Here is Part 2 of my Builtin FSMonitor series. Part 2 requires
jh/builtin-fsmonitor-part1 be present.

Part 2 contains:

 * Client-side code to connect to a (yet to be developed) FSMonitor daemon
   over simple IPC (using Named Pipes or Unix Domain Sockets).
 * Updated config settings to allow the client to decide whether to use
   Simple IPC or the existing FSMonitor Hook API.

The original FSMonitor feature "e05336bdda (Merge branch 'bp/fsmonitor',
2017-11-21)" consisted of two parts:

 1. Client code: 1.1. Called by commands like git status 1.2. Uses the Hook
    API to spawn and talk to a shell or perl script (usually) 1.3. Receives
    a list of recently modified files and/or directories 1.4. Updates flags
    and/or loops in various algorithms to avoid unnecessary lstat() calls on
    unchanged ones.

 2. Hook code: 2.1. A hook process, spawned by each client command, talks to
    a long-running FS monitoring process. 2.2. A long-running FS monitoring
    process, usually Watchman. 2.3. The hook process acts as a relay to
    translate requests responses from Watchman back to the client command.

The Builtin FSMonitor feature extends step 1.2 and allows clients to
communicate directly with a FS daemon process using Simple IPC. The daemon
response is then processed as before in step 1.3.

Part 2 contains these client-side changes for IPC. A builtin FSMonitor
daemon will be added in a later patch series.

Jeff Hostetler (5):
  fsmonitor: enhance existing comments
  fsmonitor-ipc: create client routines for git-fsmonitor--daemon
  fsmonitor: config settings are repository-specific
  fsmonitor: use IPC to query the builtin FSMonitor daemon
  fsmonitor: update fsmonitor config documentation

 Documentation/config/core.txt      |  56 ++++++---
 Documentation/git-update-index.txt |  27 +++--
 Documentation/githooks.txt         |   3 +-
 Makefile                           |   2 +
 builtin/update-index.c             |  19 +++-
 cache.h                            |   1 -
 config.c                           |  14 ---
 config.h                           |   1 -
 environment.c                      |   1 -
 fsmonitor-ipc.c                    | 176 +++++++++++++++++++++++++++++
 fsmonitor-ipc.h                    |  48 ++++++++
 fsmonitor-settings.c               |  97 ++++++++++++++++
 fsmonitor-settings.h               |  21 ++++
 fsmonitor.c                        | 130 +++++++++++++++------
 fsmonitor.h                        |  18 ++-
 repo-settings.c                    |   2 +
 repository.h                       |   3 +
 t/README                           |   4 +-
 18 files changed, 538 insertions(+), 85 deletions(-)
 create mode 100644 fsmonitor-ipc.c
 create mode 100644 fsmonitor-ipc.h
 create mode 100644 fsmonitor-settings.c
 create mode 100644 fsmonitor-settings.h

base-commit: 8b7c11b8668b4e774f81a9f0b4c30144b818f1d1

Submitted-As: https://lore.kernel.org/git/pull.1041.git.1631822063.gitgitgadget@gmail.com