@@ -389,16 +389,40 @@ void tracefs_option_clear(struct tracefs_options_mask *options, enum tracefs_opt
options->mask &= ~(1ULL << (id - 1));
}
+static void add_errors(const char ***errs, const char *filter, int ret)
+{
+ const char **e;
+
+ if (!errs)
+ return;
+
+ /* Negative is passed in */
+ ret = -ret;
+ e = *errs;
+
+ /* If this previously failed to allocate stop processing */
+ if (!e && ret)
+ return;
+
+ /* Add 2, one for the new entry, and one for NULL */
+ e = realloc(e, sizeof(*e) * (ret + 2));
+ if (!e) {
+ free(*errs);
+ *errs = NULL;
+ return;
+ }
+ e[ret] = filter;
+ e[ret + 1] = NULL;
+ *errs = e;
+}
+
static int controlled_write(int fd, const char **filters,
const char *module, const char ***errs)
{
- const char **temp = NULL;
- const char **e = NULL;
char *each_str = NULL;
int write_size = 0;
int size = 0;
int ret = 0;
- int j = 0;
int i;
for (i = 0; filters[i]; i++) {
@@ -412,34 +436,11 @@ static int controlled_write(int fd, const char **filters,
}
size = write(fd, each_str, write_size);
/* compare written bytes*/
- if (size < write_size) {
- if (errs) {
- temp = realloc(e, (j + 1) * (sizeof(char *)));
- if (!temp) {
- free(e);
- ret = 1;
- goto error;
- } else
- e = temp;
-
- e[j++] = filters[i];
- ret -= 1;
- }
- }
+ if (size < write_size)
+ add_errors(errs, filters[i], ret--);
free(each_str);
each_str = NULL;
}
- if (errs) {
- temp = realloc(e, (j + 1) * (sizeof(char *)));
- if (!temp) {
- free(e);
- ret = 1;
- goto error;
- } else
- e = temp;
- e[j] = NULL;
- *errs = e;
- }
error:
if (each_str)
free(each_str);
@@ -496,6 +497,10 @@ int tracefs_function_filter(struct tracefs_instance *instance, const char **filt
if (fd < 0)
return 1;
+ /* Make sure errs is NULL to start with, realloc() depends on it. */
+ if (errs)
+ *errs = NULL;
+
ret = controlled_write(fd, filters, module, errs);
close(fd);