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-rw-r--r--include/Makefile.am1
-rw-r--r--include/osmocom/core/use_count.h228
-rw-r--r--src/Makefile.am1
-rw-r--r--src/use_count.c279
-rw-r--r--tests/Makefile.am5
-rw-r--r--tests/testsuite.at7
-rw-r--r--tests/use_count/use_count_test.c339
-rw-r--r--tests/use_count/use_count_test.err171
-rw-r--r--tests/use_count/use_count_test.ok0
9 files changed, 1031 insertions, 0 deletions
diff --git a/include/Makefile.am b/include/Makefile.am
index 6ed7fe67..7b9e3479 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -53,6 +53,7 @@ nobase_include_HEADERS = \
osmocom/core/utils.h \
osmocom/core/write_queue.h \
osmocom/core/sockaddr_str.h \
+ osmocom/core/use_count.h \
osmocom/crypt/auth.h \
osmocom/crypt/gprs_cipher.h \
osmocom/ctrl/control_cmd.h \
diff --git a/include/osmocom/core/use_count.h b/include/osmocom/core/use_count.h
new file mode 100644
index 00000000..6a4bf1f3
--- /dev/null
+++ b/include/osmocom/core/use_count.h
@@ -0,0 +1,228 @@
+/*! \file use_count.h
+ * Generic object usage counter API (get, put and deallocate on zero count).
+ */
+/*
+ * (C) 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * Author: Neels Hofmeyr <neels@hofmeyr.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#pragma once
+
+#include <stdint.h>
+#include <stdlib.h>
+
+#include <osmocom/core/linuxlist.h>
+
+/*! \defgroup use_count Use Counter
+ * @{
+ * \file use_count.h
+ */
+
+struct osmo_use_count_entry;
+
+/*! Invoked when a use count changes.
+ *
+ * The implementation is free to trigger actions on arbitrary use count changes, typically to free the
+ * use_count->talloc_object when the total use count reaches zero.
+ *
+ * The implementation may modify use_count_entry->count, for example for handling of get()/put() bugs, to clamp specific use
+ * tokens to specific counts, or to prevent the caller from put()ting into negative counts. When returning an error,
+ * there is no implicit undo -- if errors need to be corrected, this function is responsible for that.
+ *
+ * Be aware: use token strings are not copied, and use count entries usually remain listed also when they reach a zero
+ * count. This is trivially perfectly ok when using string literals as use tokens. It is also possible to use
+ * dynamically allocated string tokens, but should a use token string become invalid memory when reaching zero count, it
+ * is the responsibility of this function to set the use_count_entry->use = NULL; this is required to avoid subsequent
+ * osmo_use_count_get_put() invocations from calling strcmp() on invalid memory. (Setting use = NULL cannot be done
+ * implicitly after this callback invocation, because callback implementations are allowed to completely deallocate the
+ * talloc_object and the use_count list entries, and setting use = NULL after that would be a use-after-free.)
+ *
+ * \param[in] use_count_entry Use count entry that is being modified.
+ * \param[in] old_use_count Use count the item had before the change in use count.
+ * \param[in] file Source file string, passed in as __FILE__ from macro osmo_use_count_get_put().
+ * \param[in] line Source file line, passed in as __LINE__ from macro osmo_use_count_get_put().
+ * \return 0 on success, negative if any undesired use count is reached; this rc will be returned by
+ * osmo_use_count_get_put().
+ */
+typedef int (* osmo_use_count_cb_t )(struct osmo_use_count_entry *use_count_entry, int32_t old_use_count,
+ const char *file, int line);
+
+/*! Use counter state for one used object, managing N distinct named counters.
+ *
+ * Manage any number of uses of an object, with name tokens given to each use.
+ *
+ * A typical use tracking done by a single instance of this struct may look like:
+ * "VLR subscr MSISDN-23 + SMS-receiver: now used by 6 (attached,2*SMS-receiver,SMS-pending,SMS,Paging)"
+ * (This is a DREF log statement from an osmo-msc run delivering an SMS.)
+ *
+ * Use tokens are given as const char* strings. Typically string literals like "foo", __func__, or also NULL. Tokens may
+ * be dynamically allocated or static char[] buffers as long as they are guaranteed to remain unchanged while referenced
+ * by an osmo_use_count_entry. (Breakage occurs if one token magically changes to equal another listed token.)
+ *
+ * Instead of using string literals in the code directly, callers should use a #define, so that typos are caught at
+ * compile time rather than introducing obscure failures that are hard to spot for humans -- don't use foo_get("bar")
+ * and foo_put("bar"), but '#define FOO_USE_BAR "bar"' for foo_get(FOO_USE_BAR) and foo_put(FOO_USE_BAR).
+ *
+ * Counts are int32_t values, a separate count per use token string. Counts can be negative, though in the typical use
+ * case are only positive or 0. Enforcing a range is entirely up to the osmo_use_count_cb_t() implementation.
