Re: [PATCH v2 2/2] grep: stop looking at random places for .gitattributes
From: Johannes Sixt <hidden>
Date: 2016-06-15 22:55:03
Subsystem:
the rest · Maintainer:
Linus Torvalds
Possibly related (same subject, not in this thread)
- 2016-06-15 · Re: [PATCH v2 2/2] grep: stop looking at random places for .gitattributes · Junio C Hamano <hidden>
- 2016-06-15 · Re: [PATCH v2 2/2] grep: stop looking at random places for .gitattributes · Johannes Sixt <hidden>
- 2016-06-15 · Re: [PATCH v2 2/2] grep: stop looking at random places for .gitattributes · Johannes Sixt <hidden>
- 2016-06-15 · Re: [PATCH v2 2/2] grep: stop looking at random places for .gitattributes · Junio C Hamano <hidden>
- 2016-06-15 · [PATCH v2 2/2] grep: stop looking at random places for .gitattributes · Nguyễn Thái Ngọc Duy <hidden>
Am 10/16/2012 8:39, schrieb Johannes Sixt:
Am 10/15/2012 18:54, schrieb Junio C Hamano:quoted
Ideally, that earlier workaround should have done a logica equivalent of: ... and did so not in-line at the calling site but in a compat/ wrapper for fflush() to eliminate the need for the ifdef.Fair enough.quoted
quoted
But reverting the EINVAL check from write_or_die.c is out of question, because that handles a real case.Correction: I can't reproduce the error messages that this was working around anymore in a brief test. I'll revert the check locally and see what happens.
The error is reproducible with this command on Windows: $ git rev-list HEAD | sed 1q 42b333d8bb8709dfc5783dd4c44bdb6012c2c17d fatal: write failure on 'stdout': Invalid argument Let's do as you suggested.
--- 8< ---From: Johannes Sixt <redacted> Subject: [PATCH] maybe_flush_or_die: move a too-loose Windows specific error check to compat Commit b2f5e268 (Windows: Work around an oddity when a pipe with no reader is written to) introduced a check for EINVAL after fflush() to fight spurious "Invalid argument" errors on Windows when a pipe was broken. But this check may hide real errors on systems that do not have the this odd behavior. Introduce an fflush wrapper in compat/mingw.* so that the treatment is only applied on Windows. Signed-off-by: Johannes Sixt <redacted> --- compat/mingw.c | 22 ++++++++++++++++++++++ compat/mingw.h | 3 +++ write_or_die.c | 7 +------ 3 files changed, 26 insertions(+), 6 deletions(-)
diff --git a/compat/mingw.c b/compat/mingw.c
index afc892d..4e63838 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c@@ -335,6 +335,28 @@ FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream) return freopen(filename, otype, stream); } +#undef fflush +int mingw_fflush(FILE *stream) +{ + int ret = fflush(stream); + + /* + * write() is used behind the scenes of stdio output functions. + * Since git code does not check for errors after each stdio write + * operation, it can happen that write() is called by a later + * stdio function even if an earlier write() call failed. In the + * case of a pipe whose readable end was closed, only the first + * call to write() reports EPIPE on Windows. Subsequent write() + * calls report EINVAL. It is impossible to notice whether this + * fflush invocation triggered such a case, therefore, we have to + * catch all EINVAL errors whole-sale. + */ + if (ret && errno == EINVAL) + errno = EPIPE; + + return ret; +} + /* * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC. * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
diff --git a/compat/mingw.h b/compat/mingw.h
index 61a6521..eeb08d1 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h@@ -185,6 +185,9 @@ FILE *mingw_fopen (const char *filename, const char *otype); FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream); #define freopen mingw_freopen +int mingw_fflush(FILE *stream); +#define fflush mingw_fflush + char *mingw_getcwd(char *pointer, int len); #define getcwd mingw_getcwd
diff --git a/write_or_die.c b/write_or_die.c
index d45b536..960f448 100644
--- a/write_or_die.c
+++ b/write_or_die.c@@ -34,12 +34,7 @@ void maybe_flush_or_die(FILE *f, const char *desc) return; } if (fflush(f)) { - /* - * On Windows, EPIPE is returned only by the first write() - * after the reading end has closed its handle; subsequent - * write()s return EINVAL. - */ - if (errno == EPIPE || errno == EINVAL) + if (errno == EPIPE) exit(0); die_errno("write failure on '%s'", desc); }
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1.8.0.rc2.1248.g3f5b13f