libgit2/CHANGELOG.md

v0.25 + 1

Changes or improvements

• GIT_MERGE_OPTIONS_INIT now includes a setting to perform rename detection. This aligns this structure with the default by git_merge and git_merge_trees when NULL was provided for the options.

API additions

• You can now set the default share mode on Windows for opening files using GIT_OPT_SET_WINDOWS_SHAREMODE option with git_libgit2_opts(). You can query the current share mode with GIT_OPT_GET_WINDOWS_SHAREMODE.

API removals

Breaking API changes

• clone_checkout_strategy has been removed from git_submodule_update_option. The checkout strategy used to clone will be the same strategy specified in checkout_opts.

v0.25

Changes or improvements

• Fix repository discovery with git_repository_discover and git_repository_open_ext to match git's handling of a ceiling directory at the current directory. git only checks ceiling directories when its search ascends to a parent directory. A ceiling directory matching the starting directory will not prevent git from finding a repository in the starting directory or a parent directory.

• Do not fail when deleting remotes in the presence of broken global configs which contain branches.

• Support for reading and writing git index v4 files

• Improve the performance of the revwalk and bring us closer to git's code.

• The reference db has improved support for concurrency and returns GIT_ELOCKED when an operation could not be performed due to locking.

• Nanosecond resolution is now activated by default, following git's change to do this.

• We now restrict the set of ciphers we let OpenSSL use by default.

• Users can now register their own merge drivers for use with .gitattributes. The library also gained built-in support for the union merge driver.

• The default for creating references is now to validate that the object does exist.

• Add git_proxy_options which is used by the different networking implementations to let the caller specify the proxy settings instead of relying on the environment variables.

API additions

• You can now get the user-agent used by libgit2 using the GIT_OPT_GET_USER_AGENT option with git_libgit2_opts(). It is the counterpart to GIT_OPT_SET_USER_AGENT.

• The GIT_OPT_SET_SSL_CIPHERS option for git_libgit2_opts() lets you specify a custom list of ciphers to use for OpenSSL.

• git_commit_create_buffer() creates a commit and writes it into a user-provided buffer instead of writing it into the object db. Combine it with git_commit_create_with_signature() in order to create a commit with a cryptographic signature.

• git_blob_create_fromstream() and git_blob_create_fromstream_commit() allow you to create a blob by writing into a stream. Useful when you do not know the final size or want to copy the contents from another stream.

• New flags for git_repository_open_ext:

  • GIT_REPOSITORY_OPEN_NO_DOTGIT - Do not check for a repository by appending /.git to the start_path; only open the repository if start_path itself points to the git directory.
  • GIT_REPOSITORY_OPEN_FROM_ENV - Find and open a git repository, respecting the environment variables used by the git command-line tools. If set, git_repository_open_ext will ignore the other flags and the ceiling_dirs argument, and will allow a NULL path to use GIT_DIR or search from the current directory. The search for a repository will respect $GIT_CEILING_DIRECTORIES and $GIT_DISCOVERY_ACROSS_FILESYSTEM. The opened repository will respect $GIT_INDEX_FILE, $GIT_NAMESPACE, $GIT_OBJECT_DIRECTORY, and $GIT_ALTERNATE_OBJECT_DIRECTORIES. In the future, this flag will also cause git_repository_open_ext to respect $GIT_WORK_TREE and $GIT_COMMON_DIR; currently, git_repository_open_ext with this flag will error out if either $GIT_WORK_TREE or $GIT_COMMON_DIR is set.

• git_diff_from_buffer() can create a git_diff object from the contents of a git-style patch file.

• git_index_version() and git_index_set_version() to get and set the index version

• git_odb_expand_ids() lets you check for the existence of multiple objects at once.

• The new git_blob_dup(), git_commit_dup(), git_tag_dup() and git_tree_dup() functions provide type-specific wrappers for git_object_dup() to reduce noise and increase type safety for callers.

• git_reference_dup() lets you duplicate a reference to aid in ownership management and cleanup.

• git_signature_from_buffer() lets you create a signature from a string in the format that appear in objects.

• git_tree_create_updated() lets you create a tree based on another one together with a list of updates. For the covered update cases, it's more efficient than the git_index route.

• git_apply_patch() applies hunks from a git_patch to a buffer.

• git_diff_to_buf() lets you print an entire diff directory to a buffer, similar to how git_patch_to_buf() works.

• git_proxy_init_options() is added to initialize a git_proxy_options structure at run-time.

