Hi Thomas, On Mon, 2023-07-31 at 08:10 +0200, Thomas Weißschuh wrote: > On 2023-07-31 13:51:00+0800, Yuan Tan wrote: > > Add a testcase of pipe that child process sends message to parent > > process. > > Thinking about it some more: > > What's the advantage of going via a child process? > The pipe should work the same within the same process. > The pipe is commonly used for process communication, and I think as a test case it is supposed to cover the most common scenarios. > > Here we use memcmp() to avoid the output buffer issue. > > This sentence is meaningless without the background from v1. > You can drop it. > Got it. > > Suggested-by: Thomas Weißschuh <thomas@xxxxxxxx> > > Suggested-by: Willy Tarreau <w@xxxxxx> > > Link: https://lore.kernel.org/all/c5de2d13-3752-4e1b-90d9-f58cca99c702@xxxxxxxx/ > > Signed-off-by: Yuan Tan <tanyuan@xxxxxxxxxxx> > > --- > > tools/testing/selftests/nolibc/nolibc-test.c | 35 ++++++++++++++++++++ > > 1 file changed, 35 insertions(+) > > > > diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c > > index 03b1d30f5507..2653ab8d5124 100644 > > --- a/tools/testing/selftests/nolibc/nolibc-test.c > > +++ b/tools/testing/selftests/nolibc/nolibc-test.c > > @@ -767,6 +767,41 @@ int test_mmap_munmap(void) > > return ret; > > } > > > > +int test_pipe(void) > > Should be static and actually get called :-) > > > +{ > > + const char *const msg = "hello, nolibc"; > > + int pipefd[2]; > > + char buf[32]; > > + pid_t pid; > > + ssize_t len; > > + > > + if (pipe(pipefd) == -1) > > + return 1; > > + > > + pid = fork(); > > + > > + switch (pid) { > > + case -1: > > + return 1; > > + > > + case 0: > > + close(pipefd[0]); > > + write(pipefd[1], msg, strlen(msg)); > > + close(pipefd[1]); > > + exit(EXIT_SUCCESS); > > + > > + default: > > + close(pipefd[1]); > > + len = read(pipefd[0], buf, sizeof(buf)); > > + close(pipefd[0]); > > + waitpid(pid, NULL, 0); > > + > > + if (len != strlen(msg)) > > + return 1; > > + return !!memcmp(buf, msg, len); > > + } > > +} > > + > > > > /* Run syscall tests between IDs <min> and <max>. > > * Return 0 on success, non-zero on failure. > > -- > > 2.34.1 > > >
