1 files changed, 81 insertions, 23 deletions

diff --git a/tools/lib/traceevent/event-parse.c b/tools/lib/traceevent/event-parse.c
index b7c2c491f61e..b5b4d806ffa2 100644
--- a/tools/lib/traceevent/event-parse.c
+++ b/tools/lib/traceevent/event-parse.c
@@ -4686,9 +4686,8 @@ static int find_event_handle(struct pevent *pevent, struct event_format *event)
  *
  * /sys/kernel/debug/tracing/events/.../.../format
  */
-int pevent_parse_event(struct pevent *pevent,
-                       const char *buf, unsigned long size,
-                       const char *sys)
+enum pevent_errno pevent_parse_event(struct pevent *pevent, const char *buf,
+                                     unsigned long size, const char *sys)
 {
         struct event_format *event;
         int ret;
@@ -4697,17 +4696,16 @@ int pevent_parse_event(struct pevent *pevent,
 
         event = alloc_event();
         if (!event)
-                return -ENOMEM;
+                return PEVENT_ERRNO__MEM_ALLOC_FAILED;
 
         event->name = event_read_name();
         if (!event->name) {
                 /* Bad event? */
-                free(event);
-                return -1;
+                ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
+                goto event_alloc_failed;
         }
 
         if (strcmp(sys, "ftrace") == 0) {
-
                 event->flags |= EVENT_FL_ISFTRACE;
 
                 if (strcmp(event->name, "bprint") == 0)
@@ -4715,20 +4713,28 @@ int pevent_parse_event(struct pevent *pevent,
         }
                 
         event->id = event_read_id();
-        if (event->id < 0)
-                die("failed to read event id");
+        if (event->id < 0) {
+                ret = PEVENT_ERRNO__READ_ID_FAILED;
+                /*
+                 * This isn't an allocation error actually.
+                 * But as the ID is critical, just bail out.
+                 */
+                goto event_alloc_failed;
+        }
 
         event->system = strdup(sys);
-        if (!event->system)
-                die("failed to allocate system");
+        if (!event->system) {
+                ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
+                goto event_alloc_failed;
+        }
 
         /* Add pevent to event so that it can be referenced */
         event->pevent = pevent;
 
         ret = event_read_format(event);
         if (ret < 0) {
-                do_warning("failed to read event format for %s", event->name);
-                goto event_failed;
+                ret = PEVENT_ERRNO__READ_FORMAT_FAILED;
+                goto event_parse_failed;
         }
 
         /*
@@ -4740,10 +4746,9 @@ int pevent_parse_event(struct pevent *pevent,
 
         ret = event_read_print(event);
         if (ret < 0) {
-                do_warning("failed to read event print fmt for %s",
-                           event->name);
                 show_warning = 1;
-                goto event_failed;
+                ret = PEVENT_ERRNO__READ_PRINT_FAILED;
+                goto event_parse_failed;
         }
         show_warning = 1;
 
@@ -4754,20 +4759,19 @@ int pevent_parse_event(struct pevent *pevent,
                 struct print_arg *arg, **list;
 
                 /* old ftrace had no args */
-
                 list = &event->print_fmt.args;
                 for (field = event->format.fields; field; field = field->next) {
                         arg = alloc_arg();
-                        *list = arg;
-                        list = &arg->next;
                         arg->type = PRINT_FIELD;
                         arg->field.name = strdup(field->name);
                         if (!arg->field.name) {
-                                do_warning("failed to allocate field name");
                                 event->flags |= EVENT_FL_FAILED;
-                                return -1;
+                                free_arg(arg);
+                                return PEVENT_ERRNO__OLD_FTRACE_ARG_FAILED;
                         }
                         arg->field.field = field;
+                        *list = arg;
+                        list = &arg->next;
                 }
                 return 0;
         }
@@ -4778,11 +4782,65 @@ int pevent_parse_event(struct pevent *pevent,
 
         return 0;
 
- event_failed:
+ event_parse_failed:
         event->flags |= EVENT_FL_FAILED;
         /* still add it even if it failed */
         add_event(pevent, event);
-        return -1;
+        return ret;
+
+ event_alloc_failed:
+        free(event->system);
+        free(event->name);
+        free(event);
+        return ret;
+}
+
+#undef _PE
+#define _PE(code, str) str
+static const char * const pevent_error_str[] = {
+        PEVENT_ERRORS
+};
+#undef _PE
+
+int pevent_strerror(struct pevent *pevent, enum pevent_errno errnum,
+                    char *buf, size_t buflen)
+{
+        int idx;
+        const char *msg;
+
+        if (errnum >= 0) {
+                msg = strerror_r(errnum, buf, buflen);
+                if (msg != buf) {
+                        size_t len = strlen(msg);
+                        char *c = mempcpy(buf, msg, min(buflen-1, len));
+                        *c = '\0';
+                }
+                return 0;
+        }
+
+        if (errnum <= __PEVENT_ERRNO__START ||
+            errnum >= __PEVENT_ERRNO__END)
+                return -1;
+
+        idx = errnum - __PEVENT_ERRNO__START - 1;
+        msg = pevent_error_str[idx];
+
+        switch (errnum) {
+        case PEVENT_ERRNO__MEM_ALLOC_FAILED:
+        case PEVENT_ERRNO__PARSE_EVENT_FAILED:
+        case PEVENT_ERRNO__READ_ID_FAILED:
+        case PEVENT_ERRNO__READ_FORMAT_FAILED:
+        case PEVENT_ERRNO__READ_PRINT_FAILED:
+        case PEVENT_ERRNO__OLD_FTRACE_ARG_FAILED:
+                snprintf(buf, buflen, "%s", msg);
+                break;
+
+        default:
+                /* cannot reach here */
+                break;
+        }
+
+        return 0;
 }
 
 int get_field_val(struct trace_seq *s, struct format_field *field,