+ *
+ * The talloc_object must be a pointer eligible to be a talloc context, i.e. either obtained from a function like
+ * talloc_zero() or NULL. talloc_object is typically a pointer to the object that this struct is a member of. Use count
+ * entries may be allocated as talloc children of this (see also "Avoiding dynamic allocation" below).
+ *
+ * The use_cb() implementation allows to trigger actions when reaching specific use counts, e.g. deallocate when
+ * reaching a total sum across all use tokens of zero.
+ *
+ * On initialization, this struct can be left fully zero initialized (the llist_head use_counts is implicitly
+ * initialized upon the first osmo_use_count_get_put()). Usually, set only a talloc_object and a use_cb, though neither
+ * is strictly required.
+ *
+ * Avoiding dynamic allocation: dynamic allocation can be avoided completely by providing sufficient static use count
+ * entries with osmo_use_count_make_static_entries(). Otherwise, each new use token will dynamically allocate a new
+ * osmo_use_count_entry; note that once allocated, these entries stay around even if they reached an entry count of
+ * zero, and will be re-used for subsequent use count tokens. So even if not using osmo_use_count_make_static_entries(),
+ * each osmo_use_count will keep dynamic allocations at a minimum. See also the documentation for osmo_use_count_cb_t.
+ *
+ * List traversal considerations: your typical use count list would max at about six entries in practice. Traversing six
+ * llist->next pointers is less effort than doing a common strlen().
+ *
+ * Obtaining the total use count: osmo_use_count_total() traverses all use token entries and forms a sum. It is trivial
+ * to keep a separate total count that completely avoids the need for calling this function, which is entirely up to the
+ * individual osmo_use_count_cb_t() implementation. The optimization gained is usually not worth it, though.
+ *
+ * Use token comparison considerations: strcmp() to compare use tokens is a fairly good tradeoff:
+ * - when the strings differ, strcmp() usually exits on the first or second character.
+ * - when the strings are identical, they are usually the exact same char* address (from compile-time string constant),
+ * meaning that strcmp() is completely skipped.
+ * (quote: "if (e->use == use || (use && e->use && !strcmp(e->use, use)))")
+ * - if we specified compile-time string constant use as requirement, we wouldn't need strcmp() at all, but this
+ * minuscule overhead has the benefit of complete correctness for any kinds of use token strings.
+ *
+ * Example:
+ *
+ * struct foo {
+ * struct osmo_use_count use_count;
+ * };
+ *
+ * // Convenience macros for struct foo instances. These are strict about use count errors.
+ * #define foo_get(FOO, USE) OSMO_ASSERT( osmo_use_count_get_put(&(FOO)->use_count, USE, 1) == 0 );
+ * #define foo_put(FOO, USE) OSMO_ASSERT( osmo_use_count_get_put(&(FOO)->use_count, USE, -1) == 0 );
+ *
+ * int foo_use_cb(struct osmo_use_count_entry *use_count_entry, int32_t old_use_count, const char *file, int line)
+ * {
+ * struct foo *foo = use_count_entry->use_count->talloc_object;
+ * if (osmo_use_count_total(&use_count_entry->use_count) == 0)
+ * talloc_free(foo);
+ * }
+ *
+ * // The function name is a convenient use token:
+ * void rx_stop_baz_request(struct foo *foo)
+ * {
+ * foo_get(foo, __func__);
+ *
+ * foo_put(foo, "baz");
+ * printf("Stopped Bazing (%p)\n", foo);
+ *
+ * foo_put(foo, __func__);
+ * }
+ *
+ * void use_count_example()
+ * {
+ * struct foo *foo = talloc_zero(ctx, struct foo);
+ * *foo = (struct foo){
+ * .use_count = {
+ * .talloc_object = foo,
+ * .use_cb = foo_use_cb,
+ * },
+ * };
+ *
+ * foo_get(foo, "bar"); // one osmo_use_count_entry was allocated
+ * foo_get(foo, "baz"); // a second osmo_use_count_entry was allocated
+ * foo_get(foo, "baz"); // still two entries
+ *
+ * printf("use: %s\n", osmo_use_count_name_buf(namebuf, sizeof(namebuf), &foo->use_count));
+ * // "use: 3 (bar,2*baz)"
+ *
+ * foo_put(foo, "bar"); // still two entries, one entry is idle ("bar"=0)
+ * foo_put(foo, "baz");
+ * rx_stop_baz_request(foo);
+ * // Final "baz" was put(), foo_use_cb() deallocated object foo, as well as all use count entries.
+ * };
+ */
+struct osmo_use_count {
+ /*! Context to talloc-allocate use count entries from (if at all necessary); back-pointer to the owning object
+ * for osmo_use_count_cb_t implementations. */
+ void *talloc_object;
+ /*! If not NULL, this is invoked for each use count change. */
+ osmo_use_count_cb_t use_cb;
+ /*! List of use tokens. No need to touch this, the llist is initialized implicitly. */
+ struct llist_head use_counts;
+};
+
+/*! One named counter in the list managed by osmo_use_count.
