#!/usr/bin/mawk -f

# find include dependencies in C source
#
# mawk -f deps.awk C_source_files
# -- prints a dependency list suitable for make
# -- ignores #include < >
#


BEGIN { stack_index = 0 # stack[] holds the input files

for(i = 1 ; i < ARGC ; i++)
{
file = ARGV[i]
if ( file !~ /\.[cC]$/ ) continue # skip it
outfile = substr(file, 1, length(file)-2) ".o"

# INCLUDED[] stores the set of included files
# -- start with the empty set
for( j in INCLUDED ) delete INCLUDED[j]

while ( 1 )
{
if ( getline line < file <= 0 ) # no open or EOF
{ close(file)
if ( stack_index == 0 ) break # empty stack
else
{ file = stack[ stack_index-- ]
continue
}
}

if ( line ~ /^#include[ \t]+".*"/ )
{
split(line, X, "\"") # filename is in X[2]

if ( X[2] in INCLUDED ) # we've already included it
continue

#push current file
stack[ ++stack_index ] = file
INCLUDED[ file = X[2] ] = ""
}
} # end of while

# test if INCLUDED is empty
flag = 0 # on once the front is printed
for( j in INCLUDED )
if ( ! flag )
{ printf "%s : %s" , outfile, j ; flag = 1 }
else printf " %s" , j

if ( flag ) print ""

}# end of loop over files in ARGV[i]

}