perf tools: Fix backslash processing on trace print formats

The handling of backslashes was broken. It would stop parsing
when encountering one. Also, '\n', '\t', '\r' and '\\' were not
converted.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <20091014194357.521974680@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 25 insertions, 2 deletions

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index a05c7144aded..2b75ec2f57e8 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -522,7 +522,10 @@ static enum event_type __read_token(char **tok)
                         last_ch = ch;
                         ch = __read_char();
                         buf[i++] = ch;
-                } while (ch != quote_ch && last_ch != '\\');
+                        /* the '\' '\' will cancel itself */
+                        if (ch == '\\' && last_ch == '\\')
+                                last_ch = 0;
+                } while (ch != quote_ch || last_ch == '\\');
                 /* remove the last quote */
                 i--;
                 goto out;
@@ -2325,7 +2328,27 @@ static void pretty_print(void *data, int size, struct event *event)
 
         for (; *ptr; ptr++) {
                 ls = 0;
-                if (*ptr == '%') {
+                if (*ptr == '\\') {
+                        ptr++;
+                        switch (*ptr) {
+                        case 'n':
+                                printf("\n");
+                                break;
+                        case 't':
+                                printf("\t");
+                                break;
+                        case 'r':
+                                printf("\r");
+                                break;
+                        case '\\':
+                                printf("\\");
+                                break;
+                        default:
+                                printf("%c", *ptr);
+                                break;
+                        }
+
+                } else if (*ptr == '%') {
                         saveptr = ptr;
                         show_func = 0;
  cont_process: