339 conn->flags = 0;
340
341 int fd = lwan_connection_get_fd(tq->lwan, conn);
342 shutdown(fd, SHUT_RDWRSHUT_RDWR);
343 close(fd);
344
345 return;
346 }
347
348 timeout_queue_insert(tq, conn);
349}
350
351static void accept_nudge(int pipe_fd,
352 struct lwan_thread *t,
353 struct lwan_connection *conns,
354 struct timeout_queue *tq,
355 struct coro_switcher *switcher,
356 int epoll_fd)
357{
358 uint64_t event;
359 int new_fd;
360
361 /* Errors are ignored here as pipe_fd serves just as a way to wake the
362 * thread from epoll_wait(). It's fine to consume the queue at this
363 * point, regardless of the error type. */
364 (void)read(pipe_fd, &event, sizeof(event));
365
366 while (spsc_queue_pop(&t->pending_fds, &new_fd)) {
367 struct lwan_connection *conn = &conns[new_fd];
368 struct epoll_event ev = {
369 .data.ptr = conn,
370 .events = conn_flags_to_epoll_events(CONN_EVENTS_READ),
371 };
372
373 if (LIKELY(!epoll_ctl(epoll_fd, EPOLL_CTL_ADD, new_fd, &ev))__builtin_expect((!!(!epoll_ctl(epoll_fd, 1, new_fd, &ev)
)), (1))
)
374 spawn_coro(conn, switcher, tq);
375 }
376
377 timeouts_add(t->wheel, &tq->timeout, 1000);
378}
379
380static bool_Bool process_pending_timers(struct timeout_queue *tq,
381 struct lwan_thread *t,
382 int epoll_fd)
383{
384 struct timeout *timeout;
385 bool_Bool should_expire_timers = false0;
386
387 while ((timeout = timeouts_get(t->wheel))) {
388 struct lwan_request *request;
389
390 if (timeout == &tq->timeout) {
391 should_expire_timers = true1;
392 continue;
393 }
394
395 request = container_of(timeout, struct lwan_request, timeout)((struct lwan_request *) ((char *)(timeout) - __builtin_offsetof
(struct lwan_request, timeout)) + ((typeof(*(timeout)) *)0 !=
(typeof(((struct lwan_request *)0)->timeout) *)0))
;
396
397 update_epoll_flags(request->fd, request->conn, epoll_fd,
398 CONN_CORO_RESUME);
399 }
400
401 if (should_expire_timers) {
402 timeout_queue_expire_waiting(tq);
403
404 /* tq timeout expires every 1000ms if there are connections, so
405 * update the date cache at this point as well. */
406 update_date_cache(t);
407
408 if (!timeout_queue_empty(tq)) {
409 timeouts_add(t->wheel, &tq->timeout, 1000);
410 return true1;
411 }
412
413 timeouts_del(t->wheel, &tq->timeout);
414 }
415
416 return false0;
417}
418
419static int
420turn_timer_wheel(struct timeout_queue *tq, struct lwan_thread *t, int epoll_fd)
421{
422 timeout_t wheel_timeout;
423 struct timespec now;
424
425 if (UNLIKELY(clock_gettime(monotonic_clock_id, &now) < 0)__builtin_expect(((clock_gettime(monotonic_clock_id, &now
) < 0)), (0))
)
426 lwan_status_critical("Could not get monotonic time")lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 426, __FUNCTION__, "Could not get monotonic time")
;
427
428 timeouts_update(t->wheel,
429 (timeout_t)(now.tv_sec * 1000 + now.tv_nsec / 1000000));
430
431 wheel_timeout = timeouts_timeout(t->wheel);
432 if (UNLIKELY((int64_t)wheel_timeout < 0)__builtin_expect((((int64_t)wheel_timeout < 0)), (0)))
433 goto infinite_timeout;
434
435 if (wheel_timeout == 0) {
436 if (!process_pending_timers(tq, t, epoll_fd))
437 goto infinite_timeout;
438
439 wheel_timeout = timeouts_timeout(t->wheel);
440 if (wheel_timeout == 0)
441 goto infinite_timeout;
442 }
443
444 return (int)wheel_timeout;
445
446infinite_timeout:
447 return -1;
448}
449
450static void *thread_io_loop(void *data)
451{
452 struct lwan_thread *t = data;
453 int epoll_fd = t->epoll_fd;
454 const int read_pipe_fd = t->pipe_fd[0];
455 const int max_events = LWAN_MIN((int)t->lwan->thread.max_fd, 1024)({ const __typeof__(((int)t->lwan->thread.max_fd) + 0) lwan_tmp_id10
= ((int)t->lwan->thread.max_fd); const __typeof__((1024
) + 0) lwan_tmp_id11 = (1024); lwan_tmp_id10 > lwan_tmp_id11
