From: Yuri Pudgorodskiy <y...@virtuozzo.com>
Guest-exec rewriten in platform-independant style with glib spawn.
Child process is spawn asynchroneously and exit status can later
be picked up by guest-exec-status command.
stdin/stdout/stderr of the child now is redirected to /dev/null
Later we will add ability to specify stdin in guest-exec command
and to get collected stdout/stderr with guest-exec-status.
Signed-off-by: Yuri Pudgorodskiy <y...@virtuozzo.com>
Signed-off-by: Denis V. Lunev <d...@openvz.org>
CC: Michael Roth <mdr...@linux.vnet.ibm.com>
---
qga/commands.c | 188 +++++++++++++++++++++++++++++++++++++++++++++++++++
qga/qapi-schema.json | 62 +++++++++++++++++
2 files changed, 250 insertions(+)
diff --git a/qga/commands.c b/qga/commands.c
index 7834967..63a5aaf 100644
--- a/qga/commands.c
+++ b/qga/commands.c
@@ -70,3 +70,191 @@ struct GuestAgentInfo *qmp_guest_info(Error **errp)
qmp_for_each_command(qmp_command_info, info);
return info;
}
+
+struct GuestExecInfo {
+ GPid pid;
+ gint status;
+ bool finished;
+ QTAILQ_ENTRY(GuestExecInfo) next;
+};
+typedef struct GuestExecInfo GuestExecInfo;
+
+static struct {
+ QTAILQ_HEAD(, GuestExecInfo) processes;
+} guest_exec_state = {
+ .processes = QTAILQ_HEAD_INITIALIZER(guest_exec_state.processes),
+};
+
+static GuestExecInfo *guest_exec_info_add(GPid pid)
+{
+ GuestExecInfo *gei;
+
+ gei = g_new0(GuestExecInfo, 1);
+ gei->pid = pid;
+ QTAILQ_INSERT_TAIL(&guest_exec_state.processes, gei, next);
+
+ return gei;
+}
+
+static GuestExecInfo *guest_exec_info_find(GPid pid)
+{
+ GuestExecInfo *gei;
+
+ QTAILQ_FOREACH(gei, &guest_exec_state.processes, next) {
+ if (gei->pid == pid) {
+ return gei;
+ }
+ }
+
+ return NULL;
+}
+
+GuestExecStatus *qmp_guest_exec_status(int64_t pid, Error **err)
+{
+ GuestExecInfo *gei;
+ GuestExecStatus *ges;
+
+ slog("guest-exec-status called, pid: %u", (uint32_t)pid);
+
+ gei = guest_exec_info_find((GPid)pid);
+ if (gei == NULL) {
+ error_setg(err, QERR_INVALID_PARAMETER, "pid");
+ return NULL;
+ }
+
+ ges = g_new0(GuestExecStatus, 1);
+ ges->exited = gei->finished;
+
+ if (gei->finished) {
+ /* Glib has no portable way to parse exit status.
+ * On UNIX, we can get either exit code from normal termination
+ * or signal number.
+ * On Windows, it is either the same exit code or the exception
+ * value for an unhandled exception that caused the process
+ * to terminate.
+ * See MSDN for GetExitCodeProcess() and ntstatus.h for possible
+ * well-known codes, e.g. C0000005 ACCESS_DENIED - analog of SIGSEGV
+ * References:
+ *
https://msdn.microsoft.com/en-us/library/windows/desktop/ms683189(v=vs.85).aspx
+ * https://msdn.microsoft.com/en-us/library/aa260331(v=vs.60).aspx
+ */
+#ifdef G_OS_WIN32
+ /* Additionally WIN32 does not provide any additional information
+ * on whetherthe child exited or terminated via signal.
