Merge pull request #17344 from keszybz/bus-connect-more-logs

Add some debug logs to help diagnose bus connections

src/libsystemd/sd-bus/bus-container.c

@@ -9,6 +9,7 @@
 #include "fd-util.h"
 #include "namespace-util.h"
 #include "process-util.h"
+#include "string-util.h"
 #include "util.h"
 
 int bus_container_connect_socket(sd_bus *b) {
@@ -24,10 +25,15 @@ int bus_container_connect_socket(sd_bus *b) {
         assert(b->nspid > 0 || b->machine);
 
         if (b->nspid <= 0) {
+                log_debug("sd-bus: connecting bus%s%s to machine %s...",
+                          b->description ? " " : "", strempty(b->description), b->machine);
+
                 r = container_get_leader(b->machine, &b->nspid);
                 if (r < 0)
                         return r;
-        }
+        } else
+                log_debug("sd-bus: connecting bus%s%s to namespace of PID "PID_FMT"...",
+                          b->description ? " " : "", strempty(b->description), b->nspid);
 
         r = namespace_open(b->nspid, &pidnsfd, &mntnsfd, NULL, &usernsfd, &rootfd);
         if (r < 0)

src/libsystemd/sd-bus/bus-socket.c

@@ -885,6 +885,13 @@ int bus_socket_connect(sd_bus *b) {
                 assert(b->output_fd < 0);
                 assert(b->sockaddr.sa.sa_family != AF_UNSPEC);
 
+                if (DEBUG_LOGGING) {
+                        _cleanup_free_ char *pretty = NULL;
+                        (void) sockaddr_pretty(&b->sockaddr.sa, b->sockaddr_size, false, true, &pretty);
+                        log_debug("sd-bus: starting bus%s%s by connecting to %s...",
+                                  b->description ? " " : "", strempty(b->description), strnull(pretty));
+                }
+
                 b->input_fd = socket(b->sockaddr.sa.sa_family, SOCK_STREAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
                 if (b->input_fd < 0)
                         return -errno;
@@ -956,6 +963,9 @@ int bus_socket_exec(sd_bus *b) {
         assert(b->exec_path);
         assert(b->busexec_pid == 0);
 
+        log_debug("sd-bus: starting bus%s%s with %s...",
+                  b->description ? " " : "", strempty(b->description), b->exec_path);
+
         r = socketpair(AF_UNIX, SOCK_STREAM|SOCK_NONBLOCK|SOCK_CLOEXEC, 0, s);
         if (r < 0)
                 return -errno;

src/libsystemd/sd-bus/sd-bus.c

@@ -1155,6 +1155,16 @@ static int bus_start_fd(sd_bus *b) {
         assert(b->input_fd >= 0);
         assert(b->output_fd >= 0);
 
+        if (DEBUG_LOGGING) {
+                _cleanup_free_ char *pi = NULL, *po = NULL;
+                (void) fd_get_path(b->input_fd, &pi);
+                (void) fd_get_path(b->output_fd, &po);
+                log_debug("sd-bus: starting bus%s%s on fds %d/%d (%s, %s)...",
+                          b->description ? " " : "", strempty(b->description),
+                          b->input_fd, b->output_fd,
+                          pi ?: "???", po ?: "???");
+        }
+
         r = fd_nonblock(b->input_fd, true);
         if (r < 0)
                 return r;
@@ -1330,7 +1340,8 @@ int bus_set_address_user(sd_bus *b) {
 
                 e = secure_getenv("XDG_RUNTIME_DIR");
                 if (!e)
-                        return -ENOENT;
+                        return log_debug_errno(SYNTHETIC_ERRNO(ENOMEDIUM),
+                                               "sd-bus: $XDG_RUNTIME_DIR not set, cannot connect to user bus.");
 
                 ee = bus_address_escape(e);
                 if (!ee)

src/libsystemd/sd-bus/test-bus-cleanup.c

@@ -23,7 +23,7 @@ static int test_bus_open(void) {
         int r;
 
         r = sd_bus_open_user(&bus);
-        if (IN_SET(r, -ECONNREFUSED, -ENOENT)) {
+        if (IN_SET(r, -ECONNREFUSED, -ENOENT, -ENOMEDIUM)) {
                 r = sd_bus_open_system(&bus);
                 if (IN_SET(r, -ECONNREFUSED, -ENOENT))
                         return r;

src/libsystemd/sd-bus/test-bus-track.c

@@ -55,7 +55,7 @@ int main(int argc, char *argv[]) {
         assert_se(r >= 0);
 
         r = sd_bus_open_user(&a);
-        if (IN_SET(r, -ECONNREFUSED, -ENOENT)) {
+        if (IN_SET(r, -ECONNREFUSED, -ENOENT, -ENOMEDIUM)) {
                 r = sd_bus_open_system(&a);
                 if (IN_SET(r, -ECONNREFUSED, -ENOENT))
                         return log_tests_skipped("Failed to connect to bus");