Don't expose the fetch code to the user

Move the generation of the want-list to be done from the negotiate
function, and keep the filtered references inside the remote
structure.

Signed-off-by: Carlos Martín Nieto <carlos@cmartin.tk>

include/git2/remote.h

@@ -91,9 +91,12 @@ GIT_EXTERN(const git_refspec *) git_remote_pushspec(struct git_remote *remote);
 /**
  * Open a connection to a remote
  *
- * The transport is selected based on the URL
+ * The transport is selected based on the URL. The direction argument
+ * is due to a limitation of the git protocol (over TCP or SSH) which
+ * starts up a specific binary which can only do the one or the other.
  *
  * @param remote the remote to connect to
+ * @param direction whether you want to receive or send data
  * @return GIT_SUCCESS or an error code
  */
 GIT_EXTERN(int) git_remote_connect(struct git_remote *remote, int direction);
@@ -109,6 +112,14 @@ GIT_EXTERN(int) git_remote_connect(struct git_remote *remote, int direction);
  */
 GIT_EXTERN(int) git_remote_ls(git_remote *remote, git_headarray *refs);
 
+/**
+ * Negotiate what data needs to be exchanged to synchroize the remtoe
+ * and local references
+ *
+ * @param remote the remote you want to negotiate with
+ */
+GIT_EXTERN(int) git_remote_negotiate(git_remote *remote);
+
 /**
  * Free the memory associated with a remote
  *

src/fetch.c

@@ -32,6 +32,7 @@
 #include "transport.h"
 #include "remote.h"
 #include "refspec.h"
+#include "fetch.h"
 
 /*
  * Don't forget that this depends on the enum being correctly set
@@ -44,11 +45,7 @@ static int whn_cmp(const void *a, const void *b)
 	return headb->type - heada->type;
 }
 
-/*
- * FIXME: we assume that the transport has been connected, enforce
- * that somehow, we also want to be called from _negotiate
- */
-int git_fetch_list_want(git_headarray *whn_list, git_remote *remote)
+int filter_wants(git_remote *remote)
 {
 	git_vector list;
 	git_headarray refs;
@@ -122,8 +119,8 @@ int git_fetch_list_want(git_headarray *whn_list, git_remote *remote)
 	}
 
 	git_vector_sort(&list);
-	whn_list->len = list.length;
-	whn_list->heads = (git_remote_head **) list.contents;
+	remote->refs.len = list.length;
+	remote->refs.heads = (git_remote_head **) list.contents;
 
 	return GIT_SUCCESS;
 
@@ -137,19 +134,24 @@ cleanup:
  * them out. When we get an ACK we hide that commit and continue
  * traversing until we're done
  */
-int git_fetch_negotiate(git_headarray *list, git_remote *remote)
+int git_fetch_negotiate(git_remote *remote)
 {
 	git_revwalk *walk;
 	int error;
 	unsigned int i;
 	git_reference *ref;
 	git_strarray refs;
+	git_headarray *list = &remote->refs;
 	git_repository *repo = remote->repo;
 	git_oid oid;
 
+	error = filter_wants(remote);
+	if (error < GIT_SUCCESS)
+		return git__rethrow(error, "Failed to filter the reference list for wants");
+
 	/* Don't try to negotiate when we don't want anything */
 	if (list->len == 0)
-		return GIT_EINVALIDARGS;
+		return GIT_SUCCESS;
 
 	/*
 	 * Now we have everything set up so we can start tell the server

src/fetch.h

@@ -0,0 +1,6 @@
+#ifndef INCLUDE_fetch_h__
+#define INCLUDE_fetch_h__
+
+int git_fetch_negotiate(git_remote *remote);
+
+#endif

src/remote.c

@@ -30,6 +30,7 @@
 #include "config.h"
 #include "repository.h"
 #include "remote.h"
+#include "fetch.h"
 
 static int refspec_parse(git_refspec *refspec, const char *str)
 {
@@ -202,6 +203,16 @@ int git_remote_ls(git_remote *remote, git_headarray *refs)
 	return git_transport_ls(remote->transport, refs);
 }
 
+int git_remote_negotiate(git_remote *remote)
+{
+	return git_fetch_negotiate(remote);
+}
+
+git_headarray *git_remote_tips(git_remote *remote)
+{
+	return &remote->refs;
+}
+
 void git_remote_free(git_remote *remote)
 {
 	free(remote->fetch.src);

src/remote.h

@@ -8,6 +8,7 @@
 struct git_remote {
 	char *name;
 	char *url;
+	git_headarray refs;
 	struct git_refspec fetch;
 	struct git_refspec push;
 	git_transport *transport;