i3
src/startup.c
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00001 /*
00002  * vim:ts=4:sw=4:expandtab
00003  *
00004  * i3 - an improved dynamic tiling window manager
00005  * © 2009-2012 Michael Stapelberg and contributors (see also: LICENSE)
00006  *
00007  * startup.c: Startup notification code. Ensures a startup notification context
00008  *            is setup when launching applications. We store the current
00009  *            workspace to open windows in that startup notification context on
00010  *            the appropriate workspace.
00011  *
00012  */
00013 #include "all.h"
00014 #include "sd-daemon.h"
00015 
00016 #include <sys/types.h>
00017 #include <sys/wait.h>
00018 
00019 #define SN_API_NOT_YET_FROZEN 1
00020 #include <libsn/sn-launcher.h>
00021 
00022 static TAILQ_HEAD(startup_sequence_head, Startup_Sequence) startup_sequences =
00023     TAILQ_HEAD_INITIALIZER(startup_sequences);
00024 
00025 /*
00026  * After 60 seconds, a timeout will be triggered for each startup sequence.
00027  *
00028  * The timeout will just trigger completion of the sequence, so the normal
00029  * completion process takes place (startup_monitor_event will free it).
00030  *
00031  */
00032 static void startup_timeout(EV_P_ ev_timer *w, int revents) {
00033     const char *id = sn_launcher_context_get_startup_id(w->data);
00034     DLOG("Timeout for startup sequence %s\n", id);
00035 
00036     struct Startup_Sequence *current, *sequence = NULL;
00037     TAILQ_FOREACH(current, &startup_sequences, sequences) {
00038         if (strcmp(current->id, id) != 0)
00039             continue;
00040 
00041         sequence = current;
00042         break;
00043     }
00044 
00045     /* Unref the context (for the timeout itself, see start_application) */
00046     sn_launcher_context_unref(w->data);
00047 
00048     if (!sequence) {
00049         DLOG("Sequence already deleted, nevermind.\n");
00050         return;
00051     }
00052 
00053     /* Complete the startup sequence, will trigger its deletion. */
00054     sn_launcher_context_complete(w->data);
00055     free(w);
00056 }
00057 
00058 /*
00059  * Starts the given application by passing it through a shell. We use double fork
00060  * to avoid zombie processes. As the started application’s parent exits (immediately),
00061  * the application is reparented to init (process-id 1), which correctly handles
00062  * childs, so we don’t have to do it :-).
00063  *
00064  * The shell is determined by looking for the SHELL environment variable. If it
00065  * does not exist, /bin/sh is used.
00066  *
00067  * The no_startup_id flag determines whether a startup notification context
00068  * (and ID) should be created, which is the default and encouraged behavior.
00069  *
00070  */
00071 void start_application(const char *command, bool no_startup_id) {
00072     SnLauncherContext *context;
00073 
00074     if (!no_startup_id) {
00075         /* Create a startup notification context to monitor the progress of this
00076          * startup. */
00077         context = sn_launcher_context_new(sndisplay, conn_screen);
00078         sn_launcher_context_set_name(context, "i3");
00079         sn_launcher_context_set_description(context, "exec command in i3");
00080         /* Chop off everything starting from the first space (if there are any
00081          * spaces in the command), since we don’t want the parameters. */
00082         char *first_word = sstrdup(command);
00083         char *space = strchr(first_word, ' ');
00084         if (space)
00085             *space = '\0';
00086         sn_launcher_context_initiate(context, "i3", first_word, last_timestamp);
00087         free(first_word);
00088 
00089         /* Trigger a timeout after 60 seconds */
00090         struct ev_timer *timeout = scalloc(sizeof(struct ev_timer));
00091         ev_timer_init(timeout, startup_timeout, 60.0, 0.);
00092         timeout->data = context;
00093         ev_timer_start(main_loop, timeout);
00094 
00095         LOG("startup id = %s\n", sn_launcher_context_get_startup_id(context));
00096 
00097         /* Save the ID and current workspace in our internal list of startup
00098          * sequences */
00099         Con *ws = con_get_workspace(focused);
00100         struct Startup_Sequence *sequence = scalloc(sizeof(struct Startup_Sequence));
00101         sequence->id = sstrdup(sn_launcher_context_get_startup_id(context));
00102         sequence->workspace = sstrdup(ws->name);
00103         sequence->context = context;
00104         TAILQ_INSERT_TAIL(&startup_sequences, sequence, sequences);
00105 
00106         /* Increase the refcount once (it starts with 1, so it will be 2 now) for
00107          * the timeout. Even if the sequence gets completed, the timeout still
00108          * needs the context (but will unref it then) */
00109         sn_launcher_context_ref(context);
00110     }
00111 
00112     LOG("executing: %s\n", command);
00113     if (fork() == 0) {
00114         /* Child process */
00115         setsid();
00116         setrlimit(RLIMIT_CORE, &original_rlimit_core);
00117         /* Close all socket activation file descriptors explicitly, we disabled
00118          * FD_CLOEXEC to keep them open when restarting i3. */
00119         for (int fd = SD_LISTEN_FDS_START;
00120              fd < (SD_LISTEN_FDS_START + listen_fds);
00121              fd++) {
00122             close(fd);
00123         }
