frontend: Added module for generic connection handling.

diff --git a/src/Makefile.am b/src/Makefile.am
index de2f5cf642ef30c1eba8434256ea96bb89a66b5f..24b41ae51bedb40ba510eccb7f0f75d1731ce792 100644 (file)
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -26,6 +26,7 @@ libsysdb_la_SOURCES = \
                core/store.c include/core/store.h \
                include/core/data.h \
                core/error.c include/core/error.h \
+               frontend/connection.c include/frontend/connection.h \
                frontend/sock.c include/frontend/sock.h \
                utils/channel.c include/utils/channel.h \
                utils/llist.c include/utils/llist.h \

diff --git a/src/frontend/connection.c b/src/frontend/connection.c
new file mode 100644 (file)
index 0000000..028f377
--- /dev/null
+++ b/src/frontend/connection.c
@@ -0,0 +1,128 @@
+/*
+ * SysDB - src/frontend/connection.c
+ * Copyright (C) 2013 Sebastian 'tokkee' Harl <sh@tokkee.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "sysdb.h"
+#include "frontend/connection.h"
+#include "utils/strbuf.h"
+
+#include <assert.h>
+#include <errno.h>
+
+#include <arpa/inet.h>
+
+#include <string.h>
+
+/*
+ * connection handler functions
+ */
+
+static uint32_t
+connection_get_int32(sdb_conn_t *conn, size_t offset)
+{
+       const char *data;
+       uint32_t n;
+
+       assert(conn && (sdb_strbuf_len(conn->buf) >= offset + sizeof(uint32_t)));
+
+       data = sdb_strbuf_string(conn->buf);
+       memcpy(&n, data + offset, sizeof(n));
+       n = ntohl(n);
+       return n;
+} /* connection_get_int32 */
+
+static int
+command_handle(sdb_conn_t *conn)
+{
+       assert(conn && conn->cmd && conn->cmd_len);
+       /* XXX */
+       sdb_strbuf_skip(conn->buf, conn->cmd_len);
+       return 0;
+} /* command_handle */
+
+/* initialize the connection state information */
+static int
+command_init(sdb_conn_t *conn)
+{
+       assert(conn && (! conn->cmd) && (! conn->cmd_len));
+
+       conn->cmd = connection_get_int32(conn, 0);
+       conn->cmd_len = connection_get_int32(conn, sizeof(uint32_t));
+       sdb_strbuf_skip(conn->buf, 2 * sizeof(uint32_t));
+       return 0;
+} /* command_init */
+
+/* returns negative value on error, 0 on EOF, number of octets else */
+static ssize_t
+connection_read(sdb_conn_t *conn)
+{
+       ssize_t n = 0;
+
+       while (42) {
+               ssize_t status;
+
+               errno = 0;
+               status = sdb_strbuf_read(conn->buf, conn->fd, 1024);
+               if (status < 0) {
+                       if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
+                               break;
+                       return (int)status;
+               }
+               else if (! status) /* EOF */
+                       break;
+
+               n += status;
+       }
+
+       return n;
+} /* connection_read */
+
+/*
+ * public API
+ */
+
+ssize_t
+sdb_connection_read(sdb_conn_t *conn)
+{
+       ssize_t n = 0;
+
+       while (42) {
+               ssize_t status = connection_read(conn);
+               if (status <= 0)
+                       break;
+
+               n += status;
+
+               if (conn->cmd_len && (sdb_strbuf_len(conn->buf) >= conn->cmd_len))
+                       command_handle(conn);
+               else if (sdb_strbuf_len(conn->buf) >= 2 * sizeof(int32_t))
+                       command_init(conn);
+       }
+       return n;
+} /* sdb_connection_read */
+
+/* vim: set tw=78 sw=4 ts=4 noexpandtab : */
+

diff --git a/src/frontend/sock.c b/src/frontend/sock.c
index d7b2ee97324ddef9d32246f9be163ec30152f998..d11fc421669ee3535b6762f5a09d8d3e4227936a 100644 (file)
--- a/src/frontend/sock.c
+++ b/src/frontend/sock.c
@@ -28,6 +28,7 @@
 #include "sysdb.h"
 #include "core/error.h"
 #include "core/object.h"
+#include "frontend/connection.h"
 #include "frontend/sock.h"
 
 #include "utils/channel.h"
@@ -37,8 +38,6 @@
 #include <assert.h>
 #include <errno.h>
 
-#include <arpa/inet.h>
-
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -67,16 +66,10 @@ typedef struct {
        sdb_object_t super;
 
        /* connection and client information */
-       int fd;
        struct sockaddr_storage client_addr;
        socklen_t client_addr_len;
 
