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Re: [PATCH] mingw: emulate write(2) that fails with a EPIPE

From
Junio C Hamano <gitster@pobox.com>
Date
Dec 16, 2015, 18:35 UTC
Message-ID
<xmqq7fkedyx7.fsf@gitster.mtv.corp.google.com>
In-Reply-To
<01da36219c18373f8507e19035e141d7e56b2d18.1450267413.git.johannes.schindelin@gmx.de>
Johannes Schindelin <johannes.schindelin@gmx.de> writes:
Show 9 quoted lines
> On Windows, when writing to a pipe fails, errno is always
> EINVAL. However, Git expects it to be EPIPE.
>
> According to the documentation, there are two cases in which write()
> triggers EINVAL: the buffer is NULL, or the length is odd but the mode
> is 16-bit Unicode (the broken pipe is not mentioned as possible cause).
> Git never sets the file mode to anything but binary, therefore we know
> that errno should actually be EPIPE if it is EINVAL and the buffer is
> not NULL.
Makes sense.
Show 21 quoted lines
>  int mingw_fflush(FILE *stream);
>  #define fflush mingw_fflush
>  
> +static inline ssize_t mingw_write(int fd, const void *buf, size_t len)
> +{
> +	ssize_t result = write(fd, buf, len);
> +
> +	if (result < 0 && errno == EINVAL && buf) {
> +		/* check if fd is a pipe */
> +		HANDLE h = (HANDLE) _get_osfhandle(fd);
> +		if (GetFileType(h) == FILE_TYPE_PIPE)
> +			errno = EPIPE;
> +		else
> +			errno = EINVAL;
> +	}
> +
> +	return result;
> +}
> +
> +#define write mingw_write
> +

It strikes me a bit strange to see this inlined compared to what appears in the context. Shouldn't the implementation be done in compat/mingw.c like all others?

>  int mingw_access(const char *filename, int mode);
>  #undef access
>  #define access mingw_access
Previous: Johannes SchindelinNext: Johannes Schindelin
Message 2 of 13 in “mingw: emulate write(2) that fails with a EPIPE”
  1. mingw: emulate write(2) that fails with a EPIPEJohannes Schindelin, Dec 16, 2015
  2. Junio C HamanoDec 16, 2015
  3. Johannes SchindelinDec 17, 2015
  4. Junio C HamanoDec 17, 2015
  5. Johannes SchindelinDec 17, 2015
  6. Eric SunshineDec 16, 2015
  7. Junio C HamanoDec 16, 2015
  8. Johannes SchindelinDec 17, 2015
  9. mingw: emulate write(2) that fails with a EPIPEJohannes Schindelin, Dec 17, 2015
  10. Junio C HamanoDec 17, 2015
  11. Johannes SchindelinDec 18, 2015
  12. Johannes SixtDec 18, 2015
  13. Junio C HamanoDec 21, 2015

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