00124         unsetenv("LISTEN_PID");
00125         unsetenv("LISTEN_FDS");
00126         if (fork() == 0) {
00127             /* Setup the environment variable(s) */
00128             if (!no_startup_id)
00129                 sn_launcher_context_setup_child_process(context);
00130 
00131             /* Stores the path of the shell */
00132             static const char *shell = NULL;
00133 
00134             if (shell == NULL)
00135                 if ((shell = getenv("SHELL")) == NULL)
00136                     shell = "/bin/sh";
00137 
00138             /* This is the child */
00139             execl(shell, shell, "-c", command, (void*)NULL);
00140             /* not reached */
00141         }
00142         _exit(0);
00143     }
00144     wait(0);
00145 
00146     if (!no_startup_id) {
00147         /* Change the pointer of the root window to indicate progress */
00148         if (xcursor_supported)
00149             xcursor_set_root_cursor(XCURSOR_CURSOR_WATCH);
00150         else xcb_set_root_cursor(XCURSOR_CURSOR_WATCH);
00151     }
00152 }
00153 
00154 /*
00155  * Called by libstartup-notification when something happens
00156  *
00157  */
00158 void startup_monitor_event(SnMonitorEvent *event, void *userdata) {
00159     SnStartupSequence *snsequence;
00160 
00161     snsequence = sn_monitor_event_get_startup_sequence(event);
00162 
00163     /* Get the corresponding internal startup sequence */
00164     const char *id = sn_startup_sequence_get_id(snsequence);
00165     struct Startup_Sequence *current, *sequence = NULL;
00166     TAILQ_FOREACH(current, &startup_sequences, sequences) {
00167         if (strcmp(current->id, id) != 0)
00168             continue;
00169 
00170         sequence = current;
00171         break;
00172     }
00173 
00174     if (!sequence) {
00175         DLOG("Got event for startup sequence that we did not initiate (ID = %s). Ignoring.\n", id);
00176         return;
00177     }
00178 
00179     switch (sn_monitor_event_get_type(event)) {
00180         case SN_MONITOR_EVENT_COMPLETED:
00181             DLOG("startup sequence %s completed\n", sn_startup_sequence_get_id(snsequence));
00182 
00183             /* Unref the context, will be free()d */
00184             sn_launcher_context_unref(sequence->context);
00185 
00186             /* Delete our internal sequence */
00187             TAILQ_REMOVE(&startup_sequences, sequence, sequences);
00188 
00189             if (TAILQ_EMPTY(&startup_sequences)) {
00190                 DLOG("No more startup sequences running, changing root window cursor to default pointer.\n");
00191                 /* Change the pointer of the root window to indicate progress */
00192                 if (xcursor_supported)
00193                     xcursor_set_root_cursor(XCURSOR_CURSOR_POINTER);
00194                 else xcb_set_root_cursor(XCURSOR_CURSOR_POINTER);
00195             }
00196             break;
00197         default:
00198             /* ignore */
00199             break;
00200     }
00201 }
00202 
00203 /*
00204  * Checks if the given window belongs to a startup notification by checking if
00205  * the _NET_STARTUP_ID property is set on the window (or on its leader, if it’s
00206  * unset).
00207  *
00208  * If so, returns the workspace on which the startup was initiated.
00209  * Returns NULL otherwise.
00210  *
00211  */
00212 char *startup_workspace_for_window(i3Window *cwindow, xcb_get_property_reply_t *startup_id_reply) {
00213     /* The _NET_STARTUP_ID is only needed during this function, so we get it
00214      * here and don’t save it in the 'cwindow'. */
00215     if (startup_id_reply == NULL || xcb_get_property_value_length(startup_id_reply) == 0) {
00216         FREE(startup_id_reply);
00217         DLOG("No _NET_STARTUP_ID set on this window\n");
00218         if (cwindow->leader == XCB_NONE)
00219             return NULL;
00220 
00221         xcb_get_property_cookie_t cookie;
00222         cookie = xcb_get_property(conn, false, cwindow->leader, A__NET_STARTUP_ID, XCB_GET_PROPERTY_TYPE_ANY, 0, 512);
00223         DLOG("Checking leader window 0x%08x\n", cwindow->leader);
00224         startup_id_reply = xcb_get_property_reply(conn, cookie, NULL);
00225 
00226         if (startup_id_reply == NULL || xcb_get_property_value_length(startup_id_reply) == 0) {
00227             DLOG("No _NET_STARTUP_ID set on the leader either\n");
00228             FREE(startup_id_reply);
00229             return NULL;
00230         }
00231     }
00232 
00233     char *startup_id;
00234     if (asprintf(&startup_id, "%.*s", xcb_get_property_value_length(startup_id_reply),
00235                  (char*)xcb_get_property_value(startup_id_reply)) == -1) {
00236         perror("asprintf()");
00237         DLOG("Could not get _NET_STARTUP_ID\n");
00238         free(startup_id_reply);
00239         return NULL;
00240     }
00241 
00242     struct Startup_Sequence *current, *sequence = NULL;
00243     TAILQ_FOREACH(current, &startup_sequences, sequences) {
00244         if (strcmp(current->id, startup_id) != 0)
00245             continue;
00246 
00247         sequence = current;
00248         break;
00249     }
00250 
00251     free(startup_id);
00252     free(startup_id_reply);
00253 
00254     if (!sequence) {
00255         DLOG("WARNING: This sequence (ID %s) was not found\n", startup_id);
00256         return NULL;
00257     }
00258 
00259     return sequence->workspace;
00260 }