Re: [PATCH] Fix signal handler
- From
- Markus Elfring <markus.elfring@web.de>
- Date
- Feb 10, 2010, 17:08 UTC
- Message-ID
- <4B72E81B.3020900@web.de>
- In-Reply-To
- <4B71A2EE.8070708@web.de>
Hello,
How do Git software developers think about the appended update suggestion? Would you like to integrate such adjustments into your source code repository?
Regards, Markus
>From c37d8dafef11168d8302d40c8d1453943a058d95 Mon Sep 17 00:00:00 2001
From: Markus Elfring <Markus.Elfring@web.de> Date: Wed, 10 Feb 2010 17:05:45 +0100 Subject: [PATCH] Fix a signal handler
A global flag can only be set by a signal handler in a portable way if it has got the data type "sig_atomic_t". The previously used assignment of a function pointer in the function "early_output" was moved to another variable in the function "setup_early_output". The involved software design details were also mentioned on the mailing list. --- builtin-log.c | 12 +++--------- revision.c | 14 ++++++-------- revision.h | 3 ++- 3 files changed, 11 insertions(+), 18 deletions(-)
diff --git a/builtin-log.c b/builtin-log.c index 8d16832..358c98b 100644 --- a/builtin-log.c +++ b/builtin-log.c @@ -123,7 +123,7 @@ static void show_early_header(struct rev_info *rev, const char *stage, int nr) static struct itimerval early_output_timer; -static void log_show_early(struct rev_info *revs, struct commit_list *list) +extern void log_show_early(struct rev_info *revs, struct commit_list *list) { int i = revs->early_output; int show_header = 1; @@ -170,20 +170,14 @@ static void log_show_early(struct rev_info *revs, struct commit_list *list) static void early_output(int signal) { - show_early_output = log_show_early; + show_early_output = 1; } static void setup_early_output(struct rev_info *rev) { struct sigaction sa; - /* - * Set up the signal handler, minimally intrusively: - * we only set a single volatile integer word (not - * using sigatomic_t - trying to avoid unnecessary - * system dependencies and headers), and using - * SA_RESTART. - */ + early_output_function = &log_show_early; memset(&sa, 0, sizeof(sa)); sa.sa_handler = early_output; sigemptyset(&sa.sa_mask); diff --git a/revision.c b/revision.c index 3ba6d99..62402fb 100644 --- a/revision.c +++ b/revision.c @@ -13,7 +13,8 @@ #include "decorate.h" #include "log-tree.h" -volatile show_early_output_fn_t show_early_output; +sig_atomic_t show_early_output = 0; +show_early_output_fn_t early_output_function = NULL; char *path_name(const struct name_path *path, const char *name) { @@ -654,7 +655,6 @@ static int limit_list(struct rev_info *revs) struct commit_list *entry = list; struct commit *commit = list->item; struct object *obj = &commit->object; - show_early_output_fn_t show; list = list->next; free(entry); @@ -680,12 +680,10 @@ static int limit_list(struct rev_info *revs) date = commit->date; p = &commit_list_insert(commit, p)->next; - show = show_early_output; - if (!show) - continue; - - show(revs, newlist); - show_early_output = NULL; + if (show_early_output) { + (*early_output_function)(revs, newlist); + show_early_output = 0; + } } if (revs->cherry_pick) cherry_pick_list(newlist, revs); diff --git a/revision.h b/revision.h index a14deef..93a8ffc 100644 --- a/revision.h +++ b/revision.h @@ -135,7 +135,8 @@ struct rev_info { /* revision.c */ typedef void (*show_early_output_fn_t)(struct rev_info *, struct commit_list *); -extern volatile show_early_output_fn_t show_early_output; +extern show_early_output_fn_t early_output_function; +extern sig_atomic_t show_early_output; extern void init_revisions(struct rev_info *revs, const char *prefix); extern int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def);
-- 1.6.6.1