util.c: add in_initrd()

in_initrd() checks, if the stat() for the device for "/" is 1, which it
is for the initramfs.

2 files changed, 16 insertions, 0 deletions

diff --git a/src/shared/util.c b/src/shared/util.c
index 53185403d6..681484bc0f 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -5639,3 +5639,18 @@ bool is_valid_documentation_url(const char *url) {
 
         return false;
 }
+
+bool in_initrd(void) {
+        static bool checked=false;
+        static bool is_in_initrd=false;
+
+        if (!checked) {
+                struct stat sb;
+                if (stat("/", &sb) == 0) {
+                        is_in_initrd = (sb.st_dev == 1);
+                        checked = true;
+                }
+        }
+
+        return is_in_initrd;
+}
diff --git a/src/shared/util.h b/src/shared/util.h
index 0af0299dbb..4fccf96a6d 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -512,4 +512,5 @@ int can_sleep(const char *type);
 
 bool is_valid_documentation_url(const char *url);
 
+bool in_initrd(void);
 #endif