github.com/xingly-cn/shorturl-go@v0.0.0-20220110130535-e21de4659f74/pkg/mod/golang.org/x/sys@v0.0.0-20200323222414-85ca7c5b95cd/unix/mkasm_darwin.go (about)

     1  // Copyright 2018 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  // mkasm_darwin.go generates assembly trampolines to call libSystem routines from Go.
     8  //This program must be run after mksyscall.go.
     9  package main
    10  
    11  import (
    12  	"bytes"
    13  	"fmt"
    14  	"io/ioutil"
    15  	"log"
    16  	"os"
    17  	"strings"
    18  )
    19  
    20  func writeASMFile(in string, fileName string, buildTags string) {
    21  	trampolines := map[string]bool{}
    22  
    23  	var out bytes.Buffer
    24  
    25  	fmt.Fprintf(&out, "// go run mkasm_darwin.go %s\n", strings.Join(os.Args[1:], " "))
    26  	fmt.Fprintf(&out, "// Code generated by the command above; DO NOT EDIT.\n")
    27  	fmt.Fprintf(&out, "\n")
    28  	fmt.Fprintf(&out, "// +build %s\n", buildTags)
    29  	fmt.Fprintf(&out, "\n")
    30  	fmt.Fprintf(&out, "#include \"textflag.h\"\n")
    31  	for _, line := range strings.Split(in, "\n") {
    32  		if !strings.HasPrefix(line, "func ") || !strings.HasSuffix(line, "_trampoline()") {
    33  			continue
    34  		}
    35  		fn := line[5 : len(line)-13]
    36  		if !trampolines[fn] {
    37  			trampolines[fn] = true
    38  			fmt.Fprintf(&out, "TEXT ยท%s_trampoline(SB),NOSPLIT,$0-0\n", fn)
    39  			fmt.Fprintf(&out, "\tJMP\t%s(SB)\n", fn)
    40  		}
    41  	}
    42  	err := ioutil.WriteFile(fileName, out.Bytes(), 0644)
    43  	if err != nil {
    44  		log.Fatalf("can't write %s: %s", fileName, err)
    45  	}
    46  }
    47  
    48  func main() {
    49  	in1, err := ioutil.ReadFile("syscall_darwin.go")
    50  	if err != nil {
    51  		log.Fatalf("can't open syscall_darwin.go: %s", err)
    52  	}
    53  	arch := os.Args[1]
    54  	in2, err := ioutil.ReadFile(fmt.Sprintf("syscall_darwin_%s.go", arch))
    55  	if err != nil {
    56  		log.Fatalf("can't open syscall_darwin_%s.go: %s", arch, err)
    57  	}
    58  	in3, err := ioutil.ReadFile(fmt.Sprintf("zsyscall_darwin_%s.go", arch))
    59  	if err != nil {
    60  		log.Fatalf("can't open zsyscall_darwin_%s.go: %s", arch, err)
    61  	}
    62  	in := string(in1) + string(in2) + string(in3)
    63  
    64  	writeASMFile(in, fmt.Sprintf("zsyscall_darwin_%s.s", arch), "go1.12")
    65  
    66  	in1, err = ioutil.ReadFile("syscall_darwin.1_13.go")
    67  	if err != nil {
    68  		log.Fatalf("can't open syscall_darwin.1_13.go: %s", err)
    69  	}
    70  	in2, err = ioutil.ReadFile(fmt.Sprintf("zsyscall_darwin_%s.1_13.go", arch))
    71  	if err != nil {
    72  		log.Fatalf("can't open zsyscall_darwin_%s.1_13.go: %s", arch, err)
    73  	}
    74  
    75  	in = string(in1) + string(in2)
    76  
    77  	writeASMFile(in, fmt.Sprintf("zsyscall_darwin_%s.1_13.s", arch), "go1.13")
    78  }