+ * We use this simple range check to distingish application exit code
+ * (usually value less then 256) and unhandled exception code with
+ * ntstatus (always value greater then 0xC0000005). */
+ if ((uint32_t)gei->status < 0xC0000000U) {
+ ges->has_exitcode = true;
+ ges->exiticode = gei->status;
+ } else {
+ ges->has_signal = true;
+ ges->signal = gei->status;
+ }
+#else
+ if (WIFEXITED(gei->status)) {
+ ges->has_exitcode = true;
+ ges->exitcode = WEXITSTATUS(gei->status);
+ } else if (WIFSIGNALED(gei->status)) {
+ ges->has_signal = true;
+ ges->signal = WTERMSIG(gei->status);
+ }
+#endif
+ QTAILQ_REMOVE(&guest_exec_state.processes, gei, next);
+ g_free(gei);
+ }
+
+ return ges;
+}
+
+/* Get environment variables or arguments array for execve(). */
+static char **guest_exec_get_args(const strList *entry, bool log)
+{
+ const strList *it;
+ int count = 1, i = 0; /* reserve for NULL terminator */
+ char **args;
+ char *str; /* for logging array of arguments */
+ size_t str_size = 1;
+
+ for (it = entry; it != NULL; it = it->next) {
+ count++;
+ str_size += 1 + strlen(it->value);
+ }
+
+ str = g_malloc(str_size);
+ *str = 0;
+ args = g_malloc(count * sizeof(char *));
+ for (it = entry; it != NULL; it = it->next) {
+ args[i++] = it->value;
+ pstrcat(str, str_size, it->value);
+ if (it->next) {
+ pstrcat(str, str_size, " ");
+ }
+ }
+ args[i] = NULL;
+
+ if (log) {
+ slog("guest-exec called: \"%s\"", str);
+ }
+ g_free(str);
+
+ return args;
+}
+
+static void guest_exec_child_watch(GPid pid, gint status, gpointer data)
+{
+ GuestExecInfo *gei = (GuestExecInfo *)data;
+
+ g_debug("guest_exec_child_watch called, pid: %u, status: %u",
+ (uint32_t)pid, (uint32_t)status);
+
+ gei->status = status;
+ gei->finished = true;
+
+ g_spawn_close_pid(pid);
+}
+
+GuestExec *qmp_guest_exec(const char *path,
+ bool has_arg, strList *arg,
+ bool has_env, strList *env,
+ bool has_inp_data, const char *inp_data,
+ bool has_capture_output, bool capture_output,
+ Error **err)
+{
+ GPid pid;
+ GuestExec *ge = NULL;
+ GuestExecInfo *gei;
+ char **argv, **envp;
+ strList arglist;
+ gboolean ret;
+ GError *gerr = NULL;
+
+ arglist.value = (char *)path;
+ arglist.next = has_arg ? arg : NULL;
+
+ argv = guest_exec_get_args(&arglist, true);
+ envp = guest_exec_get_args(has_env ? env : NULL, false);
+
+ ret = g_spawn_async_with_pipes(NULL, argv, envp,
+ G_SPAWN_SEARCH_PATH |
+ G_SPAWN_DO_NOT_REAP_CHILD |
+ G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL,
+ NULL, NULL, &pid, NULL, NULL, NULL, &gerr);
+ if (!ret) {
+ error_setg(err, QERR_QGA_COMMAND_FAILED, gerr->message);
+ g_error_free(gerr);
+ goto done;
+ }
+
+ ge = g_malloc(sizeof(*ge));
+ ge->pid = (int64_t)pid;
+
+ gei = guest_exec_info_add(pid);
+ g_child_watch_add(pid, guest_exec_child_watch, gei);
+
+done:
+ g_free(argv);
+ g_free(envp);
+
+ return ge;
+}
diff --git a/qga/qapi-schema.json b/qga/qapi-schema.json
index 82894c6..da6b64f 100644
--- a/qga/qapi-schema.json
+++ b/qga/qapi-schema.json
@@ -930,3 +930,65 @@
##
{ 'command': 'guest-get-memory-block-info',
'returns': 'GuestMemoryBlockInfo' }
+
+# @GuestExecStatus:
+#
+# @exited: true if process has already terminated.
+# @exitcode: #optional process exit code if it was normally terminated.
+# @signal: #optional signal number (linux) or unhandled exception code
+# (windows) if the process was abnormally terminated.
+# @out-data: #optional base64-encoded stdout of the process
+# @err-data: #optional base64-encoded stderr of the process
+# Note: @out-data and @err-data are present only
+# if 'capture-output' was specified for 'guest-exec'
+#
+# Since: 2.5
+##
+{ 'struct': 'GuestExecStatus',
+ 'data': { 'exited': 'bool', '*exitcode': 'int', '*signal': 'int',
+ '*out-data': 'str', '*err-data': 'str' }}
+##
+# @guest-exec-status
+#
+# Check status of process associated with PID retrieved via guest-exec.
+# Reap the process and associated metadata if it has exited.
+#
+# @pid: pid returned from guest-exec
+#
+# Returns: @GuestExecStatus on success.
+#
+# Since 2.3
+##
+{ 'command': 'guest-exec-status',
+ 'data': { 'pid': 'int' },
+ 'returns': 'GuestExecStatus' }
+
+##
+# @GuestExec:
+# @pid: pid of child process in guest OS
+#
+#Since: 2.5
+##
+{ 'struct': 'GuestExec',
+ 'data': { 'pid': 'int'} }
+
+##
+# @guest-exec:
+#
+# Execute a command in the guest
+#
+# @path: path or executable name to execute
+# @arg: #optional argument list to pass to executable
+# @env: #optional environment variables to pass to executable
+# @inp-data: #optional data to be passed to process stdin (base64 encoded)
+# @capture-output: #optional bool flags to enable capture of
+# stdout/stderr of running process
+#
+# Returns: PID on success.
+#
+# Since: 2.5
+##
+{ 'command': 'guest-exec',
+ 'data': { 'path': 'str', '*arg': ['str'], '*env': ['str'],
+ '*inp-data': 'str', '*capture-output': 'bool' },
+ 'returns': 'GuestExec' }
--
2.1.4
