@@ -1,4 +1,4 @@
-#include "git-compat-util.h"
+#include "cache.h"
#include "compat/terminal.h"
#include "sigchain.h"
#include "strbuf.h"
@@ -24,6 +24,102 @@ static volatile sig_atomic_t term_fd_needs_closing;
static int term_fd = -1;
static struct termios old_term;
+static const char *background_resume_msg;
+static const char *restore_error_msg;
+static volatile sig_atomic_t ttou_received;
+
+/* async safe error function for use by signal handlers. */
+static void write_err(const char *msg)
+{
+ write_in_full(2, "error: ", strlen("error: "));
+ write_in_full(2, msg, strlen(msg));
+ write_in_full(2, "\n", 1);
+}
+
+static void print_background_resume_msg(int signo)
+{
+ int saved_errno = errno;
+ sigset_t mask;
+ struct sigaction old_sa;
+ struct sigaction sa = { .sa_handler = SIG_DFL };
+
+ ttou_received = 1;
+ write_err(background_resume_msg);
+ sigaction(signo, &sa, &old_sa);
+ raise(signo);
+ sigemptyset(&mask);
+ sigaddset(&mask, signo);
+ sigprocmask(SIG_UNBLOCK, &mask, NULL);
+ /* Stopped here */
+ sigprocmask(SIG_BLOCK, &mask, NULL);
+ sigaction(signo, &old_sa, NULL);
+ errno = saved_errno;
+}
+
+static void restore_terminal_on_suspend(int signo)
+{
+ int saved_errno = errno;
+ int res;
+ struct termios t;
+ sigset_t mask;
+ struct sigaction old_sa;
+ struct sigaction sa = { .sa_handler = SIG_DFL };
+ int can_restore = 1;
+
+ if (tcgetattr(term_fd, &t) < 0)
+ can_restore = 0;
+
+ if (tcsetattr(term_fd, TCSAFLUSH, &old_term) < 0)
+ write_err(restore_error_msg);
+
+ sigaction(signo, &sa, &old_sa);
+ raise(signo);
+ sigemptyset(&mask);
+ sigaddset(&mask, signo);
+ sigprocmask(SIG_UNBLOCK, &mask, NULL);
+ /* Stopped here */
+ sigprocmask(SIG_BLOCK, &mask, NULL);
+ sigaction(signo, &old_sa, NULL);
+ if (!can_restore) {
+ write_err(restore_error_msg);
+ goto out;
+ }
+ /*
+ * If we resume in the background then we receive SIGTTOU when calling
+ * tcsetattr() below. Set up a handler to print an error message in that
+ * case.
+ */
+ sigemptyset(&mask);
+ sigaddset(&mask, SIGTTOU);
+ sa.sa_mask = old_sa.sa_mask;
+ sa.sa_handler = print_background_resume_msg;
+ sa.sa_flags = SA_RESTART;
+ sigaction(SIGTTOU, &sa, &old_sa);
+ again:
+ ttou_received = 0;
+ sigprocmask(SIG_UNBLOCK, &mask, NULL);
+ res = tcsetattr(term_fd, TCSAFLUSH, &t);
+ sigprocmask(SIG_BLOCK, &mask, NULL);
+ if (ttou_received)
+ goto again;
+ else if (res < 0)
+ write_err(restore_error_msg);
+ sigaction(SIGTTOU, &old_sa, NULL);
+ out:
+ errno = saved_errno;
+}
+
+static void reset_job_signals(void)
+{
+ if (restore_error_msg) {
+ signal(SIGTTIN, SIG_DFL);
+ signal(SIGTTOU, SIG_DFL);
+ signal(SIGTSTP, SIG_DFL);
+ restore_error_msg = NULL;
+ background_resume_msg = NULL;
+ }
+}
+
static void close_term_fd(void)
{
if (term_fd_needs_closing)
@@ -40,10 +136,13 @@ void restore_term(void)
tcsetattr(term_fd, TCSAFLUSH, &old_term);
close_term_fd();
sigchain_pop_common();
+ reset_job_signals();
}
int save_term(enum save_term_flags flags)
{
+ struct sigaction sa;
+
if (term_fd < 0)
term_fd = ((flags & SAVE_TERM_STDIN)
? 0
@@ -56,6 +155,26 @@ int save_term(enum save_term_flags flags)
return -1;
}
sigchain_push_common(restore_term_on_signal);
+ /*
+ * If job control is disabled then the shell will have set the
+ * disposition of SIGTSTP to SIG_IGN.
+ */
+ sigaction(SIGTSTP, NULL, &sa);
+ if (sa.sa_handler == SIG_IGN)
+ return 0;
+
+ /* avoid calling gettext() from signal handler */
+ background_resume_msg = _("cannot resume in the background, please use 'fg' to resume");
+ restore_error_msg = _("cannot restore terminal settings");
+ sa.sa_handler = restore_terminal_on_suspend;
+ sa.sa_flags = SA_RESTART;
+ sigemptyset(&sa.sa_mask);
+ sigaddset(&sa.sa_mask, SIGTSTP);
+ sigaddset(&sa.sa_mask, SIGTTIN);
+ sigaddset(&sa.sa_mask, SIGTTOU);
+ sigaction(SIGTSTP, &sa, NULL);
+ sigaction(SIGTTIN, &sa, NULL);
+ sigaction(SIGTTOU, &sa, NULL);
return 0;
}
@@ -78,6 +197,7 @@ static int disable_bits(enum save_term_flags flags, tcflag_t bits)
return 0;
sigchain_pop_common();
+ reset_job_signals();
close_term_fd();
return -1;
}
@@ -102,6 +222,7 @@ static int getchar_with_timeout(int timeout)
fd_set readfds;
int res;
+ again:
if (timeout >= 0) {
tv.tv_sec = timeout / 1000;
tv.tv_usec = (timeout % 1000) * 1000;
@@ -111,9 +232,14 @@ static int getchar_with_timeout(int timeout)
FD_ZERO(&readfds);
FD_SET(0, &readfds);
res = select(1, &readfds, NULL, NULL, tvp);
- if (res <= 0)
+ if (!res)
return EOF;
-
+ if (res < 0) {
+ if (errno == EINTR)
+ goto again;
+ else
+ return EOF;
+ }
return getchar();
}