X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Ffd-tracker%2Futils.c;h=fe2cdcc4ed4f84f1c629e27c630964d25d10f377;hp=b3df040c2088b22fce9d5cd10b3b05f8dfc02634;hb=dd95933f8371a8c81ffc1dc5b306f2263f1ff808;hpb=5c1f54d1d586f61a92704753411bd82c5c928218

diff --git a/src/common/fd-tracker/utils.c b/src/common/fd-tracker/utils.c
index b3df040c2..fe2cdcc4e 100644
--- a/src/common/fd-tracker/utils.c
+++ b/src/common/fd-tracker/utils.c
@@ -1,43 +1,39 @@
 /*
- * Copyright (C) 2018 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ * Copyright (C) 2018 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License, version 2 only, as
- * published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
  *
- * This program is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along with
- * this program; if not, write to the Free Software Foundation, Inc., 51
- * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#include <common/error.h>
 #include <common/fd-tracker/utils.h>
 #include <common/utils.h>
+#include <lttng/constant.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
 
-static int open_pipe_cloexec(void *data, int *fds)
+static
+int open_pipe_cloexec(void *data, int *fds)
 {
 	return utils_create_pipe_cloexec(fds);
 }
 
-static int close_pipe(void *data, int *pipe)
+static
+int close_pipe(void *data, int *pipe)
 {
 	utils_close_pipe(pipe);
 	pipe[0] = pipe[1] = -1;
 	return 0;
 }
 
+LTTNG_HIDDEN
 int fd_tracker_util_close_fd(void *unused, int *fd)
 {
 	return close(*fd);
 }
 
+LTTNG_HIDDEN
 int fd_tracker_util_pipe_open_cloexec(
 		struct fd_tracker *tracker, const char *name, int *pipe)
 {
@@ -63,8 +59,134 @@ end:
 	return ret;
 }
 
+LTTNG_HIDDEN
 int fd_tracker_util_pipe_close(struct fd_tracker *tracker, int *pipe)
 {
 	return fd_tracker_close_unsuspendable_fd(
 			tracker, pipe, 2, close_pipe, NULL);
 }
+
+struct open_directory_handle_args {
+	const struct lttng_directory_handle *in_handle;
+	struct lttng_directory_handle *ret_handle;
+	const char *path;
+};
+
+static
+int open_directory_handle(void *_args, int *out_fds)
+{
+	int ret = 0;
+	struct open_directory_handle_args *args = _args;
+	struct lttng_directory_handle *new_handle = NULL;
+
+	new_handle = args->in_handle ?
+			lttng_directory_handle_create_from_handle(
+				args->path, args->in_handle) :
+			lttng_directory_handle_create(args->path);
+	if (!new_handle) {
+		ret = -errno;
+		goto end;
+	}
+
+	args->ret_handle = new_handle;
+
+	/*
+	 * Reserved to indicate that the handle does not use a handle; there is
+	 * nothing to track. We want to indicate an error to the fd-tracker so
+	 * that it doesn't attempt to track the file descriptor, but also want
+	 * the caller to retrieve the newly-created handle.
+	 *
+	 * Calling this a hack is a fair assessment.
+	 */
+	if (!lttng_directory_handle_uses_fd(new_handle)) {
+		ret = ENOTSUP;
+	} else {
+#ifdef COMPAT_DIRFD
+		*out_fds = new_handle->dirfd;
+#else
+		abort();
+#endif
+
+	}
+end:
+	return ret;
+}
+
+#ifdef COMPAT_DIRFD
+static
+int fd_close(void *unused, int *in_fds)
+{
+	const int ret = close(in_fds[0]);
+
+	in_fds[0] = -1;
+	return ret;
+}
+
+static
+void directory_handle_destroy(
+		struct lttng_directory_handle *handle, void *data)
+{
+	struct fd_tracker *tracker = data;
+	const int ret = fd_tracker_close_unsuspendable_fd(
+			tracker, &handle->dirfd, 1, fd_close, NULL);
+
+	if (ret) {
+		ERR("Failed to untrack directory handle file descriptor");
+	}
+}
+#endif
+
+LTTNG_HIDDEN
+struct lttng_directory_handle *fd_tracker_create_directory_handle(
+		struct fd_tracker *tracker, const char *path)
+{
+	return fd_tracker_create_directory_handle_from_handle(
+			tracker, NULL, path);
+}
+
+LTTNG_HIDDEN
+struct lttng_directory_handle *fd_tracker_create_directory_handle_from_handle(
+		struct fd_tracker *tracker,
+		struct lttng_directory_handle *in_handle,
+		const char *path)
+{
+	int ret;
+	int dirfd = -1;
+	char *handle_name = NULL;
+	char cwd_path[LTTNG_PATH_MAX] = "working directory";
+	struct lttng_directory_handle *new_handle = NULL;
+	struct open_directory_handle_args open_args = {
+		.in_handle = in_handle,
+		.path = path,
+	};
+
+	if (!path) {
+		if (!getcwd(cwd_path, sizeof(cwd_path))) {
+			PERROR("Failed to get current working directory to name directory handle");
+			goto end;
+		}
+	}
+
+	ret = asprintf(&handle_name, "Directory handle to %s",
+			path ? path : cwd_path);
+	if (ret < 0) {
+		PERROR("Failed to format directory handle name");
+		goto end;
+	}
+
+	ret = fd_tracker_open_unsuspendable_fd(tracker, &dirfd,
+			(const char **) &handle_name, 1, open_directory_handle,
+			&open_args);
+	if (ret && ret != ENOTSUP) {
+		ERR("Failed to open directory handle to %s through the fd tracker", path ? path : cwd_path);
+	}
+	new_handle = open_args.ret_handle;
+
+#ifdef COMPAT_DIRFD
+	new_handle->destroy_cb = directory_handle_destroy;
+	new_handle->destroy_cb_data = tracker;
+#endif
+end:
+	free(handle_name);
+	return new_handle;
+}