19 files changed, 146 insertions, 41 deletions
diff --git a/Documentation/RelNotes/2.27.0.txt b/Documentation/RelNotes/2.27.0.txt
index e3121d0164..15518d06c1 100644
--- a/Documentation/RelNotes/2.27.0.txt
+++ b/Documentation/RelNotes/2.27.0.txt
@@ -24,6 +24,10 @@ Backward compatibility notes
    users may find annoying---those who prefer not to rebase need to
    set the variable to false to squelch the warning.
 
+ * The transport protocol version 2, which was promoted to the default
+   in Git 2.26 release, turned out to have some remaining rough edges,
+   so it has been demoted from the default.
+
 
 UI, Workflows & Features
 
@@ -178,6 +182,11 @@ Performance, Internal Implementation, Development Support etc.
    start_progress() and the stop_progress() calls as a "region" to be
    traced.
 
+ * Instead of downloading Windows SDK for CI jobs for windows builds
+   from an external site (wingit.blob.core.windows.net), use the one
+   created in the windows-build job, to work around quota issues at
+   the external site.
+
 
 Fixes since v2.26
 -----------------
@@ -470,6 +479,21 @@ Fixes since v2.26
    name.  This has been corrected.
    (merge 9068cfb20f rs/fsck-duplicate-names-in-trees later to maint).
 
+ * Code clean-up by removing a compatibility implementation of a
+   function we no longer use.
+   (merge 84b0115f0d cb/no-more-gmtime later to maint).
+
+ * When a binary file gets modified and renamed on both sides of history
+   to different locations, both files would be written to the working
+   tree but both would have the contents from "ours".  This has been
+   corrected so that the path from each side gets their original content.
+
+ * Fix for a copy-and-paste error introduced during 2.20 era.
+   (merge e68a5272b1 ds/multi-pack-verify later to maint).
+
+ * Update an unconditional use of "grep -a" with a perl script in a test.
+   (merge 1eb7371236 dd/t5703-grep-a-fix later to maint).
+
  * Other code cleanup, docfix, build fix, etc.
    (merge 564956f358 jc/maintain-doc later to maint).
    (merge 7422b2a0a1 sg/commit-slab-clarify-peek later to maint).
diff --git a/Documentation/RelNotes/2.28.0.txt b/Documentation/RelNotes/2.28.0.txt
new file mode 100644
index 0000000000..c386fc7158
--- /dev/null
+++ b/Documentation/RelNotes/2.28.0.txt
@@ -0,0 +1,52 @@
+Git 2.28 Release Notes
+======================
+
+Updates since v2.27
+-------------------
+
+Backward compatibility notes
+
+ * "feature.experimental" configuration variable is to let volunteers
+   easily opt into a set of newer features, which use of the v2
+   transport protocol is now a part of.
+
+
+UI, Workflows & Features
+
+ * The commands in the "diff" family learned to honor "diff.relative"
+   configuration variable.
+
+
+
+Performance, Internal Implementation, Development Support etc.
+
+ * Code optimization for a common case.
+   (merge 8777616e4d an/merge-single-strategy-optim later to maint).
+
+ * We've adopted a convention that any on-stack structure can be
+   initialized to have zero values in all fields with "= { 0 }",
+   even when the first field happens to be a pointer, but sparse
+   complained that a null pointer should be spelled NULL for a long
+   time.  Start using -Wno-universal-initializer option to squelch
+   it (the latest sparse has it on by default).
+
+
+
+Fixes since v2.27
+-----------------
+
+ * The "--prepare-p4-only" option of "git p4" is supposed to stop
+   after replaying one changeset, but kept going (by mistake?)
+
+ * The error message from "git checkout -b foo -t bar baz" was
+   confusing.
+
+ * Some repositories in the wild have commits that record nonsense
+   committer timezone (e.g. rails.git); "git fast-import" learned an
+   option to pass these nonsense timestamps intact to allow recreating
+   existing repositories as-is.
+   (merge d42a2fb72f en/fast-import-looser-date later to maint).
+
+ * Other code cleanup, docfix, build fix, etc.
+   (merge 2c31a7aa44 jx/pkt-line-doc-count-fix later to maint).
+   (merge d63ae31962 cb/t5608-cleanup later to maint).
diff --git a/Documentation/config/diff.txt b/Documentation/config/diff.txt
index ff09f1cf73..c3ae136eba 100644
--- a/Documentation/config/diff.txt
+++ b/Documentation/config/diff.txt
@@ -105,6 +105,10 @@ diff.mnemonicPrefix::
 diff.noprefix::
 	If set, 'git diff' does not show any source or destination prefix.
 
