replace-objects: create wrapper around setting

The 'read_replace_objects' constant is initialized by git_default_config
(if core.useReplaceRefs is disabled) and within setup_git_env (if
GIT_NO_REPLACE_OBJECTS) is set. To ensure that this variable cannot be
set accidentally in other places, wrap it in a replace_refs_enabled()
method.

Since we still assign this global in config.c, we are not able to remove
the global scope of this variable and make it a static within
replace-object.c. This will happen in a later change which will also
prevent the variable from being read before it is initialized.

Centralizing read access to the variable is an important first step.

Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/commit-graph.c b/commit-graph.c
index 43558b4d9b0230a6d8c759691ddfa55801faf328..95873317bf78dd8876f9554344c780474fccebc1 100644 (file)
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -203,14 +203,12 @@ static struct commit_graph *alloc_commit_graph(void)
        return g;
 }
 
-extern int read_replace_refs;
-
 static int commit_graph_compatible(struct repository *r)
 {
        if (!r->gitdir)
                return 0;
 
-       if (read_replace_refs) {
+       if (replace_refs_enabled(r)) {
                prepare_replace_object(r);
                if (hashmap_get_size(&r->objects->replace_map->map))
                        return 0;

diff --git a/log-tree.c b/log-tree.c
index 143b86fecf9cc94d540055003271e3af694a9332..86212af36269738f18ec5b1299b0e3c09f9e30b3 100644 (file)
--- a/log-tree.c
+++ b/log-tree.c
@@ -155,7 +155,7 @@ static int add_ref_decoration(const char *refname, const struct object_id *oid,
 
        if (starts_with(refname, git_replace_ref_base)) {
                struct object_id original_oid;
-               if (!read_replace_refs)
+               if (!replace_refs_enabled(the_repository))
                        return 0;
                if (get_oid_hex(refname + strlen(git_replace_ref_base),
                                &original_oid)) {

diff --git a/replace-object.c b/replace-object.c
index ceec81c940ceffd8339b1d8e7a3c4f800d49301c..07cfedd6df478aead3f56d6b23489839767b62b2 100644 (file)
--- a/replace-object.c
+++ b/replace-object.c
@@ -89,3 +89,8 @@ void disable_replace_refs(void)
 {
        read_replace_refs = 0;
 }
+
+int replace_refs_enabled(struct repository *r)
+{
+       return read_replace_refs;
+}

diff --git a/replace-object.h b/replace-object.h
index 7786d4152b053767ce633e94e0b003cd1d6626f5..3e9c3516c3cf6829e0b9f1ea1955589f421f2145 100644 (file)
--- a/replace-object.h
+++ b/replace-object.h
@@ -27,6 +27,18 @@ void prepare_replace_object(struct repository *r);
 const struct object_id *do_lookup_replace_object(struct repository *r,
                                                 const struct object_id *oid);
 
+/*
+ * Some commands disable replace-refs unconditionally, and otherwise each
+ * repository could alter the core.useReplaceRefs config value.
+ *
+ * Return 1 if and only if all of the following are true:
+ *
+ *  a. disable_replace_refs() has not been called.
+ *  b. GIT_NO_REPLACE_OBJECTS is unset or zero.
+ *  c. the given repository does not have core.useReplaceRefs=false.
+ */
+int replace_refs_enabled(struct repository *r);
+
 /*
  * If object sha1 should be replaced, return the replacement object's
  * name (replaced recursively, if necessary).  The return value is
@@ -41,7 +53,7 @@ const struct object_id *do_lookup_replace_object(struct repository *r,
 static inline const struct object_id *lookup_replace_object(struct repository *r,
                                                            const struct object_id *oid)
 {
-       if (!read_replace_refs ||
+       if (!replace_refs_enabled(r) ||
            (r->objects->replace_map_initialized &&
             r->objects->replace_map->map.tablesize == 0))
                return oid;