tests/boot-serial-test: Fix problem with timeout due to dropped characters

Commit 92b540dac9 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: 92b540dac9
Signed-off-by: Thomas Huth <thuth@redhat.com>
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 <peter.maydell@linaro.org>
This commit is contained in:
Thomas Huth 2018-02-16 07:12:44 +01:00 committed by Peter Maydell
parent cc5a0ae03e
commit 5e5432b766
1 changed files with 2 additions and 2 deletions

View File

@ -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') {