git/trace2.h
SZEDER Gábor e4b75d6a1d trace2: rename environment variables to GIT_TRACE2*
For an environment variable that is supposed to be set by users, the
GIT_TR2* env vars are just too unclear, inconsistent, and ugly.

Most of the established GIT_* environment variables don't use
abbreviations, and in case of the few that do (GIT_DIR,
GIT_COMMON_DIR, GIT_DIFF_OPTS) it's quite obvious what the
abbreviations (DIR and OPTS) stand for.  But what does TR stand for?
Track, traditional, trailer, transaction, transfer, transformation,
transition, translation, transplant, transport, traversal, tree,
trigger, truncate, trust, or ...?!

The trace2 facility, as the '2' suffix in its name suggests, is
supposed to eventually supercede Git's original trace facility.  It's
reasonable to expect that the corresponding environment variables
follow suit, and after the original GIT_TRACE variables they are
called GIT_TRACE2; there is no such thing is 'GIT_TR'.

All trace2-specific config variables are, very sensibly, in the
'trace2' section, not in 'tr2'.

OTOH, we don't gain anything at all by omitting the last three
characters of "trace" from the names of these environment variables.

So let's rename all GIT_TR2* environment variables to GIT_TRACE2*,
before they make their way into a stable release.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-05-28 10:20:34 -07:00

