[PATCH 1/3] rev-list --bisect: Move finding bisection into do_find_bisection.

[PATCH 1/3] rev-list --bisect: Move finding bisection into do_find_bisection.

[Christian Couder]

This factorises some code and make a big function smaller.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
---
 builtin-rev-list.c |   40 +++++++++++++++++++++++++---------------
 1 files changed, 25 insertions(+), 15 deletions(-)

diff --git a/builtin-rev-list.c b/builtin-rev-list.c
index ac551d5..f32c712 100644
--- a/builtin-rev-list.c
+++ b/builtin-rev-list.c
@@ -255,6 +255,9 @@ static void show_list(const char *debug, int counted, int nr,
 }
 #endif /* DEBUG_BISECT */
 
+static struct commit_list *do_find_bisection(struct commit_list *list,
+					     int nr, int *weights);
+
 /*
  * zero or positive weight is the number of interesting commits it can
  * reach, including itself.  Especially, weight = 0 means it does not
@@ -272,7 +275,7 @@ static void show_list(const char *debug, int counted, int nr,
 static struct commit_list *find_bisection(struct commit_list *list,
 					  int *reaches, int *all)
 {
-	int n, nr, on_list, counted, distance;
+	int nr, on_list;
 	struct commit_list *p, *best, *next, *last;
 	int *weights;
 
@@ -301,6 +304,25 @@ static struct commit_list *find_bisection(struct commit_list *list,
 
 	*all = nr;
 	weights = xcalloc(on_list, sizeof(*weights));
+
+	/* Do the real work of finding bisection commit. */
+	best = do_find_bisection(list, nr, weights);
+
+	if (best)
+		best->next = NULL;
+
+	*reaches = weight(best);
+	free(weights);
+
+	return best;
+}
+
+static struct commit_list *do_find_bisection(struct commit_list *list,
+					     int nr, int *weights)
+{
+	int n, counted, distance;
+	struct commit_list *p, *best;
+
 	counted = 0;
 
 	for (n = 0, p = list; p; p = p->next) {
@@ -357,12 +379,8 @@ static struct commit_list *find_bisection(struct commit_list *list,
 		weight_set(p, distance);
 
 		/* Does it happen to be at exactly half-way? */
-		if (halfway(p, distance, nr)) {
-			p->next = NULL;
-			*reaches = distance;
-			free(weights);
+		if (halfway(p, distance, nr))
 			return p;
-		}
 		counted++;
 	}
 
@@ -400,12 +418,8 @@ static struct commit_list *find_bisection(struct commit_list *list,
 
 			/* Does it happen to be at exactly half-way? */
 			distance = weight(p);
-			if (halfway(p, distance, nr)) {
-				p->next = NULL;
-				*reaches = distance;
-				free(weights);
+			if (halfway(p, distance, nr))
 				return p;
-			}
 		}
 	}
 
@@ -425,12 +439,8 @@ static struct commit_list *find_bisection(struct commit_list *list,
 		if (distance > counted) {
 			best = p;
 			counted = distance;
-			*reaches = weight(p);
 		}
 	}
-	if (best)
-		best->next = NULL;
-	free(weights);
 	return best;
 }
 
-- 
1.5.3.1.20.g2a16-dirty

Re: [PATCH 1/3] rev-list --bisect: Move finding bisection into do_find_bisection.

[Junio C Hamano]

Christian Couder <chriscool@tuxfamily.org> writes:

> This factorises some code and make a big function smaller.

I think the refactoring itself makes sense, especially where it
simplifies the clean-up of weight array in early-return
codepath.  But I have a couple of comments, though.

> +static struct commit_list *do_find_bisection(struct commit_list *list,
> +					     int nr, int *weights);
> +
>  /*
>   * zero or positive weight is the number of interesting commits it can
>   * reach, including itself.  Especially, weight = 0 means it does not

The comment whose top part we can see here talks about the magic
values -1 and -2 used while do_find_bisection() after the
refactoring does its work, and these magic values are never
visible to the calling function.  You should move the comment to
the top of do_find_bisection() as well.

Also this forward declaration is unwarranted.  A bottom-up
sequence to define do_find_bisection() first, then to define its
sole caller find_bisection() next is easier to read at least for
me.

The latter comment also applies to your other patch.

Re: [PATCH 1/3] rev-list --bisect: Move finding bisection into do_find_bisection.

