[boost] [BGL] Bug and proposed patch for read_graphviz to read dos formatted .dot files

From: Tan Kwee Heong (tan.k.h_at_[hidden])
Date: 2005-07-04 00:31:15

Hi,

I am submitting this bug and proposed patch as outlined in the procedure
in http://www.boost.org/more/bugs.htm. Let me know if more information is
needed. Also, since my patch is just a proposed solution, I am open to a
better solution, etc because there may be issues I am not aware of and
therefore,
not taken into account.

Bug description :
   Platform - Win2K
   Compiler - Cygwin g++ 3.3.1

   read_graphviz when compiled with g++ will only read .dot in unix format,
and
   fails with a "Syntax error" for .dot files in dos format. For comparison,
read_graphviz
   when compiled with VC7.1 will read .dot files created in both formats.

   FYI : A text file created in dos format has line terminations as
   \r\n while a text file created in unix forma has line terminations in \n.

Proposed fix:
   This patch allows the graphviz_lex.ll to consider both \n and \r\n as
line terminations,
   thereby allowing read_graphviz to work on .dot files created in dos and
unix format,
   regardless of which platform/compiler BGL was compiled on.

   This is also consistent with the Windows Graphviz tools like dotty, that
also work
   regardless of whether the .dot files are of unix or dos format.

   Essentially, an additional rule is added to graphviz_lex.ll to recognize
and discard
   \r\n.

Attached file : graphviz_lex.ll.patch

begin 666 graphviz_lex.ll.patch
M*BHJ(&=R87!H=FEZ7VQE>"YM86EN+FQL"5-U;B!*=6P@(#,@,C$Z,# Z,C,@
M,C P-0HM+2T_at_9W)A<&AV:7I?;&5X+FQL"5-U;B!*=6P@(#,@,C$Z,#8Z,3 @
M,C P-0HJ*BHJ*BHJ*BHJ*BHJ*BH**BHJ(#@X+#DS("HJ*BH*+2TM(#@X+#DT
M("TM+2T*(" \3&ET97)A;#Y;7%Q=6UQN72 @(" @.PH@(#Q,:71E<F%L/BA;
M7B)<7%TJ?%M<7%TN*2 @>R!A9&1?<W1R:6YG*'EY=&5X="D[('T*("!;(%QT
M72 @(" @(" @(" @.PHK(%QR7&X@(" @(" @(" @(" ["B @7&X@(" @(" @
M(" @(" @(#L*(" N(" @(" @(" @(" @(" @>R!R971U<FX@>7ET97AT6S!=
).R!]"B @)24*
`
end