From: Sven Eden <yamakuzure@gmx.net>
Date: Wed, 13 Dec 2017 18:21:30 +0000 (+0100)
Subject: Prep 235: Implement an alternative approach for sd_pid_get_owner_uid(), making test... 
X-Git-Tag: v235.1~14
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=6ce305d6240b20ff7be3d75264f2d5a33be04e85;p=elogind.git

Prep 235: Implement an alternative approach for sd_pid_get_owner_uid(), making test-login to no longer fail.
---

diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index 9b4a56085..c4aec37ff 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -1811,8 +1811,8 @@ int cg_pid_get_session(pid_t pid, char **session) {
         return cg_path_get_session(cgroup, session);
 }
 
-#if 0 /// UNNEEDED by elogind
 int cg_path_get_owner_uid(const char *path, uid_t *uid) {
+#if 0 /// elogind does not support systemd slices
         _cleanup_free_ char *slice = NULL;
         char *start, *end;
         int r;
@@ -1835,6 +1835,34 @@ int cg_path_get_owner_uid(const char *path, uid_t *uid) {
                 return -ENXIO;
 
         return 0;
+#else
+        _cleanup_free_ char *p = NULL, *s = NULL;
+        char *start;
+        int r;
+
+        assert(path);
+
+        /* Basically this is a simple session->uid mapping here.
+           The path argument will be something like "/<session id>"
+           and that is something we can map.
+        */
+
+        start = startswith(path, "/");
+        if (start)
+                p = strappend("/run/systemd/sessions/", start);
+        else
+                p = strappend("/run/systemd/sessions/", path);
+
+        r = parse_env_file(p, NEWLINE, "UID", &s, NULL);
+        if (r == -ENOENT)
+                return -ENXIO;
+        if (r < 0)
+                return r;
+        if (isempty(s))
+                return -EIO;
+
+        return parse_uid(s, uid);
+#endif // 0
 }
 
 int cg_pid_get_owner_uid(pid_t pid, uid_t *uid) {
@@ -1848,6 +1876,7 @@ int cg_pid_get_owner_uid(pid_t pid, uid_t *uid) {
         return cg_path_get_owner_uid(cgroup, uid);
 }
 
+#if 0 /// UNNEEDED by elogind
 int cg_path_get_slice(const char *p, char **slice) {
         const char *e = NULL;
 
diff --git a/src/basic/cgroup-util.h b/src/basic/cgroup-util.h
index 1f1a33873..e8423dd0d 100644
--- a/src/basic/cgroup-util.h
+++ b/src/basic/cgroup-util.h
@@ -206,8 +206,8 @@ int cg_is_empty_recursive(const char *controller, const char *path);
 int cg_get_root_path(char **path);
 
 int cg_path_get_session(const char *path, char **session);
-#if 0 /// UNNEEDED by elogind
 int cg_path_get_owner_uid(const char *path, uid_t *uid);
+#if 0 /// UNNEEDED by elogind
 int cg_path_get_unit(const char *path, char **unit);
 int cg_path_get_user_unit(const char *path, char **unit);
 int cg_path_get_machine_name(const char *path, char **machine);
@@ -219,8 +219,8 @@ int cg_shift_path(const char *cgroup, const char *cached_root, const char **shif
 int cg_pid_get_path_shifted(pid_t pid, const char *cached_root, char **cgroup);
 
 int cg_pid_get_session(pid_t pid, char **session);
-#if 0 /// UNNEEDED by elogind
 int cg_pid_get_owner_uid(pid_t pid, uid_t *uid);
+#if 0 /// UNNEEDED by elogind
 int cg_pid_get_unit(pid_t pid, char **unit);
 int cg_pid_get_user_unit(pid_t pid, char **unit);
 int cg_pid_get_machine_name(pid_t pid, char **machine);
diff --git a/src/libelogind/sd-login/sd-login.c b/src/libelogind/sd-login/sd-login.c
index 7859f1c47..91b3d1243 100644
--- a/src/libelogind/sd-login/sd-login.c
+++ b/src/libelogind/sd-login/sd-login.c
@@ -146,19 +146,13 @@ _public_ int sd_pid_get_user_slice(pid_t pid, char **slice) {
 }
 
 _public_ int sd_pid_get_owner_uid(pid_t pid, uid_t *uid) {
-#if 0 /// UNNEEDED by elogind
         int r;
-#endif // 0
 
         assert_return(pid >= 0, -EINVAL);
         assert_return(uid, -EINVAL);
 
-#if 0 /// elogind does not support systemd slices
         r = cg_pid_get_owner_uid(pid, uid);
         return IN_SET(r, -ENXIO, -ENOMEDIUM) ? -ENODATA : r;
-#else
-        return -ESRCH;
-#endif // 0
 }
 
 _public_ int sd_pid_get_cgroup(pid_t pid, char **cgroup) {