--- a/contrib/chg/chg.c	Wed Oct 07 16:02:45 2015 -0700
+++ b/contrib/chg/chg.c	Mon Jan 02 14:02:47 2017 +0000
@@ -303,214 +303,7 @@
 	}
 }
 
-static pid_t pagerpid = 0;
-static pid_t peerpgid = 0;
-static pid_t peerpid = 0;
-
-static void forwardsignal(int sig)
-{
-	assert(peerpid > 0);
-	if (kill(peerpid, sig) < 0)
-		abortmsgerrno("cannot kill %d", peerpid);
-	debugmsg("forward signal %d", sig);
-}
-
-static void forwardsignaltogroup(int sig)
-{
-	/* prefer kill(-pgid, sig), fallback to pid if pgid is invalid */
-	pid_t killpid = peerpgid > 1 ? -peerpgid : peerpid;
-	if (kill(killpid, sig) < 0)
-		abortmsgerrno("cannot kill %d", killpid);
-	debugmsg("forward signal %d to %d", sig, killpid);
-}
-
-static void handlestopsignal(int sig)
-{
-	sigset_t unblockset, oldset;
-	struct sigaction sa, oldsa;
-	if (sigemptyset(&unblockset) < 0)
-		goto error;
-	if (sigaddset(&unblockset, sig) < 0)
-		goto error;
-	memset(&sa, 0, sizeof(sa));
-	sa.sa_handler = SIG_DFL;
-	sa.sa_flags = SA_RESTART;
-	if (sigemptyset(&sa.sa_mask) < 0)
-		goto error;
-
-	forwardsignal(sig);
-	if (raise(sig) < 0)  /* resend to self */
-		goto error;
-	if (sigaction(sig, &sa, &oldsa) < 0)
-		goto error;
-	if (sigprocmask(SIG_UNBLOCK, &unblockset, &oldset) < 0)
-		goto error;
-	/* resent signal will be handled before sigprocmask() returns */
-	if (sigprocmask(SIG_SETMASK, &oldset, NULL) < 0)
-		goto error;
-	if (sigaction(sig, &oldsa, NULL) < 0)
-		goto error;
-	return;
-
-error:
-	abortmsgerrno("failed to handle stop signal");
-}
-
-static void handlechildsignal(int sig UNUSED_)
-{
-	if (peerpid == 0 || pagerpid == 0)
-		return;
-	/* if pager exits, notify the server with SIGPIPE immediately.
-	 * otherwise the server won't get SIGPIPE if it does not write
-	 * anything. (issue5278) */
-	if (waitpid(pagerpid, NULL, WNOHANG) == pagerpid)
-		kill(peerpid, SIGPIPE);
-}
-
-static void setupsignalhandler(const hgclient_t *hgc)
-{
-	pid_t pid = hgc_peerpid(hgc);
-	if (pid <= 0)
-		return;
-	peerpid = pid;
-
-	pid_t pgid = hgc_peerpgid(hgc);
-	peerpgid = (pgid <= 1 ? 0 : pgid);
-
-	struct sigaction sa;
-	memset(&sa, 0, sizeof(sa));
-	sa.sa_handler = forwardsignaltogroup;
-	sa.sa_flags = SA_RESTART;
-	if (sigemptyset(&sa.sa_mask) < 0)
-		goto error;
-
-	if (sigaction(SIGHUP, &sa, NULL) < 0)
-		goto error;
-	if (sigaction(SIGINT, &sa, NULL) < 0)
-		goto error;
-
-	/* terminate frontend by double SIGTERM in case of server freeze */
-	sa.sa_handler = forwardsignal;
-	sa.sa_flags |= SA_RESETHAND;
-	if (sigaction(SIGTERM, &sa, NULL) < 0)
-		goto error;
-
-	/* notify the worker about window resize events */
-	sa.sa_flags = SA_RESTART;
-	if (sigaction(SIGWINCH, &sa, NULL) < 0)
-		goto error;
-	/* propagate job control requests to worker */
-	sa.sa_handler = forwardsignal;
-	sa.sa_flags = SA_RESTART;
-	if (sigaction(SIGCONT, &sa, NULL) < 0)
-		goto error;
-	sa.sa_handler = handlestopsignal;
-	sa.sa_flags = SA_RESTART;
-	if (sigaction(SIGTSTP, &sa, NULL) < 0)
-		goto error;
-	/* get notified when pager exits */
-	sa.sa_handler = handlechildsignal;
-	sa.sa_flags = SA_RESTART;
-	if (sigaction(SIGCHLD, &sa, NULL) < 0)
-		goto error;
-
-	return;
-
-error:
-	abortmsgerrno("failed to set up signal handlers");
-}
-
-static void restoresignalhandler()
-{
-	struct sigaction sa;
-	memset(&sa, 0, sizeof(sa));
-	sa.sa_handler = SIG_DFL;
-	sa.sa_flags = SA_RESTART;
-	if (sigemptyset(&sa.sa_mask) < 0)
-		goto error;
-
-	if (sigaction(SIGHUP, &sa, NULL) < 0)
-		goto error;
-	if (sigaction(SIGTERM, &sa, NULL) < 0)
-		goto error;
-	if (sigaction(SIGWINCH, &sa, NULL) < 0)
-		goto error;
-	if (sigaction(SIGCONT, &sa, NULL) < 0)
-		goto error;
-	if (sigaction(SIGTSTP, &sa, NULL) < 0)
-		goto error;
-	if (sigaction(SIGCHLD, &sa, NULL) < 0)
-		goto error;
-
-	/* ignore Ctrl+C while shutting down to make pager exits cleanly */
-	sa.sa_handler = SIG_IGN;
-	if (sigaction(SIGINT, &sa, NULL) < 0)
-		goto error;
-
-	peerpid = 0;
-	return;
-
-error:
-	abortmsgerrno("failed to restore signal handlers");
-}
-
-/* This implementation is based on hgext/pager.py (post 369741ef7253)
- * Return 0 if pager is not started, or pid of the pager */
-static pid_t setuppager(hgclient_t *hgc, const char *const args[],
-		       size_t argsize)
-{
-	const char *pagercmd = hgc_getpager(hgc, args, argsize);
-	if (!pagercmd)
-		return 0;
-
-	int pipefds[2];
-	if (pipe(pipefds) < 0)
-		return 0;
-	pid_t pid = fork();
-	if (pid < 0)
-		goto error;
-	if (pid > 0) {
-		close(pipefds[0]);
-		if (dup2(pipefds[1], fileno(stdout)) < 0)
-			goto error;
-		if (isatty(fileno(stderr))) {
-			if (dup2(pipefds[1], fileno(stderr)) < 0)
-				goto error;
-		}
-		close(pipefds[1]);
-		hgc_attachio(hgc);  /* reattach to pager */
-		return pid;
-	} else {
-		dup2(pipefds[0], fileno(stdin));
-		close(pipefds[0]);
-		close(pipefds[1]);
-
-		int r = execlp("/bin/sh", "/bin/sh", "-c", pagercmd, NULL);
-		if (r < 0) {
-			abortmsgerrno("cannot start pager '%s'", pagercmd);
-		}
-		return 0;
-	}
-
-error:
-	close(pipefds[0]);
-	close(pipefds[1]);
-	abortmsgerrno("failed to prepare pager");
-	return 0;
-}
-
-static void waitpager(pid_t pid)
-{
-	/* close output streams to notify the pager its input ends */
-	fclose(stdout);
-	fclose(stderr);
-	while (1) {
-		pid_t ret = waitpid(pid, NULL, 0);
-		if (ret == -1 && errno == EINTR)
-			continue;
-		break;
-	}
-}
+#include "procutil.c"
 
 /* Run instructions sent from the server like unlink and set redirect path
  * Return 1 if reconnect is needed, otherwise 0 */

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/contrib/chg/procutil.c	Mon Jan 02 14:02:47 2017 +0000
@@ -0,0 +1,217 @@
+/*
+ * Utilities about process handling - signal and subprocess (ex. pager)
+ *
+ * Copyright (c) 2011 Yuya Nishihara <yuya@tcha.org>
+ *
+ * This software may be used and distributed according to the terms of the
+ * GNU General Public License version 2 or any later version.
