]> sigrok.org Git - libsigrok.git/blobdiff - src/session.c
USB: Handle live changes to the set of FDs to poll
[libsigrok.git] / src / session.c
index 849dc0d3bd0dd9b46ca03bf0c182e2a0f31a098f..0f4a0d70e82bf733d2cca1595b819c4c10ee0e9a 100644 (file)
@@ -526,8 +526,16 @@ static int sr_session_iteration(struct sr_session *session)
                 */
                sr_spew("callback for event source %" G_GINTPTR_FORMAT " with"
                        " event mask 0x%.2X", poll_object, (unsigned)revents);
-               if (!source->cb(fd, revents, source->cb_data))
-                       sr_session_source_remove_internal(session, poll_object);
+               if (!source->cb(fd, revents, source->cb_data)) {
+                       /* Hackish, to be cleaned up when porting to
+                        * the GLib main loop.
+                        */
+                       if (poll_object == (gintptr)session->ctx->libusb_ctx)
+                               usb_source_remove(session, session->ctx);
+                       else
+                               sr_session_source_remove_internal(session,
+                                               poll_object);
+               }
                /*
                 * We want to take as little time as possible to stop
                 * the session if we have been told to do so. Therefore,
@@ -902,8 +910,6 @@ SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
  * Add an event source for a file descriptor.
  *
  * @param session The session to use. Must not be NULL.
- * @param[in] pollfds The FDs to poll, or NULL if @a num_fds is 0.
- * @param[in] num_fds Number of FDs in the array.
  * @param[in] timeout Max time in ms to wait before the callback is called,
  *                    or -1 to wait indefinitely.
  * @param cb Callback function to add. Must not be NULL.
@@ -915,23 +921,17 @@ SR_PRIV int sr_session_send(const struct sr_dev_inst *sdi,
  * @retval SR_ERR An event source for @a poll_object is already installed.
  */
 SR_PRIV int sr_session_source_add_internal(struct sr_session *session,
-               const GPollFD *pollfds, int num_fds, int timeout,
-               sr_receive_data_callback cb, void *cb_data,
+               int timeout, sr_receive_data_callback cb, void *cb_data,
                gintptr poll_object)
 {
        struct source src;
        unsigned int i;
-       int k;
 
        /* Note: cb_data can be NULL, that's not a bug. */
        if (!cb) {
                sr_err("%s: cb was NULL", __func__);
                return SR_ERR_ARG;
        }
-       if (!pollfds && num_fds != 0) {
-               sr_err("%s: pollfds was NULL", __func__);
-               return SR_ERR_ARG;
-       }
        /* Make sure that poll_object is unique.
         */
        for (i = 0; i < session->sources->len; ++i) {
@@ -942,12 +942,12 @@ SR_PRIV int sr_session_source_add_internal(struct sr_session *session,
                        return SR_ERR;
                }
        }
-       sr_dbg("Installing event source %" G_GINTPTR_FORMAT " with %d FDs"
-               " and %d ms timeout.", poll_object, num_fds, timeout);
+       sr_dbg("Installing event source %" G_GINTPTR_FORMAT
+               " with %d ms timeout.", poll_object, timeout);
        src.cb = cb;
        src.cb_data = cb_data;
        src.poll_object = poll_object;
-       src.num_fds = num_fds;
+       src.num_fds = 0;
        src.triggered = FALSE;
 
        if (timeout >= 0) {
@@ -959,12 +959,56 @@ SR_PRIV int sr_session_source_add_internal(struct sr_session *session,
        }
        g_array_append_val(session->sources, src);
 
-       for (k = 0; k < num_fds; ++k) {
-               sr_dbg("Registering poll FD %" G_GINTPTR_FORMAT
-                       " with event mask 0x%.2X.",
-                       (gintptr)pollfds[k].fd, (unsigned)pollfds[k].events);
+       return SR_OK;
+}
+
+SR_PRIV int sr_session_source_poll_add(struct sr_session *session,
+               gintptr poll_object, gintptr fd, int events)
+{
+       struct source *source;
+       GPollFD pollfd;
+       unsigned int i;
+       int fd_index, k;
+
+       source = NULL;
+       fd_index = 0;
+
+       /* Look up existing event source.
+        */
+       for (i = 0; i < session->sources->len; ++i) {
+               source = &g_array_index(session->sources, struct source, i);
+               if (source->poll_object == poll_object)
+                       break;
+               fd_index += source->num_fds;
+       }
+       if (!source) {
+               sr_err("Cannot add poll FD %" G_GINTPTR_FORMAT
+                       " to non-existing event source %" G_GINTPTR_FORMAT
+                       ".",  fd, poll_object);
+               return SR_ERR;
        }
-       g_array_append_vals(session->pollfds, pollfds, num_fds);
+       /* Make sure the FD is unique.
+        */
+       for (k = 0; k < source->num_fds; ++k)
+               if (g_array_index(session->pollfds, GPollFD, fd_index + k)
+                               .fd == fd) {
+                       sr_err("Cannot add poll FD %" G_GINTPTR_FORMAT
+                               " twice to event source %" G_GINTPTR_FORMAT
+                               ".", fd, poll_object);
+                       return SR_ERR;
+               }
+
+       pollfd.fd = fd;
+       pollfd.events = events;
+       pollfd.revents = 0;
+
+       g_array_insert_val(session->pollfds,
+               fd_index + source->num_fds, pollfd);
+       ++source->num_fds;
+
+       sr_dbg("Added poll FD %" G_GINTPTR_FORMAT " with event mask 0x%.2X"
+               " to event source %" G_GINTPTR_FORMAT ".",
+               fd, (unsigned)events, poll_object);
 