+diff.relative::
+	If set to 'true', 'git diff' does not show changes outside of the directory
+	and show pathnames relative to the current directory.
+
 diff.orderFile::
 	File indicating how to order files within a diff.
 	See the '-O' option to linkgit:git-diff[1] for details.
diff --git a/Documentation/config/feature.txt b/Documentation/config/feature.txt
index 4e3a5c0ceb..28c33602d5 100644
--- a/Documentation/config/feature.txt
+++ b/Documentation/config/feature.txt
@@ -22,6 +22,10 @@ existing commit-graph file(s). Occasionally, these files will merge and the
 write may take longer. Having an updated commit-graph file helps performance
 of many Git commands, including `git merge-base`, `git push -f`, and
 `git log --graph`.
++
+* `protocol.version=2` speeds up fetches from repositories with many refs by
+allowing the client to specify which refs to list before the server lists
+them.
 
 feature.manyFiles::
 	Enable config options that optimize for repos with many files in the
diff --git a/Documentation/config/protocol.txt b/Documentation/config/protocol.txt
index 0b40141613..c46e9b3d00 100644
--- a/Documentation/config/protocol.txt
+++ b/Documentation/config/protocol.txt
@@ -48,7 +48,8 @@ protocol.version::
 	If set, clients will attempt to communicate with a server
 	using the specified protocol version.  If the server does
 	not support it, communication falls back to version 0.
-	If unset, the default is `0`.
+	If unset, the default is `0`, unless `feature.experimental`
+	is enabled, in which case the default is `2`.
 	Supported versions:
 +
 --
diff --git a/Documentation/date-formats.txt b/Documentation/date-formats.txt
index 7e7eaba643..f1097fac69 100644
--- a/Documentation/date-formats.txt
+++ b/Documentation/date-formats.txt
@@ -22,8 +22,7 @@ ISO 8601::
 	`2005-04-07T22:13:13`. The parser accepts a space instead of the
 	`T` character as well. Fractional parts of a second will be ignored,
 	for example `2005-04-07T22:13:13.019` will be treated as
-	`2005-04-07T22:13:13`
-
+	`2005-04-07T22:13:13`.
 +
 NOTE: In addition, the date part is accepted in the following formats:
 `YYYY.MM.DD`, `MM/DD/YYYY` and `DD.MM.YYYY`.
diff --git a/Documentation/diff-options.txt b/Documentation/diff-options.txt
index bb31f0c42b..7987d72b02 100644
--- a/Documentation/diff-options.txt
+++ b/Documentation/diff-options.txt
@@ -643,15 +643,18 @@ ifndef::git-format-patch[]
 -R::
 	Swap two inputs; that is, show differences from index or
 	on-disk file to tree contents.
+endif::git-format-patch[]
 
 --relative[=<path>]::
+--no-relative::
 	When run from a subdirectory of the project, it can be
 	told to exclude changes outside the directory and show
 	pathnames relative to it with this option.  When you are
 	not in a subdirectory (e.g. in a bare repository), you
 	can name which subdirectory to make the output relative
 	to by giving a <path> as an argument.
-endif::git-format-patch[]
+	`--no-relative` can be used to countermand both `diff.relative` config
+	option and previous `--relative`.
 
 -a::
 --text::
diff --git a/Documentation/git-bugreport.txt b/Documentation/git-bugreport.txt
index 7fe9aef34e..66e88c2e31 100644
--- a/Documentation/git-bugreport.txt
+++ b/Documentation/git-bugreport.txt
@@ -29,6 +29,7 @@ The following information is captured automatically:
  - uname sysname, release, version, and machine strings
  - Compiler-specific info string
  - A list of enabled hooks
+ - $SHELL
 
 This tool is invoked via the typical Git setup process, which means that in some
 cases, it might not be able to launch - for example, if a relevant config file
@@ -46,7 +47,7 @@ OPTIONS
 --suffix <format>::
 	Specify an alternate suffix for the bugreport name, to create a file
 	named 'git-bugreport-<formatted suffix>'. This should take the form of a
-	link:strftime[3] format string; the current local time will be used.
+	strftime(3) format string; the current local time will be used.
 
