git/fsmonitor-ipc.c
Jeff Hostetler d2bd862e7a fsmonitor-ipc: create client routines for git-fsmonitor--daemon
Create fsmonitor_ipc__*() client routines to spawn the built-in file
system monitor daemon and send it an IPC request using the `Simple
IPC` API.

Stub in empty fsmonitor_ipc__*() functions for unsupported platforms.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-25 16:04:15 -07:00

172 lines
3.8 KiB
C

#include "cache.h"
#include "fsmonitor.h"
#include "simple-ipc.h"
#include "fsmonitor-ipc.h"
#include "run-command.h"
#include "strbuf.h"
#include "trace2.h"
#ifndef HAVE_FSMONITOR_DAEMON_BACKEND
/*
* A trivial implementation of the fsmonitor_ipc__ API for unsupported
* platforms.
*/
int fsmonitor_ipc__is_supported(void)
{
return 0;
}
const char *fsmonitor_ipc__get_path(void)
{
return NULL;
}
enum ipc_active_state fsmonitor_ipc__get_state(void)
{
return IPC_STATE__OTHER_ERROR;
}
int fsmonitor_ipc__send_query(const char *since_token,
struct strbuf *answer)
{
return -1;
}
int fsmonitor_ipc__send_command(const char *command,
struct strbuf *answer)
{
return -1;
}
#else
int fsmonitor_ipc__is_supported(void)
{
return 1;
}
GIT_PATH_FUNC(fsmonitor_ipc__get_path, "fsmonitor--daemon.ipc")
enum ipc_active_state fsmonitor_ipc__get_state(void)
{
return ipc_get_active_state(fsmonitor_ipc__get_path());
}
static int spawn_daemon(void)
{
const char *args[] = { "fsmonitor--daemon", "start", NULL };
return run_command_v_opt_tr2(args, RUN_COMMAND_NO_STDIN | RUN_GIT_CMD,
"fsmonitor");
}
int fsmonitor_ipc__send_query(const char *since_token,
struct strbuf *answer)
{
int ret = -1;
int tried_to_spawn = 0;
enum ipc_active_state state = IPC_STATE__OTHER_ERROR;
struct ipc_client_connection *connection = NULL;
struct ipc_client_connect_options options
= IPC_CLIENT_CONNECT_OPTIONS_INIT;
const char *tok = since_token ? since_token : "";
size_t tok_len = since_token ? strlen(since_token) : 0;
options.wait_if_busy = 1;
options.wait_if_not_found = 0;
trace2_region_enter("fsm_client", "query", NULL);
trace2_data_string("fsm_client", NULL, "query/command", tok);
try_again:
state = ipc_client_try_connect(fsmonitor_ipc__get_path(), &options,
&connection);
switch (state) {
case IPC_STATE__LISTENING:
ret = ipc_client_send_command_to_connection(
connection, tok, tok_len, answer);
ipc_client_close_connection(connection);
trace2_data_intmax("fsm_client", NULL,
"query/response-length", answer->len);
goto done;
case IPC_STATE__NOT_LISTENING:
case IPC_STATE__PATH_NOT_FOUND:
if (tried_to_spawn)
goto done;
tried_to_spawn++;
if (spawn_daemon())
goto done;
/*
* Try again, but this time give the daemon a chance to
* actually create the pipe/socket.
*
* Granted, the daemon just started so it can't possibly have
* any FS cached yet, so we'll always get a trivial answer.
* BUT the answer should include a new token that can serve
* as the basis for subsequent requests.
*/
options.wait_if_not_found = 1;
goto try_again;
case IPC_STATE__INVALID_PATH:
ret = error(_("fsmonitor_ipc__send_query: invalid path '%s'"),
fsmonitor_ipc__get_path());
goto done;
case IPC_STATE__OTHER_ERROR:
default:
ret = error(_("fsmonitor_ipc__send_query: unspecified error on '%s'"),
fsmonitor_ipc__get_path());
goto done;
}
done:
trace2_region_leave("fsm_client", "query", NULL);
return ret;
}
int fsmonitor_ipc__send_command(const char *command,
struct strbuf *answer)
{
struct ipc_client_connection *connection = NULL;
struct ipc_client_connect_options options
= IPC_CLIENT_CONNECT_OPTIONS_INIT;
int ret;
enum ipc_active_state state;
const char *c = command ? command : "";
size_t c_len = command ? strlen(command) : 0;
strbuf_reset(answer);
options.wait_if_busy = 1;
options.wait_if_not_found = 0;
state = ipc_client_try_connect(fsmonitor_ipc__get_path(), &options,
&connection);
if (state != IPC_STATE__LISTENING) {
die(_("fsmonitor--daemon is not running"));
return -1;
}
ret = ipc_client_send_command_to_connection(connection, c, c_len,
answer);
ipc_client_close_connection(connection);
if (ret == -1) {
die(_("could not send '%s' command to fsmonitor--daemon"), c);
return -1;
}
return 0;
}
#endif