first alpha version of libvncclient

1 files changed, 424 insertions, 0 deletions

diff --git a/libvncclient/sockets.c b/libvncclient/sockets.c
new file mode 100644
index 0000000..5e6cd69
--- /dev/null
+++ b/libvncclient/sockets.c
@@ -0,0 +1,424 @@
+/*
+ *  Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.
+ *
+ *  This 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 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This software 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 this software; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ *  USA.
+ */
+
+/*
+ * sockets.c - functions to deal with sockets.
+ */
+
+#include <unistd.h>
+#include <sys/socket.h>
+#include <errno.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <fcntl.h>
+#include <assert.h>
+#include <rfb/rfbclient.h>
+
+void PrintInHex(char *buf, int len);
+
+Bool errorMessageOnReadFailure = TRUE;
+
+#define BUF_SIZE 8192
+static char buf[BUF_SIZE];
+static char *bufoutptr = buf;
+static int buffered = 0;
+
+/*
+ * ReadFromRFBServer is called whenever we want to read some data from the RFB
+ * server.  It is non-trivial for two reasons:
+ *
+ * 1. For efficiency it performs some intelligent buffering, avoiding invoking
+ *    the read() system call too often.  For small chunks of data, it simply
+ *    copies the data out of an internal buffer.  For large amounts of data it
+ *    reads directly into the buffer provided by the caller.
+ *
+ * 2. Whenever read() would block, it invokes the Xt event dispatching
+ *    mechanism to process X events.  In fact, this is the only place these
+ *    events are processed, as there is no XtAppMainLoop in the program.
+ */
+
+Bool
+ReadFromRFBServer(rfbClient* client, char *out, unsigned int n)
+{
+  if (n <= buffered) {
+    memcpy(out, bufoutptr, n);
+    bufoutptr += n;
+    buffered -= n;
+    return TRUE;
+  }
+
+  memcpy(out, bufoutptr, buffered);
+
+  out += buffered;
+  n -= buffered;
+
+  bufoutptr = buf;
+  buffered = 0;
+
+  if (n <= BUF_SIZE) {
+
+    while (buffered < n) {
+      int i = read(client->sock, buf + buffered, BUF_SIZE - buffered);
+      if (i <= 0) {
+	if (i < 0) {
+	  if (errno == EWOULDBLOCK || errno == EAGAIN) {
+	    /* TODO:
+	       ProcessXtEvents();
+	    */
+	    i = 0;
+	  } else {
+	    perror("read");
+	    return FALSE;
+	  }
+	} else {
+	  if (errorMessageOnReadFailure) {
+	    fprintf(stderr,"VNC server closed connection\n");
+	  }
+	  return FALSE;
+	}
+      }
+      buffered += i;
+    }
+
+    memcpy(out, bufoutptr, n);
+    bufoutptr += n;
+    buffered -= n;
+    return TRUE;
+
+  } else {
+
+    while (n > 0) {
+      int i = read(client->sock, out, n);
+      if (i <= 0) {
+	if (i < 0) {
+	  if (errno == EWOULDBLOCK || errno == EAGAIN) {
+	    /* TODO:
+	       ProcessXtEvents();
+	    */
+	    i = 0;
+	  } else {
+	    perror("read");
+	    return FALSE;
+	  }
+	} else {
+	  if (errorMessageOnReadFailure) {
+	    fprintf(stderr,"VNC server closed connection\n");
+	  }
+	  return FALSE;
+	}
+      }
+      out += i;
+      n -= i;
+    }
+
+    return TRUE;
+  }
+}
+
+
+/*
+ * Write an exact number of bytes, and don't return until you've sent them.
+ */
+
+Bool
+WriteExact(rfbClient* client, char *buf, int n)
+{
+  fd_set fds;
+  int i = 0;
+  int j;
+
+  while (i < n) {
+    j = write(client->sock, buf + i, (n - i));
+    if (j <= 0) {
+      if (j < 0) {
+	if (errno == EWOULDBLOCK || errno == EAGAIN) {
+	  FD_ZERO(&fds);
+	  FD_SET(client->sock,&fds);
+
+	  if (select(client->sock+1, NULL, &fds, NULL, NULL) <= 0) {
+	    perror("select");
+	    return FALSE;
+	  }
+	  j = 0;
+	} else {
+	  perror("write");
+	  return FALSE;
+	}
+      } else {
+	fprintf(stderr,"write failed\n");
+	return FALSE;
+      }
+    }
+    i += j;
+  }
+  return TRUE;
+}
+
+
+/*
+ * ConnectToTcpAddr connects to the given TCP port.
+ */
+
+int
+ConnectToTcpAddr(unsigned int host, int port)
+{
+  int sock;
+  struct sockaddr_in addr;
+  int one = 1;
+
+  addr.sin_family = AF_INET;
+  addr.sin_port = htons(port);
+  addr.sin_addr.s_addr = host;
+
+  sock = socket(AF_INET, SOCK_STREAM, 0);
+  if (sock < 0) {
+    perror("ConnectToTcpAddr: socket");
+    return -1;
+  }
+
+  if (connect(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+    perror("ConnectToTcpAddr: connect");
+    close(sock);
+    return -1;
+  }
+
+  if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
+		 (char *)&one, sizeof(one)) < 0) {
+    perror("ConnectToTcpAddr: setsockopt");
+    close(sock);
+    return -1;
+  }
+
+  return sock;
+}
+
+
+
+/*
+ * FindFreeTcpPort tries to find unused TCP port in the range
+ * (TUNNEL_PORT_OFFSET, TUNNEL_PORT_OFFSET + 99]. Returns 0 on failure.
