X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fcompat%2Fdirectory-handle.h;h=9a107201987f129ee4bd7dbdd12a359893fffebd;hp=ceebc941e724ea690003698eb7c469789f3f2dba;hb=7966af5763c4aaca39df9bbfa9277ff15715c720;hpb=578e21bdc951a54e34fe539b64e446557b703206 diff --git a/src/common/compat/directory-handle.h b/src/common/compat/directory-handle.h index ceebc941e..9a1072019 100644 --- a/src/common/compat/directory-handle.h +++ b/src/common/compat/directory-handle.h @@ -1,25 +1,26 @@ /* - * Copyright (C) 2019 - Jérémie Galarneau + * Copyright (C) 2019 Jérémie Galarneau * - * 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. */ #ifndef _COMPAT_DIRECTORY_HANDLE_H #define _COMPAT_DIRECTORY_HANDLE_H -#include #include +#include +#include +#include + +#ifdef __cplusplus +extern "C" { +#endif + +enum lttng_directory_handle_rmdir_recursive_flags { + LTTNG_DIRECTORY_HANDLE_FAIL_NON_EMPTY_FLAG = (1U << 0), + LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG = (1U << 1), +}; /* * Some platforms, such as Solaris 10, do not support directory file descriptors @@ -28,50 +29,97 @@ * This wrapper provides a handle that is either a copy of a directory's path * or a directory file descriptors, depending on the platform's capabilities. */ -#ifdef COMPAT_DIRFD +#ifdef HAVE_DIRFD + +struct lttng_directory_handle; + +typedef void (*lttng_directory_handle_destroy_cb)( + struct lttng_directory_handle *handle, void *data); + struct lttng_directory_handle { + struct urcu_ref ref; + ino_t directory_inode; int dirfd; + lttng_directory_handle_destroy_cb destroy_cb; + void *destroy_cb_data; }; + +static inline +int lttng_directory_handle_get_dirfd( + const struct lttng_directory_handle *handle) +{ + return handle->dirfd; +} + #else struct lttng_directory_handle { + struct urcu_ref ref; char *base_path; }; #endif /* - * Initialize a directory handle to the provided path. Passing a NULL path - * returns a handle to the current working directory. The working directory - * is not sampled; it will be accessed at the time of use of the functions - * of this API. + * Create a directory handle to the provided path. Passing a NULL path + * returns a handle to the current working directory. * - * An initialized directory handle must be finalized using - * lttng_directory_handle_fini(). + * The reference to the directory handle must be released using + * lttng_directory_handle_put(). */ -LTTNG_HIDDEN -int lttng_directory_handle_init(struct lttng_directory_handle *handle, +struct lttng_directory_handle *lttng_directory_handle_create( const char *path); -LTTNG_HIDDEN -int lttng_directory_handle_init_from_dirfd( - struct lttng_directory_handle *handle, int dirfd); +/* + * Create a new directory handle to a path relative to an existing handle. + * + * The provided path must already exist. Note that the creation of a + * subdirectory and the creation of a handle are kept as separate operations + * to highlight the fact that there is an inherent race between the creation of + * a directory and the creation of a handle to it. + * + * Passing a NULL path effectively copies the original handle. + * + * The reference to the directory handle must be released using + * lttng_directory_handle_put(). + */ +struct lttng_directory_handle *lttng_directory_handle_create_from_handle( + const char *path, + const struct lttng_directory_handle *ref_handle); + +/* + * Create a new directory handle from an existing directory fd. + * + * The new directory handle assumes the ownership of the directory fd. + * Note that this method should only be used in very specific cases, such as + * re-creating a directory handle from a dirfd passed over a unix socket. + * + * The reference to the directory handle must be released using + * lttng_directory_handle_put(). + */ +struct lttng_directory_handle *lttng_directory_handle_create_from_dirfd( + int dirfd); /* * Copy a directory handle. + * + * The reference to the directory handle must be released using + * lttng_directory_handle_put(). + */ +struct lttng_directory_handle *lttng_directory_handle_copy( + const struct lttng_directory_handle *handle); + +/* + * Acquire a reference to a directory handle. */ -LTTNG_HIDDEN -int lttng_directory_handle_copy(const struct lttng_directory_handle *handle, - struct lttng_directory_handle *new_copy); +bool lttng_directory_handle_get(struct lttng_directory_handle *handle); /* - * Release the resources of a directory handle. + * Release a reference to a directory handle. */ -LTTNG_HIDDEN -void lttng_directory_handle_fini(struct lttng_directory_handle *handle); +void lttng_directory_handle_put(struct lttng_directory_handle *handle); /* * Create a subdirectory relative to a directory handle. */ -LTTNG_HIDDEN int lttng_directory_handle_create_subdirectory( const struct lttng_directory_handle *handle, const char *subdirectory, @@ -81,7 +129,6 @@ int lttng_directory_handle_create_subdirectory( * Create a subdirectory relative to a directory handle * as a given user. */ -LTTNG_HIDDEN int lttng_directory_handle_create_subdirectory_as_user( const struct lttng_directory_handle *handle, const char *subdirectory, @@ -90,7 +137,6 @@ int lttng_directory_handle_create_subdirectory_as_user( /* * Recursively create a directory relative to a directory handle. */ -LTTNG_HIDDEN int lttng_directory_handle_create_subdirectory_recursive( const struct lttng_directory_handle *handle, const char *subdirectory_path, @@ -100,10 +146,126 @@ int lttng_directory_handle_create_subdirectory_recursive( * Recursively create a directory relative to a directory handle * as a given user. */ -LTTNG_HIDDEN int lttng_directory_handle_create_subdirectory_recursive_as_user( const struct lttng_directory_handle *handle, const char *subdirectory_path, mode_t mode, const struct lttng_credentials *creds); +/* + * Open a file descriptor to a path relative to a directory handle. + */ +int lttng_directory_handle_open_file( + const struct lttng_directory_handle *handle, + const char *filename, + int flags, mode_t mode); + +/* + * Open a file descriptor to a path relative to a directory handle + * as a given user. + */ +int lttng_directory_handle_open_file_as_user( + const struct lttng_directory_handle *handle, + const char *filename, + int flags, mode_t mode, + const struct lttng_credentials *creds); + +/* + * Unlink a file to a path relative to a directory handle. + */ +int lttng_directory_handle_unlink_file( + const struct lttng_directory_handle *handle, + const char *filename); + +/* + * Unlink a file to a path relative to a directory handle as a given user. + */ +int lttng_directory_handle_unlink_file_as_user( + const struct lttng_directory_handle *handle, + const char *filename, + const struct lttng_credentials *creds); + +/* + * Rename a file from a path relative to a directory handle to a new + * name relative to another directory handle. + */ +int lttng_directory_handle_rename( + const struct lttng_directory_handle *old_handle, + const char *old_name, + const struct lttng_directory_handle *new_handle, + const char *new_name); + +/* + * Rename a file from a path relative to a directory handle to a new + * name relative to another directory handle as a given user. + */ +int lttng_directory_handle_rename_as_user( + const struct lttng_directory_handle *old_handle, + const char *old_name, + const struct lttng_directory_handle *new_handle, + const char *new_name, + const struct lttng_credentials *creds); + +/* + * Remove a subdirectory relative to a directory handle. + */ +int lttng_directory_handle_remove_subdirectory( + const struct lttng_directory_handle *handle, + const char *name); + +/* + * Remove a subdirectory relative to a directory handle as a given user. + */ +int lttng_directory_handle_remove_subdirectory_as_user( + const struct lttng_directory_handle *handle, + const char *name, + const struct lttng_credentials *creds); + +/* + * Remove a subdirectory and remove its contents if it only + * consists in empty directories. + * @flags: enum lttng_directory_handle_rmdir_recursive_flags + */ +int lttng_directory_handle_remove_subdirectory_recursive( + const struct lttng_directory_handle *handle, + const char *name, int flags); + +/* + * Remove a subdirectory and remove its contents if it only + * consists in empty directories as a given user. + * @flags: enum lttng_directory_handle_rmdir_recursive_flags + */ +int lttng_directory_handle_remove_subdirectory_recursive_as_user( + const struct lttng_directory_handle *handle, + const char *name, + const struct lttng_credentials *creds, + int flags); + +/* + * stat() a file relative to a directory handle. + */ +int lttng_directory_handle_stat( + const struct lttng_directory_handle *handle, + const char *name, + struct stat *stat_buf); + +/* + * Returns true if this directory handle is backed by a file + * descriptor, false otherwise. + */ +bool lttng_directory_handle_uses_fd( + const struct lttng_directory_handle *handle); + +/* + * Compare two directory handles. + * + * Returns true if the two directory handles are equal, false otherwise. + */ +bool lttng_directory_handle_equals(const struct lttng_directory_handle *lhs, + const struct lttng_directory_handle *rhs); + + +#ifdef __cplusplus +} +#endif + #endif /* _COMPAT_PATH_HANDLE_H */