• git_merge_driver_register(), git_merge_driver_unregister() let you register and unregister a custom merge driver to be used when .gitattributes specifies it.

• git_merge_driver_lookup() can be used to look up a merge driver by name.

• git_merge_driver_source_repo(), git_merge_driver_source_ancestor(), git_merge_driver_source_ours(), git_merge_driver_source_theirs(), git_merge_driver_source_file_options() added as accessors to git_merge_driver_source.

API removals

• git_blob_create_fromchunks() has been removed in favour of git_blob_create_fromstream().

Breaking API changes

• git_packbuilder_object_count and git_packbuilder_written now return a size_t instead of a uint32_t for more thorough compatibility with the rest of the library.

• git_packbuiler_progress now provides explicitly sized uint32_t values instead of unsigned int.

• git_diff_file now includes an id_abbrev field that reflects the number of nibbles set in the id field.

• git_odb_backend now has a freshen function pointer. This optional function pointer is similar to the exists function, but it will update a last-used marker. For filesystem-based object databases, this updates the timestamp of the file containing the object, to indicate "freshness". If this is NULL, then it will not be called and the exists function will be used instead.

• git_remote_connect() now accepts git_proxy_options argument, and git_fetch_options and git_push_options each have a proxy_opts field.

• git_merge_options now provides a default_driver that can be used to provide the name of a merge driver to be used to handle files changed during a merge.

v0.24

Changes or improvements

• Custom merge drivers can now be registered, which allows callers to configure callbacks to honor merge=driver configuration in .gitattributes.

• Custom filters can now be registered with wildcard attributes, for example filter=*. Consumers should examine the attributes parameter of the check function for details.

• Symlinks are now followed when locking a file, which can be necessary when multiple worktrees share a base repository.

• You can now set your own user-agent to be sent for HTTP requests by using the GIT_OPT_SET_USER_AGENT with git_libgit2_opts().

• You can set custom HTTP header fields to be sent along with requests by passing them in the fetch and push options.

• Tree objects are now assumed to be sorted. If a tree is not correctly formed, it will give bad results. This is the git approach and cuts a significant amount of time when reading the trees.

• Filter registration is now protected against concurrent registration.

• Filenames which are not valid on Windows in an index no longer cause to fail to parse it on that OS.

• Rebases can now be performed purely in-memory, without touching the repository's workdir.

• When adding objects to the index, or when creating new tree or commit objects, the inputs are validated to ensure that the dependent objects exist and are of the correct type. This object validation can be disabled with the GIT_OPT_ENABLE_STRICT_OBJECT_CREATION option.

• The WinHTTP transport's handling of bad credentials now behaves like the others, asking for credentials again.

API additions

• git_config_lock() has been added, which allow for transactional/atomic complex updates to the configuration, removing the opportunity for concurrent operations and not committing any changes until the unlock.

• git_diff_options added a new callback progress_cb to report on the progress of the diff as files are being compared. The documentation of the existing callback notify_cb was updated to reflect that it only gets called when new deltas are added to the diff.

• git_fetch_options and git_push_options have gained a custom_headers field to set the extra HTTP header fields to send.

• git_stream_register_tls() lets you register a callback to be used as the constructor for a TLS stream instead of the libgit2 built-in one.

• git_commit_header_field() allows you to look up a specific header field in a commit.

• git_commit_extract_signature() extracts the signature from a commit and gives you both the signature and the signed data so you can verify it.

API removals

• No APIs were removed in this version.

Breaking API changes

• The git_merge_tree_flag_t is now git_merge_flag_t. Subsequently, its members are no longer prefixed with GIT_MERGE_TREE_FLAG but are now prefixed with GIT_MERGE_FLAG, and the tree_flags field of the git_merge_options structure is now named flags.

• The git_merge_file_flags_t enum is now git_merge_file_flag_t for consistency with other enum type names.

• git_cert descendent types now have a proper parent member

• It is the responsibility of the refdb backend to decide what to do with the reflog on ref deletion. The file-based backend must delete it, a database-backed one may wish to archive it.

• git_config_backend has gained two entries. lock and unlock with which to implement the transactional/atomic semantics for the configuration backend.

• git_index_add and git_index_conflict_add() will now use the case as provided by the caller on case insensitive systems. Previous versions would keep the case as it existed in the index. This does not affect the higher-level git_index_add_bypath or git_index_add_frombuffer functions.

