Merge pull request #2308 from libgit2/rb/diff-update-index-stat-cache

Reduce excessive OID calculation for diff and stat

4 files changed, 40 insertions, 15 deletions

diff --git a/include/git2/sys/config.h b/include/git2/sys/config.h
index 3df2ba327..46bb65293 100644
--- a/include/git2/sys/config.h
+++ b/include/git2/sys/config.h
@@ -73,14 +73,13 @@ struct git_config_backend {
  * Initializes a `git_config_backend` with default values. Equivalent to
  * creating an instance with GIT_CONFIG_BACKEND_INIT.
  *
- * @param opts the `git_config_backend` instance to initialize.
- * @param version the version of the struct; you should pass
- *        `GIT_CONFIG_BACKEND_VERSION` here.
+ * @param opts the `git_config_backend` struct to initialize.
+ * @param version Version of struct; pass `GIT_CONFIG_BACKEND_VERSION`
  * @return Zero on success; -1 on failure.
  */
 GIT_EXTERN(int) git_config_init_backend(
-	git_config_backend* backend,
-	int version);
+	git_config_backend *backend,
+	unsigned int version);
 
 /**
  * Add a generic config file instance to an existing config
diff --git a/include/git2/sys/diff.h b/include/git2/sys/diff.h
index bc6cdf393..48d72f4f9 100644
--- a/include/git2/sys/diff.h
+++ b/include/git2/sys/diff.h
@@ -10,6 +10,8 @@
 #include "git2/common.h"
 #include "git2/types.h"
 #include "git2/oid.h"
+#include "git2/diff.h"
+#include "git2/status.h"
 
 /**
  * @file git2/sys/diff.h
@@ -58,6 +60,32 @@ GIT_EXTERN(int) git_diff_print_callback__to_file_handle(
 	const git_diff_line *line,
 	void *payload); /*< payload must be a `FILE *` */
 
+
+typedef struct {
+	unsigned int version;
+	size_t stat_calls;
+	size_t oid_calculations;
+} git_diff_perfdata;
+
+#define GIT_DIFF_PERFDATA_VERSION 1
+#define GIT_DIFF_PERFDATA_INIT {GIT_DIFF_PERFDATA_VERSION,0,0}
+
+/**
+ * Get performance data for a diff object.
+ *
+ * @param out Structure to be filled with diff performance data
+ * @param diff Diff to read performance data from
+ * @return 0 for success, <0 for error
+ */
+GIT_EXTERN(int) git_diff_get_perfdata(
+	git_diff_perfdata *out, const git_diff *diff);
+
+/**
+ * Get performance data for diffs from a git_status_list
+ */
+GIT_EXTERN(int) git_status_list_get_perfdata(
+	git_diff_perfdata *out, const git_status_list *status);
+
 /** @} */
 GIT_END_DECL
 #endif
diff --git a/include/git2/sys/odb_backend.h b/include/git2/sys/odb_backend.h
index 77fe0dd31..1fc3c3159 100644
--- a/include/git2/sys/odb_backend.h
+++ b/include/git2/sys/odb_backend.h
@@ -93,14 +93,13 @@ struct git_odb_backend {
  * Initializes a `git_odb_backend` with default values. Equivalent to
  * creating an instance with GIT_ODB_BACKEND_INIT.
  *
- * @param opts the `git_odb_backend` instance to initialize.
- * @param version the version of the struct; you should pass
- *        `GIT_ODB_BACKEND_VERSION` here.
+ * @param opts the `git_odb_backend` struct to initialize.
+ * @param version Version the struct; pass `GIT_ODB_BACKEND_VERSION`
  * @return Zero on success; -1 on failure.
  */
 GIT_EXTERN(int) git_odb_init_backend(
-	git_odb_backend* backend,
-	int version);
+	git_odb_backend *backend,
+	unsigned int version);
 
 GIT_EXTERN(void *) git_odb_backend_malloc(git_odb_backend *backend, size_t len);
 
diff --git a/include/git2/sys/refdb_backend.h b/include/git2/sys/refdb_backend.h
index dce142c77..3b216a287 100644
--- a/include/git2/sys/refdb_backend.h
+++ b/include/git2/sys/refdb_backend.h
@@ -162,14 +162,13 @@ struct git_refdb_backend {
  * Initializes a `git_refdb_backend` with default values. Equivalent to
  * creating an instance with GIT_REFDB_BACKEND_INIT.
  *
- * @param opts the `git_refdb_backend` instance to initialize.
- * @param version the version of the struct; you should pass
- *        `GIT_REFDB_BACKEND_VERSION` here.
+ * @param opts the `git_refdb_backend` struct to initialize
+ * @param version Version of struct; pass `GIT_REFDB_BACKEND_VERSION`
  * @return Zero on success; -1 on failure.
  */
 GIT_EXTERN(int) git_refdb_init_backend(
-	git_refdb_backend* backend,
-	int version);
+	git_refdb_backend *backend,
+	unsigned int version);
 
 /**
  * Constructors for default filesystem-based refdb backend