411 lines
14 KiB
C

#ifndef TRACE2_H
#define TRACE2_H
struct child_process;
struct repository;
struct json_writer;
/*
* The public TRACE2 routines are grouped into the following groups:
*
* [] trace2_initialize -- initialization.
* [] trace2_cmd_* -- emit command/control messages.
* [] trace2_child* -- emit child start/stop messages.
* [] trace2_exec* -- emit exec start/stop messages.
* [] trace2_thread* -- emit thread start/stop messages.
* [] trace2_def* -- emit definition/parameter mesasges.
* [] trace2_region* -- emit region nesting messages.
* [] trace2_data* -- emit region/thread/repo data messages.
* [] trace2_printf* -- legacy trace[1] messages.
*/
/*
* Initialize the TRACE2 clock and do nothing else, in particular
* no mallocs, no system inspection, and no environment inspection.
*
* This should be called at the very top of main() to capture the
* process start time. This is intended to reduce chicken-n-egg
* bootstrap pressure.
*
* It is safe to call this more than once. This allows capturing
* absolute startup costs on Windows which uses a little trickery
* to do setup work before common-main.c:main() is called.
*
* The main trace2_initialize_fl() may be called a little later
* after more infrastructure is established.
*/
void trace2_initialize_clock(void);
/*
* Initialize TRACE2 tracing facility if any of the builtin TRACE2
* targets are enabled in the system config or the environment.
* Emits a 'version' event.
*
* Cleanup/Termination is handled automatically by a registered
* atexit() routine.
*/
void trace2_initialize_fl(const char *file, int line);
#define trace2_initialize() trace2_initialize_fl(__FILE__, __LINE__)
/*
* Return true if trace2 is enabled.
*/
int trace2_is_enabled(void);
/*
* Emit a 'start' event with the original (unmodified) argv.
*/
void trace2_cmd_start_fl(const char *file, int line, const char **argv);
#define trace2_cmd_start(argv) trace2_cmd_start_fl(__FILE__, __LINE__, (argv))
/*
* Emit an 'exit' event.
*
* Write the exit-code that will be passed to exit() or returned
* from main().
*
* Use this prior to actually calling exit().
* See "#define exit()" in git-compat-util.h
*/
int trace2_cmd_exit_fl(const char *file, int line, int code);
#define trace2_cmd_exit(code) (trace2_cmd_exit_fl(__FILE__, __LINE__, (code)))
/*
* Emit an 'error' event.
*
* Write an error message to the TRACE2 targets.
*/
void trace2_cmd_error_va_fl(const char *file, int line, const char *fmt,
va_list ap);
#define trace2_cmd_error_va(fmt, ap) \
trace2_cmd_error_va_fl(__FILE__, __LINE__, (fmt), (ap))
/*
* Emit a 'pathname' event with the canonical pathname of the current process
* This gives post-processors a simple field to identify the command without
* having to parse the argv. For example, to distinguish invocations from
* installed versus debug executables.
*/
void trace2_cmd_path_fl(const char *file, int line, const char *pathname);
#define trace2_cmd_path(p) trace2_cmd_path_fl(__FILE__, __LINE__, (p))
/*
* Emit a 'cmd_name' event with the canonical name of the command.
* This gives post-processors a simple field to identify the command
* without having to parse the argv.
*/
void trace2_cmd_name_fl(const char *file, int line, const char *name);
#define trace2_cmd_name(v) trace2_cmd_name_fl(__FILE__, __LINE__, (v))
/*
* Emit a 'cmd_mode' event to further describe the command being run.
* For example, "checkout" can checkout a single file or can checkout a
* different branch. This gives post-processors a simple field to compare
* equivalent commands without having to parse the argv.
*/
void trace2_cmd_mode_fl(const char *file, int line, const char *mode);
#define trace2_cmd_mode(sv) trace2_cmd_mode_fl(__FILE__, __LINE__, (sv))
/*
* Emit an 'alias' expansion event.
*/
void trace2_cmd_alias_fl(const char *file, int line, const char *alias,
const char **argv);
#define trace2_cmd_alias(alias, argv) \
trace2_cmd_alias_fl(__FILE__, __LINE__, (alias), (argv))
/*
* Emit one or more 'def_param' events for "interesting" configuration
* settings.
*
* Use the TR2_SYSENV_CFG_PARAM setting to register a comma-separated
* list of patterns configured important. For example:
* git config --system trace2.configParams 'core.*,remote.*.url'
* or:
* GIT_TRACE2_CONFIG_PARAMS=core.*,remote.*.url"
*
* Note: this routine does a read-only iteration on the config data
* (using read_early_config()), so it must not be called until enough
* of the process environment has been established. This includes the
* location of the git and worktree directories, expansion of any "-c"
* and "-C" command line options, and etc.
*/
void trace2_cmd_list_config_fl(const char *file, int line);
#define trace2_cmd_list_config() trace2_cmd_list_config_fl(__FILE__, __LINE__)
/*
* Emit a "def_param" event for the given config key/value pair IF
* we consider the key to be "interesting".
*
* Use this for new/updated config settings created/updated after
* trace2_cmd_list_config() is called.
*/
void trace2_cmd_set_config_fl(const char *file, int line, const char *key,
const char *value);
#define trace2_cmd_set_config(k, v) \
trace2_cmd_set_config_fl(__FILE__, __LINE__, (k), (v))
/*
* Emit a 'child_start' event prior to spawning a child process.
*
* Before calling optionally set "cmd->trace2_child_class" to a string
* describing the type of the child process. For example, "editor" or
* "pager".
*/
void trace2_child_start_fl(const char *file, int line,
struct child_process *cmd);
#define trace2_child_start(cmd) trace2_child_start_fl(__FILE__, __LINE__, (cmd))
/*
* Emit a 'child_exit' event after the child process completes.
*/
void trace2_child_exit_fl(const char *file, int line, struct child_process *cmd,
int child_exit_code);
#define trace2_child_exit(cmd, code) \
trace2_child_exit_fl(__FILE__, __LINE__, (cmd), (code))
/*
* Emit an 'exec' event prior to calling one of exec(), execv(),
* execvp(), and etc. On Unix-derived systems, this will be the
* last event emitted for the current process, unless the exec
* fails. On Windows, exec() behaves like 'child_start' and a
* waitpid(), so additional events may be emitted.
*
* Returns the "exec_id".
*/
int trace2_exec_fl(const char *file, int line, const char *exe,
const char **argv);
#define trace2_exec(exe, argv) trace2_exec_fl(__FILE__, __LINE__, (exe), (argv))
/*
* Emit an 'exec_result' when possible. On Unix-derived systems,
* this should be called after exec() returns (which only happens
* when there is an error starting the new process). On Windows,
* this should be called after the waitpid().
*
* The "exec_id" should be the value returned from trace2_exec().
*/
void trace2_exec_result_fl(const char *file, int line, int exec_id, int code);
#define trace2_exec_result(id, code) \
trace2_exec_result_fl(__FILE__, __LINE__, (id), (code))
/*
