1 /*-
2 * Copyright (c) 2025 Raptor Computing Systems, LLC
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <ucontext.h>
10 #include <errno.h>
11
12 #include <atf-c.h>
13
14 #define STACK_SIZE (64ull << 10)
15
16 static volatile int callback_reached = 0;
17
18 static ucontext_t uctx_save, uctx_switch;
19
swapcontext_callback()20 static void swapcontext_callback()
21 {
22 // Increment callback reached variable
23 // If this is called multiple times, we will fail the test
24 // If this is not called at all, we will fail the test
25 callback_reached++;
26 }
27
28 ATF_TC(swapcontext_basic);
ATF_TC_HEAD(swapcontext_basic,tc)29 ATF_TC_HEAD(swapcontext_basic, tc)
30 {
31 atf_tc_set_md_var(tc, "descr",
32 "Verify basic functionality of swapcontext");
33 }
34
ATF_TC_BODY(swapcontext_basic,tc)35 ATF_TC_BODY(swapcontext_basic, tc)
36 {
37 char *stack;
38 int res;
39
40 stack = malloc(STACK_SIZE);
41 ATF_REQUIRE_MSG(stack != NULL, "malloc failed: %s", strerror(errno));
42 res = getcontext(&uctx_switch);
43 ATF_REQUIRE_MSG(res == 0, "getcontext failed: %s", strerror(errno));
44
45 uctx_switch.uc_stack.ss_sp = stack;
46 uctx_switch.uc_stack.ss_size = STACK_SIZE;
47 uctx_switch.uc_link = &uctx_save;
48 makecontext(&uctx_switch, swapcontext_callback, 0);
49
50 res = swapcontext(&uctx_save, &uctx_switch);
51
52 ATF_REQUIRE_MSG(res == 0, "swapcontext failed: %s", strerror(errno));
53 ATF_REQUIRE_MSG(callback_reached == 1,
54 "callback failed, reached %d times", callback_reached);
55 }
56
ATF_TP_ADD_TCS(tp)57 ATF_TP_ADD_TCS(tp)
58 {
59 ATF_TP_ADD_TC(tp, swapcontext_basic);
60
61 return (atf_no_error());
62 }
63
64