merge(third_party/git): Merge squashed git subtree at v2.23.0 r/373

Merge commit '1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5' as 'third_party/git'

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+Packfile transfer protocols
+===========================
+
+Git supports transferring data in packfiles over the ssh://, git://, http:// and
+file:// transports.  There exist two sets of protocols, one for pushing
+data from a client to a server and another for fetching data from a
+server to a client.  The three transports (ssh, git, file) use the same
+protocol to transfer data. http is documented in http-protocol.txt.
+
+The processes invoked in the canonical Git implementation are 'upload-pack'
+on the server side and 'fetch-pack' on the client side for fetching data;
+then 'receive-pack' on the server and 'send-pack' on the client for pushing
+data.  The protocol functions to have a server tell a client what is
+currently on the server, then for the two to negotiate the smallest amount
+of data to send in order to fully update one or the other.
+
+pkt-line Format
+---------------
+
+The descriptions below build on the pkt-line format described in
+protocol-common.txt. When the grammar indicate `PKT-LINE(...)`, unless
+otherwise noted the usual pkt-line LF rules apply: the sender SHOULD
+include a LF, but the receiver MUST NOT complain if it is not present.
+
+An error packet is a special pkt-line that contains an error string.
+
+----
+  error-line     =  PKT-LINE("ERR" SP explanation-text)
+----
+
+Throughout the protocol, where `PKT-LINE(...)` is expected, an error packet MAY
+be sent. Once this packet is sent by a client or a server, the data transfer
+process defined in this protocol is terminated.
+
+Transports
+----------
+There are three transports over which the packfile protocol is
+initiated.  The Git transport is a simple, unauthenticated server that
+takes the command (almost always 'upload-pack', though Git
+servers can be configured to be globally writable, in which 'receive-
+pack' initiation is also allowed) with which the client wishes to
+communicate and executes it and connects it to the requesting
+process.
+
+In the SSH transport, the client just runs the 'upload-pack'
+or 'receive-pack' process on the server over the SSH protocol and then
+communicates with that invoked process over the SSH connection.
+
+The file:// transport runs the 'upload-pack' or 'receive-pack'
+process locally and communicates with it over a pipe.
+
+Extra Parameters
+----------------
+
+The protocol provides a mechanism in which clients can send additional
+information in its first message to the server. These are called "Extra
+Parameters", and are supported by the Git, SSH, and HTTP protocols.
+
+Each Extra Parameter takes the form of `<key>=<value>` or `<key>`.
+
+Servers that receive any such Extra Parameters MUST ignore all
+unrecognized keys. Currently, the only Extra Parameter recognized is
+"version" with a value of '1' or '2'.  See protocol-v2.txt for more
+information on protocol version 2.
+
+Git Transport
+-------------
+
+The Git transport starts off by sending the command and repository
+on the wire using the pkt-line format, followed by a NUL byte and a
+hostname parameter, terminated by a NUL byte.
+
+   0033git-upload-pack /project.git\0host=myserver.com\0
+
+The transport may send Extra Parameters by adding an additional NUL
+byte, and then adding one or more NUL-terminated strings:
+
+   003egit-upload-pack /project.git\0host=myserver.com\0\0version=1\0
+
+--
+   git-proto-request = request-command SP pathname NUL
+		       [ host-parameter NUL ] [ NUL extra-parameters ]
+   request-command   = "git-upload-pack" / "git-receive-pack" /
+		       "git-upload-archive"   ; case sensitive
+   pathname          = *( %x01-ff ) ; exclude NUL
+   host-parameter    = "host=" hostname [ ":" port ]
+   extra-parameters  = 1*extra-parameter
+   extra-parameter   = 1*( %x01-ff ) NUL
+--
+
+host-parameter is used for the
+git-daemon name based virtual hosting.  See --interpolated-path
+option to git daemon, with the %H/%CH format characters.
+
+Basically what the Git client is doing to connect to an 'upload-pack'
+process on the server side over the Git protocol is this:
+
+   $ echo -e -n \
+     "0039git-upload-pack /schacon/gitbook.git\0host=example.com\0" |
+     nc -v example.com 9418
+
+
+SSH Transport
+-------------
+
+Initiating the upload-pack or receive-pack processes over SSH is
+executing the binary on the server via SSH remote execution.
