| 1 | /* |
| 2 | * SPDX-License-Identifier: LGPL-2.1-only |
| 3 | * |
| 4 | * Copyright (C) 2016 EfficiOS Inc. |
| 5 | * Copyright (C) 2016 Alexandre Montplaisir <alexmonthy@efficios.com> |
| 6 | * Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 7 | */ |
| 8 | |
| 9 | #include "org_lttng_ust_agent_context_LttngContextApi.h" |
| 10 | |
| 11 | #include <string.h> |
| 12 | #include <inttypes.h> |
| 13 | #include <lttng/ust-events.h> |
| 14 | #include <lttng/ust-ringbuffer-context.h> |
| 15 | #include <common/ust-context-provider.h> |
| 16 | |
| 17 | #include "common/macros.h" |
| 18 | #include "lttng_ust_context.h" |
| 19 | |
| 20 | enum lttng_ust_jni_type { |
| 21 | JNI_TYPE_NULL = 0, |
| 22 | JNI_TYPE_INTEGER = 1, |
| 23 | JNI_TYPE_LONG = 2, |
| 24 | JNI_TYPE_DOUBLE = 3, |
| 25 | JNI_TYPE_FLOAT = 4, |
| 26 | JNI_TYPE_BYTE = 5, |
| 27 | JNI_TYPE_SHORT = 6, |
| 28 | JNI_TYPE_BOOLEAN = 7, |
| 29 | JNI_TYPE_STRING = 8, |
| 30 | }; |
| 31 | |
| 32 | struct lttng_ust_jni_ctx_entry { |
| 33 | int32_t context_name_offset; |
| 34 | char type; /* enum lttng_ust_jni_type */ |
| 35 | union { |
| 36 | int32_t _integer; |
| 37 | int64_t _long; |
| 38 | double _double; |
| 39 | float _float; |
| 40 | signed char _byte; |
| 41 | int16_t _short; |
| 42 | signed char _boolean; |
| 43 | int32_t _string_offset; |
| 44 | } value; |
| 45 | } __attribute__((packed)); |
| 46 | |
| 47 | struct lttng_ust_jni_provider { |
| 48 | struct lttng_ust_registered_context_provider *reg_provider; |
| 49 | char *name; |
| 50 | struct lttng_ust_context_provider provider; |
| 51 | }; |
| 52 | |
| 53 | /* TLS passing context info from JNI to callbacks. */ |
| 54 | __thread struct lttng_ust_jni_tls lttng_ust_context_info_tls; |
| 55 | |
| 56 | static const char *get_ctx_string_at_offset(int32_t offset) |
| 57 | { |
| 58 | signed char *ctx_strings_array = lttng_ust_context_info_tls.ctx_strings; |
| 59 | |
| 60 | if (offset < 0 || offset >= lttng_ust_context_info_tls.ctx_strings_len) { |
| 61 | return NULL; |
| 62 | } |
| 63 | return (const char *) (ctx_strings_array + offset); |
| 64 | } |
| 65 | |
| 66 | static struct lttng_ust_jni_ctx_entry *lookup_ctx_by_name(const char *ctx_name) |
| 67 | { |
| 68 | struct lttng_ust_jni_ctx_entry *ctx_entries_array = lttng_ust_context_info_tls.ctx_entries; |
| 69 | int i, len = lttng_ust_context_info_tls.ctx_entries_len / sizeof(struct lttng_ust_jni_ctx_entry); |
| 70 | |
| 71 | for (i = 0; i < len; i++) { |
| 72 | int32_t offset = ctx_entries_array[i].context_name_offset; |
| 73 | const char *string = get_ctx_string_at_offset(offset); |
| 74 | |
| 75 | if (string && strcmp(string, ctx_name) == 0) { |
| 76 | return &ctx_entries_array[i]; |
| 77 | } |
| 78 | } |
| 79 | return NULL; |
| 80 | } |
| 81 | |
| 82 | static size_t get_size_cb(void *priv, struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)), |
| 83 | size_t offset) |
| 84 | { |
| 85 | const struct lttng_ust_app_context *app_ctx = (const struct lttng_ust_app_context *) priv; |
| 86 | const char *ctx_name = app_ctx->ctx_name; |
| 87 | struct lttng_ust_jni_ctx_entry *jctx; |
| 88 | size_t size = 0; |
| 89 | enum lttng_ust_jni_type jni_type; |
| 90 | |
| 91 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(char)); |
| 92 | size += sizeof(char); /* tag */ |
| 93 | jctx = lookup_ctx_by_name(ctx_name); |
| 94 | if (!jctx) { |
| 95 | jni_type = JNI_TYPE_NULL; |
| 96 | } else { |
| 97 | jni_type = jctx->type; |
| 98 | } |
| 99 | switch (jni_type) { |
| 100 | case JNI_TYPE_NULL: |
| 101 | break; |
| 102 | case JNI_TYPE_INTEGER: |