+ */
+
+int
+FindFreeTcpPort(void)
+{
+  int sock, port;
+  struct sockaddr_in addr;
+
+  addr.sin_family = AF_INET;
+  addr.sin_addr.s_addr = INADDR_ANY;
+
+  sock = socket(AF_INET, SOCK_STREAM, 0);
+  if (sock < 0) {
+    perror(": FindFreeTcpPort: socket");
+    return 0;
+  }
+
+  for (port = TUNNEL_PORT_OFFSET + 99; port > TUNNEL_PORT_OFFSET; port--) {
+    addr.sin_port = htons((unsigned short)port);
+    if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) == 0) {
+      close(sock);
+      return port;
+    }
+  }
+
+  close(sock);
+  return 0;
+}
+
+
+/*
+ * ListenAtTcpPort starts listening at the given TCP port.
+ */
+
+int
+ListenAtTcpPort(int port)
+{
+  int sock;
+  struct sockaddr_in addr;
+  int one = 1;
+
+  addr.sin_family = AF_INET;
+  addr.sin_port = htons(port);
+  addr.sin_addr.s_addr = INADDR_ANY;
+
+  sock = socket(AF_INET, SOCK_STREAM, 0);
+  if (sock < 0) {
+    perror("ListenAtTcpPort: socket");
+    return -1;
+  }
+
+  if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR,
+		 (const char *)&one, sizeof(one)) < 0) {
+    perror("ListenAtTcpPort: setsockopt");
+    close(sock);
+    return -1;
+  }
+
+  if (bind(sock, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
+    perror("ListenAtTcpPort: bind");
+    close(sock);
+    return -1;
+  }
+
+  if (listen(sock, 5) < 0) {
+    perror("ListenAtTcpPort: listen");
+    close(sock);
+    return -1;
+  }
+
+  return sock;
+}
+
+
+/*
+ * AcceptTcpConnection accepts a TCP connection.
+ */
+
+int
+AcceptTcpConnection(int listenSock)
+{
+  int sock;
+  struct sockaddr_in addr;
+  int addrlen = sizeof(addr);
+  int one = 1;
+
+  sock = accept(listenSock, (struct sockaddr *) &addr, &addrlen);
+  if (sock < 0) {
+    perror("AcceptTcpConnection: accept");
+    return -1;
+  }
+
+  if (setsockopt(sock, IPPROTO_TCP, TCP_NODELAY,
+		 (char *)&one, sizeof(one)) < 0) {
+    perror("AcceptTcpConnection: setsockopt");
+    close(sock);
+    return -1;
+  }
+
+  return sock;
+}
+
+
+/*
+ * SetNonBlocking sets a socket into non-blocking mode.
+ */
+
+Bool
+SetNonBlocking(int sock)
+{
+  if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0) {
+    perror("AcceptTcpConnection: fcntl");
+    return FALSE;
+  }
+  return TRUE;
+}
+
+
+/*
+ * StringToIPAddr - convert a host string to an IP address.
+ */
+
+Bool
+StringToIPAddr(const char *str, unsigned int *addr)
+{
+  struct hostent *hp;
+
+  if (strcmp(str,"") == 0) {
+    *addr = 0; /* local */
+    return TRUE;
+  }
+
+  *addr = inet_addr(str);
+
+  if (*addr != -1)
+    return TRUE;
+
+  hp = gethostbyname(str);
+
+  if (hp) {
+    *addr = *(unsigned int *)hp->h_addr;
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
+
+/*
+ * Test if the other end of a socket is on the same machine.
+ */
+
+Bool
+SameMachine(int sock)
+{
+  struct sockaddr_in peeraddr, myaddr;
+  int addrlen = sizeof(struct sockaddr_in);
+
+  getpeername(sock, (struct sockaddr *)&peeraddr, &addrlen);
+  getsockname(sock, (struct sockaddr *)&myaddr, &addrlen);
+
+  return (peeraddr.sin_addr.s_addr == myaddr.sin_addr.s_addr);
+}
+
+
+/*
+ * Print out the contents of a packet for debugging.
+ */
+
+void
+PrintInHex(char *buf, int len)
+{
+  int i, j;
+  char c, str[17];
+
+  str[16] = 0;
+
+  fprintf(stderr,"ReadExact: ");
+
+  for (i = 0; i < len; i++)
+    {
+      if ((i % 16 == 0) && (i != 0)) {
+	fprintf(stderr,"           ");
+      }
+      c = buf[i];
+      str[i % 16] = (((c > 31) && (c < 127)) ? c : '.');
+      fprintf(stderr,"%02x ",(unsigned char)c);
+      if ((i % 4) == 3)
+	fprintf(stderr," ");
+      if ((i % 16) == 15)
+	{
+	  fprintf(stderr,"%s\n",str);
+	}
+    }
+  if ((i % 16) != 0)
+    {
+      for (j = i % 16; j < 16; j++)
+	{
+	  fprintf(stderr,"   ");
+	  if ((j % 4) == 3) fprintf(stderr," ");
+	}
+      str[i % 16] = 0;
+      fprintf(stderr,"%s\n",str);
+    }
+
+  fflush(stderr);
+}