add attach()/detach() support

[catagits/fcgi2.git] / libfcgi / os_unix.c

diff --git a/libfcgi/os_unix.c b/libfcgi/os_unix.c
index ccc3836..6d7dc53 100755 (executable)
--- a/libfcgi/os_unix.c
+++ b/libfcgi/os_unix.c
@@ -17,7 +17,7 @@
  */
 
 #ifndef lint
-static const char rcsid[] = "$Id: os_unix.c,v 1.27 2001/06/22 13:13:41 robs Exp $";
+static const char rcsid[] = "$Id: os_unix.c,v 1.38 2003/06/22 00:16:43 robs Exp $";
 #endif /* not lint */
 
 #include "fcgi_config.h"
@@ -41,6 +41,7 @@ static const char rcsid[] = "$Id: os_unix.c,v 1.27 2001/06/22 13:13:41 robs Exp
 #include <string.h>
 #include <sys/time.h>
 #include <sys/un.h>
+#include <signal.h>
 
 #ifdef HAVE_NETDB_H
 #include <netdb.h>
@@ -55,8 +56,6 @@ static const char rcsid[] = "$Id: os_unix.c,v 1.27 2001/06/22 13:13:41 robs Exp
 #endif
 
 #include "fastcgi.h"
-#include "fcgiapp.h"
-#include "fcgiappmisc.h"
 #include "fcgimisc.h"
 #include "fcgios.h"
 
@@ -101,6 +100,50 @@ static fd_set writeFdSetPost;
 static int numWrPosted = 0;
 static int volatile maxFd = -1;
 
+static int shutdownPending = FALSE;
+static int shutdownNow = FALSE;
+
+void OS_ShutdownPending()
+{
+    shutdownPending = TRUE;
+}
+
+static void OS_Sigusr1Handler(int signo)
+{
+    OS_ShutdownPending();
+}
+
+static void OS_SigpipeHandler(int signo)
+{
+    ;
+}
+
+static void installSignalHandler(int signo, const struct sigaction * act, int force)
+{
+    struct sigaction sa;
+
+    sigaction(signo, NULL, &sa);
+
+    if (force || sa.sa_handler == SIG_DFL) 
+    {
+        sigaction(signo, act, NULL);
+    }
+}
+
+static void OS_InstallSignalHandlers(int force)
+{
+    struct sigaction sa;
+
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = 0;
+
+    sa.sa_handler = OS_SigpipeHandler;
+    installSignalHandler(SIGPIPE, &sa, force);
+
+    sa.sa_handler = OS_Sigusr1Handler;
+    installSignalHandler(SIGUSR1, &sa, force);
+}
+
 /*
  *--------------------------------------------------------------
  *
@@ -137,7 +180,11 @@ int OS_LibInit(int stdioFds[3])
     FD_ZERO(&writeFdSet);
     FD_ZERO(&readFdSetPost);
     FD_ZERO(&writeFdSetPost);
+
+    OS_InstallSignalHandlers(FALSE);
+
     libInitialized = TRUE;
+
     return 0;
 }
 
@@ -238,11 +285,11 @@ union SockAddrUnion {
 int OS_CreateLocalIpcFd(const char *bindPath, int backlog)
 {
     int listenSock, servLen;
-    union   SockAddrUnion sa;
+    union   SockAddrUnion sa;  
     int            tcp = FALSE;
-    unsigned long tcp_ia;
+    unsigned long tcp_ia = 0;
     char    *tp;
-    short   port;
+    short   port = 0;
     char    host[MAXPATHLEN];
 
     strcpy(host, bindPath);
@@ -345,7 +392,7 @@ int OS_FcgiConnect(char *bindPath)
     int connectStatus;
     char    *tp;
     char    host[MAXPATHLEN];
-    short   port;
+    short   port = 0;
     int            tcp = FALSE;
 
     strcpy(host, bindPath);
@@ -409,6 +456,7 @@ int OS_FcgiConnect(char *bindPath)
  */
 int OS_Read(int fd, char * buf, size_t len)
 {
+    if (shutdownNow) return -1;
     return(read(fd, buf, len));
 }
 
