lib: errno: avoid error format-overflow
In cmd/regulator.c an error occurs with GCC 9.2.1 if CONFIG_ERRNO_STR is
not defined:
cmd/regulator.c: In function ‘failure’:
cmd/regulator.c:20:2: error: ‘%s’ directive argument is null
[-Werror=format-overflow=]
20 | printf("Error: %d (%s)\n", ret, errno_str(ret));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In function ‘constraint’,
inlined from ‘constraint’ at cmd/regulator.c:111:12:
cmd/regulator.c:115:3: error: ‘%s’ directive argument is null
[-Werror=format-overflow=]
115 | printf(" %s (err: %d)\n", errno_str(val), val);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
errno_str() should return a valid string instead of NULL if
CONFIG_ERRNO_STR is not defined.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/include/errno.h b/include/errno.h
index ccb7869..3af539b 100644
--- a/include/errno.h
+++ b/include/errno.h
@@ -12,12 +12,21 @@
#define __set_errno(val) do { errno = val; } while (0)
+/**
+ * errno_str() - get description for error number
+ *
+ * @errno: error number (negative in case of error)
+ * Return: string describing the error. If CONFIG_ERRNO_STR is not
+ * defined an empty string is returned.
+ */
#ifdef CONFIG_ERRNO_STR
const char *errno_str(int errno);
#else
+static const char error_message[] = "";
+
static inline const char *errno_str(int errno)
{
- return 0;
+ return error_message;
}
#endif
#endif /* _ERRNO_H */