summaryrefslogtreecommitdiffstats
path: root/compat/simple-ipc/ipc-win32.c
diff options
context:
space:
mode:
Diffstat (limited to 'compat/simple-ipc/ipc-win32.c')
-rw-r--r--compat/simple-ipc/ipc-win32.c900
1 files changed, 900 insertions, 0 deletions
diff --git a/compat/simple-ipc/ipc-win32.c b/compat/simple-ipc/ipc-win32.c
new file mode 100644
index 0000000..20ea7b6
--- /dev/null
+++ b/compat/simple-ipc/ipc-win32.c
@@ -0,0 +1,900 @@
+#include "cache.h"
+#include "simple-ipc.h"
+#include "strbuf.h"
+#include "pkt-line.h"
+#include "thread-utils.h"
+#include "accctrl.h"
+#include "aclapi.h"
+
+#ifndef SUPPORTS_SIMPLE_IPC
+/*
+ * This source file should only be compiled when Simple IPC is supported.
+ * See the top-level Makefile.
+ */
+#error SUPPORTS_SIMPLE_IPC not defined
+#endif
+
+static int initialize_pipe_name(const char *path, wchar_t *wpath, size_t alloc)
+{
+ int off = 0;
+ struct strbuf realpath = STRBUF_INIT;
+
+ if (!strbuf_realpath(&realpath, path, 0))
+ return -1;
+
+ off = swprintf(wpath, alloc, L"\\\\.\\pipe\\");
+ if (xutftowcs(wpath + off, realpath.buf, alloc - off) < 0)
+ return -1;
+
+ /* Handle drive prefix */
+ if (wpath[off] && wpath[off + 1] == L':') {
+ wpath[off + 1] = L'_';
+ off += 2;
+ }
+
+ for (; wpath[off]; off++)
+ if (wpath[off] == L'/')
+ wpath[off] = L'\\';
+
+ strbuf_release(&realpath);
+ return 0;
+}
+
+static enum ipc_active_state get_active_state(wchar_t *pipe_path)
+{
+ if (WaitNamedPipeW(pipe_path, NMPWAIT_USE_DEFAULT_WAIT))
+ return IPC_STATE__LISTENING;
+
+ if (GetLastError() == ERROR_SEM_TIMEOUT)
+ return IPC_STATE__NOT_LISTENING;
+
+ if (GetLastError() == ERROR_FILE_NOT_FOUND)
+ return IPC_STATE__PATH_NOT_FOUND;
+
+ trace2_data_intmax("ipc-debug", NULL, "getstate/waitpipe/gle",
+ (intmax_t)GetLastError());
+
+ return IPC_STATE__OTHER_ERROR;
+}
+
+enum ipc_active_state ipc_get_active_state(const char *path)
+{
+ wchar_t pipe_path[MAX_PATH];
+
+ if (initialize_pipe_name(path, pipe_path, ARRAY_SIZE(pipe_path)) < 0)
+ return IPC_STATE__INVALID_PATH;
+
+ return get_active_state(pipe_path);
+}
+
+#define WAIT_STEP_MS (50)
+
+static enum ipc_active_state connect_to_server(
+ const wchar_t *wpath,
+ DWORD timeout_ms,
+ const struct ipc_client_connect_options *options,
+ int *pfd)
+{
+ DWORD t_start_ms, t_waited_ms;
+ DWORD step_ms;
+ HANDLE hPipe = INVALID_HANDLE_VALUE;
+ DWORD mode = PIPE_READMODE_BYTE;
+ DWORD gle;
+
+ *pfd = -1;
+
+ for (;;) {
+ hPipe = CreateFileW(wpath, GENERIC_READ | GENERIC_WRITE,
+ 0, NULL, OPEN_EXISTING, 0, NULL);
+ if (hPipe != INVALID_HANDLE_VALUE)
+ break;
+
+ gle = GetLastError();
+
+ switch (gle) {
+ case ERROR_FILE_NOT_FOUND:
+ if (!options->wait_if_not_found)
+ return IPC_STATE__PATH_NOT_FOUND;
+ if (!timeout_ms)
+ return IPC_STATE__PATH_NOT_FOUND;
+
+ step_ms = (timeout_ms < WAIT_STEP_MS) ?
