| 1 | /* |
| 2 | * Copyright (C) 2022 Jérémie Galarneau <jeremie.galarneau@efficios.com> |
| 3 | * |
| 4 | * SPDX-License-Identifier: GPL-2.0-only |
| 5 | * |
| 6 | */ |
| 7 | |
| 8 | #include "ust-registry.hpp" |
| 9 | |
| 10 | #include <common/compat/directory-handle.hpp> |
| 11 | #include <common/error.hpp> |
| 12 | #include <common/exception.hpp> |
| 13 | #include <common/macros.hpp> |
| 14 | #include <common/pthread-lock.hpp> |
| 15 | #include <common/runas.hpp> |
| 16 | |
| 17 | #include <fcntl.h> |
| 18 | #include <sstream> |
| 19 | #include <string> |
| 20 | |
| 21 | ust_registry_session::ust_registry_session(uint32_t bits_per_long, |
| 22 | uint32_t uint8_t_alignment, |
| 23 | uint32_t uint16_t_alignment, |
| 24 | uint32_t uint32_t_alignment, |
| 25 | uint32_t uint64_t_alignment, |
| 26 | uint32_t long_alignment, |
| 27 | int byte_order, |
| 28 | uint32_t major, |
| 29 | uint32_t minor, |
| 30 | const char *root_shm_path, |
| 31 | const char *shm_path, |
| 32 | uid_t euid, |
| 33 | gid_t egid, |
| 34 | uint64_t tracing_id) : |
| 35 | _bits_per_long{bits_per_long}, |
| 36 | _uint8_t_alignment{uint8_t_alignment}, |
| 37 | _uint16_t_alignment{uint16_t_alignment}, |
| 38 | _uint32_t_alignment{uint32_t_alignment}, |
| 39 | _uint64_t_alignment{uint64_t_alignment}, |
| 40 | _long_alignment{long_alignment}, |
| 41 | _byte_order{byte_order}, |
| 42 | _uid{euid}, |
| 43 | _gid{egid}, |
| 44 | _app_tracer_version_major{major}, |
| 45 | _app_tracer_version_minor{minor}, |
| 46 | _tracing_id{tracing_id} |
| 47 | { |
| 48 | pthread_mutex_init(&_lock, NULL); |
| 49 | strncpy(_root_shm_path, root_shm_path, sizeof(_root_shm_path)); |
| 50 | _root_shm_path[sizeof(_root_shm_path) - 1] = '\0'; |
| 51 | if (shm_path[0]) { |
| 52 | strncpy(_shm_path, shm_path, sizeof(_shm_path)); |
| 53 | _shm_path[sizeof(_shm_path) - 1] = '\0'; |
| 54 | strncpy(_metadata_path, shm_path, sizeof(_metadata_path)); |
| 55 | _metadata_path[sizeof(_metadata_path) - 1] = '\0'; |
| 56 | strncat(_metadata_path, "/metadata", |
| 57 | sizeof(_metadata_path) - strlen(_metadata_path) - 1); |
| 58 | } |
| 59 | |
| 60 | if (_shm_path[0]) { |
| 61 | if (run_as_mkdir_recursive(_shm_path, S_IRWXU | S_IRWXG, euid, egid)) { |
| 62 | LTTNG_THROW_POSIX("run_as_mkdir_recursive", errno); |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | if (_metadata_path[0]) { |
| 67 | /* Create metadata file. */ |
| 68 | const int ret = run_as_open(_metadata_path, O_WRONLY | O_CREAT | O_EXCL, |
| 69 | S_IRUSR | S_IWUSR, euid, egid); |
| 70 | |
| 71 | if (ret < 0) { |
| 72 | std::stringstream ss; |
| 73 | |
| 74 | ss << "Opening metadata file '" << _metadata_path << "'"; |
| 75 | LTTNG_THROW_POSIX(ss.str(), errno); |
| 76 | } |
| 77 | |
| 78 | _metadata_fd = ret; |
| 79 | } |
| 80 | |
| 81 | _enums.reset(lttng_ht_new(0, LTTNG_HT_TYPE_STRING)); |
| 82 | if (!_enums) { |
| 83 | LTTNG_THROW_POSIX("Failed to create enums hash table", ENOMEM); |
| 84 | } |
| 85 | |
| 86 | /* hash/match functions are specified at call site. */ |
| 87 | _enums->match_fct = NULL; |
| 88 | _enums->hash_fct = NULL; |
| 89 | |
| 90 | _channels.reset(lttng_ht_new(0, LTTNG_HT_TYPE_U64)); |
| 91 | if (!_channels) { |
| 92 | LTTNG_THROW_POSIX("Failed to create channels hash table", ENOMEM); |
| 93 | } |
| 94 | |
| 95 | if (lttng_uuid_generate(_uuid)) { |
| 96 | LTTNG_THROW_POSIX("Failed to generate UST uuid", errno); |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | ust_registry_session::~ust_registry_session() |
| 101 | { |
| 102 | int ret; |
| 103 | struct lttng_ht_iter iter; |
| 104 | struct ust_registry_channel *chan; |
| 105 | struct ust_registry_enum *reg_enum; |
| 106 | |
| 107 | /* On error, EBUSY can be returned if lock. Code flow error. */ |
| 108 | ret = pthread_mutex_destroy(&_lock); |
| 109 | LTTNG_ASSERT(!ret); |
| 110 | |
| 111 | if (_channels) { |
| 112 | rcu_read_lock(); |
| 113 | /* Destroy all event associated with this registry. */ |
| 114 | cds_lfht_for_each_entry (_channels->ht, &iter.iter, chan, node.node) { |
| 115 | /* Delete the node from the ht and free it. */ |
| 116 | ret = lttng_ht_del(_channels.get(), &iter); |
| 117 | LTTNG_ASSERT(!ret); |
| 118 | ust_registry_channel_destroy(chan, true); |
| 119 | } |
| 120 | |
| 121 | rcu_read_unlock(); |
| 122 | } |
| 123 | |
| 124 | free(_metadata); |
| 125 | if (_metadata_fd >= 0) { |
| 126 | ret = close(_metadata_fd); |
| 127 | if (ret) { |
| 128 | PERROR("close"); |
| 129 | } |
| 130 | |
| 131 | ret = run_as_unlink(_metadata_path, _uid, _gid); |
| 132 | if (ret) { |
| 133 | PERROR("unlink"); |
| 134 | } |
| 135 | } |
| 136 | |
| 137 | if (_root_shm_path[0]) { |
| 138 | /* Try to delete the directory hierarchy. */ |
| 139 | (void) run_as_rmdir_recursive(_root_shm_path, _uid, _gid, |
| 140 | LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG); |
| 141 | } |
| 142 | |
| 143 | /* Destroy the enum hash table */ |
| 144 | if (_enums) { |
| 145 | rcu_read_lock(); |
| 146 | /* Destroy all enum entries associated with this registry. */ |
| 147 | cds_lfht_for_each_entry (_enums->ht, &iter.iter, reg_enum, node.node) { |
| 148 | ust_registry_destroy_enum(this, reg_enum); |
| 149 | } |
| 150 | |
| 151 | rcu_read_unlock(); |
| 152 | } |
| 153 | } |
| 154 | |
| 155 | void ust_registry_session::statedump() |
| 156 | { |
| 157 | lttng::pthread::lock_guard registry_lock(_lock); |
| 158 | |
| 159 | const int ret = ust_metadata_session_statedump(this); |
| 160 | if (ret) { |
| 161 | LTTNG_THROW_ERROR( |
| 162 | "Failed to generate session metadata during registry session creation"); |
| 163 | } |
| 164 | } |