Re: [PATCH] pager: exit without error on SIGPIPE

[Johannes Sixt <j6t@kdbg.org>]

Am 30.01.21 um 09:29 schrieb Johannes Sixt:
> Am 30.01.21 um 00:48 schrieb Denton Liu:
>> +++ b/t/helper/test-pager.c
>> @@ -0,0 +1,12 @@
>> +#include "test-tool.h"
>> +#include "cache.h"
>> +
>> +int cmd__pager(int argc, const char **argv)
>> +{
>> +	if (argc > 1)
>> +		usage("\ttest-tool pager");
>> +
>> +	setup_pager();
>> +	for (;;)
>> +		puts("y");
>> +}
> 
> My gut feeling tells that this will end in an infinite loop on Windows.
> There are no signals on Windows that would kill the upstream of a pipe.
> This call site will only notice that the downstream of the pipe was
> closed, when it checks for write errors.
> 
> Let me test it.

The test case is protected by a TTY prerequisite; that is not satisfied
on Windows, and the test is skipped. No harm done so far.

But when I run `test-tool pager` manually and quit out of the pager, the
tool does spin in the endless loop. The following fixup helps.


diff --git a/t/helper/test-pager.c b/t/helper/test-pager.c
index feb68b8643..5f1982411f 100644
--- a/t/helper/test-pager.c
+++ b/t/helper/test-pager.c
@@ -7,6 +7,8 @@ int cmd__pager(int argc, const char **argv)
 		usage("\ttest-tool pager");
 
 	setup_pager();
-	for (;;)
-		puts("y");
+	while (write_in_full(1, "y\n", 2) > 0)
+		;
+
+	return 0;
 }
-- 
2.30.0.119.g680bcb97f5