1935 lines
57 KiB
Go
1935 lines
57 KiB
Go
// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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import (
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"bytes"
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"cmd/internal/pkgpath"
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"debug/elf"
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"debug/macho"
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"debug/pe"
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"fmt"
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"go/ast"
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"go/printer"
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"go/token"
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exec "internal/execabs"
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"internal/xcoff"
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"io"
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"os"
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"path/filepath"
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"regexp"
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"sort"
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"strings"
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"unicode"
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)
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var (
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conf = printer.Config{Mode: printer.SourcePos, Tabwidth: 8}
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noSourceConf = printer.Config{Tabwidth: 8}
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)
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// writeDefs creates output files to be compiled by gc and gcc.
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func (p *Package) writeDefs() {
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var fgo2, fc io.Writer
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f := creat(*objDir + "_cgo_gotypes.go")
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defer f.Close()
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fgo2 = f
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if *gccgo {
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f := creat(*objDir + "_cgo_defun.c")
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defer f.Close()
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fc = f
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}
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fm := creat(*objDir + "_cgo_main.c")
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var gccgoInit bytes.Buffer
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fflg := creat(*objDir + "_cgo_flags")
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var flags []string
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for k, v := range p.CgoFlags {
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flags = append(flags, fmt.Sprintf("_CGO_%s=%s", k, strings.Join(v, " ")))
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if k == "LDFLAGS" && !*gccgo {
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for _, arg := range v {
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fmt.Fprintf(fgo2, "//go:cgo_ldflag %q\n", arg)
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}
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}
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}
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sort.Strings(flags)
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for _, flag := range flags {
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fmt.Fprintln(fflg, flag)
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}
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fflg.Close()
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// Write C main file for using gcc to resolve imports.
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fmt.Fprintf(fm, "int main() { return 0; }\n")
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if *importRuntimeCgo {
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fmt.Fprintf(fm, "void crosscall2(void(*fn)(void*) __attribute__((unused)), void *a __attribute__((unused)), int c __attribute__((unused)), __SIZE_TYPE__ ctxt __attribute__((unused))) { }\n")
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fmt.Fprintf(fm, "__SIZE_TYPE__ _cgo_wait_runtime_init_done(void) { return 0; }\n")
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fmt.Fprintf(fm, "void _cgo_release_context(__SIZE_TYPE__ ctxt __attribute__((unused))) { }\n")
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fmt.Fprintf(fm, "char* _cgo_topofstack(void) { return (char*)0; }\n")
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} else {
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// If we're not importing runtime/cgo, we *are* runtime/cgo,
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// which provides these functions. We just need a prototype.
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fmt.Fprintf(fm, "void crosscall2(void(*fn)(void*), void *a, int c, __SIZE_TYPE__ ctxt);\n")
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fmt.Fprintf(fm, "__SIZE_TYPE__ _cgo_wait_runtime_init_done(void);\n")
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fmt.Fprintf(fm, "void _cgo_release_context(__SIZE_TYPE__);\n")
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}
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fmt.Fprintf(fm, "void _cgo_allocate(void *a __attribute__((unused)), int c __attribute__((unused))) { }\n")
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fmt.Fprintf(fm, "void _cgo_panic(void *a __attribute__((unused)), int c __attribute__((unused))) { }\n")
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fmt.Fprintf(fm, "void _cgo_reginit(void) { }\n")
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// Write second Go output: definitions of _C_xxx.
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// In a separate file so that the import of "unsafe" does not
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// pollute the original file.
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fmt.Fprintf(fgo2, "// Code generated by cmd/cgo; DO NOT EDIT.\n\n")
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fmt.Fprintf(fgo2, "package %s\n\n", p.PackageName)
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fmt.Fprintf(fgo2, "import \"unsafe\"\n\n")
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if !*gccgo && *importRuntimeCgo {
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fmt.Fprintf(fgo2, "import _ \"runtime/cgo\"\n\n")
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}
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if *importSyscall {
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fmt.Fprintf(fgo2, "import \"syscall\"\n\n")
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fmt.Fprintf(fgo2, "var _ syscall.Errno\n")
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}
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fmt.Fprintf(fgo2, "func _Cgo_ptr(ptr unsafe.Pointer) unsafe.Pointer { return ptr }\n\n")
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if !*gccgo {
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fmt.Fprintf(fgo2, "//go:linkname _Cgo_always_false runtime.cgoAlwaysFalse\n")
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fmt.Fprintf(fgo2, "var _Cgo_always_false bool\n")
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fmt.Fprintf(fgo2, "//go:linkname _Cgo_use runtime.cgoUse\n")
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fmt.Fprintf(fgo2, "func _Cgo_use(interface{})\n")
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}
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typedefNames := make([]string, 0, len(typedef))
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for name := range typedef {
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if name == "_Ctype_void" {
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// We provide an appropriate declaration for
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// _Ctype_void below (#39877).
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continue
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}
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typedefNames = append(typedefNames, name)
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}
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sort.Strings(typedefNames)
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for _, name := range typedefNames {
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def := typedef[name]
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if def.NotInHeap {
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fmt.Fprintf(fgo2, "//go:notinheap\n")
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}
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fmt.Fprintf(fgo2, "type %s ", name)
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// We don't have source info for these types, so write them out without source info.
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// Otherwise types would look like:
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//
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// type _Ctype_struct_cb struct {
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// //line :1
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// on_test *[0]byte
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// //line :1
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// }
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//
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// Which is not useful. Moreover we never override source info,
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// so subsequent source code uses the same source info.
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// Moreover, empty file name makes compile emit no source debug info at all.
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var buf bytes.Buffer
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noSourceConf.Fprint(&buf, fset, def.Go)
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if bytes.HasPrefix(buf.Bytes(), []byte("_Ctype_")) ||
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strings.HasPrefix(name, "_Ctype_enum_") ||
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strings.HasPrefix(name, "_Ctype_union_") {
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// This typedef is of the form `typedef a b` and should be an alias.
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fmt.Fprintf(fgo2, "= ")
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}
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fmt.Fprintf(fgo2, "%s", buf.Bytes())
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fmt.Fprintf(fgo2, "\n\n")
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}
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fmt.Fprintf(fgo2, "//go:notinheap\ntype _Ctype_void_notinheap struct{}\n\n")
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if *gccgo {
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fmt.Fprintf(fgo2, "type _Ctype_void byte\n")
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} else {
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fmt.Fprintf(fgo2, "type _Ctype_void [0]byte\n")
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}
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if *gccgo {
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fmt.Fprint(fgo2, gccgoGoProlog)
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fmt.Fprint(fc, p.cPrologGccgo())
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} else {
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fmt.Fprint(fgo2, goProlog)
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}
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if fc != nil {
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fmt.Fprintf(fc, "#line 1 \"cgo-generated-wrappers\"\n")
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}
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if fm != nil {
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fmt.Fprintf(fm, "#line 1 \"cgo-generated-wrappers\"\n")
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}
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gccgoSymbolPrefix := p.gccgoSymbolPrefix()
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cVars := make(map[string]bool)
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for _, key := range nameKeys(p.Name) {
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n := p.Name[key]
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if !n.IsVar() {
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continue
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}
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if !cVars[n.C] {
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if *gccgo {
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fmt.Fprintf(fc, "extern byte *%s;\n", n.C)
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} else {
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// Force a reference to all symbols so that
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// the external linker will add DT_NEEDED
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// entries as needed on ELF systems.
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// Treat function variables differently
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// to avoid type confict errors from LTO
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// (Link Time Optimization).
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if n.Kind == "fpvar" {
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fmt.Fprintf(fm, "extern void %s();\n", n.C)
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} else {
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fmt.Fprintf(fm, "extern char %s[];\n", n.C)
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fmt.Fprintf(fm, "void *_cgohack_%s = %s;\n\n", n.C, n.C)
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}
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fmt.Fprintf(fgo2, "//go:linkname __cgo_%s %s\n", n.C, n.C)
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fmt.Fprintf(fgo2, "//go:cgo_import_static %s\n", n.C)
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fmt.Fprintf(fgo2, "var __cgo_%s byte\n", n.C)
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}
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cVars[n.C] = true
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}
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var node ast.Node
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if n.Kind == "var" {
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node = &ast.StarExpr{X: n.Type.Go}
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} else if n.Kind == "fpvar" {
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node = n.Type.Go
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} else {
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panic(fmt.Errorf("invalid var kind %q", n.Kind))
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}
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if *gccgo {
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fmt.Fprintf(fc, `extern void *%s __asm__("%s.%s");`, n.Mangle, gccgoSymbolPrefix, gccgoToSymbol(n.Mangle))
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fmt.Fprintf(&gccgoInit, "\t%s = &%s;\n", n.Mangle, n.C)
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fmt.Fprintf(fc, "\n")
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}
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fmt.Fprintf(fgo2, "var %s ", n.Mangle)
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conf.Fprint(fgo2, fset, node)
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if !*gccgo {
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fmt.Fprintf(fgo2, " = (")
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conf.Fprint(fgo2, fset, node)
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fmt.Fprintf(fgo2, ")(unsafe.Pointer(&__cgo_%s))", n.C)
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}
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fmt.Fprintf(fgo2, "\n")
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}
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if *gccgo {
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fmt.Fprintf(fc, "\n")
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}
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for _, key := range nameKeys(p.Name) {
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n := p.Name[key]
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if n.Const != "" {
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fmt.Fprintf(fgo2, "const %s = %s\n", n.Mangle, n.Const)
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}
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}
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fmt.Fprintf(fgo2, "\n")
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callsMalloc := false
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for _, key := range nameKeys(p.Name) {
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n := p.Name[key]
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if n.FuncType != nil {
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p.writeDefsFunc(fgo2, n, &callsMalloc)
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}
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}
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fgcc := creat(*objDir + "_cgo_export.c")
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fgcch := creat(*objDir + "_cgo_export.h")
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if *gccgo {
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p.writeGccgoExports(fgo2, fm, fgcc, fgcch)
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} else {
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p.writeExports(fgo2, fm, fgcc, fgcch)
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}
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if callsMalloc && !*gccgo {
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fmt.Fprint(fgo2, strings.Replace(cMallocDefGo, "PREFIX", cPrefix, -1))
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fmt.Fprint(fgcc, strings.Replace(strings.Replace(cMallocDefC, "PREFIX", cPrefix, -1), "PACKED", p.packedAttribute(), -1))
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}
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if err := fgcc.Close(); err != nil {
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fatalf("%s", err)
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}
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if err := fgcch.Close(); err != nil {
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fatalf("%s", err)
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}
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if *exportHeader != "" && len(p.ExpFunc) > 0 {
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fexp := creat(*exportHeader)
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fgcch, err := os.Open(*objDir + "_cgo_export.h")
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if err != nil {
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fatalf("%s", err)
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}
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defer fgcch.Close()
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_, err = io.Copy(fexp, fgcch)
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if err != nil {
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fatalf("%s", err)
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}
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if err = fexp.Close(); err != nil {
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fatalf("%s", err)
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}
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}
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init := gccgoInit.String()
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if init != "" {
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// The init function does nothing but simple
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// assignments, so it won't use much stack space, so
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// it's OK to not split the stack. Splitting the stack
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// can run into a bug in clang (as of 2018-11-09):
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// this is a leaf function, and when clang sees a leaf
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// function it won't emit the split stack prologue for
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// the function. However, if this function refers to a
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// non-split-stack function, which will happen if the
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// cgo code refers to a C function not compiled with
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// -fsplit-stack, then the linker will think that it
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// needs to adjust the split stack prologue, but there
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// won't be one. Marking the function explicitly
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// no_split_stack works around this problem by telling
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// the linker that it's OK if there is no split stack
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// prologue.