+ timeout_ms : WAIT_STEP_MS;
+ sleep_millisec(step_ms);
+
+ timeout_ms -= step_ms;
+ break; /* try again */
+
+ case ERROR_PIPE_BUSY:
+ if (!options->wait_if_busy)
+ return IPC_STATE__NOT_LISTENING;
+ if (!timeout_ms)
+ return IPC_STATE__NOT_LISTENING;
+
+ t_start_ms = (DWORD)(getnanotime() / 1000000);
+
+ if (!WaitNamedPipeW(wpath, timeout_ms)) {
+ DWORD gleWait = GetLastError();
+
+ if (gleWait == ERROR_SEM_TIMEOUT)
+ return IPC_STATE__NOT_LISTENING;
+
+ trace2_data_intmax("ipc-debug", NULL,
+ "connect/waitpipe/gle",
+ (intmax_t)gleWait);
+
+ return IPC_STATE__OTHER_ERROR;
+ }
+
+ /*
+ * A pipe server instance became available.
+ * Race other client processes to connect to
+ * it.
+ *
+ * But first decrement our overall timeout so
+ * that we don't starve if we keep losing the
+ * race. But also guard against special
+ * NPMWAIT_ values (0 and -1).
+ */
+ t_waited_ms = (DWORD)(getnanotime() / 1000000) - t_start_ms;
+ if (t_waited_ms < timeout_ms)
+ timeout_ms -= t_waited_ms;
+ else
+ timeout_ms = 1;
+ break; /* try again */
+
+ default:
+ trace2_data_intmax("ipc-debug", NULL,
+ "connect/createfile/gle",
+ (intmax_t)gle);
+
+ return IPC_STATE__OTHER_ERROR;
+ }
+ }
+
+ if (!SetNamedPipeHandleState(hPipe, &mode, NULL, NULL)) {
+ gle = GetLastError();
+ trace2_data_intmax("ipc-debug", NULL,
+ "connect/setpipestate/gle",
+ (intmax_t)gle);
+
+ CloseHandle(hPipe);
+ return IPC_STATE__OTHER_ERROR;
+ }
+
+ *pfd = _open_osfhandle((intptr_t)hPipe, O_RDWR|O_BINARY);
+ if (*pfd < 0) {
+ gle = GetLastError();
+ trace2_data_intmax("ipc-debug", NULL,
+ "connect/openosfhandle/gle",
+ (intmax_t)gle);
+
+ CloseHandle(hPipe);
+ return IPC_STATE__OTHER_ERROR;
+ }
+
+ /* fd now owns hPipe */
+
+ return IPC_STATE__LISTENING;
+}
+
+/*
+ * The default connection timeout for Windows clients.
+ *
+ * This is not currently part of the ipc_ API (nor the config settings)
+ * because of differences between Windows and other platforms.
+ *
+ * This value was chosen at random.
