1# trace.h 2 3 4## Overview 5 6Defines APIs of the HiTraceMeter module for performance trace. 7 8Example 9 10Synchronous time slice trace event: 11 12 13``` 14OH_HiTrace_StartTrace("hitraceTest"); 15OH_HiTrace_FinishTrace(); 16``` 17 18Output: 19 20 21``` 22<...>-1668 (----—) [003] .... 135.059377: tracing_mark_write: B|1668|H:hitraceTest 23<...>-1668 (----—) [003] .... 135.059415: tracing_mark_write: E|1668| 24``` 25 26Asynchronous time slice trace event: 27 28 29``` 30OH_HiTrace_StartAsyncTrace("hitraceTest", 123); 31OH_HiTrace_FinishAsyncTrace("hitraceTest", 123); 32``` 33 34Output: 35 36 37``` 38<...>-2477 (----—) [001] .... 396.427165: tracing_mark_write: S|2477|H:hitraceTest 123 39<...>-2477 (----—) [001] .... 396.427196: tracing_mark_write: F|2477|H:hitraceTest 123 40``` 41 42Integer value trace event: 43 44 45``` 46OH_HiTrace_CountTrace("hitraceTest", 500); 47``` 48 49Output: 50 51 52``` 53<...>-2638 (----—) [002] .... 458.904382: tracing_mark_write: C|2638|H:hitraceTest 500 54``` 55 56 57**File to include**: 58 59<hitrace/trace.h> 60 61**Since** 62 6310 64 65**Related Modules** 66 67[Hitrace](_hitrace.md) 68 69 70## Summary 71 72 73### Structs 74 75| Name| Description| 76| -------- | -------- | 77| struct [HiTraceId](_hi_trace_id.md) | Defines the **HiTraceId** instance. | 78 79 80### Types 81 82| Name| Description| 83| -------- | -------- | 84| typedef enum [HiTraceId_Valid](_hitrace.md#hitraceid_valid) [HiTraceId_Valid](_hitrace.md#hitraceid_valid) | Defines an enum for whether a **HiTraceId** instance is valid. | 85| typedef enum [HiTrace_Version](_hitrace.md#hitrace_version) [HiTrace_Version](_hitrace.md#hitrace_version) | Defines an enum for the HiTrace versions. | 86| typedef enum [HiTrace_Flag](_hitrace.md#hitrace_flag) [HiTrace_Flag](_hitrace.md#hitrace_flag) | Defines an enum for the HiTrace flags. | 87| typedef enum [HiTrace_Tracepoint_Type](_hitrace.md#hitrace_tracepoint_type) [HiTrace_Tracepoint_Type](_hitrace.md#hitrace_tracepoint_type) | Defines an enum for the HiTrace tracepoint types. | 88| typedef enum [HiTrace_Communication_Mode](_hitrace.md#hitrace_communication_mode) [HiTrace_Communication_Mode](_hitrace.md#hitrace_communication_mode) | Defines an enum for the HiTrace communication modes. | 89| typedef struct [HiTraceId](_hi_trace_id.md)**HiTraceId** | | 90 91 92### Enums 93 94| Name| Description| 95| -------- | -------- | 96| [HiTraceId_Valid](_hitrace.md#hitraceid_valid) { [HITRACE_ID_INVALID](_hitrace.md) = 0, [HITRACE_ID_VALID](_hitrace.md) = 1 } | Enumerates whether a **HiTraceId** instance is valid. | 97| [HiTrace_Version](_hitrace.md#hitrace_version) { [HITRACE_VER_1](_hitrace.md) = 0 } | Enumerates the HiTrace versions. | 98| [HiTrace_Flag](_hitrace.md#hitrace_flag) {<br>[HITRACE_FLAG_DEFAULT](_hitrace.md) = 0, [HITRACE_FLAG_INCLUDE_ASYNC](_hitrace.md) = 1 << 