 GIT
 ---
diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt
index 53a650225a..8ca1764d3d 100644
--- a/Documentation/git-commit-graph.txt
+++ b/Documentation/git-commit-graph.txt
@@ -47,8 +47,10 @@ with `--stdin-commits` or `--reachable`.)
 +
 With the `--stdin-commits` option, generate the new commit graph by
 walking commits starting at the commits specified in stdin as a list
-of OIDs in hex, one OID per line. (Cannot be combined with
-`--stdin-packs` or `--reachable`.)
+of OIDs in hex, one OID per line. OIDs that resolve to non-commits
+(either directly, or by peeling tags) are silently ignored. OIDs that
+are malformed, or do not exist generate an error. (Cannot be combined
+with `--stdin-packs` or `--reachable`.)
 +
 With the `--reachable` option, generate the new commit graph by walking
 commits starting at all refs. (Cannot be combined with `--stdin-commits`
@@ -58,7 +60,7 @@ With the `--append` option, include all commits that are present in the
 existing commit-graph file.
 +
 With the `--changed-paths` option, compute and write information about the
-paths changed between a commit and it's first parent. This operation can
+paths changed between a commit and its first parent. This operation can
 take a while on large repositories. It provides significant performance gains
 for getting history of a directory or a file with `git log -- <path>`.
 +
@@ -68,6 +70,7 @@ chain of multiple commit-graph files stored in
 strategy and other splitting options. The new commits not already in the
 commit-graph are added in a new "tip" file. This file is merged with the
 existing file if the following merge conditions are met:
++
 * If `--split=no-merge` is specified, a merge is never performed, and
 the remaining options are ignored. `--split=replace` overwrites the
 existing chain with a new one. A bare `--split` defers to the remaining
diff --git a/Documentation/git-credential.txt b/Documentation/git-credential.txt
index 8d990e92fd..31c81c4c02 100644
--- a/Documentation/git-credential.txt
+++ b/Documentation/git-credential.txt
@@ -151,11 +151,11 @@ Git understands the following attributes:
 	were read (e.g., `url=https://example.com` would behave as if
 	`protocol=https` and `host=example.com` had been provided). This
 	can help callers avoid parsing URLs themselves.
-
-	Note that specifying a protocol is mandatory and if the URL
-	doesn't specify a hostname (e.g., "cert:///path/to/file") the
-	credential will contain a hostname attribute whose value is an
-	empty string.
-
-	Components which are missing from the URL (e.g., there is no
-	username in the example above) will be left unset.
++
+Note that specifying a protocol is mandatory and if the URL
+doesn't specify a hostname (e.g., "cert:///path/to/file") the
+credential will contain a hostname attribute whose value is an
+empty string.
++
+Components which are missing from the URL (e.g., there is no
+username in the example above) will be left unset.
diff --git a/Documentation/git-fast-import.txt b/Documentation/git-fast-import.txt
index 77c6b3d001..7d9aad2a7e 100644
--- a/Documentation/git-fast-import.txt
+++ b/Documentation/git-fast-import.txt
@@ -293,7 +293,14 @@ by users who are located in the same location and time zone.  In this
 case a reasonable offset from UTC could be assumed.
 +
 Unlike the `rfc2822` format, this format is very strict.  Any
-variation in formatting will cause fast-import to reject the value.
+variation in formatting will cause fast-import to reject the value,
+and some sanity checks on the numeric values may also be performed.
+
+`raw-permissive`::
+	This is the same as `raw` except that no sanity checks on
+	the numeric epoch and local offset are performed.  This can
+	be useful when trying to filter or import an existing history
+	with e.g. bogus timezone values.
 
 `rfc2822`::
 	This is the standard email format as described by RFC 2822.
diff --git a/Documentation/git-sparse-checkout.txt b/Documentation/git-sparse-checkout.txt
index 1a3ace6082..7c8943af7a 100644
--- a/Documentation/git-sparse-checkout.txt
+++ b/Documentation/git-sparse-checkout.txt
@@ -70,7 +70,7 @@ C-style quoted strings.
 	`core.sparseCheckoutCone` is enabled, the given patterns are interpreted
 	as directory names as in the 'set' subcommand.
 
-'reapply::
+'reapply'::
 	Reapply the sparsity pattern rules to paths in the working tree.
 	Commands like merge or rebase can materialize paths to do their
 	work (e.g. in order to show you a conflict), and other
diff --git a/Documentation/git.txt b/Documentation/git.txt
index 9d6769e95a..12890841c4 100644
--- a/Documentation/git.txt
+++ b/Documentation/git.txt
@@ -493,7 +493,7 @@ double-quotes and respecting backslash escapes. E.g., the value
 	details. This variable has lower precedence than other path
 	variables such as GIT_INDEX_FILE, GIT_OBJECT_DIRECTORY...
 
