Source file src/pkg/cmd/internal/obj/stringer.go

     1	// Copyright 2015 The Go Authors. All rights reserved.
     2	// Use of this source code is governed by a BSD-style
     3	// license that can be found in the LICENSE file.
     4	
     5	// +build ignore
     6	
     7	// This is a mini version of the stringer tool customized for the Anames table
     8	// in the architecture support for obj.
     9	// This version just generates the slice of strings, not the String method.
    10	
    11	package main
    12	
    13	import (
    14		"bufio"
    15		"flag"
    16		"fmt"
    17		"log"
    18		"os"
    19		"regexp"
    20		"strings"
    21	)
    22	
    23	var (
    24		input  = flag.String("i", "", "input file name")
    25		output = flag.String("o", "", "output file name")
    26		pkg    = flag.String("p", "", "package name")
    27	)
    28	
    29	var Are = regexp.MustCompile(`^\tA([A-Za-z0-9]+)`)
    30	
    31	func main() {
    32		flag.Parse()
    33		if *input == "" || *output == "" || *pkg == "" {
    34			flag.Usage()
    35			os.Exit(2)
    36		}
    37		in, err := os.Open(*input)
    38		if err != nil {
    39			log.Fatal(err)
    40		}
    41		fd, err := os.Create(*output)
    42		if err != nil {
    43			log.Fatal(err)
    44		}
    45		out := bufio.NewWriter(fd)
    46		defer out.Flush()
    47		var on = false
    48		s := bufio.NewScanner(in)
    49		first := true
    50		for s.Scan() {
    51			line := s.Text()
    52			if !on {
    53				// First relevant line contains "= obj.ABase".
    54				// If we find it, delete the = so we don't stop immediately.
    55				const prefix = "= obj.ABase"
    56				index := strings.Index(line, prefix)
    57				if index < 0 {
    58					continue
    59				}
    60				// It's on. Start with the header.
    61				fmt.Fprintf(out, header, *input, *output, *pkg, *pkg)
    62				on = true
    63				line = line[:index]
    64			}
    65			// Strip comments so their text won't defeat our heuristic.
    66			index := strings.Index(line, "//")
    67			if index > 0 {
    68				line = line[:index]
    69			}
    70			index = strings.Index(line, "/*")
    71			if index > 0 {
    72				line = line[:index]
    73			}
    74			// Termination condition: Any line with an = changes the sequence,
    75			// so stop there, and stop at a closing brace.
    76			if strings.HasPrefix(line, "}") || strings.ContainsRune(line, '=') {
    77				break
    78			}
    79			sub := Are.FindStringSubmatch(line)
    80			if len(sub) < 2 {
    81				continue
    82			}
    83			if first {
    84				fmt.Fprintf(out, "\tobj.A_ARCHSPECIFIC: %q,\n", sub[1])
    85				first = false
    86			} else {
    87				fmt.Fprintf(out, "\t%q,\n", sub[1])
    88			}
    89		}
    90		fmt.Fprintln(out, "}")
    91		if s.Err() != nil {
    92			log.Fatal(err)
    93		}
    94	}
    95	
    96	const header = `// Code generated by stringer -i %s -o %s -p %s; DO NOT EDIT.
    97	
    98	package %s
    99	
   100	import "cmd/internal/obj"
   101	
   102	var Anames = []string{
   103	`
   104	

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