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Diffstat (limited to 'src/cmd/newlink/prog.go')
| -rw-r--r-- | src/cmd/newlink/prog.go | 220 |
1 files changed, 0 insertions, 220 deletions
diff --git a/src/cmd/newlink/prog.go b/src/cmd/newlink/prog.go deleted file mode 100644 index 77fb1ece5b..0000000000 --- a/src/cmd/newlink/prog.go +++ /dev/null @@ -1,220 +0,0 @@ -// Copyright 2014 The Go Authors. All rights reserved. -// Use of this source code is governed by a BSD-style -// license that can be found in the LICENSE file. - -package main - -import ( - "cmd/internal/goobj" - "encoding/binary" - "fmt" - "go/build" - "io" - "os" - "runtime" -) - -// A Prog holds state for constructing an executable (program) image. -// -// The usual sequence of operations on a Prog is: -// -// p.init() -// p.scan(file) -// p.dead() -// p.runtime() -// p.layout() -// p.load() -// p.debug() -// p.write(w) -// -// p.init is in this file. The rest of the methods are in files -// named for the method. The convenience method p.link runs -// this sequence. -// -type Prog struct { - // Context - GOOS string // target operating system - GOARCH string // target architecture - Format string // desired file format ("elf", "macho", ...) - Error func(string) // called to report an error (if set) - NumError int // number of errors printed - StartSym string - - // Derived context - arch - formatter formatter - startSym goobj.SymID - pkgdir string - omitRuntime bool // do not load runtime package - - // Input - Packages map[string]*Package // loaded packages, by import path - Syms map[goobj.SymID]*Sym // defined symbols, by symbol ID - Missing map[goobj.SymID]bool // missing symbols - Dead map[goobj.SymID]bool // symbols removed as dead - SymOrder []*Sym // order syms were scanned - MaxVersion int // max SymID.Version, for generating fresh symbol IDs - - // Output - UnmappedSize Addr // size of unmapped region at address 0 - HeaderSize Addr // size of object file header - Entry Addr // virtual address where execution begins - Segments []*Segment // loaded memory segments -} - -// An arch describes architecture-dependent settings. -type arch struct { - byteorder binary.ByteOrder - ptrsize int - pcquantum int -} - -// A formatter takes care of the details of generating a particular -// kind of executable file. -type formatter interface { - // headerSize returns the footprint of the header for p - // in both virtual address space and file bytes. - // The footprint does not include any bytes stored at the - // end of the file. - headerSize(p *Prog) (virt, file Addr) - - // write writes the executable file for p to w. - write(w io.Writer, p *Prog) -} - -// An Addr represents a virtual memory address, a file address, or a size. -// It must be a uint64, not a uintptr, so that a 32-bit linker can still generate a 64-bit binary. -// It must be unsigned in order to link programs placed at very large start addresses. -// Math involving Addrs must be checked carefully not to require negative numbers. -type Addr uint64 - -// A Package is a Go package loaded from a file. -type Package struct { - *goobj.Package // table of contents - File string // file name for reopening - Syms []*Sym // symbols defined by this package -} - -// A Sym is a symbol defined in a loaded package. -type Sym struct { - *goobj.Sym // symbol metadata from package file - Package *Package // package defining symbol - Section *Section // section where symbol is placed in output program - Addr Addr // virtual address of symbol in output program - Bytes []byte // symbol data, for internally defined symbols -} - -// A Segment is a loaded memory segment. -// A Prog is expected to have segments named "text" and optionally "data", -// in that order, before any other segments. -type Segment struct { - Name string // name of segment: "text", "data", ... - VirtAddr Addr // virtual memory address of segment base - VirtSize Addr // size of segment in memory - FileOffset Addr // file offset of segment base - FileSize Addr // size of segment in file; can be less than VirtSize - Sections []*Section // sections inside segment - Data []byte // raw data of segment image -} - -// A Section is part of a loaded memory segment. -type Section struct { - Name string // name of section: "text", "rodata", "noptrbss", and so on - VirtAddr Addr // virtual memory address of section base - Size Addr // size of section in memory - Align Addr // required alignment - InFile bool // section has image data in file (like data, unlike bss) - Syms []*Sym // symbols stored in section - Segment *Segment // segment containing section -} - -func (p *Prog) errorf(format string, args ...interface{}) { - if p.Error != nil { - p.Error(fmt.Sprintf(format, args...)) - } else { - fmt.Fprintf(os.Stderr, format+"\n", args...) - } - p.NumError++ -} - -// link is the one-stop convenience method for running a link. -// It writes to w the object file generated from using mainFile as the main package. -func (p *Prog) link(w io.Writer, mainFile string) { - p.init() - p.scan(mainFile) - if p.NumError > 0 { - return - } - p.dead() - p.runtime() - p.autoData() - p.layout() - p.autoConst() - if p.NumError > 0 { - return - } - p.load() - if p.NumError > 0 { - return - } - p.debug() - if p.NumError > 0 { - return - } - p.write(w) -} - -// init initializes p for use by the other methods. -func (p *Prog) init() { - // Set default context if not overridden. - if p.GOOS == "" { - p.GOOS = build.Default.GOOS - } - if p.GOARCH == "" { - p.GOARCH = build.Default.GOARCH - } - if p.Format == "" { - p.Format = goosFormat[p.GOOS] - if p.Format == "" { - p.errorf("no default file format for GOOS %q", p.GOOS) - return - } - } - if p.StartSym == "" { - p.StartSym = fmt.Sprintf("_rt0_%s_%s", p.GOARCH, p.GOOS) - } - - // Derive internal context. - p.formatter = formatters[p.Format] - if p.formatter == nil { - p.errorf("unknown output file format %q", p.Format) - return - } - p.startSym = goobj.SymID{Name: p.StartSym} - arch, ok := arches[p.GOARCH] - if !ok { - p.errorf("unknown GOOS %q", p.GOOS) - return - } - p.arch = arch - - p.pkgdir = fmt.Sprintf("%s/pkg/%s_%s", runtime.GOROOT(), p.GOOS, p.GOARCH) -} - -// goosFormat records the default format for each known GOOS value. -var goosFormat = map[string]string{ - "darwin": "darwin", -} - -// formatters records the format implementation for each known format value. -var formatters = map[string]formatter{ - "darwin": machoFormat{}, -} - -var arches = map[string]arch{ - "amd64": { - byteorder: binary.LittleEndian, - ptrsize: 8, - pcquantum: 1, - }, -} |