tools lib traceevent: Make pevent_filter_add_filter_str() return pevent_errno

Refactor the pevent_filter_add_filter_str() to return a proper error
code and get rid of the third error_str argument.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1386833777-3790-12-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 27 insertions, 59 deletions

diff --git a/tools/lib/traceevent/event-parse.h b/tools/lib/traceevent/event-parse.h
index da942d59cc3a..089964e56ed4 100644
--- a/tools/lib/traceevent/event-parse.h
+++ b/tools/lib/traceevent/event-parse.h
@@ -372,7 +372,8 @@ enum pevent_flag {
         _PE(ILLEGAL_TOKEN,      "illegal token"),                             \
         _PE(INVALID_PAREN,      "open parenthesis cannot come here"),         \
         _PE(UNBALANCED_PAREN,   "unbalanced number of parenthesis"),          \
-        _PE(UNKNOWN_TOKEN,      "unknown token")
+        _PE(UNKNOWN_TOKEN,      "unknown token"),                             \
+        _PE(FILTER_NOT_FOUND,   "no filter found")
 
 #undef _PE
 #define _PE(__code, __str) PEVENT_ERRNO__ ## __code
@@ -863,9 +864,8 @@ enum filter_trivial_type {
         FILTER_TRIVIAL_BOTH,
 };
 
-int pevent_filter_add_filter_str(struct event_filter *filter,
-                                 const char *filter_str,
-                                 char **error_str);
+enum pevent_errno pevent_filter_add_filter_str(struct event_filter *filter,
+                                               const char *filter_str);
 
 
 int pevent_filter_match(struct event_filter *filter,
diff --git a/tools/lib/traceevent/parse-filter.c b/tools/lib/traceevent/parse-filter.c
index 5aa5012a17ee..78440d73e0ad 100644
--- a/tools/lib/traceevent/parse-filter.c
+++ b/tools/lib/traceevent/parse-filter.c
@@ -1209,7 +1209,7 @@ process_filter(struct event_format *event, struct filter_arg **parg,
         return ret;
 }
 
-static int
+static enum pevent_errno
 process_event(struct event_format *event, const char *filter_str,
               struct filter_arg **parg, char **error_str)
 {
@@ -1218,21 +1218,15 @@ process_event(struct event_format *event, const char *filter_str,
         pevent_buffer_init(filter_str, strlen(filter_str));
 
         ret = process_filter(event, parg, error_str, 0);
-        if (ret == 1) {
-                show_error(error_str,
-                           "Unbalanced number of ')'");
-                return -1;
-        }
         if (ret < 0)
                 return ret;
 
         /* If parg is NULL, then make it into FALSE */
         if (!*parg) {
                 *parg = allocate_arg();
-                if (*parg == NULL) {
-                        show_error(error_str, "failed to allocate filter arg");
-                        return -1;
-                }
+                if (*parg == NULL)
+                        return PEVENT_ERRNO__MEM_ALLOC_FAILED;
+
                 (*parg)->type = FILTER_ARG_BOOLEAN;
                 (*parg)->boolean.value = FILTER_FALSE;
         }
@@ -1240,13 +1234,13 @@ process_event(struct event_format *event, const char *filter_str,
         return 0;
 }
 
-static int filter_event(struct event_filter *filter,
-                        struct event_format *event,
-                        const char *filter_str, char **error_str)
+static enum pevent_errno
+filter_event(struct event_filter *filter, struct event_format *event,
+             const char *filter_str, char **error_str)
 {
         struct filter_type *filter_type;
         struct filter_arg *arg;
-        int ret;
+        enum pevent_errno ret;
 
         if (filter_str) {
                 ret = process_event(event, filter_str, &arg, error_str);
@@ -1256,20 +1250,16 @@ static int filter_event(struct event_filter *filter,
         } else {
                 /* just add a TRUE arg */
                 arg = allocate_arg();
-                if (arg == NULL) {
-                        show_error(error_str, "failed to allocate filter arg");
-                        return -1;
-                }
+                if (arg == NULL)
+                        return PEVENT_ERRNO__MEM_ALLOC_FAILED;
+
                 arg->type = FILTER_ARG_BOOLEAN;
                 arg->boolean.value = FILTER_TRUE;
         }
 
