Re: [PATCH 8/8] read-cache: inform the daemon that the index has been updated

> The daemon would immediately load the new index in memory in
> background. Next time Git needs to read the index again, everything is
> ready.
>
> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
> ---
>  cache.h      |  1 +
>  read-cache.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++-----
>  2 files changed, 49 insertions(+), 5 deletions(-)
>
> diff --git a/cache.h b/cache.h
> index fb29c7e..3115b86 100644
> --- a/cache.h
> +++ b/cache.h
> @@ -483,6 +483,7 @@ extern int is_index_unborn(struct index_state *);
>  extern int read_index_unmerged(struct index_state *);
>  #define COMMIT_LOCK            (1 << 0)
>  #define CLOSE_LOCK             (1 << 1)
> +#define REFRESH_DAEMON         (1 << 2)
>  extern int write_locked_index(struct index_state *, struct lock_file *lock, unsigned flags);
>  extern int discard_index(struct index_state *);
>  extern int unmerged_index(const struct index_state *);
> diff --git a/read-cache.c b/read-cache.c
> index e98521f..d5c9247 100644
> --- a/read-cache.c
> +++ b/read-cache.c
> @@ -16,6 +16,9 @@
>  #include "varint.h"
>  #include "split-index.h"
>  #include "sigchain.h"
> +#include "unix-socket.h"
> +#include "pkt-line.h"
> +#include "run-command.h"
>
>  static struct cache_entry *refresh_cache_entry(struct cache_entry *ce,
>                                                unsigned int options);
> @@ -2030,6 +2033,32 @@ void set_alternate_index_output(const char *name)
>         alternate_index_output = name;
>  }
>
> +static void refresh_daemon(struct index_state *istate)
> +{
> +       int fd;
> +       fd = unix_stream_connect(git_path("daemon/index"));
> +       if (fd < 0) {
> +               struct child_process cp;
> +               const char *av[] = {"read-cache--daemon", "--detach", NULL };
> +               memset(&cp, 0, sizeof(cp));
> +               cp.argv = av;
> +               cp.git_cmd = 1;
> +               cp.no_stdin = 1;
> +               if (run_command(&cp))
> +                       warning(_("failed to start read-cache--daemon: %s"),
> +                               strerror(errno));
> +               return;
> +       }
> +       /*
> +        * packet_write() could die() but unless this is from
> +        * update_index_if_able(), we're about to exit anyway,
> +        * probably ok to die (for now). Blocking mode is another
> +        * problem to deal with later.
> +        */
> +       packet_write(fd, "refresh");
> +       close(fd);
> +}
> +