/* Test that iconv works in a multi-threaded program. Copyright (C) 2017-2022 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ /* This test runs several worker threads that perform the following three steps in staggered synchronization with each other: 1. initialization (iconv_open) 2. conversion (iconv) 3. cleanup (iconv_close) Having several threads synchronously (using pthread_barrier_*) perform these routines exercises iconv code that handles concurrent attempts to initialize and/or read global iconv state (namely configuration). */ #include <iconv.h> #include <stdio.h> #include <string.h> #include <support/support.h> #include <support/xthread.h> #include <support/check.h> #define TCOUNT 16 _Static_assert (TCOUNT %2 == 0, "thread count must be even, since we need two groups."); #define CONV_INPUT "Hello, iconv!" pthread_barrier_t sync; pthread_barrier_t sync_half_pool; /* Execute iconv_open, iconv and iconv_close in a synchronized way in conjunction with other sibling worker threads. If any step fails, print an error to stdout and return NULL to the main thread to indicate the error. */ static void * worker (void * arg) { long int tidx = (long int) arg; iconv_t cd; char ascii[] = CONV_INPUT; char *inbufpos = ascii; size_t inbytesleft = sizeof (CONV_INPUT); char *utf8 = xcalloc (sizeof (CONV_INPUT), 1); char *outbufpos = utf8; size_t outbytesleft = sizeof (CONV_INPUT); if (tidx < TCOUNT/2) /* The first half of the worker thread pool synchronize together here, then call iconv_open immediately after. */ xpthread_barrier_wait (&sync_half_pool); else /* The second half wait for the first half to finish iconv_open and continue to the next barrier (before the call to iconv below). */ xpthread_barrier_wait (&sync); /* The above block of code staggers all subsequent pthread_barrier_wait calls in a way that ensures a high chance of encountering these combinations of concurrent iconv usage: 1) concurrent calls to iconv_open, 2) concurrent calls to iconv_open *and* iconv, 3) concurrent calls to iconv, 4) concurrent calls to iconv *and* iconv_close, 5) concurrent calls to iconv_close. */ cd = iconv_open ("UTF8", "ASCII"); TEST_VERIFY_EXIT (cd != (iconv_t) -1); xpthread_barrier_wait (&sync); TEST_VERIFY_EXIT (iconv (cd, &inbufpos, &inbytesleft, &outbufpos, &outbytesleft) != (size_t) -1); *outbufpos = '\0'; xpthread_barrier_wait (&sync); TEST_VERIFY_EXIT (iconv_close (cd) == 0); /* The next conditional barrier wait is needed because we staggered the threads into two groups in the beginning and at this point, the second half of worker threads are waiting for the first half to finish iconv_close before they can executing the same: */ if (tidx < TCOUNT/2) xpthread_barrier_wait (&sync); if (strncmp (utf8, CONV_INPUT, sizeof CONV_INPUT)) { printf ("FAIL: thread %lx: invalid conversion output from iconv\n", tidx); pthread_exit ((void *) (long int) 1); } pthread_exit (NULL); } static int do_test (void) { pthread_t thread[TCOUNT]; void * worker_output; int i; xpthread_barrier_init (&sync, NULL, TCOUNT); xpthread_barrier_init (&sync_half_pool, NULL, TCOUNT/2); for (i = 0; i < TCOUNT; i++) thread[i] = xpthread_create (NULL, worker, (void *) (long int) i); for (i = 0; i < TCOUNT; i++) { worker_output = xpthread_join (thread[i]); TEST_VERIFY_EXIT (worker_output == NULL); } xpthread_barrier_destroy (&sync); xpthread_barrier_destroy (&sync_half_pool); return 0; } #include <support/test-driver.c>