git/trace2/tr2_cfg.c
Jeff Hostetler bce9db6de9 trace2: use system/global config for default trace2 settings
Teach git to read the system and global config files for
default Trace2 settings.  This allows system-wide Trace2 settings to
be installed and inherited to make it easier to manage a collection of
systems.

The original GIT_TR2* environment variables are loaded afterwards and
can be used to override the system settings.

Only the system and global config files are used.  Repo and worktree
local config files are ignored.  Likewise, the "-c" command line
arguments are also ignored.  These limits are for performance reasons.

(1) For users not using Trace2, there should be minimal overhead to
detect that Trace2 is not enabled.  In particular, Trace2 should not
allocate lots of otherwise unused data strucutres.

(2) For accurate performance measurements, Trace2 should be initialized
as early in the git process as possible, and before most of the normal
git process initialization (which involves discovering the .git directory
and reading a hierarchy of config files).

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-04-16 13:37:06 +09:00

89 lines
2 KiB
C

#include "cache.h"
#include "config.h"
#include "trace2/tr2_cfg.h"
#include "trace2/tr2_sysenv.h"
static struct strbuf **tr2_cfg_patterns;
static int tr2_cfg_count_patterns;
static int tr2_cfg_loaded;
/*
* Parse a string containing a comma-delimited list of config keys
* or wildcard patterns into a list of strbufs.
*/
static int tr2_cfg_load_patterns(void)
{
struct strbuf **s;
const char *envvar;
if (tr2_cfg_loaded)
return tr2_cfg_count_patterns;
tr2_cfg_loaded = 1;
envvar = tr2_sysenv_get(TR2_SYSENV_CFG_PARAM);
if (!envvar || !*envvar)
return tr2_cfg_count_patterns;
tr2_cfg_patterns = strbuf_split_buf(envvar, strlen(envvar), ',', -1);
for (s = tr2_cfg_patterns; *s; s++) {
struct strbuf *buf = *s;
if (buf->len && buf->buf[buf->len - 1] == ',')
strbuf_setlen(buf, buf->len - 1);
strbuf_trim_trailing_newline(*s);
strbuf_trim(*s);
}
tr2_cfg_count_patterns = s - tr2_cfg_patterns;
return tr2_cfg_count_patterns;
}
void tr2_cfg_free_patterns(void)
{
if (tr2_cfg_patterns)
strbuf_list_free(tr2_cfg_patterns);
tr2_cfg_count_patterns = 0;
tr2_cfg_loaded = 0;
}
struct tr2_cfg_data {
const char *file;
int line;
};
/*
* See if the given config key matches any of our patterns of interest.
*/
static int tr2_cfg_cb(const char *key, const char *value, void *d)
{
struct strbuf **s;
struct tr2_cfg_data *data = (struct tr2_cfg_data *)d;
for (s = tr2_cfg_patterns; *s; s++) {
struct strbuf *buf = *s;
int wm = wildmatch(buf->buf, key, WM_CASEFOLD);
if (wm == WM_MATCH) {
trace2_def_param_fl(data->file, data->line, key, value);
return 0;
}
}
return 0;
}
void tr2_cfg_list_config_fl(const char *file, int line)
{
struct tr2_cfg_data data = { file, line };
if (tr2_cfg_load_patterns() > 0)
read_early_config(tr2_cfg_cb, &data);
}
void tr2_cfg_set_fl(const char *file, int line, const char *key,
const char *value)
{
struct tr2_cfg_data data = { file, line };
if (tr2_cfg_load_patterns() > 0)
tr2_cfg_cb(key, value, &data);
}