undef/git-commit-vandalism
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

run-command: provide in_async query function

Browse Source 
It's not easy for arbitrary code to find out whether it is
running in an async process or not. A top-level function
which is fed to start_async() can know (you just pass down
an argument saying "you are async"). But that function may
call other global functions, and we would not want to have
to pass the information all the way through the call stack.

Nor can we simply set a global variable, as those may be
shared between async threads and the main thread (if the
platform supports pthreads). We need pthread tricks _or_ a
global variable, depending on how start_async is
implemented.

The callers don't have enough information to do this right,
so let's provide a simple query function that does.
Fortunately we can reuse the existing infrastructure to make
the pthread case simple (and even simplify die_async() by
using our new function).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Jeff King 2015-09-01 16:22:43 -04:00 committed by Junio C Hamano
parent 323598387d
commit 661a8cf408
2 changed files with 16 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
run-command.c
View File

@ -608,7 +608,7 @@ static NORETURN void die_async(const char *err, va_list params)
{
vreportf("fatal: ", err, params);
if (!pthread_equal(main_thread, pthread_self())) {
if (in_async()) {
struct async *async = pthread_getspecific(async_key);
if (async->proc_in >= 0)
close(async->proc_in);
@ -627,6 +627,13 @@ static int async_die_is_recursing(void)
return ret != NULL;
}
int in_async(void)
{
if (!main_thread_set)
return 0; /* no asyncs started yet */
return !pthread_equal(main_thread, pthread_self());
}
#else
static struct {
@ -666,6 +673,12 @@ int git_atexit(void (*handler)(void))
}
#define atexit git_atexit
static int process_is_async;
int in_async(void)
{
return process_is_async;
}
#endif
int start_async(struct async *async)
@ -725,6 +738,7 @@ int start_async(struct async *async)
if (need_out)
close(fdout[0]);
git_atexit_clear();
process_is_async = 1;
exit(!!async->proc(proc_in, proc_out, async->data));
}

1
run-command.h
View File

@ -113,5 +113,6 @@ struct async {
int start_async(struct async *async);
int finish_async(struct async *async);
int in_async(void);
#endif