[PATCH v2 04/13] hw/mips/malta: Add re-usable rng_seed_hex_new() method

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

Extract common code from reinitialize_rng_seed() and
load_kernel() to rng_seed_hex_new().

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/mips/malta.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/hw/mips/malta.c b/hw/mips/malta.c
index af74008c82..9fc6a7d313 100644
--- a/hw/mips/malta.c
+++ b/hw/mips/malta.c
@@ -850,15 +850,24 @@ static void G_GNUC_PRINTF(3, 4) prom_set(uint32_t *prom_buf, int index,
     va_end(ap);
 }
 
-static void reinitialize_rng_seed(void *opaque)
+static char *rng_seed_hex_new(void)
 {
-    char *rng_seed_hex = opaque;
     uint8_t rng_seed[32];
+    char rng_seed_hex[sizeof(rng_seed) * 2 + 1];
 
     qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed));
     for (size_t i = 0; i < sizeof(rng_seed); ++i) {
         sprintf(rng_seed_hex + i * 2, "%02x", rng_seed[i]);
     }
+
+    return g_strdup(rng_seed_hex);
+}
+
+static void reinitialize_rng_seed(void *opaque)
+{
+    g_autofree char *rng_seed_hex = rng_seed_hex_new();
+
+    strcpy(opaque, rng_seed_hex);
 }
 
 /* Kernel */
@@ -870,8 +879,7 @@ static uint64_t load_kernel(void)
     uint32_t *prom_buf;
     long prom_size;
     int prom_index = 0;
-    uint8_t rng_seed[32];
-    char rng_seed_hex[sizeof(rng_seed) * 2 + 1];
+    g_autofree char *rng_seed_hex = rng_seed_hex_new();
     size_t rng_seed_prom_offset;
 
     kernel_size = load_elf(loaderparams.kernel_filename, NULL,
@@ -946,10 +954,6 @@ static uint64_t load_kernel(void)
     prom_set(prom_buf, prom_index++, "modetty0");
     prom_set(prom_buf, prom_index++, "38400n8r");
 
-    qemu_guest_getrandom_nofail(rng_seed, sizeof(rng_seed));
-    for (size_t i = 0; i < sizeof(rng_seed); ++i) {
-        sprintf(rng_seed_hex + i * 2, "%02x", rng_seed[i]);
-    }
     prom_set(prom_buf, prom_index++, "rngseed");
     rng_seed_prom_offset = prom_index * ENVP_ENTRY_SIZE +
                            sizeof(uint32_t) * ENVP_NB_ENTRIES;
-- 
2.41.0