         filter_type = add_filter_type(filter, event->id);
-        if (filter_type == NULL) {
-                show_error(error_str, "failed to add a new filter: %s",
-                           filter_str ? filter_str : "true");
-                return -1;
-        }
+        if (filter_type == NULL)
+                return PEVENT_ERRNO__MEM_ALLOC_FAILED;
 
         if (filter_type->filter)
                 free_arg(filter_type->filter);
@@ -1282,18 +1272,12 @@ static int filter_event(struct event_filter *filter,
  * pevent_filter_add_filter_str - add a new filter
  * @filter: the event filter to add to
  * @filter_str: the filter string that contains the filter
- * @error_str: string containing reason for failed filter
- *
- * Returns 0 if the filter was successfully added
- *   -1 if there was an error.
  *
- * On error, if @error_str points to a string pointer,
- * it is set to the reason that the filter failed.
- * This string must be freed with "free".
+ * Returns 0 if the filter was successfully added or a
+ * negative error code.
  */
-int pevent_filter_add_filter_str(struct event_filter *filter,
-                                 const char *filter_str,
-                                 char **error_str)
+enum pevent_errno pevent_filter_add_filter_str(struct event_filter *filter,
+                                               const char *filter_str)
 {
         struct pevent *pevent = filter->pevent;
         struct event_list *event;
@@ -1304,23 +1288,20 @@ int pevent_filter_add_filter_str(struct event_filter *filter,
         char *event_name = NULL;
         char *sys_name = NULL;
         char *sp;
-        int rtn = 0;
+        enum pevent_errno rtn = 0; /* PEVENT_ERRNO__SUCCESS */
         int len;
         int ret;
+        char *error_str = NULL;
 
         /* clear buffer to reset show error */
         pevent_buffer_init("", 0);
 
-        if (error_str)
-                *error_str = NULL;
-
         filter_start = strchr(filter_str, ':');
         if (filter_start)
                 len = filter_start - filter_str;
         else
                 len = strlen(filter_str);
 
-
         do {
                 next_event = strchr(filter_str, ',');
                 if (next_event &&
@@ -1333,10 +1314,9 @@ int pevent_filter_add_filter_str(struct event_filter *filter,
 
                 this_event = malloc(len + 1);
                 if (this_event == NULL) {
-                        show_error(error_str, "Memory allocation failure");
                         /* This can only happen when events is NULL, but still */
                         free_events(events);
-                        return -1;
+                        return PEVENT_ERRNO__MEM_ALLOC_FAILED;
                 }
                 memcpy(this_event, filter_str, len);
                 this_event[len] = 0;
@@ -1350,30 +1330,18 @@ int pevent_filter_add_filter_str(struct event_filter *filter,
                 event_name = strtok_r(NULL, "/", &sp);
 
                 if (!sys_name) {
-                        show_error(error_str, "No filter found");
                         /* This can only happen when events is NULL, but still */
                         free_events(events);
                         free(this_event);
-                        return -1;
+                        return PEVENT_ERRNO__FILTER_NOT_FOUND;
                 }
 
                 /* Find this event */
                 ret = find_event(pevent, &events, strim(sys_name), strim(event_name));
                 if (ret < 0) {
-                        if (ret == PEVENT_ERRNO__MEM_ALLOC_FAILED)
-                                show_error(error_str,
-                                           "Memory allocation failure");
-                        else if (event_name)
-                                show_error(error_str,
-                                           "No event found under '%s.%s'",
-                                           sys_name, event_name);
-                        else
-                                show_error(error_str,
-                                           "No event found under '%s'",
-                                           sys_name);
                         free_events(events);
                         free(this_event);
-                        return -1;
+                        return ret;
                 }
                 free(this_event);
         } while (filter_str);
@@ -1385,7 +1353,7 @@ int pevent_filter_add_filter_str(struct event_filter *filter,
         /* filter starts here */
         for (event = events; event; event = event->next) {
                 ret = filter_event(filter, event->event, filter_start,
-                                   error_str);
+                                   &error_str);
                 /* Failures are returned if a parse error happened */
                 if (ret < 0)
                         rtn = ret;