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fmt.Fprintln(fc, "static void init(void) __attribute__ ((constructor, no_split_stack));")
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fmt.Fprintln(fc, "static void init(void) {")
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fmt.Fprint(fc, init)
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fmt.Fprintln(fc, "}")
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}
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}
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// elfImportedSymbols is like elf.File.ImportedSymbols, but it
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// includes weak symbols.
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//
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// A bug in some versions of LLD (at least LLD 8) cause it to emit
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// several pthreads symbols as weak, but we need to import those. See
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// issue #31912 or https://bugs.llvm.org/show_bug.cgi?id=42442.
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//
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// When doing external linking, we hand everything off to the external
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// linker, which will create its own dynamic symbol tables. For
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// internal linking, this may turn weak imports into strong imports,
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// which could cause dynamic linking to fail if a symbol really isn't
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// defined. However, the standard library depends on everything it
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// imports, and this is the primary use of dynamic symbol tables with
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// internal linking.
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func elfImportedSymbols(f *elf.File) []elf.ImportedSymbol {
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syms, _ := f.DynamicSymbols()
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var imports []elf.ImportedSymbol
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for _, s := range syms {
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if (elf.ST_BIND(s.Info) == elf.STB_GLOBAL || elf.ST_BIND(s.Info) == elf.STB_WEAK) && s.Section == elf.SHN_UNDEF {
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imports = append(imports, elf.ImportedSymbol{
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Name: s.Name,
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Library: s.Library,
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Version: s.Version,
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})
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}
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}
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return imports
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}
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func dynimport(obj string) {
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stdout := os.Stdout
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if *dynout != "" {
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f, err := os.Create(*dynout)
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if err != nil {
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fatalf("%s", err)
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}
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stdout = f
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}
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fmt.Fprintf(stdout, "package %s\n", *dynpackage)
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if f, err := elf.Open(obj); err == nil {
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if *dynlinker {
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// Emit the cgo_dynamic_linker line.
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if sec := f.Section(".interp"); sec != nil {
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if data, err := sec.Data(); err == nil && len(data) > 1 {
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// skip trailing \0 in data
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fmt.Fprintf(stdout, "//go:cgo_dynamic_linker %q\n", string(data[:len(data)-1]))
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}
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}
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}
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sym := elfImportedSymbols(f)
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for _, s := range sym {
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targ := s.Name
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if s.Version != "" {
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targ += "#" + s.Version
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}
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checkImportSymName(s.Name)
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checkImportSymName(targ)
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fmt.Fprintf(stdout, "//go:cgo_import_dynamic %s %s %q\n", s.Name, targ, s.Library)
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}
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lib, _ := f.ImportedLibraries()
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for _, l := range lib {
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fmt.Fprintf(stdout, "//go:cgo_import_dynamic _ _ %q\n", l)
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}
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return
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}
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if f, err := macho.Open(obj); err == nil {
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sym, _ := f.ImportedSymbols()
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for _, s := range sym {
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if len(s) > 0 && s[0] == '_' {
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s = s[1:]
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}
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checkImportSymName(s)
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fmt.Fprintf(stdout, "//go:cgo_import_dynamic %s %s %q\n", s, s, "")
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}
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lib, _ := f.ImportedLibraries()
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for _, l := range lib {
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fmt.Fprintf(stdout, "//go:cgo_import_dynamic _ _ %q\n", l)
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}
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return
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}
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if f, err := pe.Open(obj); err == nil {
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sym, _ := f.ImportedSymbols()
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for _, s := range sym {
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ss := strings.Split(s, ":")
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name := strings.Split(ss[0], "@")[0]
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checkImportSymName(name)
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checkImportSymName(ss[0])
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fmt.Fprintf(stdout, "//go:cgo_import_dynamic %s %s %q\n", name, ss[0], strings.ToLower(ss[1]))
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}
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return
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}
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if f, err := xcoff.Open(obj); err == nil {
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sym, err := f.ImportedSymbols()
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if err != nil {
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fatalf("cannot load imported symbols from XCOFF file %s: %v", obj, err)
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}
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for _, s := range sym {
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if s.Name == "runtime_rt0_go" || s.Name == "_rt0_ppc64_aix_lib" {
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// These symbols are imported by runtime/cgo but
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// must not be added to _cgo_import.go as there are
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// Go symbols.
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continue
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}
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checkImportSymName(s.Name)
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fmt.Fprintf(stdout, "//go:cgo_import_dynamic %s %s %q\n", s.Name, s.Name, s.Library)
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}
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lib, err := f.ImportedLibraries()
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if err != nil {
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fatalf("cannot load imported libraries from XCOFF file %s: %v", obj, err)
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}
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for _, l := range lib {
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fmt.Fprintf(stdout, "//go:cgo_import_dynamic _ _ %q\n", l)
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}
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return
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}
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fatalf("cannot parse %s as ELF, Mach-O, PE or XCOFF", obj)
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}
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// checkImportSymName checks a symbol name we are going to emit as part
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// of a //go:cgo_import_dynamic pragma. These names come from object
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// files, so they may be corrupt. We are going to emit them unquoted,
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// so while they don't need to be valid symbol names (and in some cases,
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// involving symbol versions, they won't be) they must contain only
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// graphic characters and must not contain Go comments.
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func checkImportSymName(s string) {
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for _, c := range s {
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if !unicode.IsGraphic(c) || unicode.IsSpace(c) {
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fatalf("dynamic symbol %q contains unsupported character", s)
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}
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}
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if strings.Index(s, "//") >= 0 || strings.Index(s, "/*") >= 0 {
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fatalf("dynamic symbol %q contains Go comment")
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}
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}
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// Construct a gcc struct matching the gc argument frame.
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// Assumes that in gcc, char is 1 byte, short 2 bytes, int 4 bytes, long long 8 bytes.
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// These assumptions are checked by the gccProlog.
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// Also assumes that gc convention is to word-align the
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// input and output parameters.
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func (p *Package) structType(n *Name) (string, int64) {
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var buf bytes.Buffer
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fmt.Fprint(&buf, "struct {\n")
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off := int64(0)
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for i, t := range n.FuncType.Params {
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if off%t.Align != 0 {
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pad := t.Align - off%t.Align
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fmt.Fprintf(&buf, "\t\tchar __pad%d[%d];\n", off, pad)
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off += pad
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}
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c := t.Typedef
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if c == "" {
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c = t.C.String()
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|
}
|
|
fmt.Fprintf(&buf, "\t\t%s p%d;\n", c, i)
|
|
off += t.Size
|
|
}
|
|
if off%p.PtrSize != 0 {
|
|
pad := p.PtrSize - off%p.PtrSize
|
|
fmt.Fprintf(&buf, "\t\tchar __pad%d[%d];\n", off, pad)
|
|
off += pad
|
|
}
|
|
if t := n.FuncType.Result; t != nil {
|
|
if off%t.Align != 0 {
|
|
pad := t.Align - off%t.Align
|
|
fmt.Fprintf(&buf, "\t\tchar __pad%d[%d];\n", off, pad)
|
|
off += pad
|
|
}
|
|
fmt.Fprintf(&buf, "\t\t%s r;\n", t.C)
|
|
off += t.Size
|
|
}
|
|
if off%p.PtrSize != 0 {
|
|
pad := p.PtrSize - off%p.PtrSize
|
|
fmt.Fprintf(&buf, "\t\tchar __pad%d[%d];\n", off, pad)
|
|
off += pad
|
|
}
|
|
if off == 0 {
|
|
fmt.Fprintf(&buf, "\t\tchar unused;\n") // avoid empty struct
|
|
}
|
|
fmt.Fprintf(&buf, "\t}")
|
|
return buf.String(), off
|
|
}
|
|
|
|
func (p *Package) writeDefsFunc(fgo2 io.Writer, n *Name, callsMalloc *bool) {
|
|
name := n.Go
|
|
gtype := n.FuncType.Go
|
|
void := gtype.Results == nil || len(gtype.Results.List) == 0
|
|
if n.AddError {
|
|
// Add "error" to return type list.
|
|
// Type list is known to be 0 or 1 element - it's a C function.
|
|
err := &ast.Field{Type: ast.NewIdent("error")}
|
|
l := gtype.Results.List
|
|
if len(l) == 0 {
|
|
l = []*ast.Field{err}
|
|
} else {
|
|
l = []*ast.Field{l[0], err}
|
|
}
|
|
t := new(ast.FuncType)
|
|
*t = *gtype
|
|
t.Results = &ast.FieldList{List: l}
|
|
gtype = t
|
|
}
|
|
|
|
// Go func declaration.
|
|
d := &ast.FuncDecl{
|
|
Name: ast.NewIdent(n.Mangle),
|
|
Type: gtype,
|
|
}
|
|
|
|
// Builtins defined in the C prolog.
|
|
inProlog := builtinDefs[name] != ""
|
|
cname := fmt.Sprintf("_cgo%s%s", cPrefix, n.Mangle)
|
|
paramnames := []string(nil)
|
|
if d.Type.Params != nil {
|
|
for i, param := range d.Type.Params.List {
|
|
paramName := fmt.Sprintf("p%d", i)
|
|
param.Names = []*ast.Ident{ast.NewIdent(paramName)}
|
|
paramnames = append(paramnames, paramName)
|
|
}
|
|
}
|
|
|
|
if *gccgo {
|
|
// Gccgo style hooks.
