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Re: Infinite loop in cascade_filter_fn()

From
HGHenrik Grubbström <grubba@roxen.com>
Date
Nov 25, 2011, 15:43 UTC
Message-ID
<Pine.GSO.4.63.1111251629500.22588@shipon.roxen.com>
In-Reply-To
<Pine.GSO.4.63.1111231801580.5099@shipon.roxen.com>
On Wed, 23 Nov 2011, Henrik Grubbström wrote:
> Hi.
>
> My git repository walker just got bitten by what seems to be a reasonably new 
> bug in convert.c:cascade_filter_fn() (git 1.7.8.rc3 (gentoo)).

After some tracing, the problem is triggered by the variable "remaining" being set to 1 in the beginning of the cascade_filter_fn() loop, which causes filter "two" to be called with an output buffer size of 1. Filter "two" in this case is lf_to_crlf_filter_fn(), and the next input character is a "\n". lf_to_crlf_filter_fn() wants to convert this to "\r\n", but that doesn't fit into the buffer, so it breaks out and returns zero. Upon seing the zero cascade_filter_fn() thinks all is well, even though nothing has happened, and loops.

The bug is probably that lf_to_crlf_filter_fn() should return non-zero in this case (ie o and/or i being zero).

> Thanks,

-- Henrik Grubbström grubba@roxen.com Roxen Internet Software AB

Previous: Carlos Martín NietoNext: Carlos Martín Nieto
Message 14 of 16 in “Infinite loop in cascade_filter_fn()”
  1. Henrik GrubbströmNov 23, 2011
  2. Carlos Martín NietoNov 25, 2011
  3. Carlos Martín NietoNov 25, 2011
  4. Henrik GrubbströmNov 25, 2011
  5. Carlos Martín NietoNov 25, 2011
  6. Junio C HamanoNov 26, 2011
  7. Carlos Martín NietoNov 28, 2011
  8. Junio C HamanoNov 28, 2011
  9. Junio C HamanoDec 16, 2011
  10. lf_to_crlf_filter(): tell the caller we added "\n" when drainingJunio C Hamano, Dec 16, 2011
  11. Henrik GrubbströmDec 19, 2011
  12. Junio C HamanoDec 19, 2011
  13. Carlos Martín NietoDec 19, 2011
  14. Henrik GrubbströmNov 25, 2011
  15. Carlos Martín NietoNov 25, 2011
  16. Henrik GrubbströmNov 25, 2011

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