? lwan_tmp_id11 : lwan_tmp_id10; })
;
456 struct lwan *lwan = t->lwan;
457 struct epoll_event *events;
458 struct coro_switcher switcher;
459 struct timeout_queue tq;
460
461 lwan_status_debug("Worker thread #%zd starting",lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 462, __FUNCTION__, "Worker thread #%zd starting", t - t->
lwan->thread.threads + 1)
462 t - t->lwan->thread.threads + 1)lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 462, __FUNCTION__, "Worker thread #%zd starting", t - t->
lwan->thread.threads + 1)
;
463 lwan_set_thread_name("worker");
464
465 events = calloc((size_t)max_events, sizeof(*events));
466 if (UNLIKELY(!events)__builtin_expect(((!events)), (0)))
467 lwan_status_critical("Could not allocate memory for events")lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 467, __FUNCTION__, "Could not allocate memory for events")
;
468
469 update_date_cache(t);
470
471 timeout_queue_init(&tq, lwan);
472
473 pthread_barrier_wait(&lwan->thread.barrier);
474
475 for (;;) {
476 int timeout = turn_timer_wheel(&tq, t, epoll_fd);
477 int n_fds = epoll_wait(epoll_fd, events, max_events, timeout);
478
479 if (UNLIKELY(n_fds < 0)__builtin_expect(((n_fds < 0)), (0))) {
480 if (errno(*__errno_location ()) == EBADF9 || errno(*__errno_location ()) == EINVAL22)
481 break;
482 continue;
483 }
484
485 for (struct epoll_event *event = events; n_fds--; event++) {
486 struct lwan_connection *conn;
487
488 if (UNLIKELY(!event->data.ptr)__builtin_expect(((!event->data.ptr)), (0))) {
489 accept_nudge(read_pipe_fd, t, lwan->conns, &tq, &switcher,
490 epoll_fd);
491 continue;
492 }
493
494 conn = event->data.ptr;
495
496 if (UNLIKELY(event->events & (EPOLLRDHUP | EPOLLHUP))__builtin_expect(((event->events & (EPOLLRDHUP | EPOLLHUP
))), (0))
) {
497 timeout_queue_expire(&tq, conn);
498 continue;
499 }
500
501 resume_coro(&tq, conn, epoll_fd);
502 timeout_queue_move_to_last(&tq, conn);
503 }
504 }
505
506 pthread_barrier_wait(&lwan->thread.barrier);
507
508 timeout_queue_expire_all(&tq);
509 free(events);
510
511 return NULL((void*)0);
512}
513
514static void create_thread(struct lwan *l, struct lwan_thread *thread,
515 const size_t n_queue_fds)
516{
517 int ignore;
518 pthread_attr_t attr;
519
520 memset(thread, 0, sizeof(*thread));
521 thread->lwan = l;
522
523 thread->wheel = timeouts_open(&ignore);
524 if (!thread->wheel)
525 lwan_status_critical("Could not create timer wheel")lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 525, __FUNCTION__, "Could not create timer wheel")
;
526
527 if ((thread->epoll_fd = epoll_create1(EPOLL_CLOEXECEPOLL_CLOEXEC)) < 0)
528 lwan_status_critical_perror("epoll_create")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 528, __FUNCTION__, "epoll_create")
;
529
530 if (pthread_attr_init(&attr))
531 lwan_status_critical_perror("pthread_attr_init")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 531, __FUNCTION__, "pthread_attr_init")
;
532
533 if (pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEMPTHREAD_SCOPE_SYSTEM))
534 lwan_status_critical_perror("pthread_attr_setscope")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 534, __FUNCTION__, "pthread_attr_setscope")
;
535
536 if (pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLEPTHREAD_CREATE_JOINABLE))
537 lwan_status_critical_perror("pthread_attr_setdetachstate")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 537, __FUNCTION__, "pthread_attr_setdetachstate")
;
538
539#if defined(HAVE_EVENTFD)
540 int efd = eventfd(0, EFD_NONBLOCKEFD_NONBLOCK | EFD_SEMAPHOREEFD_SEMAPHORE | EFD_CLOEXECEFD_CLOEXEC);
541 if (efd < 0)
542 lwan_status_critical_perror("eventfd")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 542, __FUNCTION__, "eventfd")
;
543
544 thread->pipe_fd[0] = thread->pipe_fd[1] = efd;
545#else
546 if (pipe2(thread->pipe_fd, O_NONBLOCK04000 | O_CLOEXEC02000000) < 0)
547 lwan_status_critical_perror("pipe")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 547, __FUNCTION__, "pipe")
;
548#endif
549
550 struct epoll_event event = { .events = EPOLLINEPOLLIN, .data.ptr = NULL((void*)0) };
551 if (epoll_ctl(thread->epoll_fd, EPOLL_CTL_ADD1, thread->pipe_fd[0], &event) < 0)
552 lwan_status_critical_perror("epoll_ctl")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 552, __FUNCTION__, "epoll_ctl")
;
553
554 if (pthread_create(&thread->self, &attr, thread_io_loop, thread))
555 lwan_status_critical_perror("pthread_create")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 555, __FUNCTION__, "pthread_create")
;
556
557 if (pthread_attr_destroy(&attr))
558 lwan_status_critical_perror("pthread_attr_destroy")lwan_status_critical_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 558, __FUNCTION__, "pthread_attr_destroy")
;
559
560 if (spsc_queue_init(&thread->pending_fds, n_queue_fds) < 0) {
561 lwan_status_critical("Could not initialize pending fd "lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 562, __FUNCTION__, "Could not initialize pending fd " "queue width %zu elements"
, n_queue_fds)
562 "queue width %zu elements", n_queue_fds)lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 562, __FUNCTION__, "Could not initialize pending fd " "queue width %zu elements"
, n_queue_fds)
;
563 }
564}
565
566void lwan_thread_nudge(struct lwan_thread *t)
567{
568 uint64_t event = 1;
569
570 if (UNLIKELY(write(t->pipe_fd[1], &event, sizeof(event)) < 0)__builtin_expect(((write(t->pipe_fd[1], &event, sizeof
(event)) < 0)), (0))
)
571 lwan_status_perror("write")lwan_status_perror_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 571, __FUNCTION__, "write")
;
572}
573
574void lwan_thread_add_client(struct lwan_thread *t, int fd)
575{
576 for (int i = 0; i < 10; i++) {
577 bool_Bool pushed = spsc_queue_push(&t->pending_fds, fd);
578
579 if (LIKELY(pushed)__builtin_expect((!!(pushed)), (1)))
580 return;
581
582 /* Queue is full; nudge the thread to consume it. */
583 lwan_thread_nudge(t);
584 }
585
586 lwan_status_error("Dropping connection %d", fd)lwan_status_error_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 586, __FUNCTION__, "Dropping connection %d", fd)
;
587 /* FIXME: send "busy" response now, even without receiving request? */
588 close(fd);
589}
590
591#if defined(__linux__1) && defined(__x86_64__1)
592static bool_Bool read_cpu_topology(struct lwan *l, uint32_t siblings[])
593{
594 char path[PATH_MAX4096];
595
596 for (uint32_t i = 0; i < l->available_cpus; i++)
597 siblings[i] = 0xbebacafe;
598
599 for (unsigned int i = 0; i < l->available_cpus; i++) {
600 FILE *sib;
601 uint32_t id, sibling;
602 char separator;
603
604 snprintf(path, sizeof(path),
605 "/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list",
606 i);
607
608 sib = fopen(path, "re");
609 if (!sib) {
610 lwan_status_warning("Could not open `%s` to determine CPU topology",lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 611, __FUNCTION__, "Could not open `%s` to determine CPU topology"
, path)
611 path)lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 611, __FUNCTION__, "Could not open `%s` to determine CPU topology"
, path)
;
612 return false0;
613 }
614
615 switch (fscanf(sib, "%u%c%u", &id, &separator, &sibling)) {
616 case 2: /* No SMT */
617 siblings[i] = id;
618 break;
619 case 3: /* SMT */
620 if (!(separator == ',' || separator == '-')) {
621 lwan_status_critical("Expecting either ',' or '-' for sibling separator")lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 621, __FUNCTION__, "Expecting either ',' or '-' for sibling separator"
