diff options
Diffstat (limited to 'src/pkg/syscall/syscall_unix.go')
-rw-r--r-- | src/pkg/syscall/syscall_unix.go | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/src/pkg/syscall/syscall_unix.go b/src/pkg/syscall/syscall_unix.go new file mode 100644 index 000000000..c298b91b4 --- /dev/null +++ b/src/pkg/syscall/syscall_unix.go @@ -0,0 +1,90 @@ +// Copyright 2009 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 syscall + +import ( + "sync" + "unsafe" +) + +var ( + Stdin = 0 + Stdout = 1 + Stderr = 2 +) + +const darwinAMD64 = OS == "darwin" && ARCH == "amd64" + +func Syscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr) +func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) +func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr) +func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr) + +func Errstr(errno int) string { + if errno < 0 || errno >= int(len(errors)) { + return "error " + itoa(errno) + } + return errors[errno] +} + +// Mmap manager, for use by operating system-specific implementations. + +type mmapper struct { + sync.Mutex + active map[*byte][]byte // active mappings; key is last byte in mapping + mmap func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, int) + munmap func(addr uintptr, length uintptr) int +} + +func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, errno int) { + if length <= 0 { + return nil, EINVAL + } + + // Map the requested memory. + addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset) + if errno != 0 { + return nil, errno + } + + // Slice memory layout + var sl = struct { + addr uintptr + len int + cap int + }{addr, length, length} + + // Use unsafe to turn sl into a []byte. + b := *(*[]byte)(unsafe.Pointer(&sl)) + + // Register mapping in m and return it. + p := &b[cap(b)-1] + m.Lock() + defer m.Unlock() + m.active[p] = b + return b, 0 +} + +func (m *mmapper) Munmap(data []byte) (errno int) { + if len(data) == 0 || len(data) != cap(data) { + return EINVAL + } + + // Find the base of the mapping. + p := &data[cap(data)-1] + m.Lock() + defer m.Unlock() + b := m.active[p] + if b == nil || &b[0] != &data[0] { + return EINVAL + } + + // Unmap the memory and update m. + if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != 0 { + return errno + } + m.active[p] = nil, false + return 0 +} |