1 files changed, 297 insertions, 0 deletions
diff --git a/lexlua/awk.lua b/lexlua/awk.lua
new file mode 100644
index 000000000..a3f69fd83
--- /dev/null
+++ b/lexlua/awk.lua
@@ -0,0 +1,297 @@
+-- Copyright 2006-2018 Mitchell mitchell.att.foicica.com. See License.txt.
+-- AWK LPeg lexer.
+-- Modified by Wolfgang Seeberg 2012, 2013.
+
+local lexer = require('lexer')
+local token, word_match = lexer.token, lexer.word_match
+local P, R, S = lpeg.P, lpeg.R, lpeg.S
+
+local lex = lexer.new('awk')
+
+local LEFTBRACKET = '['
+local RIGHTBRACKET = ']'
+local SLASH = '/'
+local BACKSLASH = '\\'
+local CARET = '^'
+local CR = '\r'
+local LF = '\n'
+local CRLF = CR .. LF
+local DQUOTE = '"'
+local DELIMITER_MATCHES = {['('] = ')', ['['] = ']'}
+local COMPANION = {['('] = '[', ['['] = '('}
+local CC = {
+  alnum = 1, alpha = 1, blank = 1, cntrl = 1, digit = 1, graph = 1, lower = 1,
+  print = 1, punct = 1, space = 1, upper = 1, xdigit = 1
+}
+local LastRegexEnd = 0
+local BackslashAtCommentEnd = 0
+local KW_BEFORE_RX = {
+  case = 1, ['do'] = 1, ['else'] = 1, exit = 1, print = 1, printf = 1,
+  ['return'] = 1
+}
+
+local function findKeyword(input, e)
+  local i = e
+  while i > 0 and input:find("^[%l]", i) do i = i - 1 end
+  local w = input:sub(i + 1, e)
+  if i == 0 then
+    return KW_BEFORE_RX[w] == 1
+  elseif input:find("^[%u%d_]", i) then
+    return false
+  else
+    return KW_BEFORE_RX[w] == 1
+  end
+end
+
+local function isRegex(input, i)
+  while i >= 1 and input:find('^[ \t]', i) do i = i - 1 end
+  if i < 1 then return true end
+  if input:find("^[-!%%&(*+,:;<=>?[^{|}~\f]", i) or findKeyword(input, i) then
+    return true
+  elseif input:sub(i, i) == SLASH then
+    return i ~= LastRegexEnd -- deals with /xx/ / /yy/.
+  elseif input:find('^[]%w)."]', i) then
+    return false
+  elseif input:sub(i, i) == LF then
+    if i == 1 then return true end
+    i = i - 1
+    if input:sub(i, i) == CR then
+      if i == 1 then return true end
+      i = i - 1
+    end
+  elseif input:sub(i, i) == CR then
+    if i == 1 then return true end
+    i = i - 1
+  else
+    return false
+  end
+  if input:sub(i, i) == BACKSLASH and i ~= BackslashAtCommentEnd then
+    return isRegex(input, i - 1)
+  else
+    return true
+  end
+end
+
+local function eatCharacterClass(input, s, e)
+  local i = s
+  while i <= e do
+    if input:find('^[\r\n]', i) then
+      return false
+    elseif input:sub(i, i + 1) == ':]' then
+      local str = input:sub(s, i - 1)
+      return CC[str] == 1 and i + 1
+    end
+    i = i + 1
+  end
+  return false
+end
+
+local function eatBrackets(input, i, e)
+  if input:sub(i, i) == CARET then i = i + 1 end
+  if input:sub(i, i) == RIGHTBRACKET then i = i + 1 end
+  while i <= e do
+    if input:find('^[\r\n]', i) then
+      return false
+    elseif input:sub(i, i) == RIGHTBRACKET then
+      return i
+    elseif input:sub(i, i + 1) == '[:' then
+      i = eatCharacterClass(input, i + 2, e)
+      if not i then return false end
+    elseif input:sub(i, i) == BACKSLASH then
+      i = i + 1
+      if input:sub(i, i + 1) == CRLF then i = i + 1 end
+    end
+    i = i + 1
+  end
+  return false
+end
+
+local function eatRegex(input, i)
