[PATCH 14/14] env: Use static_assert() to check if default_environment is too large

Marek Behún
2021-10-22T13:57:39Z

From: Marek Behún <marek.behun@nic.cz>

Check sizeof(default_environment) against ENV_SIZE in a static_assert()
instead of runtime.
Only check if !USE_HOSTCC (for in fw_env tool ENV_SIZE expands to a
variable, and cannot be checked statically) nad
!DEFAULT_ENV_INSTANCE_EMBEDDED, for in that case the default_environment
variable is not set.

Signed-off-by: Marek Behún <marek.behun@nic.cz>
---
env/common.c | 5 -----
include/env_default.h | 6 ++++++
2 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/env/common.c b/env/common.c
index 664d2e688e..99729ca002 100644
--- a/env/common.c
+++ b/env/common.c
@@ -247,11 +247,6 @@ char *env_get_default(const char *name)

void env_set_default(const char *s, int flags)
{
- if (sizeof(default_environment) > ENV_SIZE) {
- puts("*** Error - default environment is too large\n\n");
- return;
- }
-
if (s) {
if ((flags & H_INTERACTIVE) == 0) {
printf("*** Warning - %s, "
diff --git a/include/env_default.h b/include/env_default.h
index a6724719ec..23430dc70d 100644
--- a/include/env_default.h
+++ b/include/env_default.h
@@ -121,3 +121,9 @@ const char default_environment[] = {
}
#endif
};
+
+#if !defined(USE_HOSTCC) && !defined(DEFAULT_ENV_INSTANCE_EMBEDDED)
+#include <env_internal.h>
+static_assert(sizeof(default_environment) <= ENV_SIZE,
+ "Default environment is too large");
+#endif
--
2.32.0