3 files changed, 42 insertions, 0 deletions

diff --git a/src/shared/serialize.c b/src/shared/serialize.c
index 2ffc524f15..dc282e398e 100644
--- a/src/shared/serialize.c
+++ b/src/shared/serialize.c
@@ -7,6 +7,7 @@
 #include "escape.h"
 #include "fd-util.h"
 #include "fileio.h"
+#include "hexdecoct.h"
 #include "memfd-util.h"
 #include "missing_mman.h"
 #include "missing_syscall.h"
@@ -173,6 +174,28 @@ int serialize_pidref(FILE *f, FDSet *fds, const char *key, PidRef *pidref) {
         return serialize_item_format(f, key, "@%i", copy);
 }
 
+int serialize_item_hexmem(FILE *f, const char *key, const void *p, size_t l) {
+        _cleanup_free_ char *encoded = NULL;
+        int r;
+
+        assert(f);
+        assert(key);
+        assert(p || l == 0);
+
+        if (l == 0)
+                return 0;
+
+        encoded = hexmem(p, l);
+        if (!encoded)
+                return log_oom_debug();
+
+        r = serialize_item(f, key, encoded);
+        if (r < 0)
+                return r;
+
+        return 1;
+}
+
 int deserialize_read_line(FILE *f, char **ret) {
         _cleanup_free_ char *line = NULL;
         int r;
diff --git a/src/shared/serialize.h b/src/shared/serialize.h
index 9463d1127c..17bc968c04 100644
--- a/src/shared/serialize.h
+++ b/src/shared/serialize.h
@@ -12,6 +12,7 @@
 int serialize_item(FILE *f, const char *key, const char *value);
 int serialize_item_escaped(FILE *f, const char *key, const char *value);
 int serialize_item_format(FILE *f, const char *key, const char *value, ...) _printf_(3,4);
+int serialize_item_hexmem(FILE *f, const char *key, const void *p, size_t l);
 int serialize_fd(FILE *f, FDSet *fds, const char *key, int fd);
 int serialize_usec(FILE *f, const char *key, usec_t usec);
 int serialize_dual_timestamp(FILE *f, const char *key, const dual_timestamp *t);
diff --git a/src/test/test-serialize.c b/src/test/test-serialize.c
index 36052b6485..501f5c6f2e 100644
--- a/src/test/test-serialize.c
+++ b/src/test/test-serialize.c
@@ -190,6 +190,24 @@ TEST(serialize_environment) {
         assert_se(strv_equal(env, env2));
 }
 
+TEST(serialize_item_hexmem) {
+        _cleanup_(unlink_tempfilep) char fn[] = "/tmp/test-serialize.XXXXXX";
+        _cleanup_fclose_ FILE *f = NULL;
+
+        assert_se(fmkostemp_safe(fn, "r+", &f) == 0);
+        log_info("/* %s (%s) */", __func__, fn);
+
+        assert_se(serialize_item_hexmem(f, "a", NULL, 0) == 0);
+        assert_se(serialize_item_hexmem(f, "a", (uint8_t []){0xff, 0xff, 0xff}, sizeof(uint8_t) * 3) == 1);
+
+        rewind(f);
+
+        _cleanup_free_ char *line = NULL;
+        assert_se(read_line(f, LONG_LINE_MAX, &line) > 0);
+        assert_se(streq(line, "a=ffffff"));
+
+}
+
 static int intro(void) {
         memset(long_string, 'x', sizeof(long_string)-1);
         char_array_0(long_string);