Mercurial > cgi-bin > hgweb.cgi > PassMan
annotate src/main/kotlin/name/blackcap/passman/Shplitter.kt @ 21:ea65ab890f66
More work to support interactive feature.
| author | David Barts <n5jrn@me.com> |
|---|---|
| date | Tue, 02 Jul 2024 11:27:39 -0700 |
| parents | 4391afcf6bd0 |
| children |
| rev | line source |
|---|---|
| 19 | 1 package name.blackcap.passman |
| 2 | |
| 3 // A state is represented by a state-executing function (see below). | |
| 4 typealias State = (Char) -> Boolean | |
| 5 | |
| 6 // Support for simplified *nix shell style splitting into tokens. We are | |
| 7 // focused on splitting things into tokens only. No variable expansion, | |
| 8 // no ~home expansion, etc. Backslash quotes the next character. Single | |
| 9 // quotes quote everything literally up to the next closing single quote. | |
| 10 // Double quotes quote to the closing double quote but honor backslashes | |
| 11 // (i.e. "\"\nice\"" -> "nice"). No \t, \n, \r etc. backslash escapes | |
| 12 // supported (KISS). | |
| 13 class Shplitter() { | |
| 14 private val QUOTING = setOf<State>(::inSingle, ::inDouble) | |
| 15 private val WHITESPACE = setOf<Char>(' ', '\t', '\n') | |
| 16 private var oldStates = mutableListOf<State>() | |
| 17 private var state: State = ::space | |
| 18 private var accum = mutableListOf<String>() | |
| 19 private var current = StringBuilder() | |
| 20 | |
| 21 val complete: Boolean | |
| 22 get() = state == ::space || state == ::nonspace | |
| 23 | |
| 24 // Feeds more input into this tokenizer | |
| 25 fun feed(input: String) : Unit { | |
| 26 for (ch in input) { | |
| 27 while (state(ch)) | |
| 28 ; | |
| 29 } | |
| 30 } | |
| 31 | |
| 32 fun split(): Iterable<String> { | |
| 33 if (complete) { | |
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4391afcf6bd0
Fix more bugs, correct more bad tests.
David Barts <n5jrn@me.com>
parents:
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diff
changeset
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34 if (state == ::nonspace) { |
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4391afcf6bd0
Fix more bugs, correct more bad tests.
David Barts <n5jrn@me.com>
parents:
19
diff
changeset
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35 popState() |
| 19 | 36 accum.add(current.toString()) |
| 37 current.clear() | |
| 38 } | |
| 39 return accum | |
| 40 } else { | |
| 41 throw IllegalStateException("incomplete quoted expression") | |
| 42 } | |
| 43 } | |
| 44 | |
| 45 // State transitions | |
| 46 | |
| 47 private fun pushState(newState: State): Unit { | |
| 48 oldStates.add(state) | |
| 49 state = newState | |
| 50 } | |
| 51 | |
| 52 private fun popState(): Unit { | |
| 53 state = oldStates.removeLast() | |
| 54 } | |
| 55 | |
| 56 private fun lastState(): State = oldStates.last() | |
| 57 | |
| 58 // States. A state is represented by a function that accepts the | |
| 59 // character currently being processed, and returns whether it should | |
| 60 // immediately transition to the next state without reading a new | |
| 61 // character. | |
| 62 | |
| 63 private fun space(ch: Char): Boolean = | |
| 64 when (ch) { | |
| 65 in WHITESPACE -> { false } | |
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20
4391afcf6bd0
Fix more bugs, correct more bad tests.
David Barts <n5jrn@me.com>
parents:
19
diff
changeset
|
66 '\'' -> { pushState(::nonspace); pushState(::inSingle); false } |
|
4391afcf6bd0
Fix more bugs, correct more bad tests.
David Barts <n5jrn@me.com>
parents:
19
diff
changeset
|
67 '"' -> { pushState(::nonspace); pushState(::inDouble); false } |
|
4391afcf6bd0
Fix more bugs, correct more bad tests.
David Barts <n5jrn@me.com>
parents:
19
diff
changeset
|
68 '\\' -> { pushState(::nonspace); pushState(::backslash); false } |
| 19 | 69 else -> { pushState(::nonspace); true } |
| 70 } | |
| 71 | |
| 72 private fun nonspace(ch: Char): Boolean = | |
| 73 when (ch) { | |
| 74 in WHITESPACE -> { | |
| 75 accum.add(current.toString()) | |
| 76 current.clear() | |
| 77 popState() | |
| 78 false | |
| 79 } | |
| 80 '\'' -> { | |
| 81 pushState(::inSingle) | |
| 82 false | |
| 83 } | |
| 84 '"' -> { | |
| 85 pushState(::inDouble) | |
| 86 false | |
| 87 } | |
| 88 '\\' -> { | |
| 89 pushState(::backslash) | |
| 90 false | |
| 91 } | |
| 92 else -> { | |
| 93 current.append(ch) | |
| 94 false | |
| 95 } | |
| 96 } | |
| 97 | |
| 98 private fun inSingle(ch: Char): Boolean = | |
| 99 when (ch) { | |
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20
4391afcf6bd0
Fix more bugs, correct more bad tests.
David Barts <n5jrn@me.com>
parents:
19
diff
changeset
|
100 '\'' -> { popState(); false } |
| 19 | 101 else -> { current.append(ch); false } |
| 102 } | |
| 103 | |
| 104 private fun inDouble(ch: Char): Boolean = | |
| 105 when (ch) { | |
| 106 '\\' -> { pushState(::backslash); false } | |
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20
4391afcf6bd0
Fix more bugs, correct more bad tests.
David Barts <n5jrn@me.com>
parents:
19
diff
changeset
|
107 '"' -> { popState(); false } |
| 19 | 108 else -> { current.append(ch); false } |
| 109 } | |
| 110 | |
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21
ea65ab890f66
More work to support interactive feature.
David Barts <n5jrn@me.com>
parents:
20
diff
changeset
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111 // XXX - multiline commands achieved with backslash-newline |
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ea65ab890f66
More work to support interactive feature.
David Barts <n5jrn@me.com>
parents:
20
diff
changeset
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112 // sequences not supported, so this only works with single- |
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ea65ab890f66
More work to support interactive feature.
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parents:
20
diff
changeset
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113 // line commands. |
| 19 | 114 private fun backslash(ch: Char): Boolean { |
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ea65ab890f66
More work to support interactive feature.
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parents:
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115 // continue existing string no matter what |
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ea65ab890f66
More work to support interactive feature.
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parents:
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116 current.append(ch) |
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ea65ab890f66
More work to support interactive feature.
David Barts <n5jrn@me.com>
parents:
20
diff
changeset
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117 popState() |
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ea65ab890f66
More work to support interactive feature.
David Barts <n5jrn@me.com>
parents:
20
diff
changeset
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118 return false |
| 19 | 119 } |
| 120 } |