@@ -43,7 +43,7 @@ CFLAGS-charmap.c = -DCHARMAP_PATH='"$(i18ndir)/charmaps"' \
CFLAGS-linereader.c = -DNO_TRANSLITERATION
CFLAGS-simple-hash.c = -I../locale
-tests = tst-iconv1 tst-iconv2 tst-iconv3 tst-iconv4 tst-iconv5 tst-iconv6
+tests = tst-iconv1 tst-iconv2 tst-iconv3 tst-iconv4 tst-iconv5 tst-iconv6 tst-iconv_mt
others = iconv_prog iconvconfig
install-others-programs = $(inst_bindir)/iconv
@@ -67,6 +67,8 @@ endif
$(objpfx)gconv-modules: test-gconv-modules
cp $< $@
+$(objpfx)tst-iconv_mt: $(shared-thread-library)
+
ifeq (yes,$(build-shared))
tests += tst-gconv-init-failure
modules-names += tst-gconv-init-failure-mod
@@ -423,115 +423,107 @@ read_conf_file (const char *filename, const char *directory, size_t dir_len,
void
__gconv_get_path (void)
{
- struct path_elem *result;
- __libc_lock_define_initialized (static, lock);
-
- __libc_lock_lock (lock);
-
- /* Make sure there wasn't a second thread doing it already. */
- result = (struct path_elem *) __gconv_path_elem;
- if (result == NULL)
+ /* Make sure we haven't done it already. */
+ assert (__gconv_path_elem == NULL);
+
+ /* Determine the complete path first. */
+ char *gconv_path;
+ size_t gconv_path_len;
+ char *elem;
+ char *oldp;
+ char *cp;
+ int nelems;
+ char *cwd;
+ size_t cwdlen;
+
+ if (__gconv_path_envvar == NULL)
{
- /* Determine the complete path first. */
- char *gconv_path;
- size_t gconv_path_len;
- char *elem;
- char *oldp;
- char *cp;
- int nelems;
- char *cwd;
- size_t cwdlen;
-
- if (__gconv_path_envvar == NULL)
- {
- /* No user-defined path. Make a modifiable copy of the
- default path. */
- gconv_path = strdupa (default_gconv_path);
- gconv_path_len = sizeof (default_gconv_path);
- cwd = NULL;
- cwdlen = 0;
- }
- else
- {
- /* Append the default path to the user-defined path. */
- size_t user_len = strlen (__gconv_path_envvar);
-
- gconv_path_len = user_len + 1 + sizeof (default_gconv_path);
- gconv_path = alloca (gconv_path_len);
- __mempcpy (__mempcpy (__mempcpy (gconv_path, __gconv_path_envvar,
- user_len),
- ":", 1),
- default_gconv_path, sizeof (default_gconv_path));
- cwd = __getcwd (NULL, 0);
- cwdlen = __glibc_unlikely (cwd == NULL) ? 0 : strlen (cwd);
- }
- assert (default_gconv_path[0] == '/');
-
- /* In a first pass we calculate the number of elements. */
- oldp = NULL;
- cp = strchr (gconv_path, ':');
- nelems = 1;
- while (cp != NULL)
- {
- if (cp != oldp + 1)
- ++nelems;
- oldp = cp;
- cp = strchr (cp + 1, ':');
- }
-
- /* Allocate the memory for the result. */
- result = (struct path_elem *) malloc ((nelems + 1)
- * sizeof (struct path_elem)
- + gconv_path_len + nelems
- + (nelems - 1) * (cwdlen + 1));
- if (result != NULL)
- {
- char *strspace = (char *) &result[nelems + 1];
- int n = 0;
-
- /* Separate the individual parts. */
- __gconv_max_path_elem_len = 0;
- elem = __strtok_r (gconv_path, ":", &gconv_path);
- assert (elem != NULL);
- do
- {
- result[n].name = strspace;
- if (elem[0] != '/')
- {
- assert (cwd != NULL);
- strspace = __mempcpy (strspace, cwd, cwdlen);
- *strspace++ = '/';
- }
- strspace = __stpcpy (strspace, elem);
- if (strspace[-1] != '/')
- *strspace++ = '/';
-
- result[n].len = strspace - result[n].name;
- if (result[n].len > __gconv_max_path_elem_len)
- __gconv_max_path_elem_len = result[n].len;
-
- *strspace++ = '\0';
- ++n;
- }
- while ((elem = __strtok_r (NULL, ":", &gconv_path)) != NULL);
-
- result[n].name = NULL;
- result[n].len = 0;
- }
+ /* No user-defined path. Make a modifiable copy of the
+ default path. */
+ gconv_path = strdupa (default_gconv_path);
+ gconv_path_len = sizeof (default_gconv_path);
+ cwd = NULL;
+ cwdlen = 0;
+ }
+ else
+ {
+ /* Append the default path to the user-defined path. */
+ size_t user_len = strlen (__gconv_path_envvar);
+
+ gconv_path_len = user_len + 1 + sizeof (default_gconv_path);
+ gconv_path = alloca (gconv_path_len);
+ __mempcpy (__mempcpy (__mempcpy (gconv_path, __gconv_path_envvar,
+ user_len),
+ ":", 1),
+ default_gconv_path, sizeof (default_gconv_path));
+ cwd = __getcwd (NULL, 0);
+ cwdlen = __glibc_unlikely (cwd == NULL) ? 0 : strlen (cwd);
+ }
+ assert (default_gconv_path[0] == '/');
- __gconv_path_elem = result ?: (struct path_elem *) &empty_path_elem;
+ /* In a first pass we calculate the number of elements. */
+ oldp = NULL;
+ cp = strchr (gconv_path, ':');
+ nelems = 1;
+ while (cp != NULL)
+ {
+ if (cp != oldp + 1)
+ ++nelems;
+ oldp = cp;
+ cp = strchr (cp + 1, ':');
+ }
- free (cwd);
+ /* Allocate the memory for the result. */