+ */
+#define WINDOWS_CONNECTION_TIMEOUT_MS (30000)
+
+enum ipc_active_state ipc_client_try_connect(
+ const char *path,
+ const struct ipc_client_connect_options *options,
+ struct ipc_client_connection **p_connection)
+{
+ wchar_t wpath[MAX_PATH];
+ enum ipc_active_state state = IPC_STATE__OTHER_ERROR;
+ int fd = -1;
+
+ *p_connection = NULL;
+
+ trace2_region_enter("ipc-client", "try-connect", NULL);
+ trace2_data_string("ipc-client", NULL, "try-connect/path", path);
+
+ if (initialize_pipe_name(path, wpath, ARRAY_SIZE(wpath)) < 0)
+ state = IPC_STATE__INVALID_PATH;
+ else
+ state = connect_to_server(wpath, WINDOWS_CONNECTION_TIMEOUT_MS,
+ options, &fd);
+
+ trace2_data_intmax("ipc-client", NULL, "try-connect/state",
+ (intmax_t)state);
+ trace2_region_leave("ipc-client", "try-connect", NULL);
+
+ if (state == IPC_STATE__LISTENING) {
+ (*p_connection) = xcalloc(1, sizeof(struct ipc_client_connection));
+ (*p_connection)->fd = fd;
+ }
+
+ return state;
+}
+
+void ipc_client_close_connection(struct ipc_client_connection *connection)
+{
+ if (!connection)
+ return;
+
+ if (connection->fd != -1)
+ close(connection->fd);
+
+ free(connection);
+}
+
+int ipc_client_send_command_to_connection(
+ struct ipc_client_connection *connection,
+ const char *message, size_t message_len,
+ struct strbuf *answer)
+{
+ int ret = 0;
+
+ strbuf_setlen(answer, 0);
+
+ trace2_region_enter("ipc-client", "send-command", NULL);
+
+ if (write_packetized_from_buf_no_flush(message, message_len,
+ connection->fd) < 0 ||
+ packet_flush_gently(connection->fd) < 0) {
+ ret = error(_("could not send IPC command"));
+ goto done;
+ }
+
+ FlushFileBuffers((HANDLE)_get_osfhandle(connection->fd));
+
+ if (read_packetized_to_strbuf(
+ connection->fd, answer,
+ PACKET_READ_GENTLE_ON_EOF | PACKET_READ_GENTLE_ON_READ_ERROR) < 0) {
+ ret = error(_("could not read IPC response"));
+ goto done;
+ }
+
+done:
+ trace2_region_leave("ipc-client", "send-command", NULL);
+ return ret;
+}
+
+int ipc_client_send_command(const char *path,
+ const struct ipc_client_connect_options *options,
+ const char *message, size_t message_len,
+ struct strbuf *response)
+{
+ int ret = -1;
+ enum ipc_active_state state;
+ struct ipc_client_connection *connection = NULL;
+
+ state = ipc_client_try_connect(path, options, &connection);
+
+ if (state != IPC_STATE__LISTENING)
+ return ret;
+
+ ret = ipc_client_send_command_to_connection(connection,
+ message, message_len,
+ response);
+
+ ipc_client_close_connection(connection);
+
+ return ret;
+}
+
+/*
+ * Duplicate the given pipe handle and wrap it in a file descriptor so
+ * that we can use pkt-line on it.
+ */
+static int dup_fd_from_pipe(const HANDLE pipe)
+{
+ HANDLE process = GetCurrentProcess();
+ HANDLE handle;
+ int fd;
+
+ if (!DuplicateHandle(process, pipe, process, &handle, 0, FALSE,
+ DUPLICATE_SAME_ACCESS)) {
+ errno = err_win_to_posix(GetLastError());
+ return -1;
+ }
+
+ fd = _open_osfhandle((intptr_t)handle, O_RDWR|O_BINARY);
+ if (fd < 0) {
+ errno = err_win_to_posix(GetLastError());
+ CloseHandle(handle);
+ return -1;
+ }
+
+ /*
+ * `handle` is now owned by `fd` and will be automatically closed
+ * when the descriptor is closed.
+ */
+
+ return fd;
+}
+
+/*
+ * Magic numbers used to annotate callback instance data.
+ * These are used to help guard against accidentally passing the
+ * wrong instance data across multiple levels of callbacks (which
+ * is easy to do if there are `void*` arguments).
