parse-events: Add support for "%.*s" in bprintk events

The arg notation of '*' in bprintks is not handled by the parser.
Implement it so that they show up properly in the output and do not
kill the tracer from reporting events.

Reported-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 25 insertions, 9 deletions

diff --git a/parse-events.c b/parse-events.c
index ca9fbb0..da1d0a6 100644
--- a/parse-events.c
+++ b/parse-events.c
@@ -3270,7 +3270,7 @@ static void print_str_arg(struct trace_seq *s, void *data, int size,
                 break;
         }
         case PRINT_BSTRING:
-                trace_seq_printf(s, format, arg->string.string);
+                print_str_to_seq(s, format, len_arg, arg->string.string);
                 break;
         case PRINT_OP:
                 /*
@@ -3370,6 +3370,7 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
         unsigned long long ip, val;
         char *ptr;
         void *bptr;
+        int vsize;
 
         field = pevent->bprint_buf_field;
         ip_field = pevent->bprint_ip_field;
@@ -3418,6 +3419,8 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
                                 goto process_again;
                         case '0' ... '9':
                                 goto process_again;
+                        case '.':
+                                goto process_again;
                         case 'p':
                                 ls = 1;
                                 /* fall through */
@@ -3425,23 +3428,29 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
                         case 'u':
                         case 'x':
                         case 'i':
-                                /* the pointers are always 4 bytes aligned */
-                                bptr = (void *)(((unsigned long)bptr + 3) &
-                                                ~3);
                                 switch (ls) {
                                 case 0:
-                                        ls = 4;
+                                        vsize = 4;
                                         break;
                                 case 1:
-                                        ls = pevent->long_size;
+                                        vsize = pevent->long_size;
                                         break;
                                 case 2:
-                                        ls = 8;
+                                        vsize = 8;
                                 default:
+                                        vsize = ls; /* ? */
                                         break;
                                 }
-                                val = pevent_read_number(pevent, bptr, ls);
-                                bptr += ls;
+                        /* fall through */
+                        case '*':
+                                if (*ptr == '*')
+                                        vsize = 4;
+
+                                /* the pointers are always 4 bytes aligned */
+                                bptr = (void *)(((unsigned long)bptr + 3) &
+                                                ~3);
+                                val = pevent_read_number(pevent, bptr, vsize);
+                                bptr += vsize;
                                 arg = alloc_arg();
                                 arg->next = NULL;
                                 arg->type = PRINT_ATOM;
@@ -3449,6 +3458,13 @@ static struct print_arg *make_bprint_args(char *fmt, void *data, int size, struc
                                 sprintf(arg->atom.atom, "%lld", val);
                                 *next = arg;
                                 next = &arg->next;
+                                /*
+                                 * The '*' case means that an arg is used as the length.
+                                 * We need to continue to figure out for what.
+                                 */
+                                if (*ptr == '*')
+                                        goto process_again;
+
                                 break;
                         case 's':
                                 arg = alloc_arg();