X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fcompat%2Fdirectory-handle.c;h=eb1cd926e6e2df0979d041a21532a7a6b141b050;hp=d9d1e233757bdb76bbabdc51436ac13b02388574;hb=ab5be9fa2eb5ba9600a82cd18fd3cfcbac69169a;hpb=cbf53d23cecaca9c6ec71582663c4a8254a9f285

diff --git a/src/common/compat/directory-handle.c b/src/common/compat/directory-handle.c
index d9d1e2337..eb1cd926e 100644
--- a/src/common/compat/directory-handle.c
+++ b/src/common/compat/directory-handle.c
@@ -1,18 +1,8 @@
 /*
- * Copyright (C) 2019 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ * Copyright (C) 2019 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/compat/directory-handle.h>
@@ -36,9 +26,6 @@
  * of the internal API below.
  */
 static
-int lttng_directory_handle_stat(const struct lttng_directory_handle *handle,
-		const char *path, struct stat *st);
-static
 int lttng_directory_handle_mkdir(
 		const struct lttng_directory_handle *handle,
 		const char *path, mode_t mode);
@@ -93,6 +80,26 @@ void lttng_directory_handle_release(struct urcu_ref *ref);
 
 #ifdef COMPAT_DIRFD
 
+/*
+ * Special inode number reserved to represent the "current working directory".
+ * ino_t is spec'ed as being an unsigned integral type.
+ */
+#define RESERVED_AT_FDCWD_INO                      \
+	({                                         \
+		uint64_t reserved_val;             \
+		switch (sizeof(ino_t)) {           \
+		case 4:                            \
+			reserved_val = UINT32_MAX; \
+			break;                     \
+		case 8:                            \
+			reserved_val = UINT64_MAX; \
+			break;                     \
+		default:                           \
+			abort();                   \
+		}                                  \
+		(ino_t) reserved_val;              \
+	})
+
 LTTNG_HIDDEN
 struct lttng_directory_handle *lttng_directory_handle_create(const char *path)
 {
@@ -144,11 +151,23 @@ LTTNG_HIDDEN
 struct lttng_directory_handle *lttng_directory_handle_create_from_dirfd(
 		int dirfd)
 {
+	int ret;
 	struct lttng_directory_handle *handle = zmalloc(sizeof(*handle));
+	struct stat stat_buf;
 
 	if (!handle) {
 		goto end;
 	}
+
+	if (dirfd != AT_FDCWD) {
+		ret = fstat(dirfd, &stat_buf);
+		if (ret) {
+			PERROR("Failed to fstat directory file descriptor %i", dirfd);
+			lttng_directory_handle_release(&handle->ref);
+		}
+	} else {
+		handle->directory_inode = RESERVED_AT_FDCWD_INO;
+	}
 	handle->dirfd = dirfd;
 	urcu_ref_init(&handle->ref);
 end:
@@ -199,19 +218,33 @@ end:
 	return new_handle;
 }
 
+LTTNG_HIDDEN
+bool lttng_directory_handle_equals(const struct lttng_directory_handle *lhs,
+		const struct lttng_directory_handle *rhs)
+{
+	return lhs->directory_inode == rhs->directory_inode;
+}
+
 static
 void lttng_directory_handle_invalidate(struct lttng_directory_handle *handle)
 {
 	handle->dirfd = -1;
 }
 
-static
+LTTNG_HIDDEN
 int lttng_directory_handle_stat(const struct lttng_directory_handle *handle,
 		const char *path, struct stat *st)
 {
 	return fstatat(handle->dirfd, path, st, 0);
 }
 
+LTTNG_HIDDEN
+bool lttng_directory_handle_uses_fd(
+		const struct lttng_directory_handle *handle)
+{
+	return handle->dirfd != AT_FDCWD;
+}
+
 static
 int lttng_directory_handle_mkdir(
 		const struct lttng_directory_handle *handle,
@@ -550,13 +583,20 @@ end:
 	return new_handle;
 }
 
+LTTNG_HIDDEN
+bool lttng_directory_handle_equals(const struct lttng_directory_handle *lhs,
+		const struct lttng_directory_handle *rhs)
+{
+	return strcmp(lhs->path, rhs->path) == 0;
+}
+
 static
 void lttng_directory_handle_invalidate(struct lttng_directory_handle *handle)
 {
 	handle->base_path = NULL;
 }
 
-static
+LTTNG_HIDDEN
 int lttng_directory_handle_stat(const struct lttng_directory_handle *handle,
 		const char *subdirectory, struct stat *st)
 {
@@ -574,6 +614,13 @@ end:
 	return ret;
 }
 
+LTTNG_HIDDEN
+bool lttng_directory_handle_uses_fd(
+		const struct lttng_directory_handle *handle)
+{
+	return false;
+}
+
 static
 int lttng_directory_handle_mkdir(const struct lttng_directory_handle *handle,
 		const char *subdirectory, mode_t mode)