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[PATCH v2 3/7] reftable/refname: refactor binary search over refnames

From
Patrick Steinhardt <ps@pks.im>
Date
Mar 25, 2024, 10:10 UTC
Message-ID
<9ffcf45c32f22245c9978436affcefa914fc6927.1711361340.git.ps@pks.im>
In-Reply-To
<cover.1711361340.git.ps@pks.im>

It is comparatively hard to understand how exactly the binary search over refnames works given that the function and variable names are not exactly easy to grasp. Rename them to make this more obvious. This should not result in any change in behaviour.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
---
 reftable/refname.c | 44 ++++++++++++++++++++++----------------------
 1 file changed, 22 insertions(+), 22 deletions(-)
diff --git a/reftable/refname.c b/reftable/refname.c
index 64eba1b886..9ec488d727 100644
--- a/reftable/refname.c
+++ b/reftable/refname.c
@@ -12,15 +12,15 @@
 #include "refname.h"
 #include "reftable-iterator.h"
 
-struct find_arg {
-	char **names;
-	const char *want;
+struct refname_needle_lesseq_args {
+	char **haystack;
+	const char *needle;
 };
 
-static int find_name(size_t k, void *arg)
+static int refname_needle_lesseq(size_t k, void *arg)
 {
-	struct find_arg *f_arg = arg;
-	return strcmp(f_arg->names[k], f_arg->want) >= 0;
+	struct refname_needle_lesseq_args *f_arg = arg;
+	return strcmp(f_arg->needle, f_arg->haystack[k]) <= 0;
 }
 
 static int modification_has_ref(struct modification *mod, const char *name)
@@ -29,21 +29,21 @@ static int modification_has_ref(struct modification *mod, const char *name)
 	int err = 0;
 
 	if (mod->add_len > 0) {
-		struct find_arg arg = {
-			.names = mod->add,
-			.want = name,
+		struct refname_needle_lesseq_args arg = {
+			.haystack = mod->add,
+			.needle = name,
 		};
-		size_t idx = binsearch(mod->add_len, find_name, &arg);
+		size_t idx = binsearch(mod->add_len, refname_needle_lesseq, &arg);
 		if (idx < mod->add_len && !strcmp(mod->add[idx], name))
 			return 0;
 	}
 
 	if (mod->del_len > 0) {
-		struct find_arg arg = {
-			.names = mod->del,
-			.want = name,
+		struct refname_needle_lesseq_args arg = {
+			.haystack = mod->del,
+			.needle = name,
 		};
-		size_t idx = binsearch(mod->del_len, find_name, &arg);
+		size_t idx = binsearch(mod->del_len, refname_needle_lesseq, &arg);
 		if (idx < mod->del_len && !strcmp(mod->del[idx], name))
 			return 1;
 	}
@@ -71,11 +71,11 @@ static int modification_has_ref_with_prefix(struct modification *mod,
 	int err = 0;
 
 	if (mod->add_len > 0) {
-		struct find_arg arg = {
-			.names = mod->add,
-			.want = prefix,
+		struct refname_needle_lesseq_args arg = {
+			.haystack = mod->add,
+			.needle = prefix,
 		};
-		size_t idx = binsearch(mod->add_len, find_name, &arg);
+		size_t idx = binsearch(mod->add_len, refname_needle_lesseq, &arg);
 		if (idx < mod->add_len &&
 		    !strncmp(prefix, mod->add[idx], strlen(prefix)))
 			goto done;
@@ -90,11 +90,11 @@ static int modification_has_ref_with_prefix(struct modification *mod,
 			goto done;
 
