Record ns-timestamps if possible, but do not use it without USE_NSEC
Traditionally, the lack of USE_NSEC meant "do not record nor use the nanosecond resolution part of the file timestamps". To avoid problems on filesystems that lose the ns part when the metadata is flushed to the disk and then later read back in, disabling USE_NSEC has been a good idea in general. If you are on a filesystem without such an issue, it does not hurt to read and store them in the cached stat data in the index entries even if your git is compiled without USE_NSEC. The index left with such a version of git can be read by git compiled with USE_NSEC and it can make use of the nanosecond part to optimize the check to see if the path on the filesystem hsa been modified since we last looked at. Signed-off-by: Junio C Hamano <gitster@pobox.com>
Kjetil Barvik committed
Mar 4, 2009 at 18:47 UTC
c06ff4908bf9ad8bf2448439a3574321c9399b17
5 files changed
+22
-30
Makefile
+8
@@ -126,6 +126,9 @@ all::
126
# randomly break unless your underlying filesystem supports those sub-second
127
# times (my ext3 doesn't).
128
#
129
+# Define NO_NSEC if your "struct stat" does not have "st_ctim.tv_nsec"
130
+# available. This automatically turns USE_NSEC off.
131
+#
132
# Define USE_STDEV below if you want git to care about the underlying device
133
# change being considered an inode change from the update-index perspective.
134
#
@@ -737,6 +740,7 @@ ifeq ($(uname_S),AIX)
740
NO_MEMMEM = YesPlease
741
NO_MKDTEMP = YesPlease
742
NO_STRLCPY = YesPlease
743
+ NO_NSEC = YesPlease
744
FREAD_READS_DIRECTORIES = UnfortunatelyYes
745
INTERNAL_QSORT = UnfortunatelyYes
746
NEEDS_LIBICONV=YesPlease
@@ -802,6 +806,7 @@ ifneq (,$(findstring MINGW,$(uname_S)))
806
RUNTIME_PREFIX = YesPlease
807
NO_POSIX_ONLY_PROGRAMS = YesPlease
808
NO_ST_BLOCKS_IN_STRUCT_STAT = YesPlease
809
+ NO_NSEC = YesPlease
810
COMPAT_CFLAGS += -D__USE_MINGW_ACCESS -DNOGDI -Icompat -Icompat/regex -Icompat/fnmatch
811
COMPAT_CFLAGS += -DSNPRINTF_SIZE_CORR=1
812
COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
@@ -923,6 +928,9 @@ endif
928
ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
929
BASIC_CFLAGS += -DNO_ST_BLOCKS_IN_STRUCT_STAT
930
endif
931
+ifdef NO_NSEC
932
+ BASIC_CFLAGS += -DNO_NSEC
933
+endif
934
ifdef NO_C99_FORMAT
935
BASIC_CFLAGS += -DNO_C99_FORMAT
936
endif
builtin-fetch-pack.c
+1
-3
@@ -801,9 +801,7 @@ struct ref *fetch_pack(struct fetch_pack_args *my_args,
801
int fd;
802
803
mtime.sec = st.st_mtime;
804
-#ifdef USE_NSEC
805
- mtime.nsec = st.st_mtim.tv_nsec;
806
-#endif
804
+ mtime.nsec = ST_MTIME_NSEC(st);
805
if (stat(shallow, &st)) {
806
if (mtime.sec)
807
die("shallow file was removed during fetch");
git-compat-util.h
+9
@@ -384,4 +384,13 @@ void git_qsort(void *base, size_t nmemb, size_t size,
384
# define FORCE_DIR_SET_GID 0
385
#endif
386
387
+#ifdef NO_NSEC
388
+#undef USE_NSEC
389
+#define ST_CTIME_NSEC(st) 0
390
+#define ST_MTIME_NSEC(st) 0
391
+#else
392
