1 files changed, 346 insertions, 0 deletions
diff --git a/compiler/parsecfg.nim b/compiler/parsecfg.nim
new file mode 100755
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+++ b/compiler/parsecfg.nim
@@ -0,0 +1,346 @@
+#
+#
+#            Nimrod's Runtime Library
+#        (c) Copyright 2009 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+# A HIGH-PERFORMANCE configuration file parser;
+# the Nimrod version of this file is part of the
+# standard library.
+
+import 
+  llstream, nhashes, strutils, lexbase
+
+type 
+  TCfgEventKind* = enum 
+    cfgEof,                   # end of file reached
+    cfgSectionStart,          # a ``[section]`` has been parsed
+    cfgKeyValuePair,          # a ``key=value`` pair has been detected
+    cfgOption,                # a ``--key=value`` command line option
+    cfgError # an error ocurred during parsing; msg contains the
+             # error message
+  TCfgEvent* = object of TObject
+    case kind*: TCfgEventKind
+    of cfgEof: 
+        nil
+
+    of cfgSectionStart: 
+        section*: string
+
+    of cfgKeyValuePair, cfgOption: 
+        key*, value*: string
+
+    of cfgError: 
+        msg*: string
+
+  
+  TTokKind* = enum 
+    tkInvalid, tkEof,         # order is important here!
+    tkSymbol, tkEquals, tkColon, tkBracketLe, tkBracketRi, tkDashDash
+  TToken*{.final.} = object   # a token
+    kind*: TTokKind           # the type of the token
+    literal*: string          # the parsed (string) literal
+  
+  TParserState* = enum 
+    startState, commaState
+  TCfgParser* = object of TBaseLexer
+    tok*: TToken
+    state*: TParserState
+    filename*: string
+
+
+proc Open*(c: var TCfgParser, filename: string, inputStream: PLLStream)
+proc Close*(c: var TCfgParser)
+proc next*(c: var TCfgParser): TCfgEvent
+proc getColumn*(c: TCfgParser): int
+proc getLine*(c: TCfgParser): int
+proc getFilename*(c: TCfgParser): string
+proc errorStr*(c: TCfgParser, msg: string): string
+# implementation
+
+const 
+  SymChars: TCharSet = {'a'..'z', 'A'..'Z', '0'..'9', '_', '\x80'..'\xFF'} # 
+                                                                           # ----------------------------------------------------------------------------
+
+proc rawGetTok(c: var TCfgParser, tok: var TToken)
+proc open(c: var TCfgParser, filename: string, inputStream: PLLStream) = 
+  openBaseLexer(c, inputStream)
+  c.filename = filename
+  c.state = startState
+  c.tok.kind = tkInvalid
+  c.tok.literal = ""
+  rawGetTok(c, c.tok)
+
+proc close(c: var TCfgParser) = 
+  closeBaseLexer(c)
+
+proc getColumn(c: TCfgParser): int = 
+  result = getColNumber(c, c.bufPos)
+
+proc getLine(c: TCfgParser): int = 
+  result = c.linenumber
+
+proc getFilename(c: TCfgParser): string = 
+  result = c.filename
+
+proc handleHexChar(c: var TCfgParser, xi: var int) = 
+  case c.buf[c.bufpos]
+  of '0'..'9': 
+    xi = (xi shl 4) or (ord(c.buf[c.bufpos]) - ord('0'))
+    inc(c.bufpos)
+  of 'a'..'f': 
+    xi = (xi shl 4) or (ord(c.buf[c.bufpos]) - ord('a') + 10)
+    inc(c.bufpos)
+  of 'A'..'F': 
+    xi = (xi shl 4) or (ord(c.buf[c.bufpos]) - ord('A') + 10)
+    inc(c.bufpos)
+  else: 
+    nil
+
+proc handleDecChars(c: var TCfgParser, xi: var int) = 
+  while c.buf[c.bufpos] in {'0'..'9'}: 
