From 5e5432b766c424a5d1e1b81315ce6ac1dc0fa3ed Mon Sep 17 00:00:00 2001 From: Thomas Huth Date: Fri, 16 Feb 2018 07:12:44 +0100 Subject: [PATCH] tests/boot-serial-test: Fix problem with timeout due to dropped characters Commit 92b540dac9fc3a5 introduce a counter to handle the timeouts in a better way. But in case ccnt reaches 512, the current read character is ignored - and if that character is part of the string that we are looking for, the test fails to match the string. Almost all of the tests look for a string within the first 512 bytes of firmware output, so the problem never triggered there. But the hppa test that has been added recently looks for a longer string at the very end of a long output, thus there's a chance that we miss a character there so that the test fails unexpectedly. Fix it by *not* reading and dropping a character if the counter reaches 512. Fixes: 92b540dac9fc3a572c7342edd0b073000f5a6abf Signed-off-by: Thomas Huth Message-id: 1518761564-9899-1-git-send-email-thuth@redhat.com [PMM: added initializer for nbd to silence false-positive warning from OpenBSD 6 compiler] Signed-off-by: Peter Maydell --- tests/boot-serial-test.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tests/boot-serial-test.c b/tests/boot-serial-test.c index 511bf314a3..ece25c694f 100644 --- a/tests/boot-serial-test.c +++ b/tests/boot-serial-test.c @@ -111,13 +111,13 @@ static testdef_t tests[] = { static void check_guest_output(const testdef_t *test, int fd) { bool output_ok = false; - int i, nbr, pos = 0, ccnt; + int i, nbr = 0, pos = 0, ccnt; char ch; /* Poll serial output... Wait at most 60 seconds */ for (i = 0; i < 6000; ++i) { ccnt = 0; - while ((nbr = read(fd, &ch, 1)) == 1 && ccnt++ < 512) { + while (ccnt++ < 512 && (nbr = read(fd, &ch, 1)) == 1) { if (ch == test->expect[pos]) { pos += 1; if (test->expect[pos] == '\0') {