Initial pass at signal propogation. Only SIGINT is passed along at this point.

4 files changed, 144 insertions, 18 deletions

diff --git a/qarsh/qarsh.c b/qarsh/qarsh.c
index 0b91f5d..2c709c7 100644
--- a/qarsh/qarsh.c
+++ b/qarsh/qarsh.c
@@ -5,6 +5,7 @@
  *
  */
 
+#define _GNU_SOURCE
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
@@ -28,6 +29,7 @@
 
 /* Globals */
 int qarsh_fd = -1;		/* The control connection to qarshd */
+int signal_to_send = 0;
 
 void
 usage()
@@ -60,6 +62,12 @@ copyargs(char **argv)
 }
 
 void
+sig_handler(int sig)
+{
+	signal_to_send = sig;
+}
+
+void
 set_remote_user(char *user, char *group)
 {
 	struct qa_packet *qp;
@@ -90,6 +98,8 @@ run_remote_cmd(char *cmdline)
 	int l_in, l_out, l_err;  /* listening sockets */
 	int c_in, c_out, c_err;  /* client sockets */
 	fd_set readfds, testfds;
+        sigset_t sigmask, orig_sigmask;
+	struct sigaction sa;
 	int nset;
 	struct sockaddr_in caddr;
 	socklen_t clen;
@@ -160,9 +170,19 @@ run_remote_cmd(char *cmdline)
 	FD_SET(c_out, &readfds);
 	FD_SET(c_err, &readfds);
 	FD_SET(fileno(stdin), &readfds);
+	/* Setup signal handling stuff so we can propogate signals */
+	sigemptyset(&sigmask);
+	sigaddset(&sigmask, SIGINT);
+	sigprocmask(SIG_BLOCK, &sigmask, &orig_sigmask);
+	sa.sa_handler = sig_handler;
+	sa.sa_mask = sigmask;
+	sa.sa_flags = SA_RESTART;
+	sigaction(SIGINT, &sa, NULL);
 
 	if (fcntl(fileno(stdin), F_SETFL, O_NONBLOCK) != 0) {
-		fprintf(stderr, "fcntl stdin O_NONBLOCK failed, %d: %s\n", errno, strerror(errno));
+		fprintf(stderr, 
+			"fcntl stdin O_NONBLOCK failed, %d: %s\n", 
+			errno, strerror(errno));
 	}
 	buf = malloc(1024);
 	memset(buf, 0, 1024);
@@ -171,47 +191,65 @@ run_remote_cmd(char *cmdline)
 		testfds = readfds;
 		memset(buf, 0, 1024);
 
-		nset = select(FD_SETSIZE, &testfds, NULL, NULL, NULL);
-		if (FD_ISSET(fileno(stdin), &testfds)) {
+		nset = pselect(FD_SETSIZE, &testfds, NULL, NULL, NULL, 
+				&orig_sigmask);
+		if (nset == -1 && errno == EINTR) {
+			nset = 0;
+		}
+			
+		if (signal_to_send) {
+			qp = make_qp_kill(signal_to_send);
+			send_packet(qarsh_fd, qp);
+			qpfree(qp);
+			signal_to_send = 0;
+		}
+		if (nset && FD_ISSET(fileno(stdin), &testfds)) {
 			do {
 				bufsize = read(fileno(stdin), buf, 1024);
-				write(c_in, buf, bufsize);
+				if (bufsize > 0) 
+					write(c_in, buf, bufsize);
 			} while (bufsize == 1024);
 			if (bufsize == 0) {
 				FD_CLR(fileno(stdin), &readfds);
 				close(c_in);
 				c_in = 0;
 			}
+			nset--;
 		}
-		if (c_out && FD_ISSET(c_out, &testfds)) {
+		if (nset && c_out && FD_ISSET(c_out, &testfds)) {
 			do {	
 				bufsize = read(c_out, buf, 1024);
-				write(fileno(stdout), buf, bufsize);
+				if (bufsize > 0) 
+					write(fileno(stdout), buf, bufsize);
 			} while (bufsize == 1024);
 			if (bufsize == 0) {
 				FD_CLR(c_out, &readfds);
 				close(c_out);
 				c_out = 0;
 			}
+			nset--;
 		}
-		if (c_err && FD_ISSET(c_err, &testfds)) {
+		if (nset && c_err && FD_ISSET(c_err, &testfds)) {
 			do {	
 				bufsize = read(c_err, buf, 1024);
-				write(fileno(stderr), buf, bufsize);
+				if (bufsize > 0) 
+					write(fileno(stderr), buf, bufsize);
 			} while (bufsize == 1024);
 			if (bufsize == 0) {
 				FD_CLR(c_err, &readfds);
 				close(c_err);
 				c_err = 0;
 			}
+			nset--;
 		}
-		if (FD_ISSET(qarsh_fd, &testfds)) {
+		if (nset && FD_ISSET(qarsh_fd, &testfds)) {
 			qp = recv_packet(qarsh_fd);
 		
 			/* dump_qp(qp); */
 			if (qp && qp->qp_type == QP_CMDEXIT) {
 				break;
 			}
+			nset--;
 		}
 