        return SR_OK;
 }
@@ -973,7 +1017,7 @@ SR_PRIV int sr_session_source_add_internal(struct sr_session *session,
  * Add an event source for a file descriptor.
  *
  * @param session The session to use. Must not be NULL.
- * @param fd The file descriptor.
+ * @param fd The file descriptor, or a negative value to create a timer source.
  * @param events Events to check for.
  * @param timeout Max time in ms to wait before the callback is called,
  *                or -1 to wait indefinitely.
@@ -988,18 +1032,17 @@ SR_PRIV int sr_session_source_add_internal(struct sr_session *session,
 SR_API int sr_session_source_add(struct sr_session *session, int fd,
                int events, int timeout, sr_receive_data_callback cb, void *cb_data)
 {
-       GPollFD p;
+       int ret;
 
        if (fd < 0 && timeout < 0) {
                sr_err("Timer source without timeout would block indefinitely");
                return SR_ERR_ARG;
        }
-       p.fd = fd;
-       p.events = events;
-       p.revents = 0;
+       ret = sr_session_source_add_internal(session, timeout, cb, cb_data, fd);
+       if (ret != SR_OK || fd < 0)
+               return ret;
 
-       return sr_session_source_add_internal(session,
-               &p, (fd < 0) ? 0 : 1, timeout, cb, cb_data, fd);
+       return sr_session_source_poll_add(session, fd, fd, events);
 }
 
 /**
@@ -1021,12 +1064,19 @@ SR_API int sr_session_source_add_pollfd(struct sr_session *session,
                GPollFD *pollfd, int timeout, sr_receive_data_callback cb,
                void *cb_data)
 {
+       int ret;
+
        if (!pollfd) {
                sr_err("%s: pollfd was NULL", __func__);
                return SR_ERR_ARG;
        }
-       return sr_session_source_add_internal(session, pollfd, 1,
+       ret = sr_session_source_add_internal(session,
                        timeout, cb, cb_data, (gintptr)pollfd);
+       if (ret != SR_OK)
+               return ret;
+
+       return sr_session_source_poll_add(session,
+                       (gintptr)pollfd, pollfd->fd, pollfd->events);
 }
 
 /**
@@ -1049,17 +1099,22 @@ SR_API int sr_session_source_add_channel(struct sr_session *session,
                GIOChannel *channel, int events, int timeout,
                sr_receive_data_callback cb, void *cb_data)
 {
-       GPollFD p;
+       int ret;
 
+       ret = sr_session_source_add_internal(session,
+                       timeout, cb, cb_data, (gintptr)channel);
+       if (ret != SR_OK)
+               return ret;
 #ifdef G_OS_WIN32
+       GPollFD p;
        g_io_channel_win32_make_pollfd(channel, events, &p);
+
+       return sr_session_source_poll_add(session,
+                       (gintptr)channel, p.fd, p.events);
 #else
-       p.fd = g_io_channel_unix_get_fd(channel);
-       p.events = events;
-       p.revents = 0;
+       return sr_session_source_poll_add(session, (gintptr)channel,
+                       g_io_channel_unix_get_fd(channel), events);
 #endif
-       return sr_session_source_add_internal(session, &p, 1,
-                       timeout, cb, cb_data, (gintptr)channel);
 }
 
 /**
@@ -1108,6 +1163,52 @@ SR_PRIV int sr_session_source_remove_internal(struct sr_session *session,
        return SR_ERR_BUG;
 }
 
+SR_PRIV int sr_session_source_poll_remove(struct sr_session *session,
+               gintptr poll_object, gintptr fd)
+{
+       struct source *source;
+       unsigned int i;
+       int fd_index, k;
+
+       source = NULL;
+       fd_index = 0;
+
+       /* Look up existing event source.
+        */
+       for (i = 0; i < session->sources->len; ++i) {
+               source = &g_array_index(session->sources, struct source, i);
+               if (source->poll_object == poll_object)
+                       break;
+               fd_index += source->num_fds;
+       }
+       if (!source) {
+               sr_err("Cannot remove poll FD %" G_GINTPTR_FORMAT
+                       " from non-existing event source %" G_GINTPTR_FORMAT
+                       ".", fd, poll_object);
+               return SR_ERR;
+       }
+       /* Look up the FD in the poll set.
+        */
+       for (k = 0; k < source->num_fds; ++k)
+               if (g_array_index(session->pollfds, GPollFD, fd_index + k)
+                               .fd == fd) {
+
+                       g_array_remove_index(session->pollfds, fd_index + k);
+                       --source->num_fds;
+
+                       sr_dbg("Removed poll FD %" G_GINTPTR_FORMAT
+                               " from event source %" G_GINTPTR_FORMAT ".",
+                               fd, poll_object);
+                       return SR_OK;
+               }
+
+       sr_err("Cannot remove non-existing poll FD %" G_GINTPTR_FORMAT
+               " from event source %" G_GINTPTR_FORMAT ".",
+               fd, poll_object);
+
+       return SR_ERR;
+}
+
 /**
  * Remove the source belonging to the specified file descriptor.
  *