+ * Gets created as necessary by osmo_use_count_get_put(). The total current use count of an object is the sum of all
+ * individual osmo_use_count_entry->count.
+ *
+ * object <--backpointer-+
+ * t| .osmo_use_count |
+ * a| .talloc_object ------------+
+ * l| .use_counts llist: use count
+ * l|-> - osmo_use_count_entry: "foo" 1
+ * o|-> - osmo_use_count_entry: "bar" 3
+ * c|-> - osmo_use_count_entry: "baz" 0 (currently unused entry)
+ */
+struct osmo_use_count_entry {
+ /*! Entry in osmo_use_count->use_counts. */
+ struct llist_head entry;
+ /*! Parent use count and backpointer to the talloc_object. */
+ struct osmo_use_count *use_count;
+ /*! Use token string that was passed to osmo_use_count_get_put(). */
+ const char *use;
+ /*! Current use count amount for only this use token string.
+ * If zero, this entry is currently unused and kept around to avoid frequent de-/allocation. */
+ int32_t count;
+};
+
+/*! Change the use count for a given use token.
+ * \param USE_LIST A struct osmo_use_count*, e.g. &my_obj->use_count.
+ * \param USE A use token: arbitrary string (const char*). This must remain valid memory, e.g. string constants.
+ * \param CHANGE Signed integer value to add to the use count: positive means get(), negative means put().
+ * \return Negative on range violations or USE_LIST == NULL, the use_cb()'s return value, or 0 on success.
+ */
+#define osmo_use_count_get_put(USE_LIST, USE, CHANGE) \
+ _osmo_use_count_get_put(USE_LIST, USE, CHANGE, __FILE__, __LINE__)
+
+int _osmo_use_count_get_put(struct osmo_use_count *uc, const char *use, int32_t change,
+ const char *file, int line);
+
+const char *osmo_use_count_name_buf(char *buf, size_t buf_len, const struct osmo_use_count *uc);
+
+int32_t osmo_use_count_total(const struct osmo_use_count *uc);
+int32_t osmo_use_count_by(const struct osmo_use_count *uc, const char *use);
+
+struct osmo_use_count_entry *osmo_use_count_find(const struct osmo_use_count *uc, const char *use);
+void osmo_use_count_free(struct osmo_use_count_entry *use_count_entry);
+
+void osmo_use_count_make_static_entries(struct osmo_use_count *uc, struct osmo_use_count_entry *buf,
+ size_t buf_n_entries);
+
+/*! @} */
diff --git a/src/Makefile.am b/src/Makefile.am
index 1fae8b0a..aaf2233e 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -26,6 +26,7 @@ libosmocore_la_SOURCES = timer.c timer_gettimeofday.c timer_clockgettime.c \
isdnhdlc.c \
tdef.c \
sockaddr_str.c \
+ use_count.c \
$(NULL)
if HAVE_SSSE3
diff --git a/src/use_count.c b/src/use_count.c
new file mode 100644
index 00000000..453d2ae8
--- /dev/null
+++ b/src/use_count.c
@@ -0,0 +1,279 @@
+/*! \file use_count.c
+ * Generic object usage counter Implementation (get, put and deallocate on zero count).
+ */
+/*
+ * (C) 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * Author: Neels Hofmeyr <neels@hofmeyr.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <errno.h>
+#include <inttypes.h>
+#include <string.h>
+
+#include <osmocom/core/linuxlist.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/use_count.h>
+
+/*! \addtogroup use_count
+ *
+ * Generic object usage counter (get, put and deallocate on zero count).
+ *
+ * For an example and a detailed description, see struct osmo_use_count.
+ *
+ * @{
+ * \file use_count.c
+ */
+
+/*! Add two int32_t but make sure to min- and max-clamp at INT32_MIN and INT32_MAX, respectively. */
+static inline bool count_safe(int32_t *val_p, int32_t add)
+{
+ int32_t val = *val_p;
+
+ /* A simpler implementation would just let the integer overflow and compare with previous value afterwards, but
+ * that causes runtime errors in the address sanitizer. So let's just do this without tricks. */
+ if (add < 0 && val < 0 && val - INT32_MIN < -add) {
+ *val_p = INT32_MIN;
+ return false;
+ }
+
+ if (add > 0 && val > 0 && INT32_MAX - val < add) {
+ *val_p = INT32_MAX;
+ return false;
+ }
+
+ *val_p = val + add;
+ return true;
+}
+
+/*! Return the sum of all use counts, min- and max-clamped at INT32_MIN and INT32_MAX.
+ * \param[in] uc Use counts to sum up.
+ * \return Accumulated counts, or 0 if uc is NULL.
