compat: introduce on_disk_bytes()

Some platforms do not have st_blocks member in "struct stat"; mingw
already emulates it by rounding it up to closest 512-byte blocks (even
though it could overcount when a file has holes).

The reason to use the member is only to figure out how many kilobytes the
files occupy on-disk, so give a helper function in git-compat-util.h to
compute this value.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Acked-by: Johannes Sixt <johannes.sixt@telecom.at>

Makefile

@@ -124,6 +124,9 @@ all::
 # Define USE_STDEV below if you want git to care about the underlying device
 # change being considered an inode change from the update-index perspective.
 #
+# Define NO_ST_BLOCKS_IN_STRUCT_STAT if your platform does not have st_blocks
+# field that counts the on-disk footprint in 512-byte blocks.
+#
 # Define ASCIIDOC8 if you want to format documentation with AsciiDoc 8
 #
 # Define DOCBOOK_XSL_172 if you want to format man pages with DocBook XSL v1.72.
@@ -749,6 +752,7 @@ ifneq (,$(findstring MINGW,$(uname_S)))
 	NO_SVN_TESTS = YesPlease
 	NO_PERL_MAKEMAKER = YesPlease
 	NO_POSIX_ONLY_PROGRAMS = YesPlease
+	NO_ST_BLOCKS_IN_STRUCT_STAT = YesPlease
 	COMPAT_CFLAGS += -D__USE_MINGW_ACCESS -DNOGDI -Icompat
 	COMPAT_CFLAGS += -DSNPRINTF_SIZE_CORR=1
 	COMPAT_CFLAGS += -DSTRIP_EXTENSION=\".exe\"
@@ -863,6 +867,9 @@ endif
 ifdef NO_D_INO_IN_DIRENT
 	BASIC_CFLAGS += -DNO_D_INO_IN_DIRENT
 endif
+ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
+	BASIC_CFLAGS += -DNO_ST_BLOCKS_IN_STRUCT_STAT
+endif
 ifdef NO_C99_FORMAT
 	BASIC_CFLAGS += -DNO_C99_FORMAT
 endif

builtin-count-objects.c

@@ -43,7 +43,7 @@ static void count_objects(DIR *d, char *path, int len, int verbose,
 			if (lstat(path, &st) || !S_ISREG(st.st_mode))
 				bad = 1;
 			else
-				(*loose_size) += xsize_t(st.st_blocks);
+				(*loose_size) += xsize_t(on_disk_bytes(st));
 		}
 		if (bad) {
 			if (verbose) {
@@ -115,7 +115,7 @@ int cmd_count_objects(int argc, const char **argv, const char *prefix)
 			num_pack++;
 		}
 		printf("count: %lu\n", loose);
-		printf("size: %lu\n", loose_size / 2);
+		printf("size: %lu\n", loose_size / 1024);
 		printf("in-pack: %lu\n", packed);
 		printf("packs: %lu\n", num_pack);
 		printf("prune-packable: %lu\n", packed_loose);

compat/mingw.c

@@ -31,11 +31,6 @@ static inline time_t filetime_to_time_t(const FILETIME *ft)
 	return (time_t)winTime;
 }
 
-static inline size_t size_to_blocks(size_t s)
-{
-	return (s+511)/512;
-}
-
 extern int _getdrive( void );
 /* We keep the do_lstat code in a separate function to avoid recursion.
  * When a path ends with a slash, the stat will fail with ENOENT. In
@@ -59,7 +54,6 @@ static int do_lstat(const char *file_name, struct stat *buf)
 		buf->st_uid = 0;
 		buf->st_mode = fMode;
 		buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
-		buf->st_blocks = size_to_blocks(buf->st_size);
 		buf->st_dev = _getdrive() - 1;
 		buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 		buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
@@ -142,7 +136,6 @@ int mingw_fstat(int fd, struct mingw_stat *buf)
 		buf->st_uid = st.st_uid;
 		buf->st_mode = st.st_mode;
 		buf->st_size = st.st_size;
-		buf->st_blocks = size_to_blocks(buf->st_size);
 		buf->st_dev = st.st_dev;
 		buf->st_atime = st.st_atime;
 		buf->st_mtime = st.st_mtime;
@@ -164,7 +157,6 @@ int mingw_fstat(int fd, struct mingw_stat *buf)
 		buf->st_uid = 0;
 		buf->st_mode = fMode;
 		buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
-		buf->st_blocks = size_to_blocks(buf->st_size);
 		buf->st_dev = _getdrive() - 1;
 		buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
 		buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));

compat/mingw.h

@@ -169,7 +169,6 @@ struct mingw_stat {
 	time_t st_mtime, st_atime, st_ctime;
 	unsigned st_dev, st_ino, st_uid, st_gid;
 	size_t st_size;
-	size_t st_blocks;
 };
 int mingw_lstat(const char *file_name, struct mingw_stat *buf);
 int mingw_fstat(int fd, struct mingw_stat *buf);

git-compat-util.h

@@ -192,6 +192,12 @@ extern int git_munmap(void *start, size_t length);
 
 #endif /* NO_MMAP */
 
+#ifdef NO_ST_BLOCKS_IN_STRUCT_STAT
+#define on_disk_bytes(st) ((st).st_size)
+#else
+#define on_disk_bytes(st) ((st).st_blocks * 512)
+#endif
+
 #define DEFAULT_PACKED_GIT_LIMIT \
 	((1024L * 1024L) * (sizeof(void*) >= 8 ? 8192 : 256))