0, [HITRACE_FLAG_DONOT_CREATE_SPAN](_hitrace.md) = 1 << 1, [HITRACE_FLAG_TP_INFO](_hitrace.md) = 1 << 2,<br>[HITRACE_FLAG_NO_BE_INFO](_hitrace.md) = 1 << 3, [HITRACE_FLAG_DONOT_ENABLE_LOG](_hitrace.md) = 1 << 4, [HITRACE_FLAG_FAULT_TRIGGER](_hitrace.md) = 1 << 5, [HITRACE_FLAG_D2D_TP_INFO](_hitrace.md) = 1 << 6<br>} | Enumerates the HiTrace flags. | 99| [HiTrace_Tracepoint_Type](_hitrace.md#hitrace_tracepoint_type) {<br>[HITRACE_TP_CS](_hitrace.md) = 0, [HITRACE_TP_CR](_hitrace.md) = 1, [HITRACE_TP_SS](_hitrace.md) = 2, [HITRACE_TP_SR](_hitrace.md) = 3,<br>[HITRACE_TP_GENERAL](_hitrace.md) = 4<br>} | Enumerates the HiTrace tracepoint types. | 100| [HiTrace_Communication_Mode](_hitrace.md#hitrace_communication_mode) { [HITRACE_CM_DEFAULT](_hitrace.md) = 0, [HITRACE_CM_THREAD](_hitrace.md) = 1, [HITRACE_CM_PROCESS](_hitrace.md) = 2, [HITRACE_CM_DEVICE](_hitrace.md) = 3 } | Enumerates the HiTrace communication modes. | 101 102 103### Functions 104 105| Name| Description| 106| -------- | -------- | 107| [HiTraceId](_hi_trace_id.md) [OH_HiTrace_BeginChain](_hitrace.md#oh_hitrace_beginchain) (const char \*name, int flags) | Starts tracing a process. | 108| void [OH_HiTrace_EndChain](_hitrace.md#oh_hitrace_endchain) () | Stops tracing the process and clears the trace ID of the calling thread if the given trace ID is valid. Otherwise, no operation is performed. | 109| [HiTraceId](_hi_trace_id.md) [OH_HiTrace_GetId](_hitrace.md#oh_hitrace_getid) () | Obtains the trace ID of the calling thread. If the calling thread does not have a trace ID, an invalid trace ID is returned. | 110| void [OH_HiTrace_SetId](_hitrace.md#oh_hitrace_setid) (const [HiTraceId](_hi_trace_id.md) \*id) | Sets the trace ID of the calling thread. If the ID is invalid, no operation is performed. | 111| void [OH_HiTrace_ClearId](_hitrace.md#oh_hitrace_clearid) (void) | Clears the trace ID of the calling thread and invalidates it. | 112| [HiTraceId](_hi_trace_id.md) [OH_HiTrace_CreateSpan](_hitrace.md#oh_hitrace_createspan) (void) | Creates a span ID based on the trace ID of the calling thread. | 113| void [OH_HiTrace_Tracepoint](_hitrace.md#oh_hitrace_tracepoint) ([HiTrace_Communication_Mode](_hitrace.md#hitrace_communication_mode) mode, [HiTrace_Tracepoint_Type](_hitrace.md#hitrace_tracepoint_type) type, const [HiTraceId](_hi_trace_id.md) \*id, const char \*fmt,...) | Prints HiTrace information, including the trace ID. | 114| void [OH_HiTrace_InitId](_hitrace.md#oh_hitrace_initid) ([HiTraceId](_hi_trace_id.md) \*id) | Initializes a **HiTraceId** instance. | 115| void [OH_HiTrace_IdFromBytes](_hitrace.md#oh_hitrace_idfrombytes) ([HiTraceId](_hi_trace_id.md) \*id, const uint8_t \*pIdArray, int len) | Creates a **HiTraceId** instance based on a byte array. | 116| bool [OH_HiTrace_IsIdValid](_hitrace.md#oh_hitrace_isidvalid) (const [HiTraceId](_hi_trace_id.md) \*id) | Checks