|
|
fmt.Fprint(fgo2, "\n")
|
|
conf.Fprint(fgo2, fset, d)
|
|
fmt.Fprint(fgo2, " {\n")
|
|
if !inProlog {
|
|
fmt.Fprint(fgo2, "\tdefer syscall.CgocallDone()\n")
|
|
fmt.Fprint(fgo2, "\tsyscall.Cgocall()\n")
|
|
}
|
|
if n.AddError {
|
|
fmt.Fprint(fgo2, "\tsyscall.SetErrno(0)\n")
|
|
}
|
|
fmt.Fprint(fgo2, "\t")
|
|
if !void {
|
|
fmt.Fprint(fgo2, "r := ")
|
|
}
|
|
fmt.Fprintf(fgo2, "%s(%s)\n", cname, strings.Join(paramnames, ", "))
|
|
|
|
if n.AddError {
|
|
fmt.Fprint(fgo2, "\te := syscall.GetErrno()\n")
|
|
fmt.Fprint(fgo2, "\tif e != 0 {\n")
|
|
fmt.Fprint(fgo2, "\t\treturn ")
|
|
if !void {
|
|
fmt.Fprint(fgo2, "r, ")
|
|
}
|
|
fmt.Fprint(fgo2, "e\n")
|
|
fmt.Fprint(fgo2, "\t}\n")
|
|
fmt.Fprint(fgo2, "\treturn ")
|
|
if !void {
|
|
fmt.Fprint(fgo2, "r, ")
|
|
}
|
|
fmt.Fprint(fgo2, "nil\n")
|
|
} else if !void {
|
|
fmt.Fprint(fgo2, "\treturn r\n")
|
|
}
|
|
|
|
fmt.Fprint(fgo2, "}\n")
|
|
|
|
// declare the C function.
|
|
fmt.Fprintf(fgo2, "//extern %s\n", cname)
|
|
d.Name = ast.NewIdent(cname)
|
|
if n.AddError {
|
|
l := d.Type.Results.List
|
|
d.Type.Results.List = l[:len(l)-1]
|
|
}
|
|
conf.Fprint(fgo2, fset, d)
|
|
fmt.Fprint(fgo2, "\n")
|
|
|
|
return
|
|
}
|
|
|
|
if inProlog {
|
|
fmt.Fprint(fgo2, builtinDefs[name])
|
|
if strings.Contains(builtinDefs[name], "_cgo_cmalloc") {
|
|
*callsMalloc = true
|
|
}
|
|
return
|
|
}
|
|
|
|
// Wrapper calls into gcc, passing a pointer to the argument frame.
|
|
fmt.Fprintf(fgo2, "//go:cgo_import_static %s\n", cname)
|
|
fmt.Fprintf(fgo2, "//go:linkname __cgofn_%s %s\n", cname, cname)
|
|
fmt.Fprintf(fgo2, "var __cgofn_%s byte\n", cname)
|
|
fmt.Fprintf(fgo2, "var %s = unsafe.Pointer(&__cgofn_%s)\n", cname, cname)
|
|
|
|
nret := 0
|
|
if !void {
|
|
d.Type.Results.List[0].Names = []*ast.Ident{ast.NewIdent("r1")}
|
|
nret = 1
|
|
}
|
|
if n.AddError {
|
|
d.Type.Results.List[nret].Names = []*ast.Ident{ast.NewIdent("r2")}
|
|
}
|
|
|
|
fmt.Fprint(fgo2, "\n")
|
|
fmt.Fprint(fgo2, "//go:cgo_unsafe_args\n")
|
|
conf.Fprint(fgo2, fset, d)
|
|
fmt.Fprint(fgo2, " {\n")
|
|
|
|
// NOTE: Using uintptr to hide from escape analysis.
|
|
arg := "0"
|
|
if len(paramnames) > 0 {
|
|
arg = "uintptr(unsafe.Pointer(&p0))"
|
|
} else if !void {
|
|
arg = "uintptr(unsafe.Pointer(&r1))"
|
|
}
|
|
|
|
prefix := ""
|
|
if n.AddError {
|
|
prefix = "errno := "
|
|
}
|
|
fmt.Fprintf(fgo2, "\t%s_cgo_runtime_cgocall(%s, %s)\n", prefix, cname, arg)
|
|
if n.AddError {
|
|
fmt.Fprintf(fgo2, "\tif errno != 0 { r2 = syscall.Errno(errno) }\n")
|
|
}
|
|
fmt.Fprintf(fgo2, "\tif _Cgo_always_false {\n")
|
|
if d.Type.Params != nil {
|
|
for i := range d.Type.Params.List {
|
|
fmt.Fprintf(fgo2, "\t\t_Cgo_use(p%d)\n", i)
|
|
}
|
|
}
|
|
fmt.Fprintf(fgo2, "\t}\n")
|
|
fmt.Fprintf(fgo2, "\treturn\n")
|
|
fmt.Fprintf(fgo2, "}\n")
|
|
}
|
|
|
|
// writeOutput creates stubs for a specific source file to be compiled by gc
|
|
func (p *Package) writeOutput(f *File, srcfile string) {
|
|
base := srcfile
|
|
if strings.HasSuffix(base, ".go") {
|
|
base = base[0 : len(base)-3]
|
|
}
|
|
base = filepath.Base(base)
|
|
fgo1 := creat(*objDir + base + ".cgo1.go")
|
|
fgcc := creat(*objDir + base + ".cgo2.c")
|
|
|
|
p.GoFiles = append(p.GoFiles, base+".cgo1.go")
|
|
p.GccFiles = append(p.GccFiles, base+".cgo2.c")
|
|
|
|
// Write Go output: Go input with rewrites of C.xxx to _C_xxx.
|
|
fmt.Fprintf(fgo1, "// Code generated by cmd/cgo; DO NOT EDIT.\n\n")
|
|
fmt.Fprintf(fgo1, "//line %s:1:1\n", srcfile)
|
|
fgo1.Write(f.Edit.Bytes())
|
|
|
|
// While we process the vars and funcs, also write gcc output.
|
|
// Gcc output starts with the preamble.
|
|
fmt.Fprintf(fgcc, "%s\n", builtinProlog)
|
|
fmt.Fprintf(fgcc, "%s\n", f.Preamble)
|
|
fmt.Fprintf(fgcc, "%s\n", gccProlog)
|
|
fmt.Fprintf(fgcc, "%s\n", tsanProlog)
|
|
fmt.Fprintf(fgcc, "%s\n", msanProlog)
|
|
|
|
for _, key := range nameKeys(f.Name) {
|
|
n := f.Name[key]
|
|
if n.FuncType != nil {
|
|
p.writeOutputFunc(fgcc, n)
|
|
}
|
|
}
|
|
|
|
fgo1.Close()
|
|
fgcc.Close()
|
|
}
|
|
|
|
// fixGo converts the internal Name.Go field into the name we should show
|
|
// to users in error messages. There's only one for now: on input we rewrite
|
|
// C.malloc into C._CMalloc, so change it back here.
|
|
func fixGo(name string) string {
|
|
if name == "_CMalloc" {
|
|
return "malloc"
|
|
}
|
|
return name
|
|
}
|
|
|
|
var isBuiltin = map[string]bool{
|
|
"_Cfunc_CString": true,
|
|
"_Cfunc_CBytes": true,
|
|
"_Cfunc_GoString": true,
|
|
"_Cfunc_GoStringN": true,
|
|
"_Cfunc_GoBytes": true,
|
|
"_Cfunc__CMalloc": true,
|
|
}
|
|
|
|
func (p *Package) writeOutputFunc(fgcc *os.File, n *Name) {
|
|
name := n.Mangle
|
|
if isBuiltin[name] || p.Written[name] {
|
|
// The builtins are already defined in the C prolog, and we don't
|
|
// want to duplicate function definitions we've already done.
|
|
return
|
|
}
|
|
p.Written[name] = true
|
|
|
|
if *gccgo {
|
|
p.writeGccgoOutputFunc(fgcc, n)
|
|
return
|
|
}
|
|
|
|
ctype, _ := p.structType(n)
|
|
|
|
// Gcc wrapper unpacks the C argument struct
|
|
// and calls the actual C function.
|
|
fmt.Fprintf(fgcc, "CGO_NO_SANITIZE_THREAD\n")
|
|
if n.AddError {
|
|
fmt.Fprintf(fgcc, "int\n")
|
|
} else {
|
|
fmt.Fprintf(fgcc, "void\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "_cgo%s%s(void *v)\n", cPrefix, n.Mangle)
|
|
fmt.Fprintf(fgcc, "{\n")
|
|
if n.AddError {
|
|
fmt.Fprintf(fgcc, "\tint _cgo_errno;\n")
|
|
}
|
|
// We're trying to write a gcc struct that matches gc's layout.
|
|
// Use packed attribute to force no padding in this struct in case
|
|
// gcc has different packing requirements.
|
|
fmt.Fprintf(fgcc, "\t%s %v *_cgo_a = v;\n", ctype, p.packedAttribute())
|
|
if n.FuncType.Result != nil {
|
|
// Save the stack top for use below.
|
|
fmt.Fprintf(fgcc, "\tchar *_cgo_stktop = _cgo_topofstack();\n")
|
|
}
|
|
tr := n.FuncType.Result
|
|
if tr != nil {
|
|
fmt.Fprintf(fgcc, "\t__typeof__(_cgo_a->r) _cgo_r;\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_acquire();\n")
|
|
if n.AddError {
|
|
fmt.Fprintf(fgcc, "\terrno = 0;\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "\t")
|
|
if tr != nil {
|
|
fmt.Fprintf(fgcc, "_cgo_r = ")
|
|
if c := tr.C.String(); c[len(c)-1] == '*' {
|
|
fmt.Fprint(fgcc, "(__typeof__(_cgo_a->r)) ")
|
|
}
|
|
}
|
|
if n.Kind == "macro" {
|
|
fmt.Fprintf(fgcc, "%s;\n", n.C)
|
|
} else {
|
|
fmt.Fprintf(fgcc, "%s(", n.C)
|
|
for i := range n.FuncType.Params {
|
|
if i > 0 {
|
|
fmt.Fprintf(fgcc, ", ")
|
|
}
|
|
fmt.Fprintf(fgcc, "_cgo_a->p%d", i)
|
|
}
|
|
fmt.Fprintf(fgcc, ");\n")
|
|
}
|
|
if n.AddError {
|
|
fmt.Fprintf(fgcc, "\t_cgo_errno = errno;\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_release();\n")
|
|
if n.FuncType.Result != nil {
|
|
// The cgo call may have caused a stack copy (via a callback).
|
|
// Adjust the return value pointer appropriately.
|
|
fmt.Fprintf(fgcc, "\t_cgo_a = (void*)((char*)_cgo_a + (_cgo_topofstack() - _cgo_stktop));\n")
|
|
// Save the return value.
|
|
fmt.Fprintf(fgcc, "\t_cgo_a->r = _cgo_r;\n")
|
|
// The return value is on the Go stack. If we are using msan,
|
|
// and if the C value is partially or completely uninitialized,
|
|
// the assignment will mark the Go stack as uninitialized.