 	}
diff --git a/qarsh/qarsh_packet.c b/qarsh/qarsh_packet.c
index cc4f082..bad614f 100644
--- a/qarsh/qarsh_packet.c
+++ b/qarsh/qarsh_packet.c
@@ -17,6 +17,7 @@ int parse_qp_ack(xmlXPathContextPtr ctxt, struct qa_packet *qp);
 int parse_qp_runcmd(xmlXPathContextPtr ctxt, struct qa_packet *qp);
 int parse_qp_cmdexit(xmlXPathContextPtr ctxt, struct qa_packet *qp);
 int parse_qp_setuser(xmlXPathContextPtr ctxt, struct qa_packet *qp);
+int parse_qp_kill(xmlXPathContextPtr ctxt, struct qa_packet *qp);
 
 void string_qp_hello(xmlNodePtr node, struct qa_packet *qp);
 void string_qp_returncode(xmlNodePtr node, struct qa_packet *qp);
@@ -24,6 +25,7 @@ void string_qp_runcmd(xmlNodePtr node, struct qa_packet *qp);
 void string_qp_ack(xmlNodePtr node, struct qa_packet *qp);
 void string_qp_cmdexit(xmlNodePtr node, struct qa_packet *qp);
 void string_qp_setuser(xmlNodePtr node, struct qa_packet *qp);
+void string_qp_kill(xmlNodePtr node, struct qa_packet *qp);
 
 void free_qp_hello(struct qa_packet *qp);
 void free_qp_returncode(struct qa_packet *qp);
@@ -35,6 +37,7 @@ void dump_qp_runcmd(struct qa_packet *qp);
 void dump_qp_returncode(struct qa_packet *qp);
 void dump_qp_cmdexit(struct qa_packet *qp);
 void dump_qp_setuser(struct qa_packet *qp);
+void dump_qp_kill(struct qa_packet *qp);
 
 
 struct packet_internals {
@@ -86,6 +89,12 @@ struct packet_internals {
 		.pi_string = string_qp_setuser,
 		.pi_free = free_qp_setuser,
 		.pi_dump = dump_qp_setuser
+	}, {
+		.pi_name = "kill",
+		.pi_parse = parse_qp_kill,
+		.pi_string = string_qp_kill,
+		.pi_free = NULL,
+		.pi_dump = dump_qp_kill
 	}
 };
 	
@@ -196,6 +205,17 @@ parse_qp_setuser(xmlXPathContextPtr ctxt, struct qa_packet *qp)
 	return 0;
 }
 	
+int
+parse_qp_kill(xmlXPathContextPtr ctxt, struct qa_packet *qp)
+{
+	char *s;
+
+	s = get_xpath_string(ctxt, "param[@name='signal']");
+	qp->qp_kill.qp_sig = atoi(s);
+	free(s);
+	return 0;
+}
+
 struct qa_packet *
 parse_packet(xmlXPathContextPtr ctxt)
 {
@@ -349,6 +369,14 @@ void string_qp_setuser(xmlNodePtr node, struct qa_packet *qp)
 	}
 }
 
+void string_qp_kill(xmlNodePtr node, struct qa_packet *qp)
+{
+	char tmpstr[32];
+
+	snprintf(tmpstr, 32, "%d", qp->qp_kill.qp_sig);
+	xmlAddChild(node, make_param("signal", tmpstr));
+}
+
 /* Must pass in a pointer, but not a malloc'ed pointer */
 char *
 qptostr(struct qa_packet *qp, char **qpstr, int *qpsize)
@@ -476,6 +504,20 @@ make_qp_setuser(char *user, char *group)
 	return qp;
 }
 
+struct qa_packet *
+make_qp_kill(int sig)
+{
+	struct qa_packet *qp;
+	qp = malloc(sizeof *qp);
+	assert(qp);
+	memset(qp, 0, sizeof *qp);
+	
+	qp->qp_type = QP_KILL;
+	qp->qp_kill.qp_sig = sig;
+
+	return qp;
+}
+
 /*
  * Packet deallocation functions
  */
@@ -560,6 +602,12 @@ dump_qp_setuser(struct qa_packet *qp)
 }
 
 void
+dump_qp_kill(struct qa_packet *qp)
+{
+	printf("\tsig: %d\n", qp->qp_kill.qp_sig);
+}
+
+void
 dump_qp(struct qa_packet *qp)
 {
 	printf("%s #%d\n", QP_NAME(qp->qp_type), qp->qp_seq);
diff --git a/qarsh/qarsh_packet.h b/qarsh/qarsh_packet.h
index b6d821b..64b2b2a 100644
--- a/qarsh/qarsh_packet.h
+++ b/qarsh/qarsh_packet.h
@@ -12,7 +12,8 @@ enum qa_packet_type {
 	QP_RUNCMD = 3,
 	QP_ACK = 4,
 	QP_CMDEXIT = 5,
-	QP_SETUSER = 6
+	QP_SETUSER = 6,
+	QP_KILL = 7
 };
 
 struct qp_hello_pkt {
@@ -48,6 +49,10 @@ struct qp_setuser_pkt {
 	char *qp_group;
 };
 