+ */
+enum magic {
+ MAGIC_SERVER_REPLY_DATA,
+ MAGIC_SERVER_THREAD_DATA,
+ MAGIC_SERVER_DATA,
+};
+
+struct ipc_server_reply_data {
+ enum magic magic;
+ int fd;
+ struct ipc_server_thread_data *server_thread_data;
+};
+
+struct ipc_server_thread_data {
+ enum magic magic;
+ struct ipc_server_thread_data *next_thread;
+ struct ipc_server_data *server_data;
+ pthread_t pthread_id;
+ HANDLE hPipe;
+};
+
+/*
+ * On Windows, the conceptual "ipc-server" is implemented as a pool of
+ * n idential/peer "server-thread" threads. That is, there is no
+ * hierarchy of threads; and therefore no controller thread managing
+ * the pool. Each thread has an independent handle to the named pipe,
+ * receives incoming connections, processes the client, and re-uses
+ * the pipe for the next client connection.
+ *
+ * Therefore, the "ipc-server" only needs to maintain a list of the
+ * spawned threads for eventual "join" purposes.
+ *
+ * A single "stop-event" is visible to all of the server threads to
+ * tell them to shutdown (when idle).
+ */
+struct ipc_server_data {
+ enum magic magic;
+ ipc_server_application_cb *application_cb;
+ void *application_data;
+ struct strbuf buf_path;
+ wchar_t wpath[MAX_PATH];
+
+ HANDLE hEventStopRequested;
+ struct ipc_server_thread_data *thread_list;
+ int is_stopped;
+};
+
+enum connect_result {
+ CR_CONNECTED = 0,
+ CR_CONNECT_PENDING,
+ CR_CONNECT_ERROR,
+ CR_WAIT_ERROR,
+ CR_SHUTDOWN,
+};
+
+static enum connect_result queue_overlapped_connect(
+ struct ipc_server_thread_data *server_thread_data,
+ OVERLAPPED *lpo)
+{
+ if (ConnectNamedPipe(server_thread_data->hPipe, lpo))
+ goto failed;
+
+ switch (GetLastError()) {
+ case ERROR_IO_PENDING:
+ return CR_CONNECT_PENDING;
+
+ case ERROR_PIPE_CONNECTED:
+ SetEvent(lpo->hEvent);
+ return CR_CONNECTED;
+
+ default:
+ break;
+ }
+
+failed:
+ error(_("ConnectNamedPipe failed for '%s' (%lu)"),
+ server_thread_data->server_data->buf_path.buf,
+ GetLastError());
+ return CR_CONNECT_ERROR;
+}
+
+/*
+ * Use Windows Overlapped IO to wait for a connection or for our event
+ * to be signalled.
+ */
+static enum connect_result wait_for_connection(
+ struct ipc_server_thread_data *server_thread_data,
+ OVERLAPPED *lpo)
+{
+ enum connect_result r;
+ HANDLE waitHandles[2];
+ DWORD dwWaitResult;
+
+ r = queue_overlapped_connect(server_thread_data, lpo);
+ if (r != CR_CONNECT_PENDING)
+ return r;
+
+ waitHandles[0] = server_thread_data->server_data->hEventStopRequested;
+ waitHandles[1] = lpo->hEvent;
+
+ dwWaitResult = WaitForMultipleObjects(2, waitHandles, FALSE, INFINITE);
+ switch (dwWaitResult) {
+ case WAIT_OBJECT_0 + 0:
+ return CR_SHUTDOWN;
+
+ case WAIT_OBJECT_0 + 1:
+ ResetEvent(lpo->hEvent);
+ return CR_CONNECTED;
+
+ default:
+ return CR_WAIT_ERROR;
+ }
+}
+
+/*
+ * Forward declare our reply callback function so that any compiler
+ * errors are reported when we actually define the function (in addition
+ * to any errors reported when we try to pass this callback function as
+ * a parameter in a function call). The former are easier to understand.
+ */
+static ipc_server_reply_cb do_io_reply_callback;
+
+/*
+ * Relay application's response message to the client process.
+ * (We do not flush at this point because we allow the caller
+ * to chunk data to the client thru us.)
+ */
+static int do_io_reply_callback(struct ipc_server_reply_data *reply_data,
+ const char *response, size_t response_len)
+{
+ if (reply_data->magic != MAGIC_SERVER_REPLY_DATA)
+ BUG("reply_cb called with wrong instance data");
+
+ return write_packetized_from_buf_no_flush(response, response_len,
+ reply_data->fd);
+}
+
+/*
+ * Receive the request/command from the client and pass it to the
+ * registered request-callback. The request-callback will compose
+ * a response and call our reply-callback to send it to the client.