@@ -430,6 +478,7 @@ int OS_Read(int fd, char * buf, size_t len)
  */
 int OS_Write(int fd, char * buf, size_t len)
 {
+    if (shutdownNow) return -1;
     return(write(fd, buf, len));
 }
 
@@ -589,7 +638,7 @@ int OS_AsyncRead(int fd, int offset, void *buf, int len,
     if(fd > maxFd)
         maxFd = fd;
 
-    if(index >= asyncIoTableSize) {
+    while (index >= asyncIoTableSize) {
         GrowAsyncTable();
     }
 
@@ -638,7 +687,7 @@ int OS_AsyncWrite(int fd, int offset, void *buf, int len,
     if(fd > maxFd)
         maxFd = fd;
 
-    if(index >= asyncIoTableSize) {
+    while (index >= asyncIoTableSize) {
         GrowAsyncTable();
     }
 
@@ -670,7 +719,7 @@ int OS_AsyncWrite(int fd, int offset, void *buf, int len,
  *
  *--------------------------------------------------------------
  */
-int OS_Close(int fd)
+int OS_Close(int fd, int shutdown_ok)
 {
     if (fd == -1)
         return 0;
@@ -695,6 +744,37 @@ int OS_Close(int fd)
             maxFd--;
         }
     }
+
+    /*
+     * shutdown() the send side and then read() from client until EOF
+     * or a timeout expires.  This is done to minimize the potential
+     * that a TCP RST will be sent by our TCP stack in response to 
+     * receipt of additional data from the client.  The RST would
+     * cause the client to discard potentially useful response data.
+     */
+
+    if (shutdown_ok)
+    {
+        if (shutdown(fd, 1) == 0)
+        {
+            struct timeval tv;
+            fd_set rfds;
+            int rv;
+            char trash[1024];
+
+            FD_ZERO(&rfds);
+
+            do 
+            {
+                FD_SET(fd, &rfds);
+                tv.tv_sec = 2;
+                tv.tv_usec = 0;
+                rv = select(fd + 1, &rfds, NULL, NULL, &tv);
+            }
+            while (rv > 0 && read(fd, trash, sizeof(trash)) > 0);
+        }
+    }
+
     return close(fd);
 }
 
@@ -921,7 +1001,9 @@ static int AcquireLock(int sock, int fail_on_intr)
 
         if (fcntl(sock, F_SETLKW, &lock) != -1)
             return 0;
-    } while (errno == EINTR && !fail_on_intr);
+    } while (errno == EINTR 
+             && ! fail_on_intr 
+             && ! shutdownPending);
 
     return -1;
 
@@ -1064,7 +1146,7 @@ static int is_af_unix_keeper(const int fd)
  */
 int OS_Accept(int listen_sock, int fail_on_intr, const char *webServerAddrs)
 {
-    int socket;
+    int socket = -1;
     union {
         struct sockaddr_un un;
         struct sockaddr_in in;
@@ -1081,14 +1163,25 @@ int OS_Accept(int listen_sock, int fail_on_intr, const char *webServerAddrs)
 #else
                 int len = sizeof(sa);
 #endif
+                if (shutdownPending) break;
+                /* There's a window here */
+
                 socket = accept(listen_sock, (struct sockaddr *)&sa, &len);
-            } while (socket < 0 && errno == EINTR && !fail_on_intr);
+            } while (socket < 0 
+                     && errno == EINTR 
+                     && ! fail_on_intr 
+                     && ! shutdownPending);
 
             if (socket < 0) {
-                if (!is_reasonable_accept_errno(errno)) {
+                if (shutdownPending || ! is_reasonable_accept_errno(errno)) {
                     int errnoSave = errno;
+
                     ReleaseLock(listen_sock);
-                    errno = errnoSave;
+                    
+                    if (! shutdownPending) {
+                        errno = errnoSave;
+                    }
+
                     return (-1);
                 }
                 errno = 0;
@@ -1139,9 +1232,9 @@ int OS_Accept(int listen_sock, int fail_on_intr, const char *webServerAddrs)
  *
  *----------------------------------------------------------------------
  */
-int OS_IpcClose(int ipcFd)
+int OS_IpcClose(int ipcFd, int shutdown)
 {
-    return OS_Close(ipcFd);
+    return OS_Close(ipcFd, shutdown);
 }
 
 /*