+#define ST_CTIME_NSEC(st) ((unsigned int)((st).st_ctim.tv_nsec))
393
+#define ST_MTIME_NSEC(st) ((unsigned int)((st).st_mtim.tv_nsec))
394
+#endif
395
+
396
#endif
read-cache.c
+4
-25
@@ -69,13 +69,8 @@ void fill_stat_cache_info(struct cache_entry *ce, struct stat *st)
69
{
70
ce->ce_ctime.sec = (unsigned int)st->st_ctime;
71
ce->ce_mtime.sec = (unsigned int)st->st_mtime;
72
-#ifdef USE_NSEC
73
- ce->ce_ctime.nsec = (unsigned int)st->st_ctim.tv_nsec;
74
- ce->ce_mtime.nsec = (unsigned int)st->st_mtim.tv_nsec;
75
-#else
76
- ce->ce_ctime.nsec = 0;
77
- ce->ce_mtime.nsec = 0;
78
-#endif
72
+ ce->ce_ctime.nsec = ST_CTIME_NSEC(*st);
73
+ ce->ce_mtime.nsec = ST_MTIME_NSEC(*st);
74
ce->ce_dev = st->st_dev;
75
ce->ce_ino = st->st_ino;
76
ce->ce_uid = st->st_uid;
@@ -1183,13 +1178,8 @@ static void convert_from_disk(struct ondisk_cache_entry *ondisk, struct cache_en
1178
1179
ce->ce_ctime.sec = ntohl(ondisk->ctime.sec);
1180
ce->ce_mtime.sec = ntohl(ondisk->mtime.sec);
1186
-#ifdef USE_NSEC
1181
ce->ce_ctime.nsec = ntohl(ondisk->ctime.nsec);
1182
ce->ce_mtime.nsec = ntohl(ondisk->mtime.nsec);
1189
-#else
1190
- ce->ce_ctime.nsec = 0;
1191
- ce->ce_mtime.nsec = 0;
1192
-#endif
1183
ce->ce_dev = ntohl(ondisk->dev);
1184
ce->ce_ino = ntohl(ondisk->ino);
1185
ce->ce_mode = ntohl(ondisk->mode);
@@ -1309,11 +1299,7 @@ int read_index_from(struct index_state *istate, const char *path)
1299
dst_offset += ce_size(ce);
1300
}
1301
istate->timestamp.sec = st.st_mtime;
1312
-#ifdef USE_NSEC
1313
- istate->timestamp.nsec = (unsigned int)st.st_mtim.tv_nsec;
1314
-#else
1315
- istate->timestamp.nsec = 0;
1316
-#endif
1302
+ istate->timestamp.nsec = ST_MTIME_NSEC(st);
1303
1304
while (src_offset <= mmap_size - 20 - 8) {
1305
/* After an array of active_nr index entries,
@@ -1500,13 +1486,8 @@ static int ce_write_entry(git_SHA_CTX *c, int fd, struct cache_entry *ce)
1486
1487
ondisk->ctime.sec = htonl(ce->ce_ctime.sec);
1488
ondisk->mtime.sec = htonl(ce->ce_mtime.sec);
1503
-#ifdef USE_NSEC
1489
ondisk->ctime.nsec = htonl(ce->ce_ctime.nsec);
1490
ondisk->mtime.nsec = htonl(ce->ce_mtime.nsec);
1506
-#else
1507
- ondisk->ctime.nsec = 0;
1508
- ondisk->mtime.nsec = 0;
1509
-#endif
1491
ondisk->dev = htonl(ce->ce_dev);
1492
ondisk->ino = htonl(ce->ce_ino);
1493
ondisk->mode = htonl(ce->ce_mode);
@@ -1583,9 +1564,7 @@ int write_index(struct index_state *istate, int newfd)
1564
if (ce_flush(&c, newfd) || fstat(newfd, &st))
1565
return -1;
1566
istate->timestamp.sec = (unsigned int)st.st_ctime;
1586
-#ifdef USE_NSEC
1587
- istate->timestamp.nsec = (unsigned int)st.st_ctim.tv_nsec;
1588
-#endif
1567
+ istate->timestamp.nsec = ST_CTIME_NSEC(st);
1568
return 0;
1569
}
1570
unpack-trees.c
-2
@@ -362,9 +362,7 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
362
o->result.initialized = 1;
363
if (o->src_index) {
364
o->result.timestamp.sec = o->src_index->timestamp.sec;
365
-#ifdef USE_NSEC
365
o->result.timestamp.nsec = o->src_index->timestamp.nsec;
367
-#endif
366
}
367
o->merge_size = len;
368