tools lib traceevent: Refactor process_filter()

So that it can return a proper pevent_errno value.

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/1386833777-3790-11-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

2 files changed, 42 insertions, 28 deletions

diff --git a/tools/lib/traceevent/event-parse.h b/tools/lib/traceevent/event-parse.h
index 57b66aed8122..da942d59cc3a 100644
--- a/tools/lib/traceevent/event-parse.h
+++ b/tools/lib/traceevent/event-parse.h
@@ -368,7 +368,11 @@ enum pevent_flag {
         _PE(REPARENT_NOT_OP,    "cannot reparent other than OP"),             \
         _PE(REPARENT_FAILED,    "failed to reparent filter OP"),              \
         _PE(BAD_FILTER_ARG,     "bad arg in filter tree"),                    \
-        _PE(UNEXPECTED_TYPE,    "unexpected type (not a value)")
+        _PE(UNEXPECTED_TYPE,    "unexpected type (not a value)"),             \
+        _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")
 
 #undef _PE
 #define _PE(__code, __str) PEVENT_ERRNO__ ## __code
diff --git a/tools/lib/traceevent/parse-filter.c b/tools/lib/traceevent/parse-filter.c
index 8d71208f0131..5aa5012a17ee 100644
--- a/tools/lib/traceevent/parse-filter.c
+++ b/tools/lib/traceevent/parse-filter.c
@@ -937,9 +937,10 @@ static int test_arg(struct filter_arg *parent, struct filter_arg *arg,
 }
 
 /* Remove any unknown event fields */
-static struct filter_arg *collapse_tree(struct filter_arg *arg, char **error_str)
+static int collapse_tree(struct filter_arg *arg,
+                         struct filter_arg **arg_collapsed, char **error_str)
 {
-        enum filter_vals ret;
+        int ret;
 
         ret = test_arg(arg, arg, error_str);
         switch (ret) {
@@ -955,6 +956,7 @@ static struct filter_arg *collapse_tree(struct filter_arg *arg, char **error_str
                         arg->boolean.value = ret == FILTER_VAL_TRUE;
                 } else {
                         show_error(error_str, "Failed to allocate filter arg");
+                        ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
                 }
                 break;
 
@@ -965,10 +967,11 @@ static struct filter_arg *collapse_tree(struct filter_arg *arg, char **error_str
                 break;
         }
 
-        return arg;
+        *arg_collapsed = arg;
+        return ret;
 }
 
-static int
+static enum pevent_errno
 process_filter(struct event_format *event, struct filter_arg **parg,
                char **error_str, int not)
 {
@@ -982,7 +985,7 @@ process_filter(struct event_format *event, struct filter_arg **parg,
         enum filter_op_type btype;
         enum filter_exp_type etype;
         enum filter_cmp_type ctype;
-        int ret;
+        enum pevent_errno ret;
 
         *parg = NULL;
 
@@ -1007,20 +1010,20 @@ process_filter(struct event_format *event, struct filter_arg **parg,
                                 if (not) {
                                         arg = NULL;
                                         if (current_op)
-                                                goto fail_print;
+                                                goto fail_syntax;
                                         free(token);
                                         *parg = current_exp;
                                         return 0;
                                 }
                         } else
-                                goto fail_print;
+                                goto fail_syntax;
                         arg = NULL;
                         break;
 
                 case EVENT_DELIM:
                         if (*token == ',') {
-                                show_error(error_str,
-                                           "Illegal token ','");
+                                show_error(error_str, "Illegal token ','");
+                                ret = PEVENT_ERRNO__ILLEGAL_TOKEN;
                                 goto fail;
                         }
 
@@ -1028,19 +1031,23 @@ process_filter(struct event_format *event, struct filter_arg **parg,
                                 if (left_item) {
                                         show_error(error_str,
                                                    "Open paren can not come after item");
+                                        ret = PEVENT_ERRNO__INVALID_PAREN;
                                         goto fail;
                                 }
                                 if (current_exp) {
                                         show_error(error_str,
                                                    "Open paren can not come after expression");
+                                        ret = PEVENT_ERRNO__INVALID_PAREN;
                                         goto fail;
                                 }
 