|
|
// The Go compiler does not update msan for changes to the
|
|
// stack. It is possible that the stack will remain
|
|
// uninitialized, and then later be used in a way that is
|
|
// visible to msan, possibly leading to a false positive.
|
|
// Mark the stack space as written, to avoid this problem.
|
|
// See issue 26209.
|
|
fmt.Fprintf(fgcc, "\t_cgo_msan_write(&_cgo_a->r, sizeof(_cgo_a->r));\n")
|
|
}
|
|
if n.AddError {
|
|
fmt.Fprintf(fgcc, "\treturn _cgo_errno;\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "}\n")
|
|
fmt.Fprintf(fgcc, "\n")
|
|
}
|
|
|
|
// Write out a wrapper for a function when using gccgo. This is a
|
|
// simple wrapper that just calls the real function. We only need a
|
|
// wrapper to support static functions in the prologue--without a
|
|
// wrapper, we can't refer to the function, since the reference is in
|
|
// a different file.
|
|
func (p *Package) writeGccgoOutputFunc(fgcc *os.File, n *Name) {
|
|
fmt.Fprintf(fgcc, "CGO_NO_SANITIZE_THREAD\n")
|
|
if t := n.FuncType.Result; t != nil {
|
|
fmt.Fprintf(fgcc, "%s\n", t.C.String())
|
|
} else {
|
|
fmt.Fprintf(fgcc, "void\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "_cgo%s%s(", cPrefix, n.Mangle)
|
|
for i, t := range n.FuncType.Params {
|
|
if i > 0 {
|
|
fmt.Fprintf(fgcc, ", ")
|
|
}
|
|
c := t.Typedef
|
|
if c == "" {
|
|
c = t.C.String()
|
|
}
|
|
fmt.Fprintf(fgcc, "%s p%d", c, i)
|
|
}
|
|
fmt.Fprintf(fgcc, ")\n")
|
|
fmt.Fprintf(fgcc, "{\n")
|
|
if t := n.FuncType.Result; t != nil {
|
|
fmt.Fprintf(fgcc, "\t%s _cgo_r;\n", t.C.String())
|
|
}
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_acquire();\n")
|
|
fmt.Fprintf(fgcc, "\t")
|
|
if t := n.FuncType.Result; t != nil {
|
|
fmt.Fprintf(fgcc, "_cgo_r = ")
|
|
// Cast to void* to avoid warnings due to omitted qualifiers.
|
|
if c := t.C.String(); c[len(c)-1] == '*' {
|
|
fmt.Fprintf(fgcc, "(void*)")
|
|
}
|
|
}
|
|
if n.Kind == "macro" {
|
|
fmt.Fprintf(fgcc, "%s;\n", n.C)
|
|
} else {
|
|
fmt.Fprintf(fgcc, "%s(", n.C)
|
|
for i := range n.FuncType.Params {
|
|
if i > 0 {
|
|
fmt.Fprintf(fgcc, ", ")
|
|
}
|
|
fmt.Fprintf(fgcc, "p%d", i)
|
|
}
|
|
fmt.Fprintf(fgcc, ");\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_release();\n")
|
|
if t := n.FuncType.Result; t != nil {
|
|
fmt.Fprintf(fgcc, "\treturn ")
|
|
// Cast to void* to avoid warnings due to omitted qualifiers
|
|
// and explicit incompatible struct types.
|
|
if c := t.C.String(); c[len(c)-1] == '*' {
|
|
fmt.Fprintf(fgcc, "(void*)")
|
|
}
|
|
fmt.Fprintf(fgcc, "_cgo_r;\n")
|
|
}
|
|
fmt.Fprintf(fgcc, "}\n")
|
|
fmt.Fprintf(fgcc, "\n")
|
|
}
|
|
|
|
// packedAttribute returns host compiler struct attribute that will be
|
|
// used to match gc's struct layout. For example, on 386 Windows,
|
|
// gcc wants to 8-align int64s, but gc does not.
|
|
// Use __gcc_struct__ to work around https://gcc.gnu.org/PR52991 on x86,
|
|
// and https://golang.org/issue/5603.
|
|
func (p *Package) packedAttribute() string {
|
|
s := "__attribute__((__packed__"
|
|
if !p.GccIsClang && (goarch == "amd64" || goarch == "386") {
|
|
s += ", __gcc_struct__"
|
|
}
|
|
return s + "))"
|
|
}
|
|
|
|
// exportParamName returns the value of param as it should be
|
|
// displayed in a c header file. If param contains any non-ASCII
|
|
// characters, this function will return the character p followed by
|
|
// the value of position; otherwise, this function will return the
|
|
// value of param.
|
|
func exportParamName(param string, position int) string {
|
|
if param == "" {
|
|
return fmt.Sprintf("p%d", position)
|
|
}
|
|
|
|
pname := param
|
|
|
|
for i := 0; i < len(param); i++ {
|
|
if param[i] > unicode.MaxASCII {
|
|
pname = fmt.Sprintf("p%d", position)
|
|
break
|
|
}
|
|
}
|
|
|
|
return pname
|
|
}
|
|
|
|
// Write out the various stubs we need to support functions exported
|
|
// from Go so that they are callable from C.
|
|
func (p *Package) writeExports(fgo2, fm, fgcc, fgcch io.Writer) {
|
|
p.writeExportHeader(fgcch)
|
|
|
|
fmt.Fprintf(fgcc, "/* Code generated by cmd/cgo; DO NOT EDIT. */\n\n")
|
|
fmt.Fprintf(fgcc, "#include <stdlib.h>\n")
|
|
fmt.Fprintf(fgcc, "#include \"_cgo_export.h\"\n\n")
|
|
|
|
// We use packed structs, but they are always aligned.
|
|
// The pragmas and address-of-packed-member are only recognized as
|
|
// warning groups in clang 4.0+, so ignore unknown pragmas first.
|
|
fmt.Fprintf(fgcc, "#pragma GCC diagnostic ignored \"-Wunknown-pragmas\"\n")
|
|
fmt.Fprintf(fgcc, "#pragma GCC diagnostic ignored \"-Wpragmas\"\n")
|
|
fmt.Fprintf(fgcc, "#pragma GCC diagnostic ignored \"-Waddress-of-packed-member\"\n")
|
|
|
|
fmt.Fprintf(fgcc, "extern void crosscall2(void (*fn)(void *), void *, int, __SIZE_TYPE__);\n")
|
|
fmt.Fprintf(fgcc, "extern __SIZE_TYPE__ _cgo_wait_runtime_init_done(void);\n")
|
|
fmt.Fprintf(fgcc, "extern void _cgo_release_context(__SIZE_TYPE__);\n\n")
|
|
fmt.Fprintf(fgcc, "extern char* _cgo_topofstack(void);")
|
|
fmt.Fprintf(fgcc, "%s\n", tsanProlog)
|
|
fmt.Fprintf(fgcc, "%s\n", msanProlog)
|
|
|
|
for _, exp := range p.ExpFunc {
|
|
fn := exp.Func
|
|
|
|
// Construct a struct that will be used to communicate
|
|
// arguments from C to Go. The C and Go definitions
|
|
// just have to agree. The gcc struct will be compiled
|
|
// with __attribute__((packed)) so all padding must be
|
|
// accounted for explicitly.
|
|
ctype := "struct {\n"
|
|
gotype := new(bytes.Buffer)
|
|
fmt.Fprintf(gotype, "struct {\n")
|
|
off := int64(0)
|
|
npad := 0
|
|
argField := func(typ ast.Expr, namePat string, args ...interface{}) {
|
|
name := fmt.Sprintf(namePat, args...)
|
|
t := p.cgoType(typ)
|
|
if off%t.Align != 0 {
|
|
pad := t.Align - off%t.Align
|
|
ctype += fmt.Sprintf("\t\tchar __pad%d[%d];\n", npad, pad)
|
|
off += pad
|
|
npad++
|
|
}
|
|
ctype += fmt.Sprintf("\t\t%s %s;\n", t.C, name)
|
|
fmt.Fprintf(gotype, "\t\t%s ", name)
|
|
noSourceConf.Fprint(gotype, fset, typ)
|
|
fmt.Fprintf(gotype, "\n")
|
|
off += t.Size
|
|
}
|
|
if fn.Recv != nil {
|
|
argField(fn.Recv.List[0].Type, "recv")
|
|
}
|
|
fntype := fn.Type
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
argField(atype, "p%d", i)
|
|
})
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
argField(atype, "r%d", i)
|
|
})
|
|
if ctype == "struct {\n" {
|
|
ctype += "\t\tchar unused;\n" // avoid empty struct
|
|
}
|
|
ctype += "\t}"
|
|
fmt.Fprintf(gotype, "\t}")
|
|
|
|
// Get the return type of the wrapper function
|
|
// compiled by gcc.
|
|
gccResult := ""
|
|
if fntype.Results == nil || len(fntype.Results.List) == 0 {
|
|
gccResult = "void"
|
|
} else if len(fntype.Results.List) == 1 && len(fntype.Results.List[0].Names) <= 1 {
|
|
gccResult = p.cgoType(fntype.Results.List[0].Type).C.String()
|
|
} else {
|
|
fmt.Fprintf(fgcch, "\n/* Return type for %s */\n", exp.ExpName)
|
|
fmt.Fprintf(fgcch, "struct %s_return {\n", exp.ExpName)
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
fmt.Fprintf(fgcch, "\t%s r%d;", p.cgoType(atype).C, i)
|
|
if len(aname) > 0 {
|
|
fmt.Fprintf(fgcch, " /* %s */", aname)
|
|
}
|
|
fmt.Fprint(fgcch, "\n")
|
|
})
|
|
fmt.Fprintf(fgcch, "};\n")
|
|
gccResult = "struct " + exp.ExpName + "_return"
|
|
}
|
|
|
|
// Build the wrapper function compiled by gcc.
|
|
gccExport := ""
|
|
if goos == "windows" {
|
|
gccExport = "__declspec(dllexport) "
|
|
}
|
|
s := fmt.Sprintf("%s%s %s(", gccExport, gccResult, exp.ExpName)
|
|
if fn.Recv != nil {
|
|
s += p.cgoType(fn.Recv.List[0].Type).C.String()
|
|
s += " recv"
|
|
}
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 || fn.Recv != nil {
|
|
s += ", "
|
|
}
|
|
s += fmt.Sprintf("%s %s", p.cgoType(atype).C, exportParamName(aname, i))
|
|
})
|
|
s += ")"
|
|
|
|
if len(exp.Doc) > 0 {
|
|
fmt.Fprintf(fgcch, "\n%s", exp.Doc)
|
|
if !strings.HasSuffix(exp.Doc, "\n") {
|
|
fmt.Fprint(fgcch, "\n")
|
|
}
|
|
}
|
|
fmt.Fprintf(fgcch, "extern %s;\n", s)
|
|
|
|
fmt.Fprintf(fgcc, "extern void _cgoexp%s_%s(void *);\n", cPrefix, exp.ExpName)
|
|
fmt.Fprintf(fgcc, "\nCGO_NO_SANITIZE_THREAD")
|
|
fmt.Fprintf(fgcc, "\n%s\n", s)
|
|
fmt.Fprintf(fgcc, "{\n")
|
|
fmt.Fprintf(fgcc, "\t__SIZE_TYPE__ _cgo_ctxt = _cgo_wait_runtime_init_done();\n")
|
|
// The results part of the argument structure must be
|
|
// initialized to 0 so the write barriers generated by
|
|
// the assignments to these fields in Go are safe.