+    xi = (xi * 10) + (ord(c.buf[c.bufpos]) - ord('0'))
+    inc(c.bufpos)
+
+proc getEscapedChar(c: var TCfgParser, tok: var TToken) = 
+  var xi: int
+  inc(c.bufpos)               # skip '\'
+  case c.buf[c.bufpos]
+  of 'n', 'N': 
+    tok.literal = tok.literal & "\n"
+    Inc(c.bufpos)
+  of 'r', 'R', 'c', 'C': 
+    add(tok.literal, CR)
+    Inc(c.bufpos)
+  of 'l', 'L': 
+    add(tok.literal, LF)
+    Inc(c.bufpos)
+  of 'f', 'F': 
+    add(tok.literal, FF)
+    inc(c.bufpos)
+  of 'e', 'E': 
+    add(tok.literal, ESC)
+    Inc(c.bufpos)
+  of 'a', 'A': 
+    add(tok.literal, BEL)
+    Inc(c.bufpos)
+  of 'b', 'B': 
+    add(tok.literal, BACKSPACE)
+    Inc(c.bufpos)
+  of 'v', 'V': 
+    add(tok.literal, VT)
+    Inc(c.bufpos)
+  of 't', 'T': 
+    add(tok.literal, Tabulator)
+    Inc(c.bufpos)
+  of '\'', '\"': 
+    add(tok.literal, c.buf[c.bufpos])
+    Inc(c.bufpos)
+  of '\\': 
+    add(tok.literal, '\\')
+    Inc(c.bufpos)
+  of 'x', 'X': 
+    inc(c.bufpos)
+    xi = 0
+    handleHexChar(c, xi)
+    handleHexChar(c, xi)
+    add(tok.literal, Chr(xi))
+  of '0'..'9': 
+    xi = 0
+    handleDecChars(c, xi)
+    if (xi <= 255): add(tok.literal, Chr(xi))
+    else: tok.kind = tkInvalid
+  else: tok.kind = tkInvalid
+  
+proc HandleCRLF(c: var TCfgParser, pos: int): int = 
+  case c.buf[pos]
+  of CR: result = lexbase.HandleCR(c, pos)
+  of LF: result = lexbase.HandleLF(c, pos)
+  else: result = pos
+  
+proc getString(c: var TCfgParser, tok: var TToken, rawMode: bool) = 
+  var 
+    pos: int
+    ch: Char
+    buf: cstring
+  pos = c.bufPos + 1          # skip "
+  buf = c.buf                 # put `buf` in a register
+  tok.kind = tkSymbol
+  if (buf[pos] == '\"') and (buf[pos + 1] == '\"'): 
+    # long string literal:
+    inc(pos, 2)               # skip ""
+                              # skip leading newline:
+    pos = HandleCRLF(c, pos)
+    buf = c.buf
+    while true: 
+      case buf[pos]
+      of '\"': 
+        if (buf[pos + 1] == '\"') and (buf[pos + 2] == '\"'): break 
+        add(tok.literal, '\"')
+        Inc(pos)
+      of CR, LF: 
+        pos = HandleCRLF(c, pos)
+        buf = c.buf
+        tok.literal = tok.literal & "\n"
+      of lexbase.EndOfFile: 
+        tok.kind = tkInvalid
+        break 
+      else: 
+        add(tok.literal, buf[pos])
+        Inc(pos)
+    c.bufpos = pos +
+        3                     # skip the three """
+  else: 
+    # ordinary string literal
+    while true: 
+      ch = buf[pos]
+      if ch == '\"': 
+        inc(pos)              # skip '"'
+        break 
+      if ch in {CR, LF, lexbase.EndOfFile}: 
+        tok.kind = tkInvalid
+        break 
+      if (ch == '\\') and not rawMode: 
+        c.bufPos = pos
+        getEscapedChar(c, tok)
+        pos = c.bufPos
+      else: 
+        add(tok.literal, ch)
+        Inc(pos)
+    c.bufpos = pos
+
+proc getSymbol(c: var TCfgParser, tok: var TToken) = 
+  var 
+    pos: int
+    buf: cstring
+  pos = c.bufpos
+  buf = c.buf
+  while true: 
+    add(tok.literal, buf[pos])
+    Inc(pos)
+    if not (buf[pos] in SymChars): break 
+  c.bufpos = pos
+  tok.kind = tkSymbol
+
+proc skip(c: var TCfgParser) = 
+  var 
+    buf: cstring
+    pos: int
+  pos = c.bufpos
+  buf = c.buf
