build: separate compiler and libs

compiler/cmd/internal/base/base.go

@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2023 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// Package base defines shared basic pieces of the llgo command,
+// in particular logging and the Command structure.
+package base
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+)
+
+// A Command is an implementation of a gop command
+// like gop export or gop install.
+type Command struct {
+	// Run runs the command.
+	// The args are the arguments after the command name.
+	Run func(cmd *Command, args []string)
+
+	// UsageLine is the one-line usage message.
+	// The words between "gop" and the first flag or argument in the line are taken to be the command name.
+	UsageLine string
+
+	// Short is the short description shown in the 'gop help' output.
+	Short string
+
+	// Flag is a set of flags specific to this command.
+	Flag flag.FlagSet
+
+	// Commands lists the available commands and help topics.
+	// The order here is the order in which they are printed by 'gop help'.
+	// Note that subcommands are in general best avoided.
+	Commands []*Command
+}
+
+// Llgo command
+var Llgo = &Command{
+	UsageLine: "llgo",
+	Short:     `llgo is a Go compiler based on LLVM in order to better integrate Go with the C ecosystem including Python.`,
+	// Commands initialized in package main
+}
+
+// LongName returns the command's long name: all the words in the usage line between "gop" and a flag or argument,
+func (c *Command) LongName() string {
+	name := c.UsageLine
+	if i := strings.Index(name, " ["); i >= 0 {
+		name = name[:i]
+	}
+	if name == "llgo" {
+		return ""
+	}
+	return strings.TrimPrefix(name, "llgo ")
+}
+
+// Name returns the command's short name: the last word in the usage line before a flag or argument.
+func (c *Command) Name() string {
+	name := c.LongName()
+	if i := strings.LastIndex(name, " "); i >= 0 {
+		name = name[i+1:]
+	}
+	return name
+}
+
+// Usage show the command usage.
+func (c *Command) Usage(w io.Writer) {
+	fmt.Fprintf(w, "%s\n\nUsage: %s\n", c.Short, c.UsageLine)
+
+	// restore output of flag
+	defer c.Flag.SetOutput(c.Flag.Output())
+
+	c.Flag.SetOutput(w)
+	c.Flag.PrintDefaults()
+	fmt.Fprintln(w)
+	os.Exit(2)
+}
+
+// Runnable reports whether the command can be run; otherwise
+// it is a documentation pseudo-command.
+func (c *Command) Runnable() bool {
+	return c.Run != nil
+}
+
+// Usage is the usage-reporting function, filled in by package main
+// but here for reference by other packages.
+//
+// flag.Usage func()
+
+// CmdName - "build", "install", "list", "mod tidy", etc.
+var CmdName string
+
+// Main runs a command.
+func Main(c *Command, app string, args []string) {
+	name := c.UsageLine
+	if i := strings.Index(name, " ["); i >= 0 {
+		c.UsageLine = app + name[i:]
+	}
+	c.Run(c, args)
+}