|
|
//
|
|
// We use a local static variable to get the zeroed
|
|
// value of the argument type. This avoids including
|
|
// string.h for memset, and is also robust to C++
|
|
// types with constructors. Both GCC and LLVM optimize
|
|
// this into just zeroing _cgo_a.
|
|
fmt.Fprintf(fgcc, "\ttypedef %s %v _cgo_argtype;\n", ctype, p.packedAttribute())
|
|
fmt.Fprintf(fgcc, "\tstatic _cgo_argtype _cgo_zero;\n")
|
|
fmt.Fprintf(fgcc, "\t_cgo_argtype _cgo_a = _cgo_zero;\n")
|
|
if gccResult != "void" && (len(fntype.Results.List) > 1 || len(fntype.Results.List[0].Names) > 1) {
|
|
fmt.Fprintf(fgcc, "\t%s r;\n", gccResult)
|
|
}
|
|
if fn.Recv != nil {
|
|
fmt.Fprintf(fgcc, "\t_cgo_a.recv = recv;\n")
|
|
}
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
fmt.Fprintf(fgcc, "\t_cgo_a.p%d = %s;\n", i, exportParamName(aname, i))
|
|
})
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_release();\n")
|
|
fmt.Fprintf(fgcc, "\tcrosscall2(_cgoexp%s_%s, &_cgo_a, %d, _cgo_ctxt);\n", cPrefix, exp.ExpName, off)
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_acquire();\n")
|
|
fmt.Fprintf(fgcc, "\t_cgo_release_context(_cgo_ctxt);\n")
|
|
if gccResult != "void" {
|
|
if len(fntype.Results.List) == 1 && len(fntype.Results.List[0].Names) <= 1 {
|
|
fmt.Fprintf(fgcc, "\treturn _cgo_a.r0;\n")
|
|
} else {
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
fmt.Fprintf(fgcc, "\tr.r%d = _cgo_a.r%d;\n", i, i)
|
|
})
|
|
fmt.Fprintf(fgcc, "\treturn r;\n")
|
|
}
|
|
}
|
|
fmt.Fprintf(fgcc, "}\n")
|
|
|
|
// In internal linking mode, the Go linker sees both
|
|
// the C wrapper written above and the Go wrapper it
|
|
// references. Hence, export the C wrapper (e.g., for
|
|
// if we're building a shared object). The Go linker
|
|
// will resolve the C wrapper's reference to the Go
|
|
// wrapper without a separate export.
|
|
fmt.Fprintf(fgo2, "//go:cgo_export_dynamic %s\n", exp.ExpName)
|
|
// cgo_export_static refers to a symbol by its linker
|
|
// name, so set the linker name of the Go wrapper.
|
|
fmt.Fprintf(fgo2, "//go:linkname _cgoexp%s_%s _cgoexp%s_%s\n", cPrefix, exp.ExpName, cPrefix, exp.ExpName)
|
|
// In external linking mode, the Go linker sees the Go
|
|
// wrapper, but not the C wrapper. For this case,
|
|
// export the Go wrapper so the host linker can
|
|
// resolve the reference from the C wrapper to the Go
|
|
// wrapper.
|
|
fmt.Fprintf(fgo2, "//go:cgo_export_static _cgoexp%s_%s\n", cPrefix, exp.ExpName)
|
|
|
|
// Build the wrapper function compiled by cmd/compile.
|
|
// This unpacks the argument struct above and calls the Go function.
|
|
fmt.Fprintf(fgo2, "func _cgoexp%s_%s(a *%s) {\n", cPrefix, exp.ExpName, gotype)
|
|
|
|
fmt.Fprintf(fm, "void _cgoexp%s_%s(void* p){}\n", cPrefix, exp.ExpName)
|
|
|
|
fmt.Fprintf(fgo2, "\t")
|
|
|
|
if gccResult != "void" {
|
|
// Write results back to frame.
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 {
|
|
fmt.Fprintf(fgo2, ", ")
|
|
}
|
|
fmt.Fprintf(fgo2, "a.r%d", i)
|
|
})
|
|
fmt.Fprintf(fgo2, " = ")
|
|
}
|
|
if fn.Recv != nil {
|
|
fmt.Fprintf(fgo2, "a.recv.")
|
|
}
|
|
fmt.Fprintf(fgo2, "%s(", exp.Func.Name)
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 {
|
|
fmt.Fprint(fgo2, ", ")
|
|
}
|
|
fmt.Fprintf(fgo2, "a.p%d", i)
|
|
})
|
|
fmt.Fprint(fgo2, ")\n")
|
|
if gccResult != "void" {
|
|
// Verify that any results don't contain any
|
|
// Go pointers.
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if !p.hasPointer(nil, atype, false) {
|
|
return
|
|
}
|
|
fmt.Fprintf(fgo2, "\t_cgoCheckResult(a.r%d)\n", i)
|
|
})
|
|
}
|
|
fmt.Fprint(fgo2, "}\n")
|
|
}
|
|
|
|
fmt.Fprintf(fgcch, "%s", gccExportHeaderEpilog)
|
|
}
|
|
|
|
// Write out the C header allowing C code to call exported gccgo functions.
|
|
func (p *Package) writeGccgoExports(fgo2, fm, fgcc, fgcch io.Writer) {
|
|
gccgoSymbolPrefix := p.gccgoSymbolPrefix()
|
|
|
|
p.writeExportHeader(fgcch)
|
|
|
|
fmt.Fprintf(fgcc, "/* Code generated by cmd/cgo; DO NOT EDIT. */\n\n")
|
|
fmt.Fprintf(fgcc, "#include \"_cgo_export.h\"\n")
|
|
|
|
fmt.Fprintf(fgcc, "%s\n", gccgoExportFileProlog)
|
|
fmt.Fprintf(fgcc, "%s\n", tsanProlog)
|
|
fmt.Fprintf(fgcc, "%s\n", msanProlog)
|
|
|
|
for _, exp := range p.ExpFunc {
|
|
fn := exp.Func
|
|
fntype := fn.Type
|
|
|
|
cdeclBuf := new(bytes.Buffer)
|
|
resultCount := 0
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) { resultCount++ })
|
|
switch resultCount {
|
|
case 0:
|
|
fmt.Fprintf(cdeclBuf, "void")
|
|
case 1:
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
t := p.cgoType(atype)
|
|
fmt.Fprintf(cdeclBuf, "%s", t.C)
|
|
})
|
|
default:
|
|
// Declare a result struct.
|
|
fmt.Fprintf(fgcch, "\n/* Return type for %s */\n", exp.ExpName)
|
|
fmt.Fprintf(fgcch, "struct %s_return {\n", exp.ExpName)
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
t := p.cgoType(atype)
|
|
fmt.Fprintf(fgcch, "\t%s r%d;", t.C, i)
|
|
if len(aname) > 0 {
|
|
fmt.Fprintf(fgcch, " /* %s */", aname)
|
|
}
|
|
fmt.Fprint(fgcch, "\n")
|
|
})
|
|
fmt.Fprintf(fgcch, "};\n")
|
|
fmt.Fprintf(cdeclBuf, "struct %s_return", exp.ExpName)
|
|
}
|
|
|
|
cRet := cdeclBuf.String()
|
|
|
|
cdeclBuf = new(bytes.Buffer)
|
|
fmt.Fprintf(cdeclBuf, "(")
|
|
if fn.Recv != nil {
|
|
fmt.Fprintf(cdeclBuf, "%s recv", p.cgoType(fn.Recv.List[0].Type).C.String())
|
|
}
|
|
// Function parameters.
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 || fn.Recv != nil {
|
|
fmt.Fprintf(cdeclBuf, ", ")
|
|
}
|
|
t := p.cgoType(atype)
|
|
fmt.Fprintf(cdeclBuf, "%s p%d", t.C, i)
|
|
})
|
|
fmt.Fprintf(cdeclBuf, ")")
|
|
cParams := cdeclBuf.String()
|
|
|
|
if len(exp.Doc) > 0 {
|
|
fmt.Fprintf(fgcch, "\n%s", exp.Doc)
|
|
}
|
|
|
|
fmt.Fprintf(fgcch, "extern %s %s%s;\n", cRet, exp.ExpName, cParams)
|
|
|
|
// We need to use a name that will be exported by the
|
|
// Go code; otherwise gccgo will make it static and we
|
|
// will not be able to link against it from the C
|
|
// code.
|
|
goName := "Cgoexp_" + exp.ExpName
|
|
fmt.Fprintf(fgcc, `extern %s %s %s __asm__("%s.%s");`, cRet, goName, cParams, gccgoSymbolPrefix, gccgoToSymbol(goName))
|
|
fmt.Fprint(fgcc, "\n")
|
|
|
|
fmt.Fprint(fgcc, "\nCGO_NO_SANITIZE_THREAD\n")
|
|
fmt.Fprintf(fgcc, "%s %s %s {\n", cRet, exp.ExpName, cParams)
|
|
if resultCount > 0 {
|
|
fmt.Fprintf(fgcc, "\t%s r;\n", cRet)
|
|
}
|
|
fmt.Fprintf(fgcc, "\tif(_cgo_wait_runtime_init_done)\n")
|
|
fmt.Fprintf(fgcc, "\t\t_cgo_wait_runtime_init_done();\n")
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_release();\n")
|
|
fmt.Fprint(fgcc, "\t")
|
|
if resultCount > 0 {
|
|
fmt.Fprint(fgcc, "r = ")
|
|
}
|
|
fmt.Fprintf(fgcc, "%s(", goName)
|
|
if fn.Recv != nil {
|
|
fmt.Fprint(fgcc, "recv")
|
|
}
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 || fn.Recv != nil {
|
|
fmt.Fprintf(fgcc, ", ")
|
|
}
|
|
fmt.Fprintf(fgcc, "p%d", i)
|
|
})
|
|
fmt.Fprint(fgcc, ");\n")
|
|
fmt.Fprintf(fgcc, "\t_cgo_tsan_acquire();\n")
|
|
if resultCount > 0 {
|
|
fmt.Fprint(fgcc, "\treturn r;\n")
|
|
}
|
|
fmt.Fprint(fgcc, "}\n")
|
|
|
|
// Dummy declaration for _cgo_main.c
|
|
fmt.Fprintf(fm, `char %s[1] __asm__("%s.%s");`, goName, gccgoSymbolPrefix, gccgoToSymbol(goName))
|
|
fmt.Fprint(fm, "\n")
|
|
|
|
// For gccgo we use a wrapper function in Go, in order
|
|
// to call CgocallBack and CgocallBackDone.