+  while true: 
+    case buf[pos]
+    of ' ': 
+      Inc(pos)
+    of Tabulator: 
+      inc(pos)
+    of '#', ';': 
+      while not (buf[pos] in {CR, LF, lexbase.EndOfFile}): inc(pos)
+    of CR, LF: 
+      pos = HandleCRLF(c, pos)
+      buf = c.buf
+    else: 
+      break                   # EndOfFile also leaves the loop
+  c.bufpos = pos
+
+proc rawGetTok(c: var TCfgParser, tok: var TToken) = 
+  tok.kind = tkInvalid
+  setlen(tok.literal, 0)
+  skip(c)
+  case c.buf[c.bufpos]
+  of '=': 
+    tok.kind = tkEquals
+    inc(c.bufpos)
+    tok.literal = "="
+  of '-': 
+    inc(c.bufPos)
+    if c.buf[c.bufPos] == '-': inc(c.bufPos)
+    tok.kind = tkDashDash
+    tok.literal = "--"
+  of ':': 
+    tok.kind = tkColon
+    inc(c.bufpos)
+    tok.literal = ":"
+  of 'r', 'R': 
+    if c.buf[c.bufPos + 1] == '\"': 
+      Inc(c.bufPos)
+      getString(c, tok, true)
+    else: 
+      getSymbol(c, tok)
+  of '[': 
+    tok.kind = tkBracketLe
+    inc(c.bufpos)
+    tok.literal = "["
+  of ']': 
+    tok.kind = tkBracketRi
+    Inc(c.bufpos)
+    tok.literal = "]"
+  of '\"': 
+    getString(c, tok, false)
+  of lexbase.EndOfFile: 
+    tok.kind = tkEof
+  else: getSymbol(c, tok)
+  
+proc errorStr(c: TCfgParser, msg: string): string = 
+  result = `%`("$1($2, $3) Error: $4", 
+               [c.filename, $(getLine(c)), $(getColumn(c)), msg])
+
+proc getKeyValPair(c: var TCfgParser, kind: TCfgEventKind): TCfgEvent = 
+  if c.tok.kind == tkSymbol: 
+    result.kind = kind
+    result.key = c.tok.literal
+    result.value = ""
+    rawGetTok(c, c.tok)
+    while c.tok.literal == ".": 
+      add(result.key, '.')
+      rawGetTok(c, c.tok)
+      if c.tok.kind == tkSymbol: 
+        add(result.key, c.tok.literal)
+        rawGetTok(c, c.tok)
+      else: 
+        result.kind = cfgError
+        result.msg = errorStr(c, "symbol expected, but found: " & c.tok.literal)
+        break 
+    if c.tok.kind in {tkEquals, tkColon}: 
+      rawGetTok(c, c.tok)
+      if c.tok.kind == tkSymbol: 
+        result.value = c.tok.literal
+      else: 
+        result.kind = cfgError
+        result.msg = errorStr(c, "symbol expected, but found: " & c.tok.literal)
+      rawGetTok(c, c.tok)
+  else: 
+    result.kind = cfgError
+    result.msg = errorStr(c, "symbol expected, but found: " & c.tok.literal)
+    rawGetTok(c, c.tok)
+
+proc next(c: var TCfgParser): TCfgEvent = 
+  case c.tok.kind
+  of tkEof: 
+    result.kind = cfgEof
+  of tkDashDash: 
+    rawGetTok(c, c.tok)
+    result = getKeyValPair(c, cfgOption)
+  of tkSymbol: 
+    result = getKeyValPair(c, cfgKeyValuePair)
+  of tkBracketLe: 
+    rawGetTok(c, c.tok)
+    if c.tok.kind == tkSymbol: 
+      result.kind = cfgSectionStart
+      result.section = c.tok.literal
+    else: 
+      result.kind = cfgError
+      result.msg = errorStr(c, "symbol expected, but found: " & c.tok.literal)
+    rawGetTok(c, c.tok)
+    if c.tok.kind == tkBracketRi: 
+      rawGetTok(c, c.tok)
+    else: 
+      result.kind = cfgError
+      result.msg = errorStr(c, "\']\' expected, but found: " & c.tok.literal)
+  of tkInvalid, tkBracketRi, tkEquals, tkColon: 
+    result.kind = cfgError
+    result.msg = errorStr(c, "invalid token: " & c.tok.literal)
+    rawGetTok(c, c.tok)