dynamic_debug: tighten up error checking on debug queries

Issue error when a match-spec is given multiple times in a rule.
Previous code kept last one, but was silent about it.  Docs imply only
one is allowed by saying match-specs are ANDed together, given that
module M cannot match both A and B.  Also error when last_line < 1st_line.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Jim Cromie 2011-12-19 17:12:49 -05:00 committed by Greg Kroah-Hartman
parent 5ca7d2a6c5
commit 820874c75e
1 changed files with 33 additions and 6 deletions

View File

@ -276,6 +276,19 @@ static char *unescape(char *str)
return str;
}
static int check_set(const char **dest, char *src, char *name)
{
int rc = 0;
if (*dest) {
rc = -EINVAL;
pr_err("match-spec:%s val:%s overridden by %s",
name, *dest, src);
}
*dest = src;
return rc;
}
/*
* Parse words[] as a ddebug query specification, which is a series
* of (keyword, value) pairs chosen from these possibilities:
@ -287,11 +300,15 @@ static char *unescape(char *str)
* format <escaped-string-to-find-in-format>
* line <lineno>
* line <first-lineno>-<last-lineno> // where either may be empty
*
* Only 1 of each type is allowed.
* Returns 0 on success, <0 on error.
*/
static int ddebug_parse_query(char *words[], int nwords,
struct ddebug_query *query)
{
unsigned int i;
int rc;
/* check we have an even number of words */
if (nwords % 2 != 0)
@ -300,24 +317,32 @@ static int ddebug_parse_query(char *words[], int nwords,
for (i = 0 ; i < nwords ; i += 2) {
if (!strcmp(words[i], "func"))
query->function = words[i+1];
rc = check_set(&query->function, words[i+1], "func");
else if (!strcmp(words[i], "file"))
query->filename = words[i+1];
rc = check_set(&query->filename, words[i+1], "file");
else if (!strcmp(words[i], "module"))
query->module = words[i+1];
rc = check_set(&query->module, words[i+1], "module");
else if (!strcmp(words[i], "format"))
query->format = unescape(words[i+1]);
rc = check_set(&query->format, unescape(words[i+1]),
"format");
else if (!strcmp(words[i], "line")) {
char *first = words[i+1];
char *last = strchr(first, '-');
if (query->first_lineno || query->last_lineno) {
pr_err("match-spec:line given 2 times\n");
return -EINVAL;
}
if (last)
*last++ = '\0';
if (parse_lineno(first, &query->first_lineno) < 0)
return -EINVAL;
if (last != NULL) {
if (last) {
/* range <first>-<last> */
if (parse_lineno(last, &query->last_lineno) < 0)
if (parse_lineno(last, &query->last_lineno)
< query->first_lineno) {
pr_err("last-line < 1st-line\n");
return -EINVAL;
}
} else {
query->last_lineno = query->first_lineno;
}
@ -325,6 +350,8 @@ static int ddebug_parse_query(char *words[], int nwords,
pr_err("unknown keyword \"%s\"\n", words[i]);
return -EINVAL;
}
if (rc)
return rc;
}
if (verbose)