trace-cmd: Allow plugin handlers to let the default print to also happen

A plugin may only need to translate part of the field, or if it fails to
translate, it may want the default to print.

Now if a plugin handler returns something other than 0, the default print
handler will take place.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

2 files changed, 20 insertions, 15 deletions

diff --git a/parse-events.c b/parse-events.c
index 53aad3e..d2d7e0a 100644
--- a/parse-events.c
+++ b/parse-events.c
@@ -3324,9 +3324,12 @@ const char *pevent_data_comm_from_pid(struct pevent *pevent, int pid)
 void pevent_event_info(struct trace_seq *s, struct event_format *event,
                        struct record *record)
 {
+        int print_pretty = 1;
+
         if (event->handler)
-                event->handler(s, record, event);
-        else
+                print_pretty = event->handler(s, record, event);
+
+        if (print_pretty)
                 pretty_print(s, record->data, record->size, event);
 
         trace_seq_terminate(s);
@@ -3342,6 +3345,7 @@ void pevent_print_event(struct pevent *pevent, struct trace_seq *s,
         const char *comm;
         void *data = record->data;
         int size = record->size;
+        int print_pretty = 1;
         int type;
         int pid;
         int len;
@@ -3376,8 +3380,9 @@ void pevent_print_event(struct pevent *pevent, struct trace_seq *s,
                 trace_seq_printf(s, "%.*s", 20 - len, spaces);
         
         if (event->handler)
-                event->handler(s, record, event);
-        else
+                print_pretty = event->handler(s, record, event);
+
+        if (print_pretty)
                 pretty_print(s, data, size, event);
 
         trace_seq_terminate(s);
diff --git a/trace-ftrace.c b/trace-ftrace.c
index 1b79ec7..8b0646b 100644
--- a/trace-ftrace.c
+++ b/trace-ftrace.c
@@ -229,7 +229,6 @@ fgraph_ent_handler(struct trace_seq *s, struct record *record,
         void *data = record->data;
         int size = record->size;
         int cpu = record->cpu;
-        int ret;
 
         if (get_field_val(s, data, event, "common_pid", &pid))
                 return trace_seq_putc(s, '!');
@@ -257,15 +256,15 @@ fgraph_ent_handler(struct trace_seq *s, struct record *record,
                  * We also do a new peek on this CPU to update the
                  * record cache.
                  */
-                ret = print_graph_entry_leaf(s, event, data, rec);
+                print_graph_entry_leaf(s, event, data, rec);
                 free_record(rec);
                 tracecmd_peek_data(tracecmd_curr_thread_handle, cpu);
         } else
-                ret = print_graph_nested(s, event, data);
+                print_graph_nested(s, event, data);
 
         free(data);
 
-        return ret;
+        return 0;
 }
 
 static int
@@ -298,7 +297,9 @@ fgraph_ret_handler(struct trace_seq *s, struct record *record,
         for (i = 0; i < (int)(depth * TRACE_GRAPH_INDENT); i++)
                 trace_seq_putc(s, ' ');
 
-        return trace_seq_putc(s, '}');
+        trace_seq_putc(s, '}');
+
+        return 0;
 }
 
 static int
@@ -309,16 +310,15 @@ trace_stack_handler(struct trace_seq *s, struct record *record,
         unsigned long long addr;
         const char *func;
         void *data = record->data;
-        int ret;
         int i;
 
         field = pevent_find_any_field(event, "caller");
         if (!field) {
                 trace_seq_printf(s, "<CANT FIND FIELD %s>", "caller");
-                return -1;
+                return 0;
         }
 
-        ret = trace_seq_puts(s, "<stack trace>\n");
+        trace_seq_puts(s, "<stack trace>\n");
 
         for (i = 0; i < field->size; i += long_size) {
                 addr = pevent_read_number(event->pevent,
@@ -330,12 +330,12 @@ trace_stack_handler(struct trace_seq *s, struct record *record,
 
                 func = pevent_find_function(event->pevent, addr);
                 if (func)
-                        ret = trace_seq_printf(s, "=> %s (%llx)\n", func, addr);
+                        trace_seq_printf(s, "=> %s (%llx)\n", func, addr);
                 else
-                        ret = trace_seq_printf(s, "=> %llx\n", addr);
+                        trace_seq_printf(s, "=> %llx\n", addr);
         }
 
-        return ret;
+        return 0;
 }
 
 int tracecmd_ftrace_overrides(struct tracecmd_input *handle)