Horton

Re: Minor refactorings to eliminate some static buffers

Heikki Linnakangas <hlinnaka@iki.fi>

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From: Heikki Linnakangas <hlinnaka@iki.fi>
To: Andres Freund <andres@anarazel.de>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2024-08-06T20:12:12Z
Lists: pgsql-hackers 
On 06/08/2024 18:52, Andres Freund wrote:
> On 2024-08-06 18:13:56 +0300, Heikki Linnakangas wrote:
>> diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c
>> index 702a6c3a0b..2732d6bfc9 100644
>> --- a/src/backend/tcop/utility.c
>> +++ b/src/backend/tcop/utility.c
>> @@ -1155,7 +1155,7 @@ ProcessUtilitySlow(ParseState *pstate,
>>   						{
>>   							CreateStmt *cstmt = (CreateStmt *) stmt;
>>   							Datum		toast_options;
>> -							static char *validnsps[] = HEAP_RELOPT_NAMESPACES;
>> +							const char *validnsps[] = HEAP_RELOPT_NAMESPACES;
>>   
>>   							/* Remember transformed RangeVar for LIKE */
>>   							table_rv = cstmt->relation;
> 
> In the other places you used "const char * const", here just "const char *" - it
> doesn't look like that's a required difference?

Just an oversight.

I went back and forth on whether to use plain "char *validnps[]", "const 
char *validnsps[]" or "const char *const validnsps[]". The first form 
doesn't convey the fact it's read-only, like the "static" used to. The 
second form hints that, but only for the strings, not for the pointers 
in the array. The last form is what we want, but it's a bit verbose and 
ugly. I chose the last form in the end, but missed this one.

Fixed that and pushed. Thanks!

-- 
Heikki Linnakangas
Neon (https://neon.tech)

Commits

  1. Use psprintf to simplify gtsvectorout()

  2. Constify fields and parameters in spell.c

  3. Mark misc static global variables as const

  4. Make nullSemAction const, add 'const' decorators to related functions

  5. Turn a few 'validnsps' static variables into locals

  6. Refactor getWeights to write to caller-supplied buffer

  7. Replace static buf with a stack-allocated one in 'seg' extension

  8. Replace static buf with a stack-allocated one in ReadControlFile

  9. Replace static buf with palloc in str_time()

  10. Replace static bufs with a StringInfo in cash_words()