Merge remote-tracking branch 'remotes/stefanha/tags/tracing-pull-request' into staging

Pull request

# gpg: Signature made Wed 24 Jun 2020 11:25:27 BST
# gpg:                using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  trace/simple: Fix unauthorized enable
  scripts/tracetool: Update maintainer email address

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 14 insertions, 6 deletions

diff --git a/trace/simple.c b/trace/simple.c
index fc7106ec49..9cd2ed1fb3 100644
--- a/trace/simple.c
+++ b/trace/simple.c
@@ -302,10 +302,17 @@ static int st_write_event_mapping(void)
     return 0;
 }
 
-void st_set_trace_file_enabled(bool enable)
+/**
+ * Enable / disable tracing, return whether it was enabled.
+ *
+ * @enable: enable if %true, else disable.
+ */
+bool st_set_trace_file_enabled(bool enable)
 {
+    bool was_enabled = trace_fp;
+
     if (enable == !!trace_fp) {
-        return; /* no change */
+        return was_enabled;     /* no change */
     }
 
     /* Halt trace writeout */
@@ -323,14 +330,14 @@ void st_set_trace_file_enabled(bool enable)
 
         trace_fp = fopen(trace_file_name, "wb");
         if (!trace_fp) {
-            return;
+            return was_enabled;
         }
 
         if (fwrite(&header, sizeof header, 1, trace_fp) != 1 ||
             st_write_event_mapping() < 0) {
             fclose(trace_fp);
             trace_fp = NULL;
-            return;
+            return was_enabled;
         }
 
         /* Resume trace writeout */
@@ -340,6 +347,7 @@ void st_set_trace_file_enabled(bool enable)
         fclose(trace_fp);
         trace_fp = NULL;
     }
+    return was_enabled;
 }
 
 /**
@@ -350,7 +358,7 @@ void st_set_trace_file_enabled(bool enable)
  */
 void st_set_trace_file(const char *file)
 {
-    st_set_trace_file_enabled(false);
+    bool saved_enable = st_set_trace_file_enabled(false);
 
     g_free(trace_file_name);
 
@@ -361,7 +369,7 @@ void st_set_trace_file(const char *file)
         trace_file_name = g_strdup_printf("%s", file);
     }
 
-    st_set_trace_file_enabled(true);
+    st_set_trace_file_enabled(saved_enable);
 }
 
 void st_print_trace_file_status(void)