Add Swift daemon API, use in 'servaldswift'

The daemon API is built as a Swift module called ServalDNA.

The new CliContext class allows easy implementation of CLI output using
Swift code.  The new CliContextFile subclass is the obvious first
implementation, equivalent to cli_stdio.c.  The 'servaldswift'
executable now uses CliContextFile to print its CLI output to standard
output.

The new delegated log output support constructs each log line in a
buffer and prints it by calling the delegate's 'print' function at
end-of-line.  The 'servaldswift' executable now provides a log output
delegate in Swift that simply prints to standard error, replacing
log_output_console.o, which is omitted from its link.

.gitignore

@@ -11,6 +11,8 @@
 *.a
 *.suo
 .*.sw?
+*.swiftdoc
+*.swiftmodule
 /VERSION.txt
 /configure
 /autom4te.cache
@@ -37,6 +39,7 @@ test.*.log
 /java-api/Makefile
 /java-api/classes/
 /java-api/testclasses/
+/swift-daemon-api/build/
 /swift-client-api/Makefile
 /swift-client-api/build/
 /swift-client-api/swift-client-util

INSTALL.md

@@ -259,6 +259,11 @@ present][Swift development]:
   Swift language's run-time support and resultant library dependencies, so is
   not suitable for deployment.
 
+* **ServalDNA.swiftmodule**  
+  **ServalDNA.swiftdoc**  
+  **libServalDNA.a**  
+  are the [Swift Daemon API module][].
+
 * **swift-client-api/build/debug/ServalClient.swiftmodule**  
   **swift-client-api/build/debug/ServalClient.swiftdoc**  
   **swift-client-api/build/debug/libServalClient.a**  
@@ -330,6 +335,7 @@ This document is available under the [Creative Commons Attribution 4.0 Internati
 [gcc 6]: http://gcc.gnu.org/gcc-6/
 [Notes for Developers]: ./doc/Development.md
 [Swift development]: ./doc/Development.md#swift
+[Swift Daemon API module]: ./doc/Development.md#swift-daemon-api
 [Swift Client API module]: ./doc/Development.md#swift-client-api
 [OpenWRT]: ./doc/OpenWRT.md
 [Serval Infrastructure]: ./doc/Serval-Infrastructure.md

Makefile.in

@@ -1,4 +1,5 @@
 # Makefile.in for Serval DNA daemon and libraries
+# nnnn
 # vim: noet ts=8 sts=0 sw=8
 prefix=@prefix@
 exec_prefix=@exec_prefix@
@@ -7,16 +8,24 @@ sbindir=@sbindir@
 sysconfdir=@sysconfdir@
 localstatedir=@localstatedir@
 srcdir=@srcdir@
+abs_srcdir=@abs_srcdir@
+abs_builddir=@abs_builddir@
 
 CC = 			@CC@
 AR =			@AR@
 RANLIB =		@RANLIB@
 JAVAC= 			@JAVAC@
-SWIFTC= 		@SWIFTC@
 
-SWIFTCFLAGS= 		@SWIFTCFLAGS@ -I. -I $(srcdir)
+SWIFTC= 		@SWIFTC@
+SWIFTCFLAGS= 		@SWIFTCFLAGS@ -I$(abs_builddir) -I$(abs_srcdir)
 SWIFTLIBS=		@LIBS@
+
+SWIFT_BUILD= 		@SWIFT_BUILD@
+SWIFT_BUILD_FLAGS= 	$(addprefix -Xswiftc , $(SWIFTCFLAGS)) 
+
 SWIFT_MODULE_NAME=	ServalDNA
+SWIFT_PACKAGE_DIR=	$(srcdir)/swift-daemon-api
+SWIFT_BUILD_DIR=	$(abs_builddir)/swift-daemon-api/build
 
 INSTALL=        	install
 INSTALL_PROGRAM=	$(INSTALL)
@@ -166,13 +175,26 @@ endif # $(JAVAC)
 
 ifneq ($(SWIFTC),) # Only provide Swift targets if the Swift compiler is available.
 
-all:	swift-client-api
+all:	swift-daemon-api swift-client-api
 
 test:	servaldswift
 
-clean:	swift-client-api-clean
+clean:	swift-daemon-api-clean swift-client-api-clean
 
-.PHONY: swift-client-api swift-client-api-clean
+.PHONY: swift-daemon-api swift-daemon-api-clean swift-client-api swift-client-api-clean
+
+libServalDNA.a $(SWIFT_MODULE_NAME).swiftmodule $(SWIFT_MODULE_NAME).swiftdoc: swift-daemon-api
+	cp $(SWIFT_BUILD_DIR)/debug/$(notdir $@) $@
+
+swift-daemon-api:
+	mkdir -p $(SWIFT_BUILD_DIR) && \
+		cd $(SWIFT_PACKAGE_DIR) && \
+		$(SWIFT_BUILD) --build-path $(SWIFT_BUILD_DIR) $(SWIFT_BUILD_FLAGS) $(SWIFTDEFS)
+
+swift-daemon-api-clean:
+	$(RM) -r $(SWIFT_BUILD_DIR) \
+		 $(SWIFT_MODULE_NAME).swiftmodule \
+		 $(SWIFT_MODULE_NAME).swiftdoc
 
 swift-client-api:
 	@mkdir -p swift-client-api
@@ -369,12 +391,15 @@ ifneq ($(SWIFTC),) # Only provide Swift targets if the Swift compiler is availab
 # package.
 servaldswift: $(srcdir)/servaldswift.swift \
 	      $(OBJSDIR_SERVALD)/servald_features.o \
-	      $(OBJSDIR_SERVALD)/log_output_console.o \
 	      $(OBJSDIR_SERVALD)/log_output_file.o \
 	      libservaldaemon.a \
-	      $(srcdir)/module.modulemap
+	      $(SWIFT_MODULE_NAME).swiftmodule \
+	      libServalDNA.a
 	@echo SWIFT $@
-	@$(SWIFTC) -emit-executable $(SWIFTCFLAGS) $(SWIFTDEFS) -o $@ $(filter %.swift, $^) $(filter %.o, $^) $(filter %.a, $^) $(SWIFTLIBS)
+	@$(SWIFTC) -emit-executable -o $@ \
+		$(SWIFTCFLAGS) $(SWIFTDEFS) \
+		$(filter %.swift, $^) $(filter %.o, $^) $(filter %.a, $^) \
+		$(SWIFTLIBS)
 
 endif # $(SWIFTC)
 
@@ -413,7 +438,7 @@ libservalclient.a: _servalclient.a $(LIBSODIUM_A)
 
 libservalclient.so: $(LIB_SERVAL_OBJS) $(OBJSDIR_TOOLS)/version.o $(LIBSODIUM_A)
 	@echo LINK $@
-	@$(CC) -Wall -shared -o $@ $(LDFLAGS) $(filter %.o, $^) $(filter %.a, $^)
+	@$(CC) -Wall -shared -o $@ $(LDFLAGS) $(filter %.o %.a, $^) $(filter %.a, $^)
 
 .INTERMEDIATE: _monitorclient.a
 _monitorclient.a: $(MONITOR_CLIENT_OBJS) $(OBJSDIR_TOOLS)/version.o

cli_stdio.c

@@ -28,6 +28,10 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #include "log.h"
 #include "str.h"
 
+/* An instance of struct cli_vtable that prints all fields to a stdio stream.  This is used by the
+ * 'servald' daemon to print its output on stdout.
+ */
+
 static FILE *stdio_fp(struct cli_context *context)
 {
   return ((struct cli_context_stdio *)(context->context))->fp;

doc/Development.md

@@ -241,10 +241,10 @@ Serval DNA supports [Swift][], the language that Apple recommend for developing
 iOS apps for their mobile devices such as phones and tablets.  The
 `./configure` script [generated from configure.ac](#autotools) detects whether
 a [Swift 4][] compiler is present, or failing that, a [Swift 3][] compiler, and
-if so, then produces a Makefile that will compile
+if so, then produces a Makefile that will compile [servaldswift.swift][] into
-[servaldswift.swift](../servaldswift.swift) into the *servaldswift* executable,
+the *servaldswift* executable, to prove that the Swift [module
-to prove that the Swift [module map](../module.modulemap) allows Swift source
+map](../module.modulemap) allows Swift source code to invoke internal Serval
-code to invoke internal Serval DNA functions.
+DNA functions.
 
