journal: implement inotify-based live logging logic

[elogind.git] / src / util.c

diff --git a/src/util.c b/src/util.c
index a3cfe864b6e44c5cf38e04c7c0a18386be0364e4..37942de534708c407a4308118bf1d86c988cd23e 100644 (file)
--- a/src/util.c
+++ b/src/util.c
@@ -2336,8 +2336,10 @@ int chvt(int vt) {
                         0
                 };
 
-                if (ioctl(fd, TIOCLINUX, tiocl) < 0)
-                        return -errno;
+                if (ioctl(fd, TIOCLINUX, tiocl) < 0) {
+                        r = -errno;
+                        goto fail;
+                }
 
                 vt = tiocl[0] <= 0 ? 1 : tiocl[0];
         }
@@ -2345,7 +2347,8 @@ int chvt(int vt) {
         if (ioctl(fd, VT_ACTIVATE, vt) < 0)
                 r = -errno;
 
-        close_nointr_nofail(r);
+fail:
+        close_nointr_nofail(fd);
         return r;
 }
 
@@ -2671,7 +2674,7 @@ int acquire_terminal(const char *name, bool fail, bool force, bool ignore_tiocst
                         ssize_t l;
                         struct inotify_event *e;
 
-                        if ((l = read(notify, &inotify_buffer, sizeof(inotify_buffer))) < 0) {
+                        if ((l = read(notify, inotify_buffer, sizeof(inotify_buffer))) < 0) {
 
                                 if (errno == EINTR)
                                         continue;
@@ -5900,3 +5903,36 @@ int prot_from_flags(int flags) {
                 return -EINVAL;
         }
 }
+
+unsigned long cap_last_cap(void) {
+        static __thread unsigned long saved;
+        static __thread bool valid = false;
+        unsigned long p;
+
+        if (valid)
+                return saved;
+
+        p = (unsigned long) CAP_LAST_CAP;
+
+        if (prctl(PR_CAPBSET_READ, p) < 0) {
+
+                /* Hmm, look downwards, until we find one that
+                 * works */
+                for (p--; p > 0; p --)
+                        if (prctl(PR_CAPBSET_READ, p) >= 0)
+                                break;
+
+        } else {
+
+                /* Hmm, look upwards, until we find one that doesn't
+                 * work */
+                for (;; p++)
+                        if (prctl(PR_CAPBSET_READ, p+1) < 0)
+                                break;
+        }
+
+        saved = p;
+        valid = true;
+
+        return p;
+}