+ *
+ * Simple-IPC only contains one round trip, so we flush and close
+ * here after the response.
+ */
+static int do_io(struct ipc_server_thread_data *server_thread_data)
+{
+ struct strbuf buf = STRBUF_INIT;
+ struct ipc_server_reply_data reply_data;
+ int ret = 0;
+
+ reply_data.magic = MAGIC_SERVER_REPLY_DATA;
+ reply_data.server_thread_data = server_thread_data;
+
+ reply_data.fd = dup_fd_from_pipe(server_thread_data->hPipe);
+ if (reply_data.fd < 0)
+ return error(_("could not create fd from pipe for '%s'"),
+ server_thread_data->server_data->buf_path.buf);
+
+ ret = read_packetized_to_strbuf(
+ reply_data.fd, &buf,
+ PACKET_READ_GENTLE_ON_EOF | PACKET_READ_GENTLE_ON_READ_ERROR);
+ if (ret >= 0) {
+ ret = server_thread_data->server_data->application_cb(
+ server_thread_data->server_data->application_data,
+ buf.buf, buf.len, do_io_reply_callback, &reply_data);
+
+ packet_flush_gently(reply_data.fd);
+
+ FlushFileBuffers((HANDLE)_get_osfhandle((reply_data.fd)));
+ }
+ else {
+ /*
+ * The client probably disconnected/shutdown before it
+ * could send a well-formed message. Ignore it.
+ */
+ }
+
+ strbuf_release(&buf);
+ close(reply_data.fd);
+
+ return ret;
+}
+
+/*
+ * Handle IPC request and response with this connected client. And reset
+ * the pipe to prepare for the next client.
+ */
+static int use_connection(struct ipc_server_thread_data *server_thread_data)
+{
+ int ret;
+
+ ret = do_io(server_thread_data);
+
+ FlushFileBuffers(server_thread_data->hPipe);
+ DisconnectNamedPipe(server_thread_data->hPipe);
+
+ return ret;
+}
+
+/*
+ * Thread proc for an IPC server worker thread. It handles a series of
+ * connections from clients. It cleans and reuses the hPipe between each
+ * client.
+ */
+static void *server_thread_proc(void *_server_thread_data)
+{
+ struct ipc_server_thread_data *server_thread_data = _server_thread_data;
+ HANDLE hEventConnected = INVALID_HANDLE_VALUE;
+ OVERLAPPED oConnect;
+ enum connect_result cr;
+ int ret;
+
+ assert(server_thread_data->hPipe != INVALID_HANDLE_VALUE);
+
+ trace2_thread_start("ipc-server");
+ trace2_data_string("ipc-server", NULL, "pipe",
+ server_thread_data->server_data->buf_path.buf);
+
+ hEventConnected = CreateEventW(NULL, TRUE, FALSE, NULL);
+
+ memset(&oConnect, 0, sizeof(oConnect));
+ oConnect.hEvent = hEventConnected;
+
+ for (;;) {
+ cr = wait_for_connection(server_thread_data, &oConnect);
+
+ switch (cr) {
+ case CR_SHUTDOWN:
+ goto finished;
+
+ case CR_CONNECTED:
+ ret = use_connection(server_thread_data);
+ if (ret == SIMPLE_IPC_QUIT) {
+ ipc_server_stop_async(
+ server_thread_data->server_data);
+ goto finished;
+ }
+ if (ret > 0) {
+ /*
+ * Ignore (transient) IO errors with this
+ * client and reset for the next client.
+ */
+ }
+ break;
+
+ case CR_CONNECT_PENDING:
+ /* By construction, this should not happen. */
+ BUG("ipc-server[%s]: unexpeced CR_CONNECT_PENDING",
+ server_thread_data->server_data->buf_path.buf);
+
+ case CR_CONNECT_ERROR:
+ case CR_WAIT_ERROR:
+ /*
+ * Ignore these theoretical errors.