 The `./configure` script can be passed the following variables, either as
 environment variables or using the `VARNAME=value` syntax on its command line:
@@ -255,12 +255,45 @@ environment variables or using the `VARNAME=value` syntax on its command line:
 * `SWIFTCFLAGS` extra command-line arguments to pass to the Swift compiler;
   analogous to `CFLAGS` for the C compiler
 
+Swift Daemon API
+----------------
+
+Serval DNA provides a *Swift Daemon API* as a [Swift module][] called
+**ServalDNA**, which provides access to some of the internal APIs of the Serval
+DNA daemon by wrapping direct function invocations in Swift classes.
+
+The Swift daemon API is written as a set of [Swift][] "wrappers" around
+internal functions and constants that are declared in C header files.  Those
+internals are exposed to Swift by the Swift [module map](../module.modulemap),
+which defines a [Swift module][] called **servald** that has the following
+submodules:
+
+* **servald.log** the Serval DNA logging API, including the log output API
+
+* **servald.cli** the Serval DNA [CLI API][] and the daemon's command-line
+  entry point
+
+The [CliContext][] Swift class provides an object-oriented interface to the
+[CLI API][].  To capture the output from any CLI command, a Swift program can
+simply subclass [CliContext][] and override its `write()` method and any other
+methods as needed, then pass an instance of that subclass to the
+[serval\_commandline\_main][] function.  An example of how to do this is in
+[servaldswift.swift][], which uses an instance of the [CliContextFile][]
+subclass to print its output on standard output via a buffer.
+
+[servaldswift.swift][] shows how to capture Serval DNA log output in Swift
+code, by providing an implementation of the delegate log output `print()`
+function.  This works because [Makefile.in][] includes `log_output_delegate.o`
+in the link for the *servaldswift* executable, and omits the other log outputs.
+
 Swift Client API
 ----------------
 
 Serval DNA provides a *Swift Client API* as a [Swift module][] called
 **ServalClient**, which provides access to the services of the Serval DNA
-daemon through its [REST API][].
+daemon through its [REST API][].  Once an iOS app has started a thread that is
+running the daemon (invoked via the [Swift Daemon API](#swift-daemon-api)), the
+client API can be used to communicate with the running daemon thread.
 
 The Swift client API is written entirely in [Swift][] using the [URLSession][]
 Foundation class and related classes as the HTTP client.  The API is covered
@@ -307,10 +340,16 @@ Available under the [Creative Commons Attribution 4.0 International licence][CC
 [CC BY 4.0]: ../LICENSE-DOCUMENTATION.md
 [Serval DNA]: ../README.md
 [build]: ../INSTALL.md
+[CLI API]: ./CLI-API.md
 [REST API]: ./REST-API.md
 [Keyring REST API]: ./REST-API-Keyring.md
 [test scripts]: ./Testing.md
 [configure.ac]: ../configure.ac
+[Makefile.in]: ../Makefile.in
+[servaldswift.swift]: ../servaldswift.swift
+[CliContext]: ../swift-daemon-api/Sources/CliContext.swift
+[CliContextFile]: ../swift-daemon-api/Sources/CliContextFile.swift
+[serval\_commandline\_main]: ../swift-daemon-api/Sources/commandline.swift
 [autoconf]: http://www.gnu.org/software/autoconf/autoconf.html
 [autoconf macro archive]: http://www.gnu.org/software/autoconf-archive/
 [GNU M4]: http://www.gnu.org/software/m4/m4.html

jni_commandline.c

@@ -268,7 +268,8 @@ JNIEXPORT jint JNICALL Java_org_servalproject_servaldna_ServalDCommand_rawComman
   return (jint) status;
 }
 
