| 1 | /* |
| 2 | * SPDX-License-Identifier: LGPL-2.1-only |
| 3 | * |
| 4 | * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 5 | */ |
| 6 | |
| 7 | #include <urcu/compiler.h> |
| 8 | #include <urcu/system.h> |
| 9 | |
| 10 | #include "common/logging.h" |
| 11 | |
| 12 | int lttng_ust_log_level = LTTNG_UST_LOG_LEVEL_UNKNOWN; |
| 13 | int lttng_ust_log_critical_action = LTTNG_UST_LOG_CRITICAL_ACTION_UNKNOWN; |
| 14 | |
| 15 | /* |
| 16 | * Initialize the global log level from the "LTTNG_UST_DEBUG" environment |
| 17 | * variable. |
| 18 | * |
| 19 | * This could end up being called concurrently by multiple threads but doesn't |
| 20 | * require a mutex since the input is invariant across threads and the result |
| 21 | * will be the same. |
| 22 | */ |
| 23 | static |
| 24 | void lttng_ust_logging_log_level_init(void) |
| 25 | { |
| 26 | char *lttng_ust_debug; |
| 27 | int current_log_level; |
| 28 | |
| 29 | current_log_level = CMM_LOAD_SHARED(lttng_ust_log_level); |
| 30 | |
| 31 | /* |
| 32 | * Check early if we are initialized, this is unlikely as it's already tested |
| 33 | * in lttng_ust_logging_debug_enabled before performing lazy initialization. |
| 34 | */ |
| 35 | if (caa_unlikely(current_log_level != LTTNG_UST_LOG_LEVEL_UNKNOWN)) |
| 36 | return; |
| 37 | |
| 38 | /* |
| 39 | * This getenv is not part of lttng_ust_getenv() because logging is |
| 40 | * used in the getenv initialization and thus logging must be |
| 41 | * initialized prior to getenv. |
| 42 | */ |
| 43 | lttng_ust_debug = getenv("LTTNG_UST_DEBUG"); |
| 44 | |
| 45 | /* |
| 46 | * If the LTTNG_UST_DEBUG environment variable is defined, print all |
| 47 | * messages, otherwise print nothing. |
| 48 | */ |
| 49 | if (lttng_ust_debug) |
| 50 | current_log_level = LTTNG_UST_LOG_LEVEL_DEBUG; |
| 51 | else |
| 52 | current_log_level = LTTNG_UST_LOG_LEVEL_SILENT; |
| 53 | |
| 54 | /* Initialize the log level */ |
| 55 | CMM_STORE_SHARED(lttng_ust_log_level, current_log_level); |
| 56 | } |
| 57 | |
| 58 | /* |
| 59 | * Initialize the global log critical action from the "LTTNG_UST_ABORT_ON_CRITICAL" |
| 60 | * environment variable. |
| 61 | * |
| 62 | * This could end up being called concurrently by multiple threads but doesn't |
| 63 | * require a mutex since the input is invariant across threads and the result |
| 64 | * will be the same. |
| 65 | */ |
| 66 | static |
| 67 | void lttng_ust_logging_log_critical_action_init(void) |
| 68 | { |
| 69 | char *lttng_ust_abort_on_critical; |
| 70 | int current_log_critical_action; |
| 71 | |
| 72 | current_log_critical_action = CMM_LOAD_SHARED(lttng_ust_log_critical_action); |
| 73 | |
| 74 | /* |
| 75 | * Check early if we are initialized, this is unlikely as it's already tested |
| 76 | * in lttng_ust_logging_abort_on_critical_enabled before performing lazy initialization. |
| 77 | */ |
| 78 | if (caa_unlikely(current_log_critical_action != LTTNG_UST_LOG_CRITICAL_ACTION_UNKNOWN)) |
| 79 | return; |
| 80 | |
| 81 | /* |
| 82 | * This getenv is not part of lttng_ust_getenv() because logging is |
| 83 | * used in the getenv initialization and thus logging must be |
| 84 | * initialized prior to getenv. |
| 85 | */ |
| 86 | lttng_ust_abort_on_critical = getenv("LTTNG_UST_ABORT_ON_CRITICAL"); |
| 87 | |
| 88 | /* |
| 89 | * If the LTTNG_UST_ABORT_ON_CRITICAL environment variable is defined, |
| 90 | * call abort() on CRIT(), otherwise take no action. |
| 91 | */ |
| 92 | if (lttng_ust_abort_on_critical) |
| 93 | current_log_critical_action = LTTNG_UST_LOG_CRITICAL_ACTION_ABORT; |
| 94 | else |
| 95 | current_log_critical_action = LTTNG_UST_LOG_CRITICAL_ACTION_NONE; |
| 96 | |
| 97 | /* Initialize the log critical action */ |
| 98 | CMM_STORE_SHARED(lttng_ust_log_critical_action, current_log_critical_action); |
| 99 | } |
| 100 | |
| 101 | /* |
| 102 | * Initialize the global log level from the "LTTNG_UST_DEBUG" environment |
| 103 | * variable and the global log critical action from "LTTNG_UST_ABORT_ON_CRITICAL". |
| 104 | * |
| 105 | * This could end up being called concurrently by multiple threads but doesn't |
| 106 | * require a mutex since the input is invariant across threads and the result |
| 107 | * will be the same. |
| 108 | */ |
| 109 | void lttng_ust_logging_init(void) |
| 110 | { |
| 111 | lttng_ust_logging_log_level_init(); |
| 112 | lttng_ust_logging_log_critical_action_init(); |
| 113 | } |