)
;
622 __builtin_unreachable();
623 }
624
625 siblings[i] = sibling;
626 break;
627 default:
628 lwan_status_critical("%s has invalid format", path)lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 628, __FUNCTION__, "%s has invalid format", path)
;
629 __builtin_unreachable();
630 }
631
632 fclose(sib);
633 }
634
635 /* Perform a sanity check here, as some systems seem to filter out the
636 * result of sysconf() to obtain the number of configured and online
637 * CPUs but don't bother changing what's available through sysfs as far
638 * as the CPU topology information goes. It's better to fall back to a
639 * possibly non-optimal setup than just crash during startup while
640 * trying to perform an out-of-bounds array access. */
641 for (unsigned int i = 0; i < l->available_cpus; i++) {
642 if (siblings[i] == 0xbebacafe) {
643 lwan_status_warning("Could not determine sibling for CPU %d", i)lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 643, __FUNCTION__, "Could not determine sibling for CPU %d"
, i)
;
644 return false0;
645 }
646
647 if (siblings[i] >= l->available_cpus) {
648 lwan_status_warning("CPU information topology says CPU %d exists, "lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 651, __FUNCTION__, "CPU information topology says CPU %d exists, "
"but max available CPUs is %d (online CPUs: %d). " "Is Lwan running in a (broken) container?"
, siblings[i], l->available_cpus, l->online_cpus)
649 "but max available CPUs is %d (online CPUs: %d). "lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 651, __FUNCTION__, "CPU information topology says CPU %d exists, "
"but max available CPUs is %d (online CPUs: %d). " "Is Lwan running in a (broken) container?"
, siblings[i], l->available_cpus, l->online_cpus)
650 "Is Lwan running in a (broken) container?",lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 651, __FUNCTION__, "CPU information topology says CPU %d exists, "
"but max available CPUs is %d (online CPUs: %d). " "Is Lwan running in a (broken) container?"
, siblings[i], l->available_cpus, l->online_cpus)
651 siblings[i], l->available_cpus, l->online_cpus)lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 651, __FUNCTION__, "CPU information topology says CPU %d exists, "
"but max available CPUs is %d (online CPUs: %d). " "Is Lwan running in a (broken) container?"
, siblings[i], l->available_cpus, l->online_cpus)
;
652 return false0;
653 }
654 }
655
656 return true1;
657}
658
659static void
660siblings_to_schedtbl(struct lwan *l, uint32_t siblings[], uint32_t schedtbl[])
661{
662 int *seen = alloca(l->available_cpus * sizeof(int))__builtin_alloca (l->available_cpus * sizeof(int));
663 unsigned int n_schedtbl = 0;
664
665 for (uint32_t i = 0; i < l->available_cpus; i++)
666 seen[i] = -1;
667
668 for (uint32_t i = 0; i < l->available_cpus; i++) {
669 if (seen[siblings[i]] < 0) {
670 seen[siblings[i]] = (int)i;
671 } else {
672 schedtbl[n_schedtbl++] = (uint32_t)seen[siblings[i]];
673 schedtbl[n_schedtbl++] = i;
674 }
675 }
676
677 if (n_schedtbl != l->available_cpus)
678 memcpy(schedtbl, seen, l->available_cpus * sizeof(int));
679}
680
681static bool_Bool
682topology_to_schedtbl(struct lwan *l, uint32_t schedtbl[], uint32_t n_threads)
683{
684 uint32_t *siblings = alloca(l->available_cpus * sizeof(uint32_t))__builtin_alloca (l->available_cpus * sizeof(uint32_t));
685
686 if (read_cpu_topology(l, siblings)) {
11
Assuming the condition is false
12
Taking false branch
687 uint32_t *affinity = alloca(l->available_cpus * sizeof(uint32_t))__builtin_alloca (l->available_cpus * sizeof(uint32_t));
688
689 siblings_to_schedtbl(l, siblings, affinity);
690