-/* Output primitives for JNI.
+/* An instance of struct cli_vtable that passes all output fields to an IJniResults
+ * interface callback.
  */
 
 static struct jni_context *jni_context(struct cli_context *cli_context)

log_output_delegate.c

@@ -0,0 +1,134 @@
+/*
+Serval DNA logging output to a delegate
+Copyright 2017 Flinders University
+
+This program 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 program 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 program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#include "log.h"
+#include "log_output.h"
+#include "log_output_delegate.h"
+#include "strbuf.h"
+
+/* An implementation of the Serval logging API that constructs log messages in
+ * a buffer then passes the buffer to a delegate.
+ */
+
+/* Private state for delegate log output.
+ */
+
+struct log_output_delegate_state {
+  bool_t opened;
+  // Buffer to hold log messages before the log file is open and ready for writing:
+  struct strbuf	strbuf;
+  char buf[8192];
+};
+
+static struct log_output_delegate_state static_state = {
+  .opened = 0,
+  .strbuf = STRUCT_STRBUF_EMPTY,
+  .buf = ""
+};
+
+/* Functions for querying configuration.
+ */
+
+static int log_delegate_minimum_level(const struct log_output *UNUSED(out))
+{
+  return serval_log_delegate.minimum_level;
+}
+
+static bool_t log_delegate_show_pid(const struct log_output *UNUSED(out))
+{
+  return serval_log_delegate.show_pid;
+}
+
+static bool_t log_delegate_show_time(const struct log_output *UNUSED(out))
+{
+  return serval_log_delegate.show_time;
+}
+
+/* Log output operations.
+ */
+
+static inline struct log_output_delegate_state *_state(struct log_output *out)
+{
+  assert(out->state);
+  return (struct log_output_delegate_state *)(out->state);
+}
+
+static bool_t is_log_delegate_available(const struct log_output_iterator *UNUSED(it))
+{
+  return serval_log_delegate.print != NULL;
+}
+
+static void log_delegate_open(struct log_output_iterator *it)
+{
+  struct log_output_delegate_state *state = _state(*it->output);
+  if (!state->opened) {
+    state->opened = 1;
+    if (serval_log_delegate.show_prolog)
+      serval_log_print_prolog(it);
+  }
+}
+
+static void log_delegate_start_line(struct log_output_iterator *it, int UNUSED(level))
+{
+  struct log_output_delegate_state *state = _state(*it->output);
+  strbuf sb = &state->strbuf;
+  assert(strbuf_len(sb) == 0);
+  strbuf_init(sb, state->buf, sizeof state->buf);
+  it->xpf = XPRINTF_STRBUF(sb);
+}
+
+static void log_delegate_end_line(struct log_output_iterator *it, int level)
+{
+  struct log_output_delegate_state *state = _state(*it->output);
+  strbuf sb = &state->strbuf;
+  serval_log_delegate.print(level, strbuf_str(sb), strbuf_overrun(sb));
+  strbuf_reset(sb);
+}
+
+static void flush_log_delegate(struct log_output_iterator *UNUSED(it))
+{
+  if (serval_log_delegate.flush)
+    serval_log_delegate.flush();
+}
+
+static struct log_output static_log_output = {
+  .minimum_level = log_delegate_minimum_level,
+  .show_pid = log_delegate_show_pid,
+  .show_time = log_delegate_show_time,
+  .state = &static_state,
+  .open = log_delegate_open,
+  .capture_fd = NULL,
+  .is_available = is_log_delegate_available,
+  .start_line = log_delegate_start_line,
+  .end_line = log_delegate_end_line,
+  .flush = flush_log_delegate,
+  .close = NULL
+};
+
+DEFINE_LOG_OUTPUT(&static_log_output);
+
+// These are defaults only; the delegate fills this in as it wishes.
+struct log_delegate serval_log_delegate = {
+    .minimum_level = LOG_LEVEL_INFO,
+    .show_prolog = 1,
+    .show_pid = 0,
+    .show_time = 1,
+    .print = NULL,
+    .flush = NULL
+};

