cmd/bpa-operator/vendor/golang.org/x/sys/unix/mksyscall_solaris.go

   1 // Copyright 2019 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 /*
   8  This program reads a file containing function prototypes
   9  (like syscall_solaris.go) and generates system call bodies.
  10  The prototypes are marked by lines beginning with "//sys"
  11  and read like func declarations if //sys is replaced by func, but:
  12         * The parameter lists must give a name for each argument.
  13           This includes return parameters.
  14         * The parameter lists must give a type for each argument:
  15           the (x, y, z int) shorthand is not allowed.
  16         * If the return parameter is an error number, it must be named err.
  17         * If go func name needs to be different than its libc name,
  18         * or the function is not in libc, name could be specified
  19         * at the end, after "=" sign, like
  20           //sys getsockopt(s int, level int, name int, val uintptr, vallen *_Socklen) (err error) = libsocket.getsockopt
  21 */
  22
  23 package main
  24
  25 import (
  26         "bufio"
  27         "flag"
  28         "fmt"
  29         "os"
  30         "regexp"
  31         "strings"
  32 )
  33
  34 var (
  35         b32  = flag.Bool("b32", false, "32bit big-endian")
  36         l32  = flag.Bool("l32", false, "32bit little-endian")
  37         tags = flag.String("tags", "", "build tags")
  38 )
  39
  40 // cmdLine returns this programs's commandline arguments
  41 func cmdLine() string {
  42         return "go run mksyscall_solaris.go " + strings.Join(os.Args[1:], " ")
  43 }
  44
  45 // buildTags returns build tags
  46 func buildTags() string {
  47         return *tags
  48 }
  49
  50 // Param is function parameter
  51 type Param struct {
  52         Name string
  53         Type string
  54 }
  55
  56 // usage prints the program usage
  57 func usage() {
  58         fmt.Fprintf(os.Stderr, "usage: go run mksyscall_solaris.go [-b32 | -l32] [-tags x,y] [file ...]\n")
  59         os.Exit(1)
  60 }
  61
  62 // parseParamList parses parameter list and returns a slice of parameters
  63 func parseParamList(list string) []string {
  64         list = strings.TrimSpace(list)
  65         if list == "" {
  66                 return []string{}
  67         }
  68         return regexp.MustCompile(`\s*,\s*`).Split(list, -1)
  69 }
  70
  71 // parseParam splits a parameter into name and type
  72 func parseParam(p string) Param {
  73         ps := regexp.MustCompile(`^(\S*) (\S*)$`).FindStringSubmatch(p)
  74         if ps == nil {
  75                 fmt.Fprintf(os.Stderr, "malformed parameter: %s\n", p)
  76                 os.Exit(1)
  77         }
  78         return Param{ps[1], ps[2]}
  79 }
  80
  81 func main() {
  82         flag.Usage = usage
  83         flag.Parse()
  84         if len(flag.Args()) <= 0 {
  85                 fmt.Fprintf(os.Stderr, "no files to parse provided\n")
  86                 usage()
  87         }
  88
  89         endianness := ""
  90         if *b32 {
  91                 endianness = "big-endian"
  92         } else if *l32 {
  93                 endianness = "little-endian"
  94         }
  95
  96         pack := ""
  97         text := ""
  98         dynimports := ""
  99         linknames := ""
 100         var vars []string
 101         for _, path := range flag.Args() {
 102                 file, err := os.Open(path)
 103                 if err != nil {
 104                         fmt.Fprintf(os.Stderr, err.Error())
 105                         os.Exit(1)
 106                 }
 107                 s := bufio.NewScanner(file)
 108                 for s.Scan() {
 109                         t := s.Text()
 110                         t = strings.TrimSpace(t)
 111                         t = regexp.MustCompile(`\s+`).ReplaceAllString(t, ` `)
 112                         if p := regexp.MustCompile(`^package (\S+)$`).FindStringSubmatch(t); p != nil && pack == "" {
 113                                 pack = p[1]
 114                         }
 115                         nonblock := regexp.MustCompile(`^\/\/sysnb `).FindStringSubmatch(t)
 116                         if regexp.MustCompile(`^\/\/sys `).FindStringSubmatch(t) == nil && nonblock == nil {
 117                                 continue
 118                         }
 119
 120                         // Line must be of the form
 121                         //      func Open(path string, mode int, perm int) (fd int, err error)
 122                         // Split into name, in params, out params.
 123                         f := regexp.MustCompile(`^\/\/sys(nb)? (\w+)\(([^()]*)\)\s*(?:\(([^()]+)\))?\s*(?:=\s*(?:(\w*)\.)?(\w*))?$`).FindStringSubmatch(t)
 124                         if f == nil {
 125                                 fmt.Fprintf(os.Stderr, "%s:%s\nmalformed //sys declaration\n", path, t)
 126                                 os.Exit(1)
 127                         }
 128                         funct, inps, outps, modname, sysname := f[2], f[3], f[4], f[5], f[6]
 129
 130                         // Split argument lists on comma.