+ */
+int32_t osmo_use_count_total(const struct osmo_use_count *uc)
+{
+ struct osmo_use_count_entry *e;
+ int32_t total = 0;
+
+ if (!uc || !uc->use_counts.next)
+ return 0;
+
+ llist_for_each_entry(e, &uc->use_counts, entry) {
+ count_safe(&total, e->count);
+ }
+ return total;
+}
+
+/*! Return use count by a single use token.
+ * \param[in] uc Use counts to look up in.
+ * \param[in] use Use token.
+ * \return Use count, or 0 if uc is NULL or use token is not present.
+ */
+int32_t osmo_use_count_by(const struct osmo_use_count *uc, const char *use)
+{
+ const struct osmo_use_count_entry *e;
+ if (!uc)
+ return 0;
+ e = osmo_use_count_find(uc, use);
+ if (!e)
+ return 0;
+ return e->count;
+}
+
+/*! Write a comprehensive listing of use counts to a string buffer.
+ * Reads like "12 (3*barring,fighting,8*kungfoo)".
+ * \param[inout] buf Destination buffer.
+ * \param[in] buf_len sizeof(buf).
+ * \param[in] uc Use counts to print.
+ * \return buf, always nul-terminated (except when buf_len < 1).
+ */
+const char *osmo_use_count_name_buf(char *buf, size_t buf_len, const struct osmo_use_count *uc)
+{
+ int32_t count = osmo_use_count_total(uc);
+ struct osmo_strbuf sb = { .buf = buf, .len = buf_len };
+ struct osmo_use_count_entry *e;
+ bool first;
+
+ OSMO_STRBUF_PRINTF(sb, "%" PRId32 " (", count);
+
+ first = true;
+ llist_for_each_entry(e, &uc->use_counts, entry) {
+ if (!e->count)
+ continue;
+ if (!first)
+ OSMO_STRBUF_PRINTF(sb, ",");
+ first = false;
+ if (e->count != 1)
+ OSMO_STRBUF_PRINTF(sb, "%" PRId32 "*", e->count);
+ OSMO_STRBUF_PRINTF(sb, "%s", e->use ? : "NULL");
+ }
+ if (first)
+ OSMO_STRBUF_PRINTF(sb, "-");
+ OSMO_STRBUF_PRINTF(sb, ")");
+ return buf;
+}
+
+/* Return a use token's use count entry -- probably you want osmo_use_count_by() instead.
+ * \param[in] uc Use counts to look up in.
+ * \param[in] use Use token.
+ * \return matching entry, or NULL if not present.
+ */
+struct osmo_use_count_entry *osmo_use_count_find(const struct osmo_use_count *uc, const char *use)
+{
+ struct osmo_use_count_entry *e;
+ if (!uc->use_counts.next)
+ return NULL;
+ llist_for_each_entry(e, &uc->use_counts, entry) {
+ if (e->use == use || (use && e->use && !strcmp(e->use, use)))
+ return e;
+ }
+ return NULL;
+}
+
+/*! Find a use count entry that currently has zero count, and re-use that for this new use token. */
+static struct osmo_use_count_entry *osmo_use_count_repurpose_zero_entry(struct osmo_use_count *uc, const char *use)
+{
+ struct osmo_use_count_entry *e;
+ if (!uc->use_counts.next)
+ return NULL;
+ llist_for_each_entry(e, &uc->use_counts, entry) {
+ if (!e->count) {
+ e->use = use;
+ return e;
+ }
+ }
+ return NULL;
+}
+
+/*! Allocate a new use count entry, happens implicitly in osmo_use_count_get_put(). */
+static struct osmo_use_count_entry *osmo_use_count_create(struct osmo_use_count *uc, const char *use)
+{
+ struct osmo_use_count_entry *e = talloc_zero(uc->talloc_object, struct osmo_use_count_entry);
+ if (!e)
+ return NULL;
+ *e = (struct osmo_use_count_entry){
+ .use_count = uc,
+ .use = use,
+ };
+ if (!uc->use_counts.next)
+ INIT_LLIST_HEAD(&uc->use_counts);
+ llist_add_tail(&e->entry, &uc->use_counts);
+ return e;
+}
+
+/*! Deallocate a use count entry.
+ * Normally, this is not necessary -- it is ok and even desirable to leave use count entries around even when they reach
+ * a count of zero, until the use_count->talloc_object deallocates and removes all of them in one flush. This avoids
+ * repeated allocation and deallocation for use tokens, because use count entries that have reached zero count are
+ * repurposed for any other use tokens. A cleanup makes sense only if a very large number of differing use tokens surged
+ * at the same time, and the owning object will not be deallocated soon; if so, this should be done by the
+ * osmo_use_count_cb_t implementation.
+ *
+ * osmo_use_count_free() must *not* be called on use count entries that were added by
+ * osmo_use_count_make_static_entries(). This is the responsibility of the osmo_use_count_cb_t() implementation.
