transport.hon commit log_ref_setup(): improve robustness against races (1fb0c80)
   1#ifndef TRANSPORT_H
   2#define TRANSPORT_H
   3
   4#include "cache.h"
   5#include "run-command.h"
   6#include "remote.h"
   7
   8struct string_list;
   9
  10struct git_transport_options {
  11        unsigned thin : 1;
  12        unsigned keep : 1;
  13        unsigned followtags : 1;
  14        unsigned check_self_contained_and_connected : 1;
  15        unsigned self_contained_and_connected : 1;
  16        unsigned update_shallow : 1;
  17        unsigned deepen_relative : 1;
  18        int depth;
  19        const char *deepen_since;
  20        const struct string_list *deepen_not;
  21        const char *uploadpack;
  22        const char *receivepack;
  23        struct push_cas_option *cas;
  24};
  25
  26enum transport_family {
  27        TRANSPORT_FAMILY_ALL = 0,
  28        TRANSPORT_FAMILY_IPV4,
  29        TRANSPORT_FAMILY_IPV6
  30};
  31
  32struct transport {
  33        struct remote *remote;
  34        const char *url;
  35        void *data;
  36        const struct ref *remote_refs;
  37
  38        /**
  39         * Indicates whether we already called get_refs_list(); set by
  40         * transport.c::transport_get_remote_refs().
  41         */
  42        unsigned got_remote_refs : 1;
  43
  44        /*
  45         * Transports that call take-over destroys the data specific to
  46         * the transport type while doing so, and cannot be reused.
  47         */
  48        unsigned cannot_reuse : 1;
  49
  50        /*
  51         * A hint from caller that it will be performing a clone, not
  52         * normal fetch. IOW the repository is guaranteed empty.
  53         */
  54        unsigned cloning : 1;
  55
  56        /*
  57         * These strings will be passed to the {pre, post}-receive hook,
  58         * on the remote side, if both sides support the push options capability.
  59         */
  60        const struct string_list *push_options;
  61
  62        /**
  63         * Returns 0 if successful, positive if the option is not
  64         * recognized or is inapplicable, and negative if the option
  65         * is applicable but the value is invalid.
  66         **/
  67        int (*set_option)(struct transport *connection, const char *name,
  68                          const char *value);
  69
  70        /**
  71         * Returns a list of the remote side's refs. In order to allow
  72         * the transport to try to share connections, for_push is a
  73         * hint as to whether the ultimate operation is a push or a fetch.
  74         *
  75         * If the transport is able to determine the remote hash for
  76         * the ref without a huge amount of effort, it should store it
  77         * in the ref's old_sha1 field; otherwise it should be all 0.
  78         **/
  79        struct ref *(*get_refs_list)(struct transport *transport, int for_push);
  80
  81        /**
  82         * Fetch the objects for the given refs. Note that this gets
  83         * an array, and should ignore the list structure.
  84         *
  85         * If the transport did not get hashes for refs in
  86         * get_refs_list(), it should set the old_sha1 fields in the
  87         * provided refs now.
  88         **/
  89        int (*fetch)(struct transport *transport, int refs_nr, struct ref **refs);
  90
  91        /**
  92         * Push the objects and refs. Send the necessary objects, and
  93         * then, for any refs where peer_ref is set and
  94         * peer_ref->new_oid is different from old_oid, tell the
  95         * remote side to update each ref in the list from old_oid to
  96         * peer_ref->new_oid.
  97         *
  98         * Where possible, set the status for each ref appropriately.
  99         *
 100         * The transport must modify new_sha1 in the ref to the new
 101         * value if the remote accepted the change. Note that this
 102         * could be a different value from peer_ref->new_oid if the
 103         * process involved generating new commits.
 104         **/
 105        int (*push_refs)(struct transport *transport, struct ref *refs, int flags);
 106        int (*push)(struct transport *connection, int refspec_nr, const char **refspec, int flags);
 107        int (*connect)(struct transport *connection, const char *name,
 108                       const char *executable, int fd[2]);
 109
 110        /** get_refs_list(), fetch(), and push_refs() can keep
 111         * resources (such as a connection) reserved for further
 112         * use. disconnect() releases these resources.
 113         **/
 114        int (*disconnect)(struct transport *connection);
 115        char *pack_lockfile;
 116        signed verbose : 3;
 117        /**
 118         * Transports should not set this directly, and should use this
 119         * value without having to check isatty(2), -q/--quiet
 120         * (transport->verbose < 0), etc. - checking has already been done
 121         * in transport_set_verbosity().
 122         **/
 123        unsigned progress : 1;
 124        /*
 125         * If transport is at least potentially smart, this points to
 126         * git_transport_options structure to use in case transport
 127         * actually turns out to be smart.