• The notify_payload field of git_diff_options was renamed to payload to reflect that it's also the payload for the new progress callback.

• The git_config_level_t enum has gained a higher-priority value GIT_CONFIG_LEVEL_PROGRAMDATA which represent a rough Windows equivalent to the system level configuration.

• git_rebase_options now has a merge_options field.

• The index no longer performs locking itself. This is not something users of the library should have been relying on as it's not part of the concurrency guarantees.

• git_remote_connect() now takes a custom_headers argument to set the extra HTTP header fields to send.

v0.23

Changes or improvements

• Patience and minimal diff drivers can now be used for merges.

• Merges can now ignore whitespace changes.

• Updated binary identification in CRLF filtering to avoid false positives in UTF-8 files.

• Rename and copy detection is enabled for small files.

• Checkout can now handle an initial checkout of a repository, making GIT_CHECKOUT_SAFE_CREATE unnecessary for users of clone.

• The signature parameter in the ref-modifying functions has been removed. Use git_repository_set_ident() and git_repository_ident() to override the signature to be used.

• The local transport now auto-scales the number of threads to use when creating the packfile instead of sticking to one.

• Reference renaming now uses the right id for the old value.

• The annotated version of branch creation, HEAD detaching and reset allow for specifying the expression from the user to be put into the reflog.

• git_rebase_commit now returns GIT_EUNMERGED when you attempt to commit with unstaged changes.

• On Mac OS X, we now use SecureTransport to provide the cryptographic support for HTTPS connections insead of OpenSSL.

• Checkout can now accept an index for the baseline computations via the baseline_index member.

• The configuration for fetching is no longer stored inside the git_remote struct but has been moved to a git_fetch_options. The remote functions now take these options or the callbacks instead of setting them beforehand.

• git_submodule instances are no longer cached or shared across lookup. Each submodule represents the configuration at the time of loading.

• The index now uses diffs for add_all() and update_all() which gives it a speed boost and closer semantics to git.

• The ssh transport now reports the stderr output from the server as the error message, which allows you to get the "repository not found" messages.

• git_index_conflict_add() will remove staged entries that exist for conflicted paths.

• The flags for a git_diff_file will now have the GIT_DIFF_FLAG_EXISTS bit set when a file exists on that side of the diff. This is useful for understanding whether a side of the diff exists in the presence of a conflict.

• The constructor for a write-stream into the odb now takes git_off_t instead of size_t for the size of the blob, which allows putting large files into the odb on 32-bit systems.

• The remote's push and pull URLs now honor the url.$URL.insteadOf configuration. This allows modifying URL prefixes to a custom value via gitconfig.

• git_diff_foreach, git_diff_blobs, git_diff_blob_to_buffer, and git_diff_buffers now accept a new binary callback of type git_diff_binary_cb that includes the binary diff information.

• The race condition mitigations described in racy-git.txt have been implemented.

• If libcurl is installed, we will use it to connect to HTTP(S) servers.

API additions

• The git_merge_options gained a file_flags member.

• Parsing and retrieving a configuration value as a path is exposed via git_config_parse_path() and git_config_get_path() respectively.

• git_repository_set_ident() and git_repository_ident() serve to set and query which identity will be used when writing to the reflog.

• git_config_entry_free() frees a config entry.

• git_config_get_string_buf() provides a way to safely retrieve a string from a non-snapshot configuration.

• git_annotated_commit_from_revspec() allows to get an annotated commit from an extended sha synatx string.

• git_repository_set_head_detached_from_annotated(), git_branch_create_from_annotated() and git_reset_from_annotated() allow for the caller to provide an annotated commit through which they can control what expression is put into the reflog as the source/target.

• git_index_add_frombuffer() can now create a blob from memory buffer and add it to the index which is attached to a repository.

• The structure git_fetch_options has been added to determine the runtime configuration for fetching, such as callbacks, pruning and autotag behaviour. It has the runtime initializer git_fetch_init_options().

• The enum git_fetch_prune_t has been added, letting you specify the pruning behaviour for a fetch.

• A push operation will notify the caller of what updates it indends to perform on the remote, which provides similar information to git's pre-push hook.

• git_stash_apply() can now apply a stashed state from the stash list, placing the data into the working directory and index.

• git_stash_pop() will apply a stashed state (like git_stash_apply()) but will remove the stashed state after a successful application.

• A new error code GIT_EEOF indicates an early EOF from the server. This typically indicates an error with the URL or configuration of the server, and tools can use this to show messages about failing to communicate with the server.