+ __gconv_path_elem = malloc ((nelems + 1)
+ * sizeof (struct path_elem)
+ + gconv_path_len + nelems
+ + (nelems - 1) * (cwdlen + 1));
+ if (__gconv_path_elem != NULL)
+ {
+ char *strspace = (char *) &__gconv_path_elem[nelems + 1];
+ int n = 0;
+
+ /* Separate the individual parts. */
+ __gconv_max_path_elem_len = 0;
+ elem = __strtok_r (gconv_path, ":", &gconv_path);
+ assert (elem != NULL);
+ do
+ {
+ __gconv_path_elem[n].name = strspace;
+ if (elem[0] != '/')
+ {
+ assert (cwd != NULL);
+ strspace = __mempcpy (strspace, cwd, cwdlen);
+ *strspace++ = '/';
+ }
+ strspace = __stpcpy (strspace, elem);
+ if (strspace[-1] != '/')
+ *strspace++ = '/';
+
+ __gconv_path_elem[n].len = strspace - __gconv_path_elem[n].name;
+ if (__gconv_path_elem[n].len > __gconv_max_path_elem_len)
+ __gconv_max_path_elem_len = __gconv_path_elem[n].len;
+
+ *strspace++ = '\0';
+ ++n;
+ }
+ while ((elem = __strtok_r (NULL, ":", &gconv_path)) != NULL);
+
+ __gconv_path_elem[n].name = NULL;
+ __gconv_path_elem[n].len = 0;
}
- __libc_lock_unlock (lock);
+ if (__gconv_path_elem == NULL)
+ __gconv_path_elem = (struct path_elem *) &empty_path_elem;
+
+ free (cwd);
}
/* Read all configuration files found in the user-specified and the default
- path. */
-void
-attribute_hidden
+ path. This function is called only once during the program's lifetime so
+ we may disregard locking and synchronization. */
+static void
__gconv_read_conf (void)
{
void *modules = NULL;
@@ -602,6 +594,21 @@ __gconv_read_conf (void)
}
+/* This "once" variable is used to do a one-time load of the configuration. */
+__libc_once_define (static, once);
+
+
+/* Read all configuration files found in the user-specified and the default
+ path, but do it only "once" using __gconv_read_conf to do the actual
+ work. This is the function that must be called when reading iconv
+ configuration. */
+void
+attribute_hidden
+__gconv_load_conf (void)
+{
+ __libc_once (once, __gconv_read_conf);
+}
+
/* Free all resources if necessary. */
libc_freeres_fn (free_mem)
@@ -687,10 +687,6 @@ find_derivation (const char *toset, const char *toset_expand,
}
-/* Control of initialization. */
-__libc_once_define (static, once);
-
-
static const char *
do_lookup_alias (const char *name)
{
@@ -709,7 +705,7 @@ __gconv_compare_alias (const char *name1, const char *name2)
int result;
/* Ensure that the configuration data is read. */
- __libc_once (once, __gconv_read_conf);
+ __gconv_load_conf ();
if (__gconv_compare_alias_cache (name1, name2, &result) != 0)
result = strcmp (do_lookup_alias (name1) ?: name1,
@@ -729,7 +725,7 @@ __gconv_find_transform (const char *toset, const char *fromset,
int result;
/* Ensure that the configuration data is read. */
- __libc_once (once, __gconv_read_conf);
+ __gconv_load_conf ();
/* Acquire the lock. */
__libc_lock_lock (__gconv_lock);
@@ -196,8 +196,8 @@ extern int __gconv_compare_alias_cache (const char *name1, const char *name2,
extern void __gconv_release_step (struct __gconv_step *step)
attribute_hidden;
-/* Read all the configuration data and cache it. */
-extern void __gconv_read_conf (void) attribute_hidden;
+/* Read all the configuration data and cache it if not done so already. */
+extern void __gconv_load_conf (void) attribute_hidden;
/* Try to read module cache file. */
extern int __gconv_load_cache (void) attribute_hidden;
new file mode 100644
@@ -0,0 +1,146 @@
+/* Test that iconv works in a multi-threaded program.
+ Copyright (C) 2017 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
+ <http://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>
+
+#define TCOUNT 16
+#define CONV_INPUT "Hello, iconv!"
+
+
+#define WORKER_FAIL(fmt) \
+ do { printf ("FAIL: thread %lx: " fmt ": %m\n", tidx); \
+ pthread_exit ((void *) (long int) 1); } while (0)
+
+
+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");
+ if (cd == (iconv_t) -1)
+ WORKER_FAIL ("iconv_open");
+
+ xpthread_barrier_wait (&sync);
+
+ if (iconv (cd, &inbufpos, &inbytesleft, &outbufpos, &outbytesleft)
+ == (size_t) -1)
+ WORKER_FAIL ("iconv");
+ else
+ *outbufpos = '\0';
+
+ xpthread_barrier_wait (&sync);
+
+ if (iconv_close (cd))
+ WORKER_FAIL ("iconv_close");
+
+ /* 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 retval = 0;
+ 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]);
+ if (worker_output != NULL)
+ retval = 1;
+ }
+
+ xpthread_barrier_destroy (&sync);
+ xpthread_barrier_destroy (&sync_half_pool);
+
+ return retval;
+}
+
+#include <support/test-driver.c>