mirror of
https://github.com/minio/minio.git
synced 2024-12-26 23:25:54 -05:00
74 lines
2.3 KiB
Go
74 lines
2.3 KiB
Go
//+build !appengine
|
|
|
|
package gjson
|
|
|
|
import (
|
|
"reflect"
|
|
"unsafe"
|
|
)
|
|
|
|
// getBytes casts the input json bytes to a string and safely returns the
|
|
// results as uniquely allocated data. This operation is intended to minimize
|
|
// copies and allocations for the large json string->[]byte.
|
|
func getBytes(json []byte, path string) Result {
|
|
var result Result
|
|
if json != nil {
|
|
// unsafe cast to string
|
|
result = Get(*(*string)(unsafe.Pointer(&json)), path)
|
|
result = fromBytesGet(result)
|
|
}
|
|
return result
|
|
}
|
|
|
|
func fromBytesGet(result Result) Result {
|
|
// safely get the string headers
|
|
rawhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Raw))
|
|
strhi := *(*reflect.StringHeader)(unsafe.Pointer(&result.Str))
|
|
// create byte slice headers
|
|
rawh := reflect.SliceHeader{Data: rawhi.Data, Len: rawhi.Len}
|
|
strh := reflect.SliceHeader{Data: strhi.Data, Len: strhi.Len}
|
|
if strh.Data == 0 {
|
|
// str is nil
|
|
if rawh.Data == 0 {
|
|
// raw is nil
|
|
result.Raw = ""
|
|
} else {
|
|
// raw has data, safely copy the slice header to a string
|
|
result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
|
|
}
|
|
result.Str = ""
|
|
} else if rawh.Data == 0 {
|
|
// raw is nil
|
|
result.Raw = ""
|
|
// str has data, safely copy the slice header to a string
|
|
result.Str = string(*(*[]byte)(unsafe.Pointer(&strh)))
|
|
} else if strh.Data >= rawh.Data &&
|
|
int(strh.Data)+strh.Len <= int(rawh.Data)+rawh.Len {
|
|
// Str is a substring of Raw.
|
|
start := int(strh.Data - rawh.Data)
|
|
// safely copy the raw slice header
|
|
result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
|
|
// substring the raw
|
|
result.Str = result.Raw[start : start+strh.Len]
|
|
} else {
|
|
// safely copy both the raw and str slice headers to strings
|
|
result.Raw = string(*(*[]byte)(unsafe.Pointer(&rawh)))
|
|
result.Str = string(*(*[]byte)(unsafe.Pointer(&strh)))
|
|
}
|
|
return result
|
|
}
|
|
|
|
// fillIndex finds the position of Raw data and assigns it to the Index field
|
|
// of the resulting value. If the position cannot be found then Index zero is
|
|
// used instead.
|
|
func fillIndex(json string, c *parseContext) {
|
|
if len(c.value.Raw) > 0 && !c.calcd {
|
|
jhdr := *(*reflect.StringHeader)(unsafe.Pointer(&json))
|
|
rhdr := *(*reflect.StringHeader)(unsafe.Pointer(&(c.value.Raw)))
|
|
c.value.Index = int(rhdr.Data - jhdr.Data)
|
|
if c.value.Index < 0 || c.value.Index >= len(json) {
|
|
c.value.Index = 0
|
|
}
|
|
}
|
|
}
|