tracy/zstd/common/zstd_trace.h
2023-02-10 20:33:32 +01:00

164 lines
4.5 KiB
C

/*
* Copyright (c) Meta Platforms, Inc. and affiliates.
* All rights reserved.
*
* This source code is licensed under both the BSD-style license (found in the
* LICENSE file in the root directory of this source tree) and the GPLv2 (found
* in the COPYING file in the root directory of this source tree).
* You may select, at your option, one of the above-listed licenses.
*/
#ifndef ZSTD_TRACE_H
#define ZSTD_TRACE_H
#if defined (__cplusplus)
extern "C" {
#endif
#include <stddef.h>
/* weak symbol support
* For now, enable conservatively:
* - Only GNUC
* - Only ELF
* - Only x86-64, i386 and aarch64
* Also, explicitly disable on platforms known not to work so they aren't
* forgotten in the future.
*/
#if !defined(ZSTD_HAVE_WEAK_SYMBOLS) && \
defined(__GNUC__) && defined(__ELF__) && \
(defined(__x86_64__) || defined(_M_X64) || defined(__i386__) || defined(_M_IX86) || defined(__aarch64__)) && \
!defined(__APPLE__) && !defined(_WIN32) && !defined(__MINGW32__) && \
!defined(__CYGWIN__) && !defined(_AIX)
# define ZSTD_HAVE_WEAK_SYMBOLS 1
#else
# define ZSTD_HAVE_WEAK_SYMBOLS 0
#endif
#if ZSTD_HAVE_WEAK_SYMBOLS
# define ZSTD_WEAK_ATTR __attribute__((__weak__))
#else
# define ZSTD_WEAK_ATTR
#endif
/* Only enable tracing when weak symbols are available. */
#ifndef ZSTD_TRACE
# define ZSTD_TRACE ZSTD_HAVE_WEAK_SYMBOLS
#endif
#if ZSTD_TRACE
struct ZSTD_CCtx_s;
struct ZSTD_DCtx_s;
struct ZSTD_CCtx_params_s;
typedef struct {
/**
* ZSTD_VERSION_NUMBER
*
* This is guaranteed to be the first member of ZSTD_trace.
* Otherwise, this struct is not stable between versions. If
* the version number does not match your expectation, you
* should not interpret the rest of the struct.
*/
unsigned version;
/**
* Non-zero if streaming (de)compression is used.
*/
unsigned streaming;
/**
* The dictionary ID.
*/
unsigned dictionaryID;
/**
* Is the dictionary cold?
* Only set on decompression.
*/
unsigned dictionaryIsCold;
/**
* The dictionary size or zero if no dictionary.
*/
size_t dictionarySize;
/**
* The uncompressed size of the data.
*/
size_t uncompressedSize;
/**
* The compressed size of the data.
*/
size_t compressedSize;
/**
* The fully resolved CCtx parameters (NULL on decompression).
*/
struct ZSTD_CCtx_params_s const* params;
/**
* The ZSTD_CCtx pointer (NULL on decompression).
*/
struct ZSTD_CCtx_s const* cctx;
/**
* The ZSTD_DCtx pointer (NULL on compression).
*/
struct ZSTD_DCtx_s const* dctx;
} ZSTD_Trace;
/**
* A tracing context. It must be 0 when tracing is disabled.
* Otherwise, any non-zero value returned by a tracing begin()
* function is presented to any subsequent calls to end().
*
* Any non-zero value is treated as tracing is enabled and not
* interpreted by the library.
*
* Two possible uses are:
* * A timestamp for when the begin() function was called.
* * A unique key identifying the (de)compression, like the
* address of the [dc]ctx pointer if you need to track
* more information than just a timestamp.
*/
typedef unsigned long long ZSTD_TraceCtx;
/**
* Trace the beginning of a compression call.
* @param cctx The dctx pointer for the compression.
* It can be used as a key to map begin() to end().
* @returns Non-zero if tracing is enabled. The return value is
* passed to ZSTD_trace_compress_end().
*/
ZSTD_WEAK_ATTR ZSTD_TraceCtx ZSTD_trace_compress_begin(
struct ZSTD_CCtx_s const* cctx);
/**
* Trace the end of a compression call.
* @param ctx The return value of ZSTD_trace_compress_begin().
* @param trace The zstd tracing info.
*/
ZSTD_WEAK_ATTR void ZSTD_trace_compress_end(
ZSTD_TraceCtx ctx,
ZSTD_Trace const* trace);
/**
* Trace the beginning of a decompression call.
* @param dctx The dctx pointer for the decompression.
* It can be used as a key to map begin() to end().
* @returns Non-zero if tracing is enabled. The return value is
* passed to ZSTD_trace_compress_end().
*/
ZSTD_WEAK_ATTR ZSTD_TraceCtx ZSTD_trace_decompress_begin(
struct ZSTD_DCtx_s const* dctx);
/**
* Trace the end of a decompression call.
* @param ctx The return value of ZSTD_trace_decompress_begin().
* @param trace The zstd tracing info.
*/
ZSTD_WEAK_ATTR void ZSTD_trace_decompress_end(
ZSTD_TraceCtx ctx,
ZSTD_Trace const* trace);
#endif /* ZSTD_TRACE */
#if defined (__cplusplus)
}
#endif
#endif /* ZSTD_TRACE_H */