log_output_delegate.h

@@ -0,0 +1,36 @@
+/*
+Serval DNA logging output to a delegate
+Copyright (C) 2017 Flinders University
+ 
+This program 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 program 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 program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#ifndef __SERVAL_DNA__LOG_OUTPUT_DELEGATE_H
+#define __SERVAL_DNA__LOG_OUTPUT_DELEGATE_H
+
+#include "lang.h" // for bool_t
+
+struct log_delegate {
+    bool_t show_prolog;
+    int minimum_level;
+    bool_t show_pid;
+    bool_t show_time;
+    void (*print)(int level, const char *message, bool_t overrun);
+    void (*flush)();
+};
+
+extern struct log_delegate serval_log_delegate;
+
+#endif // __SERVAL_DNA__LOG_OUTPUT_DELEGATE_H

module.modulemap

@@ -1,5 +1,5 @@
 /*
-Serval DNA module map 
+Serval DNA Swift module map
 Copyright (C) 2016-2017 Flinders University
 
 This program is free software; you can redistribute it and/or
@@ -21,7 +21,14 @@ module servald {
 
     requires tls // thread-local storage
 
-    module main {
+    module cli {
-        header "servald_main.h"
+        header "commandline.h"
+        header "cli.h"
+    }
+
+    module log {
+        header "log.h"
+        header "log_output.h"
+        header "log_output_delegate.h"
     }
 }

servaldswift.swift

@@ -1,14 +1,54 @@
+/*
+Serval DNA daemon in Swift
+Copyright 2017 Flinders University
+
+This program 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 program 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 program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
 import Foundation
-import servald.main
+import ServalDNA
+import servald.log
 
-public func serval_daemon_main(args: [String]) -> CInt {
+// Logging
-    // print "args = \(args)"
+//
-    var argv = args.map { strdup($0) }
+// A simplistic console log outputter that writes to standard error and is not
-    argv.append(nil)
+// configurable.  Note that log_output_console.o is not linked into
-    defer {
+// servaldswift, in order to avoid duplicate log outputs on standard error.
-        argv.forEach { free($0) }
+
-    }
+private func logPrint(_ level: CInt, _ message: UnsafePointer<CChar>?, _ overrun: Int8) {
-    return servald_main(CInt(argv.count - 1), &argv)
+    let level_text = String(cString: serval_log_level_prefix_string(level)!)
+    let message_text = String(cString: message!)
+    FileHandle.standardError.write("\(level_text) \(message_text)\n".data(using:.utf8)!)
 }
 
-exit(serval_daemon_main(args: CommandLine.arguments))
+serval_log_delegate.print = logPrint
+serval_log_delegate.minimum_level = LOG_LEVEL_WARN
+serval_log_delegate.show_prolog = 1
+serval_log_delegate.show_pid = 1
+serval_log_delegate.show_time = 1
+
+// Output
+
+var contextFile = CliContextFile(FileHandle.standardOutput)
+
+// Invocation
+
+let status = serval_commandline_main(context: contextFile, args: CommandLine.arguments)
+
+// Cleanup
+
+contextFile.flush()
+
+exit(status)

sourcefiles.mk

@@ -62,6 +62,7 @@ SERVAL_DAEMON_SOURCES = \
 	keyring_restful.c \
 	log_output_console.c \
 	log_output_file.c \
+	log_output_delegate.c \
 	lsif.c \
 	radio_link.c \
 	meshms.c \
@@ -131,6 +132,12 @@ SERVAL_DAEMON_JNI_SOURCES = \
 	jni_instance.c \
 	jni_server.c
 
+SERVAL_DAEMON_SWIFT_SOURCES = \
+	swift_main.swift \
+	swift_cli.swift \
+	swift_cli_stdio.swift \
+	swift_log.swift
+
 MDP_CLIENT_SOURCES = \
 	mdp_client.c
 

swift-client-api/Makefile.in

@@ -23,16 +23,18 @@ SWIFT_BUILD_FLAGS= 	$(addprefix -Xswiftc , $(SWIFTCFLAGS))
 DEFS=			@DEFS@
 SWIFTDEFS=		$(addprefix -Xcc , $(DEFS))
 
-.PHONY: all check check_swiftc check_swift_build swiftmodule clean
+.PHONY: all
-
+all:	check package swift-client-util
-all:	check swiftmodule swift-client-util
 