• A new error code GIT_EINVALID indicates that an argument to a function is invalid, or an invalid operation was requested.

• git_diff_index_to_workdir() and git_diff_tree_to_index() will now produce deltas of type GIT_DELTA_CONFLICTED to indicate that the index side of the delta is a conflict.

• The git_status family of functions will now produce status of type GIT_STATUS_CONFLICTED to indicate that a conflict exists for that file in the index.

• git_index_entry_is_conflict() is a utility function to determine if a given index entry has a non-zero stage entry, indicating that it is one side of a conflict.

• It is now possible to pass a keypair via a buffer instead of a path. For this, GIT_CREDTYPE_SSH_MEMORY and git_cred_ssh_key_memory_new() have been added.

• git_filter_list_contains will indicate whether a particular filter will be run in the given filter list.

• git_commit_header_field() has been added, which allows retrieving the contents of an arbitrary header field.

• git_submodule_set_branch() allows to set the configured branch for a submodule.

API removals

• git_remote_save() and git_remote_clear_refspecs() have been removed. Remote's configuration is changed via the configuration directly or through a convenience function which performs changes to the configuration directly.

• git_remote_set_callbacks(), git_remote_get_callbacks() and git_remote_set_transport() have been removed and the remote no longer stores this configuration.

• git_remote_set_fetch_refpecs() and git_remote_set_push_refspecs() have been removed. There is no longer a way to set the base refspecs at run-time.

• git_submodule_save() has been removed. The submodules are no longer configured via the objects.

• git_submodule_reload_all() has been removed as we no longer cache submodules.

Breaking API changes

• git_smart_subtransport_cb now has a param parameter.

• The git_merge_options structure member flags has been renamed to tree_flags.

• The git_merge_file_options structure member flags is now an unsigned int. It was previously a git_merge_file_flags_t.

• GIT_CHECKOUT_SAFE_CREATE has been removed. Most users will generally be able to switch to GIT_CHECKOUT_SAFE, but if you require missing file handling during checkout, you may now use GIT_CHECKOUT_SAFE | GIT_CHECKOUT_RECREATE_MISSING.

• The git_clone_options and git_submodule_update_options structures no longer have a signature field.

• The following functions have removed the signature and/or log message parameters in favour of git-emulating ones.

  • git_branch_create(), git_branch_move()
  • git_rebase_init(), git_rebase_abort()
  • git_reference_symbolic_create_matching(), git_reference_symbolic_create(), git_reference_create(), git_reference_create_matching(), git_reference_symbolic_set_target(), git_reference_set_target(), git_reference_rename()
  • git_remote_update_tips(), git_remote_fetch(), git_remote_push()
  • git_repository_set_head(), git_repository_set_head_detached(), git_repository_detach_head()
  • git_reset()

• git_config_get_entry() now gives back a ref-counted git_config_entry. You must free it when you no longer need it.

• git_config_get_string() will return an error if used on a non-snapshot configuration, as there can be no guarantee that the returned pointer is valid.

• git_note_default_ref() now uses a git_buf to return the string, as the string is otherwise not guaranteed to stay allocated.

• git_rebase_operation_current() will return GIT_REBASE_NO_OPERATION if it is called immediately after creating a rebase session but before you have applied the first patch.

• git_rebase_options now contains a git_checkout_options struct that will be used for functions that modify the working directory, namely git_rebase_init, git_rebase_next and git_rebase_abort. As a result, git_rebase_open now also takes a git_rebase_options and only the git_rebase_init and git_rebase_open functions take a git_rebase_options, where they will persist the options to subsequent git_rebase calls.

• The git_clone_options struct now has fetch options in a fetch_opts field instead of remote callbacks in remote_callbacks.

• The remote callbacks has gained a new member push_negotiation which gets called before sending the update commands to the server.

• The following functions no longer act on a remote instance but change the repository's configuration. Their signatures have changed accordingly:

  • git_remote_set_url(), git_remote_seturl()
  • git_remote_add_fetch(), git_remote_add_push() and
  • git_remote_set_autotag()

• git_remote_connect() and git_remote_prune() now take a pointer to the callbacks.

• git_remote_fetch() and git_remote_download() now take a pointer to fetch options which determine the runtime configuration.

• The git_remote_autotag_option_t values have been changed. It has gained a _UNSPECIFIED default value to specify no override for the configured setting.

