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[PATCH v2 02/10] streaming: make streaming-write-entry to be more reusable

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
Mar 4, 2012, 12:59 UTC
Message-ID
<1330865996-2069-3-git-send-email-pclouds@gmail.com>
In-Reply-To
<1330865996-2069-1-git-send-email-pclouds@gmail.com>
From: Junio C Hamano <gitster@pobox.com>

The static function in entry.c takes a cache entry and streams its blob contents to a file in the working tree. Refactor the logic to a new API function stream_blob_to_fd() that takes an object name and an open file descriptor, so that it can be reused by other callers.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
---
 entry.c     |   53 +++++------------------------------------------------
 streaming.c |   55 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
 streaming.h |    2 ++
 3 files changed, 62 insertions(+), 48 deletions(-)
diff --git a/entry.c b/entry.c
index 852fea1..17a6bcc 100644
--- a/entry.c
+++ b/entry.c
@@ -120,58 +120,15 @@ static int streaming_write_entry(struct cache_entry *ce, char *path,
 				 const struct checkout *state, int to_tempfile,
 				 int *fstat_done, struct stat *statbuf)
 {
-	struct git_istream *st;
-	enum object_type type;
-	unsigned long sz;
 	int result = -1;
-	ssize_t kept = 0;
-	int fd = -1;
-
-	st = open_istream(ce->sha1, &type, &sz, filter);
-	if (!st)
-		return -1;
-	if (type != OBJ_BLOB)
-		goto close_and_exit;
+	int fd;
 
 	fd = open_output_fd(path, ce, to_tempfile);
-	if (fd < 0)
-		goto close_and_exit;
-
-	for (;;) {
-		char buf[1024 * 16];
-		ssize_t wrote, holeto;
-		ssize_t readlen = read_istream(st, buf, sizeof(buf));
-
-		if (!readlen)
-			break;
-		if (sizeof(buf) == readlen) {
-			for (holeto = 0; holeto < readlen; holeto++)
-				if (buf[holeto])
-					break;
-			if (readlen == holeto) {
-				kept += holeto;
-				continue;
-			}
-		}
-
-		if (kept && lseek(fd, kept, SEEK_CUR) == (off_t) -1)
-			goto close_and_exit;
-		else
-			kept = 0;
-		wrote = write_in_full(fd, buf, readlen);
-
-		if (wrote != readlen)
-			goto close_and_exit;
-	}
-	if (kept && (lseek(fd, kept - 1, SEEK_CUR) == (off_t) -1 ||
-		     write(fd, "", 1) != 1))
-		goto close_and_exit;
-	*fstat_done = fstat_output(fd, state, statbuf);
-
-close_and_exit:
-	close_istream(st);
-	if (0 <= fd)
+	if (0 <= fd) {
+		result = stream_blob_to_fd(fd, ce->sha1, filter, 1);
+		*fstat_done = fstat_output(fd, state, statbuf);
 		result = close(fd);
+	}
 	if (result && 0 <= fd)
 		unlink(path);
 	return result;
diff --git a/streaming.c b/streaming.c
index 71072e1..7e7ee2b 100644
--- a/streaming.c
+++ b/streaming.c
@@ -489,3 +489,58 @@ static open_method_decl(incore)
 
 	return st->u.incore.buf ? 0 : -1;
 }
+
+
+/****************************************************************
+ * Users of streaming interface
+ ****************************************************************/
+
+int stream_blob_to_fd(int fd, unsigned const char *sha1, struct stream_filter *filter,
+		      int can_seek)
+{
+	struct git_istream *st;
+	enum object_type type;
+	unsigned long sz;
+	ssize_t kept = 0;
+	int result = -1;
+
+	st = open_istream(sha1, &type, &sz, filter);
+	if (!st)
+		return result;
+	if (type != OBJ_BLOB)
+		goto close_and_exit;
+	for (;;) {
+		char buf[1024 * 16];
+		ssize_t wrote, holeto;
+		ssize_t readlen = read_istream(st, buf, sizeof(buf));
+
+		if (!readlen)
+			break;
+		if (can_seek && sizeof(buf) == readlen) {
+			for (holeto = 0; holeto < readlen; holeto++)
+				if (buf[holeto])
+					break;
+			if (readlen == holeto) {
+				kept += holeto;
+				continue;
+			}
+		}
+
+		if (kept && lseek(fd, kept, SEEK_CUR) == (off_t) -1)
+			goto close_and_exit;
+		else
+			kept = 0;
+		wrote = write_in_full(fd, buf, readlen);
+
+		if (wrote != readlen)
+			goto close_and_exit;
+	}
+	if (kept && (lseek(fd, kept - 1, SEEK_CUR) == (off_t) -1 ||
+		     write(fd, "", 1) != 1))
+		goto close_and_exit;
+	result = 0;
+
+ close_and_exit:
+	close_istream(st);
+	return result;
+}
diff --git a/streaming.h b/streaming.h
index 589e857..3e82770 100644
--- a/streaming.h
+++ b/streaming.h
@@ -12,4 +12,6 @@ extern struct git_istream *open_istream(const unsigned char *, enum object_type
 extern int close_istream(struct git_istream *);
 extern ssize_t read_istream(struct git_istream *, char *, size_t);
 
