[PATCH] Add a new extended SHA1 syntax <name>~<num>
[gitweb.git] / daemon.c
index 32196156bf9776af75c9adfcaacbef44cad13651..932d908bad3587b8ae7868112d587eaca775a303 100644 (file)
--- a/daemon.c
+++ b/daemon.c
@@ -3,8 +3,8 @@
 #include <signal.h>
 #include <sys/wait.h>
 #include <sys/socket.h>
+#include <netdb.h>
 #include <netinet/in.h>
-#include <arpa/inet.h>
 
 static const char daemon_usage[] = "git-daemon [--inetd | --port=n]";
 
@@ -26,6 +26,12 @@ static int upload(char *dir, int dirlen)
            access("HEAD", R_OK))
                return -1;
 
+       /*
+        * We'll ignore SIGTERM from now on, we have a
+        * good client.
+        */
+       signal(SIGTERM, SIG_IGN);
+
        /* git-upload-pack only ever reads stuff, so this is safe */
        execlp("git-upload-pack", "git-upload-pack", ".", NULL);
        return -1;
@@ -65,23 +71,23 @@ static int max_connections = 25;
 
 /* These are updated by the signal handler */
 static volatile unsigned int children_reaped = 0;
-pid_t dead_child[MAX_CHILDREN];
+static pid_t dead_child[MAX_CHILDREN];
 
 /* These are updated by the main loop */
 static unsigned int children_spawned = 0;
 static unsigned int children_deleted = 0;
 
-struct child {
+static struct child {
        pid_t pid;
-       int addrlen;
-       struct sockaddr_in address;
+       socklen_t addrlen;
+       struct sockaddr_storage address;
 } live_child[MAX_CHILDREN];
 
-static void add_child(int idx, pid_t pid, struct sockaddr_in *addr, int addrlen)
+static void add_child(int idx, pid_t pid, struct sockaddr *addr, socklen_t addrlen)
 {
        live_child[idx].pid = pid;
        live_child[idx].addrlen = addrlen;
-       live_child[idx].address = *addr;
+       memcpy(&live_child[idx].address, addr, addrlen);
 }
 
 /*
@@ -128,33 +134,24 @@ static void remove_child(pid_t pid, unsigned deleted, unsigned spawned)
  *
  * Really, this is just a place-holder for a _real_ algorithm.
  */
-static void kill_some_children(int connections, unsigned start, unsigned stop)
+static void kill_some_children(int signo, unsigned start, unsigned stop)
 {
        start %= MAX_CHILDREN;
        stop %= MAX_CHILDREN;
        while (start != stop) {
                if (!(start & 3))
-                       kill(live_child[start].pid, SIGTERM);
+                       kill(live_child[start].pid, signo);
                start = (start + 1) % MAX_CHILDREN;
        }
 }
 
-static void handle(int incoming, struct sockaddr_in *addr, int addrlen)
+static void check_max_connections(void)
 {
-       pid_t pid = fork();
-
-       if (pid) {
+       for (;;) {
                int active;
                unsigned spawned, reaped, deleted;
 
-               close(incoming);
-               if (pid < 0)
-                       return;
-
                spawned = children_spawned;
-               add_child(spawned % MAX_CHILDREN, pid, addr, addrlen);
-               children_spawned = ++spawned;
-
                reaped = children_reaped;
                deleted = children_deleted;
 
@@ -166,15 +163,36 @@ static void handle(int incoming, struct sockaddr_in *addr, int addrlen)
                children_deleted = deleted;
 
                active = spawned - deleted;
-               if (active > max_connections) {
-                       kill_some_children(active, deleted, spawned);
+               if (active <= max_connections)
+                       break;
 
-                       /* Wait to make sure they're gone */
-                       while (spawned - children_reaped > max_connections)
-                               sleep(1);
-               }
-                       
+               /* Kill some unstarted connections with SIGTERM */
+               kill_some_children(SIGTERM, deleted, spawned);
+               if (active <= max_connections << 1)
+                       break;
+
+               /* If the SIGTERM thing isn't helping use SIGKILL */
+               kill_some_children(SIGKILL, deleted, spawned);
+               sleep(1);
+       }
+}
+
+static void handle(int incoming, struct sockaddr *addr, socklen_t addrlen)
+{
+       pid_t pid = fork();
+
+       if (pid) {
+               unsigned idx;
+
+               close(incoming);
+               if (pid < 0)
+                       return;
 
+               idx = children_spawned % MAX_CHILDREN;
+               children_spawned++;
+               add_child(idx, pid, addr, addrlen);
+
+               check_max_connections();
                return;
        }
 