+  local e = #input
+  while i <= e do
+    if input:find('^[\r\n]', i) then
+      return false
+    elseif input:sub(i, i) == SLASH then
+      LastRegexEnd = i
+      return i
+    elseif input:sub(i, i) == LEFTBRACKET then
+      i = eatBrackets(input, i + 1, e)
+      if not i then return false end
+    elseif input:sub(i, i) == BACKSLASH then
+      i = i + 1
+      if input:sub(i, i + 1) == CRLF then i = i + 1 end
+    end
+    i = i + 1
+  end
+  return false
+end
+
+local ScanRegexResult
+local function scanGawkRegex(input, index)
+  if isRegex(input, index - 2) then
+    local i = eatRegex(input, index)
+    if not i then
+      ScanRegexResult = false
+      return false
+    end
+    local rx = input:sub(index - 1, i)
+    for bs in rx:gmatch("[^\\](\\+)[BSsWwy<>`']") do
+      -- /\S/ is special, but /\\S/ is not.
+      if #bs % 2 == 1 then return i + 1 end
+    end
+    ScanRegexResult = i + 1
+  else
+    ScanRegexResult = false
+  end
+  return false
+end
+-- Is only called immediately after scanGawkRegex().
+local function scanRegex()
+  return ScanRegexResult
+end
+
+local function scanString(input, index)
+  local i = index
+  local e = #input
+  while i <= e do
+    if input:find('^[\r\n]', i) then
+      return false
+    elseif input:sub(i, i) == DQUOTE then
+      return i + 1
+    elseif input:sub(i, i) == BACKSLASH then
+      i = i + 1
+      -- lexer.delimited_range() doesn't handle CRLF.
+      if input:sub(i, i + 1) == CRLF then i = i + 1 end
+    end
+    i = i + 1
+  end
+  return false
+end
+
+-- purpose: prevent isRegex() from entering a comment line that ends with a
+-- backslash.
+local function scanComment(input, index)
+  local _, i = input:find('[^\r\n]*', index)
+  if input:sub(i, i) == BACKSLASH then BackslashAtCommentEnd = i end
+  return i + 1
+end
+
+local function scanFieldDelimiters(input, index)
+  local i = index
+  local e = #input
+  local left = input:sub(i - 1, i - 1)
+  local count = 1
+  local right = DELIMITER_MATCHES[left]
+  local left2 = COMPANION[left]
+  local count2 = 0
+  local right2 = DELIMITER_MATCHES[left2]
+  while i <= e do
+    if input:find('^[#\r\n]', i) then
+      return false
+    elseif input:sub(i, i) == right then
+      count = count - 1
+      if count == 0 then return count2 == 0 and i + 1 end
+    elseif input:sub(i, i) == left then
+      count = count + 1
+    elseif input:sub(i, i) == right2 then
+      count2 = count2 - 1
+      if count2 < 0 then return false end
+    elseif input:sub(i, i) == left2 then
+      count2 = count2 + 1
+    elseif input:sub(i, i) == DQUOTE then
+      i = scanString(input, i + 1)
+      if not i then return false end
+      i = i - 1
+    elseif input:sub(i, i) == SLASH then
+      if isRegex(input, i - 1) then
+        i = eatRegex(input, i + 1)
+        if not i then return false end
+      end
+    elseif input:sub(i, i) == BACKSLASH then
+      if input:sub(i + 1, i + 2) == CRLF then
+        i = i + 2
+      elseif input:find('^[\r\n]', i + 1) then
+        i = i + 1
+      end
+    end
+    i = i + 1
+  end
+  return false
+end
+
+-- Whitespace.
+lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))
+
+-- Comments.