 131                         in := parseParamList(inps)
 132                         out := parseParamList(outps)
 133
 134                         inps = strings.Join(in, ", ")
 135                         outps = strings.Join(out, ", ")
 136
 137                         // Try in vain to keep people from editing this file.
 138                         // The theory is that they jump into the middle of the file
 139                         // without reading the header.
 140                         text += "// THIS FILE IS GENERATED BY THE COMMAND AT THE TOP; DO NOT EDIT\n\n"
 141
 142                         // So file name.
 143                         if modname == "" {
 144                                 modname = "libc"
 145                         }
 146
 147                         // System call name.
 148                         if sysname == "" {
 149                                 sysname = funct
 150                         }
 151
 152                         // System call pointer variable name.
 153                         sysvarname := fmt.Sprintf("proc%s", sysname)
 154
 155                         strconvfunc := "BytePtrFromString"
 156                         strconvtype := "*byte"
 157
 158                         sysname = strings.ToLower(sysname) // All libc functions are lowercase.
 159
 160                         // Runtime import of function to allow cross-platform builds.
 161                         dynimports += fmt.Sprintf("//go:cgo_import_dynamic libc_%s %s \"%s.so\"\n", sysname, sysname, modname)
 162                         // Link symbol to proc address variable.
 163                         linknames += fmt.Sprintf("//go:linkname %s libc_%s\n", sysvarname, sysname)
 164                         // Library proc address variable.
 165                         vars = append(vars, sysvarname)
 166
 167                         // Go function header.
 168                         outlist := strings.Join(out, ", ")
 169                         if outlist != "" {
 170                                 outlist = fmt.Sprintf(" (%s)", outlist)
 171                         }
 172                         if text != "" {
 173                                 text += "\n"
 174                         }
 175                         text += fmt.Sprintf("func %s(%s)%s {\n", funct, strings.Join(in, ", "), outlist)
 176
 177                         // Check if err return available
 178                         errvar := ""
 179                         for _, param := range out {
 180                                 p := parseParam(param)
 181                                 if p.Type == "error" {
 182                                         errvar = p.Name
 183                                         continue
 184                                 }
 185                         }
 186
 187                         // Prepare arguments to Syscall.
 188                         var args []string
 189                         n := 0
 190                         for _, param := range in {
 191                                 p := parseParam(param)
 192                                 if regexp.MustCompile(`^\*`).FindStringSubmatch(p.Type) != nil {
 193                                         args = append(args, "uintptr(unsafe.Pointer("+p.Name+"))")
 194                                 } else if p.Type == "string" && errvar != "" {
 195                                         text += fmt.Sprintf("\tvar _p%d %s\n", n, strconvtype)
 196                                         text += fmt.Sprintf("\t_p%d, %s = %s(%s)\n", n, errvar, strconvfunc, p.Name)
 197                                         text += fmt.Sprintf("\tif %s != nil {\n\t\treturn\n\t}\n", errvar)
 198                                         args = append(args, fmt.Sprintf("uintptr(unsafe.Pointer(_p%d))", n))
 199                                         n++
 200                                 } else if p.Type == "string" {
 201                                         fmt.Fprintf(os.Stderr, path+":"+funct+" uses string arguments, but has no error return\n")
 202                                         text += fmt.Sprintf("\tvar _p%d %s\n", n, strconvtype)
 203                                         text += fmt.Sprintf("\t_p%d, _ = %s(%s)\n", n, strconvfunc, p.Name)
 204                                         args = append(args, fmt.Sprintf("uintptr(unsafe.Pointer(_p%d))", n))
 205                                         n++
 206                                 } else if s := regexp.MustCompile(`^\[\](.*)`).FindStringSubmatch(p.Type); s != nil {
 207                                         // Convert slice into pointer, length.
 208                                         // Have to be careful not to take address of &a[0] if len == 0:
 209                                         // pass nil in that case.
