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[PATCH 2/4] cat-file: split batch "buf" into two variables

From
Jeff King <peff@peff.net>
Date
Aug 14, 2018, 18:18 UTC
Message-ID
<20180814181806.GB26919@sigill.intra.peff.net>
In-Reply-To
<20180814181358.GA26391@sigill.intra.peff.net>

We use the "buf" strbuf for two things: to read incoming lines, and as a scratch space for test-expanding the user-provided format. Let's split this into two variables with descriptive names, which makes their purpose and lifetime more clear.

It will also help in a future patch when we start using the "output" buffer for more expansions.

Signed-off-by: Jeff King <peff@peff.net>
---
René, in the patch you sent earlier, I noticed that for the
non-batch-all-objects case we use the same strbuf for input and output.
That'd probably be OK most of the time (the first thing we do is resolve
the input to an oid), but I suspect it could be pretty bad with %(rest).
We'd write over or even realloc the string it points into as part of the
output.
This patch just clarifies the names; your reuse idea is in the next one.
 builtin/cat-file.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 04b5cda191..3ed1d0be80 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -466,7 +466,8 @@ static int batch_unordered_packed(const struct object_id *oid,
 
 static int batch_objects(struct batch_options *opt)
 {
-	struct strbuf buf = STRBUF_INIT;
+	struct strbuf input = STRBUF_INIT;
+	struct strbuf output = STRBUF_INIT;
 	struct expand_data data;
 	int save_warning;
 	int retval = 0;
@@ -481,8 +482,9 @@ static int batch_objects(struct batch_options *opt)
 	 */
 	memset(&data, 0, sizeof(data));
 	data.mark_query = 1;
-	strbuf_expand(&buf, opt->format, expand_format, &data);
+	strbuf_expand(&output, opt->format, expand_format, &data);
 	data.mark_query = 0;
+	strbuf_release(&output);
 	if (opt->cmdmode)
 		data.split_on_whitespace = 1;
 
@@ -542,14 +544,14 @@ static int batch_objects(struct batch_options *opt)
 	save_warning = warn_on_object_refname_ambiguity;
 	warn_on_object_refname_ambiguity = 0;
 
-	while (strbuf_getline(&buf, stdin) != EOF) {
+	while (strbuf_getline(&input, stdin) != EOF) {
 		if (data.split_on_whitespace) {
 			/*
 			 * Split at first whitespace, tying off the beginning
 			 * of the string and saving the remainder (or NULL) in
 			 * data.rest.
 			 */
-			char *p = strpbrk(buf.buf, " \t");
+			char *p = strpbrk(input.buf, " \t");
 			if (p) {
 				while (*p && strchr(" \t", *p))
 					*p++ = '\0';
@@ -557,10 +559,10 @@ static int batch_objects(struct batch_options *opt)
 			data.rest = p;
 		}
 
-		batch_one_object(buf.buf, opt, &data);
+		batch_one_object(input.buf, opt, &data);
 	}
 
-	strbuf_release(&buf);
+	strbuf_release(&input);
 	warn_on_object_refname_ambiguity = save_warning;
 	return retval;
 }
-- 
2.18.0.1066.g0d97f3a098
Previous: Jeff KingNext: Jeff King
Message 19 of 27 in “speeding up cat-file by reordering object access”
  1. 0/7 speeding up cat-file by reordering object accessJeff King, Aug 10, 2018
  2. 1/7 for_each_*_object: store flag definitions in a single locationJeff King, Aug 10, 2018
  3. Stefan BellerAug 10, 2018
  4. Jeff KingAug 10, 2018
  5. Jeff KingAug 10, 2018
  6. Stefan BellerAug 10, 2018
  7. Jeff KingAug 11, 2018
  8. 2/7 for_each_*_object: take flag arguments as enumJeff King, Aug 10, 2018
  9. 3/7 for_each_*_object: give more comprehensive docstringsJeff King, Aug 10, 2018
  10. 4/7 for_each_packed_object: support iterating in pack-orderJeff King, Aug 10, 2018
  11. Derrick StoleeAug 15, 2018
  12. Jeff KingAug 16, 2018
  13. 5/7 t1006: test cat-file --batch-all-objects with duplicatesJeff King, Aug 10, 2018
  14. 6/7 cat-file: rename batch_{loose,packed}_object callbacksJeff King, Aug 10, 2018
  15. 7/7 cat-file: support "unordered" output for --batch-all-objectsJeff King, Aug 10, 2018
  16. Jonathan TanAug 13, 2018
  17. 0/4 finishing touches on jk/for-each-object-iterationJeff King, Aug 14, 2018
  18. 1/4 cat-file: use oidset check-and-insertJeff King, Aug 14, 2018
  19. 2/4 cat-file: split batch "buf" into two variablesJeff King, Aug 14, 2018
  20. 3/4 cat-file: use a single strbuf for all outputJeff King, Aug 14, 2018
  21. René ScharfeAug 14, 2018
  22. Jeff KingAug 14, 2018
  23. 4/4 for_each_*_object: move declarations to object-store.hJeff King, Aug 14, 2018
  24. Derrick StoleeAug 15, 2018
  25. Jeff KingAug 16, 2018
  26. Junio C HamanoAug 16, 2018
  27. Jeff KingAug 16, 2018

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