Tech Arsenal 1/Tech Arsenal (Arsenal Computer).ISO/tek-01/cxref200.zip/CXREF.DOC

Text File | 1993-01-04 | 6KB | 136 lines

           CXREF - C Program Cross Reference Generator
                  Version: 2.00     June 24, 1986


    CXREF produces a cross-reference listing for a C program  and
optional  graphical  representation of the block structure of the
program.  Occurrences only are listed.  No  distinction  is  made
between  definitions  and  references.  Version 2.00 of CXREF has
been converted from Turbo Pascal source  into  C  source.  The  C
compiler  used  was  Datalight's small model compiler however the
source appears to be reasonably standard and little effort should
be required to convert it to any other C.


USAGE:

    The command line for CXREF has the following format:

        CXREF input_file_name [output_file_name] [options]

    Both the input_file_name and the output_file_name may be full
PC/MS-DOS path names.  The output_file_name is  optional.  If  is
is  not  supplied,  the output file will be created with the same
name as the input file but  with  an  extension  of  LST.  If  no
extension  is  specified  for the input file,  an extension of .C
will be assumed.  If an output file name is specified but without
an extension, an extension of LST will be assumed.

    The current version of CXREF supports three flag options and
two options that require an additional parameter.

    Flag Options:

        -NL  - Suppress  the  graphical  representation  of   the
               program  and  the  line  numbered  listing  of the
               program.

        -NS  - Suppress cross-referencing of C keywords.

        -NI  - Suppress analysis of #include files.

    Value Options:

        -I <path>  - Supplies the path for  #include  <file_name>
                     files.  Must b followed by the pathname.

        -T <n>     - Sets  the  tab stop value for tab expansion.
                     The default value is 4.

    The  default  condition  is  to  produce  the  line  numbered
listing,   including  all  #include  files,   showing  the  block
structure and to cross-reference all symbols.

    If executed with  no  command  line  parameters,  CXREF  will
display a brief summary of its usage.


INCLUDE FILES:

    This version of CXREF will process single level include files
of  either  the  quote  delimited  or the angle bracket ['<','>']
forms.  Quote delimited include files are  located  in  the  same
directory  as  the  input  program  and  angle  bracket delimited
include   files   are   located   in   a   "system"    directory.
Unfortunately,  there  is  no  standard  "system" directory under
PC/MS-DOS and the various C compilers use a number  of  different
mechanisms  to  provide  a  "system"  directory.  To  handle  the
different "system" directories, CXREF provides the "-I" option on
the command line,  allowing the user to provide a  path  for  all
angle bracket delimited include files.

    CXREF can handle up to 26 include files, distinguished by the
letters  A  through  Z  following  the  line  numbers in both the
listing and the cross-reference.  The line numbers shown, both on
the listing and in the cross-reference,  are  true  line  numbers
within  the  file  making the cross-reference without the listing
useful.



HISTORY OF DEVELOPMENT:

    This program has  had  a  long  history.  It  was  originally
written  for  Pascal  programs  by N.  Wirth using the "quadratic
quotient" hash method.  It was adapted for UCSD Pascal (1.4 - the
public  domain  version)  by  Shawn   Fanning   (in   1978)   and
subsequently  adapted  for  Pascal/MT+  by Mike Lehman (in 1981).
This version was then modified by Warren A.  Smith to try to  get
back  to ISO standard Pascal and to add the additional feature of
mapping out the compound statements.  It was modified  for  Turbo
Pascal  by  Ron  Finger in July,  1984.  This last version of the
program, at least, was named XLIST.

    Further modifications were made by Larry Dodson in September,
1985.   These  include  the  ability  to  handle  Include  files,
expansion   of   the   identifier  field  from  eight  to  twelve
characters,  optional  suppression  of  the  output  of  standard
identifiers,  a margin on the left of the output to provide space
to punch holes for a three-ring binder, and a compile time option
of 66 or 88 lines per page.  In addition,  several comments  were
added,  blocking  (for  readability)  was improved,  the name was
changed from XLIST  to  XREF,  and  several  other  less  evident
corrections  and  modifications were incorporated.  These changes
were made and tested using Turbo Pascal (Version 2.0 for CP/M 80)
on a Kaypro II with an Okidata 82 printer.

    NXREF was then produced by  Don  Williams  as  practically  a
complete  rewrite  of  XREF.  Binary  trees  were  used  for  the
references rather than the 'quadratic quotient' used by XREF (the
binary tree routines used,  however,  are simple  adaptations  of
those  presented  by  N.  Wirth  in  his  excellent  book,  "Data
Structures + Algorithms = Programs".) The program was modified to
take advantage of the Turbo Pascal  3.0  Command  Line  parameter
features.  The  case  structure  of  the  first  occurrence of an
identifier  was  preserved  (XREF   and   XLIST   converted   all
identifiers to upper case in the cross-reference.

    Use  of  the  binary  tree  routines  and  dynamic allocation
allowed the maximum length of an identifier to be increased to 29
bytes.  In NXREF,  this length  is  determined  by  the  printout
format rather than the structure that holds the references.

    Upon realizing that a similar facility would be useful for C
programs, I modified NXREF into CXREF.  Since, from the viewpoint
of structure and cross-reference, the differences between Pascal
and C are slight, it was a relatively simple modification.

    CXREF200 and beyond have been converted to  C  with  CXREF200
being  in Datalight C.  Future releases of this program may be in
some other C source.