Fixes bug in strlower_libc_sb()

Поиск
Список
Период
Сортировка
От Chao Li
Тема Fixes bug in strlower_libc_sb()
Дата
Msg-id CAEoWx2mW0P8CByavV58zm3=eb2MQHaKOcDEF5B2UJYRyC2c3ig@mail.gmail.com
обсуждение исходный текст
Ответы Re: Fixes bug in strlower_libc_sb()
Список pgsql-hackers
Hi Hackers,

While reviewing Jeff's patch [1], I found this bug in strlower_libc_sb():

```
static size_t
strlower_libc_sb(char *dest, size_t destsize, const char *src, ssize_t srclen,
pg_locale_t locale)
{
if (srclen < 0)
srclen = strlen(src);

if (srclen + 1 <= destsize)
{
locale_t loc = locale->lt;
char   *p;

if (srclen + 1 > destsize)  <== This check will never be true
return srclen;
```

So I removed the useless check in the patch.

I also noticed strlower_libc_sb’s behavior is different from unicode_strlower(), where the function comment says:

```
* Result string is stored in dst, truncating if larger than dstsize. If
* dstsize is greater than the result length, dst will be NUL-terminated;
* otherwise not.
```

And Jeff’s new code in [1] matches the description. The behavior is like trying the best to copy as many chars as possible, if not enough space in dest, then NULL-terminator can be omitted. But the current behavior of strlower_libc_sb that only copies data to dest when dest has enough space for src and NULL-terminator.

So I updated strlower_libc_sb(), strtitle_libc_sb() and strupper_libc_sb() to comply with the behavior in this patch as well. “Make check” passed from my side, so the patch doesn't seem to break anything.



Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/




Вложения

В списке pgsql-hackers по дате отправления: