#!/bin/sh

# defines (originally what-defs)                            30 Nov 2003
# version:
            v="4.1.1"
#
# usage:  defines [-d] [-i] [cc-name [cc-opts]]
#
# Print names and values of predefined cpp macros, plus sizes of basic
# C variable types.  By default check standard "cc", but GNU C or another
# compiler may be checked instead by giving "gcc" (or whatever) as an
# argument (name only, no path).  If the first argument is the compiler
# name, up to four additional arguments may be included as options for
# the compiler to alter the preprocessor behavior.  Note that poking
# through the preprocessor(s) may take a while (e.g., Cray scpp is 8MB)
# and that cc on at least some systems (e.g., SCO) is executable but not
# world-readable.  This version now fails gracefully if all compiler com-
# ponents are unreadable by the user (thanks to James Birdsall for the
# suggestion).
#
# With the -i option, defines will also check strings found in system header
# files, at least some of which are likely to be predefined (Dan Quinlan
# idea).  This can be very slow, however, and might cause overflows on some
# systems.
#
# The -d option turns on debugging output; it shows what binaries are being
# searched, which may indicate the source of the problem if some of the
# standard macros aren't found ("... should already be listed above").
#
# defines uses the following more-or-less standard Unix utilities:
#
#    /bin/sh [echo, test]  date  uname  sed  strings  tr  sort  rm  cat
#
# plus, of course, the C preprocessor and compiler.  "date" and "uname"
# are used only for identifying info and may be omitted (Convex doesn't
# have the latter, for example).
#
# Written by Robert Skinner, Skip Montanaro, Greg Roelofs, John Bush,
# Kjetil Jørgensen and others; original author unknown.  Versions 2.0 through
# 3.18 maintained by GRR (newt at pobox.com).
#
# Versions 4.0 and later are maintained by Bjørn Reese (breese at
# users.sourceforge.net) and distributed via http://predef.sourceforge.net/ .
#
# Changelog:
#   4.0  20030622  Bjorn Reese
#     * Added sizes of pointer-to-object and pointer-to-function.
#
#   4.1  20030629  Bjorn Reese
#     * Using CHAR_BIT to calculate sizes.
#
#   4.1.1  20031130  Greg Roelofs
#     * Added some GCC-specific "long long" macros (note:  uses defined(),
#       not ifdef--break into four-level nested block to support K&R compilers)

# parse options, if any (change "if" to "while" if add more options)

DEBUG=" > /dev/null"
doincl=false
while [ $# -ne 0 ]; do
    case "$1" in
        -d)   DEBUG=""
              shift ;;
        -i)   doincl=true
              shift ;;
        *)    break ;;
    esac
done


# print some helpful identifying info for those who collect these things

echo \
  'This is output from `defines'"' version $v, from your buddies at Newtware!"
date


# search the path for uname and strings (apparently "which" is broken in some
# versions of Ultrix, and "test" does not accept the -x option)

path="`echo $PATH | sed -e 's/:/ /g'`"
unpath=`for dir in $path ; do
    if [ -r $dir/uname ]; then
        echo $dir/uname
        exit
    fi
done`
if [ "$unpath" != "" ]; then
    $unpath -a
else
    echo "[no uname command]"
fi
strpath=`for dir in $path ; do
    if [ -r $dir/strings ]; then
        echo $dir/strings
        exit
    fi
done`

if [ "$1" != "" ]; then
    if [ "`basename $1`" != "$1" ]; then
        cc=`basename $1`
        ccpath=`dirname $1`
        path="$path $ccpath"
    else
        cc=$1
    fi
    echo "cc = [$*]"
    shift
else
    cc=cc
    echo "cc = [$cc]"
fi
echo ""


# this is the start of a *really big* if-block; look for "END IF-BLOCK 1"
# about 135 lines down...

if [ "$strpath" = "" ]; then
    echo "$0:  error: no "'`'"strings' command...giving up."
else


# search the path for the compiler

if [ "$ccpath" = "" ]; then
    ccpath=`for dir in $path ; do
        if [ -r $dir/$cc ]; then
            echo $dir
            exit
        fi
    done`
fi
eval 'echo "debug:  ccpath = [$ccpath]"'"$DEBUG"
if [ "$ccpath" = "" ]; then
    echo "$0:  warning: $cc unreadable (can't search for strings)"
fi


# create a list of possible preprocessors; cd into /tmp now to avoid
# problems with "." in path during "cc -v" compilation
#   $dir/$cc/*cpp    :  Convex cc; *not* caught by "cc -v":  no -v option
#   $dir/SC*/*comp   :  SunOS acc; caught by "cc -v" test below
#   /etc/*.cfg       :  AIX C Set++ config file; caught by "cc -v"?
#   /usr/lpp/xlc/bin :  AIX C Set++; not caught by "cc -v" (apparently)
#   $dir/cpp.ansi    :  HP-UX
#   /usr/lib/cmplrs/<compiler>/{decc,driver,cfe} : DEC Ultrix and OSF/1;
  
cd /tmp
cpp=`for file in /etc/*.cfg ; do
    if [ -r $file ]; then
        echo $file
    fi
done
for dir in $path /lib /usr/lib /usr/local/lib /usr/lib/cmplrs/$cc /usr/lpp/$cc/bin ; do
    for file in $dir/*cpp* $dir/*cc $dir/*comp $dir/$cc/*cpp ; do
        if [ -r $file ]; then
            echo $file
        fi
    done
    # these are Ultrix- and AIX-specific, sigh:
    for file in $dir/driver $dir/cfe $dir/xlc* ; do
        if [ -r $file ]; then
            echo $file
        fi
    done
done`
eval 'echo "debug:  cpp = [$cpp]"'"$DEBUG"
if [ "$cpp" = "" ]; then
    echo "$0:  warning: preprocessor(s) unreadable (can't search for strings)"
fi


# grab all possible compiler components out of "cc -v" output (catches GNU
# cpp and Sun acomp, in particular) and "cc -#" output (catches DNIX cc and
# dcc; others?).  awkward tr syntax is required due to incompatibilities
# between behaviors of different vendors' versions, e.g., Convex and SGI
# (generic BSD/SysV problem?)

echo "int i;" > /tmp/def$$.c
ccv=`2>&1 $ccpath/$cc -v -c /tmp/def$$.c |
  tr ' \009()<>,;:&|' '\012\012\012\012\012\012\012\012\012\012\012' |
  grep '^/' |
  grep -v '/tmp/' |
  grep -v '\.o$' |
  sort -u`
eval 'echo "debug:  ccv = [$ccv]"'"$DEBUG"
ccv2=`2>&1 $ccpath/$cc -# -c /tmp/def$$.c |
  tr ' \009()<>,;:&|' '\012\012\012\012\012\012\012\012\012\012\012' |
  grep '^/' |
  grep -v '/tmp/' |
  grep -v '\.o$' |
  sort -u`
eval 'echo "debug:  ccv2 = [$ccv2]"'"$DEBUG"
cleanccv=`for file in $ccv $ccv2 ; do
    if [ -r $file -a ! -d $file ]; then
        echo $file
    fi
done`
eval 'echo "debug:  cleanccv = [$cleanccv]"'"$DEBUG"
# temp files used again for stropts, below


# if requested, grab header files, too:  even if all compiler components
# unreadable, system header files should reference at least some of the
# predefined macros [drawback:  potentially very slow; may increase number
# of strings tested by more than an order of magnitude]

if [ $doincl = true ]; then
    incl=`for dir in /usr/*include/ /usr/*include/*/ ; do
        for file in $dir/*.h ; do
            if [ -r $file ]; then
                echo $file
            fi
        done
    done | sed 's#//#/#g'`
else
    incl=
fi
eval 'echo "debug:  incl = [$incl]"'"$DEBUG"


# if nothing is readable, no point in continuing:  strings would hang (this
# is the start of another big if-block; look for "END IF-BLOCK 2" about 50
# lines down)

all=`echo $ccpath/$cc $cpp $cleanccv $incl | tr ' ' '\012' | sort -u`
eval 'echo "debug:  all = [$all]"'"$DEBUG"
if [ "$all" = "" ]; then
    echo "$0:  error: all compiler components unreadable...giving up."
else


# figure out proper "strings" options for searching entire executable with
# minimum string-length 2

stropt1="-a"
2>&1 $strpath $stropt1 /tmp/def$$.c > /dev/null
if [ $? -ne 0 ]; then
    stropt1="-"
    2>&1 $strpath $stropt1 /tmp/def$$.c > /dev/null
    if [ $? -ne 0 ]; then
        # Coherent (`uname -v` = "COHERENT") doesn't have *either* option
        stropt1=""
    fi
fi
eval 'echo "debug:  stropt1 = [$stropt1]"'"$DEBUG"

