From b9db7df628a6a81a436e0afb1a699cb73aa4cf5b Mon Sep 17 00:00:00 2001
From: Christopher Friedt <cfriedt@meta.com>
Date: Fri, 25 Aug 2023 07:30:54 -0400
Subject: [PATCH] libc: common: support for C11 thread-specific storage

Add C11 thread-specific storage (tss) support to go with C11 threads
and mutexes.

Signed-off-by: Christopher Friedt <cfriedt@meta.com>
---
 lib/libc/common/CMakeLists.txt             |  1 +
 lib/libc/common/include/machine/_threads.h |  1 +
 lib/libc/common/include/threads.h          | 11 +++++
 lib/libc/common/source/thrd/tss.c          | 47 ++++++++++++++++++++++
 4 files changed, 60 insertions(+)
 create mode 100644 lib/libc/common/source/thrd/tss.c

diff --git a/lib/libc/common/CMakeLists.txt b/lib/libc/common/CMakeLists.txt
index a52d8dc8d4..a99ec825a0 100644
--- a/lib/libc/common/CMakeLists.txt
+++ b/lib/libc/common/CMakeLists.txt
@@ -12,6 +12,7 @@ zephyr_library_sources_ifdef(CONFIG_COMMON_LIBC_THRD
     source/thrd/cnd.c
     source/thrd/mtx.c
     source/thrd/thrd.c
+    source/thrd/tss.c
     )
 
 # Prevent compiler from optimizing calloc into an infinite recursive call
diff --git a/lib/libc/common/include/machine/_threads.h b/lib/libc/common/include/machine/_threads.h
index 0b82b87650..2742384599 100644
--- a/lib/libc/common/include/machine/_threads.h
+++ b/lib/libc/common/include/machine/_threads.h
@@ -14,6 +14,7 @@ extern "C" {
 typedef int cnd_t;
 typedef int mtx_t;
 typedef int thrd_t;
+typedef int tss_t;
 
 #ifdef __cplusplus
 }
diff --git a/lib/libc/common/include/threads.h b/lib/libc/common/include/threads.h
index f4a52f74b1..c7d2314444 100644
--- a/lib/libc/common/include/threads.h
+++ b/lib/libc/common/include/threads.h
@@ -63,6 +63,17 @@ int cnd_signal(cnd_t *cond);
 int cnd_broadcast(cnd_t *cond);
 void cnd_destroy(cnd_t *cond);
 
+#ifndef thread_local
+#define	thread_local _Thread_local
+#endif
+
+typedef void (*tss_dtor_t)(void *val);
+
+int tss_create(tss_t *key, tss_dtor_t destructor);
+void *tss_get(tss_t key);
+int tss_set(tss_t key, void *val);
+void tss_delete(tss_t key);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/libc/common/source/thrd/tss.c b/lib/libc/common/source/thrd/tss.c
new file mode 100644
index 0000000000..4b110d1717
--- /dev/null
+++ b/lib/libc/common/source/thrd/tss.c
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2023, Meta
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <errno.h>
+#include <threads.h>
+
+#include <zephyr/kernel.h>
+#include <zephyr/posix/pthread.h>
+
+int tss_create(tss_t *key, tss_dtor_t destructor)
+{
+	switch (pthread_key_create(key, destructor)) {
+	case 0:
+		return thrd_success;
+	case EAGAIN:
+		return thrd_busy;
+	case ENOMEM:
+		return thrd_nomem;
+	default:
+		return thrd_error;
+	}
+}
+
+void *tss_get(tss_t key)
+{
+	return pthread_getspecific(key);
+}
+
+int tss_set(tss_t key, void *val)
+{
+	switch (pthread_setspecific(key, val)) {
+	case 0:
+		return thrd_success;
+	case ENOMEM:
+		return thrd_nomem;
+	default:
+		return thrd_error;
+	}
+}
+
+void tss_delete(tss_t key)
+{
+	(void)pthread_key_delete(key);
+}