|
|
|
|
// This code uses printer.Fprint, not conf.Fprint,
|
|
// because we don't want //line comments in the middle
|
|
// of the function types.
|
|
fmt.Fprint(fgo2, "\n")
|
|
fmt.Fprintf(fgo2, "func %s(", goName)
|
|
if fn.Recv != nil {
|
|
fmt.Fprint(fgo2, "recv ")
|
|
printer.Fprint(fgo2, fset, fn.Recv.List[0].Type)
|
|
}
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 || fn.Recv != nil {
|
|
fmt.Fprintf(fgo2, ", ")
|
|
}
|
|
fmt.Fprintf(fgo2, "p%d ", i)
|
|
printer.Fprint(fgo2, fset, atype)
|
|
})
|
|
fmt.Fprintf(fgo2, ")")
|
|
if resultCount > 0 {
|
|
fmt.Fprintf(fgo2, " (")
|
|
forFieldList(fntype.Results,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 {
|
|
fmt.Fprint(fgo2, ", ")
|
|
}
|
|
printer.Fprint(fgo2, fset, atype)
|
|
})
|
|
fmt.Fprint(fgo2, ")")
|
|
}
|
|
fmt.Fprint(fgo2, " {\n")
|
|
fmt.Fprint(fgo2, "\tsyscall.CgocallBack()\n")
|
|
fmt.Fprint(fgo2, "\tdefer syscall.CgocallBackDone()\n")
|
|
fmt.Fprint(fgo2, "\t")
|
|
if resultCount > 0 {
|
|
fmt.Fprint(fgo2, "return ")
|
|
}
|
|
if fn.Recv != nil {
|
|
fmt.Fprint(fgo2, "recv.")
|
|
}
|
|
fmt.Fprintf(fgo2, "%s(", exp.Func.Name)
|
|
forFieldList(fntype.Params,
|
|
func(i int, aname string, atype ast.Expr) {
|
|
if i > 0 {
|
|
fmt.Fprint(fgo2, ", ")
|
|
}
|
|
fmt.Fprintf(fgo2, "p%d", i)
|
|
})
|
|
fmt.Fprint(fgo2, ")\n")
|
|
fmt.Fprint(fgo2, "}\n")
|
|
}
|
|
|
|
fmt.Fprintf(fgcch, "%s", gccExportHeaderEpilog)
|
|
}
|
|
|
|
// writeExportHeader writes out the start of the _cgo_export.h file.
|
|
func (p *Package) writeExportHeader(fgcch io.Writer) {
|
|
fmt.Fprintf(fgcch, "/* Code generated by cmd/cgo; DO NOT EDIT. */\n\n")
|
|
pkg := *importPath
|
|
if pkg == "" {
|
|
pkg = p.PackagePath
|
|
}
|
|
fmt.Fprintf(fgcch, "/* package %s */\n\n", pkg)
|
|
fmt.Fprintf(fgcch, "%s\n", builtinExportProlog)
|
|
|
|
// Remove absolute paths from #line comments in the preamble.
|
|
// They aren't useful for people using the header file,
|
|
// and they mean that the header files change based on the
|
|
// exact location of GOPATH.
|
|
re := regexp.MustCompile(`(?m)^(#line\s+[0-9]+\s+")[^"]*[/\\]([^"]*")`)
|
|
preamble := re.ReplaceAllString(p.Preamble, "$1$2")
|
|
|
|
fmt.Fprintf(fgcch, "/* Start of preamble from import \"C\" comments. */\n\n")
|
|
fmt.Fprintf(fgcch, "%s\n", preamble)
|
|
fmt.Fprintf(fgcch, "\n/* End of preamble from import \"C\" comments. */\n\n")
|
|
|
|
fmt.Fprintf(fgcch, "%s\n", p.gccExportHeaderProlog())
|
|
}
|
|
|
|
// gccgoToSymbol converts a name to a mangled symbol for gccgo.
|
|
func gccgoToSymbol(ppath string) string {
|
|
if gccgoMangler == nil {
|
|
var err error
|
|
cmd := os.Getenv("GCCGO")
|
|
if cmd == "" {
|
|
cmd, err = exec.LookPath("gccgo")
|
|
if err != nil {
|
|
fatalf("unable to locate gccgo: %v", err)
|
|
}
|
|
}
|
|
gccgoMangler, err = pkgpath.ToSymbolFunc(cmd, *objDir)
|
|
if err != nil {
|
|
fatalf("%v", err)
|
|
}
|
|
}
|
|
return gccgoMangler(ppath)
|
|
}
|
|
|
|
// Return the package prefix when using gccgo.
|
|
func (p *Package) gccgoSymbolPrefix() string {
|
|
if !*gccgo {
|
|
return ""
|
|
}
|
|
|
|
if *gccgopkgpath != "" {
|
|
return gccgoToSymbol(*gccgopkgpath)
|
|
}
|
|
if *gccgoprefix == "" && p.PackageName == "main" {
|
|
return "main"
|
|
}
|
|
prefix := gccgoToSymbol(*gccgoprefix)
|
|
if prefix == "" {
|
|
prefix = "go"
|
|
}
|
|
return prefix + "." + p.PackageName
|
|
}
|
|
|
|
// Call a function for each entry in an ast.FieldList, passing the
|
|
// index into the list, the name if any, and the type.
|
|
func forFieldList(fl *ast.FieldList, fn func(int, string, ast.Expr)) {
|
|
if fl == nil {
|
|
return
|
|
}
|
|
i := 0
|
|
for _, r := range fl.List {
|
|
if r.Names == nil {
|
|
fn(i, "", r.Type)
|
|
i++
|
|
} else {
|
|
for _, n := range r.Names {
|
|
fn(i, n.Name, r.Type)
|
|
i++
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
func c(repr string, args ...interface{}) *TypeRepr {
|
|
return &TypeRepr{repr, args}
|
|
}
|
|
|
|
// Map predeclared Go types to Type.
|
|
var goTypes = map[string]*Type{
|
|
"bool": {Size: 1, Align: 1, C: c("GoUint8")},
|
|
"byte": {Size: 1, Align: 1, C: c("GoUint8")},
|
|
"int": {Size: 0, Align: 0, C: c("GoInt")},
|
|
"uint": {Size: 0, Align: 0, C: c("GoUint")},
|
|
"rune": {Size: 4, Align: 4, C: c("GoInt32")},
|
|
"int8": {Size: 1, Align: 1, C: c("GoInt8")},
|
|
"uint8": {Size: 1, Align: 1, C: c("GoUint8")},
|
|
"int16": {Size: 2, Align: 2, C: c("GoInt16")},
|
|
"uint16": {Size: 2, Align: 2, C: c("GoUint16")},
|
|
"int32": {Size: 4, Align: 4, C: c("GoInt32")},
|
|
"uint32": {Size: 4, Align: 4, C: c("GoUint32")},
|
|
"int64": {Size: 8, Align: 8, C: c("GoInt64")},
|
|
"uint64": {Size: 8, Align: 8, C: c("GoUint64")},
|
|
"float32": {Size: 4, Align: 4, C: c("GoFloat32")},
|
|
"float64": {Size: 8, Align: 8, C: c("GoFloat64")},
|
|
"complex64": {Size: 8, Align: 4, C: c("GoComplex64")},
|
|
"complex128": {Size: 16, Align: 8, C: c("GoComplex128")},
|
|
}
|
|
|
|
// Map an ast type to a Type.
|
|
func (p *Package) cgoType(e ast.Expr) *Type {
|
|
switch t := e.(type) {
|
|
case *ast.StarExpr:
|
|
x := p.cgoType(t.X)
|
|
return &Type{Size: p.PtrSize, Align: p.PtrSize, C: c("%s*", x.C)}
|
|
case *ast.ArrayType:
|
|
if t.Len == nil {
|
|
// Slice: pointer, len, cap.
|
|
return &Type{Size: p.PtrSize * 3, Align: p.PtrSize, C: c("GoSlice")}
|
|
}
|
|
// Non-slice array types are not supported.
|
|
case *ast.StructType:
|
|
// Not supported.
|
|
case *ast.FuncType:
|
|
return &Type{Size: p.PtrSize, Align: p.PtrSize, C: c("void*")}
|
|
case *ast.InterfaceType:
|
|
return &Type{Size: 2 * p.PtrSize, Align: p.PtrSize, C: c("GoInterface")}
|
|
case *ast.MapType:
|
|
return &Type{Size: p.PtrSize, Align: p.PtrSize, C: c("GoMap")}
|
|
case *ast.ChanType:
|
|
return &Type{Size: p.PtrSize, Align: p.PtrSize, C: c("GoChan")}
|
|
case *ast.Ident:
|
|
// Look up the type in the top level declarations.
|
|
// TODO: Handle types defined within a function.
|
|
for _, d := range p.Decl {
|
|
gd, ok := d.(*ast.GenDecl)
|
|
if !ok || gd.Tok != token.TYPE {
|
|
continue
|
|
}
|
|
for _, spec := range gd.Specs {
|
|
ts, ok := spec.(*ast.TypeSpec)
|
|
if !ok {
|
|
continue
|
|
}
|
|
if ts.Name.Name == t.Name {
|
|
return p.cgoType(ts.Type)
|
|
}
|
|
}
|
|
}
|
|
if def := typedef[t.Name]; def != nil {
|
|
return def
|
|
}
|
|
if t.Name == "uintptr" {
|
|
return &Type{Size: p.PtrSize, Align: p.PtrSize, C: c("GoUintptr")}
|
|
}
|
|
if t.Name == "string" {
|
|
// The string data is 1 pointer + 1 (pointer-sized) int.
