core: add support for naming file descriptors passed using socket activation

This adds support for naming file descriptors passed using socket
activation. The names are passed in a new $LISTEN_FDNAMES= environment
variable, that matches the existign $LISTEN_FDS= one and contains a
colon-separated list of names.

This also adds support for naming fds submitted to the per-service fd
store using FDNAME= in the sd_notify() message.

This also adds a new FileDescriptorName= setting for socket unit files
to set the name for fds created by socket units.

This also adds a new call sd_listen_fds_with_names(), that is similar to
sd_listen_fds(), but also returns the names of the fds.

systemd-activate gained the new --fdname= switch to specify a name for
testing socket activation.

This is based on #1247 by Maciej Wereski.

Fixes #1247.

1 files changed, 12 insertions, 1 deletions

diff --git a/src/core/execute.h b/src/core/execute.h
index 2c93044748..f1c37116fd 100644
--- a/src/core/execute.h
+++ b/src/core/execute.h
@@ -208,19 +208,30 @@ struct ExecContext {
 
 struct ExecParameters {
         char **argv;
-        int *fds; unsigned n_fds;
+
+        int *fds;
+        char **fd_names;
+        unsigned n_fds;
+
         char **environment;
+
         bool apply_permissions;
         bool apply_chroot;
         bool apply_tty_stdin;
+
         bool confirm_spawn;
         bool selinux_context_net;
+
         CGroupMask cgroup_supported;
         const char *cgroup_path;
         bool cgroup_delegate;
+
         const char *runtime_prefix;
+
         usec_t watchdog_usec;
+
         int *idle_pipe;
+
         char *bus_endpoint_path;
         int bus_endpoint_fd;
 };