-       /* read buffer */
-       sdb_strbuf_t *buf;
-
-       /* state information for the currently executed command */
-       uint32_t cmd;
-       uint32_t cmd_len;
+       sdb_conn_t conn;
 } connection_obj_t;
 #define CONN(obj) ((connection_obj_t *)(obj))
 
@@ -298,18 +291,18 @@ connection_init(sdb_object_t *obj, va_list ap)
 
        sock_fd = va_arg(ap, int);
 
-       CONN(obj)->buf = sdb_strbuf_create(/* size = */ 128);
-       if (! CONN(obj)->buf) {
+       CONN(obj)->conn.buf = sdb_strbuf_create(/* size = */ 128);
+       if (! CONN(obj)->conn.buf) {
                sdb_log(SDB_LOG_ERR, "frontend: Failed to allocate a read buffer "
                                "for a new remote connection");
                return -1;
        }
 
        conn->client_addr_len = sizeof(conn->client_addr);
-       conn->fd = accept(sock_fd, (struct sockaddr *)&conn->client_addr,
+       conn->conn.fd = accept(sock_fd, (struct sockaddr *)&conn->client_addr,
                        &conn->client_addr_len);
 
-       if (conn->fd < 0) {
+       if (conn->conn.fd < 0) {
                char buf[1024];
                sdb_log(SDB_LOG_ERR, "frontend: Failed to accept remote "
                                "connection: %s", sdb_strerror(errno,
@@ -323,21 +316,21 @@ connection_init(sdb_object_t *obj, va_list ap)
                return -1;
        }
 
-       sock_fl = fcntl(conn->fd, F_GETFL);
-       if (fcntl(conn->fd, F_SETFL, sock_fl | O_NONBLOCK)) {
+       sock_fl = fcntl(conn->conn.fd, F_GETFL);
+       if (fcntl(conn->conn.fd, F_SETFL, sock_fl | O_NONBLOCK)) {
                char buf[1024];
                sdb_log(SDB_LOG_ERR, "frontend: Failed to switch connection conn#%i "
-                               "to non-blocking mode: %s", conn->fd,
+                               "to non-blocking mode: %s", conn->conn.fd,
                                sdb_strerror(errno, buf, sizeof(buf)));
                return -1;
        }
 
        sdb_log(SDB_LOG_DEBUG, "frontend: Accepted connection on fd=%i",
-                       conn->fd);
+                       conn->conn.fd);
 
        /* update the object name */
        snprintf(obj->name + strlen(CONN_FD_PREFIX),
-                       strlen(CONN_FD_PLACEHOLDER), "%i", conn->fd);
+                       strlen(CONN_FD_PLACEHOLDER), "%i", conn->conn.fd);
        return 0;
 } /* connection_init */
 
@@ -350,16 +343,17 @@ connection_destroy(sdb_object_t *obj)
        assert(obj);
        conn = CONN(obj);
 
-       len = sdb_strbuf_len(conn->buf);
+       len = sdb_strbuf_len(conn->conn.buf);
        if (len)
                sdb_log(SDB_LOG_INFO, "frontend: Discarding incomplete command "
                                "(%zu bytes left in buffer)", len);
 
-       sdb_log(SDB_LOG_DEBUG, "frontend: Closing connection on fd=%i", conn->fd);
-       close(conn->fd);
-       conn->fd = -1;
+       sdb_log(SDB_LOG_DEBUG, "frontend: Closing connection on fd=%i",
+                       conn->conn.fd);
+       close(conn->conn.fd);
+       conn->conn.fd = -1;
 
-       sdb_strbuf_destroy(CONN(obj)->buf);
+       sdb_strbuf_destroy(CONN(obj)->conn.buf);
 } /* connection_destroy */
 
 static sdb_type_t connection_type = {
@@ -372,66 +366,6 @@ static sdb_type_t connection_type = {
  * connection handler functions
  */
 
-static uint32_t
-connection_get_int32(connection_obj_t *conn, size_t offset)
-{
-       const char *data;
-       uint32_t n;
-
-       assert(conn && (sdb_strbuf_len(conn->buf) >= offset + sizeof(uint32_t)));
-
-       data = sdb_strbuf_string(conn->buf);
-       memcpy(&n, data + offset, sizeof(n));
-       n = ntohl(n);
-       return n;
-} /* connection_get_int32 */
-
-static int
-command_handle(connection_obj_t *conn)
-{
-       assert(conn && conn->cmd && conn->cmd_len);
-       /* XXX */
-       sdb_strbuf_skip(conn->buf, conn->cmd_len);
-       return 0;
-} /* command_handle */
-
-/* initialize the connection state information */
-static int
-command_init(connection_obj_t *conn)
-{
-       assert(conn && (! conn->cmd) && (! conn->cmd_len));
-
-       conn->cmd = connection_get_int32(conn, 0);
-       conn->cmd_len = connection_get_int32(conn, sizeof(uint32_t));
-       sdb_strbuf_skip(conn->buf, 2 * sizeof(uint32_t));
-       return 0;
-} /* command_init */
-
-/* returns negative value on error, 0 on EOF, number of octets else */
-static ssize_t
-connection_read(connection_obj_t *conn)
-{
-       ssize_t n = 0;
-
-       while (42) {
-               ssize_t status;
-
-               errno = 0;
-               status = sdb_strbuf_read(conn->buf, conn->fd, 1024);
-               if (status < 0) {
-                       if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
-                               return n;
-                       return (int)status;
-               }
-               else if (! status) /* EOF */
-                       return n;
-
-               n += status;
-       }
-
-       return n;
-} /* connection_read */
-
 static void *
 connection_handler(void *data)
 {
@@ -460,18 +394,13 @@ connection_handler(void *data)
                        continue;
                }
 
-               status = (int)connection_read(conn);
+               status = (int)sdb_connection_read(&conn->conn);
                if (status <= 0) {
                        /* error or EOF -> close connection */
                        sdb_object_deref(SDB_OBJ(conn));
                        continue;
                }
 
-               if (conn->cmd_len && (sdb_strbuf_len(conn->buf) >= conn->cmd_len))
-                       command_handle(conn);
-               else if (sdb_strbuf_len(conn->buf) >= 2 * sizeof(int32_t))
-                       command_init(conn);
-
                /* return the connection to the main loop */
                if (sdb_llist_append(sock->open_connections, SDB_OBJ(conn))) {
                        sdb_log(SDB_LOG_ERR, "frontend: Failed to re-append "
@@ -534,11 +463,11 @@ socket_handle_incoming(sdb_fe_socket_t *sock,
        while (sdb_llist_iter_has_next(iter)) {
                sdb_object_t *obj = sdb_llist_iter_get_next(iter);
 
-               if (FD_ISSET(CONN(obj)->fd, exceptions))
+               if (FD_ISSET(CONN(obj)->conn.fd, exceptions))
                        sdb_log(SDB_LOG_INFO, "Exception on fd %d",
-                                       CONN(obj)->fd);
+                                       CONN(obj)->conn.fd);
 
-               if (FD_ISSET(CONN(obj)->fd, ready)) {
+               if (FD_ISSET(CONN(obj)->conn.fd, ready)) {
                        sdb_llist_iter_remove_current(iter);
                        sdb_channel_write(sock->chan, &obj);
                }
@@ -664,11 +593,11 @@ sdb_fe_sock_listen_and_serve(sdb_fe_socket_t *sock, sdb_fe_loop_t *loop)
 
                while (sdb_llist_iter_has_next(iter)) {
                        sdb_object_t *obj = sdb_llist_iter_get_next(iter);
-                       FD_SET(CONN(obj)->fd, &ready);
-                       FD_SET(CONN(obj)->fd, &exceptions);
+                       FD_SET(CONN(obj)->conn.fd, &ready);
+                       FD_SET(CONN(obj)->conn.fd, &exceptions);
 
-                       if (CONN(obj)->fd > max_fd)
-                               max_fd = CONN(obj)->fd;
+                       if (CONN(obj)->conn.fd > max_fd)
+                               max_fd = CONN(obj)->conn.fd;
                }
                sdb_llist_iter_destroy(iter);
 

diff --git a/src/include/frontend/connection.h b/src/include/frontend/connection.h
new file mode 100644 (file)
index 0000000..7726e75
--- /dev/null
+++ b/src/include/frontend/connection.h
@@ -0,0 +1,70 @@
+/*
+ * SysDB - src/include/frontend/connection.h
+ * Copyright (C) 2013 Sebastian 'tokkee' Harl <sh@tokkee.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef SDB_FRONTEND_CONNECTION_H
+#define SDB_FRONTEND_CONNECTION_H 1
+
+#include "utils/strbuf.h"
+
+#include <inttypes.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* a generic connection object */
+typedef struct {
+       /* file-descriptor of the open connection */
+       int fd;
+
+       /* read buffer */
+       sdb_strbuf_t *buf;
+
+       /* connection / protocol state information */
+       uint32_t cmd;
+       uint32_t cmd_len;
+} sdb_conn_t;
+
+/*
+ * sdb_connection_read:
+ * Read from an open connection until reading would block.
+ *
+ * Returns:
+ *  - the number of bytes read (0 on EOF)
+ *  - a negative value on error
+ */
+ssize_t
+sdb_connection_read(sdb_conn_t *conn);
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif /* ! SDB_FRONTEND_CONNECTION_H */
+
+/* vim: set tw=78 sw=4 ts=4 noexpandtab : */
+