+ */
+ DisconnectNamedPipe(server_thread_data->hPipe);
+ break;
+
+ default:
+ BUG("unandled case after wait_for_connection");
+ }
+ }
+
+finished:
+ CloseHandle(server_thread_data->hPipe);
+ CloseHandle(hEventConnected);
+
+ trace2_thread_exit();
+ return NULL;
+}
+
+/*
+ * We need to build a Windows "SECURITY_ATTRIBUTES" object and use it
+ * to apply an ACL when we create the initial instance of the Named
+ * Pipe. The construction is somewhat involved and consists of
+ * several sequential steps and intermediate objects.
+ *
+ * We use this structure to hold these intermediate pointers so that
+ * we can free them as a group. (It is unclear from the docs whether
+ * some of these intermediate pointers can be freed before we are
+ * finished using the "lpSA" member.)
+ */
+struct my_sa_data
+{
+ PSID pEveryoneSID;
+ PACL pACL;
+ PSECURITY_DESCRIPTOR pSD;
+ LPSECURITY_ATTRIBUTES lpSA;
+};
+
+static void init_sa(struct my_sa_data *d)
+{
+ memset(d, 0, sizeof(*d));
+}
+
+static void release_sa(struct my_sa_data *d)
+{
+ if (d->pEveryoneSID)
+ FreeSid(d->pEveryoneSID);
+ if (d->pACL)
+ LocalFree(d->pACL);
+ if (d->pSD)
+ LocalFree(d->pSD);
+ if (d->lpSA)
+ LocalFree(d->lpSA);
+
+ memset(d, 0, sizeof(*d));
+}
+
+/*
+ * Create SECURITY_ATTRIBUTES to apply to the initial named pipe. The
+ * creator of the first server instance gets to set the ACLs on it.
+ *
+ * We allow the well-known group `EVERYONE` to have read+write access
+ * to the named pipe so that clients can send queries to the daemon
+ * and receive the response.
+ *
+ * Normally, this is not necessary since the daemon is usually
+ * automatically started by a foreground command like `git status`,
+ * but in those cases where an elevated Git command started the daemon
+ * (such that the daemon itself runs with elevation), we need to add
+ * the ACL so that non-elevated commands can write to it.
+ *
+ * The following document was helpful:
+ * https://docs.microsoft.com/en-us/windows/win32/secauthz/creating-a-security-descriptor-for-a-new-object-in-c--
+ *
+ * Returns d->lpSA set to a SA or NULL.
+ */
+static LPSECURITY_ATTRIBUTES get_sa(struct my_sa_data *d)
+{
+ SID_IDENTIFIER_AUTHORITY sid_auth_world = SECURITY_WORLD_SID_AUTHORITY;
+#define NR_EA (1)
+ EXPLICIT_ACCESS ea[NR_EA];
+ DWORD dwResult;
+
