This patch adds a "server" abstract base class for listening
on a port, for use by the later patches to implement an LSP server.
It's largely adapted from examples in glibc's docs. I suspect that
I've introduced platform-specific assumptions (and that it may need some
extra configure tests for the extra functionality), but this part of
the kit is just a proof-of-concept.
gcc/ChangeLog:
* Makefile.in (OBJS): Add server.o.
* server.c: New file.
* server.h: New file.
---
gcc/Makefile.in | 1 +
gcc/server.c | 152 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
gcc/server.h | 46 +++++++++++++++++
3 files changed, 199 insertions(+)
create mode 100644 gcc/server.c
create mode 100644 gcc/server.h
diff --git a/gcc/Makefile.in b/gcc/Makefile.in
index 77ecbd6..4e60bc0 100644
--- a/gcc/Makefile.in
+++ b/gcc/Makefile.in
@@ -1454,6 +1454,7 @@ OBJS = \
sel-sched.o \
selftest-rtl.o \
selftest-run-tests.o \
+ server.o \
sese.o \
shrink-wrap.o \
simplify-rtx.o \
diff --git a/gcc/server.c b/gcc/server.c
new file mode 100644
index 0000000..871a95f
--- /dev/null
+++ b/gcc/server.c
@@ -0,0 +1,152 @@
+/* Abstract server implementation.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "server.h"
+
+/* adapted from GNU libc docs. */
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netdb.h>
+#include <arpa/inet.h>
+
+#define MAXMSG 512
+
+static int
+make_socket (uint16_t port)
+{
+ int sock;
+ struct sockaddr_in name;
+
+ /* Create the socket. */
+ sock = socket (PF_INET, SOCK_STREAM, 0);
+ if (sock < 0)
+ {
+ perror ("socket");
+ exit (EXIT_FAILURE);
+ }
+
+ /* Give the socket a name. */
+ name.sin_family = AF_INET;
+ name.sin_port = htons (port);
+ name.sin_addr.s_addr = htonl (INADDR_ANY);
+ if (bind (sock, (struct sockaddr *) &name, sizeof (name)) < 0)
+ {
+ perror ("bind");
+ exit (EXIT_FAILURE);
+ }
+
+ return sock;
+}
+
+/* Serve on PORT. */
+
+void
+server::serve (int port)
+{
+ int sock;
+ fd_set active_fd_set, read_fd_set;
+ int i;
+ struct sockaddr_in clientname;
+ socklen_t size;
+
+ /* Create the socket and set it up to accept connections. */
+ sock = make_socket (port);
+ if (listen (sock, 1) < 0)
+ {
+ perror ("listen");
+ exit (EXIT_FAILURE);
+ }
+
+ /* Initialize the set of active sockets. */
+ FD_ZERO (&active_fd_set);
+ FD_SET (sock, &active_fd_set);
+
+ while (1)
+ {
+ /* Block until input arrives on one or more active sockets. */
+ read_fd_set = active_fd_set;
+ if (select (FD_SETSIZE, &read_fd_set, NULL, NULL, NULL) < 0)
+ {
+ perror ("select");
+ exit (EXIT_FAILURE);
+ }
+
+ /* Service all the sockets with input pending. */
+ for (i = 0; i < FD_SETSIZE; ++i)
+ if (FD_ISSET (i, &read_fd_set))
+ {
+ if (i == sock)
+ {
+ /* Connection request on original socket. */
+ int new_;
+ size = sizeof (clientname);
+ new_ = accept (sock,
+ (struct sockaddr *) &clientname,
+ &size);
+ if (new_ < 0)
+ {
+ perror ("accept");
+ exit (EXIT_FAILURE);
+ }
+ fprintf (stderr,
+ "Server: connect from host %s, port %hd.\n",
+ inet_ntoa (clientname.sin_addr),
+ ntohs (clientname.sin_port));
+ FD_SET (new_, &active_fd_set);
+ }
+ else
+ {
+ /* Data arriving on an already-connected socket. */
+ if (read_from_client (file_descriptor (i)) < 0)
+ {
+ close (i);
+ FD_CLR (i, &active_fd_set);
+ }
+ }
+ }
+ }
+}
+
+int
+server::read_from_client (file_descriptor fd)
+{
+ char buffer[MAXMSG];
+ int nbytes;
+
+ nbytes = read (fd.m_fd, buffer, MAXMSG);
+ if (nbytes < 0)
+ {
+ /* Read error. */
+ perror ("read");
+ exit (EXIT_FAILURE);
+ }
+ else if (nbytes == 0)
+ /* End-of-file. */
+ return -1;
+ else
+ {
+ /* Data read. */
+ on_read (fd, nbytes, buffer);
+ return 0;
+ }
+}
diff --git a/gcc/server.h b/gcc/server.h
new file mode 100644
index 0000000..3bcf9f6e
--- /dev/null
+++ b/gcc/server.h
@@ -0,0 +1,46 @@
+/* Abstract server implementation.
+ Copyright (C) 2017 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
+
+#ifndef GCC_SERVER_H
+#define GCC_SERVER_H
+
+/* Wrapper aroung "int" for file descriptors. */
+
+struct file_descriptor
+{
+ explicit file_descriptor (int fd) : m_fd (fd) {}
+
+ int m_fd;
+};
+
+/* Abstract base class for implementing a server. */
+
+class server
+{
+ public:
+ virtual ~server () {}
+ void serve (int port);
+
+ virtual void on_read (file_descriptor fd, size_t length, const char *buf) =
0;
+
+ private:
+ int read_from_client (file_descriptor fd);
+};
+
+#endif /* GCC_SERVER_H */
--
1.8.5.3
