1 files changed, 33 insertions, 0 deletions
diff --git a/builder/modules.d/dnbd3-rootfs/binaries/systemd-preserve-process-marker/systemd-preserve-process-marker.c b/builder/modules.d/dnbd3-rootfs/binaries/systemd-preserve-process-marker/systemd-preserve-process-marker.c
new file mode 100644
index 00000000..8f0fc108
--- /dev/null
+++ b/builder/modules.d/dnbd3-rootfs/binaries/systemd-preserve-process-marker/systemd-preserve-process-marker.c
@@ -0,0 +1,33 @@
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+void print_array(int argc, char *argv[]) {
+    // Helper function to print given array with given length.
+    int i = 0;
+    int j = 0;
+    for (i = 0; i < argc; i ++) {
+        j = 0;
+        while(argv[i][j] != '\0')
+            printf("%c", argv[i][j++]);
+        printf(" ");
+    }
+    printf("\n");
+}
+int main(int argc, char *argv[]) {
+    int count;
+    // Last item acts as null pointer.
+    char **copy = calloc(sizeof(char *), argc);
+    // Slice first given command line argument.
+    for (count = 0; count < argc - 1; count++)
+        copy[count] = strdup(argv[count + 1]);
+    // Adding systemd indicator to preserve wrapped process during changing
+    // root filesystem. We mark wrapper and child process.
+    argv[0][0] = '@';
+    copy[0][0] = '@';
+    if (-1 == execvp(argv[1], copy)) {
+        perror("Executing child process failed.");
+        return -1;
+    }
+}