+It is basically equivalent to running this:
+
+   $ ssh git.example.com "git-upload-pack '/project.git'"
+
+For a server to support Git pushing and pulling for a given user over
+SSH, that user needs to be able to execute one or both of those
+commands via the SSH shell that they are provided on login.  On some
+systems, that shell access is limited to only being able to run those
+two commands, or even just one of them.
+
+In an ssh:// format URI, it's absolute in the URI, so the '/' after
+the host name (or port number) is sent as an argument, which is then
+read by the remote git-upload-pack exactly as is, so it's effectively
+an absolute path in the remote filesystem.
+
+       git clone ssh://user@example.com/project.git
+		    |
+		    v
+    ssh user@example.com "git-upload-pack '/project.git'"
+
+In a "user@host:path" format URI, its relative to the user's home
+directory, because the Git client will run:
+
+     git clone user@example.com:project.git
+		    |
+		    v
+  ssh user@example.com "git-upload-pack 'project.git'"
+
+The exception is if a '~' is used, in which case
+we execute it without the leading '/'.
+
+      ssh://user@example.com/~alice/project.git,
+		     |
+		     v
+   ssh user@example.com "git-upload-pack '~alice/project.git'"
+
+Depending on the value of the `protocol.version` configuration variable,
+Git may attempt to send Extra Parameters as a colon-separated string in
+the GIT_PROTOCOL environment variable. This is done only if
+the `ssh.variant` configuration variable indicates that the ssh command
+supports passing environment variables as an argument.
+
+A few things to remember here:
+
+- The "command name" is spelled with dash (e.g. git-upload-pack), but
+  this can be overridden by the client;
+
+- The repository path is always quoted with single quotes.
+
+Fetching Data From a Server
+---------------------------
+
+When one Git repository wants to get data that a second repository
+has, the first can 'fetch' from the second.  This operation determines
+what data the server has that the client does not then streams that
+data down to the client in packfile format.
+
+
+Reference Discovery
+-------------------
+
+When the client initially connects the server will immediately respond
+with a version number (if "version=1" is sent as an Extra Parameter),
+and a listing of each reference it has (all branches and tags) along
+with the object name that each reference currently points to.
+
+   $ echo -e -n "0044git-upload-pack /schacon/gitbook.git\0host=example.com\0\0version=1\0" |
+      nc -v example.com 9418
+   000aversion 1
+   00887217a7c7e582c46cec22a130adf4b9d7d950fba0 HEAD\0multi_ack thin-pack
+		side-band side-band-64k ofs-delta shallow no-progress include-tag
+   00441d3fcd5ced445d1abc402225c0b8a1299641f497 refs/heads/integration
+   003f7217a7c7e582c46cec22a130adf4b9d7d950fba0 refs/heads/master
+   003cb88d2441cac0977faf98efc80305012112238d9d refs/tags/v0.9
+   003c525128480b96c89e6418b1e40909bf6c5b2d580f refs/tags/v1.0
+   003fe92df48743b7bc7d26bcaabfddde0a1e20cae47c refs/tags/v1.0^{}
+   0000
+
+The returned response is a pkt-line stream describing each ref and
+its current value.  The stream MUST be sorted by name according to
+the C locale ordering.
+
+If HEAD is a valid ref, HEAD MUST appear as the first advertised
+ref.  If HEAD is not a valid ref, HEAD MUST NOT appear in the
+advertisement list at all, but other refs may still appear.
+
+The stream MUST include capability declarations behind a NUL on the
+first ref. The peeled value of a ref (that is "ref^{}") MUST be
+immediately after the ref itself, if presented. A conforming server
+MUST peel the ref if it's an annotated tag.
+
+----
+  advertised-refs  =  *1("version 1")
+		      (no-refs / list-of-refs)
+		      *shallow
+		      flush-pkt
+
+  no-refs          =  PKT-LINE(zero-id SP "capabilities^{}"
+		      NUL capability-list)
+
+  list-of-refs     =  first-ref *other-ref
+  first-ref        =  PKT-LINE(obj-id SP refname
+		      NUL capability-list)
+
+  other-ref        =  PKT-LINE(other-tip / other-peeled)
+  other-tip        =  obj-id SP refname
+  other-peeled     =  obj-id SP refname "^{}"
+
+  shallow          =  PKT-LINE("shallow" SP obj-id)
+
+  capability-list  =  capability *(SP capability)
+  capability       =  1*(LC_ALPHA / DIGIT / "-" / "_")
+  LC_ALPHA         =  %x61-7A
+----
+
+Server and client MUST use lowercase for obj-id, both MUST treat obj-id
+as case-insensitive.
