diff mbox series

[4/5] fsmonitor: use IPC to query the builtin FSMonitor daemon

Message ID f2e5da9e5c622d9142baafee47c3e1cdffbef666.1631822063.git.gitgitgadget@gmail.com (mailing list archive)
State Superseded
Headers show
Series Builtin FSMonitor Part 2 | expand

Commit Message

Jeff Hostetler Sept. 16, 2021, 7:54 p.m. UTC
From: Jeff Hostetler <jeffhost@microsoft.com>

Use simple IPC to directly communicate with the new builtin file
system monitor daemon when `core.useBuiltinFSMonitor` is set.

The `core.fsmonitor` setting has already been defined as a HOOK
pathname.  Historically, this has been set to a HOOK script that will
talk with Watchman.  For compatibility reasons, we do not want to
overload that definition (and cause problems if users have multiple
versions of Git installed).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
---
 fsmonitor.c | 34 ++++++++++++++++++++++++++++++++--
 1 file changed, 32 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/fsmonitor.c b/fsmonitor.c
index 63174630c0e..695fb0ce4e7 100644
--- a/fsmonitor.c
+++ b/fsmonitor.c
@@ -254,8 +254,37 @@  void refresh_fsmonitor(struct index_state *istate)
 	trace_printf_key(&trace_fsmonitor, "refresh fsmonitor");
 
 	if (fsm_mode == FSMONITOR_MODE_IPC) {
-		/* TODO */
-		return;
+		query_success = !fsmonitor_ipc__send_query(
+			istate->fsmonitor_last_update ?
+			istate->fsmonitor_last_update : "builtin:fake",
+			&query_result);
+		if (query_success) {
+			/*
+			 * The response contains a series of nul terminated
+			 * strings.  The first is the new token.
+			 *
+			 * Use `char *buf` as an interlude to trick the CI
+			 * static analysis to let us use `strbuf_addstr()`
+			 * here (and only copy the token) rather than
+			 * `strbuf_addbuf()`.
+			 */
+			buf = query_result.buf;
+			strbuf_addstr(&last_update_token, buf);
+			bol = last_update_token.len + 1;
+		} else {
+			/*
+			 * The builtin daemon is not available on this
+			 * platform -OR- we failed to get a response.
+			 *
+			 * Generate a fake token (rather than a V1
+			 * timestamp) for the index extension.  (If
+			 * they switch back to the hook API, we don't
+			 * want ambiguous state.)
+			 */
+			strbuf_addstr(&last_update_token, "builtin:fake");
+		}
+
+		goto apply_results;
 	}
 
 	assert(fsm_mode == FSMONITOR_MODE_HOOK);
@@ -321,6 +350,7 @@  void refresh_fsmonitor(struct index_state *istate)
 				 query_success ? "success" : "failure");
 	}
 
+apply_results:
 	/*
 	 * The response from FSMonitor (excluding the header token) is
 	 * either: