From: Johannes Schindelin <johannes.schindelin@xxxxxx> Since a9b8a09c3c30 (mingw: replace isatty() hack, 2016-12-22), we handle isatty() by special-casing the stdin/stdout/stderr file descriptors, caching the return value. However, we missed the case where dup2() overrides the respective file descriptor. That poses a problem e.g. where the `show` builtin asks for a pager very early, the `setup_pager()` function sets the pager depending on the return value of `isatty()` and then redirects stdout. Subsequently, `cmd_log_init_finish()` calls `setup_pager()` *again*. What should happen now is that `isatty()` reports that stdout is *not* a TTY and consequently stdout should be left alone. Let's override dup2() to handle this appropriately. This fixes https://github.com/git-for-windows/git/issues/1077 Signed-off-by: Johannes Schindelin <johannes.schindelin@xxxxxx> --- compat/mingw.h | 3 +++ compat/winansi.c | 12 ++++++++++++ 2 files changed, 15 insertions(+) diff --git a/compat/mingw.h b/compat/mingw.h index f31dcff2b..b04556ce0 100644 --- a/compat/mingw.h +++ b/compat/mingw.h @@ -390,6 +390,9 @@ int mingw_raise(int sig); int winansi_isatty(int fd); #define isatty winansi_isatty +int winansi_dup2(int oldfd, int newfd); +#define dup2 winansi_dup2 + void winansi_init(void); HANDLE winansi_get_osfhandle(int fd); diff --git a/compat/winansi.c b/compat/winansi.c index a11a0f16d..f4f08237f 100644 --- a/compat/winansi.c +++ b/compat/winansi.c @@ -474,6 +474,18 @@ static void die_lasterr(const char *fmt, ...) va_end(params); } +#undef dup2 +int winansi_dup2(int oldfd, int newfd) +{ + int ret = dup2(oldfd, newfd); + + if (!ret && newfd >= 0 && newfd <= 2) + fd_is_interactive[newfd] = oldfd < 0 || oldfd > 2 ? + 0 : fd_is_interactive[oldfd]; + + return ret; +} + static HANDLE duplicate_handle(HANDLE hnd) { HANDLE hresult, hproc = GetCurrentProcess(); -- gitgitgadget
