[PATCH 3/5 maint] Fix checkout of large files to network shares on Windows XP
From: Johannes Sixt <hidden>
Date: 2016-06-15 22:48:49
Subsystem:
the rest · Maintainer:
Linus Torvalds
From: René Scharfe <redacted> Bigger writes to network drives on Windows XP fail. Cap them at 31MB to allow them to succeed. Callers need to be prepared for write() calls that do less work than requested anyway. On local drives, write() calls are translated to WriteFile() calls with a cap of 64KB on Windows XP and 256KB on Vista. Thus a cap of 31MB won't affect the number of WriteFile() calls which do the actual work. There's still room for some other version of Windows to use a chunk size of 1MB without increasing the number of system calls. Signed-off-by: Rene Scharfe <redacted> Signed-off-by: Johannes Sixt <redacted> --- Again, I've used this patch in production with smaller repositories, and it worked flawlessly. compat/mingw.c | 17 +++++++++++++++++ compat/mingw.h | 3 +++ t/t5705-clone-2gb.sh | 12 +++++++++--- 3 files changed, 29 insertions(+), 3 deletions(-)
diff --git a/compat/mingw.c b/compat/mingw.c
index f90a114..9a8e336 100644
--- a/compat/mingw.c
+++ b/compat/mingw.c@@ -140,6 +140,23 @@ int mingw_open (const char *filename, int oflags, ...) return fd; } +#undef write +ssize_t mingw_write(int fd, const void *buf, size_t count) +{ + /* + * While write() calls to a file on a local disk are translated + * into WriteFile() calls with a maximum size of 64KB on Windows + * XP and 256KB on Vista, no such cap is placed on writes to + * files over the network on Windows XP. Unfortunately, there + * seems to be a limit of 32MB-28KB on X64 and 64MB-32KB on x86; + * bigger writes fail on Windows XP. + * So we cap to a nice 31MB here to avoid write failures over + * the net without changing the number of WriteFile() calls in + * the local case. + */ + return write(fd, buf, min(count, 31 * 1024 * 1024)); +} + #undef fopen FILE *mingw_fopen (const char *filename, const char *otype) {
diff --git a/compat/mingw.h b/compat/mingw.h
index a6b8778..f465566 100644
--- a/compat/mingw.h
+++ b/compat/mingw.h@@ -170,6 +170,9 @@ int link(const char *oldpath, const char *newpath); int mingw_open (const char *filename, int oflags, ...); #define open mingw_open +ssize_t mingw_write(int fd, const void *buf, size_t count); +#define write mingw_write + FILE *mingw_fopen (const char *filename, const char *otype); #define fopen mingw_fopen
diff --git a/t/t5705-clone-2gb.sh b/t/t5705-clone-2gb.sh
index adfaae8..8afbdd4 100755
--- a/t/t5705-clone-2gb.sh
+++ b/t/t5705-clone-2gb.sh@@ -12,7 +12,7 @@ test_expect_success 'setup' ' git config pack.compression 0 && git config pack.depth 0 && - blobsize=$((20*1024*1024)) && + blobsize=$((100*1024*1024)) && blobcount=$((2*1024*1024*1024/$blobsize+1)) && i=1 && (while test $i -le $blobcount
@@ -36,9 +36,15 @@ test_expect_success 'setup' ' ' -test_expect_success 'clone' ' +test_expect_success 'clone - bare' ' - git clone --bare --no-hardlinks . clone + git clone --bare --no-hardlinks . clone-bare + +' + +test_expect_success 'clone - with worktree, file:// protocol' ' + + git clone file://. clone-wt '
--
1.7.1.64.ga1799.dirty