backends/tpm: Use qemu_hexdump_line() to avoid sprintf()

sprintf() is deprecated on Darwin since macOS 13.0 / XCode 14.1.
Using qemu_hexdump_line() both fixes the deprecation warning and
simplifies the code base.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
[rth: Keep the linebreaks every 16 bytes]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20240412073346.458116-12-richard.henderson@linaro.org>
[PMD: Rebased]

1 files changed, 10 insertions, 14 deletions

diff --git a/backends/tpm/tpm_util.c b/backends/tpm/tpm_util.c
index 3294625..0a428ea 100644
--- a/backends/tpm/tpm_util.c
+++ b/backends/tpm/tpm_util.c
@@ -21,6 +21,7 @@
 
 #include "qemu/osdep.h"
 #include "qemu/error-report.h"
+#include "qemu/cutils.h"
 #include "qapi/error.h"
 #include "qapi/visitor.h"
 #include "tpm_int.h"
@@ -336,8 +337,8 @@ void tpm_sized_buffer_reset(TPMSizedBuffer *tsb)
 void tpm_util_show_buffer(const unsigned char *buffer,
                           size_t buffer_size, const char *string)
 {
-    size_t len, i;
-    char *line_buffer, *p;
+    g_autoptr(GString) str = NULL;
+    size_t len, i, l;
 
     if (!trace_event_get_state_backends(TRACE_TPM_UTIL_SHOW_BUFFER_CONTENT)) {
         return;
@@ -345,19 +346,14 @@ void tpm_util_show_buffer(const unsigned char *buffer,
     len = MIN(tpm_cmd_get_size(buffer), buffer_size);
     trace_tpm_util_show_buffer_header(string, len);
 
-    /*
-     * allocate enough room for 3 chars per buffer entry plus a
-     * newline after every 16 chars and a final null terminator.
-     */
-    line_buffer = g_malloc(len * 3 + (len / 16) + 1);
-
-    for (i = 0, p = line_buffer; i < len; i++) {
-        if (i && !(i % 16)) {
-            p += sprintf(p, "\n");
+    for (i = 0; i < len; i += l) {
+        if (str) {
+            g_string_append_c(str, '\n');
         }
-        p += sprintf(p, "%.2X ", buffer[i]);
+        l = MIN(len, 16);
+        str = qemu_hexdump_line(str, buffer, l, 1, 0);
     }
-    trace_tpm_util_show_buffer_content(line_buffer);
 
-    g_free(line_buffer);
+    g_string_ascii_up(str);
+    trace_tpm_util_show_buffer_content(str->str);
 }