| 103 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(int32_t)); |
| 104 | size += sizeof(int32_t); /* variant */ |
| 105 | break; |
| 106 | case JNI_TYPE_LONG: |
| 107 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(int64_t)); |
| 108 | size += sizeof(int64_t); /* variant */ |
| 109 | break; |
| 110 | case JNI_TYPE_DOUBLE: |
| 111 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(double)); |
| 112 | size += sizeof(double); /* variant */ |
| 113 | break; |
| 114 | case JNI_TYPE_FLOAT: |
| 115 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(float)); |
| 116 | size += sizeof(float); /* variant */ |
| 117 | break; |
| 118 | case JNI_TYPE_SHORT: |
| 119 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(int16_t)); |
| 120 | size += sizeof(int16_t); /* variant */ |
| 121 | break; |
| 122 | case JNI_TYPE_BYTE: /* Fall-through. */ |
| 123 | case JNI_TYPE_BOOLEAN: |
| 124 | size += lttng_ust_ring_buffer_align(offset, lttng_ust_rb_alignof(char)); |
| 125 | size += sizeof(char); /* variant */ |
| 126 | break; |
| 127 | case JNI_TYPE_STRING: |
| 128 | { |
| 129 | /* The value is an offset, the string is in the "strings" array */ |
| 130 | int32_t string_offset = jctx->value._string_offset; |
| 131 | const char *string = get_ctx_string_at_offset(string_offset); |
| 132 | |
| 133 | if (string) { |
| 134 | size += strlen(string) + 1; |
| 135 | } |
| 136 | break; |
| 137 | } |
| 138 | default: |
| 139 | abort(); |
| 140 | } |
| 141 | return size; |
| 142 | |
| 143 | } |
| 144 | |
| 145 | static void record_cb(void *priv, |
| 146 | struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)), |
| 147 | struct lttng_ust_ring_buffer_ctx *ctx, |
| 148 | struct lttng_ust_channel_buffer *lttng_chan_buf) |
| 149 | { |
| 150 | const struct lttng_ust_app_context *app_ctx = (const struct lttng_ust_app_context *) priv; |
| 151 | const char *ctx_name = app_ctx->ctx_name; |
| 152 | struct lttng_ust_jni_ctx_entry *jctx; |
| 153 | enum lttng_ust_jni_type jni_type; |
| 154 | char sel_char; |
| 155 | |
| 156 | jctx = lookup_ctx_by_name(ctx_name); |
| 157 | if (!jctx) { |
| 158 | jni_type = JNI_TYPE_NULL; |
| 159 | } else { |
| 160 | jni_type = jctx->type; |
| 161 | } |
| 162 | |
| 163 | switch (jni_type) { |
| 164 | case JNI_TYPE_NULL: |
| 165 | sel_char = LTTNG_UST_DYNAMIC_TYPE_NONE; |
| 166 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 167 | break; |
| 168 | case JNI_TYPE_INTEGER: |
| 169 | { |
| 170 | int32_t v = jctx->value._integer; |
| 171 | |
| 172 | sel_char = LTTNG_UST_DYNAMIC_TYPE_S32; |
| 173 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 174 | lttng_chan_buf->ops->event_write(ctx, &v, sizeof(v), lttng_ust_rb_alignof(v)); |
| 175 | break; |
| 176 | } |
| 177 | case JNI_TYPE_LONG: |
| 178 | { |
| 179 | int64_t v = jctx->value._long; |
| 180 | |
| 181 | sel_char = LTTNG_UST_DYNAMIC_TYPE_S64; |
| 182 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 183 | lttng_chan_buf->ops->event_write(ctx, &v, sizeof(v), lttng_ust_rb_alignof(v)); |
| 184 | break; |
| 185 | } |
| 186 | case JNI_TYPE_DOUBLE: |
| 187 | { |
| 188 | double v = jctx->value._double; |
| 189 | |
| 190 | sel_char = LTTNG_UST_DYNAMIC_TYPE_DOUBLE; |
| 191 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 192 | lttng_chan_buf->ops->event_write(ctx, &v, sizeof(v), lttng_ust_rb_alignof(v)); |
| 193 | break; |
| 194 | } |
| 195 | case JNI_TYPE_FLOAT: |
| 196 | { |
| 197 | float v = jctx->value._float; |
| 198 | |
| 199 | sel_char = LTTNG_UST_DYNAMIC_TYPE_FLOAT; |
| 200 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 201 | lttng_chan_buf->ops->event_write(ctx, &v, sizeof(v), lttng_ust_rb_alignof(v)); |