+struct qp_kill_pkt {
+	int qp_sig;
+};
+
 #define QP_VERSION 1
 
 struct qa_packet {
@@ -60,6 +65,7 @@ struct qa_packet {
 		struct qp_ack_pkt ack;
 		struct qp_cmdexit_pkt cmdexit;
 		struct qp_setuser_pkt setuser;
+		struct qp_kill_pkt kill;
 	} qp_u;
 };
 
@@ -69,6 +75,7 @@ struct qa_packet {
 #define qp_ack qp_u.ack
 #define qp_cmdexit qp_u.cmdexit
 #define qp_setuser qp_u.setuser
+#define qp_kill qp_u.kill
 
 /* Prototypes */
 char *qp_packet_type(enum qa_packet_type t);
@@ -79,6 +86,7 @@ struct qa_packet *make_qp_ack(enum qa_packet_type t, int i);
 struct qa_packet *make_qp_runcmd(char *cmdline, int p_in, int p_out, int p_err);
 struct qa_packet *make_qp_cmdexit(pid_t pid, int status);
 struct qa_packet *make_qp_setuser(char *user, char *group);
+struct qa_packet *make_qp_kill(int sig);
 char *qptostr(struct qa_packet *qp, char **qpstr, int *qpsize);
 void qpfree(struct qa_packet *qp);
 void dump_qp(struct qa_packet *qp);
diff --git a/qarsh/qarshd.c b/qarsh/qarshd.c
index d443704..bf8353b 100644
--- a/qarsh/qarshd.c
+++ b/qarsh/qarshd.c
@@ -1,4 +1,5 @@
 
+#define _GNU_SOURCE
 #include <stdio.h>
 #include <errno.h>
 #include <unistd.h>
@@ -25,6 +26,7 @@
 
 /* Globals */
 struct sockaddr_in peername;
+int child_exitted = 0;
 
 int
 setup_user(char *user, char *group)
@@ -49,6 +51,12 @@ setup_user(char *user, char *group)
 	return 1;
 }
 
+void
+sig_handler(int sig)
+{
+	if (sig == SIGCHLD) child_exitted++;
+}
+
 pid_t 
 run_cmd(const char *cmd, int p_in, int p_out, int p_err)
 {
@@ -113,20 +121,40 @@ handle_packets(int infd)
 {
 	fd_set rfds;
 	int nfd;
-	struct timeval timeout;
+	struct timespec timeout;
 	struct qa_packet *qp = NULL, *rp = NULL;
+        sigset_t sigmask, orig_sigmask;
+	struct sigaction sa;
 
 	pid_t child_pid = 0;
 	int child_status;
 
+	sigemptyset(&sigmask);
+	sigaddset(&sigmask, SIGCHLD);
+	sigprocmask(SIG_BLOCK, &sigmask, &orig_sigmask);
+	sa.sa_handler = sig_handler;
+	sa.sa_mask = sigmask;
+	sa.sa_flags = SA_RESTART;
+	sigaction(SIGCHLD, &sa, NULL);
+
 	for (;;) {
 		FD_SET(infd, &rfds);
 		timeout.tv_sec = 5;
-		timeout.tv_usec = 0;
 
-		nfd = select(infd+1, &rfds, NULL, NULL, &timeout);
+		nfd = pselect(infd+1, &rfds, NULL, NULL, &timeout, 
+				&orig_sigmask);
 		if (nfd < 0) {
-			syslog(LOG_ERR, "select errno %d, %s\n", errno, strerror(errno));
+			if (errno == EINTR) {
+				/* Handle signals here */
+				if (child_exitted) {
+					waitpid(child_pid, &child_status, 0);
+					rp = make_qp_cmdexit(child_pid, child_status);
+					send_packet(fileno(stdout), rp);
+					qpfree(rp);
+				}
+			} else {
+				syslog(LOG_ERR, "select errno %d, %s\n", errno, strerror(errno));
+			}
 		} else if (nfd > 0) {
 			qp = recv_packet(infd);
 			if (qp == NULL) {
@@ -134,6 +162,14 @@ handle_packets(int infd)
 				break;
 			}
 			switch (qp->qp_type) {
+			case QP_KILL:
+				if (child_pid) {
+
+					syslog(LOG_INFO, "Sending child %d signal %d", 
+						child_pid, qp->qp_kill.qp_sig);
+					kill(child_pid, qp->qp_kill.qp_sig);
+				}
+				break;
 			case QP_SETUSER:
 				if (setup_user(qp->qp_setuser.qp_user,
 						qp->qp_setuser.qp_group) == 0) {
@@ -149,10 +185,6 @@ handle_packets(int infd)
 						qp->qp_runcmd.qp_stdin_port,
 						qp->qp_runcmd.qp_stdout_port,
 						qp->qp_runcmd.qp_stderr_port);
-				waitpid(child_pid, &child_status, 0);
-				rp = make_qp_cmdexit(child_pid, child_status);
-				send_packet(fileno(stdout), rp);
-				qpfree(rp);
 				break;
 			default:
 				syslog(LOG_WARNING,