# some versions of GNU strings (e.g., 2.4) have a nasty bug wherein "-2" is
# interpreted as "-50" or something; therefore try "-n 2" version first

stropt2="-n 2"
2>&1 $strpath $stropt2 /tmp/def$$.c > /dev/null
if [ $? -ne 0 ]; then
    stropt2="-2"
    # GRR:  I trust there's no version so pathetic it doesn't have a min-length
fi
eval 'echo "debug:  stropt2 = [$stropt2]"'"$DEBUG"

stropts="$stropt1 $stropt2"
eval 'echo "debug:  stropts = [$stropts]"'"$DEBUG"
rm -f /tmp/def$$.c /tmp/def$$.o


# create a pseudo-C "program" with every possible #ifdef included; quote
# each macro once to avoid expansion, then print it again to get its value.
# (the "char foo" shenanigans are necessary to work around a bug in the
# brain-damaged NeXT preprocessor; and DNIX has a broken sort, so an extra
# "sort | " should be prepended to the "sort -u" line)

# [GRR:  could also write "cc -v" output to tmp file and add that to
# strings list...]

$strpath $stropts $all |
tr -s " =:;,{}" '\012\012\012\012\012\012\012' |
sed -e 's/^-D//' |
sed -n '/^[a-zA-Z_][a-zA-Z0-9_]*$/p' |
sort -u |
sed 's/^.*$/#ifdef &\
char foo[] = "%&"	= &;\
#endif/' > /tmp/def$$.c


# preprocess the "program" to figure out which of the possible macros are real

$ccpath/$cc $1 $2 $3 $4 -E /tmp/def$$.c |
  sed -n '/^char.*"%/s///p' |
  sed -e 's/"//' -e 's/;//'
rm -f /tmp/def$$.c


fi   # END IF-BLOCK 2
fi   # END IF-BLOCK 1
#-----------------------------------------------------------------------------

echo ""


# compile another program to check for oversights and get sizes of basic types
# (the \\" combos around the %s fields and the sed-backslash command are re-
# quired to work around Coherent bug:  plain \" loses backslash)

cat << END_O_DE_LINE | sed 's/\\\\/\\/g' > /tmp/def$$.c
#include <stdio.h>
#include <limits.h>
#ifndef CHAR_BIT
#define CHAR_BIT 8
#endif
main()
{
    printf("Checking other possibilities; should already be listed above:\n");
#ifdef __COHERENT__
    printf("__COHERENT__\t= 0x%04x (when stdio.h #included)\n", __COHERENT__);
#endif
#ifdef __ANSI__
    printf("__ANSI__\t= %d\n", __ANSI__);
#endif
#ifdef __DATE__
    printf("__DATE__\t= \\"%s\\"\n", __DATE__);
#endif
#ifdef __FILE__
    printf("__FILE__\t= \\"%s\\"\n", __FILE__);
#endif
#ifdef __GNUC__
    printf("__GNUC__\t= %d\n", __GNUC__);
#endif
#ifdef __LINE__
    printf("__LINE__\t= %d\n", __LINE__);
#endif
#ifdef __STDC__
    printf("__STDC__\t= %d\n", __STDC__);
#endif
#ifdef __TIME__
    printf("__TIME__\t= \\"%s\\"\n", __TIME__);
#endif
    printf("\nSizes of basic variable types:\n");
    printf("  sizeof(char)           = %d bits\n", CHAR_BIT*sizeof(char));
    printf("  sizeof(short)          = %d bits\n", CHAR_BIT*sizeof(short));
    printf("  sizeof(int)            = %d bits\n", CHAR_BIT*sizeof(int));
    printf("  sizeof(long)           = %d bits\n", CHAR_BIT*sizeof(long));
#if defined(_LONGLONG) || defined(__USE_ISOC99) || defined(__GLIBC_HAVE_LONG_LONG) || defined(LLONG_MAX)
    printf("  sizeof(long long)      = %d bits\n", CHAR_BIT*sizeof(long long));
#endif
    printf("  sizeof(float)          = %d bits\n", CHAR_BIT*sizeof(float));
    printf("  sizeof(double)         = %d bits\n", CHAR_BIT*sizeof(double));
#ifdef __STDC__
    printf("  sizeof(long double)    = %d bits\n", CHAR_BIT*sizeof(long double));
#endif
    printf("  sizeof(char *)         = %d bits\n", CHAR_BIT*sizeof(char *));
    printf("  sizeof(char (*)(char)) = %d bits\n", CHAR_BIT*sizeof(char (*)(char)));
}
END_O_DE_LINE

$ccpath/$cc $1 $2 $3 $4 -o /tmp/def$$ /tmp/def$$.c
/tmp/def$$
rm -f /tmp/def$$.c /tmp/def$$

exit 0