haven/nexgb/help.go
Přemysl Janouch 48fb710f35
nexgb: post-merge fixups and cleanups
AUTHORS, CONTRIBUTORS: still useful, add people from git log, clean up.

LICENSE: Google doesn't really grant you shit anymore.  The EU doesn't
have software patents either, so it doesn't affect me directly.

README, doc.go: erase mentions of unmaintained xgbutil.
2018-09-08 19:51:53 +02:00

106 lines
2.6 KiB
Go

package nexgb
/*
help.go is meant to contain a rough hodge podge of functions that are mainly
used in the auto generated code. Indeed, several functions here are simple
wrappers so that the sub-packages don't need to be smart about which stdlib
packages to import.
Also, the 'Get..' and 'Put..' functions are used through the core xgb package
too. (xgbutil uses them too.)
*/
import (
"fmt"
"strings"
)
// StringsJoin is an alias to strings.Join. It allows us to avoid having to
// import 'strings' in each of the generated Go files.
func StringsJoin(ss []string, sep string) string {
return strings.Join(ss, sep)
}
// Sprintf is so we don't need to import 'fmt' in the generated Go files.
func Sprintf(format string, v ...interface{}) string {
return fmt.Sprintf(format, v...)
}
// Errorf is just a wrapper for fmt.Errorf. Exists for the same reason
// that 'stringsJoin' and 'sprintf' exists.
func Errorf(format string, v ...interface{}) error {
return fmt.Errorf(format, v...)
}
// Pad a length to align on 4 bytes.
func Pad(n int) int {
return (n + 3) & ^3
}
// PopCount counts the number of bits set in a value list mask.
func PopCount(mask0 int) int {
mask := uint32(mask0)
n := 0
for i := uint32(0); i < 32; i++ {
if mask&(1<<i) != 0 {
n++
}
}
return n
}
// Put16 takes a 16 bit integer and copies it into a byte slice.
func Put16(buf []byte, v uint16) {
buf[0] = byte(v)
buf[1] = byte(v >> 8)
}
// Put32 takes a 32 bit integer and copies it into a byte slice.
func Put32(buf []byte, v uint32) {
buf[0] = byte(v)
buf[1] = byte(v >> 8)
buf[2] = byte(v >> 16)
buf[3] = byte(v >> 24)
}
// Put64 takes a 64 bit integer and copies it into a byte slice.
func Put64(buf []byte, v uint64) {
buf[0] = byte(v)
buf[1] = byte(v >> 8)
buf[2] = byte(v >> 16)
buf[3] = byte(v >> 24)
buf[4] = byte(v >> 32)
buf[5] = byte(v >> 40)
buf[6] = byte(v >> 48)
buf[7] = byte(v >> 56)
}
// Get16 constructs a 16 bit integer from the beginning of a byte slice.
func Get16(buf []byte) uint16 {
v := uint16(buf[0])
v |= uint16(buf[1]) << 8
return v
}
// Get32 constructs a 32 bit integer from the beginning of a byte slice.
func Get32(buf []byte) uint32 {
v := uint32(buf[0])
v |= uint32(buf[1]) << 8
v |= uint32(buf[2]) << 16
v |= uint32(buf[3]) << 24
return v
}
// Get64 constructs a 64 bit integer from the beginning of a byte slice.
func Get64(buf []byte) uint64 {
v := uint64(buf[0])
v |= uint64(buf[1]) << 8
v |= uint64(buf[2]) << 16
v |= uint64(buf[3]) << 24
v |= uint64(buf[4]) << 32
v |= uint64(buf[5]) << 40
v |= uint64(buf[6]) << 48
v |= uint64(buf[7]) << 56
return v
}