[PULL 04/46] fuzz: log the arguments used to initialize QEMU

[Paolo Bonzini]

From: Alexander Bulekov <alxndr@bu.edu>

This is useful for building reproducers. Instead checking the code or
the QEMU_FUZZ_ARGS, the arguments are at the top of the crash log.

Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210117201014.271610-3-alxndr@bu.edu>
---
 tests/qtest/fuzz/fuzz.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/tests/qtest/fuzz/fuzz.c b/tests/qtest/fuzz/fuzz.c
index 238866a037..496d11a231 100644
--- a/tests/qtest/fuzz/fuzz.c
+++ b/tests/qtest/fuzz/fuzz.c
@@ -159,6 +159,8 @@ int LLVMFuzzerInitialize(int *argc, char ***argv, char 
***envp)
     char *target_name;
     const char *bindir;
     char *datadir;
+    GString *cmd_line;
+    gchar *pretty_cmd_line;
     bool serialize = false;
 
     /* Initialize qgraph and modules */
@@ -217,7 +219,7 @@ int LLVMFuzzerInitialize(int *argc, char ***argv, char 
***envp)
     }
 
     /* Run QEMU's softmmu main with the fuzz-target dependent arguments */
-    GString *cmd_line = fuzz_target->get_init_cmdline(fuzz_target);
+    cmd_line = fuzz_target->get_init_cmdline(fuzz_target);
     g_string_append_printf(cmd_line, " %s -qtest /dev/null ",
                            getenv("QTEST_LOG") ? "" : "-qtest-log none");
 
@@ -226,6 +228,13 @@ int LLVMFuzzerInitialize(int *argc, char ***argv, char 
***envp)
     wordexp(cmd_line->str, &result, 0);
     g_string_free(cmd_line, true);
 
+    if (getenv("QTEST_LOG")) {
+        pretty_cmd_line  = g_strjoinv(" ", result.we_wordv + 1);
+        printf("Starting %s with Arguments: %s\n",
+                result.we_wordv[0], pretty_cmd_line);
+        g_free(pretty_cmd_line);
+    }
+
     qemu_init(result.we_wordc, result.we_wordv, NULL);
 
     /* re-enable the rcu atfork, which was previously disabled in qemu_init */
-- 
2.29.2