From 5afc7d5b77f92973f323f73eae9b55c5efa3d4a3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marco=20Trevisan=20=28Trevi=C3=B1o=29?= Date: Mon, 22 Nov 2021 16:55:35 +0100 Subject: [PATCH] gtestdbus: Print the dbus address on a specific FD intead of stdout We used to use a pipe for the dbus daemon stdout to read the defined address, but that was already requiring a workaround to ensure that dbus daemon children were then able to write to stdout. However the current implementation is still causing troubles in some cases in which the daemon is very verbose, leading to hangs when writing to stdout. As per this, just don't handle stdout ourself, but use instead a specific pipe to get the address address. That can now be safely closed once we've received the data we need. This reverts commit d80adeaa960ddfa13837900d0391f9bd9c239f78. Fixes: #2537 --- gio/gtestdbus.c | 89 ++++++++++++++++++++++++++++++++----------------- 1 file changed, 59 insertions(+), 30 deletions(-) diff --git a/gio/gtestdbus.c b/gio/gtestdbus.c index 703a0b3a5..992d29cef 100644 --- a/gio/gtestdbus.c +++ b/gio/gtestdbus.c @@ -32,6 +32,8 @@ #endif #ifdef G_OS_WIN32 #include +#include +#include #endif #include @@ -44,8 +46,8 @@ #include "glibintl.h" -#ifdef G_OS_WIN32 -#include +#ifdef G_OS_UNIX +#include "glib-unix.h" #endif /* -------------------------------------------------------------------------- */ @@ -436,7 +438,6 @@ struct _GTestDBusPrivate GTestDBusFlags flags; GPtrArray *service_dirs; GPid bus_pid; - gint bus_stdout_fd; gchar *bus_address; gboolean up; }; @@ -596,58 +597,87 @@ write_config_file (GTestDBus *self) return path; } +static gboolean +make_pipe (gint pipe_fds[2], + GError **error) +{ +#if defined(G_OS_UNIX) + return g_unix_open_pipe (pipe_fds, FD_CLOEXEC, error); +#elif defined(G_OS_WIN32) + if (_pipe (pipe_fds, 4096, _O_BINARY) < 0) + { + int errsv = errno; + + g_set_error (error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED, + _("Failed to create pipe for communicating with child process (%s)"), + g_strerror (errsv)); + return FALSE; + } + return TRUE; +#else + g_set_error (error, G_SPAWN_ERROR, G_SPAWN_ERROR_FAILED, + _("Pipes are not supported in this platform")); + return FALSE; +#endif +} + static void start_daemon (GTestDBus *self) { const gchar *argv[] = {"dbus-daemon", "--print-address", "--config-file=foo", NULL}; + gint pipe_fds[2] = {-1, -1}; gchar *config_path; gchar *config_arg; + gchar *print_address; GIOChannel *channel; - gint stdout_fd2; gsize termpos; GError *error = NULL; if (g_getenv ("G_TEST_DBUS_DAEMON") != NULL) argv[0] = (gchar *)g_getenv ("G_TEST_DBUS_DAEMON"); + make_pipe (pipe_fds, &error); + g_assert_no_error (error); + + print_address = g_strdup_printf ("--print-address=%d", pipe_fds[1]); + argv[1] = print_address; + g_assert_no_error (error); + /* Write config file and set its path in argv */ config_path = write_config_file (self); config_arg = g_strdup_printf ("--config-file=%s", config_path); argv[2] = config_arg; /* Spawn dbus-daemon */ - g_spawn_async_with_pipes (NULL, - (gchar **) argv, - NULL, - /* We Need this to get the pid returned on win32 */ - G_SPAWN_DO_NOT_REAP_CHILD | - G_SPAWN_SEARCH_PATH | - /* dbus-daemon will not abuse our descriptors, and - * passing this means we can use posix_spawn() for speed */ - G_SPAWN_LEAVE_DESCRIPTORS_OPEN, - NULL, - NULL, - &self->priv->bus_pid, - NULL, - &self->priv->bus_stdout_fd, - NULL, - &error); + g_spawn_async_with_pipes_and_fds (NULL, + argv, + NULL, + /* We Need this to get the pid returned on win32 */ + G_SPAWN_DO_NOT_REAP_CHILD | + G_SPAWN_SEARCH_PATH | + /* dbus-daemon will not abuse our descriptors, and + * passing this means we can use posix_spawn() for speed */ + G_SPAWN_LEAVE_DESCRIPTORS_OPEN, + NULL, NULL, + -1, -1, -1, + &pipe_fds[1], &pipe_fds[1], 1, + &self->priv->bus_pid, + NULL, NULL, NULL, + &error); g_assert_no_error (error); _g_test_watcher_add_pid (self->priv->bus_pid); - /* Read bus address from daemon' stdout. We have to be careful to avoid - * closing the FD, as it is passed to any D-Bus service activated processes, - * and if we close it, they will get a SIGPIPE and die when they try to write - * to their stdout. */ - stdout_fd2 = dup (self->priv->bus_stdout_fd); - g_assert_cmpint (stdout_fd2, >=, 0); - channel = g_io_channel_unix_new (stdout_fd2); - + /* Read bus address from pipe */ + channel = g_io_channel_unix_new (pipe_fds[0]); + pipe_fds[0] = -1; + g_io_channel_set_close_on_unref (channel, TRUE); g_io_channel_read_line (channel, &self->priv->bus_address, NULL, &termpos, &error); g_assert_no_error (error); self->priv->bus_address[termpos] = '\0'; + close (pipe_fds[1]); + pipe_fds[1] = -1; /* start dbus-monitor */ if (g_getenv ("G_DBUS_MONITOR") != NULL) @@ -671,6 +701,7 @@ start_daemon (GTestDBus *self) if (g_unlink (config_path) != 0) g_assert_not_reached (); + g_free (print_address); g_free (config_path); g_free (config_arg); } @@ -687,8 +718,6 @@ stop_daemon (GTestDBus *self) _g_test_watcher_remove_pid (self->priv->bus_pid); g_spawn_close_pid (self->priv->bus_pid); self->priv->bus_pid = 0; - close (self->priv->bus_stdout_fd); - self->priv->bus_stdout_fd = -1; g_free (self->priv->bus_address); self->priv->bus_address = NULL;