                                 ret = process_filter(event, &arg, error_str, 0);
-                                if (ret != 1) {
-                                        if (ret == 0)
+                                if (ret != PEVENT_ERRNO__UNBALANCED_PAREN) {
+                                        if (ret == 0) {
                                                 show_error(error_str,
                                                            "Unbalanced number of '('");
+                                                ret = PEVENT_ERRNO__UNBALANCED_PAREN;
+                                        }
                                         goto fail;
                                 }
                                 ret = 0;
@@ -1048,7 +1055,7 @@ process_filter(struct event_format *event, struct filter_arg **parg,
                                 /* A not wants just one expression */
                                 if (not) {
                                         if (current_op)
-                                                goto fail_print;
+                                                goto fail_syntax;
                                         *parg = arg;
                                         return 0;
                                 }
@@ -1063,19 +1070,19 @@ process_filter(struct event_format *event, struct filter_arg **parg,
 
                         } else { /* ')' */
                                 if (!current_op && !current_exp)
-                                        goto fail_print;
+                                        goto fail_syntax;
 
                                 /* Make sure everything is finished at this level */
                                 if (current_exp && !check_op_done(current_exp))
-                                        goto fail_print;
+                                        goto fail_syntax;
                                 if (current_op && !check_op_done(current_op))
-                                        goto fail_print;
+                                        goto fail_syntax;
 
                                 if (current_op)
                                         *parg = current_op;
                                 else
                                         *parg = current_exp;
-                                return 1;
+                                return PEVENT_ERRNO__UNBALANCED_PAREN;
                         }
                         break;
 
@@ -1087,21 +1094,22 @@ process_filter(struct event_format *event, struct filter_arg **parg,
                         case OP_BOOL:
                                 /* Logic ops need a left expression */
                                 if (!current_exp && !current_op)
-                                        goto fail_print;
+                                        goto fail_syntax;
                                 /* fall through */
                         case OP_NOT:
                                 /* logic only processes ops and exp */
                                 if (left_item)
-                                        goto fail_print;
+                                        goto fail_syntax;
                                 break;
                         case OP_EXP:
                         case OP_CMP:
                                 if (!left_item)
-                                        goto fail_print;
+                                        goto fail_syntax;
                                 break;
                         case OP_NONE:
                                 show_error(error_str,
                                            "Unknown op token %s", token);
+                                ret = PEVENT_ERRNO__UNKNOWN_TOKEN;
                                 goto fail;
                         }
 
@@ -1152,7 +1160,7 @@ process_filter(struct event_format *event, struct filter_arg **parg,
                                 ret = add_left(arg, left_item);
                                 if (ret < 0) {
                                         arg = NULL;
-                                        goto fail_print;
+                                        goto fail_syntax;
                                 }
                                 current_exp = arg;
                                 break;
@@ -1161,25 +1169,25 @@ process_filter(struct event_format *event, struct filter_arg **parg,
                         }
                         arg = NULL;
                         if (ret < 0)
-                                goto fail_print;
+                                goto fail_syntax;
                         break;
                 case EVENT_NONE:
                         break;
                 case EVENT_ERROR:
                         goto fail_alloc;
                 default:
-                        goto fail_print;
+                        goto fail_syntax;
                 }
         } while (type != EVENT_NONE);
 
         if (!current_op && !current_exp)
-                goto fail_print;
+                goto fail_syntax;
 
         if (!current_op)
                 current_op = current_exp;
 
-        current_op = collapse_tree(current_op, error_str);
-        if (current_op == NULL)
+        ret = collapse_tree(current_op, parg, error_str);
+        if (ret < 0)
                 goto fail;
 
         *parg = current_op;
@@ -1188,15 +1196,17 @@ process_filter(struct event_format *event, struct filter_arg **parg,
 
  fail_alloc:
         show_error(error_str, "failed to allocate filter arg");
+        ret = PEVENT_ERRNO__MEM_ALLOC_FAILED;
         goto fail;
- fail_print:
+ fail_syntax:
         show_error(error_str, "Syntax error");
+        ret = PEVENT_ERRNO__SYNTAX_ERROR;
  fail:
         free_arg(current_op);
         free_arg(current_exp);
         free_arg(arg);
         free(token);
-        return -1;
+        return ret;
 }
 
 static int