OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

qtest: make QEMU our direct child process

Browse Source 
qtest_init() cannot use exec*p() to launch QEMU since the exec*p()
functions take an argument array while qtest_init() takes char
*extra_args.  Therefore we execute /bin/sh -c <command-line> and let the
shell parse the argument string.

This left /bin/sh as our child process and our child's child was QEMU.
We still want QEMU's pid so the -pidfile option was used to let QEMU
report its pid.

The pidfile needs to be unlinked when the test case exits or fails.  In
other words, the pidfile creates a new problem for us!

Simplify all this using the shell 'exec' command.  It allows us to
replace the /bin/sh process with QEMU.  Then we no longer need to use
-pidfile because we already know our fork child's pid.

Note: Yes, it seems silly to exec /bin/sh when we could just exec QEMU
directly.  But remember qtest_init() takes a single char *extra_args
command-line fragment instead of a real argv[] array, so we need
/bin/sh's argument parsing behavior.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2014-02-17 14:54:17 +01:00
parent 98f9e35bef
commit cef60c925c
1 changed files with 5 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
tests/libqtest.c
View File

@ -43,7 +43,7 @@ struct QTestState
int qmp_fd;
bool irq_level[MAX_IRQ];
GString *rx;
pid_t qemu_pid; /* QEMU process spawned by our child */
pid_t qemu_pid; /* our child QEMU process */
};
#define g_assert_no_errno(ret) do { \
@ -88,32 +88,14 @@ static int socket_accept(int sock)
return ret;
}
static pid_t read_pid_file(const char *pid_file)
{
FILE *f;
char buffer[1024];
pid_t pid = -1;
f = fopen(pid_file, "r");
if (f) {
if (fgets(buffer, sizeof(buffer), f)) {
pid = atoi(buffer);
}
fclose(f);
}
return pid;
}
QTestState *qtest_init(const char *extra_args)
{
QTestState *s;
int sock, qmpsock, i;
gchar *socket_path;
gchar *qmp_socket_path;
gchar *pid_file;
gchar *command;
const char *qemu_binary;
pid_t pid;
qemu_binary = getenv("QTEST_QEMU_BINARY");
g_assert(qemu_binary != NULL);
@ -122,22 +104,20 @@ QTestState *qtest_init(const char *extra_args)
socket_path = g_strdup_printf("/tmp/qtest-%d.sock", getpid());
qmp_socket_path = g_strdup_printf("/tmp/qtest-%d.qmp", getpid());
pid_file = g_strdup_printf("/tmp/qtest-%d.pid", getpid());
sock = init_socket(socket_path);
qmpsock = init_socket(qmp_socket_path);
pid = fork();
if (pid == 0) {
command = g_strdup_printf("%s "
s->qemu_pid = fork();
if (s->qemu_pid == 0) {
command = g_strdup_printf("exec %s "
"-qtest unix:%s,nowait "
"-qtest-log /dev/null "
"-qmp unix:%s,nowait "
"-pidfile %s "
"-machine accel=qtest "
"-display none "
"%s", qemu_binary, socket_path,
qmp_socket_path, pid_file,
qmp_socket_path,
extra_args ?: "");
execlp("/bin/sh", "sh", "-c", command, NULL);
exit(1);
@ -159,10 +139,6 @@ QTestState *qtest_init(const char *extra_args)
qtest_qmp_discard_response(s, "");
qtest_qmp_discard_response(s, "{ 'execute': 'qmp_capabilities' }");
s->qemu_pid = read_pid_file(pid_file);
unlink(pid_file);
g_free(pid_file);
if (getenv("QTEST_STOP")) {
kill(s->qemu_pid, SIGSTOP);
}