| 202 | break; |
| 203 | } |
| 204 | case JNI_TYPE_SHORT: |
| 205 | { |
| 206 | int16_t v = jctx->value._short; |
| 207 | |
| 208 | sel_char = LTTNG_UST_DYNAMIC_TYPE_S16; |
| 209 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 210 | lttng_chan_buf->ops->event_write(ctx, &v, sizeof(v), lttng_ust_rb_alignof(v)); |
| 211 | break; |
| 212 | } |
| 213 | case JNI_TYPE_BYTE: |
| 214 | { |
| 215 | char v = jctx->value._byte; |
| 216 | |
| 217 | sel_char = LTTNG_UST_DYNAMIC_TYPE_S8; |
| 218 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 219 | lttng_chan_buf->ops->event_write(ctx, &v, sizeof(v), lttng_ust_rb_alignof(v)); |
| 220 | break; |
| 221 | } |
| 222 | case JNI_TYPE_BOOLEAN: |
| 223 | { |
| 224 | char v = jctx->value._boolean; |
| 225 | |
| 226 | sel_char = LTTNG_UST_DYNAMIC_TYPE_S8; |
| 227 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 228 | lttng_chan_buf->ops->event_write(ctx, &v, sizeof(v), lttng_ust_rb_alignof(v)); |
| 229 | break; |
| 230 | } |
| 231 | case JNI_TYPE_STRING: |
| 232 | { |
| 233 | int32_t offset = jctx->value._string_offset; |
| 234 | const char *str = get_ctx_string_at_offset(offset); |
| 235 | |
| 236 | if (str) { |
| 237 | sel_char = LTTNG_UST_DYNAMIC_TYPE_STRING; |
| 238 | } else { |
| 239 | sel_char = LTTNG_UST_DYNAMIC_TYPE_NONE; |
| 240 | } |
| 241 | lttng_chan_buf->ops->event_write(ctx, &sel_char, sizeof(sel_char), lttng_ust_rb_alignof(char)); |
| 242 | if (str) { |
| 243 | lttng_chan_buf->ops->event_write(ctx, str, strlen(str) + 1, 1); |
| 244 | } |
| 245 | break; |
| 246 | } |
| 247 | default: |
| 248 | abort(); |
| 249 | } |
| 250 | } |
| 251 | |
| 252 | static void get_value_cb(void *priv, struct lttng_ust_probe_ctx *probe_ctx __attribute__((unused)), |
| 253 | struct lttng_ust_ctx_value *value) |
| 254 | { |
| 255 | const struct lttng_ust_app_context *app_ctx = (const struct lttng_ust_app_context *) priv; |
| 256 | const char *ctx_name = app_ctx->ctx_name; |
| 257 | struct lttng_ust_jni_ctx_entry *jctx; |
| 258 | enum lttng_ust_jni_type jni_type; |
| 259 | |
| 260 | jctx = lookup_ctx_by_name(ctx_name); |
| 261 | if (!jctx) { |
| 262 | jni_type = JNI_TYPE_NULL; |
| 263 | } else { |
| 264 | jni_type = jctx->type; |
| 265 | } |
| 266 | |
| 267 | switch (jni_type) { |
| 268 | case JNI_TYPE_NULL: |
| 269 | value->sel = LTTNG_UST_DYNAMIC_TYPE_NONE; |
| 270 | break; |
| 271 | case JNI_TYPE_INTEGER: |
| 272 | value->sel = LTTNG_UST_DYNAMIC_TYPE_S64; |
| 273 | value->u.s64 = (int64_t) jctx->value._integer; |
| 274 | break; |
| 275 | case JNI_TYPE_LONG: |
| 276 | value->sel = LTTNG_UST_DYNAMIC_TYPE_S64; |
| 277 | value->u.s64 = jctx->value._long; |
| 278 | break; |
| 279 | case JNI_TYPE_DOUBLE: |
| 280 | value->sel = LTTNG_UST_DYNAMIC_TYPE_DOUBLE; |
| 281 | value->u.d = jctx->value._double; |
| 282 | break; |
| 283 | case JNI_TYPE_FLOAT: |
| 284 | value->sel = LTTNG_UST_DYNAMIC_TYPE_DOUBLE; |
| 285 | value->u.d = (double) jctx->value._float; |
| 286 | break; |
| 287 | case JNI_TYPE_SHORT: |
| 288 | value->sel = LTTNG_UST_DYNAMIC_TYPE_S64; |
| 289 | value->u.s64 = (int64_t) jctx->value._short; |
| 290 | break; |
| 291 | case JNI_TYPE_BYTE: |
| 292 | value->sel = LTTNG_UST_DYNAMIC_TYPE_S64; |
| 293 | value->u.s64 = (int64_t) jctx->value._byte; |
| 294 | break; |
| 295 | case JNI_TYPE_BOOLEAN: |
| 296 | value->sel = LTTNG_UST_DYNAMIC_TYPE_S64; |
| 297 | value->u.s64 = (int64_t) jctx->value._boolean; |
| 298 | break; |
| 299 | case JNI_TYPE_STRING: |
| 300 | { |
| 301 | int32_t offset = jctx->value._string_offset; |
