mirror of
https://github.com/vbatts/go-mtree.git
synced 2024-10-31 22:36:38 +00:00
Vincent Batts
08b1000418
The current Vis() and Unvis() are using the C implementation from MTREE(8). But that means that cgo is used, which is not always desired. Signed-off-by: Vincent Batts <vbatts@hashbangbash.com>
89 lines
2.6 KiB
Go
89 lines
2.6 KiB
Go
package mtree
|
|
|
|
import "unicode"
|
|
|
|
// Vis is a wrapper of the C implementation of the function vis, which encodes
|
|
// a character with a particular format/style.
|
|
// For most use-cases use DefaultVisFlags.
|
|
func Vis(src string, flags VisFlag) (string, error) {
|
|
return vis(src, flags)
|
|
}
|
|
|
|
// DefaultVisFlags are the typical flags used for encoding strings in mtree
|
|
// manifests.
|
|
var DefaultVisFlags = VisWhite | VisOctal | VisGlob
|
|
|
|
// VisFlag sets the extent of charactures to be encoded
|
|
type VisFlag int
|
|
|
|
// flags for encoding
|
|
const (
|
|
// to select alternate encoding format
|
|
VisOctal VisFlag = 0x01 // use octal \ddd format
|
|
VisCstyle VisFlag = 0x02 // use \[nrft0..] where appropriate
|
|
|
|
// to alter set of characters encoded (default is to encode all non-graphic
|
|
// except space, tab, and newline).
|
|
VisSp VisFlag = 0x04 // also encode space
|
|
VisTab VisFlag = 0x08 // also encode tab
|
|
VisNl VisFlag = 0x10 // also encode newline
|
|
VisWhite VisFlag = (VisSp | VisTab | VisNl)
|
|
VisSafe VisFlag = 0x20 // only encode "unsafe" characters
|
|
|
|
// other
|
|
VisNoSlash VisFlag = 0x40 // inhibit printing '\'
|
|
VisHttpstyle VisFlag = 0x80 // http-style escape % HEX HEX
|
|
VisGlob VisFlag = 0x100 // encode glob(3) magics
|
|
|
|
)
|
|
|
|
// errors used in the tokenized decoding strings
|
|
const (
|
|
// unvis return codes
|
|
unvisValid unvisErr = 1 // character valid
|
|
unvisValidPush unvisErr = 2 // character valid, push back passed char
|
|
unvisNochar unvisErr = 3 // valid sequence, no character produced
|
|
unvisErrSynbad unvisErr = -1 // unrecognized escape sequence
|
|
unvisErrUnrecoverable unvisErr = -2 // decoder in unknown state (unrecoverable)
|
|
unvisNone unvisErr = 0
|
|
|
|
// unvisEnd means there are no more characters
|
|
unvisEnd VisFlag = 1 // no more characters
|
|
)
|
|
|
|
// unvisErr are the return conditions for Unvis
|
|
type unvisErr int
|
|
|
|
func (ue unvisErr) Error() string {
|
|
switch ue {
|
|
case unvisValid:
|
|
return "character valid"
|
|
case unvisValidPush:
|
|
return "character valid, push back passed char"
|
|
case unvisNochar:
|
|
return "valid sequence, no character produced"
|
|
case unvisErrSynbad:
|
|
return "unrecognized escape sequence"
|
|
case unvisErrUnrecoverable:
|
|
return "decoder in unknown state (unrecoverable)"
|
|
}
|
|
return "Unknown Error"
|
|
}
|
|
|
|
func ishex(r rune) bool {
|
|
lr := unicode.ToLower(r)
|
|
return (lr >= '0' && lr <= '9') || (lr >= 'a' && lr <= 'f')
|
|
}
|
|
|
|
func isoctal(r rune) bool {
|
|
return r <= '7' && r >= '0'
|
|
}
|
|
|
|
// the ctype isgraph is "any printable character except space"
|
|
func isgraph(r rune) bool {
|
|
return unicode.IsPrint(r) && !unicode.IsSpace(r)
|
|
}
|
|
|
|
func isalnum(r rune) bool {
|
|
return unicode.IsNumber(r) || unicode.IsLetter(r)
|
|
}
|