[PATCH v10 03/27] kallsyms: add static relationship between `KSYM_NAME_LEN{,_BUFFER}`

From: Miguel Ojeda
Date: Tue Sep 27 2022 - 09:16:48 EST


This adds a static assert to ensure `KSYM_NAME_LEN_BUFFER`
gets updated when `KSYM_NAME_LEN` changes.

The relationship used is one that keeps the new size (512+1)
close to the original buffer size (500).

Co-developed-by: Boqun Feng <boqun.feng@xxxxxxxxx>
Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
---
scripts/kallsyms.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index 25e2fe5fbcd4..411ff5058b51 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -32,8 +32,18 @@

#define KSYM_NAME_LEN 128

-/* A substantially bigger size than the current maximum. */
-#define KSYM_NAME_LEN_BUFFER 499
+/*
+ * A substantially bigger size than the current maximum.
+ *
+ * It cannot be defined as an expression because it gets stringified
+ * for the fscanf() format string. Therefore, a _Static_assert() is
+ * used instead to maintain the relationship with KSYM_NAME_LEN.
+ */
+#define KSYM_NAME_LEN_BUFFER 512
+_Static_assert(
+ KSYM_NAME_LEN_BUFFER == KSYM_NAME_LEN * 4,
+ "Please keep KSYM_NAME_LEN_BUFFER in sync with KSYM_NAME_LEN"
+);

struct sym_entry {
unsigned long long addr;
--
2.37.3