On 8/21/2018 1:45 PM, Junio C Hamano wrote:
Derrick Stolee <dsto...@microsoft.com> writes:
Create new method commit_graph_compatible(r) to check if a given
repository r is compatible with the commit-graph feature. Fill the
method with a check to see if replace-objects exist. Test this
interaction succeeds, including ignoring an existing commit-graph and
failing to write a new commit-graph. However, we do ensure that
we write a new commit-graph by setting read_replace_refs to 0, thereby
ignoring the replace refs.
Signed-off-by: Derrick Stolee <dsto...@microsoft.com>
---
builtin/commit-graph.c | 4 ++++
commit-graph.c | 21 +++++++++++++++++++++
replace-object.c | 2 +-
replace-object.h | 2 ++
t/t5318-commit-graph.sh | 22 ++++++++++++++++++++++
5 files changed, 50 insertions(+), 1 deletion(-)
diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 0bf0c48657..da737df321 100644
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -120,6 +120,8 @@ static int graph_read(int argc, const char **argv)
return 0;
}
+extern int read_replace_refs;
+
Why do you need this (and also in commit-graph.c)? I thought
cache.h includes it, which you can just make use of it.
You're right. I don't know how I missed that.
+static int commit_graph_compatible(struct repository *r)
+{
+ if (read_replace_refs) {
+ prepare_replace_object(r);
+ if (hashmap_get_size(&r->objects->replace_map->map))
+ return 0;
+ }
+
+ return 1;
+}
diff --git a/replace-object.c b/replace-object.c
index 3c17864eb7..9821f1477e 100644
--- a/replace-object.c
+++ b/replace-object.c
@@ -32,7 +32,7 @@ static int register_replace_ref(struct repository *r,
return 0;
}
-static void prepare_replace_object(struct repository *r)
+void prepare_replace_object(struct repository *r)
{
if (r->objects->replace_map)
return;
The way the new caller is written, I am wondering if this function
should return "we are (or, are not) using the replace object
feature", making it unnecessary for callers on the reading side to
know about "read-replace-refs" external variable, for example.
/*
* To be called on-demand from codepaths that want to make
* sure that replacement objects can be found as necessary.
*
* Return number of replacement defined for the repository, or
* -1 when !read_replace_refs tells us not to use replacement
* mechanism at all.
*/
int prepare_replace_object(struct repository *r)
{
if (!read_replace_refs)
return -1;
if (!r->objects->replace_map) {
r->objects->replace_map =
xmalloc(...);
oidmap_init(r->objects->replace_map, 0);
for_each_refplace_ref(r, register_...);
}
return hashmap_get_size(&r->objects->replace_map->map);
}
This is a good idea. I can incorporate it into v3.
Then, the caller side can simply become something like:
#define cgraph_compat(r) (prepare_replace_object(r) <= 0)
With the next two patches that add more conditions to
commit_graph_compatible(), I'd prefer keeping it a method instead of a
macro.
There are various writers to read_replace_refs variable, but I think
they should first be replaced with calls to something like:
void use_replace_refs(struct repository *r, int enable);
which allows us to hide the global variable and later make it per
repository if we wanted to.
I will incorporate this into v3 as well.
Thanks,
-Stolee