* Emit a 'thread_start' event. This must be called from inside the
* thread-proc to set up the trace2 TLS data for the thread.
*
* Thread names should be descriptive, like "preload_index".
* Thread names will be decorated with an instance number automatically.
*/
void trace2_thread_start_fl(const char *file, int line,
const char *thread_name);
#define trace2_thread_start(thread_name) \
trace2_thread_start_fl(__FILE__, __LINE__, (thread_name))
/*
* Emit a 'thread_exit' event. This must be called from inside the
* thread-proc to report thread-specific data and cleanup TLS data
* for the thread.
*/
void trace2_thread_exit_fl(const char *file, int line);
#define trace2_thread_exit() trace2_thread_exit_fl(__FILE__, __LINE__)
/*
* Emit a 'param' event.
*
* Write a "<param> = <value>" pair describing some aspect of the
* run such as an important configuration setting or command line
* option that significantly changes command behavior.
*/
void trace2_def_param_fl(const char *file, int line, const char *param,
const char *value);
#define trace2_def_param(param, value) \
trace2_def_param_fl(__FILE__, __LINE__, (param), (value))
/*
* Tell trace2 about a newly instantiated repo object and assign
* a trace2-repo-id to be used in subsequent activity events.
*
* Emits a 'worktree' event for this repo instance.
*/
void trace2_def_repo_fl(const char *file, int line, struct repository *repo);
#define trace2_def_repo(repo) trace2_def_repo_fl(__FILE__, __LINE__, repo)
/*
* Emit a 'region_enter' event for <category>.<label> with optional
* repo-id and printf message.
*
* Enter a new nesting level on the current thread and remember the
* current time. This controls the indenting of all subsequent events
* on this thread.
*/
void trace2_region_enter_fl(const char *file, int line, const char *category,
const char *label, const struct repository *repo, ...);
#define trace2_region_enter(category, label, repo) \
trace2_region_enter_fl(__FILE__, __LINE__, (category), (label), (repo))
void trace2_region_enter_printf_va_fl(const char *file, int line,
const char *category, const char *label,
const struct repository *repo,
const char *fmt, va_list ap);
#define trace2_region_enter_printf_va(category, label, repo, fmt, ap) \
trace2_region_enter_printf_va_fl(__FILE__, __LINE__, (category), \
(label), (repo), (fmt), (ap))
void trace2_region_enter_printf_fl(const char *file, int line,
const char *category, const char *label,
const struct repository *repo,
const char *fmt, ...);
#ifdef HAVE_VARIADIC_MACROS
#define trace2_region_enter_printf(category, label, repo, ...) \
trace2_region_enter_printf_fl(__FILE__, __LINE__, (category), (label), \
(repo), __VA_ARGS__)
#else
/* clang-format off */
__attribute__((format (region_enter_printf, 4, 5)))
void trace2_region_enter_printf(const char *category, const char *label,
const struct repository *repo, const char *fmt,
...);
/* clang-format on */
#endif
/*
* Emit a 'region_leave' event for <category>.<label> with optional
* repo-id and printf message.
*
* Leave current nesting level and report the elapsed time spent
* in this nesting level.
*/
void trace2_region_leave_fl(const char *file, int line, const char *category,
const char *label, const struct repository *repo, ...);
#define trace2_region_leave(category, label, repo) \
trace2_region_leave_fl(__FILE__, __LINE__, (category), (label), (repo))
void trace2_region_leave_printf_va_fl(const char *file, int line,
const char *category, const char *label,
const struct repository *repo,
const char *fmt, va_list ap);
#define trace2_region_leave_printf_va(category, label, repo, fmt, ap) \
trace2_region_leave_printf_va_fl(__FILE__, __LINE__, (category), \
(label), (repo), (fmt), (ap))
void trace2_region_leave_printf_fl(const char *file, int line,
const char *category, const char *label,
const struct repository *repo,
const char *fmt, ...);
#ifdef HAVE_VARIADIC_MACROS
#define trace2_region_leave_printf(category, label, repo, ...) \
trace2_region_leave_printf_fl(__FILE__, __LINE__, (category), (label), \
(repo), __VA_ARGS__)
#else
/* clang-format off */
__attribute__((format (region_leave_printf, 4, 5)))
void trace2_region_leave_printf(const char *category, const char *label,
const struct repository *repo, const char *fmt,
...);
/* clang-format on */
#endif
/*
* Emit a key-value pair 'data' event of the form <category>.<key> = <value>.
* This event implicitly contains information about thread, nesting region,
* and optional repo-id.
*
* On event-based TRACE2 targets, this generates a 'data' event suitable
* for post-processing. On printf-based TRACE2 targets, this is converted
* into a fixed-format printf message.
*/
void trace2_data_string_fl(const char *file, int line, const char *category,
const struct repository *repo, const char *key,
const char *value);
#define trace2_data_string(category, repo, key, value) \
trace2_data_string_fl(__FILE__, __LINE__, (category), (repo), (key), \
(value))
void trace2_data_intmax_fl(const char *file, int line, const char *category,
const struct repository *repo, const char *key,
intmax_t value);
#define trace2_data_intmax(category, repo, key, value) \
trace2_data_intmax_fl(__FILE__, __LINE__, (category), (repo), (key), \
(value))
void trace2_data_json_fl(const char *file, int line, const char *category,
const struct repository *repo, const char *key,
const struct json_writer *jw);
#define trace2_data_json(category, repo, key, value) \
trace2_data_json_fl(__FILE__, __LINE__, (category), (repo), (key), \
(value))
/*
* Emit a 'printf' event.
*
* Write an arbitrary formatted message to the TRACE2 targets. These
* text messages should be considered as human-readable strings without
* any formatting guidelines. Post-processors may choose to ignore
* them.
*/
void trace2_printf_va_fl(const char *file, int line, const char *fmt,
va_list ap);
#define trace2_printf_va(fmt, ap) \
trace2_printf_va_fl(__FILE__, __LINE__, (fmt), (ap))
void trace2_printf_fl(const char *file, int line, const char *fmt, ...);
#ifdef HAVE_VARIADIC_MACROS
#define trace2_printf(...) trace2_printf_fl(__FILE__, __LINE__, __VA_ARGS__)
#else
/* clang-format off */
__attribute__((format (printf, 1, 2)))
void trace2_printf(const char *fmt, ...);
/* clang-format on */
#endif
/*
* Optional platform-specific code to dump information about the
* current and any parent process(es). This is intended to allow
* post-processors to know who spawned this git instance and anything
* else that the platform may be able to tell us about the current process.
*/
enum trace2_process_info_reason {
TRACE2_PROCESS_INFO_STARTUP,
TRACE2_PROCESS_INFO_EXIT,
};
#if defined(GIT_WINDOWS_NATIVE)
void trace2_collect_process_info(enum trace2_process_info_reason reason);
#else
#define trace2_collect_process_info(reason) \
do { \
} while (0)
#endif
#endif /* TRACE2_H */