whether a **HiTraceId** instance is valid. | 117| bool [OH_HiTrace_IsFlagEnabled](_hitrace.md#oh_hitrace_isflagenabled) (const [HiTraceId](_hi_trace_id.md) \*id, [HiTrace_Flag](_hitrace.md#hitrace_flag) flag) | Checks whether the specified trace flag is enabled in a **HiTraceId** instance. | 118| void [OH_HiTrace_EnableFlag](_hitrace.md#oh_hitrace_enableflag) (const [HiTraceId](_hi_trace_id.md) \*id, [HiTrace_Flag](_hitrace.md#hitrace_flag) flag) | Enables the specified trace flag in a **HiTraceId** instance. | 119| int [OH_HiTrace_GetFlags](_hitrace.md#oh_hitrace_getflags) (const [HiTraceId](_hi_trace_id.md) \*id) | Obtains the trace flags in a **HiTraceId** instance. | 120| void [OH_HiTrace_SetFlags](_hitrace.md#oh_hitrace_setflags) ([HiTraceId](_hi_trace_id.md) \*id, int flags) | Sets trace flags in a **HiTraceId** instance. | 121| uint64_t [OH_HiTrace_GetChainId](_hitrace.md#oh_hitrace_getchainid) (const [HiTraceId](_hi_trace_id.md) \*id) | Obtains a trace chain ID. | 122| void [OH_HiTrace_SetChainId](_hitrace.md#oh_hitrace_setchainid) ([HiTraceId](_hi_trace_id.md) \*id, uint64_t chainId) | Sets the trace chain ID in a **HiTraceId** instance. | 123| uint64_t [OH_HiTrace_GetSpanId](_hitrace.md#oh_hitrace_getspanid) (const [HiTraceId](_hi_trace_id.md) \*id) | Obtains the span ID in a **HiTraceId** instance. | 124| void [OH_HiTrace_SetSpanId](_hitrace.md#oh_hitrace_setspanid) ([HiTraceId](_hi_trace_id.md) \*id, uint64_t spanId) | Sets the span ID in a **HiTraceId** instance. | 125| uint64_t [OH_HiTrace_GetParentSpanId](_hitrace.md#oh_hitrace_getparentspanid) (const [HiTraceId](_hi_trace_id.md) \*id) | Obtains the parent span ID in a **HiTraceId** instance. | 126| void [OH_HiTrace_SetParentSpanId](_hitrace.md#oh_hitrace_setparentspanid) ([HiTraceId](_hi_trace_id.md) \*id, uint64_t parentSpanId) | Sets the **ParentSpanId** in a **HiTraceId** instance. | 127| int [OH_HiTrace_IdToBytes](_hitrace.md#oh_hitrace_idtobytes) (const [HiTraceId](_hi_trace_id.md) \*id, uint8_t \*pIdArray, int len) | Converts a **HiTraceId** instance into a byte array for caching or transfer. | 128| void [OH_HiTrace_StartTrace](_hitrace.md#oh_hitrace_starttrace) (const char \*name) | Marks the start of a synchronous trace. | 129| void [OH_HiTrace_FinishTrace](_hitrace.md#oh_hitrace_finishtrace) (void) | Marks the end of a synchronous trace. | 130| void [OH_HiTrace_StartAsyncTrace](_hitrace.md#oh_hitrace_startasynctrace) (const char \*name, int32_t taskId) | Marks the start of an asynchronous trace. | 131| void [OH_HiTrace_FinishAsyncTrace](_hitrace.md#oh_hitrace_finishasynctrace) (const char \*name, int32_t taskId) | Marks the end of an asynchronous trace. | 132| void [OH_HiTrace_CountTrace](_hitrace.md#oh_hitrace_counttrace) (const char \*name, int64_t count) | Traces the value change of an integer variable based on its name. | 133