+ */
+
+static pid_t pagerpid = 0;
+static pid_t peerpgid = 0;
+static pid_t peerpid = 0;
+
+static void forwardsignal(int sig)
+{
+	assert(peerpid > 0);
+	if (kill(peerpid, sig) < 0)
+		abortmsgerrno("cannot kill %d", peerpid);
+	debugmsg("forward signal %d", sig);
+}
+
+static void forwardsignaltogroup(int sig)
+{
+	/* prefer kill(-pgid, sig), fallback to pid if pgid is invalid */
+	pid_t killpid = peerpgid > 1 ? -peerpgid : peerpid;
+	if (kill(killpid, sig) < 0)
+		abortmsgerrno("cannot kill %d", killpid);
+	debugmsg("forward signal %d to %d", sig, killpid);
+}
+
+static void handlestopsignal(int sig)
+{
+	sigset_t unblockset, oldset;
+	struct sigaction sa, oldsa;
+	if (sigemptyset(&unblockset) < 0)
+		goto error;
+	if (sigaddset(&unblockset, sig) < 0)
+		goto error;
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = SIG_DFL;
+	sa.sa_flags = SA_RESTART;
+	if (sigemptyset(&sa.sa_mask) < 0)
+		goto error;
+
+	forwardsignal(sig);
+	if (raise(sig) < 0)  /* resend to self */
+		goto error;
+	if (sigaction(sig, &sa, &oldsa) < 0)
+		goto error;
+	if (sigprocmask(SIG_UNBLOCK, &unblockset, &oldset) < 0)
+		goto error;
+	/* resent signal will be handled before sigprocmask() returns */
+	if (sigprocmask(SIG_SETMASK, &oldset, NULL) < 0)
+		goto error;
+	if (sigaction(sig, &oldsa, NULL) < 0)
+		goto error;
+	return;
+
+error:
+	abortmsgerrno("failed to handle stop signal");
+}
+
+static void handlechildsignal(int sig UNUSED_)
+{
+	if (peerpid == 0 || pagerpid == 0)
+		return;
+	/* if pager exits, notify the server with SIGPIPE immediately.
+	 * otherwise the server won't get SIGPIPE if it does not write
+	 * anything. (issue5278) */
+	if (waitpid(pagerpid, NULL, WNOHANG) == pagerpid)
+		kill(peerpid, SIGPIPE);
+}
+
+static void setupsignalhandler(const hgclient_t *hgc)
+{
+	pid_t pid = hgc_peerpid(hgc);
+	if (pid <= 0)
+		return;
+	peerpid = pid;
+
+	pid_t pgid = hgc_peerpgid(hgc);
+	peerpgid = (pgid <= 1 ? 0 : pgid);
+
+	struct sigaction sa;
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = forwardsignaltogroup;
+	sa.sa_flags = SA_RESTART;
+	if (sigemptyset(&sa.sa_mask) < 0)
+		goto error;
+
+	if (sigaction(SIGHUP, &sa, NULL) < 0)
+		goto error;
+	if (sigaction(SIGINT, &sa, NULL) < 0)
+		goto error;
+
+	/* terminate frontend by double SIGTERM in case of server freeze */
+	sa.sa_handler = forwardsignal;
+	sa.sa_flags |= SA_RESETHAND;
+	if (sigaction(SIGTERM, &sa, NULL) < 0)
+		goto error;
+
+	/* notify the worker about window resize events */
+	sa.sa_flags = SA_RESTART;
+	if (sigaction(SIGWINCH, &sa, NULL) < 0)
+		goto error;
+	/* propagate job control requests to worker */