| 302 | const char *str = get_ctx_string_at_offset(offset); |
| 303 | |
| 304 | if (str) { |
| 305 | value->sel = LTTNG_UST_DYNAMIC_TYPE_STRING; |
| 306 | value->u.str = str; |
| 307 | } else { |
| 308 | value->sel = LTTNG_UST_DYNAMIC_TYPE_NONE; |
| 309 | } |
| 310 | break; |
| 311 | } |
| 312 | default: |
| 313 | abort(); |
| 314 | } |
| 315 | } |
| 316 | |
| 317 | /* |
| 318 | * Register a context provider to UST. |
| 319 | * |
| 320 | * Called from the Java side when an application registers a context retriever, |
| 321 | * so we create and register a corresponding provider on the C side. |
| 322 | */ |
| 323 | JNIEXPORT jlong JNICALL Java_org_lttng_ust_agent_context_LttngContextApi_registerProvider(JNIEnv *env, |
| 324 | jobject jobj __attribute__((unused)), |
| 325 | jstring provider_name) |
| 326 | { |
| 327 | jboolean iscopy; |
| 328 | const char *provider_name_jstr; |
| 329 | char *provider_name_cstr; |
| 330 | struct lttng_ust_context_provider *provider; |
| 331 | struct lttng_ust_jni_provider *jni_provider; |
| 332 | /* |
| 333 | * Note: a "jlong" is 8 bytes on all architectures, whereas a |
| 334 | * C "long" varies. |
| 335 | */ |
| 336 | jlong provider_ref; |
| 337 | |
| 338 | provider_name_jstr = (*env)->GetStringUTFChars(env, provider_name, &iscopy); |
| 339 | if (!provider_name_jstr) { |
| 340 | goto error_jstr; |
| 341 | } |
| 342 | /* Keep our own copy of the string so UST can use it. */ |
| 343 | provider_name_cstr = strdup(provider_name_jstr); |
| 344 | (*env)->ReleaseStringUTFChars(env, provider_name, provider_name_jstr); |
| 345 | if (!provider_name_cstr) { |
| 346 | goto error_strdup; |
| 347 | } |
| 348 | jni_provider = zmalloc(sizeof(*jni_provider)); |
| 349 | if (!jni_provider) { |
| 350 | goto error_provider; |
| 351 | } |
| 352 | provider = &jni_provider->provider; |
| 353 | provider->struct_size = sizeof(*provider); |
| 354 | jni_provider->name = provider_name_cstr; |
| 355 | provider->name = jni_provider->name; |
| 356 | provider->get_size = get_size_cb; |
| 357 | provider->record = record_cb; |
| 358 | provider->get_value = get_value_cb; |
| 359 | provider->priv = jni_provider; |
| 360 | |
| 361 | jni_provider->reg_provider = lttng_ust_context_provider_register(provider); |
| 362 | if (!jni_provider->reg_provider) { |
| 363 | goto error_register; |
| 364 | } |
| 365 | |
| 366 | provider_ref = (jlong) (long) jni_provider; |
| 367 | return provider_ref; |
| 368 | |
| 369 | /* Error handling. */ |
| 370 | error_register: |
| 371 | free(jni_provider); |
| 372 | error_provider: |
| 373 | free(provider_name_cstr); |
| 374 | error_strdup: |
| 375 | error_jstr: |
| 376 | return 0; |
| 377 | } |
| 378 | |
| 379 | /* |
| 380 | * Unregister a previously-registered context provider. |
| 381 | * |
| 382 | * Called from the Java side when an application unregisters a context retriever, |
| 383 | * so we unregister and delete the corresponding provider on the C side. |
| 384 | */ |
| 385 | JNIEXPORT void JNICALL Java_org_lttng_ust_agent_context_LttngContextApi_unregisterProvider(JNIEnv *env __attribute__((unused)), |
| 386 | jobject jobj __attribute__((unused)), |
| 387 | jlong provider_ref) |
| 388 | { |
| 389 | struct lttng_ust_jni_provider *jni_provider = |
| 390 | (struct lttng_ust_jni_provider *) (unsigned long) provider_ref; |
| 391 | |
| 392 | if (!jni_provider) { |
| 393 | return; |
| 394 | } |
| 395 | |
| 396 | lttng_ust_context_provider_unregister(jni_provider->reg_provider); |
| 397 | |
| 398 | free(jni_provider->name); |
| 399 | free(jni_provider); |
| 400 | } |