trace-cmd: Make listen connection run as a separate process

Fork off children when a process is connected, and run continuously.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 60 insertions, 29 deletions

diff --git a/trace-listen.c b/trace-listen.c
index 419cbd1..9d375af 100644
--- a/trace-listen.c
+++ b/trace-listen.c
@@ -27,6 +27,7 @@
 #include <getopt.h>
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/wait.h>
 #include <netdb.h>
 #include <unistd.h>
 #include <fcntl.h>
@@ -367,6 +368,63 @@ static void process_client(const char *node, const char *port, int fd)
         }
 }
 
+static void do_connection(int cfd, struct sockaddr_storage *peer_addr,
+                          socklen_t peer_addr_len)
+{
+        char host[NI_MAXHOST], service[NI_MAXSERV];
+        char buf[BUFSIZ];
+        ssize_t nread;
+        pid_t pid;
+        int s;
+        int status;
+        int ret;
+
+        /* Clean up any children that has started before */
+        do {
+                ret = waitpid(0, &status, WNOHANG);
+        } while (ret > 0);
+
+        pid = fork();
+        if (pid < 0) {
+                warning("failed to create child");
+                return;
+        }
+
+        if (pid > 0) {
+                close(cfd);
+                return;
+        }
+
+        s = getnameinfo((struct sockaddr *)peer_addr, peer_addr_len,
+                        host, NI_MAXHOST,
+                        service, NI_MAXSERV, NI_NUMERICSERV);
+
+        if (s == 0)
+                printf("Connected with %s:%s\n",
+                       host, service);
+        else {
+                printf("Error with getnameinfo: %s\n",
+                       gai_strerror(s));
+                close(cfd);
+                return;
+        }
+
+        process_client(host, service, cfd);
+
+        do {
+                if (nread > 0)
+                        nread = read(cfd, buf, BUFSIZ);
+                if (cfd < 0)
+                        die("client");
+                if (nread > 0)
+                        write(1, buf, nread);
+        } while (nread);
+
+        close(cfd);
+
+        exit(0);
+}
+
 static void do_listen(char *port)
 {
         struct addrinfo hints;
@@ -374,9 +432,6 @@ static void do_listen(char *port)
         int sfd, s, cfd;
         struct sockaddr_storage peer_addr;
         socklen_t peer_addr_len;
-        ssize_t nread;
-        char buf[BUFSIZ];
-        char host[NI_MAXHOST], service[NI_MAXSERV];
 
         memset(&hints, 0, sizeof(hints));
         hints.ai_family = AF_UNSPEC;
@@ -413,34 +468,10 @@ static void do_listen(char *port)
                 cfd = accept(sfd, (struct sockaddr *)&peer_addr, &peer_addr_len);
                 if (cfd < 0)
                         die("connecting");
-                s = getnameinfo((struct sockaddr *)&peer_addr, peer_addr_len,
-                                host, NI_MAXHOST,
-                                service, NI_MAXSERV, NI_NUMERICSERV);
-
-                if (s == 0)
-                        printf("Connected with %s:%s\n",
-                               host, service);
-                else {
-                        printf("Error with getnameinfo: %s\n",
-                               gai_strerror(s));
-                        close(cfd);
-                        close(sfd);
-                        return;
-                }
-
-                process_client(host, service, cfd);
 
-                do {
-                        if (nread > 0)
-                                nread = read(cfd, buf, BUFSIZ);
-                        if (cfd < 0)
-                                die("client");
-                        if (nread > 0)
-                                write(1, buf, nread);
-                } while (nread);
+                do_connection(cfd, &peer_addr, peer_addr_len);
 
-                close(cfd);
-        } while (0);
+        } while (1);
 }
 
 static void start_daemon(void)