From e967ca38473a05abf3e8f7a025c6b9bee487aa4f Mon Sep 17 00:00:00 2001 From: Jonathan Tan Date: Thu, 14 Dec 2017 13:44:45 -0800 Subject: transport: make transport vtable more private Move the definition of the transport-specific functions provided by transports, whether declared in transport.c or transport-helper.c, into an internal header. This means that transport-using code (as opposed to transport-declaring code) can no longer access these functions (without importing the internal header themselves), making it clear that they should use the transport_*() functions instead, and also allowing the interface between the transport mechanism and an individual transport to independently evolve. This is superficially a reversal of commit 824d5776c3f2 ("Refactor struct transport_ops inlined into struct transport", 2007-09-19). However, the scope of the involved variables was neither affected nor discussed in that commit, and I think that the advantages in making those functions more private outweigh the advantages described in that commit's commit message. A minor additional point is that the code has gotten more complicated since then, in that the function-pointer variables are potentially mutated twice (once initially and once if transport_take_over() is invoked), increasing the value of corralling them into their own struct. Signed-off-by: Jonathan Tan Signed-off-by: Junio C Hamano --- transport-internal.h | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 transport-internal.h (limited to 'transport-internal.h') diff --git a/transport-internal.h b/transport-internal.h new file mode 100644 index 0000000000..3c1a29d727 --- /dev/null +++ b/transport-internal.h @@ -0,0 +1,61 @@ +#ifndef TRANSPORT_INTERNAL_H +#define TRANSPORT_INTERNAL_H + +struct ref; +struct transport; + +struct transport_vtable { + /** + * Returns 0 if successful, positive if the option is not + * recognized or is inapplicable, and negative if the option + * is applicable but the value is invalid. + **/ + int (*set_option)(struct transport *connection, const char *name, + const char *value); + /** + * Returns a list of the remote side's refs. In order to allow + * the transport to try to share connections, for_push is a + * hint as to whether the ultimate operation is a push or a fetch. + * + * If the transport is able to determine the remote hash for + * the ref without a huge amount of effort, it should store it + * in the ref's old_sha1 field; otherwise it should be all 0. + **/ + struct ref *(*get_refs_list)(struct transport *transport, int for_push); + + /** + * Fetch the objects for the given refs. Note that this gets + * an array, and should ignore the list structure. + * + * If the transport did not get hashes for refs in + * get_refs_list(), it should set the old_sha1 fields in the + * provided refs now. + **/ + int (*fetch)(struct transport *transport, int refs_nr, struct ref **refs); + + /** + * Push the objects and refs. Send the necessary objects, and + * then, for any refs where peer_ref is set and + * peer_ref->new_oid is different from old_oid, tell the + * remote side to update each ref in the list from old_oid to + * peer_ref->new_oid. + * + * Where possible, set the status for each ref appropriately. + * + * The transport must modify new_sha1 in the ref to the new + * value if the remote accepted the change. Note that this + * could be a different value from peer_ref->new_oid if the + * process involved generating new commits. + **/ + int (*push_refs)(struct transport *transport, struct ref *refs, int flags); + int (*connect)(struct transport *connection, const char *name, + const char *executable, int fd[2]); + + /** get_refs_list(), fetch(), and push_refs() can keep + * resources (such as a connection) reserved for further + * use. disconnect() releases these resources. + **/ + int (*disconnect)(struct transport *connection); +}; + +#endif -- cgit v1.2.3