[PATCH v9 19/52] dyndbg: treat comma as a token separator

Jim Cromie
2024-07-02T21:58:38Z

Treat comma as a token terminator, just like a space. This allows a
user to avoid quoting hassles when spaces are otherwise needed:

:#> modprobe drm dyndbg=class,DRM_UT_CORE,+p\;class,DRM_UT_KMS,+p

or as a boot arg:

drm.dyndbg=class,DRM_UT_CORE,+p # todo: support multi-query here

Given the many ways a boot-line +args can be assembled and then passed
in/down/around shell based tools, this may allow side-stepping all
sorts of quoting hassles thru those layers.

existing query format:

modprobe test_dynamic_debug dyndbg="class D2_CORE +p"

new format:

modprobe test_dynamic_debug dyndbg=class,D2_CORE,+p

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Co-developed-by: Łukasz Bartosik <ukaszb@chromium.org>
Signed-off-by: Łukasz Bartosik <ukaszb@chromium.org>
---
lib/dynamic_debug.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index e9a95b0f3757..235d85765b63 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -290,6 +290,14 @@ static int ddebug_change(const struct ddebug_query *query,
return nfound;
}

+static char *skip_spaces_and_commas(const char *str)
+{
+ str = skip_spaces(str);
+ while (*str == ',')
+ str = skip_spaces(++str);
+ return (char *)str;
+}
+
/*
* Split the buffer `buf' into space-separated words.
* Handles simple " and ' quoting, i.e. without nested,
@@ -303,8 +311,8 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
while (*buf) {
char *end;

- /* Skip leading whitespace */
- buf = skip_spaces(buf);
+ /* Skip leading whitespace and comma */
+ buf = skip_spaces_and_commas(buf);
if (!*buf)
break; /* oh, it was trailing whitespace */
if (*buf == '#')
@@ -320,7 +328,7 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
return -EINVAL; /* unclosed quote */
}
} else {
- for (end = buf; *end && !isspace(*end); end++)
+ for (end = buf; *end && !isspace(*end) && *end != ','; end++)
;
if (end == buf) {
pr_err("parse err after word:%d=%s\n", nwords,
@@ -592,7 +600,8 @@ static int ddebug_exec_queries(char *query, const char *modname)
if (split)
*split++ = '\0';

- query = skip_spaces(query);
+ query = skip_spaces_and_commas(query);
+
if (!query || !*query || *query == '#')
continue;

--
2.45.2