+extern int stream_blob_to_fd(int fd, const unsigned char *, struct stream_filter *, int can_seek);
+
 #endif /* STREAMING_H */
-- 
1.7.8.36.g69ee2
Previous: Junio C HamanoNext: Nguyễn Thái Ngọc Duy
Message 24 of 48 in “Large blob fixes”
  1. 00/11 Large blob fixesNguyễn Thái Ngọc Duy, Feb 27, 2012
  2. 01/11 Add more large blob test casesNguyễn Thái Ngọc Duy, Feb 27, 2012
  3. Peter BaumannFeb 27, 2012
  4. 02/11 Factor out and export large blob writing code to arbitrary file handleNguyễn Thái Ngọc Duy, Feb 27, 2012
  5. Junio C HamanoFeb 27, 2012
  6. Junio C HamanoFeb 27, 2012
  7. 03/11 cat-file: use streaming interface to print blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  8. Junio C HamanoFeb 27, 2012
  9. Nguyen Thai Ngoc DuyFeb 28, 2012
  10. 04/11 parse_object: special code path for blobs to avoid putting whole object in memoryNguyễn Thái Ngọc Duy, Feb 27, 2012
  11. 05/11 show: use streaming interface for showing blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  12. Junio C HamanoFeb 27, 2012
  13. 06/11 index-pack --verify: skip sha-1 collision testNguyễn Thái Ngọc Duy, Feb 27, 2012
  14. 07/11 index-pack: split second pass obj handling into own functionNguyễn Thái Ngọc Duy, Feb 27, 2012
  15. 08/11 index-pack: reduce memory usage when the pack has large blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  16. 09/11 pack-check: do not unpack blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  17. 10/11 archive: support streaming large files to a tar archiveNguyễn Thái Ngọc Duy, Feb 27, 2012
  18. 11/11 fsck: use streaming interface for writing lost-found blobsNguyễn Thái Ngọc Duy, Feb 27, 2012
  19. Junio C HamanoFeb 27, 2012
  20. Nguyen Thai Ngoc DuyFeb 28, 2012
  21. 00/10 Large blob fixesNguyễn Thái Ngọc Duy, Mar 4, 2012
  22. 01/10 Add more large blob test casesNguyễn Thái Ngọc Duy, Mar 4, 2012
  23. Junio C HamanoMar 6, 2012
  24. 02/10 streaming: make streaming-write-entry to be more reusableNguyễn Thái Ngọc Duy, Mar 4, 2012
  25. 03/10 cat-file: use streaming interface to print blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  26. Junio C HamanoMar 4, 2012
  27. Nguyen Thai Ngoc DuyMar 5, 2012
  28. 04/10 parse_object: special code path for blobs to avoid putting whole object in memoryNguyễn Thái Ngọc Duy, Mar 4, 2012
  29. 05/10 show: use streaming interface for showing blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  30. 06/10 index-pack: split second pass obj handling into own functionNguyễn Thái Ngọc Duy, Mar 4, 2012
  31. 07/10 index-pack: reduce memory usage when the pack has large blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  32. 08/10 pack-check: do not unpack blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  33. 09/10 archive: support streaming large files to a tar archiveNguyễn Thái Ngọc Duy, Mar 4, 2012
  34. 10/10 fsck: use streaming interface for writing lost-found blobsNguyễn Thái Ngọc Duy, Mar 4, 2012
  35. 00/11 Large blob fixesNguyễn Thái Ngọc Duy, Mar 5, 2012
  36. 01/11 Add more large blob test casesNguyễn Thái Ngọc Duy, Mar 5, 2012
  37. 02/11 streaming: make streaming-write-entry to be more reusableNguyễn Thái Ngọc Duy, Mar 5, 2012
  38. 03/11 cat-file: use streaming interface to print blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  39. 04/11 parse_object: special code path for blobs to avoid putting whole object in memoryNguyễn Thái Ngọc Duy, Mar 5, 2012
  40. Junio C HamanoMar 6, 2012
  41. 05/11 show: use streaming interface for showing blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  42. 06/11 index-pack: split second pass obj handling into own functionNguyễn Thái Ngọc Duy, Mar 5, 2012
  43. 07/11 index-pack: reduce memory usage when the pack has large blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  44. 08/11 pack-check: do not unpack blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  45. 09/11 archive: support streaming large files to a tar archiveNguyễn Thái Ngọc Duy, Mar 5, 2012
  46. Junio C HamanoMar 6, 2012
  47. 10/11 fsck: use streaming interface for writing lost-found blobsNguyễn Thái Ngọc Duy, Mar 5, 2012
  48. 11/11 update-server-info: respect core.bigfilethresholdNguyễn Thái Ngọc Duy, Mar 5, 2012

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