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| author | Junio C Hamano <gitster@pobox.com> | 2022-04-06 13:01:54 -0700 |
|---|---|---|
| committer | Junio C Hamano <gitster@pobox.com> | 2022-04-06 13:01:54 -0700 |
| commit | fca85986bb936346d362c4802ebce5692fd257ee (patch) | |
| tree | f7223aef7eb92a5ae483fe86b790c207f1f24043 /wrapper.c | |
| parent | b896f729e240d250cf56899e6a0073f6aa469f5d (diff) | |
| parent | 2e37594797155e5d6134db3ce1e23bf42045934b (diff) | |
| download | git-fca85986bb936346d362c4802ebce5692fd257ee.tar.gz | |
Merge branch 'ns/core-fsyncmethod' into ns/batch-fsync
* ns/core-fsyncmethod:
configure.ac: fix HAVE_SYNC_FILE_RANGE definition
core.fsyncmethod: correctly camel-case warning message
core.fsync: fix incorrect expression for default configuration
core.fsync: documentation and user-friendly aggregate options
core.fsync: new option to harden the index
core.fsync: add configuration parsing
core.fsync: introduce granular fsync control infrastructure
core.fsyncmethod: add writeout-only mode
wrapper: make inclusion of Windows csprng header tightly scoped
Diffstat (limited to 'wrapper.c')
| -rw-r--r-- | wrapper.c | 71 |
1 files changed, 71 insertions, 0 deletions
@@ -4,6 +4,13 @@ #include "cache.h" #include "config.h" +#ifdef HAVE_RTLGENRANDOM +/* This is required to get access to RtlGenRandom. */ +#define SystemFunction036 NTAPI SystemFunction036 +#include <NTSecAPI.h> +#undef SystemFunction036 +#endif + static int memory_limit_check(size_t size, int gentle) { static size_t limit = 0; @@ -539,6 +546,70 @@ int xmkstemp_mode(char *filename_template, int mode) return fd; } +/* + * Some platforms return EINTR from fsync. Since fsync is invoked in some + * cases by a wrapper that dies on failure, do not expose EINTR to callers. + */ +static int fsync_loop(int fd) +{ + int err; + + do { + err = fsync(fd); + } while (err < 0 && errno == EINTR); + return err; +} + +int git_fsync(int fd, enum fsync_action action) +{ + switch (action) { + case FSYNC_WRITEOUT_ONLY: + +#ifdef __APPLE__ + /* + * On macOS, fsync just causes filesystem cache writeback but + * does not flush hardware caches. + */ + return fsync_loop(fd); +#endif + +#ifdef HAVE_SYNC_FILE_RANGE + /* + * On linux 2.6.17 and above, sync_file_range is the way to + * issue a writeback without a hardware flush. An offset of + * 0 and size of 0 indicates writeout of the entire file and the + * wait flags ensure that all dirty data is written to the disk + * (potentially in a disk-side cache) before we continue. + */ + + return sync_file_range(fd, 0, 0, SYNC_FILE_RANGE_WAIT_BEFORE | + SYNC_FILE_RANGE_WRITE | + SYNC_FILE_RANGE_WAIT_AFTER); +#endif + +#ifdef fsync_no_flush + return fsync_no_flush(fd); +#endif + + errno = ENOSYS; + return -1; + + case FSYNC_HARDWARE_FLUSH: + /* + * On macOS, a special fcntl is required to really flush the + * caches within the storage controller. As of this writing, + * this is a very expensive operation on Apple SSDs. + */ +#ifdef __APPLE__ + return fcntl(fd, F_FULLFSYNC); +#else + return fsync_loop(fd); +#endif + default: + BUG("unexpected git_fsync(%d) call", action); + } +} + static int warn_if_unremovable(const char *op, const char *file, int rc) { int err; |