introduce MAX_D2STRING_CHARS instead of 128 const (#10487)

There are a few places that use a hard coded const of 128 to allocate a buffer for d2string.
Replace these with a clear macro.
Note that In theory, converting double into string could take as much as nearly 400 chars,
but since d2string uses `%g` and not `%f`, it won't pass some 40 chars.

unrelated:
restore some changes to auto generated commands.c that got accidentally reverted in #10293

1 files changed, 10 insertions, 1 deletions

diff --git a/src/util.h b/src/util.h
index c81db5d16..d2780e00e 100644
--- a/src/util.h
+++ b/src/util.h
@@ -34,10 +34,19 @@
 #include "sds.h"
 
 /* The maximum number of characters needed to represent a long double
- * as a string (long double has a huge range).
+ * as a string (long double has a huge range of some 4952 chars, see LDBL_MAX).
  * This should be the size of the buffer given to ld2string */
 #define MAX_LONG_DOUBLE_CHARS 5*1024
 
+/* The maximum number of characters needed to represent a double
+ * as a string (double has a huge range of some 328 chars, see DBL_MAX).
+ * This should be the size of the buffer for sprintf with %f */
+#define MAX_DOUBLE_CHARS 400
+
+/* The maximum number of characters needed to for d2string call.
+ * Since it uses %g and not %f, some 40 chars should be enough. */
+#define MAX_D2STRING_CHARS 128
+
 /* Bytes needed for long -> str + '\0' */
 #define LONG_STR_SIZE      21