setup.c: support multi-checkout repo setup

diff --git a/git.c b/git.c
index fac390233c69c5300db4439160f7d8ebea6b7fd2..18fbf79430687a473e9306f2bb65abbaec161bb4 100644 (file)
--- a/git.c
+++ b/git.c
@@ -14,7 +14,7 @@ const char git_usage_string[] =
        "           <command> [<args>]";
 
 const char git_more_info_string[] =
-       N_("'git help -a' and 'git help -g' lists available subcommands and some\n"
+       N_("'git help -a' and 'git help -g' list available subcommands and some\n"
           "concept guides. See 'git help <command>' or 'git help <concept>'\n"
           "to read about a specific subcommand or concept.");
 
@@ -282,8 +282,7 @@ static int handle_alias(int *argcp, const char ***argv)
                                  "trace: alias expansion: %s =>",
                                  alias_command);
 
-               new_argv = xrealloc(new_argv, sizeof(char *) *
-                                   (count + *argcp));
+               REALLOC_ARRAY(new_argv, count + *argcp);
                /* insert after command name */
                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 
@@ -594,6 +593,26 @@ static int run_argv(int *argcp, const char ***argv)
        return done_alias;
 }
 
+/*
+ * Many parts of Git have subprograms communicate via pipe, expect the
+ * upstream of a pipe to die with SIGPIPE when the downstream of a
+ * pipe does not need to read all that is written.  Some third-party
+ * programs that ignore or block SIGPIPE for their own reason forget
+ * to restore SIGPIPE handling to the default before spawning Git and
+ * break this carefully orchestrated machinery.
+ *
+ * Restore the way SIGPIPE is handled to default, which is what we
+ * expect.
+ */
+static void restore_sigpipe_to_default(void)
+{
+       sigset_t unblock;
+
+       sigemptyset(&unblock);
+       sigaddset(&unblock, SIGPIPE);
+       sigprocmask(SIG_UNBLOCK, &unblock, NULL);
+       signal(SIGPIPE, SIG_DFL);
+}
 
 int main(int argc, char **av)
 {
@@ -613,6 +632,8 @@ int main(int argc, char **av)
         */
        sanitize_stdfds();
 
+       restore_sigpipe_to_default();
+
        git_setup_gettext();
 
        trace_command_performance(argv);