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[PATCH 1/3] fast-import: extract object preparation function

From
Dmitry Ivankov <divanorama@gmail.com>
Date
Aug 12, 2011, 10:32 UTC
Message-ID
<1313145170-24471-2-git-send-email-divanorama@gmail.com>
In-Reply-To
<1313145170-24471-1-git-send-email-divanorama@gmail.com>

We're constructing raw objects and compute their sha1's in fast-import just before saving them.

Extract header and sha1 computations so that we can get sha1 without actually saving the object.

Signed-off-by: Dmitry Ivankov <divanorama@gmail.com>
---
 fast-import.c |   32 +++++++++++++++++++++++++-------
 1 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/fast-import.c b/fast-import.c
index 7cc2262..d0f8580 100644
--- a/fast-import.c
+++ b/fast-import.c
@@ -1006,6 +1006,30 @@ static void cycle_packfile(void)
 	start_packfile();
 }
 
+static void prepare_object_hash(
+	enum object_type type,
+	struct strbuf *dat,
+	unsigned char *hdr_out,
+	unsigned long *hdrlen_out,
+	unsigned char *sha1_out
+)
+{
+	unsigned char hdr_[96];
+	unsigned char *hdr = hdr_out ? hdr_out : hdr_;
+	unsigned long hdrlen;
+	git_SHA_CTX c;
+
+	hdrlen = sprintf((char *)hdr,"%s %lu", typename(type),
+		(unsigned long)dat->len) + 1;
+	git_SHA1_Init(&c);
+	git_SHA1_Update(&c, hdr, hdrlen);
+	git_SHA1_Update(&c, dat->buf, dat->len);
+	git_SHA1_Final(sha1_out, &c);
+
+	if (hdrlen_out)
+		*hdrlen_out = hdrlen;
+}
+
 static int store_object(
 	enum object_type type,
 	struct strbuf *dat,
@@ -1018,15 +1042,9 @@ static int store_object(
 	unsigned char hdr[96];
 	unsigned char sha1[20];
 	unsigned long hdrlen, deltalen;
-	git_SHA_CTX c;
 	git_zstream s;
 
-	hdrlen = sprintf((char *)hdr,"%s %lu", typename(type),
-		(unsigned long)dat->len) + 1;
-	git_SHA1_Init(&c);
-	git_SHA1_Update(&c, hdr, hdrlen);
-	git_SHA1_Update(&c, dat->buf, dat->len);
-	git_SHA1_Final(sha1, &c);
+	prepare_object_hash(type, dat, hdr, &hdrlen, sha1);
 	if (sha1out)
 		hashcpy(sha1out, sha1);
 
-- 
1.7.3.4
Previous: Dmitry IvankovNext: Dmitry Ivankov
Message 2 of 14 in “fix data corruption in fast-import”
  1. 0/3 fix data corruption in fast-importDmitry Ivankov, Aug 12, 2011
  2. 1/3 fast-import: extract object preparation functionDmitry Ivankov, Aug 12, 2011
  3. 2/3 fast-import: add a check for tree delta base sha1Dmitry Ivankov, Aug 12, 2011
  4. Jonathan NiederAug 13, 2011
  5. 3/3 fast-import: prevent producing bad deltaDmitry Ivankov, Aug 12, 2011
  6. 0/2 fix data corruption in fast-importDmitry Ivankov, Aug 14, 2011
  7. 1/2 fast-import: add a test for tree delta base corruptionDmitry Ivankov, Aug 14, 2011
  8. 2/2 fast-import: prevent producing bad deltaDmitry Ivankov, Aug 14, 2011
  9. fast-import: do not write bad delta for replaced subtreesJonathan Nieder, Aug 20, 2011
  10. Andreas SchwabAug 20, 2011
  11. Jonathan NiederAug 20, 2011
  12. fast-import: do not write bad delta for replaced subtreesDmitry Ivankov, Aug 20, 2011
  13. Jonathan NiederAug 20, 2011
  14. Dmitry IvankovAug 20, 2011

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