|
|
return &Type{Size: 2 * p.PtrSize, Align: p.PtrSize, C: c("GoString")}
|
|
}
|
|
if t.Name == "error" {
|
|
return &Type{Size: 2 * p.PtrSize, Align: p.PtrSize, C: c("GoInterface")}
|
|
}
|
|
if r, ok := goTypes[t.Name]; ok {
|
|
if r.Size == 0 { // int or uint
|
|
rr := new(Type)
|
|
*rr = *r
|
|
rr.Size = p.IntSize
|
|
rr.Align = p.IntSize
|
|
r = rr
|
|
}
|
|
if r.Align > p.PtrSize {
|
|
r.Align = p.PtrSize
|
|
}
|
|
return r
|
|
}
|
|
error_(e.Pos(), "unrecognized Go type %s", t.Name)
|
|
return &Type{Size: 4, Align: 4, C: c("int")}
|
|
case *ast.SelectorExpr:
|
|
id, ok := t.X.(*ast.Ident)
|
|
if ok && id.Name == "unsafe" && t.Sel.Name == "Pointer" {
|
|
return &Type{Size: p.PtrSize, Align: p.PtrSize, C: c("void*")}
|
|
}
|
|
}
|
|
error_(e.Pos(), "Go type not supported in export: %s", gofmt(e))
|
|
return &Type{Size: 4, Align: 4, C: c("int")}
|
|
}
|
|
|
|
const gccProlog = `
|
|
#line 1 "cgo-gcc-prolog"
|
|
/*
|
|
If x and y are not equal, the type will be invalid
|
|
(have a negative array count) and an inscrutable error will come
|
|
out of the compiler and hopefully mention "name".
|
|
*/
|
|
#define __cgo_compile_assert_eq(x, y, name) typedef char name[(x-y)*(x-y)*-2UL+1UL];
|
|
|
|
/* Check at compile time that the sizes we use match our expectations. */
|
|
#define __cgo_size_assert(t, n) __cgo_compile_assert_eq(sizeof(t), (size_t)n, _cgo_sizeof_##t##_is_not_##n)
|
|
|
|
__cgo_size_assert(char, 1)
|
|
__cgo_size_assert(short, 2)
|
|
__cgo_size_assert(int, 4)
|
|
typedef long long __cgo_long_long;
|
|
__cgo_size_assert(__cgo_long_long, 8)
|
|
__cgo_size_assert(float, 4)
|
|
__cgo_size_assert(double, 8)
|
|
|
|
extern char* _cgo_topofstack(void);
|
|
|
|
/*
|
|
We use packed structs, but they are always aligned.
|
|
The pragmas and address-of-packed-member are only recognized as warning
|
|
groups in clang 4.0+, so ignore unknown pragmas first.
|
|
*/
|
|
#pragma GCC diagnostic ignored "-Wunknown-pragmas"
|
|
#pragma GCC diagnostic ignored "-Wpragmas"
|
|
#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
|
|
|
|
#include <errno.h>
|
|
#include <string.h>
|
|
`
|
|
|
|
// Prologue defining TSAN functions in C.
|
|
const noTsanProlog = `
|
|
#define CGO_NO_SANITIZE_THREAD
|
|
#define _cgo_tsan_acquire()
|
|
#define _cgo_tsan_release()
|
|
`
|
|
|
|
// This must match the TSAN code in runtime/cgo/libcgo.h.
|
|
// This is used when the code is built with the C/C++ Thread SANitizer,
|
|
// which is not the same as the Go race detector.
|
|
// __tsan_acquire tells TSAN that we are acquiring a lock on a variable,
|
|
// in this case _cgo_sync. __tsan_release releases the lock.
|
|
// (There is no actual lock, we are just telling TSAN that there is.)
|
|
//
|
|
// When we call from Go to C we call _cgo_tsan_acquire.
|
|
// When the C function returns we call _cgo_tsan_release.
|
|
// Similarly, when C calls back into Go we call _cgo_tsan_release
|
|
// and then call _cgo_tsan_acquire when we return to C.
|
|
// These calls tell TSAN that there is a serialization point at the C call.
|
|
//
|
|
// This is necessary because TSAN, which is a C/C++ tool, can not see
|
|
// the synchronization in the Go code. Without these calls, when
|
|
// multiple goroutines call into C code, TSAN does not understand
|
|
// that the calls are properly synchronized on the Go side.
|
|
//
|
|
// To be clear, if the calls are not properly synchronized on the Go side,
|
|
// we will be hiding races. But when using TSAN on mixed Go C/C++ code
|
|
// it is more important to avoid false positives, which reduce confidence
|
|
// in the tool, than to avoid false negatives.
|
|
const yesTsanProlog = `
|
|
#line 1 "cgo-tsan-prolog"
|
|
#define CGO_NO_SANITIZE_THREAD __attribute__ ((no_sanitize_thread))
|
|
|
|
long long _cgo_sync __attribute__ ((common));
|
|
|
|
extern void __tsan_acquire(void*);
|
|
extern void __tsan_release(void*);
|
|
|
|
__attribute__ ((unused))
|
|
static void _cgo_tsan_acquire() {
|
|
__tsan_acquire(&_cgo_sync);
|
|
}
|
|
|
|
__attribute__ ((unused))
|
|
static void _cgo_tsan_release() {
|
|
__tsan_release(&_cgo_sync);
|
|
}
|
|
`
|
|
|
|
// Set to yesTsanProlog if we see -fsanitize=thread in the flags for gcc.
|
|
var tsanProlog = noTsanProlog
|
|
|
|
// noMsanProlog is a prologue defining an MSAN function in C.
|
|
// This is used when not compiling with -fsanitize=memory.
|
|
const noMsanProlog = `
|
|
#define _cgo_msan_write(addr, sz)
|
|
`
|
|
|
|
// yesMsanProlog is a prologue defining an MSAN function in C.
|
|
// This is used when compiling with -fsanitize=memory.
|
|
// See the comment above where _cgo_msan_write is called.
|
|
const yesMsanProlog = `
|
|
extern void __msan_unpoison(const volatile void *, size_t);
|
|
|
|
#define _cgo_msan_write(addr, sz) __msan_unpoison((addr), (sz))
|
|
`
|
|
|
|
// msanProlog is set to yesMsanProlog if we see -fsanitize=memory in the flags
|
|
// for the C compiler.
|
|
var msanProlog = noMsanProlog
|
|
|
|
const builtinProlog = `
|
|
#line 1 "cgo-builtin-prolog"
|
|
#include <stddef.h> /* for ptrdiff_t and size_t below */
|
|
|
|
/* Define intgo when compiling with GCC. */
|
|
typedef ptrdiff_t intgo;
|
|
|
|
#define GO_CGO_GOSTRING_TYPEDEF
|
|
typedef struct { const char *p; intgo n; } _GoString_;
|
|
typedef struct { char *p; intgo n; intgo c; } _GoBytes_;
|
|
_GoString_ GoString(char *p);
|
|
_GoString_ GoStringN(char *p, int l);
|
|
_GoBytes_ GoBytes(void *p, int n);
|
|
char *CString(_GoString_);
|
|
void *CBytes(_GoBytes_);
|
|
void *_CMalloc(size_t);
|
|
|
|
__attribute__ ((unused))
|
|
static size_t _GoStringLen(_GoString_ s) { return (size_t)s.n; }
|
|
|
|
__attribute__ ((unused))
|
|
static const char *_GoStringPtr(_GoString_ s) { return s.p; }
|
|
`
|
|
|
|
const goProlog = `
|
|
//go:linkname _cgo_runtime_cgocall runtime.cgocall
|
|
func _cgo_runtime_cgocall(unsafe.Pointer, uintptr) int32
|
|
|
|
//go:linkname _cgoCheckPointer runtime.cgoCheckPointer
|
|
func _cgoCheckPointer(interface{}, interface{})
|
|
|
|
//go:linkname _cgoCheckResult runtime.cgoCheckResult
|
|
func _cgoCheckResult(interface{})
|
|
`
|
|
|
|
const gccgoGoProlog = `
|
|
func _cgoCheckPointer(interface{}, interface{})
|
|
|
|
func _cgoCheckResult(interface{})
|
|
`
|
|
|
|
const goStringDef = `
|
|
//go:linkname _cgo_runtime_gostring runtime.gostring
|
|
func _cgo_runtime_gostring(*_Ctype_char) string
|
|
|
|
func _Cfunc_GoString(p *_Ctype_char) string {
|
|
return _cgo_runtime_gostring(p)
|
|
}
|
|
`
|
|
|
|
const goStringNDef = `
|
|
//go:linkname _cgo_runtime_gostringn runtime.gostringn
|
|
func _cgo_runtime_gostringn(*_Ctype_char, int) string
|
|
|
|
func _Cfunc_GoStringN(p *_Ctype_char, l _Ctype_int) string {
|
|
return _cgo_runtime_gostringn(p, int(l))
|
|
}
|
|
`
|
|
|
|
const goBytesDef = `
|
|
//go:linkname _cgo_runtime_gobytes runtime.gobytes
|
|
func _cgo_runtime_gobytes(unsafe.Pointer, int) []byte
|
|
|
|
func _Cfunc_GoBytes(p unsafe.Pointer, l _Ctype_int) []byte {
|
|
return _cgo_runtime_gobytes(p, int(l))
|
|
}
|
|
`
|
|
|
|
const cStringDef = `
|
|
func _Cfunc_CString(s string) *_Ctype_char {
|
|
p := _cgo_cmalloc(uint64(len(s)+1))
|
|
pp := (*[1<<30]byte)(p)
|
|
copy(pp[:], s)
|
|
pp[len(s)] = 0
|
|
return (*_Ctype_char)(p)
|
|
}
|
|
`
|
|
|
|
const cBytesDef = `
|
|
func _Cfunc_CBytes(b []byte) unsafe.Pointer {
|
|
p := _cgo_cmalloc(uint64(len(b)))
|
|
pp := (*[1<<30]byte)(p)
|
|
copy(pp[:], b)
|
|
return p
|
|
}
|
|
`
|
|
|
|
const cMallocDef = `
|
|
func _Cfunc__CMalloc(n _Ctype_size_t) unsafe.Pointer {
|
|
return _cgo_cmalloc(uint64(n))
|
|
}
|
|
`
|
|
|
|
var builtinDefs = map[string]string{
|
|
"GoString": goStringDef,
|
|
"GoStringN": goStringNDef,
|
|
"GoBytes": goBytesDef,
|
|
"CString": cStringDef,
|
|
"CBytes": cBytesDef,
|
|
"_CMalloc": cMallocDef,
|
|
}
|
|
|
|
// Definitions for C.malloc in Go and in C. We define it ourselves
|
|
// since we call it from functions we define, such as C.CString.
|
|
// Also, we have historically ensured that C.malloc does not return
|
|
// nil even for an allocation of 0.