 210                                         text += fmt.Sprintf("\tvar _p%d *%s\n", n, s[1])
 211                                         text += fmt.Sprintf("\tif len(%s) > 0 {\n\t\t_p%d = &%s[0]\n\t}\n", p.Name, n, p.Name)
 212                                         args = append(args, fmt.Sprintf("uintptr(unsafe.Pointer(_p%d))", n), fmt.Sprintf("uintptr(len(%s))", p.Name))
 213                                         n++
 214                                 } else if p.Type == "int64" && endianness != "" {
 215                                         if endianness == "big-endian" {
 216                                                 args = append(args, fmt.Sprintf("uintptr(%s>>32)", p.Name), fmt.Sprintf("uintptr(%s)", p.Name))
 217                                         } else {
 218                                                 args = append(args, fmt.Sprintf("uintptr(%s)", p.Name), fmt.Sprintf("uintptr(%s>>32)", p.Name))
 219                                         }
 220                                 } else if p.Type == "bool" {
 221                                         text += fmt.Sprintf("\tvar _p%d uint32\n", n)
 222                                         text += fmt.Sprintf("\tif %s {\n\t\t_p%d = 1\n\t} else {\n\t\t_p%d = 0\n\t}\n", p.Name, n, n)
 223                                         args = append(args, fmt.Sprintf("uintptr(_p%d)", n))
 224                                         n++
 225                                 } else {
 226                                         args = append(args, fmt.Sprintf("uintptr(%s)", p.Name))
 227                                 }
 228                         }
 229                         nargs := len(args)
 230
 231                         // Determine which form to use; pad args with zeros.
 232                         asm := "sysvicall6"
 233                         if nonblock != nil {
 234                                 asm = "rawSysvicall6"
 235                         }
 236                         if len(args) <= 6 {
 237                                 for len(args) < 6 {
 238                                         args = append(args, "0")
 239                                 }
 240                         } else {
 241                                 fmt.Fprintf(os.Stderr, "%s: too many arguments to system call\n", path)
 242                                 os.Exit(1)
 243                         }
 244
 245                         // Actual call.
 246                         arglist := strings.Join(args, ", ")
 247                         call := fmt.Sprintf("%s(uintptr(unsafe.Pointer(&%s)), %d, %s)", asm, sysvarname, nargs, arglist)
 248
 249                         // Assign return values.
 250                         body := ""
 251                         ret := []string{"_", "_", "_"}
 252                         doErrno := false
 253                         for i := 0; i < len(out); i++ {
 254                                 p := parseParam(out[i])
 255                                 reg := ""
 256                                 if p.Name == "err" {
 257                                         reg = "e1"
 258                                         ret[2] = reg
 259                                         doErrno = true
 260                                 } else {
 261                                         reg = fmt.Sprintf("r%d", i)
 262                                         ret[i] = reg
 263                                 }
 264                                 if p.Type == "bool" {
 265                                         reg = fmt.Sprintf("%d != 0", reg)
 266                                 }
 267                                 if p.Type == "int64" && endianness != "" {
 268                                         // 64-bit number in r1:r0 or r0:r1.
 269                                         if i+2 > len(out) {
 270                                                 fmt.Fprintf(os.Stderr, "%s: not enough registers for int64 return\n", path)
 271                                                 os.Exit(1)
 272                                         }
 273                                         if endianness == "big-endian" {
 274                                                 reg = fmt.Sprintf("int64(r%d)<<32 | int64(r%d)", i, i+1)
 275                                         } else {
 276                                                 reg = fmt.Sprintf("int64(r%d)<<32 | int64(r%d)", i+1, i)
 277                                         }
 278                                         ret[i] = fmt.Sprintf("r%d", i)
 279                                         ret[i+1] = fmt.Sprintf("r%d", i+1)
 280                                 }
 281                                 if reg != "e1" {
 282                                         body += fmt.Sprintf("\t%s = %s(%s)\n", p.Name, p.Type, reg)
 283                                 }
 284                         }
 285                         if ret[0] == "_" && ret[1] == "_" && ret[2] == "_" {
 286                                 text += fmt.Sprintf("\t%s\n", call)
 287                         } else {
 288                                 text += fmt.Sprintf("\t%s, %s, %s := %s\n", ret[0], ret[1], ret[2], call)
 289                         }
 290                         text += body
 291
 292                         if doErrno {
 293                                 text += "\tif e1 != 0 {\n"
 294                                 text += "\t\terr = e1\n"
 295                                 text += "\t}\n"
 296                         }
 297                         text += "\treturn\n"
 298                         text += "}\n"
 299                 }
 300                 if err := s.Err(); err != nil {
 301                         fmt.Fprintf(os.Stderr, err.Error())
 302                         os.Exit(1)
 303                 }
 304                 file.Close()
 305         }
 306         imp := ""
 307         if pack != "unix" {
 308                 imp = "import \"golang.org/x/sys/unix\"\n"
 309
 310         }
 311         vardecls := "\t" + strings.Join(vars, ",\n\t")
 312         vardecls += " syscallFunc"
 313         fmt.Printf(srcTemplate, cmdLine(), buildTags(), pack, imp, dynimports, linknames, vardecls, text)
 314 }
 315
 316 const srcTemplate = `// %s
 317 // Code generated by the command above; see README.md. DO NOT EDIT.
 318
 319 // +build %s
 320
 321 package %s
 322
 323 import (
 324         "syscall"
 325         "unsafe"
 326 )
 327 %s
 328 %s
 329 %s
 330 var (
 331 %s
 332 )
 333
 334 %s
 335 `