-`GIT_DEFAULT_HASH_ALGORITHM`::
+`GIT_DEFAULT_HASH`::
 	If this variable is set, the default hash algorithm for new
 	repositories will be set to this value. This value is currently
 	ignored when cloning; the setting of the remote repository
diff --git a/Documentation/gitfaq.txt b/Documentation/gitfaq.txt
index 370d62dae4..9cd7a592ac 100644
--- a/Documentation/gitfaq.txt
+++ b/Documentation/gitfaq.txt
@@ -223,7 +223,7 @@ a file checked into the repository which is a template or set of defaults which
 can then be copied alongside and modified as appropriate.  This second, modified
 file is usually ignored to prevent accidentally committing it.
 
-[[files-in-.gitignore-are-tracked]]
+[[files-in-gitignore-are-tracked]]
 I asked Git to ignore various files, yet they are still tracked::
 	A `gitignore` file ensures that certain file(s) which are not
 	tracked by Git remain untracked.  However, sometimes particular
diff --git a/Documentation/gitremote-helpers.txt b/Documentation/gitremote-helpers.txt
index f48a031dc3..93baeeb029 100644
--- a/Documentation/gitremote-helpers.txt
+++ b/Documentation/gitremote-helpers.txt
@@ -405,7 +405,9 @@ Supported if the helper has the "connect" capability.
 	trying to fall back).  After line feed terminating the positive
 	(empty) response, the output of the service starts.  Messages
 	(both request and response) must consist of zero or more
-	PKT-LINEs, terminating in a flush packet. The client must not
+	PKT-LINEs, terminating in a flush packet. Response messages will
+	then have a response end packet after the flush packet to
+	indicate the end of a response.  The client must not
 	expect the server to store any state in between request-response
 	pairs.  After the connection ends, the remote helper exits.
 +
diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index 04ad7dd36e..b01b2b6773 100644
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -581,12 +581,12 @@ option does. Applied to the 'D..M' range, it results in:
 