+.PHONY: check
 check:	check_swiftc check_swift_build
 
+.PHONY: check_swiftc
 check_swiftc:
 	@if [ -z "$(SWIFTC)" ]; then echo "No swift compiler configured" >&2; exit 1; fi
 	@if ! $(SWIFTC) -version >/dev/null; then echo "Swift compiler not executable" >&2; exit 1; fi
 
+.PHONY: check_swift_build
 check_swift_build:
 	@if [ -z "$(SWIFT_BUILD)" ]; then echo "No swift package manager configured" >&2; exit 1; fi
 	@if ! $(SWIFT_BUILD) -h >/dev/null; then echo "Swift package manager not executable" >&2; exit 1; fi
@@ -40,17 +42,19 @@ check_swift_build:
 # The Swift 3 package manager --chdir option was replaced with --package-path
 # in Swift 4, so to support both, avoid the options altogether and use "cd
 # package-dir && swift build" instead.
-swiftmodule:
+.PHONY: package
+package:
 	mkdir -p $(SWIFT_BUILD_DIR) && \
 		cd $(SWIFT_PACKAGE_DIR) && \
 		$(SWIFT_BUILD) --build-path $(SWIFT_BUILD_DIR) $(SWIFT_BUILD_FLAGS) $(SWIFTDEFS)
 
-$(SWIFT_BUILD_DIR)/debug/libServalClient.a: swiftmodule
+$(SWIFT_BUILD_DIR)/debug/libServalClient.a: package
 
 swift-client-util: $(srcdir)/client_util.swift $(SWIFT_BUILD_DIR)/debug/libServalClient.a
 	@echo SWIFT $@
 	@$(SWIFTC) -emit-executable $(SWIFTCFLAGS) $(SWIFTDEFS) -I $(SWIFT_BUILD_DIR)/debug -o $@ $^
 
+.PHONY: clean
 clean:
 	$(RM) -r $(SWIFT_BUILD_DIR)
 	$(RM) swift-client-util

swift-daemon-api/Package.swift

@@ -0,0 +1,9 @@
+import PackageDescription
+
+let package = Package(
+        name: "ServalDNA"
+    )
+
+products.append(
+        Product(name: "ServalDNA", type: .Library(.Static), modules: "ServalDNA")
+    )