@@ -201,37 +219,109 @@ static void child_handler(int signo)
 
 static int serve(int port)
 {
-       int sockfd;
-       struct sockaddr_in addr;
+       struct addrinfo hints, *ai0, *ai;
+       int gai;
+       int socknum = 0, *socklist = NULL;
+       int maxfd = -1;
+       fd_set fds_init, fds;
+       char pbuf[NI_MAXSERV];
 
        signal(SIGCHLD, child_handler);
-       sockfd = socket(PF_INET, SOCK_STREAM, IPPROTO_IP);
-       if (sockfd < 0)
-               die("unable to open socket (%s)", strerror(errno));
-       memset(&addr, 0, sizeof(addr));
-       addr.sin_port = htons(port);
-       addr.sin_family = AF_INET;
-       if (bind(sockfd, (void *)&addr, sizeof(addr)) < 0)
-               die("unable to bind to port %d (%s)", port, strerror(errno));
-       if (listen(sockfd, 5) < 0)
-               die("unable to listen to port %d (%s)", port, strerror(errno));
+
+       sprintf(pbuf, "%d", port);
+       memset(&hints, 0, sizeof(hints));
+       hints.ai_family = AF_UNSPEC;
+       hints.ai_socktype = SOCK_STREAM;
+       hints.ai_protocol = IPPROTO_TCP;
+       hints.ai_flags = AI_PASSIVE;
+
+       gai = getaddrinfo(NULL, pbuf, &hints, &ai0);
+       if (gai)
+               die("getaddrinfo() failed: %s\n", gai_strerror(gai));
+
+       FD_ZERO(&fds_init);
+
+       for (ai = ai0; ai; ai = ai->ai_next) {
+               int sockfd;
+               int *newlist;
+
+               sockfd = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
+               if (sockfd < 0)
+                       continue;
+               if (sockfd >= FD_SETSIZE) {
+                       error("too large socket descriptor.");
+                       close(sockfd);
+                       continue;
+               }
+
+#ifdef IPV6_V6ONLY
+               if (ai->ai_family == AF_INET6) {
+                       int on = 1;
+                       setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY,
+                                  &on, sizeof(on));
+                       /* Note: error is not fatal */
+               }
+#endif
+
+               if (bind(sockfd, ai->ai_addr, ai->ai_addrlen) < 0) {
+                       close(sockfd);
+                       continue;       /* not fatal */
+               }
+               if (listen(sockfd, 5) < 0) {
+                       close(sockfd);
+                       continue;       /* not fatal */
+               }
+
+               newlist = realloc(socklist, sizeof(int) * (socknum + 1));
+               if (!newlist)
+                       die("memory allocation failed: %s", strerror(errno));
+
+               socklist = newlist;
+               socklist[socknum++] = sockfd;
+
+               FD_SET(sockfd, &fds_init);
+               if (maxfd < sockfd)
+                       maxfd = sockfd;
+       }
+
+       freeaddrinfo(ai0);
+
+       if (socknum == 0)
+               die("unable to allocate any listen sockets on port %u", port);
 
        for (;;) {
-               struct sockaddr_in in;
-               socklen_t addrlen = sizeof(in);
-               int incoming = accept(sockfd, (void *)&in, &addrlen);
-
-               if (incoming < 0) {
-                       switch (errno) {
-                       case EAGAIN:
-                       case EINTR:
-                       case ECONNABORTED:
-                               continue;
-                       default:
-                               die("accept returned %s", strerror(errno));
+               int i;
+               fds = fds_init;
+               
+               if (select(maxfd + 1, &fds, NULL, NULL, NULL) < 0) {
+                       if (errno != EINTR) {
+                               error("select failed, resuming: %s",
+                                     strerror(errno));
+                               sleep(1);
+                       }
+                       continue;
+               }
+
+               for (i = 0; i < socknum; i++) {
+                       int sockfd = socklist[i];
+
+                       if (FD_ISSET(sockfd, &fds)) {
+                               struct sockaddr_storage ss;
+                               socklen_t sslen = sizeof(ss);
+                               int incoming = accept(sockfd, (struct sockaddr *)&ss, &sslen);
+                               if (incoming < 0) {
+                                       switch (errno) {
+                                       case EAGAIN:
+                                       case EINTR:
+                                       case ECONNABORTED:
+                                               continue;
+                                       default:
+                                               die("accept returned %s", strerror(errno));
+                                       }
+                               }
+                               handle(incoming, (struct sockaddr *)&ss, sslen);
                        }
                }
-               handle(incoming, &in, addrlen);
        }
 }