[Christian Couder]

Le dimanche 16 septembre 2007, Junio C Hamano a écrit :
> > +static struct commit_list *do_find_bisection(struct commit_list *list,
> > +					     int nr, int *weights);
> > +
> >  /*
> >   * zero or positive weight is the number of interesting commits it can
> >   * reach, including itself.  Especially, weight = 0 means it does not
>
> The comment whose top part we can see here talks about the magic
> values -1 and -2 used while do_find_bisection() after the
> refactoring does its work, and these magic values are never
> visible to the calling function.  You should move the comment to
> the top of do_find_bisection() as well.
>
> Also this forward declaration is unwarranted.  A bottom-up
> sequence to define do_find_bisection() first, then to define its
> sole caller find_bisection() next is easier to read at least for
> me.
>
> The latter comment also applies to your other patch.

All right, I will send new patchs with these changes.

Thanks,
Christian.

[PATCH 1/3] rev-list --bisect: Move finding bisection into do_find_bisection.

[Christian Couder]

This factorises some code and make a big function smaller.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
---
 builtin-rev-list.c |   90 +++++++++++++++++++++++++++------------------------
 1 files changed, 48 insertions(+), 42 deletions(-)

	This patch series is a resend with the changes Junio asked for. 

diff --git a/builtin-rev-list.c b/builtin-rev-list.c
index ac551d5..2dae287 100644
--- a/builtin-rev-list.c
+++ b/builtin-rev-list.c
@@ -268,39 +268,12 @@ static void show_list(const char *debug, int counted, int nr,
  * unknown.  After running count_distance() first, they will get zero
  * or positive distance.
  */
-
-static struct commit_list *find_bisection(struct commit_list *list,
-					  int *reaches, int *all)
+static struct commit_list *do_find_bisection(struct commit_list *list,
+					     int nr, int *weights)
 {
-	int n, nr, on_list, counted, distance;
-	struct commit_list *p, *best, *next, *last;
-	int *weights;
-
-	show_list("bisection 2 entry", 0, 0, list);
-
-	/*
-	 * Count the number of total and tree-changing items on the
-	 * list, while reversing the list.
-	 */
-	for (nr = on_list = 0, last = NULL, p = list;
-	     p;
-	     p = next) {
-		unsigned flags = p->item->object.flags;
+	int n, counted, distance;
+	struct commit_list *p, *best;
 
-		next = p->next;
-		if (flags & UNINTERESTING)
-			continue;
-		p->next = last;
-		last = p;
-		if (!revs.prune_fn || (flags & TREECHANGE))
-			nr++;
-		on_list++;
-	}
-	list = last;
-	show_list("bisection 2 sorted", 0, nr, list);
-
-	*all = nr;
-	weights = xcalloc(on_list, sizeof(*weights));
 	counted = 0;
 
 	for (n = 0, p = list; p; p = p->next) {
@@ -357,12 +330,8 @@ static struct commit_list *find_bisection(struct commit_list *list,
 		weight_set(p, distance);
 
 		/* Does it happen to be at exactly half-way? */
-		if (halfway(p, distance, nr)) {
-			p->next = NULL;
-			*reaches = distance;
-			free(weights);
+		if (halfway(p, distance, nr))
 			return p;
-		}
 		counted++;
 	}
 
@@ -400,12 +369,8 @@ static struct commit_list *find_bisection(struct commit_list *list,
 
 			/* Does it happen to be at exactly half-way? */
 			distance = weight(p);
-			if (halfway(p, distance, nr)) {
-				p->next = NULL;
-				*reaches = distance;
-				free(weights);
+			if (halfway(p, distance, nr))
 				return p;
-			}
 		}
 	}
 
@@ -425,12 +390,53 @@ static struct commit_list *find_bisection(struct commit_list *list,
 		if (distance > counted) {
 			best = p;
 			counted = distance;
-			*reaches = weight(p);
 		}
 	}
+	return best;
+}
+
+static struct commit_list *find_bisection(struct commit_list *list,
+					  int *reaches, int *all)
+{
+	int nr, on_list;
+	struct commit_list *p, *best, *next, *last;
+	int *weights;
+
+	show_list("bisection 2 entry", 0, 0, list);
+
+	/*
+	 * Count the number of total and tree-changing items on the
+	 * list, while reversing the list.
+	 */
+	for (nr = on_list = 0, last = NULL, p = list;
+	     p;
+	     p = next) {
+		unsigned flags = p->item->object.flags;
+
+		next = p->next;
+		if (flags & UNINTERESTING)
+			continue;
+		p->next = last;
+		last = p;
+		if (!revs.prune_fn || (flags & TREECHANGE))
+			nr++;
+		on_list++;
+	}
+	list = last;
+	show_list("bisection 2 sorted", 0, nr, list);
+
+	*all = nr;
+	weights = xcalloc(on_list, sizeof(*weights));
+
+	/* Do the real work of finding bisection commit. */
+	best = do_find_bisection(list, nr, weights);
+
 	if (best)
 		best->next = NULL;
+
+	*reaches = weight(best);
 	free(weights);
+
 	return best;
 }
 
-- 
1.5.3.1.59.g93705