github.com/jgarto/itcv@v0.0.0-20180826224514-4eea09c1aa0d/_vendor/src/golang.org/x/sys/plan9/syscall.go (about)

     1  // Copyright 2009 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build plan9
     6  
     7  // Package plan9 contains an interface to the low-level operating system
     8  // primitives.  OS details vary depending on the underlying system, and
     9  // by default, godoc will display the OS-specific documentation for the current
    10  // system.  If you want godoc to display documentation for another
    11  // system, set $GOOS and $GOARCH to the desired system.  For example, if
    12  // you want to view documentation for freebsd/arm on linux/amd64, set $GOOS
    13  // to freebsd and $GOARCH to arm.
    14  // The primary use of this package is inside other packages that provide a more
    15  // portable interface to the system, such as "os", "time" and "net".  Use
    16  // those packages rather than this one if you can.
    17  // For details of the functions and data types in this package consult
    18  // the manuals for the appropriate operating system.
    19  // These calls return err == nil to indicate success; otherwise
    20  // err represents an operating system error describing the failure and
    21  // holds a value of type syscall.ErrorString.
    22  package plan9 // import "golang.org/x/sys/plan9"
    23  
    24  import "unsafe"
    25  
    26  // ByteSliceFromString returns a NUL-terminated slice of bytes
    27  // containing the text of s. If s contains a NUL byte at any
    28  // location, it returns (nil, EINVAL).
    29  func ByteSliceFromString(s string) ([]byte, error) {
    30  	for i := 0; i < len(s); i++ {
    31  		if s[i] == 0 {
    32  			return nil, EINVAL
    33  		}
    34  	}
    35  	a := make([]byte, len(s)+1)
    36  	copy(a, s)
    37  	return a, nil
    38  }
    39  
    40  // BytePtrFromString returns a pointer to a NUL-terminated array of
    41  // bytes containing the text of s. If s contains a NUL byte at any
    42  // location, it returns (nil, EINVAL).
    43  func BytePtrFromString(s string) (*byte, error) {
    44  	a, err := ByteSliceFromString(s)
    45  	if err != nil {
    46  		return nil, err
    47  	}
    48  	return &a[0], nil
    49  }
    50  
    51  // Single-word zero for use when we need a valid pointer to 0 bytes.
    52  // See mksyscall.pl.
    53  var _zero uintptr
    54  
    55  func (ts *Timespec) Unix() (sec int64, nsec int64) {
    56  	return int64(ts.Sec), int64(ts.Nsec)
    57  }
    58  
    59  func (tv *Timeval) Unix() (sec int64, nsec int64) {
    60  	return int64(tv.Sec), int64(tv.Usec) * 1000
    61  }
    62  
    63  func (ts *Timespec) Nano() int64 {
    64  	return int64(ts.Sec)*1e9 + int64(ts.Nsec)
    65  }
    66  
    67  func (tv *Timeval) Nano() int64 {
    68  	return int64(tv.Sec)*1e9 + int64(tv.Usec)*1000
    69  }
    70  
    71  // use is a no-op, but the compiler cannot see that it is.
    72  // Calling use(p) ensures that p is kept live until that point.
    73  //go:noescape
    74  func use(p unsafe.Pointer)