+lex:add_rule('comment', token(lexer.COMMENT, '#' * P(scanComment)))
+
+-- Strings.
+lex:add_rule('string', token(lexer.STRING, DQUOTE * P(scanString)))
+
+-- No leading sign because it might be binary.
+local float = ((lexer.digit^1 * ('.' * lexer.digit^0)^-1) +
+               ('.' * lexer.digit^1)) *
+              (S('eE') * S('+-')^-1 * lexer.digit^1)^-1
+
+-- Fields. E.g. $1, $a, $(x), $a(x), $a[x], $"1", $$a, etc.
+lex:add_rule('field',
+             token('field', P('$') * S('$+-')^0 *
+                            (float +
+                             lexer.word^0 * '(' * P(scanFieldDelimiters) +
+                             lexer.word^1 * ('[' * P(scanFieldDelimiters))^-1 +
+                             '"' * P(scanString) +
+                             '/' * P(eatRegex) * '/')))
+lex:add_style('field', lexer.STYLE_LABEL)
+
+-- Regular expressions.
+-- Slash delimited regular expressions are preceded by most operators or
+-- the keywords 'print' and 'case', possibly on a preceding line. They
+-- can contain unescaped slashes and brackets in brackets. Some escape
+-- sequences like '\S', '\s' have special meanings with Gawk. Tokens that
+-- contain them are displayed differently.
+lex:add_rule('gawkRegex', token('gawkRegex', SLASH * P(scanGawkRegex)))
+lex:add_style('gawkRegex', lexer.STYLE_PREPROCESSOR..',underlined')
+lex:add_rule('regex', token(lexer.REGEX, SLASH * P(scanRegex)))
+
+-- Operators.
+lex:add_rule('gawkOperator', token('gawkOperator', P("|&") + "@" + "**=" +
+                                                   "**"))
+lex:add_style('gawkOperator', lexer.STYLE_OPERATOR..',underlined')
+lex:add_rule('operator', token(lexer.OPERATOR, S('!%&()*+,-/:;<=>?[\\]^{|}~')))
+
+-- Numbers.
+lex:add_rule('gawkNumber', token('gawkNumber', lexer.hex_num + lexer.oct_num))
+lex:add_style('gawkNumber', lexer.STYLE_NUMBER..',underlined')
+lex:add_rule('number', token(lexer.NUMBER, float))
+
+-- Keywords.
+lex:add_rule('keyword', token(lexer.KEYWORD, word_match[[
+  BEGIN END atan2 break close continue cos delete do else exit exp fflush for
+  function getline gsub if in index int length log match next nextfile print
+  printf rand return sin split sprintf sqrt srand sub substr system tolower
+  toupper while
+]]))
+
+lex:add_rule('builtInVariable', token('builtInVariable', word_match[[
+  ARGC ARGV CONVFMT ENVIRON FILENAME FNR FS NF NR OFMT OFS ORS RLENGTH RS RSTART
+  SUBSEP
+]]))
+lex:add_style('builtInVariable', lexer.STYLE_CONSTANT)
+
+lex:add_rule('gawkBuiltInVariable', token('gawkBuiltInVariable', word_match[[
+  ARGIND BINMODE ERRNO FIELDWIDTHS FPAT FUNCTAB IGNORECASE LINT PREC PROCINFO
+  ROUNDMODE RT SYMTAB TEXTDOMAIN
+]]))
+lex:add_style('gawkBuiltInVariable', lexer.STYLE_CONSTANT..',underlined')
+
+-- Functions.
+lex:add_rule('function', token(lexer.FUNCTION, lexer.word * #P('(')))
+
+-- Identifiers.
+lex:add_rule('identifier', token(lexer.IDENTIFIER, lexer.word))
+
+-- Fold points.
+lex:add_fold_point(lexer.OPERATOR, '{', '}')
+lex:add_fold_point(lexer.COMMENT, '#', lexer.fold_line_comments('#'))
+
+return lex