+
+See protocol-capabilities.txt for a list of allowed server capabilities
+and descriptions.
+
+Packfile Negotiation
+--------------------
+After reference and capabilities discovery, the client can decide to
+terminate the connection by sending a flush-pkt, telling the server it can
+now gracefully terminate, and disconnect, when it does not need any pack
+data. This can happen with the ls-remote command, and also can happen when
+the client already is up to date.
+
+Otherwise, it enters the negotiation phase, where the client and
+server determine what the minimal packfile necessary for transport is,
+by telling the server what objects it wants, its shallow objects
+(if any), and the maximum commit depth it wants (if any).  The client
+will also send a list of the capabilities it wants to be in effect,
+out of what the server said it could do with the first 'want' line.
+
+----
+  upload-request    =  want-list
+		       *shallow-line
+		       *1depth-request
+		       [filter-request]
+		       flush-pkt
+
+  want-list         =  first-want
+		       *additional-want
+
+  shallow-line      =  PKT-LINE("shallow" SP obj-id)
+
+  depth-request     =  PKT-LINE("deepen" SP depth) /
+		       PKT-LINE("deepen-since" SP timestamp) /
+		       PKT-LINE("deepen-not" SP ref)
+
+  first-want        =  PKT-LINE("want" SP obj-id SP capability-list)
+  additional-want   =  PKT-LINE("want" SP obj-id)
+
+  depth             =  1*DIGIT
+
+  filter-request    =  PKT-LINE("filter" SP filter-spec)
+----
+
+Clients MUST send all the obj-ids it wants from the reference
+discovery phase as 'want' lines. Clients MUST send at least one
+'want' command in the request body. Clients MUST NOT mention an
+obj-id in a 'want' command which did not appear in the response
+obtained through ref discovery.
+
+The client MUST write all obj-ids which it only has shallow copies
+of (meaning that it does not have the parents of a commit) as
+'shallow' lines so that the server is aware of the limitations of
+the client's history.
+
+The client now sends the maximum commit history depth it wants for
+this transaction, which is the number of commits it wants from the
+tip of the history, if any, as a 'deepen' line.  A depth of 0 is the
+same as not making a depth request. The client does not want to receive
+any commits beyond this depth, nor does it want objects needed only to
+complete those commits. Commits whose parents are not received as a
+result are defined as shallow and marked as such in the server. This
+information is sent back to the client in the next step.
+
+The client can optionally request that pack-objects omit various
+objects from the packfile using one of several filtering techniques.
+These are intended for use with partial clone and partial fetch
+operations. An object that does not meet a filter-spec value is
+omitted unless explicitly requested in a 'want' line. See `rev-list`
+for possible filter-spec values.
+
+Once all the 'want's and 'shallow's (and optional 'deepen') are
+transferred, clients MUST send a flush-pkt, to tell the server side
+that it is done sending the list.
+
+Otherwise, if the client sent a positive depth request, the server
+will determine which commits will and will not be shallow and
+send this information to the client. If the client did not request
+a positive depth, this step is skipped.
+
+----
+  shallow-update   =  *shallow-line
+		      *unshallow-line
+		      flush-pkt
+
+  shallow-line     =  PKT-LINE("shallow" SP obj-id)
+
+  unshallow-line   =  PKT-LINE("unshallow" SP obj-id)
+----
+
+If the client has requested a positive depth, the server will compute
+the set of commits which are no deeper than the desired depth. The set
+of commits start at the client's wants.
+
+The server writes 'shallow' lines for each
+commit whose parents will not be sent as a result. The server writes
+an 'unshallow' line for each commit which the client has indicated is
+shallow, but is no longer shallow at the currently requested depth
+(that is, its parents will now be sent). The server MUST NOT mark
+as unshallow anything which the client has not indicated was shallow.
+
+Now the client will send a list of the obj-ids it has using 'have'
+lines, so the server can make a packfile that only contains the objects
+that the client needs. In multi_ack mode, the canonical implementation
+will send up to 32 of these at a time, then will send a flush-pkt. The
+canonical implementation will skip ahead and send the next 32 immediately,
+so that there is always a block of 32 "in-flight on the wire" at a time.