 128         */
 129        struct git_transport_options *smart_options;
 130
 131        enum transport_family family;
 132};
 133
 134#define TRANSPORT_PUSH_ALL 1
 135#define TRANSPORT_PUSH_FORCE 2
 136#define TRANSPORT_PUSH_DRY_RUN 4
 137#define TRANSPORT_PUSH_MIRROR 8
 138#define TRANSPORT_PUSH_PORCELAIN 16
 139#define TRANSPORT_PUSH_SET_UPSTREAM 32
 140#define TRANSPORT_RECURSE_SUBMODULES_CHECK 64
 141#define TRANSPORT_PUSH_PRUNE 128
 142#define TRANSPORT_RECURSE_SUBMODULES_ON_DEMAND 256
 143#define TRANSPORT_PUSH_NO_HOOK 512
 144#define TRANSPORT_PUSH_FOLLOW_TAGS 1024
 145#define TRANSPORT_PUSH_CERT_ALWAYS 2048
 146#define TRANSPORT_PUSH_CERT_IF_ASKED 4096
 147#define TRANSPORT_PUSH_ATOMIC 8192
 148#define TRANSPORT_PUSH_OPTIONS 16384
 149
 150extern int transport_summary_width(const struct ref *refs);
 151
 152/* Returns a transport suitable for the url */
 153struct transport *transport_get(struct remote *, const char *);
 154
 155/*
 156 * Check whether a transport is allowed by the environment.
 157 *
 158 * Type should generally be the URL scheme, as described in
 159 * Documentation/git.txt
 160 *
 161 * from_user specifies if the transport was given by the user.  If unknown pass
 162 * a -1 to read from the environment to determine if the transport was given by
 163 * the user.
 164 *
 165 */
 166int is_transport_allowed(const char *type, int from_user);
 167
 168/*
 169 * Check whether a transport is allowed by the environment,
 170 * and die otherwise.
 171 */
 172void transport_check_allowed(const char *type);
 173
 174/* Transport options which apply to git:// and scp-style URLs */
 175
 176/* The program to use on the remote side to send a pack */
 177#define TRANS_OPT_UPLOADPACK "uploadpack"
 178
 179/* The program to use on the remote side to receive a pack */
 180#define TRANS_OPT_RECEIVEPACK "receivepack"
 181
 182/* Transfer the data as a thin pack if not null */
 183#define TRANS_OPT_THIN "thin"
 184
 185/* Check the current value of the remote ref */
 186#define TRANS_OPT_CAS "cas"
 187
 188/* Keep the pack that was transferred if not null */
 189#define TRANS_OPT_KEEP "keep"
 190
 191/* Limit the depth of the fetch if not null */
 192#define TRANS_OPT_DEPTH "depth"
 193
 194/* Limit the depth of the fetch based on time if not null */
 195#define TRANS_OPT_DEEPEN_SINCE "deepen-since"
 196
 197/* Limit the depth of the fetch based on revs if not null */
 198#define TRANS_OPT_DEEPEN_NOT "deepen-not"
 199
 200/* Limit the deepen of the fetch if not null */
 201#define TRANS_OPT_DEEPEN_RELATIVE "deepen-relative"
 202
 203/* Aggressively fetch annotated tags if possible */
 204#define TRANS_OPT_FOLLOWTAGS "followtags"
 205
 206/* Accept refs that may update .git/shallow without --depth */
 207#define TRANS_OPT_UPDATE_SHALLOW "updateshallow"
 208
 209/* Send push certificates */
 210#define TRANS_OPT_PUSH_CERT "pushcert"
 211
 212/**
 213 * Returns 0 if the option was used, non-zero otherwise. Prints a
 214 * message to stderr if the option is not used.
 215 **/
 216int transport_set_option(struct transport *transport, const char *name,
 217                         const char *value);
 218void transport_set_verbosity(struct transport *transport, int verbosity,
 219        int force_progress);
 220
 221#define REJECT_NON_FF_HEAD     0x01
 222#define REJECT_NON_FF_OTHER    0x02
 223#define REJECT_ALREADY_EXISTS  0x04
 224#define REJECT_FETCH_FIRST     0x08
 225#define REJECT_NEEDS_FORCE     0x10
 226
 227int transport_push(struct transport *connection,
 228                   int refspec_nr, const char **refspec, int flags,
 229                   unsigned int * reject_reasons);
 230
 231const struct ref *transport_get_remote_refs(struct transport *transport);
 232
 233int transport_fetch_refs(struct transport *transport, struct ref *refs);
 234void transport_unlock_pack(struct transport *transport);
 235int transport_disconnect(struct transport *transport);
 236char *transport_anonymize_url(const char *url);
 237void transport_take_over(struct transport *transport,
 238                         struct child_process *child);
 239
 240int transport_connect(struct transport *transport, const char *name,
 241                      const char *exec, int fd[2]);
 242
 243/* Transport methods defined outside transport.c */
 244int transport_helper_init(struct transport *transport, const char *name);
 245int bidirectional_transfer_loop(int input, int output);
 246
 247/* common methods used by transport.c and builtin/send-pack.c */
 248void transport_verify_remote_names(int nr_heads, const char **heads);
 249
 250void transport_update_tracking_ref(struct remote *remote, struct ref *ref, int verbose);
 251
 252int transport_refs_pushed(struct ref *ref);
 253
 254void transport_print_push_status(const char *dest, struct ref *refs,
 255                  int verbose, int porcelain, unsigned int *reject_reasons);
 256
 257typedef void alternate_ref_fn(const struct ref *, void *);
 258extern void for_each_alternate_ref(alternate_ref_fn, void *);
 259#endif