[PATCH 3/3] tools/mm: grow the record list instead of guessing its size

[Henrique Godoy]

main() sizes the array of records with st.st_size / 100, and add_list()
refuses to go past it with "max_size too small??".  A dump whose records
are shorter than 100 bytes holds more records than that, so a valid input
is rejected and no output is written:

  $ ./page_owner_sort dump.txt out.txt
  max_size too small??

Keep the guess as a starting point and grow the array with realloc().

Co-developed-by: Pierre <pierre@xxxxxxxxxxxx>
Signed-off-by: Pierre <pierre@xxxxxxxxxxxx>
Signed-off-by: Henrique Godoy <henrique.godoy@xxxxxxxxxxxx>
---
 tools/mm/page_owner_sort.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/tools/mm/page_owner_sort.c b/tools/mm/page_owner_sort.c
index a042bf1..5b51cff 100644
--- a/tools/mm/page_owner_sort.c
+++ b/tools/mm/page_owner_sort.c
@@ -571,8 +571,16 @@ static bool add_list(char *buf, int len, char *ext_buf)
 	enum FILTER_RESULT filter_result;

 	if (list_size == max_size) {
-		fprintf(stderr, "max_size too small??\n");
-		return false;
+		struct block_list *grown;
+		int new_size = max_size ? max_size * 2 : 64;
+
+		grown = realloc(list, new_size * sizeof(*list));
+		if (!grown) {
+			fprintf(stderr, "Out of memory\n");
+			return false;
+		}
+		list = grown;
+		max_size = new_size;
 	}
 	filter_result = filter_record(buf);
 	if (filter_result == FILTER_ERROR) {
@@ -952,7 +960,8 @@ int main(int argc, char **argv)
 		goto out_module;

 	fstat(fileno(fin), &st);
-	max_size = st.st_size / 100; /* hack ... */
+	/* the guess is only a starting point, add_list() grows the list */
+	max_size = st.st_size / 100 ?: 1;

 	list = malloc(max_size * sizeof(*list));
 	buf = malloc(BUF_SIZE);
-- 
2.39.5