swift-daemon-api/Sources/CliContext.swift

@@ -0,0 +1,158 @@
+/*
+Serval DNA Swift CLI output
+Copyright 2017 Flinders University
+
+This program 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 program 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 program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+import Foundation
+import servald.cli
+
+private extension Data {
+    var hexUpper: String {
+        return map { String(format: "%02hhX", $0) }.joined()
+    }
+}
+
+open class CliContext {
+    public var cContext: cli_context = cli_context(context: nil, vtable: nil)
+
+    public init() {
+        cContext.context = UnsafeMutableRawPointer(Unmanaged.passUnretained(self).toOpaque())
+        cContext.vtable = UnsafeMutablePointer<cli_vtable>(&cliVtable)
+    }
+
+    // Subclasses override these as needed:
+
+    func delim(_ opt: String? = nil) {}
+
+    func write(_ data: Data) {}
+
+    func puts(_ str: String) {
+        self.write(str.data(using:.utf8)!)
+    }
+
+    func flush() {}
+
+    func putString(_ str: String, _ delim: String? = nil) {
+        self.puts(str)
+        self.delim(delim)
+    }
+
+    func putLong(_ value: Int64, _ delim: String? = nil) {
+        self.puts("\(value)")
+        self.delim(delim)
+    }
+
+    func putHexData(_ data: Data, _ delim: String? = nil) {
+        self.puts(data.hexUpper)
+        self.delim(delim)
+    }
+
+    func putBlob(_ data: Data, _ delim: String? = nil) {
+        self.write(data)
+        self.delim(delim)
+    }
+
+    func startTable(column_names: [String]) {
+        self.putLong(Int64(column_names.count))
+        for i in 0 ..< column_names.count {
+            self.putString(column_names[i], i == column_names.count - 1 ? nil : ":")
+        }
+    }
+
+    func endTable(row_count: Int) {}
+
+    func fieldName(_ name: String, _ delim: String? = nil) {
+        self.putString(name)
+        self.delim(delim)
+    }
+}
+
+private func _self(_ context: UnsafeMutablePointer<cli_context>?) -> CliContext {
+    return Unmanaged<CliContext>.fromOpaque(context!.pointee.context).takeUnretainedValue()
+}
+
+private func cliDelim(_ context: UnsafeMutablePointer<cli_context>?, _ opt: UnsafePointer<CChar>?) -> Void {
+    _self(context).delim(opt != nil ? String(cString: opt!) : nil)
+}
+
+private func cliWrite(_ context: UnsafeMutablePointer<cli_context>?, _ buf: UnsafePointer<CChar>?, _ len: Int) -> Void {
+    if buf != nil {
+        _self(context).write(Data(bytes: buf!, count: len))
+    }
+}
+
+private func cliPuts(_ context: UnsafeMutablePointer<cli_context>?, _ str: UnsafePointer<CChar>?) -> Void {
+    if str != nil {
+        _self(context).putString(String(cString: str!))
+    }
+}
+
+private func cliVprintf(_ context: UnsafeMutablePointer<cli_context>?, _ fmt: UnsafePointer<CChar>?, _ ap: CVaListPointer) -> Void {
+    let str = NSString(format: String(cString: fmt!), arguments: ap)
+    _self(context).putString(String(data: str.data(using: String.Encoding.utf16.rawValue)!, encoding:.utf16)!)
+}
+
+private func cliPutLong(_ context: UnsafeMutablePointer<cli_context>?, _ value: Int64, _ delim: UnsafePointer<CChar>?) -> Void {
+    _self(context).putLong(value, delim != nil ? String(cString: delim!) : nil)
+}
+
+private func cliPutString(_ context: UnsafeMutablePointer<cli_context>?, _ value: UnsafePointer<CChar>?, _ delim: UnsafePointer<CChar>?) -> Void {
+    _self(context).putString(value != nil ? String(cString: value!) : "",
+                             delim != nil ? String(cString: delim!) : nil)
+}
+
+private func cliPutHexvalue(_ context: UnsafeMutablePointer<cli_context>?, _ buf: UnsafePointer<CUnsignedChar>?, _ len: Int, _ delim: UnsafePointer<CChar>?) -> Void {
+    _self(context).putHexData(buf != nil ? Data(bytes: buf!, count: len) : Data(),
+                              delim != nil ? String(cString: delim!) : nil)
+}
+
+private func cliPutBlob(_ context: UnsafeMutablePointer<cli_context>?, _ blob: UnsafePointer<CUnsignedChar>?, _ len: Int, _ delim: UnsafePointer<CChar>?) -> Void {
+    _self(context).putBlob(blob != nil ? Data(bytes: UnsafeRawPointer(blob!).bindMemory(to: CChar.self, capacity: len), count: len) : Data(),
+                           delim != nil ? String(cString: delim!) : nil)
+}
+
+private func cliStartTable(_ context: UnsafeMutablePointer<cli_context>?, _ column_count: Int, _ column_names: UnsafeMutablePointer<UnsafePointer<CChar>?>?) -> Void {
+    let names = (0..<column_count).map { String(cString: column_names![$0]!) }
+    _self(context).startTable(column_names: names)
+}
+
+private func cliEndTable(_ context: UnsafeMutablePointer<cli_context>?, _ row_count: Int) -> Void {
+    _self(context).endTable(row_count: row_count)
+}
+
+private func cliFieldName(_ context: UnsafeMutablePointer<cli_context>?, _ name: UnsafePointer<CChar>?, _ delim: UnsafePointer<CChar>?) -> Void {
+    _self(context).fieldName(name != nil ? String(cString: name!) : "", delim != nil ? String(cString: delim!) : nil)
+}
+
+private func cliFlush(_ context: UnsafeMutablePointer<cli_context>?) -> Void {
+    _self(context).flush()
+}
+
+private var cliVtable = cli_vtable(
+        delim: cliDelim,
+        write: cliWrite,
+        puts: cliPuts,
+        vprintf: cliVprintf,
+        put_long: cliPutLong,
+        put_string: cliPutString,
+        put_hexvalue: cliPutHexvalue,
+        put_blob: cliPutBlob,
+        start_table: cliStartTable,
+        end_table: cliEndTable,
+        field_name: cliFieldName,
+        flush: cliFlush
+    )