+
+----
+  upload-haves      =  have-list
+		       compute-end
+
+  have-list         =  *have-line
+  have-line         =  PKT-LINE("have" SP obj-id)
+  compute-end       =  flush-pkt / PKT-LINE("done")
+----
+
+If the server reads 'have' lines, it then will respond by ACKing any
+of the obj-ids the client said it had that the server also has. The
+server will ACK obj-ids differently depending on which ack mode is
+chosen by the client.
+
+In multi_ack mode:
+
+  * the server will respond with 'ACK obj-id continue' for any common
+    commits.
+
+  * once the server has found an acceptable common base commit and is
+    ready to make a packfile, it will blindly ACK all 'have' obj-ids
+    back to the client.
+
+  * the server will then send a 'NAK' and then wait for another response
+    from the client - either a 'done' or another list of 'have' lines.
+
+In multi_ack_detailed mode:
+
+  * the server will differentiate the ACKs where it is signaling
+    that it is ready to send data with 'ACK obj-id ready' lines, and
+    signals the identified common commits with 'ACK obj-id common' lines.
+
+Without either multi_ack or multi_ack_detailed:
+
+ * upload-pack sends "ACK obj-id" on the first common object it finds.
+   After that it says nothing until the client gives it a "done".
+
+ * upload-pack sends "NAK" on a flush-pkt if no common object
+   has been found yet.  If one has been found, and thus an ACK
+   was already sent, it's silent on the flush-pkt.
+
+After the client has gotten enough ACK responses that it can determine
+that the server has enough information to send an efficient packfile
+(in the canonical implementation, this is determined when it has received
+enough ACKs that it can color everything left in the --date-order queue
+as common with the server, or the --date-order queue is empty), or the
+client determines that it wants to give up (in the canonical implementation,
+this is determined when the client sends 256 'have' lines without getting
+any of them ACKed by the server - meaning there is nothing in common and
+the server should just send all of its objects), then the client will send
+a 'done' command.  The 'done' command signals to the server that the client
+is ready to receive its packfile data.
+
+However, the 256 limit *only* turns on in the canonical client
+implementation if we have received at least one "ACK %s continue"
+during a prior round.  This helps to ensure that at least one common
+ancestor is found before we give up entirely.
+
+Once the 'done' line is read from the client, the server will either
+send a final 'ACK obj-id' or it will send a 'NAK'. 'obj-id' is the object
+name of the last commit determined to be common. The server only sends
+ACK after 'done' if there is at least one common base and multi_ack or
+multi_ack_detailed is enabled. The server always sends NAK after 'done'
+if there is no common base found.
+
+Instead of 'ACK' or 'NAK', the server may send an error message (for
+example, if it does not recognize an object in a 'want' line received
+from the client).
+
+Then the server will start sending its packfile data.
+
+----
+  server-response = *ack_multi ack / nak
+  ack_multi       = PKT-LINE("ACK" SP obj-id ack_status)
+  ack_status      = "continue" / "common" / "ready"
+  ack             = PKT-LINE("ACK" SP obj-id)
+  nak             = PKT-LINE("NAK")
+----
+
+A simple clone may look like this (with no 'have' lines):
+
+----
+   C: 0054want 74730d410fcb6603ace96f1dc55ea6196122532d multi_ack \
+     side-band-64k ofs-delta\n
+   C: 0032want 7d1665144a3a975c05f1f43902ddaf084e784dbe\n
+   C: 0032want 5a3f6be755bbb7deae50065988cbfa1ffa9ab68a\n
+   C: 0032want 7e47fe2bd8d01d481f44d7af0531bd93d3b21c01\n
+   C: 0032want 74730d410fcb6603ace96f1dc55ea6196122532d\n
+   C: 0000
+   C: 0009done\n
+
+   S: 0008NAK\n
+   S: [PACKFILE]
+----
+
+An incremental update (fetch) response might look like this:
+
+----
+   C: 0054want 74730d410fcb6603ace96f1dc55ea6196122532d multi_ack \
+     side-band-64k ofs-delta\n
+   C: 0032want 7d1665144a3a975c05f1f43902ddaf084e784dbe\n
+   C: 0032want 5a3f6be755bbb7deae50065988cbfa1ffa9ab68a\n
+   C: 0000
+   C: 0032have 7e47fe2bd8d01d481f44d7af0531bd93d3b21c01\n
+   C: [30 more have lines]
+   C: 0032have 74730d410fcb6603ace96f1dc55ea6196122532d\n
+   C: 0000
+
+   S: 003aACK 7e47fe2bd8d01d481f44d7af0531bd93d3b21c01 continue\n
+   S: 003aACK 74730d410fcb6603ace96f1dc55ea6196122532d continue\n
+   S: 0008NAK\n
+
+   C: 0009done\n
+
+   S: 0031ACK 74730d410fcb6603ace96f1dc55ea6196122532d\n
+   S: [PACKFILE]
+----
+
+
+Packfile Data
+-------------
+
+Now that the client and server have finished negotiation about what
+the minimal amount of data that needs to be sent to the client is, the server
+will construct and send the required data in packfile format.