+ *
+ * \param[in] use_count_entry Use count entry to unlist and free.
+ */
+void osmo_use_count_free(struct osmo_use_count_entry *use_count_entry)
+{
+ if (!use_count_entry)
+ return;
+ llist_del(&use_count_entry->entry);
+ talloc_free(use_count_entry);
+}
+
+/*! Implementation for osmo_use_count_get_put(), which can also be directly invoked to pass source file information. For
+ * arguments besides file and line, see osmo_use_count_get_put().
+ * \param[in] file Source file path, as in __FILE__.
+ * \param[in] line Source file line, as in __LINE__.
+ */
+int _osmo_use_count_get_put(struct osmo_use_count *uc, const char *use, int32_t change,
+ const char *file, int line)
+{
+ struct osmo_use_count_entry *e;
+ int32_t old_use_count;
+ if (!change)
+ return 0;
+
+ e = osmo_use_count_find(uc, use);
+ if (!e)
+ e = osmo_use_count_repurpose_zero_entry(uc, use);
+ if (!e)
+ e = osmo_use_count_create(uc, use);
+ if (!e)
+ return -ENOMEM;
+
+ if (!e->count) {
+ /* move to end */
+ llist_del(&e->entry);
+ llist_add_tail(&e->entry, &uc->use_counts);
+ }
+
+ old_use_count = e->count;
+ if (!count_safe(&e->count, change)) {
+ e->count = old_use_count;
+ return -ERANGE;
+ }
+
+ if (uc->use_cb)
+ return uc->use_cb(e, old_use_count, file, line);
+ return 0;
+}
+
+/*! Add N static use token entries to avoid dynamic allocation of use count tokens.
+ * When not using this function, use count entries are talloc allocated from uc->talloc_object as talloc context. This
+ * means that there are small dynamic allocations for each use count token. osmo_use_count_get_put() normally leaves
+ * zero-count entries around and re-purposes them later, so the number of small allocations is at most the number of
+ * concurrent differently-named uses of the same object. If that is not enough, this function allows completely avoiding
+ * dynamic use count allocations, by adding N static entries with a zero count and a NULL use token. They will be used
+ * by osmo_use_count_get_put(), and, if the caller avoids using osmo_use_count_free(), the osmo_use_count implementation
+ * never deallocates them. The idea is that the entries are members of the uc->talloc_object, or that they will by other
+ * means be implicitly deallocated by the talloc_object. It is fine to call
+ * osmo_use_count_make_static_entries(buf_n_entries=N) and later have more than N concurrent uses, i.e. it is no problem
+ * to mix static and dynamic entries. To completely avoid dynamic use count entries, N has to >= the maximum number of
+ * concurrent differently-named uses that will occur in the lifetime of the talloc_object.
+ *
+ * struct my_object {
+ * struct osmo_use_count use_count;
+ * struct osmo_use_count_entry use_count_buf[3]; // planning for 3 concurrent users
+ * };
+ *
+ * void example() {
+ * struct my_object *o = talloc_zero(ctx, struct my_object);
+ * osmo_use_count_make_static_entries(&o->use_count, o->use_count_buf, ARRAY_SIZE(o->use_count_buf));
+ * }
+ */
+void osmo_use_count_make_static_entries(struct osmo_use_count *uc, struct osmo_use_count_entry *buf,
+ size_t buf_n_entries)
+{
+ size_t idx;
+ if (!uc->use_counts.next)
+ INIT_LLIST_HEAD(&uc->use_counts);
+ for (idx = 0; idx < buf_n_entries; idx++) {
+ struct osmo_use_count_entry *e = &buf[idx];
+ *e = (struct osmo_use_count_entry){
+ .use_count = uc,
+ };
+ llist_add_tail(&e->entry, &uc->use_counts);
+ }
+}
+
+/*! @} */
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 88bcd7e9..d123ee2a 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -31,6 +31,7 @@ check_PROGRAMS = timer/timer_test sms/sms_test ussd/ussd_test \
tdef/tdef_vty_test_config_subnode \
tdef/tdef_vty_test_dynamic \
sockaddr_str/sockaddr_str_test \
+ use_count/use_count_test \
$(NULL)
if ENABLE_MSGFILE
@@ -240,6 +241,9 @@ tdef_tdef_vty_test_dynamic_LDADD = $(LDADD) $(top_builddir)/src/vty/libosmovty.l
sockaddr_str_sockaddr_str_test_SOURCES = sockaddr_str/sockaddr_str_test.c
sockaddr_str_sockaddr_str_test_LDADD = $(LDADD)
+use_count_use_count_test_SOURCES = use_count/use_count_test.c
+use_count_use_count_test_LDADD = $(LDADD)
