Test the initjmp() function when HAVE_INITJMP is set. Use the test as an
example in the API documentation.
Signed-off-by: Jerome Forissier <jerome.foriss...@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
---
doc/api/setjmp.rst | 10 +++++++
test/lib/Makefile | 1 +
test/lib/initjmp.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 84 insertions(+)
create mode 100644 test/lib/initjmp.c
diff --git a/doc/api/setjmp.rst b/doc/api/setjmp.rst
index 7718047085c..c48b2e3e096 100644
--- a/doc/api/setjmp.rst
+++ b/doc/api/setjmp.rst
@@ -8,3 +8,13 @@ Long jump API
.. kernel-doc:: include/setjmp.h
:internal:
+
+Example
+-------
+
+Here is an example showing how to use the a long jump functions and
+initjmp() in particular:
+
+.. literalinclude:: ../../test/lib/initjmp.c
+ :language: c
+ :linenos:
diff --git a/test/lib/Makefile b/test/lib/Makefile
index 0e4cb8e3dfd..bf04685dae1 100644
--- a/test/lib/Makefile
+++ b/test/lib/Makefile
@@ -14,6 +14,7 @@ obj-y += hexdump.o
obj-$(CONFIG_SANDBOX) += kconfig.o
obj-y += lmb.o
obj-$(CONFIG_HAVE_SETJMP) += longjmp.o
+obj-$(CONFIG_HAVE_INITJMP) += initjmp.o
obj-$(CONFIG_CONSOLE_RECORD) += test_print.o
obj-$(CONFIG_SSCANF) += sscanf.o
obj-$(CONFIG_$(PHASE_)STRTO) += str.o
diff --git a/test/lib/initjmp.c b/test/lib/initjmp.c
new file mode 100644
index 00000000000..5b4b50b3f0f
--- /dev/null
+++ b/test/lib/initjmp.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2025 Linaro Limited
+ *
+ * Unit test for initjmp()
+ */
+
+#include <compiler.h>
+#include <setjmp.h>
+#include <stdbool.h>
+#include <test/lib.h>
+#include <test/ut.h>
+#include <vsprintf.h>
+
+static bool ep_entered;
+static jmp_buf return_buf;
+
+static void __noreturn entrypoint(void)
+{
+ ep_entered = true;
+
+ /* Jump back to the main routine */
+ longjmp(return_buf, 1);
+
+ /* Not reached */
+ panic("longjmp failed\n");
+}
+
+static int lib_initjmp(struct unit_test_state *uts)
+{
+ int ret;
+ void *stack;
+ jmp_buf buf;
+ /* Arbitrary but smaller values (< page size?) fail on SANDBOX */
+ size_t stack_sz = 8192;
+
+ (void)entrypoint;
+
+ ep_entered = false;
+
+ stack = malloc(stack_sz);
+ ut_assertnonnull(stack);
+
+ /*
+ * Prepare return_buf so that entrypoint may jump back just after the
+ * if()
+ */
+ if (!setjmp(return_buf)) {
+ /* return_buf initialized, entrypoint not yet called */
+
+ /*
+ * Prepare another jump buffer to jump into entrypoint with the
+ * given stack
+ */
+ ret = initjmp(buf, entrypoint, stack, stack_sz);
+ ut_assertok(ret);
+
+ /* Jump into entrypoint */
+ longjmp(buf, 1);
+ /*
+ * Not reached since entrypoint is expected to branch after
+ * the if()
+ */
+ ut_assert(false);
+ }
+
+ ut_assert(ep_entered);
+
+ free(stack);
+
+ return 0;
+}
+LIB_TEST(lib_initjmp, 0);
--
2.43.0