• git_remote_update_tips() now takes a pointer to the callbacks as well as a boolean whether to write FETCH_HEAD and the autotag setting.

• git_remote_create_anonymous() no longer takes a fetch refspec as url-only remotes cannot have configured refspecs.

• The git_submodule_update_options struct now has fetch options in the fetch_opts field instead of callbacks in the remote_callbacks field.

• The following functions no longer act on a submodule instance but change the repository's configuration. Their signatures have changed accordingly:

  • git_submodule_set_url(), git_submodule_set_ignore(), git_submodule_set_update(), git_submodule_set_fetch_recurse_submodules().

• git_submodule_status() no longer takes a submodule instance but a repsitory, a submodule name and an ignore setting.

• The push function in the git_transport interface now takes a pointer to the remote callbacks.

• The git_index_entry struct's fields' types have been changed to more accurately reflect what is in fact stored in the index. Specifically, time and file size are 32 bits intead of 64, as these values are truncated.

• GIT_EMERGECONFLICT is now GIT_ECONFLICT, which more accurately describes the nature of the error.

• It is no longer allowed to call git_buf_grow() on buffers borrowing the memory they point to.

v0.22

Changes or improvements

• git_signature_new() now requires a non-empty email address.

• Use CommonCrypto libraries for SHA-1 calculation on Mac OS X.

• Disable SSL compression and SSLv2 and SSLv3 ciphers in favor of TLSv1 in OpenSSL.

• The fetch behavior of remotes with autotag set to GIT_REMOTE_DOWNLOAD_TAGS_ALL has been changed to match git 1.9.0 and later. In this mode, libgit2 now fetches all tags in addition to whatever else needs to be fetched.

• git_checkout() now handles case-changing renames correctly on case-insensitive filesystems; for example renaming "readme" to "README".

• The search for libssh2 is now done via pkg-config instead of a custom search of a few directories.

• Add support for core.protectHFS and core.protectNTFS. Add more validation for filenames which we write such as references.

• The local transport now generates textual progress output like git-upload-pack does ("counting objects").

• git_checkout_index() can now check out an in-memory index that is not necessarily the repository's index, so you may check out an index that was produced by git_merge and friends while retaining the cached information.

• Remove the default timeout for receiving / sending data over HTTP using the WinHTTP transport layer.

• Add SPNEGO (Kerberos) authentication using GSSAPI on Unix systems.

• Provide built-in objects for the empty blob (e69de29) and empty tree (4b825dc) objects.

• The index' tree cache is now filled upon read-tree and write-tree and the cache is written to disk.

• LF -> CRLF filter refuses to handle mixed-EOL files

• LF -> CRLF filter now runs when * text = auto (with Git for Windows 1.9.4)

• File unlocks are atomic again via rename. Read-only files on Windows are made read-write if necessary.

• Share open packfiles across repositories to share descriptors and mmaps.

• Use a map for the treebuilder, making insertion O(1)

• The build system now accepts an option EMBED_SSH_PATH which when set tells it to include a copy of libssh2 at the given location. This is enabled for MSVC.

• Add support for refspecs with the asterisk in the middle of a pattern.

• Fetching now performs opportunistic updates. To achieve this, we introduce a difference between active and passive refspecs, which make git_remote_download() and git_remote_fetch() to take a list of resfpecs to be the active list, similarly to how git fetch accepts a list on the command-line.

• The THREADSAFE option to build libgit2 with threading support has been flipped to be on by default.

• The remote object has learnt to prune remote-tracking branches. If the remote is configured to do so, this will happen via git_remote_fetch(). You can also call git_remote_prune() after connecting or fetching to perform the prune.

API additions

• Introduce git_buf_text_is_binary() and git_buf_text_contains_nul() for consumers to perform binary detection on a git_buf.

• git_branch_upstream_remote() has been introduced to provide the branch..remote configuration value.

• Introduce git_describe_commit() and git_describe_workdir() to provide a description of the current commit (and working tree, respectively) based on the nearest tag or reference

• Introduce git_merge_bases() and the git_oidarray type to expose all merge bases between two commits.

• Introduce git_merge_bases_many() to expose all merge bases between multiple commits.

• Introduce rebase functionality (using the merge algorithm only). Introduce git_rebase_init() to begin a new rebase session, git_rebase_open() to open an in-progress rebase session, git_rebase_commit() to commit the current rebase operation, git_rebase_next() to apply the next rebase operation, git_rebase_abort() to abort an in-progress rebase and git_rebase_finish() to complete a rebase operation.

