check for fork() and not __uClinux__

configure.in

@@ -616,7 +616,7 @@ AC_PROG_GCC_TRADITIONAL
 AC_FUNC_MEMCMP
 AC_FUNC_SELECT_ARGTYPES
 AC_TYPE_SIGNAL
-AC_CHECK_FUNCS([dup2 getspnam getusershell memset putenv select socket strdup clearenv strlcpy strlcat daemon basename _getpty getaddrinfo freeaddrinfo getnameinfo])
+AC_CHECK_FUNCS([dup2 getspnam getusershell memset putenv select socket strdup clearenv strlcpy strlcat daemon basename _getpty getaddrinfo freeaddrinfo getnameinfo fork])
 
 AC_SEARCH_LIBS(basename, gen, AC_DEFINE(HAVE_BASENAME))
 

dbutil.c

@@ -443,7 +443,7 @@ int spawn_command(void(*exec_fn)(void *user_data), void *exec_data,
 		return DROPBEAR_FAILURE;
 	}
 
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	pid = vfork();
 #else
 	pid = fork();

scp.c

@@ -130,22 +130,22 @@ do_local_cmd(arglist *a)
 			fprintf(stderr, " %s", a->list[i]);
 		fprintf(stderr, "\n");
 	}
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	pid = vfork();
 #else
 	pid = fork();
-#endif /* __uClinux__ */
+#endif
 	if (pid == -1)
 		fatal("do_local_cmd: fork: %s", strerror(errno));
 
 	if (pid == 0) {
 		execvp(a->list[0], a->list);
 		perror(a->list[0]);
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 		_exit(1);
 #else
 		exit(1);
-#endif /* __uClinux__ */
+#endif
 	}
 
 	do_cmd_pid = pid;
@@ -171,6 +171,16 @@ do_local_cmd(arglist *a)
  * assigns the input and output file descriptors on success.
  */
 
+static void
+arg_setup(char *host, char *remuser, char *cmd)
+{
+	replacearg(&args, 0, "%s", ssh_program);
+	if (remuser != NULL)
+		addargs(&args, "-l%s", remuser);
+	addargs(&args, "%s", host);
+	addargs(&args, "%s", cmd);
+}
+
 int
 do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout, int argc)
 {
@@ -198,22 +208,18 @@ do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout, int argc)
 	close(reserved[0]);
 	close(reserved[1]);
 
-    /* uClinux needs to build the args here before vforking,
-       otherwise we do it later on. */
-#ifdef __uClinux__
-		replacearg(&args, 0, "%s", ssh_program);
-		if (remuser != NULL)
-			addargs(&args, "-l%s", remuser);
-		addargs(&args, "%s", host);
-		addargs(&args, "%s", cmd);
-#endif /* __uClinux__ */
+	/* uClinux needs to build the args here before vforking,
+	   otherwise we do it later on. */
+#ifndef HAVE_FORK
+	arg_setup(host, remuser, cmd);
+#endif
 
 	/* Fork a child to execute the command on the remote host using ssh. */
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	do_cmd_pid = vfork();
 #else
 	do_cmd_pid = fork();
-#endif /* __uClinux__ */
+#endif
 
 	if (do_cmd_pid == 0) {
 		/* Child. */
@@ -224,27 +230,22 @@ do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout, int argc)
 		close(pin[0]);
 		close(pout[1]);
 
-#ifndef __uClinux__
-		replacearg(&args, 0, "%s", ssh_program);
-		if (remuser != NULL)
-			addargs(&args, "-l%s", remuser);
-		addargs(&args, "%s", host);
-		addargs(&args, "%s", cmd);
-#endif /* __uClinux__ */
+#ifndef HAVE_FORK
+		arg_setup(host, remuser, cmd);
+#endif
 
 		execvp(ssh_program, args.list);
 		perror(ssh_program);
-#ifndef __uClinux__
-		exit(1);
-#else
+#ifndef HAVE_FORK
 		_exit(1);
-#endif /* __uClinux__ */
+#else
+		exit(1);
+#endif
 	} else if (do_cmd_pid == -1) {
 		fatal("fork: %s", strerror(errno));
 	}
 
-
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	/* clean up command */
 	/* pop cmd */
 	xfree(args.list[args.num-1]);
@@ -260,7 +261,7 @@ do_cmd(char *host, char *remuser, char *cmd, int *fdin, int *fdout, int argc)
 		args.list[args.num-1]=NULL;
 		args.num--;
 	}
-#endif /* __uClinux__ */
+#endif
 
 	/* Parent.  Close the other side, and return the local side. */
 	close(pin[0]);

session.h

@@ -218,7 +218,7 @@ struct serversession {
 	/* The resolved remote address, used for lastlog etc */
 	char *remotehost;
 
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	pid_t server_pid;
 #endif
 

svr-chansession.c

@@ -658,7 +658,7 @@ static int sessioncommand(struct Channel *channel, struct ChanSess *chansess,
 
 	/* uClinux will vfork(), so there'll be a race as 
 	connection_string is freed below. */
-#ifndef __uClinux__
+#ifdef HAVE_FORK
 	chansess->connection_string = make_connection_string();
 #endif
 
@@ -670,7 +670,7 @@ static int sessioncommand(struct Channel *channel, struct ChanSess *chansess,
 		ret = ptycommand(channel, chansess);
 	}
 
-#ifndef __uClinux__	
+#ifdef HAVE_FORK	
 	m_free(chansess->connection_string);
 #endif
 
@@ -745,7 +745,7 @@ static int ptycommand(struct Channel *channel, struct ChanSess *chansess) {
 		return DROPBEAR_FAILURE;
 	}
 	
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	pid = vfork();
 #else
 	pid = fork();
@@ -863,9 +863,9 @@ static void execchild(void *user_data) {
 	struct ChanSess *chansess = user_data;
 	char *usershell = NULL;
 
-    /* with uClinux we'll have vfork()ed, so don't want to overwrite the
-     * hostkey. can't think of a workaround to clear it */
-#ifndef __uClinux__
+	/* with uClinux we'll have vfork()ed, so don't want to overwrite the
+	 * hostkey. can't think of a workaround to clear it */
+#ifdef HAVE_FORK
 	/* wipe the hostkey */
 	sign_key_free(svr_opts.hostkey);
 	svr_opts.hostkey = NULL;

svr-session.c

@@ -84,7 +84,7 @@ void svr_session(int sock, int childpipe) {
 
 	/* Initialise server specific parts of the session */
 	svr_ses.childpipe = childpipe;
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	svr_ses.server_pid = getpid();
 #endif
 	svr_authinitialise();
@@ -157,7 +157,7 @@ void svr_dropbear_exit(int exitcode, const char* format, va_list param) {
 
 	_dropbear_log(LOG_INFO, fmtbuf, param);
 
-#ifdef __uClinux__
+#ifndef HAVE_FORK
 	/* only the main server process should cleanup - we don't want
 	 * forked children doing that */
 	if (svr_ses.server_pid == getpid())