[4/4] tests/tcg: Test shmat(NULL)

Commit Message

Ilya Leoshkevich March 25, 2024, 3:07 p.m. UTC

Add a small test to prevent regressions.

Signed-off-by: Ilya Leoshkevich <[e-mail]>
---
 tests/tcg/multiarch/linux/linux-shmat-null.c | 38 ++++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 tests/tcg/multiarch/linux/linux-shmat-null.c

Comments

Richard Henderson March 25, 2024, 6:35 p.m. UTC | #1

On 3/25/24 05:07, Ilya Leoshkevich wrote:
> Add a small test to prevent regressions.
> 
> Signed-off-by: Ilya Leoshkevich<[e-mail]>
> ---
>   tests/tcg/multiarch/linux/linux-shmat-null.c | 38 ++++++++++++++++++++
>   1 file changed, 38 insertions(+)
>   create mode 100644 tests/tcg/multiarch/linux/linux-shmat-null.c

Reviewed-by: Richard Henderson <[e-mail]>

r~

Patch

diff --git a/tests/tcg/multiarch/linux/linux-shmat-null.c b/tests/tcg/multiarch/linux/linux-shmat-null.c
new file mode 100644
index 00000000000..94eaaec371a
--- /dev/null
+++ b/tests/tcg/multiarch/linux/linux-shmat-null.c
@@ -0,0 +1,38 @@ 
+/*
+ * Test shmat(NULL).
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#include <assert.h>
+#include <stdlib.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+
+int main(void)
+{
+    int shmid;
+    char *p;
+    int err;
+
+    /* Create, attach and intialize shared memory. */
+    shmid = shmget(IPC_PRIVATE, 1, IPC_CREAT | 0600);
+    assert(shmid != -1);
+    p = shmat(shmid, NULL, 0);
+    assert(p != (void *)-1);
+    *p = 42;
+
+    /* Reattach, check that the value is still there. */
+    err = shmdt(p);
+    assert(err == 0);
+    p = shmat(shmid, NULL, 0);
+    assert(p != (void *)-1);
+    assert(*p == 42);
+
+    /* Detach. */
+    err = shmdt(p);
+    assert(err == 0);
+    err = shmctl(shmid, IPC_RMID, NULL);
+    assert(err == 0);
+
+    return EXIT_SUCCESS;
+}