• Introduce git_note_author() and git_note_committer() to get the author and committer information on a git_note, respectively.

• A factory function for ssh has been added which allows to change the path of the programs to execute for receive-pack and upload-pack on the server, git_transport_ssh_with_paths().

• The ssh transport supports asking the remote host for accepted credential types as well as multiple challeges using a single connection. This requires to know which username you want to connect as, so this introduces the USERNAME credential type which the ssh transport will use to ask for the username.

• The GIT_EPEEL error code has been introduced when we cannot peel a tag to the requested object type; if the given object otherwise cannot be peeled, GIT_EINVALIDSPEC is returned.

• Introduce GIT_REPOSITORY_INIT_RELATIVE_GITLINK to use relative paths when writing gitlinks, as is used by git core for submodules.

• git_remote_prune() has been added. See above for description.

• Introduce reference transactions, which allow multiple references to be locked at the same time and updates be queued. This also allows us to safely update a reflog with arbitrary contents, as we need to do for stash.

API removals

• git_remote_supported_url() and git_remote_is_valid_url() have been removed as they have become essentially useless with rsync-style ssh paths.

• git_clone_into() and git_clone_local_into() have been removed from the public API in favour of git_clone callbacks.

• The option to ignore certificate errors via git_remote_cert_check() is no longer present. Instead, git_remote_callbacks has gained a new entry which lets the user perform their own certificate checks.

Breaking API changes

• git_cherry_pick() is now git_cherrypick().

• The git_submodule_update() function was renamed to git_submodule_update_strategy(). git_submodule_update() is now used to provide functionalty similar to "git submodule update".

• git_treebuilder_create() was renamed to git_treebuilder_new() to better reflect it being a constructor rather than something which writes to disk.

• git_treebuilder_new() (was git_treebuilder_create()) now takes a repository so that it can query repository configuration. Subsequently, git_treebuilder_write() no longer takes a repository.

• git_threads_init() and git_threads_shutdown() have been renamed to git_libgit2_init() and git_libgit2_shutdown() to better explain what their purpose is, as it's grown to be more than just about threads.

• git_libgit2_init() and git_libgit2_shutdown() now return the number of initializations of the library, so consumers may schedule work on the first initialization.

• The git_transport_register() function no longer takes a priority and takes a URL scheme name (eg "http") instead of a prefix like "http://"

• git_index_name_entrycount() and git_index_reuc_entrycount() now return size_t instead of unsigned int.

• The context_lines and interhunk_lines fields in git_diff_options are now uint32_t instead of uint16_t. This allows to set them to UINT_MAX, in effect asking for "infinite" context e.g. to iterate over all the unmodified lines of a diff.

• git_status_file() now takes an exact path. Use git_status_list_new() if pathspec searching is needed.

• git_note_create() has changed the position of the notes reference name to match git_note_remove().

• Rename git_remote_load() to git_remote_lookup() to bring it in line with the rest of the lookup functions.

• git_remote_rename() now takes the repository and the remote's current name. Accepting a remote indicates we want to change it, which we only did partially. It is much clearer if we accept a name and no loaded objects are changed.

• git_remote_delete() now accepts the repository and the remote's name instead of a loaded remote.

• git_merge_head is now git_annotated_commit, to better reflect its usage for multiple functions (including rebase)

• The git_clone_options struct no longer provides the ignore_cert_errors or remote_name members for remote customization.

  Instead, the git_clone_options struct has two new members, remote_cb and remote_cb_payload, which allow the caller to completely override the remote creation process. If needed, the caller can use this callback to give their remote a name other than the default (origin) or disable cert checking.

  The remote_callbacks member has been preserved for convenience, although it is not used when a remote creation callback is supplied.

• The git_clone_options struct now provides repository_cb and repository_cb_payload to allow the user to create a repository with custom options.

• The git_push struct to perform a push has been replaced with git_remote_upload(). The refspecs and options are passed as a function argument. git_push_update_tips() is now also git_remote_update_tips() and the callbacks are in the same struct as the rest.

• The git_remote_set_transport() function now sets a transport factory function, rather than a pre-existing transport instance.

• The git_transport structure definition has moved into the sys/transport.h file.

• libgit2 no longer automatically sets the OpenSSL locking functions. This is not something which we can know to do. A last-resort convenience function is provided in sys/openssl.h, git_openssl_set_locking() which can be used to set the locking.