+
+See pack-format.txt for what the packfile itself actually looks like.
+
+If 'side-band' or 'side-band-64k' capabilities have been specified by
+the client, the server will send the packfile data multiplexed.
+
+Each packet starting with the packet-line length of the amount of data
+that follows, followed by a single byte specifying the sideband the
+following data is coming in on.
+
+In 'side-band' mode, it will send up to 999 data bytes plus 1 control
+code, for a total of up to 1000 bytes in a pkt-line.  In 'side-band-64k'
+mode it will send up to 65519 data bytes plus 1 control code, for a
+total of up to 65520 bytes in a pkt-line.
+
+The sideband byte will be a '1', '2' or a '3'. Sideband '1' will contain
+packfile data, sideband '2' will be used for progress information that the
+client will generally print to stderr and sideband '3' is used for error
+information.
+
+If no 'side-band' capability was specified, the server will stream the
+entire packfile without multiplexing.
+
+
+Pushing Data To a Server
+------------------------
+
+Pushing data to a server will invoke the 'receive-pack' process on the
+server, which will allow the client to tell it which references it should
+update and then send all the data the server will need for those new
+references to be complete.  Once all the data is received and validated,
+the server will then update its references to what the client specified.
+
+Authentication
+--------------
+
+The protocol itself contains no authentication mechanisms.  That is to be
+handled by the transport, such as SSH, before the 'receive-pack' process is
+invoked.  If 'receive-pack' is configured over the Git transport, those
+repositories will be writable by anyone who can access that port (9418) as
+that transport is unauthenticated.
+
+Reference Discovery
+-------------------
+
+The reference discovery phase is done nearly the same way as it is in the
+fetching protocol. Each reference obj-id and name on the server is sent
+in packet-line format to the client, followed by a flush-pkt.  The only
+real difference is that the capability listing is different - the only
+possible values are 'report-status', 'delete-refs', 'ofs-delta' and
+'push-options'.
+
+Reference Update Request and Packfile Transfer
+----------------------------------------------
+
+Once the client knows what references the server is at, it can send a
+list of reference update requests.  For each reference on the server
+that it wants to update, it sends a line listing the obj-id currently on
+the server, the obj-id the client would like to update it to and the name
+of the reference.
+
+This list is followed by a flush-pkt.
+
+----
+  update-requests   =  *shallow ( command-list | push-cert )
+
+  shallow           =  PKT-LINE("shallow" SP obj-id)
+
+  command-list      =  PKT-LINE(command NUL capability-list)
+		       *PKT-LINE(command)
+		       flush-pkt
+
+  command           =  create / delete / update
+  create            =  zero-id SP new-id  SP name
+  delete            =  old-id  SP zero-id SP name
+  update            =  old-id  SP new-id  SP name
+
+  old-id            =  obj-id
+  new-id            =  obj-id
+
+  push-cert         = PKT-LINE("push-cert" NUL capability-list LF)
+		      PKT-LINE("certificate version 0.1" LF)
+		      PKT-LINE("pusher" SP ident LF)
+		      PKT-LINE("pushee" SP url LF)
+		      PKT-LINE("nonce" SP nonce LF)
+		      *PKT-LINE("push-option" SP push-option LF)
+		      PKT-LINE(LF)
+		      *PKT-LINE(command LF)
+		      *PKT-LINE(gpg-signature-lines LF)
+		      PKT-LINE("push-cert-end" LF)
+
+  push-option       =  1*( VCHAR | SP )
+----
+
+If the server has advertised the 'push-options' capability and the client has
+specified 'push-options' as part of the capability list above, the client then
+sends its push options followed by a flush-pkt.
+
+----
+  push-options      =  *PKT-LINE(push-option) flush-pkt
+----
+
+For backwards compatibility with older Git servers, if the client sends a push
+cert and push options, it MUST send its push options both embedded within the
+push cert and after the push cert. (Note that the push options within the cert
+are prefixed, but the push options after the cert are not.) Both these lists
+MUST be the same, modulo the prefix.
