util: fix error checking after fgets()

[elogind.git] / src / util.c

diff --git a/src/util.c b/src/util.c
index e46606dabb39551e0b0b5b3df5a39ef311ee861b..da71e4d08b270a8da6c9d7a347f8cbb33ef451b0 100644 (file)
--- a/src/util.c
+++ b/src/util.c
@@ -516,7 +516,7 @@ int get_parent_of_pid(pid_t pid, pid_t *_ppid) {
                 return -errno;
 
         if (!(fgets(line, sizeof(line), f))) {
-                r = -errno;
+                r = feof(f) ? -EIO : -errno;
                 fclose(f);
                 return r;
         }
@@ -561,7 +561,7 @@ int get_starttime_of_pid(pid_t pid, unsigned long long *st) {
                 return -errno;
 
         if (!(fgets(line, sizeof(line), f))) {
-                r = -errno;
+                r = feof(f) ? -EIO : -errno;
                 fclose(f);
                 return r;
         }
@@ -708,7 +708,7 @@ int read_one_line_file(const char *fn, char **line) {
                 return -errno;
 
         if (!(fgets(t, sizeof(t), f))) {
-                r = -errno;
+                r = feof(f) ? -EIO : -errno;
                 goto finish;
         }
 
@@ -3266,7 +3266,7 @@ int get_ctty_devnr(pid_t pid, dev_t *d) {
                 return -errno;
 
         if (!fgets(line, sizeof(line), f)) {
-                k = -errno;
+                k = feof(f) ? -EIO : -errno;
                 fclose(f);
                 return k;
         }
@@ -5703,3 +5703,36 @@ int strdup_or_null(const char *a, char **b) {
         *b = c;
         return 0;
 }
+
+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;
+}