+
# The `:;' works around a Bash 3.2 bug when the output is not writeable.
$(srcdir)/package.m4: $(top_srcdir)/configure.ac
:;{ \
@@ -309,6 +313,7 @@ EXTRA_DIST = testsuite.at $(srcdir)/package.m4 $(TESTSUITE) \
tdef/tdef_vty_test_config_subnode.vty \
tdef/tdef_vty_test_dynamic.vty \
sockaddr_str/sockaddr_str_test.ok \
+ use_count/use_count_test.ok use_count/use_count_test.err \
$(NULL)
DISTCLEANFILES = atconfig atlocal conv/gsm0503_test_vectors.c
diff --git a/tests/testsuite.at b/tests/testsuite.at
index db2003f4..5a6e8020 100644
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -337,3 +337,10 @@ AT_KEYWORDS([sockaddr_str])
cat $abs_srcdir/sockaddr_str/sockaddr_str_test.ok > expout
AT_CHECK([$abs_top_builddir/tests/sockaddr_str/sockaddr_str_test], [0], [expout], [ignore])
AT_CLEANUP
+
+AT_SETUP([use_count])
+AT_KEYWORDS([use_count])
+cat $abs_srcdir/use_count/use_count_test.ok > expout
+cat $abs_srcdir/use_count/use_count_test.err > experr
+AT_CHECK([$abs_top_builddir/tests/use_count/use_count_test], [0], [expout], [experr])
+AT_CLEANUP
diff --git a/tests/use_count/use_count_test.c b/tests/use_count/use_count_test.c
new file mode 100644
index 00000000..0b081c9c
--- /dev/null
+++ b/tests/use_count/use_count_test.c
@@ -0,0 +1,339 @@
+/* Test implementation for osmo_use_count API. */
+/*
+ * (C) 2019 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
+ *
+ * All Rights Reserved
+ *
+ * Author: Neels Hofmeyr <neels@hofmeyr.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <limits.h>
+
+#include <osmocom/core/logging.h>
+#include <osmocom/core/application.h>
+#include <osmocom/core/fsm.h>
+
+#include <osmocom/core/use_count.h>
+
+static void *ctx = NULL;
+
+#define log(fmt, args...) fprintf(stderr, fmt, ##args)
+
+enum {
+ DFOO,
+};
+
+#define FOO_USE_BARRING "barring"
+#define FOO_USE_FIGHTING "fighting"
+#define FOO_USE_KUNG "kungfoo"
+#define FOO_USE_RELEASING "releasing"
+
+LLIST_HEAD(all_foo);
+
+struct foo {
+ struct llist_head entry;
+ struct osmo_fsm_inst *fi;
+ struct osmo_use_count use_count;
+ struct osmo_use_count_entry use_count_buf[10];
+};
+
+enum foo_fsm_events {
+ FOO_EV_UNUSED,
+};
+
+static char name_buf[1024];
+#define use_count_name(UL) osmo_use_count_name_buf(name_buf, sizeof(name_buf), UL)
+
+int foo_use_cb(struct osmo_use_count_entry *use_count_entry, int32_t old_use_count,
+ const char *file, int line)
+{
+ struct osmo_use_count *use_count = use_count_entry->use_count;
+ struct foo *foo = use_count->talloc_object;
+ const char *use = use_count_entry->use;
+ int32_t new_use_count = use_count_entry->count;
+
+ if (use && (!strcmp(use, FOO_USE_BARRING) || !strcmp(use, FOO_USE_RELEASING))
+ && new_use_count > 1) {
+ LOGPFSMLSRC(foo->fi, LOGL_ERROR, file, line,
+ "Attempt to get more than one %s\n", use);
+ /* Fix the use count */
+ use_count_entry->count = 1;
+ return -ERANGE;
+ }
+
+ LOGPFSMLSRC(foo->fi, LOGL_NOTICE, file, line, "%s %+d %s: now used by %s\n",
+ foo->fi->id, new_use_count - old_use_count, use ? : "NULL", use_count_name(use_count));
+
+ if (new_use_count < 0) {
+ LOGPFSMLSRC(foo->fi, LOGL_ERROR, file, line, "Negative use count on %s: %s\n",
+ use ? : "NULL", use_count_name(use_count));
+ /* Let it pass for the sake of this test */
+ }
+
+ if (osmo_use_count_total(use_count) == 0)
+ osmo_fsm_inst_dispatch(foo->fi, FOO_EV_UNUSED, NULL);
+ return 0;
+}
+
+#define foo_get_put(FOO, USE, CHANGE) do { \
