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[PATCH v3 2/5] fetch: use strbuf to format FETCH_HEAD updates

From
Patrick Steinhardt <ps@pks.im>
Date
Jan 11, 2021, 11:05 UTC
Message-ID
<a19762690eb7f9957ac31d73e110f0103aeb2307.1610362744.git.ps@pks.im>
In-Reply-To
<cover.1610362744.git.ps@pks.im>

This commit refactors `append_fetch_head()` to use a `struct strbuf` for formatting the update which we're about to append to the FETCH_HEAD file. While the refactoring doesn't have much of a benefit right now, it servers as a preparatory step to implement atomic fetches where we need to buffer all updates to FETCH_HEAD and only flush them out if all reference updates succeeded.

No change in behaviour is expected from this commit.
---
 builtin/fetch.c | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/builtin/fetch.c b/builtin/fetch.c
index 50f0306a92..1252f37493 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -899,6 +899,7 @@ static int iterate_ref_map(void *cb_data, struct object_id *oid)
 
 struct fetch_head {
 	FILE *fp;
+	struct strbuf buf;
 };
 
 static int open_fetch_head(struct fetch_head *fetch_head)
@@ -909,6 +910,7 @@ static int open_fetch_head(struct fetch_head *fetch_head)
 		fetch_head->fp = fopen(filename, "a");
 		if (!fetch_head->fp)
 			return error_errno(_("cannot open %s"), filename);
+		strbuf_init(&fetch_head->buf, 0);
 	} else {
 		fetch_head->fp = NULL;
 	}
@@ -941,14 +943,17 @@ static void append_fetch_head(struct fetch_head *fetch_head,
 			return;
 	}
 
-	fprintf(fetch_head->fp, "%s\t%s\t%s",
-		oid_to_hex_r(old_oid_hex, old_oid), merge_status_marker, note);
+	strbuf_addf(&fetch_head->buf, "%s\t%s\t%s",
+		    oid_to_hex_r(old_oid_hex, old_oid), merge_status_marker, note);
 	for (i = 0; i < url_len; ++i)
 		if ('\n' == url[i])
-			fputs("\\n", fetch_head->fp);
+			strbuf_addstr(&fetch_head->buf, "\\n");
 		else
-			fputc(url[i], fetch_head->fp);
-	fputc('\n', fetch_head->fp);
+			strbuf_addch(&fetch_head->buf, url[i]);
+	strbuf_addch(&fetch_head->buf, '\n');
+
+	strbuf_write(&fetch_head->buf, fetch_head->fp);
+	strbuf_reset(&fetch_head->buf);
 }
 
 static void commit_fetch_head(struct fetch_head *fetch_head)
@@ -962,6 +967,7 @@ static void close_fetch_head(struct fetch_head *fetch_head)
 		return;
 
 	fclose(fetch_head->fp);
+	strbuf_release(&fetch_head->buf);
 }
 
 static const char warn_show_forced_updates[] =
-- 
2.30.0
Previous: Junio C HamanoNext: Patrick Steinhardt
Message 28 of 41 in “fetch: implement support for atomic reference updates”
  1. 0/2 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 7, 2021
  2. 1/2 fetch: allow passing a transaction to `s_update_ref()`Patrick Steinhardt, Jan 7, 2021
  3. Junio C HamanoJan 7, 2021
  4. Christian CouderJan 8, 2021
  5. Junio C HamanoJan 8, 2021
  6. 2/2 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 7, 2021
  7. Junio C HamanoJan 8, 2021
  8. 0/4 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 8, 2021
  9. 1/4 fetch: extract writing to FETCH_HEADPatrick Steinhardt, Jan 8, 2021
  10. Junio C HamanoJan 8, 2021
  11. Patrick SteinhardtJan 11, 2021
  12. Junio C HamanoJan 11, 2021
  13. 3/4 fetch: allow passing a transaction to `s_update_ref()`Patrick Steinhardt, Jan 8, 2021
  14. Junio C HamanoJan 8, 2021
  15. 2/4 fetch: refactor `s_update_ref` to use common exit pathPatrick Steinhardt, Jan 8, 2021
  16. Junio C HamanoJan 8, 2021
  17. Patrick SteinhardtJan 11, 2021
  18. 4/4 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 8, 2021
  19. Junio C HamanoJan 9, 2021
  20. Patrick SteinhardtJan 11, 2021
  21. Junio C HamanoJan 11, 2021
  22. Patrick SteinhardtJan 12, 2021
  23. Patrick SteinhardtJan 12, 2021
  24. Junio C HamanoJan 12, 2021
  25. 0/5 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 11, 2021
  26. 1/5 fetch: extract writing to FETCH_HEADPatrick Steinhardt, Jan 11, 2021
  27. Junio C HamanoJan 11, 2021
  28. 2/5 fetch: use strbuf to format FETCH_HEAD updatesPatrick Steinhardt, Jan 11, 2021
  29. Patrick SteinhardtJan 11, 2021
  30. Christian CouderJan 11, 2021
  31. Junio C HamanoJan 11, 2021
  32. 4/5 fetch: allow passing a transaction to `s_update_ref()`Patrick Steinhardt, Jan 11, 2021
  33. 3/5 fetch: refactor `s_update_ref` to use common exit pathPatrick Steinhardt, Jan 11, 2021
  34. 5/5 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 11, 2021
  35. Junio C HamanoJan 12, 2021
  36. 0/5 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 12, 2021
  37. 3/5 fetch: refactor `s_update_ref` to use common exit pathPatrick Steinhardt, Jan 12, 2021
  38. 1/5 fetch: extract writing to FETCH_HEADPatrick Steinhardt, Jan 12, 2021
  39. 2/5 fetch: use strbuf to format FETCH_HEAD updatesPatrick Steinhardt, Jan 12, 2021
  40. 4/5 fetch: allow passing a transaction to `s_update_ref()`Patrick Steinhardt, Jan 12, 2021
  41. 5/5 fetch: implement support for atomic reference updatesPatrick Steinhardt, Jan 12, 2021

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