+ if (!AllocateAndInitializeSid(&sid_auth_world, 1,
+ SECURITY_WORLD_RID, 0,0,0,0,0,0,0,
+ &d->pEveryoneSID)) {
+ DWORD gle = GetLastError();
+ trace2_data_intmax("ipc-debug", NULL, "alloc-world-sid/gle",
+ (intmax_t)gle);
+ goto fail;
+ }
+
+ memset(ea, 0, NR_EA * sizeof(EXPLICIT_ACCESS));
+
+ ea[0].grfAccessPermissions = GENERIC_READ | GENERIC_WRITE;
+ ea[0].grfAccessMode = SET_ACCESS;
+ ea[0].grfInheritance = NO_INHERITANCE;
+ ea[0].Trustee.MultipleTrusteeOperation = NO_MULTIPLE_TRUSTEE;
+ ea[0].Trustee.TrusteeForm = TRUSTEE_IS_SID;
+ ea[0].Trustee.TrusteeType = TRUSTEE_IS_WELL_KNOWN_GROUP;
+ ea[0].Trustee.ptstrName = (LPTSTR)d->pEveryoneSID;
+
+ dwResult = SetEntriesInAcl(NR_EA, ea, NULL, &d->pACL);
+ if (dwResult != ERROR_SUCCESS) {
+ DWORD gle = GetLastError();
+ trace2_data_intmax("ipc-debug", NULL, "set-acl-entry/gle",
+ (intmax_t)gle);
+ trace2_data_intmax("ipc-debug", NULL, "set-acl-entry/dw",
+ (intmax_t)dwResult);
+ goto fail;
+ }
+
+ d->pSD = (PSECURITY_DESCRIPTOR)LocalAlloc(
+ LPTR, SECURITY_DESCRIPTOR_MIN_LENGTH);
+ if (!InitializeSecurityDescriptor(d->pSD, SECURITY_DESCRIPTOR_REVISION)) {
+ DWORD gle = GetLastError();
+ trace2_data_intmax("ipc-debug", NULL, "init-sd/gle", (intmax_t)gle);
+ goto fail;
+ }
+
+ if (!SetSecurityDescriptorDacl(d->pSD, TRUE, d->pACL, FALSE)) {
+ DWORD gle = GetLastError();
+ trace2_data_intmax("ipc-debug", NULL, "set-sd-dacl/gle", (intmax_t)gle);
+ goto fail;
+ }
+
+ d->lpSA = (LPSECURITY_ATTRIBUTES)LocalAlloc(LPTR, sizeof(SECURITY_ATTRIBUTES));
+ d->lpSA->nLength = sizeof(SECURITY_ATTRIBUTES);
+ d->lpSA->lpSecurityDescriptor = d->pSD;
+ d->lpSA->bInheritHandle = FALSE;
+
+ return d->lpSA;
+
+fail:
+ release_sa(d);
+ return NULL;
+}
+
+static HANDLE create_new_pipe(wchar_t *wpath, int is_first)
+{
+ HANDLE hPipe;
+ DWORD dwOpenMode, dwPipeMode;
+ struct my_sa_data my_sa_data;
+
+ init_sa(&my_sa_data);
+
+ dwOpenMode = PIPE_ACCESS_INBOUND | PIPE_ACCESS_OUTBOUND |
+ FILE_FLAG_OVERLAPPED;
+
+ dwPipeMode = PIPE_TYPE_MESSAGE | PIPE_READMODE_BYTE | PIPE_WAIT |
+ PIPE_REJECT_REMOTE_CLIENTS;
+
+ if (is_first) {
+ dwOpenMode |= FILE_FLAG_FIRST_PIPE_INSTANCE;
+
+ /*
+ * On Windows, the first server pipe instance gets to
+ * set the ACL / Security Attributes on the named
+ * pipe; subsequent instances inherit and cannot
+ * change them.