691 for (uint32_t i = 0; i < n_threads; i++)
692 schedtbl[i] = affinity[i % l->available_cpus];
693 return true1;
694 }
695
696 for (uint32_t i = 0; i < n_threads; i++)
13
Assuming 'i' is >= 'n_threads'
14
Loop condition is false. Execution continues on line 698
697 schedtbl[i] = (i / 2) % l->thread.count;
698 return false0;
15
Returning without writing to '*schedtbl'
699}
700
701static void
702adjust_threads_affinity(struct lwan *l, uint32_t *schedtbl, uint32_t mask)
703{
704 for (uint32_t i = 0; i < l->thread.count; i++) {
705 cpu_set_t set;
706
707 CPU_ZERO(&set)do __builtin_memset (&set, '\0', sizeof (cpu_set_t)); while
(0)
;
708 CPU_SET(schedtbl[i & mask], &set)(__extension__ ({ size_t __cpu = (schedtbl[i & mask]); __cpu
/ 8 < (sizeof (cpu_set_t)) ? (((__cpu_mask *) ((&set)
->__bits))[((__cpu) / (8 * sizeof (__cpu_mask)))] |= ((__cpu_mask
) 1 << ((__cpu) % (8 * sizeof (__cpu_mask))))) : 0; }))
;
709
710 if (pthread_setaffinity_np(l->thread.threads[i].self, sizeof(set),
711 &set))
712 lwan_status_warning("Could not set affinity for thread %d", i)lwan_status_warning_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 712, __FUNCTION__, "Could not set affinity for thread %d", i
)
;
713 }
714}
715#elif defined(__x86_64__1)
716static bool_Bool
717topology_to_schedtbl(struct lwan *l, uint32_t schedtbl[], uint32_t n_threads)
718{
719 for (uint32_t i = 0; i < n_threads; i++)
720 schedtbl[i] = (i / 2) % l->thread.count;
721 return false0;
722}
723
724static void
725adjust_threads_affinity(struct lwan *l, uint32_t *schedtbl, uint32_t n)
726{
727}
728#endif
729
730void lwan_thread_init(struct lwan *l)
731{
732 if (pthread_barrier_init(&l->thread.barrier, NULL((void*)0),
1
Assuming the condition is false
2
Taking false branch
733 (unsigned)l->thread.count + 1))
734 lwan_status_critical("Could not create barrier")lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 734, __FUNCTION__, "Could not create barrier")
;
735
736 lwan_status_debug("Initializing threads")lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 736, __FUNCTION__, "Initializing threads")
;
737
738 l->thread.threads =
739 calloc((size_t)l->thread.count, sizeof(struct lwan_thread));
740 if (!l->thread.threads)
3
Assuming field 'threads' is non-null
4
Taking false branch
741 lwan_status_critical("Could not allocate memory for threads")lwan_status_critical_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 741, __FUNCTION__, "Could not allocate memory for threads")
;
742
743 const size_t n_queue_fds = LWAN_MIN(l->thread.max_fd / l->thread.count,({ const __typeof__((l->thread.max_fd / l->thread.count
) + 0) lwan_tmp_id12 = (l->thread.max_fd / l->thread.count
); const __typeof__(((size_t)(2 * lwan_socket_get_backlog_size
())) + 0) lwan_tmp_id13 = ((size_t)(2 * lwan_socket_get_backlog_size
())); lwan_tmp_id12 > lwan_tmp_id13 ? lwan_tmp_id13 : lwan_tmp_id12
; })
5
Assuming 'lwan_tmp_id4' is <= 'lwan_tmp_id5'
6
'?' condition is false
744 (size_t)(2 * lwan_socket_get_backlog_size()))({ const __typeof__((l->thread.max_fd / l->thread.count
) + 0) lwan_tmp_id12 = (l->thread.max_fd / l->thread.count
); const __typeof__(((size_t)(2 * lwan_socket_get_backlog_size
())) + 0) lwan_tmp_id13 = ((size_t)(2 * lwan_socket_get_backlog_size
())); lwan_tmp_id12 > lwan_tmp_id13 ? lwan_tmp_id13 : lwan_tmp_id12
; })
;
745 lwan_status_debug("Pending client file descriptor queue has %zu items", n_queue_fds)lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 745, __FUNCTION__, "Pending client file descriptor queue has %zu items"
, n_queue_fds)
;
746 for (unsigned int i = 0; i
6.1
'i' is < field 'count'
< l->thread.count
; i++)
7
Loop condition is true. Entering loop body
8
Assuming 'i' is >= field 'count'
9
