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