Multi-query strings have long allowed:
modprobe drm dyndbg="class DRM_UT_CORE +p; class DRM_UT_KMS +p"
modprobe drm dyndbg=<<EOX
class DRM_UT_CORE +p
class DRM_UT_KMS +p
EOX
More recently, the need for quoting was avoided by treating a comma
like a space/token-terminator:
modprobe drm dyndbg=class,DRM_UT_CORE,+p\;class,DRM_UT_KMS,+p
That worked, but it left unfinished business; the semicolon in the
example above is a shell special-char (one of the bash control
operators), so it is brittle when passed in/down/around scripts. In
particular, it fails when passed to vng (virtme-ng).
So this patch adds '%' to the existing ';' and '\n' multi-cmd
separators, which is more shell-friendly, and also avoids quoting and
escaping hassles.
NOTE: it does break format matching on '%' patterns:
bash-5.2# ddcmd 'format "find-me: %foo" +p'
[ 203.900581] dyndbg: read 26 bytes from userspace
[ 203.900883] dyndbg: query 0: "format "find-me: " mod:*
[ 203.901118] dyndbg: unclosed quote: find-me:
[ 203.901355] dyndbg: tokenize failed
[ 203.901529] dyndbg: query 1: "foo" +p" mod:*
[ 203.901957] dyndbg: split into words: "foo"" "+p"
[ 203.902243] dyndbg: op='+' flags=0x1 maskp=0xffffffff
[ 203.902458] dyndbg: expecting pairs of match-spec <value>
[ 203.902703] dyndbg: query parse failed
[ 203.902871] dyndbg: processed 2 queries, with 0 matches, 2 errs
bash: echo: write error: Invalid argument
The '%' splits the input into 2 queries, and both fail. Given the
limited utility of matching against the working parts of a format
string "foo: %d bar %s", nothing is actually lost here.
Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>
---
lib/dynamic_debug.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index c1bc728cb050..625838bd74aa 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -596,7 +596,7 @@ static int ddebug_exec_queries(char *query, const char *modname)
int i, errs = 0, exitcode = 0, rc, nfound = 0;
for (i = 0; query; query = split) {
- split = strpbrk(query, ";\n");
+ split = strpbrk(query, "%;\n");
if (split)
*split++ = '\0';
--
2.44.0
