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[PATCH 1/7] streaming: make streaming-write-entry to be more reusable

From
Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Date
Mar 7, 2012, 10:54 UTC
Message-ID
<1331117661-19378-2-git-send-email-pclouds@gmail.com>
In-Reply-To
<1331117661-19378-1-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: 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: Nguyễn Thái Ngọc DuyNext: Nguyễn Thái Ngọc Duy
Message 5 of 13 in “What's cooking in git.git (Mar 2012, #03; Mon, 5)”
  1. Junio C HamanoMar 6, 2012
  2. Nguyen Thai Ngoc DuyMar 6, 2012
  3. Junio C HamanoMar 6, 2012
  4. 0/7 nd/stream-more updatesNguyễn Thái Ngọc Duy, Mar 7, 2012
  5. 1/7 streaming: make streaming-write-entry to be more reusableNguyễn Thái Ngọc Duy, Mar 7, 2012
  6. 2/7 Add more large blob test casesNguyễn Thái Ngọc Duy, Mar 7, 2012
  7. 3/7 cat-file: use streaming API to print blobsNguyễn Thái Ngọc Duy, Mar 7, 2012
  8. 4/7 parse_object: avoid putting whole blob in coreNguyễn Thái Ngọc Duy, Mar 7, 2012
  9. 5/7 show: use streaming API for showing blobsNguyễn Thái Ngọc Duy, Mar 7, 2012
  10. 6/7 fsck: use streaming API for writing lost-found blobsNguyễn Thái Ngọc Duy, Mar 7, 2012
  11. 7/7 update-server-info: respect core.bigfilethresholdNguyễn Thái Ngọc Duy, Mar 7, 2012
  12. Junio C HamanoMar 7, 2012
  13. In preparation for 1.7.10-rc0Junio C Hamano, Mar 7, 2012

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