 Before discussing another option, `--show-pulls`, we need to
 create a new example history.
-+
+
 A common problem users face when looking at simplified history is that a
 commit they know changed a file somehow does not appear in the file's
 simplified history. Let's demonstrate a new example and show how options
 such as `--full-history` and `--simplify-merges` works in that case:
-+
+
 -----------------------------------------------------------------------
 	  .-A---M-----C--N---O---P
 	 /     / \  \  \/   /   /
@@ -595,7 +595,7 @@ such as `--full-history` and `--simplify-merges` works in that case:
 	  \ /      /\        /
 	   `---X--'  `---Y--'
 -----------------------------------------------------------------------
-+
+
 For this example, suppose `I` created `file.txt` which was modified by
 `A`, `B`, and `X` in different ways. The single-parent commits `C`, `Z`,
 and `Y` do not change `file.txt`. The merge commit `M` was created by
@@ -607,19 +607,19 @@ the contents of `file.txt` at `X`. Hence, `R` is TREESAME to `X` but not
 contents of `file.txt` at `R`, so `N` is TREESAME to `R` but not `C`.
 The merge commits `O` and `P` are TREESAME to their first parents, but
 not to their second parents, `Z` and `Y` respectively.
-+
+
 When using the default mode, `N` and `R` both have a TREESAME parent, so
 those edges are walked and the others are ignored. The resulting history
 graph is:
-+
+
 -----------------------------------------------------------------------
 	I---X
 -----------------------------------------------------------------------
-+
+
 When using `--full-history`, Git walks every edge. This will discover
 the commits `A` and `B` and the merge `M`, but also will reveal the
 merge commits `O` and `P`. With parent rewriting, the resulting graph is:
-+
+
 -----------------------------------------------------------------------
 	  .-A---M--------N---O---P
 	 /     / \  \  \/   /   /
@@ -628,21 +628,21 @@ merge commits `O` and `P`. With parent rewriting, the resulting graph is:
 	  \ /      /\        /
 	   `---X--'  `------'
 -----------------------------------------------------------------------
-+
+
 Here, the merge commits `O` and `P` contribute extra noise, as they did
 not actually contribute a change to `file.txt`. They only merged a topic
 that was based on an older version of `file.txt`. This is a common
 issue in repositories using a workflow where many contributors work in
 parallel and merge their topic branches along a single trunk: manu
 unrelated merges appear in the `--full-history` results.
-+
+
 When using the `--simplify-merges` option, the commits `O` and `P`
 disappear from the results. This is because the rewritten second parents
 of `O` and `P` are reachable from their first parents. Those edges are
 removed and then the commits look like single-parent commits that are
 TREESAME to their parent. This also happens to the commit `N`, resulting
 in a history view as follows:
-+
+
 -----------------------------------------------------------------------
 	  .-A---M--.
 	 /     /    \
@@ -651,18 +651,18 @@ in a history view as follows:
 	  \ /      /
 	   `---X--'
 -----------------------------------------------------------------------
-+
+
 In this view, we see all of the important single-parent changes from
 `A`, `B`, and `X`. We also see the carefully-resolved merge `M` and the
 not-so-carefully-resolved merge `R`. This is usually enough information
 to determine why the commits `A` and `B` "disappeared" from history in
 the default view. However, there are a few issues with this approach.
-+
+
 The first issue is performance. Unlike any previous option, the
 `--simplify-merges` option requires walking the entire commit history
 before returning a single result. This can make the option difficult to
 use for very large repositories.
-+
+
 The second issue is one of auditing. When many contributors are working
 on the same repository, it is important which merge commits introduced
 a change into an important branch. The problematic merge `R` above is
@@ -671,10 +671,13 @@ important branch. Instead, the merge `N` was used to merge `R` and `X`
 into the important branch. This commit may have information about why
 the change `X` came to override the changes from `A` and `B` in its
 commit message.
+
+--show-pulls::
+	In addition to the commits shown in the default history, show
+	each merge commit that is not TREESAME to its first parent but
+	is TREESAME to a later parent.
 +
-The `--show-pulls` option helps with both of these issues by adding more
-merge commits to the history results. If a merge is not TREESAME to its
-first parent but is TREESAME to a later parent, then that merge is
+When a merge commit is included by `--show-pulls`, the merge is
 treated as if it "pulled" the change from another branch. When using
 `--show-pulls` on this example (and no other options) the resulting
 graph is:
diff --git a/Documentation/technical/http-protocol.txt b/Documentation/technical/http-protocol.txt
index 9c5b6f0fac..51a79e63de 100644
--- a/Documentation/technical/http-protocol.txt
+++ b/Documentation/technical/http-protocol.txt
@@ -216,7 +216,7 @@ smart server reply:
    S: 001e# service=git-upload-pack\n
    S: 0000
    S: 004895dcfa3633004da0049d3d0fa03f80589cbcaf31 refs/heads/maint\0multi_ack\n
-   S: 0042d049f6c27a2244e12041955e262a404c7faba355 refs/heads/master\n
+   S: 003fd049f6c27a2244e12041955e262a404c7faba355 refs/heads/master\n
    S: 003c2cb58b79488a98d2721cea644875a8dd0026b115 refs/tags/v1.0\n
    S: 003fa3c2e2402b99163d1d59756e5f207ae21cccba4c refs/tags/v1.0^{}\n
    S: 0000
diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index d5ce4eea8a..a4573d12ce 100644
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -96,7 +96,7 @@ 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" |
+     "003agit-upload-pack /schacon/gitbook.git\0host=example.com\0" |
      nc -v example.com 9418
 
 
@@ -171,9 +171,9 @@ 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" |
+   $ echo -e -n "0045git-upload-pack /schacon/gitbook.git\0host=example.com\0\0version=1\0" |
       nc -v example.com 9418
-   000aversion 1
+   000eversion 1
    00887217a7c7e582c46cec22a130adf4b9d7d950fba0 HEAD\0multi_ack thin-pack
 		side-band side-band-64k ofs-delta shallow no-progress include-tag
    00441d3fcd5ced445d1abc402225c0b8a1299641f497 refs/heads/integration
diff --git a/Documentation/technical/protocol-v2.txt b/Documentation/technical/protocol-v2.txt
index 7e3766cafb..3996d70891 100644
--- a/Documentation/technical/protocol-v2.txt
+++ b/Documentation/technical/protocol-v2.txt
@@ -33,6 +33,8 @@ In protocol v2 these special packets will have the following semantics:
 
   * '0000' Flush Packet (flush-pkt) - indicates the end of a message
   * '0001' Delimiter Packet (delim-pkt) - separates sections of a message
+  * '0002' Message Packet (response-end-pkt) - indicates the end of a response
+    for stateless connections
 
 Initial Client Request
 ----------------------