+ int rc = osmo_use_count_get_put(&(FOO)->use_count, USE, CHANGE); \
+ if (rc) \
+ log("osmo_use_count_get_put(%s, %s, %d) returned error: %d %s\n", \
+ (FOO)->fi->id, USE ? : "NULL", CHANGE, rc, strerror(-rc)); \
+ } while(0)
+
+#define foo_get(FOO, USE) foo_get_put(FOO, USE, 1)
+#define foo_put(FOO, USE) foo_get_put(FOO, USE, -1)
+
+enum foo_fsm_states {
+ FOO_ST_IN_USE,
+ FOO_ST_IN_RELEASE,
+};
+
+void foo_fsm_in_use(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+ OSMO_ASSERT(event == FOO_EV_UNUSED);
+ osmo_fsm_inst_state_chg(fi, FOO_ST_IN_RELEASE, 0, 0);
+}
+
+void foo_fsm_in_release_onenter(struct osmo_fsm_inst *fi, uint32_t prev_state)
+{
+ struct foo *foo = fi->priv;
+ foo_get(foo, FOO_USE_RELEASING);
+}
+
+void foo_fsm_in_release(struct osmo_fsm_inst *fi, uint32_t event, void *data)
+{
+ OSMO_ASSERT(event == FOO_EV_UNUSED);
+ osmo_fsm_inst_term(fi, OSMO_FSM_TERM_REGULAR, NULL);
+}
+
+
+#define S(x) (1 << (x))
+
+static const struct osmo_fsm_state foo_fsm_states[] = {
+ [FOO_ST_IN_USE] = {
+ .name = "IN_USE",
+ .in_event_mask = 0
+ | S(FOO_EV_UNUSED)
+ ,
+ .out_state_mask = 0
+ | S(FOO_ST_IN_RELEASE)
+ ,
+ .action = foo_fsm_in_use,
+ },
+ [FOO_ST_IN_RELEASE] = {
+ .name = "IN_RELEASE",
+ .in_event_mask = 0
+ | S(FOO_EV_UNUSED)
+ ,
+ .out_state_mask = 0
+ ,
+ .onenter = foo_fsm_in_release_onenter,
+ .action = foo_fsm_in_release,
+ },
+};
+
+static const struct value_string foo_fsm_event_names[] = {
+ OSMO_VALUE_STRING(FOO_EV_UNUSED),
+ {}
+};
+
+void foo_cleanup(struct osmo_fsm_inst *fi, enum osmo_fsm_term_cause cause)
+{
+ struct foo *foo = fi->priv;
+ llist_del(&foo->entry);
+}
+
+static struct osmo_fsm foo_fsm = {
+ .name = "foo",
+ .states = foo_fsm_states,
+ .event_names = foo_fsm_event_names,
+ .num_states = ARRAY_SIZE(foo_fsm_states),
+ .log_subsys = DFOO,
+ .cleanup = foo_cleanup,
+};
+
+static struct foo *foo_alloc(const char *name, size_t static_entries)
+{
+ struct foo *foo;
+ struct osmo_fsm_inst *fi = osmo_fsm_inst_alloc(&foo_fsm, ctx, NULL, LOGL_DEBUG, name);
+ OSMO_ASSERT(fi);
+ OSMO_ASSERT(static_entries <= ARRAY_SIZE(foo->use_count_buf));
+
+ foo = talloc_zero(fi, struct foo);
+ *foo = (struct foo){
+ .fi = fi,
+ .use_count = {
+ .talloc_object = foo,
+ .use_cb = foo_use_cb,
+ },
+ };
+ fi->priv = foo;
+
+ osmo_use_count_make_static_entries(&foo->use_count, foo->use_count_buf, static_entries);
+
+ llist_add_tail(&foo->entry, &all_foo);
+ return foo;
+}
+
+void print_foos()
+{
+ int count = 0;
+ struct foo *foo;
+ fprintf(stderr, "\nall use counts:\n");
+ llist_for_each_entry(foo, &all_foo, entry) {
+ fprintf(stderr, "%s: %s\n", foo->fi->id, use_count_name(&foo->use_count));
+ count++;
+ }
+ fprintf(stderr, "%d foos\n\n", count);
+}
+
+static void test_use_count_fsm()
+{
+ struct foo *a, *b, *c;
+ log("\n%s()\n", __func__);
+
+ a = foo_alloc("a", 0);
+ b = foo_alloc("b", 2);
+ c = foo_alloc("c", 10);
+ print_foos();
+
+ log("A few gets and puts, logging source file information\n");
+ log_set_print_filename2(osmo_stderr_target, LOG_FILENAME_BASENAME);
+ foo_get(a, FOO_USE_BARRING);
+
+ foo_get(b, FOO_USE_BARRING);
+ foo_get(b, FOO_USE_FIGHTING);
+
+ print_foos();
+
+ log("Attempt to get more than one on limited 'barring' user:\n");
+ foo_get(b, FOO_USE_BARRING);
+ print_foos();
+
+ log("Put away one user of b\n");
+ foo_put(b, FOO_USE_BARRING);
+ print_foos();
+
+ log("(no longer log source file information)\n");
