well-goknown/vendor/github.com/nbd-wtf/go-nostr/helpers.go
2024-10-28 20:11:29 -04:00

115 lines
2.5 KiB
Go

package nostr
import (
"strconv"
"strings"
"sync"
"unsafe"
"golang.org/x/exp/constraints"
)
const MAX_LOCKS = 50
var namedMutexPool = make([]sync.Mutex, MAX_LOCKS)
//go:noescape
//go:linkname memhash runtime.memhash
func memhash(p unsafe.Pointer, h, s uintptr) uintptr
func namedLock(name string) (unlock func()) {
sptr := unsafe.StringData(name)
idx := uint64(memhash(unsafe.Pointer(sptr), 0, uintptr(len(name)))) % MAX_LOCKS
namedMutexPool[idx].Lock()
return namedMutexPool[idx].Unlock
}
func similar[E constraints.Ordered](as, bs []E) bool {
if len(as) != len(bs) {
return false
}
for _, a := range as {
for _, b := range bs {
if b == a {
goto next
}
}
// didn't find a B that corresponded to the current A
return false
next:
continue
}
return true
}
// Escaping strings for JSON encoding according to RFC8259.
// Also encloses result in quotation marks "".
func escapeString(dst []byte, s string) []byte {
dst = append(dst, '"')
for i := 0; i < len(s); i++ {
c := s[i]
switch {
case c == '"':
// quotation mark
dst = append(dst, []byte{'\\', '"'}...)
case c == '\\':
// reverse solidus
dst = append(dst, []byte{'\\', '\\'}...)
case c >= 0x20:
// default, rest below are control chars
dst = append(dst, c)
case c == 0x08:
dst = append(dst, []byte{'\\', 'b'}...)
case c < 0x09:
dst = append(dst, []byte{'\\', 'u', '0', '0', '0', '0' + c}...)
case c == 0x09:
dst = append(dst, []byte{'\\', 't'}...)
case c == 0x0a:
dst = append(dst, []byte{'\\', 'n'}...)
case c == 0x0c:
dst = append(dst, []byte{'\\', 'f'}...)
case c == 0x0d:
dst = append(dst, []byte{'\\', 'r'}...)
case c < 0x10:
dst = append(dst, []byte{'\\', 'u', '0', '0', '0', 0x57 + c}...)
case c < 0x1a:
dst = append(dst, []byte{'\\', 'u', '0', '0', '1', 0x20 + c}...)
case c < 0x20:
dst = append(dst, []byte{'\\', 'u', '0', '0', '1', 0x47 + c}...)
}
}
dst = append(dst, '"')
return dst
}
func arePointerValuesEqual[V comparable](a *V, b *V) bool {
if a == nil && b == nil {
return true
}
if a != nil && b != nil {
return *a == *b
}
return false
}
func subIdToSerial(subId string) int64 {
n := strings.Index(subId, ":")
if n < 0 || n > len(subId) {
return -1
}
serialId, _ := strconv.ParseInt(subId[0:n], 10, 64)
return serialId
}
func isLowerHex(thing string) bool {
for _, charNumber := range thing {
if (charNumber >= 48 && charNumber <= 57) || (charNumber >= 97 && charNumber <= 102) {
continue
}
return false
}
return true
}