 		if (mod->del_len > 0) {
-			struct find_arg arg = {
-				.names = mod->del,
-				.want = ref.refname,
+			struct refname_needle_lesseq_args arg = {
+				.haystack = mod->del,
+				.needle = ref.refname,
 			};
-			size_t idx = binsearch(mod->del_len, find_name, &arg);
+			size_t idx = binsearch(mod->del_len, refname_needle_lesseq, &arg);
 			if (idx < mod->del_len &&
 			    !strcmp(ref.refname, mod->del[idx]))
 				continue;
-- 
2.44.GIT
Previous: Patrick SteinhardtNext: Justin Tobler
Message 16 of 45 in “reftable: improvements for the `binsearch()` mechanism”
  1. 0/7 reftable: improvements for the `binsearch()` mechanismPatrick Steinhardt, Mar 22, 2024
  2. 1/7 reftable/basics: fix return type of `binsearch()` to be `size_t`Patrick Steinhardt, Mar 22, 2024
  3. 2/7 reftable/basics: improve `binsearch()` testPatrick Steinhardt, Mar 22, 2024
  4. Justin ToblerMar 22, 2024
  5. Patrick SteinhardtMar 25, 2024
  6. 3/7 reftable/refname: refactor binary search over refnamesPatrick Steinhardt, Mar 22, 2024
  7. Justin ToblerMar 22, 2024
  8. Patrick SteinhardtMar 25, 2024
  9. 4/7 reftable/block: refactor binary search over restart pointsPatrick Steinhardt, Mar 22, 2024
  10. 5/7 reftable/block: fix error handling when searching restart pointsPatrick Steinhardt, Mar 22, 2024
  11. 6/7 reftable/record: extract function to decode key lengthsPatrick Steinhardt, Mar 22, 2024
  12. 7/7 reftable/block: avoid decoding keys when searching restart pointsPatrick Steinhardt, Mar 22, 2024
  13. 0/7 reftable: improvements for the `binsearch()` mechanismPatrick Steinhardt, Mar 25, 2024
  14. 1/7 reftable/basics: fix return type of `binsearch()` to be `size_t`Patrick Steinhardt, Mar 25, 2024
  15. 2/7 reftable/basics: improve `binsearch()` testPatrick Steinhardt, Mar 25, 2024
  16. 3/7 reftable/refname: refactor binary search over refnamesPatrick Steinhardt, Mar 25, 2024
  17. Justin ToblerApr 2, 2024
  18. Patrick SteinhardtApr 2, 2024
  19. 4/7 reftable/block: refactor binary search over restart pointsPatrick Steinhardt, Mar 25, 2024
  20. Justin ToblerApr 2, 2024
  21. Patrick SteinhardtApr 2, 2024
  22. Justin ToblerApr 2, 2024
  23. Patrick SteinhardtApr 3, 2024
  24. 5/7 reftable/block: fix error handling when searching restart pointsPatrick Steinhardt, Mar 25, 2024
  25. 6/7 reftable/record: extract function to decode key lengthsPatrick Steinhardt, Mar 25, 2024
  26. 7/7 reftable/block: avoid decoding keys when searching restart pointsPatrick Steinhardt, Mar 25, 2024
  27. Justin ToblerApr 2, 2024
  28. Patrick SteinhardtApr 2, 2024
  29. 0/7 reftable: improvements for the `binsearch()` mechanismPatrick Steinhardt, Apr 2, 2024
  30. 1/7 reftable/basics: fix return type of `binsearch()` to be `size_t`Patrick Steinhardt, Apr 2, 2024
  31. 2/7 reftable/basics: improve `binsearch()` testPatrick Steinhardt, Apr 2, 2024
  32. 3/7 reftable/refname: refactor binary search over refnamesPatrick Steinhardt, Apr 2, 2024
  33. 4/7 reftable/block: refactor binary search over restart pointsPatrick Steinhardt, Apr 2, 2024
  34. 5/7 reftable/block: fix error handling when searching restart pointsPatrick Steinhardt, Apr 2, 2024
  35. 6/7 reftable/record: extract function to decode key lengthsPatrick Steinhardt, Apr 2, 2024
  36. 7/7 reftable/block: avoid decoding keys when searching restart pointsPatrick Steinhardt, Apr 2, 2024
  37. Justin ToblerApr 2, 2024
  38. 0/7 reftable: improvements for the `binsearch()` mechanismPatrick Steinhardt, Apr 3, 2024
  39. 1/7 reftable/basics: fix return type of `binsearch()` to be `size_t`Patrick Steinhardt, Apr 3, 2024
  40. 2/7 reftable/basics: improve `binsearch()` testPatrick Steinhardt, Apr 3, 2024
  41. 3/7 reftable/refname: refactor binary search over refnamesPatrick Steinhardt, Apr 3, 2024
  42. 4/7 reftable/block: refactor binary search over restart pointsPatrick Steinhardt, Apr 3, 2024
  43. 5/7 reftable/block: fix error handling when searching restart pointsPatrick Steinhardt, Apr 3, 2024
  44. 6/7 reftable/record: extract function to decode key lengthsPatrick Steinhardt, Apr 3, 2024
  45. 7/7 reftable/block: avoid decoding keys when searching restart pointsPatrick Steinhardt, Apr 3, 2024

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