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Diffstat (limited to 'nimlib/pure/lexbase.nim')
| -rwxr-xr-x | nimlib/pure/lexbase.nim | 166 |
1 files changed, 0 insertions, 166 deletions
diff --git a/nimlib/pure/lexbase.nim b/nimlib/pure/lexbase.nim deleted file mode 100755 index bb207e92a..000000000 --- a/nimlib/pure/lexbase.nim +++ /dev/null @@ -1,166 +0,0 @@ -# -# -# The Nimrod Compiler -# (c) Copyright 2009 Andreas Rumpf -# -# See the file "copying.txt", included in this -# distribution, for details about the copyright. -# - -## This module implements a base object of a lexer with efficient buffer -## handling. Only at line endings checks are necessary if the buffer -## needs refilling. - -import - strutils, streams - -const - EndOfFile* = '\0' ## end of file marker - NewLines* = {'\c', '\L'} - -# Buffer handling: -# buf: -# "Example Text\n ha!" bufLen = 17 -# ^pos = 0 ^ sentinel = 12 -# - -type - TBaseLexer* = object of TObject ## the base lexer. Inherit your lexer from - ## this object. - bufpos*: int ## the current position within the buffer - buf*: cstring ## the buffer itself - bufLen*: int ## length of buffer in characters - input: PStream ## the input stream - LineNumber*: int ## the current line number - sentinel: int - lineStart: int # index of last line start in buffer - fileOpened: bool - -proc open*(L: var TBaseLexer, input: PStream, bufLen: int = 8192) - ## inits the TBaseLexer with a stream to read from - -proc close*(L: var TBaseLexer) - ## closes the base lexer. This closes `L`'s associated stream too. - -proc getCurrentLine*(L: TBaseLexer, marker: bool = true): string - ## retrieves the current line. - -proc getColNumber*(L: TBaseLexer, pos: int): int - ## retrieves the current column. - -proc HandleCR*(L: var TBaseLexer, pos: int): int - ## Call this if you scanned over '\c' in the buffer; it returns the the - ## position to continue the scanning from. `pos` must be the position - ## of the '\c'. -proc HandleLF*(L: var TBaseLexer, pos: int): int - ## Call this if you scanned over '\L' in the buffer; it returns the the - ## position to continue the scanning from. `pos` must be the position - ## of the '\L'. - -# implementation - -const - chrSize = sizeof(char) - -proc close(L: var TBaseLexer) = - dealloc(L.buf) - L.input.close(L.input) - -proc FillBuffer(L: var TBaseLexer) = - var - charsRead, toCopy, s: int # all are in characters, - # not bytes (in case this - # is not the same) - oldBufLen: int - # we know here that pos == L.sentinel, but not if this proc - # is called the first time by initBaseLexer() - assert(L.sentinel < L.bufLen) - toCopy = L.BufLen - L.sentinel - 1 - assert(toCopy >= 0) - if toCopy > 0: - MoveMem(L.buf, addr(L.buf[L.sentinel + 1]), toCopy * chrSize) # "moveMem" handles overlapping regions - charsRead = L.input.readData(L.input, addr(L.buf[toCopy]), - (L.sentinel + 1) * chrSize) div chrSize - s = toCopy + charsRead - if charsRead < L.sentinel + 1: - L.buf[s] = EndOfFile # set end marker - L.sentinel = s - else: - # compute sentinel: - dec(s) # BUGFIX (valgrind) - while true: - assert(s < L.bufLen) - while (s >= 0) and not (L.buf[s] in NewLines): Dec(s) - if s >= 0: - # we found an appropriate character for a sentinel: - L.sentinel = s - break - else: - # rather than to give up here because the line is too long, - # double the buffer's size and try again: - oldBufLen = L.BufLen - L.bufLen = L.BufLen * 2 - L.buf = cast[cstring](realloc(L.buf, L.bufLen * chrSize)) - assert(L.bufLen - oldBuflen == oldBufLen) - charsRead = L.input.ReadData(L.input, addr(L.buf[oldBufLen]), - oldBufLen * chrSize) div chrSize - if charsRead < oldBufLen: - L.buf[oldBufLen + charsRead] = EndOfFile - L.sentinel = oldBufLen + charsRead - break - s = L.bufLen - 1 - -proc fillBaseLexer(L: var TBaseLexer, pos: int): int = - assert(pos <= L.sentinel) - if pos < L.sentinel: - result = pos + 1 # nothing to do - else: - fillBuffer(L) - L.bufpos = 0 # XXX: is this really correct? - result = 0 - L.lineStart = result - -proc HandleCR(L: var TBaseLexer, pos: int): int = - assert(L.buf[pos] == '\c') - inc(L.linenumber) - result = fillBaseLexer(L, pos) - if L.buf[result] == '\L': - result = fillBaseLexer(L, result) - -proc HandleLF(L: var TBaseLexer, pos: int): int = - assert(L.buf[pos] == '\L') - inc(L.linenumber) - result = fillBaseLexer(L, pos) #L.lastNL := result-1; // BUGFIX: was: result; - -proc skip_UTF_8_BOM(L: var TBaseLexer) = - if (L.buf[0] == '\xEF') and (L.buf[1] == '\xBB') and (L.buf[2] == '\xBF'): - inc(L.bufpos, 3) - inc(L.lineStart, 3) - -proc open(L: var TBaseLexer, input: PStream, bufLen: int = 8192) = - assert(bufLen > 0) - assert(input != nil) - L.input = input - L.bufpos = 0 - L.bufLen = bufLen - L.buf = cast[cstring](alloc(bufLen * chrSize)) - L.sentinel = bufLen - 1 - L.lineStart = 0 - L.linenumber = 1 # lines start at 1 - fillBuffer(L) - skip_UTF_8_BOM(L) - -proc getColNumber(L: TBaseLexer, pos: int): int = - result = abs(pos - L.lineStart) - -proc getCurrentLine(L: TBaseLexer, marker: bool = true): string = - var i: int - result = "" - i = L.lineStart - while not (L.buf[i] in {'\c', '\L', EndOfFile}): - add(result, L.buf[i]) - inc(i) - add(result, "\n") - if marker: - add(result, RepeatChar(getColNumber(L, L.bufpos)) & "^\n") - |