+ log_set_print_filename2(osmo_stderr_target, LOG_FILENAME_NONE);
+
+ log("Test null use token\n");
+ foo_get(a, NULL);
+ print_foos();
+ foo_put(a, NULL);
+ print_foos();
+
+ log("Put away last user of a, goes to RELEASING state and waits for a hypothetic async release process\n");
+ foo_put(a, FOO_USE_BARRING);
+ print_foos();
+
+ log("Async releasing of a is done, will dealloc\n");
+ foo_put(a, FOO_USE_RELEASING);
+ print_foos();
+
+ log("Use b multiple times\n");
+ foo_get(b, FOO_USE_KUNG);
+ foo_get(b, FOO_USE_KUNG);
+
+ foo_put(b, FOO_USE_KUNG);
+ foo_get(b, FOO_USE_KUNG);
+
+ foo_get(b, FOO_USE_KUNG);
+ print_foos();
+
+ log("Test range: set kung-fu to INT32_MAX-1, then get three more; total count gets max-clamped to INT32_MAX\n");
+ foo_get_put(b, FOO_USE_KUNG, INT32_MAX-1 - osmo_use_count_by(&b->use_count, FOO_USE_KUNG));
+ print_foos();
+ foo_get(b, FOO_USE_KUNG);
+ foo_get(b, FOO_USE_KUNG);
+ foo_get(b, FOO_USE_KUNG);
+ foo_get_put(b, FOO_USE_FIGHTING, 2);
+ foo_get_put(b, FOO_USE_KUNG, -3);
+ foo_put(b, FOO_USE_KUNG);
+ foo_put(b, FOO_USE_KUNG);
+ foo_get(b, FOO_USE_FIGHTING);
+ foo_get(b, FOO_USE_FIGHTING);
+ foo_get(b, FOO_USE_FIGHTING);
+ print_foos();
+
+ log("Release all uses of b\n");
+ foo_get_put(b, FOO_USE_KUNG, - osmo_use_count_by(&b->use_count, FOO_USE_KUNG));
+ foo_get_put(b, FOO_USE_FIGHTING, - osmo_use_count_by(&b->use_count, FOO_USE_FIGHTING));
+
+ log("Signal async release as done\n");
+ foo_put(b, FOO_USE_RELEASING);
+ print_foos();
+
+ log("Release something not gotten before: a get/put bug goes into negative count\n");
+ foo_put(c, FOO_USE_KUNG);
+ print_foos();
+ log("More negative\n");
+ foo_put(c, FOO_USE_KUNG);
+ foo_put(c, FOO_USE_KUNG);
+ print_foos();
+
+ log("Also release c\n");
+ foo_get_put(c, FOO_USE_KUNG, 4);
+ foo_put(c, FOO_USE_KUNG);
+ log("Signal async release as done\n");
+ foo_put(c, FOO_USE_RELEASING);
+ print_foos();
+}
+
+static const struct log_info_cat default_categories[] = {
+ [DFOO] = {
+ .name = "DFOO",
+ .description = "FOO",
+ .enabled = 1, .loglevel = LOGL_DEBUG,
+ },
+};
+
+static const struct log_info log_info = {
+ .cat = default_categories,
+ .num_cat = ARRAY_SIZE(default_categories),
+};
+
+
+int main(int argc, char **argv)
+{
+ ctx = talloc_named_const(NULL, 0, "use_count_test.c");
+
+ osmo_fsm_log_addr(false);
+
+ osmo_init_logging2(ctx, &log_info);
+
+ log_set_print_filename2(osmo_stderr_target, LOG_FILENAME_BASENAME);
+ log_set_print_filename2(osmo_stderr_target, LOG_FILENAME_NONE);
+ log_set_print_filename_pos(osmo_stderr_target, LOG_FILENAME_POS_LINE_END);
+ log_set_print_category(osmo_stderr_target, 1);
+ log_set_print_category_hex(osmo_stderr_target, 0);
+ log_set_print_level(osmo_stderr_target, 1);
+ log_set_use_color(osmo_stderr_target, 0);
+
+ osmo_fsm_register(&foo_fsm);
+
+ test_use_count_fsm();
+
+ return EXIT_SUCCESS;
+}
diff --git a/tests/use_count/use_count_test.err b/tests/use_count/use_count_test.err
new file mode 100644
index 00000000..97e74a51
--- /dev/null
+++ b/tests/use_count/use_count_test.err
@@ -0,0 +1,171 @@
+
+test_use_count_fsm()
+DFOO DEBUG foo(a){IN_USE}: Allocated
+DFOO DEBUG foo(b){IN_USE}: Allocated
+DFOO DEBUG foo(c){IN_USE}: Allocated
+
+all use counts:
+a: 0 (-)
+b: 0 (-)
+c: 0 (-)
+3 foos
+
+A few gets and puts, logging source file information
+DFOO NOTICE foo(a){IN_USE}: a +1 barring: now used by 1 (barring) (use_count_test.c:22