+	sa.sa_handler = forwardsignal;
+	sa.sa_flags = SA_RESTART;
+	if (sigaction(SIGCONT, &sa, NULL) < 0)
+		goto error;
+	sa.sa_handler = handlestopsignal;
+	sa.sa_flags = SA_RESTART;
+	if (sigaction(SIGTSTP, &sa, NULL) < 0)
+		goto error;
+	/* get notified when pager exits */
+	sa.sa_handler = handlechildsignal;
+	sa.sa_flags = SA_RESTART;
+	if (sigaction(SIGCHLD, &sa, NULL) < 0)
+		goto error;
+
+	return;
+
+error:
+	abortmsgerrno("failed to set up signal handlers");
+}
+
+static void restoresignalhandler()
+{
+	struct sigaction sa;
+	memset(&sa, 0, sizeof(sa));
+	sa.sa_handler = SIG_DFL;
+	sa.sa_flags = SA_RESTART;
+	if (sigemptyset(&sa.sa_mask) < 0)
+		goto error;
+
+	if (sigaction(SIGHUP, &sa, NULL) < 0)
+		goto error;
+	if (sigaction(SIGTERM, &sa, NULL) < 0)
+		goto error;
+	if (sigaction(SIGWINCH, &sa, NULL) < 0)
+		goto error;
+	if (sigaction(SIGCONT, &sa, NULL) < 0)
+		goto error;
+	if (sigaction(SIGTSTP, &sa, NULL) < 0)
+		goto error;
+	if (sigaction(SIGCHLD, &sa, NULL) < 0)
+		goto error;
+
+	/* ignore Ctrl+C while shutting down to make pager exits cleanly */
+	sa.sa_handler = SIG_IGN;
+	if (sigaction(SIGINT, &sa, NULL) < 0)
+		goto error;
+
+	peerpid = 0;
+	return;
+
+error:
+	abortmsgerrno("failed to restore signal handlers");
+}
+
+/* This implementation is based on hgext/pager.py (post 369741ef7253)
+ * Return 0 if pager is not started, or pid of the pager */
+static pid_t setuppager(hgclient_t *hgc, const char *const args[],
+		       size_t argsize)
+{
+	const char *pagercmd = hgc_getpager(hgc, args, argsize);
+	if (!pagercmd)
+		return 0;
+
+	int pipefds[2];
+	if (pipe(pipefds) < 0)
+		return 0;
+	pid_t pid = fork();
+	if (pid < 0)
+		goto error;
+	if (pid > 0) {
+		close(pipefds[0]);
+		if (dup2(pipefds[1], fileno(stdout)) < 0)
+			goto error;
+		if (isatty(fileno(stderr))) {
+			if (dup2(pipefds[1], fileno(stderr)) < 0)
+				goto error;
+		}
+		close(pipefds[1]);
+		hgc_attachio(hgc);  /* reattach to pager */
+		return pid;
+	} else {
+		dup2(pipefds[0], fileno(stdin));
+		close(pipefds[0]);
+		close(pipefds[1]);
+
+		int r = execlp("/bin/sh", "/bin/sh", "-c", pagercmd, NULL);
+		if (r < 0) {
+			abortmsgerrno("cannot start pager '%s'", pagercmd);
+		}
+		return 0;
+	}
+
+error:
+	close(pipefds[0]);
+	close(pipefds[1]);
+	abortmsgerrno("failed to prepare pager");
+	return 0;
+}
+
+static void waitpager(pid_t pid)
+{
+	/* close output streams to notify the pager its input ends */
+	fclose(stdout);
+	fclose(stderr);
+	while (1) {
+		pid_t ret = waitpid(pid, NULL, 0);
+		if (ret == -1 && errno == EINTR)
+			continue;
+		break;
+	}
+}