Loop condition is false. Execution continues on line 749
747 create_thread(l, &l->thread.threads[i], n_queue_fds);
748
749 const unsigned int total_conns = l->thread.max_fd * l->thread.count;
750#ifdef __x86_64__1
751 static_assert(sizeof(struct lwan_connection) == 32,extern int (*__Static_assert_function (void)) [!!sizeof (struct
{ int __error_if_negative: (sizeof(struct lwan_connection) ==
32) ? 2 : -1; })]
752 "Two connections per cache line")extern int (*__Static_assert_function (void)) [!!sizeof (struct
{ int __error_if_negative: (sizeof(struct lwan_connection) ==
32) ? 2 : -1; })]
;
753
754 lwan_status_debug("%d CPUs of %d are online. "lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 756, __FUNCTION__, "%d CPUs of %d are online. " "Reading topology to pre-schedule clients"
, l->online_cpus, l->available_cpus)
755 "Reading topology to pre-schedule clients",lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 756, __FUNCTION__, "%d CPUs of %d are online. " "Reading topology to pre-schedule clients"
, l->online_cpus, l->available_cpus)
756 l->online_cpus, l->available_cpus)lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 756, __FUNCTION__, "%d CPUs of %d are online. " "Reading topology to pre-schedule clients"
, l->online_cpus, l->available_cpus)
;
757
758 /*
759 * Pre-schedule each file descriptor, to reduce some operations in the
760 * fast path.
761 *
762 * Since struct lwan_connection is guaranteed to be 32-byte long, two of
763 * them can fill up a cache line. Assume siblings share cache lines and
764 * use the CPU topology to group two connections per cache line in such
765 * a way that false sharing is avoided.
766 */
767 uint32_t n_threads = (uint32_t)lwan_nextpow2((size_t)((l->thread.count - 1) * 2));
768 uint32_t *schedtbl = alloca(n_threads * sizeof(uint32_t))__builtin_alloca (n_threads * sizeof(uint32_t));
769
770 bool_Bool adj_affinity = topology_to_schedtbl(l, schedtbl, n_threads);
10
Calling 'topology_to_schedtbl'
16
Returning from 'topology_to_schedtbl'
771
772 n_threads--; /* Transform count into mask for AND below */
773
774 if (adj_affinity
16.1
'adj_affinity' is false
)
17
Taking false branch
775 adjust_threads_affinity(l, schedtbl, n_threads);
776
777 for (unsigned int i = 0; i < total_conns; i++)
18
Assuming 'i' is < 'total_conns'
19
Loop condition is true. Entering loop body
778 l->conns[i].thread = &l->thread.threads[schedtbl[i & n_threads]];
20
Array subscript is undefined
779#else
780 for (unsigned int i = 0; i < total_conns; i++)
781 l->conns[i].thread = &l->thread.threads[i % l->thread.count];
782#endif
783
784 pthread_barrier_wait(&l->thread.barrier);
785
786 lwan_status_debug("Worker threads created and ready to serve")lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 786, __FUNCTION__, "Worker threads created and ready to serve"
)
;
787}
788
789void lwan_thread_shutdown(struct lwan *l)
790{
791 lwan_status_debug("Shutting down threads")lwan_status_debug_debug("/home/buildbot/lwan-worker/clang-analyze/build/src/lib/lwan-thread.c"
, 791, __FUNCTION__, "Shutting down threads")
;
792
793 for (unsigned int i = 0; i < l->thread.count; i++) {
794 struct lwan_thread *t = &l->thread.threads[i];
795
796 close(t->epoll_fd);
797 lwan_thread_nudge(t);
798 }
799
800 pthread_barrier_wait(&l->thread.barrier);
801 pthread_barrier_destroy(&l->thread.barrier);
802
803 for (unsigned int i = 0; i < l->thread.count; i++) {
804 struct lwan_thread *t = &l->thread.threads[i];
805
806 close(t->pipe_fd[0]);
807#if !defined(HAVE_EVENTFD)
808 close(t->pipe_fd[1]);
809#endif
810
811 pthread_join(l->thread.threads[i].self, NULL((void*)0));
812 spsc_queue_free(&t->pending_fds);
813 timeouts_close(t->wheel);
814 }
815
816 free(l->thread.threads);
817}