swift-daemon-api/Sources/CliContextFile.swift

@@ -0,0 +1,54 @@
+/*
+Serval DNA Swift CLI output to stdio stream
+Copyright 2017 Flinders University
+
+This program 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 program 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 program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+import Foundation
+
+/* An instance of struct cli_vtable that prints all fields to a stdio stream
+ * via a buffer.  This is the Swift equivalent of cli_stdio.c.  It is used by
+ * the 'servaldswift' daemon to produce its output.
+ */
+
+open class CliContextFile: CliContext {
+    private var fileHandle: FileHandle
+    private var buffer: Data
+    private let bufsize: Int? = nil
+
+    public init(_ file: FileHandle) {
+        self.fileHandle = file
+        self.buffer = Data()
+    }
+
+    public override func delim(_ opt: String?) {
+        self.puts(ProcessInfo.processInfo.environment["SERVALD_OUTPUT_DELIMITER"] ?? opt ?? "\n")
+    }
+
+    public override func write(_ data: Data) {
+        self.buffer.append(data)
+        if self.bufsize != nil && self.buffer.count >= self.bufsize! {
+            self.flush()
+        }
+    }
+
+    public override func flush() {
+        if !self.buffer.isEmpty {
+            self.fileHandle.write(self.buffer)
+            self.buffer.removeAll()
+        }
+    }
+}

swift-daemon-api/Sources/commandline.swift

@@ -0,0 +1,39 @@
+/*
+Serval DNA Swift command-line entry point
+Copyright 2017 Flinders University
+
+This program 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 program 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 program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+import Foundation
+import servald.cli
+
+/* A Swift entry point to the Serval DNA daemon command-line entry point, which takes a
+ * [String] parameter, converts it into an argv array of C strings, and invokes
+ * the C main entry point with argv0, and argc/argv arguments.
+ */
+public func serval_commandline_main(context: CliContext, args: [String]) -> CInt {
+    var margv = args.map { strdup($0) }
+    margv.append(nil)
+    defer {
+        margv.forEach { free($0) }
+    }
+    let argv0 = margv[0]
+    margv.remove(at: 0)
+    let argv = margv.map { $0 != nil ? UnsafePointer<CChar>?($0!) : nil }
+    return argv.withUnsafeBufferPointer {
+        return commandline_main(&context.cContext, argv0, CInt(argv.count - 1), $0.baseAddress!)
+    }
+}

swift-daemon-api/Sources/log.swift

@@ -0,0 +1,39 @@
+import servald.log
+
+private func serval_log(level: CInt, format: String, va_list: CVaListPointer) {
+    format.withCString { CString in
+        serval_vlogf(level, __whence, CString, va_list)
+    }
+}
+
+public func serval_log(level: CInt, text: String) {
+    text.withCString { CString in
+        withVaList([CString]) { va_list in
+            serval_log(level: level, format: "%s", va_list: va_list)
+        }
+    }
+}
+
+public func serval_log_fatal(_ text: String) {
+    serval_log(level: LOG_LEVEL_FATAL, text: text)
+}
+
+public func serval_log_error(_ text: String) {
+    serval_log(level: LOG_LEVEL_ERROR, text: text)
+}
+
+public func serval_log_warning(_ text: String) {
+    serval_log(level: LOG_LEVEL_WARN, text: text)
+}
+
+public func serval_log_hint(_ text: String) {
+    serval_log(level: LOG_LEVEL_HINT, text: text)
+}
+
+public func serval_log_info(_ text: String) {
+    serval_log(level: LOG_LEVEL_INFO, text: text)
+}
+
+public func serval_log_debug(_ text: String) {
+    serval_log(level: LOG_LEVEL_DEBUG, text: text)
+}