+ */
+ get_sa(&my_sa_data);
+ }
+
+ hPipe = CreateNamedPipeW(wpath, dwOpenMode, dwPipeMode,
+ PIPE_UNLIMITED_INSTANCES, 1024, 1024, 0,
+ my_sa_data.lpSA);
+
+ release_sa(&my_sa_data);
+
+ return hPipe;
+}
+
+int ipc_server_run_async(struct ipc_server_data **returned_server_data,
+ const char *path, const struct ipc_server_opts *opts,
+ ipc_server_application_cb *application_cb,
+ void *application_data)
+{
+ struct ipc_server_data *server_data;
+ wchar_t wpath[MAX_PATH];
+ HANDLE hPipeFirst = INVALID_HANDLE_VALUE;
+ int k;
+ int ret = 0;
+ int nr_threads = opts->nr_threads;
+
+ *returned_server_data = NULL;
+
+ ret = initialize_pipe_name(path, wpath, ARRAY_SIZE(wpath));
+ if (ret < 0) {
+ errno = EINVAL;
+ return -1;
+ }
+
+ hPipeFirst = create_new_pipe(wpath, 1);
+ if (hPipeFirst == INVALID_HANDLE_VALUE) {
+ errno = EADDRINUSE;
+ return -2;
+ }
+
+ server_data = xcalloc(1, sizeof(*server_data));
+ server_data->magic = MAGIC_SERVER_DATA;
+ server_data->application_cb = application_cb;
+ server_data->application_data = application_data;
+ server_data->hEventStopRequested = CreateEvent(NULL, TRUE, FALSE, NULL);
+ strbuf_init(&server_data->buf_path, 0);
+ strbuf_addstr(&server_data->buf_path, path);
+ wcscpy(server_data->wpath, wpath);
+
+ if (nr_threads < 1)
+ nr_threads = 1;
+
+ for (k = 0; k < nr_threads; k++) {
+ struct ipc_server_thread_data *std;
+
+ std = xcalloc(1, sizeof(*std));
+ std->magic = MAGIC_SERVER_THREAD_DATA;
+ std->server_data = server_data;
+ std->hPipe = INVALID_HANDLE_VALUE;
+
+ std->hPipe = (k == 0)
+ ? hPipeFirst
+ : create_new_pipe(server_data->wpath, 0);
+
+ if (std->hPipe == INVALID_HANDLE_VALUE) {
+ /*
+ * If we've reached a pipe instance limit for
+ * this path, just use fewer threads.
+ */
+ free(std);
+ break;
+ }
+
+ if (pthread_create(&std->pthread_id, NULL,
+ server_thread_proc, std)) {
+ /*
+ * Likewise, if we're out of threads, just use
+ * fewer threads than requested.
+ *
+ * However, we just give up if we can't even get
+ * one thread. This should not happen.
+ */
+ if (k == 0)
+ die(_("could not start thread[0] for '%s'"),
+ path);
+
+ CloseHandle(std->hPipe);
+ free(std);
+ break;
+ }
+
+ std->next_thread = server_data->thread_list;
+ server_data->thread_list = std;
+ }
+
+ *returned_server_data = server_data;
+ return 0;
+}
+
+int ipc_server_stop_async(struct ipc_server_data *server_data)
+{
+ if (!server_data)
+ return 0;
+
+ /*
+ * Gently tell all of the ipc_server threads to shutdown.
+ * This will be seen the next time they are idle (and waiting
+ * for a connection).
+ *
+ * We DO NOT attempt to force them to drop an active connection.
+ */
+ SetEvent(server_data->hEventStopRequested);
+ return 0;
+}
+
+int ipc_server_await(struct ipc_server_data *server_data)
+{
+ DWORD dwWaitResult;
+
+ if (!server_data)
+ return 0;
+
+ dwWaitResult = WaitForSingleObject(server_data->hEventStopRequested, INFINITE);
+ if (dwWaitResult != WAIT_OBJECT_0)
+ return error(_("wait for hEvent failed for '%s'"),
+ server_data->buf_path.buf);
+
+ while (server_data->thread_list) {
+ struct ipc_server_thread_data *std = server_data->thread_list;
+
+ pthread_join(std->pthread_id, NULL);
+
+ server_data->thread_list = std->next_thread;
+ free(std);
+ }
+
+ server_data->is_stopped = 1;
+
+ return 0;
+}
+
+void ipc_server_free(struct ipc_server_data *server_data)
+{
+ if (!server_data)
+ return;
+
+ if (!server_data->is_stopped)
+ BUG("cannot free ipc-server while running for '%s'",
+ server_data->buf_path.buf);
+
+ strbuf_release(&server_data->buf_path);
+
+ if (server_data->hEventStopRequested != INVALID_HANDLE_VALUE)
+ CloseHandle(server_data->hEventStopRequested);
+
+ while (server_data->thread_list) {
+ struct ipc_server_thread_data *std = server_data->thread_list;
+
+ server_data->thread_list = std->next_thread;
+ free(std);
+ }
+
+ free(server_data);
+}