+
+After that the packfile that
+should contain all the objects that the server will need to complete the new
+references will be sent.
+
+----
+  packfile          =  "PACK" 28*(OCTET)
+----
+
+If the receiving end does not support delete-refs, the sending end MUST
+NOT ask for delete command.
+
+If the receiving end does not support push-cert, the sending end
+MUST NOT send a push-cert command.  When a push-cert command is
+sent, command-list MUST NOT be sent; the commands recorded in the
+push certificate is used instead.
+
+The packfile MUST NOT be sent if the only command used is 'delete'.
+
+A packfile MUST be sent if either create or update command is used,
+even if the server already has all the necessary objects.  In this
+case the client MUST send an empty packfile.   The only time this
+is likely to happen is if the client is creating
+a new branch or a tag that points to an existing obj-id.
+
+The server will receive the packfile, unpack it, then validate each
+reference that is being updated that it hasn't changed while the request
+was being processed (the obj-id is still the same as the old-id), and
+it will run any update hooks to make sure that the update is acceptable.
+If all of that is fine, the server will then update the references.
+
+Push Certificate
+----------------
+
+A push certificate begins with a set of header lines.  After the
+header and an empty line, the protocol commands follow, one per
+line. Note that the trailing LF in push-cert PKT-LINEs is _not_
+optional; it must be present.
+
+Currently, the following header fields are defined:
+
+`pusher` ident::
+	Identify the GPG key in "Human Readable Name <email@address>"
+	format.
+
+`pushee` url::
+	The repository URL (anonymized, if the URL contains
+	authentication material) the user who ran `git push`
+	intended to push into.
+
+`nonce` nonce::
+	The 'nonce' string the receiving repository asked the
+	pushing user to include in the certificate, to prevent
+	replay attacks.
+
+The GPG signature lines are a detached signature for the contents
+recorded in the push certificate before the signature block begins.
+The detached signature is used to certify that the commands were
+given by the pusher, who must be the signer.
+
+Report Status
+-------------
+
+After receiving the pack data from the sender, the receiver sends a
+report if 'report-status' capability is in effect.
+It is a short listing of what happened in that update.  It will first
+list the status of the packfile unpacking as either 'unpack ok' or
+'unpack [error]'.  Then it will list the status for each of the references
+that it tried to update.  Each line is either 'ok [refname]' if the
+update was successful, or 'ng [refname] [error]' if the update was not.
+
+----
+  report-status     = unpack-status
+		      1*(command-status)
+		      flush-pkt
+
+  unpack-status     = PKT-LINE("unpack" SP unpack-result)
+  unpack-result     = "ok" / error-msg
+
+  command-status    = command-ok / command-fail
+  command-ok        = PKT-LINE("ok" SP refname)
+  command-fail      = PKT-LINE("ng" SP refname SP error-msg)
+
+  error-msg         = 1*(OCTECT) ; where not "ok"
+----
+
+Updates can be unsuccessful for a number of reasons.  The reference can have
+changed since the reference discovery phase was originally sent, meaning
+someone pushed in the meantime.  The reference being pushed could be a
+non-fast-forward reference and the update hooks or configuration could be
+set to not allow that, etc.  Also, some references can be updated while others
+can be rejected.
+
+An example client/server communication might look like this:
+
+----
+   S: 006274730d410fcb6603ace96f1dc55ea6196122532d refs/heads/local\0report-status delete-refs ofs-delta\n
+   S: 003e7d1665144a3a975c05f1f43902ddaf084e784dbe refs/heads/debug\n
+   S: 003f74730d410fcb6603ace96f1dc55ea6196122532d refs/heads/master\n
+   S: 003d74730d410fcb6603ace96f1dc55ea6196122532d refs/heads/team\n
+   S: 0000
+
+   C: 00677d1665144a3a975c05f1f43902ddaf084e784dbe 74730d410fcb6603ace96f1dc55ea6196122532d refs/heads/debug\n
+   C: 006874730d410fcb6603ace96f1dc55ea6196122532d 5a3f6be755bbb7deae50065988cbfa1ffa9ab68a refs/heads/master\n
+   C: 0000
+   C: [PACKDATA]
+
+   S: 000eunpack ok\n
+   S: 0018ok refs/heads/debug\n
+   S: 002ang refs/heads/master non-fast-forward\n
+----