|
|
|
|
const cMallocDefGo = `
|
|
//go:cgo_import_static _cgoPREFIX_Cfunc__Cmalloc
|
|
//go:linkname __cgofn__cgoPREFIX_Cfunc__Cmalloc _cgoPREFIX_Cfunc__Cmalloc
|
|
var __cgofn__cgoPREFIX_Cfunc__Cmalloc byte
|
|
var _cgoPREFIX_Cfunc__Cmalloc = unsafe.Pointer(&__cgofn__cgoPREFIX_Cfunc__Cmalloc)
|
|
|
|
//go:linkname runtime_throw runtime.throw
|
|
func runtime_throw(string)
|
|
|
|
//go:cgo_unsafe_args
|
|
func _cgo_cmalloc(p0 uint64) (r1 unsafe.Pointer) {
|
|
_cgo_runtime_cgocall(_cgoPREFIX_Cfunc__Cmalloc, uintptr(unsafe.Pointer(&p0)))
|
|
if r1 == nil {
|
|
runtime_throw("runtime: C malloc failed")
|
|
}
|
|
return
|
|
}
|
|
`
|
|
|
|
// cMallocDefC defines the C version of C.malloc for the gc compiler.
|
|
// It is defined here because C.CString and friends need a definition.
|
|
// We define it by hand, rather than simply inventing a reference to
|
|
// C.malloc, because <stdlib.h> may not have been included.
|
|
// This is approximately what writeOutputFunc would generate, but
|
|
// skips the cgo_topofstack code (which is only needed if the C code
|
|
// calls back into Go). This also avoids returning nil for an
|
|
// allocation of 0 bytes.
|
|
const cMallocDefC = `
|
|
CGO_NO_SANITIZE_THREAD
|
|
void _cgoPREFIX_Cfunc__Cmalloc(void *v) {
|
|
struct {
|
|
unsigned long long p0;
|
|
void *r1;
|
|
} PACKED *a = v;
|
|
void *ret;
|
|
_cgo_tsan_acquire();
|
|
ret = malloc(a->p0);
|
|
if (ret == 0 && a->p0 == 0) {
|
|
ret = malloc(1);
|
|
}
|
|
a->r1 = ret;
|
|
_cgo_tsan_release();
|
|
}
|
|
`
|
|
|
|
func (p *Package) cPrologGccgo() string {
|
|
r := strings.NewReplacer(
|
|
"PREFIX", cPrefix,
|
|
"GCCGOSYMBOLPREF", p.gccgoSymbolPrefix(),
|
|
"_cgoCheckPointer", gccgoToSymbol("_cgoCheckPointer"),
|
|
"_cgoCheckResult", gccgoToSymbol("_cgoCheckResult"))
|
|
return r.Replace(cPrologGccgo)
|
|
}
|
|
|
|
const cPrologGccgo = `
|
|
#line 1 "cgo-c-prolog-gccgo"
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
typedef unsigned char byte;
|
|
typedef intptr_t intgo;
|
|
|
|
struct __go_string {
|
|
const unsigned char *__data;
|
|
intgo __length;
|
|
};
|
|
|
|
typedef struct __go_open_array {
|
|
void* __values;
|
|
intgo __count;
|
|
intgo __capacity;
|
|
} Slice;
|
|
|
|
struct __go_string __go_byte_array_to_string(const void* p, intgo len);
|
|
struct __go_open_array __go_string_to_byte_array (struct __go_string str);
|
|
|
|
extern void runtime_throw(const char *);
|
|
|
|
const char *_cgoPREFIX_Cfunc_CString(struct __go_string s) {
|
|
char *p = malloc(s.__length+1);
|
|
if(p == NULL)
|
|
runtime_throw("runtime: C malloc failed");
|
|
memmove(p, s.__data, s.__length);
|
|
p[s.__length] = 0;
|
|
return p;
|
|
}
|
|
|
|
void *_cgoPREFIX_Cfunc_CBytes(struct __go_open_array b) {
|
|
char *p = malloc(b.__count);
|
|
if(p == NULL)
|
|
runtime_throw("runtime: C malloc failed");
|
|
memmove(p, b.__values, b.__count);
|
|
return p;
|
|
}
|
|
|
|
struct __go_string _cgoPREFIX_Cfunc_GoString(char *p) {
|
|
intgo len = (p != NULL) ? strlen(p) : 0;
|
|
return __go_byte_array_to_string(p, len);
|
|
}
|
|
|
|
struct __go_string _cgoPREFIX_Cfunc_GoStringN(char *p, int32_t n) {
|
|
return __go_byte_array_to_string(p, n);
|
|
}
|
|
|
|
Slice _cgoPREFIX_Cfunc_GoBytes(char *p, int32_t n) {
|
|
struct __go_string s = { (const unsigned char *)p, n };
|
|
return __go_string_to_byte_array(s);
|
|
}
|
|
|
|
void *_cgoPREFIX_Cfunc__CMalloc(size_t n) {
|
|
void *p = malloc(n);
|
|
if(p == NULL && n == 0)
|
|
p = malloc(1);
|
|
if(p == NULL)
|
|
runtime_throw("runtime: C malloc failed");
|
|
return p;
|
|
}
|
|
|
|
struct __go_type_descriptor;
|
|
typedef struct __go_empty_interface {
|
|
const struct __go_type_descriptor *__type_descriptor;
|
|
void *__object;
|
|
} Eface;
|
|
|
|
extern void runtimeCgoCheckPointer(Eface, Eface)
|
|
__asm__("runtime.cgoCheckPointer")
|
|
__attribute__((weak));
|
|
|
|
extern void localCgoCheckPointer(Eface, Eface)
|
|
__asm__("GCCGOSYMBOLPREF._cgoCheckPointer");
|
|
|
|
void localCgoCheckPointer(Eface ptr, Eface arg) {
|
|
if(runtimeCgoCheckPointer) {
|
|
runtimeCgoCheckPointer(ptr, arg);
|
|
}
|
|
}
|
|
|
|
extern void runtimeCgoCheckResult(Eface)
|
|
__asm__("runtime.cgoCheckResult")
|
|
__attribute__((weak));
|
|
|
|
extern void localCgoCheckResult(Eface)
|
|
__asm__("GCCGOSYMBOLPREF._cgoCheckResult");
|
|
|
|
void localCgoCheckResult(Eface val) {
|
|
if(runtimeCgoCheckResult) {
|
|
runtimeCgoCheckResult(val);
|
|
}
|
|
}
|
|
`
|
|
|
|
// builtinExportProlog is a shorter version of builtinProlog,
|
|
// to be put into the _cgo_export.h file.
|
|
// For historical reasons we can't use builtinProlog in _cgo_export.h,
|
|
// because _cgo_export.h defines GoString as a struct while builtinProlog
|
|
// defines it as a function. We don't change this to avoid unnecessarily
|
|
// breaking existing code.
|
|
// The test of GO_CGO_GOSTRING_TYPEDEF avoids a duplicate definition
|
|
// error if a Go file with a cgo comment #include's the export header
|
|
// generated by a different package.
|
|
const builtinExportProlog = `
|
|
#line 1 "cgo-builtin-export-prolog"
|
|
|
|
#include <stddef.h> /* for ptrdiff_t below */
|
|
|
|
#ifndef GO_CGO_EXPORT_PROLOGUE_H
|
|
#define GO_CGO_EXPORT_PROLOGUE_H
|
|
|
|
#ifndef GO_CGO_GOSTRING_TYPEDEF
|
|
typedef struct { const char *p; ptrdiff_t n; } _GoString_;
|
|
#endif
|
|
|
|
#endif
|
|
`
|
|
|
|
func (p *Package) gccExportHeaderProlog() string {
|
|
return strings.Replace(gccExportHeaderProlog, "GOINTBITS", fmt.Sprint(8*p.IntSize), -1)
|
|
}
|
|
|
|
// gccExportHeaderProlog is written to the exported header, after the
|
|
// import "C" comment preamble but before the generated declarations
|
|
// of exported functions. This permits the generated declarations to
|
|
// use the type names that appear in goTypes, above.
|
|
//
|
|
// The test of GO_CGO_GOSTRING_TYPEDEF avoids a duplicate definition
|
|
// error if a Go file with a cgo comment #include's the export header
|
|
// generated by a different package. Unfortunately GoString means two
|
|
// different things: in this prolog it means a C name for the Go type,
|
|
// while in the prolog written into the start of the C code generated
|
|
// from a cgo-using Go file it means the C.GoString function. There is
|
|
// no way to resolve this conflict, but it also doesn't make much
|
|
// difference, as Go code never wants to refer to the latter meaning.
|
|
const gccExportHeaderProlog = `
|
|
/* Start of boilerplate cgo prologue. */
|
|
#line 1 "cgo-gcc-export-header-prolog"
|
|
|
|
#ifndef GO_CGO_PROLOGUE_H
|
|
#define GO_CGO_PROLOGUE_H
|
|
|
|
typedef signed char GoInt8;
|
|
typedef unsigned char GoUint8;
|
|
typedef short GoInt16;
|
|
typedef unsigned short GoUint16;
|
|
typedef int GoInt32;
|
|
typedef unsigned int GoUint32;
|
|
typedef long long GoInt64;
|
|
typedef unsigned long long GoUint64;
|
|
typedef GoIntGOINTBITS GoInt;
|
|
typedef GoUintGOINTBITS GoUint;
|
|
typedef __SIZE_TYPE__ GoUintptr;
|
|
typedef float GoFloat32;
|
|
typedef double GoFloat64;
|
|
typedef float _Complex GoComplex64;
|
|
typedef double _Complex GoComplex128;
|
|
|
|
/*
|
|
static assertion to make sure the file is being used on architecture
|
|
at least with matching size of GoInt.
|
|
*/
|
|
typedef char _check_for_GOINTBITS_bit_pointer_matching_GoInt[sizeof(void*)==GOINTBITS/8 ? 1:-1];
|
|
|
|
#ifndef GO_CGO_GOSTRING_TYPEDEF
|
|
typedef _GoString_ GoString;
|
|
#endif
|
|
typedef void *GoMap;
|
|
typedef void *GoChan;
|
|
typedef struct { void *t; void *v; } GoInterface;
|
|
typedef struct { void *data; GoInt len; GoInt cap; } GoSlice;
|
|
|
|
#endif
|
|
|
|
/* End of boilerplate cgo prologue. */
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
`
|
|
|
|
// gccExportHeaderEpilog goes at the end of the generated header file.
|
|
const gccExportHeaderEpilog = `
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
`
|
|
|
|
// gccgoExportFileProlog is written to the _cgo_export.c file when
|
|
// using gccgo.
|
|
// We use weak declarations, and test the addresses, so that this code
|
|
// works with older versions of gccgo.
|
|
const gccgoExportFileProlog = `
|
|
#line 1 "cgo-gccgo-export-file-prolog"
|
|
extern _Bool runtime_iscgo __attribute__ ((weak));
|
|
|
|
static void GoInit(void) __attribute__ ((constructor));
|
|
static void GoInit(void) {
|
|
if(&runtime_iscgo)
|
|
runtime_iscgo = 1;
|
|
}
|
|
|
|
extern __SIZE_TYPE__ _cgo_wait_runtime_init_done(void) __attribute__ ((weak));
|
|
`
|