text: /*
   * Copyright (C) the libgit2 contributors. All rights reserved.
   *
   * This file is part of libgit2, distributed under the GNU GPL v2 with
   * a Linking Exception. For full terms see the included COPYING file.
   */
  #include "git2.h"
  #include "vector.h"
  #include "netops.h"
  #include "buffer.h"
  #include "push.h"
  #include "git2/sys/transport.h"
  
  #define GIT_SIDE_BAND_DATA     1
  #define GIT_SIDE_BAND_PROGRESS 2
  #define GIT_SIDE_BAND_ERROR    3
  
  #define GIT_CAP_OFS_DELTA "ofs-delta"
  #define GIT_CAP_MULTI_ACK "multi_ack"
  #define GIT_CAP_MULTI_ACK_DETAILED "multi_ack_detailed"
  #define GIT_CAP_SIDE_BAND "side-band"
  #define GIT_CAP_SIDE_BAND_64K "side-band-64k"
  #define GIT_CAP_INCLUDE_TAG "include-tag"
  #define GIT_CAP_DELETE_REFS "delete-refs"
  #define GIT_CAP_REPORT_STATUS "report-status"
  #define GIT_CAP_THIN_PACK "thin-pack"
  #define GIT_CAP_SYMREF "symref"
  
  enum git_pkt_type {
  	GIT_PKT_CMD,
  	GIT_PKT_FLUSH,
  	GIT_PKT_REF,
  	GIT_PKT_HAVE,
  	GIT_PKT_ACK,
  	GIT_PKT_NAK,
  	GIT_PKT_PACK,
  	GIT_PKT_COMMENT,
  	GIT_PKT_ERR,
  	GIT_PKT_DATA,
  	GIT_PKT_PROGRESS,
  	GIT_PKT_OK,
  	GIT_PKT_NG,
  	GIT_PKT_UNPACK,
  };
  
  /* Used for multi_ack and mutli_ack_detailed */
  enum git_ack_status {
  	GIT_ACK_NONE,
  	GIT_ACK_CONTINUE,
  	GIT_ACK_COMMON,
  	GIT_ACK_READY
  };
  
  /* This would be a flush pkt */
  typedef struct {
  	enum git_pkt_type type;
  } git_pkt;
  
  struct git_pkt_cmd {
  	enum git_pkt_type type;
  	char *cmd;
  	char *path;
  	char *host;
  };
  
  /* This is a pkt-line with some info in it */
  typedef struct {
  	enum git_pkt_type type;
  	git_remote_head head;
  	char *capabilities;
  } git_pkt_ref;
  
  /* Useful later */
  typedef struct {
  	enum git_pkt_type type;
  	git_oid oid;
  	enum git_ack_status status;
  } git_pkt_ack;
  
  typedef struct {
  	enum git_pkt_type type;
  	char comment[GIT_FLEX_ARRAY];
  } git_pkt_comment;
  
  typedef struct {
  	enum git_pkt_type type;
  	int len;
  	char data[GIT_FLEX_ARRAY];
  } git_pkt_data;
  
  typedef git_pkt_data git_pkt_progress;
  
  typedef struct {
  	enum git_pkt_type type;
  	int len;
  	char error[GIT_FLEX_ARRAY];
  } git_pkt_err;
  
  typedef struct {
  	enum git_pkt_type type;
  	char *ref;
  } git_pkt_ok;
  
  typedef struct {
  	enum git_pkt_type type;
  	char *ref;
  	char *msg;
  } git_pkt_ng;
  
  typedef struct {
  	enum git_pkt_type type;
  	int unpack_ok;
  } git_pkt_unpack;
  
  typedef struct transport_smart_caps {
  	int common:1,
  		ofs_delta:1,
  		multi_ack: 1,
  		multi_ack_detailed: 1,
  		side_band:1,
  		side_band_64k:1,
  		include_tag:1,
  		delete_refs:1,
  		report_status:1,
  		thin_pack:1;
  } transport_smart_caps;
  
  typedef int (*packetsize_cb)(size_t received, void *payload);
  
  typedef struct {
  	git_transport parent;
  	git_remote *owner;
  	char *url;
  	git_cred_acquire_cb cred_acquire_cb;
  	void *cred_acquire_payload;
  	int direction;
  	int flags;
  	git_transport_message_cb progress_cb;
  	git_transport_message_cb error_cb;
  	git_transport_certificate_check_cb certificate_check_cb;
  	void *message_cb_payload;
  	git_smart_subtransport *wrapped;
  	git_smart_subtransport_stream *current_stream;
  	transport_smart_caps caps;
  	git_vector refs;
  	git_vector heads;
  	git_vector common;
  	git_atomic cancelled;
  	packetsize_cb packetsize_cb;
  	void *packetsize_payload;
  	unsigned rpc : 1,
  		have_refs : 1,
  		connected : 1;
  	gitno_buffer buffer;
  	char buffer_data[65536];
  } transport_smart;
  
  /* smart_protocol.c */
  int git_smart__store_refs(transport_smart *t, int flushes);
  int git_smart__detect_caps(git_pkt_ref *pkt, transport_smart_caps *caps, git_vector *symrefs);
  int git_smart__push(git_transport *transport, git_push *push);
  
  int git_smart__negotiate_fetch(
  	git_transport *transport,
  	git_repository *repo,
  	const git_remote_head * const *refs,
  	size_t count);
  
  int git_smart__download_pack(
  	git_transport *transport,
  	git_repository *repo,
  	git_transfer_progress *stats,
  	git_transfer_progress_cb progress_cb,
  	void *progress_payload);
  
  /* smart.c */
  int git_smart__negotiation_step(git_transport *transport, void *data, size_t len);
  int git_smart__get_push_stream(transport_smart *t, git_smart_subtransport_stream **out);
  
  int git_smart__update_heads(transport_smart *t, git_vector *symrefs);
  
  /* smart_pkt.c */
  int git_pkt_parse_line(git_pkt **head, const char *line, const char **out, size_t len);
  int git_pkt_buffer_flush(git_buf *buf);
  int git_pkt_send_flush(GIT_SOCKET s);
  int git_pkt_buffer_done(git_buf *buf);
  int git_pkt_buffer_wants(const git_remote_head * const *refs, size_t count, transport_smart_caps *caps, git_buf *buf);
  int git_pkt_buffer_have(git_oid *oid, git_buf *buf);
  void git_pkt_free(git_pkt *pkt);
  