%%s 4/4/591
%%d D 1.2 20-Sep-82 17:05:26 dpm 2 1
%%c Modified fb.w`fb.r`printb so that the "-c" switch will work.  The
%%c test for (endstk == 0 & fb == ERR) was moved after the test for
%%c (count == YES).
%%s 0/0/0
%%d D 1.1 25-Mar-82 12:05:44 v1.1 1 0
%%c Version 1.1 is the Spring 1982 Distribution of the LBL/Hughes release
%%c of the Software Tools Virtual Operating System software and documentation.
%%T
%%I 1
#-h- fbbuf            321  asc  25-mar-82 07:53:39  v1.1 (sw-tools v1.1)
 ## fbbuf - common block for 'fb'  block buffer
 common /fbbuf/ fbbuf(MAXBUFLENGTH), endstk,
                fname(FILENAMESIZE), fb
 
 character fbbuf	#buffer which holds lines
 integer endstk		#pointer to end of stack; init=0
 character fname	#holds name of scratch file
 integer fb		#file ID of scratch file; init=ERR
#-h- fbcom           1309  asc  25-mar-82 07:53:41  v1.1 (sw-tools v1.1)
 ## /fbcom/ - common block for 'bf' tool
 #  Put on a file called 'fbcom'
 # Used only by 'fb', but very similar to variables used in 'find'
 
 common /fbcom/ andpat, count, except, elevel, casind,
              pat(MAXPAT, NEXPR),
              atend, atbeg, seps(MAXPAT,2),
	      nbrsep, skping, prting,
	      mcount, seploc, bklth, lcount,
              locatd(NEXPR)
 
 integer andpat		#flag for locating blocks which contain all args
 integer count		#flag for counting occurrences only
 integer except		#flag for locating blocks without indicated patterns
 integer elevel		#number of patterns to locate
 integer casind		#YES/NO if match is case-independent
 integer pat		#patterns to locate
 integer atend		#flag for indicating end of block reached
 integer atbeg		#flag indicating beginning of block reached
 integer seps		#block separator(s) (1=start,2=ending)
 integer nbrsep		#number of separators (1 or 2)
 integer seploc         #location of separator (BEFORE or AFTER block)
 integer mcount		#count of number of matches
 integer skping		#flag indicating lines should not be examined
 character locatd	#flag indicating which patterns have been located
 integer bklth          #max size of block to output
                        # init = HUGE
 integer lcount         #running line count of block
#-h- fbtemp            97  asc  25-mar-82 07:53:43  v1.1 (sw-tools v1.1)
common / fbtemp / tmpbuf(MAXLINE)

character tmpbuf	# temporary buffer used by checkl and bmatch
%%D 2
#-h- fb.r           11293  asc  25-mar-82 07:53:49  v1.1 (sw-tools v1.1)
%%E 2
%%I 2
#-h- fb.r           11290  asc  20-sep-82 17:01:46  dpm (dave martin)
%%E 2
#-h- defns            497  asc  25-mar-82 07:52:37  v1.1 (sw-tools v1.1)
 define(NEXPR,10)		# max number of expressions
ifdef(LARGE_ADDRESS_SPACE)
  define(MAXBUFLENGTH,20000)	# length of block buffer (characters)
elsedef
  define(MAXBUFLENGTH,5000)      #length of block buffer (characters)
enddef
 define(BEFORE,1)               #separator at beginning of block
 define(AFTER,0)                #separator at end of block
 define(HUGE,30000)		# just a large number
 define(mkuniq,scratf)
 define(USE_STRING,"usage:  fb [-acix] [-ln] [-sexpr [-sexpr]] expr [expr] ...")
#-h- main             344  asc  25-mar-82 07:52:39  v1.1 (sw-tools v1.1)
 DRIVER(fb)

 ## fb - find block of lines

 include fbcom
 
 call query(USE_STRING)
 call fbargs            #set initial values; parse args
 
 call dobk (STDIN)              #search blocks for patterns
 if (count == YES)              #print final count
        {
        call putdec(mcount, 1)
        call putc('@n')
        }
 
 DRETURN
 end
#-h- bmatch           378  asc  25-mar-82 07:52:41  v1.1 (sw-tools v1.1)
 ## bmatch - locate patterns which appear in line of block
 subroutine bmatch (line)
 character line(ARB)
 integer match
 
 include fbcom
 include fbtemp
 
 call strcpy(line, tmpbuf)
 if (casind == YES)
    call fold(tmpbuf)
 for (i=1; i<=elevel; i=i+1)
        if (match(tmpbuf, pat(1,i)) == YES)
                locatd(i) = YES         #mark arg that was matched
 return
 end
#-h- checkl           344  asc  25-mar-82 07:52:42  v1.1 (sw-tools v1.1)
 ## checkl - check line for block separator
 subroutine checkl (line)
 character line(ARB)
 integer match
 
 include fbcom
 include fbtemp
 
 call strcpy(line, tmpbuf)
 if (casind == YES)
    call fold(tmpbuf)
 atbeg = match(tmpbuf, seps(1,1))
 if (nbrsep == 1)
        atend = atbeg
 else
        atend = match(tmpbuf, seps(1,2))
 return
 end
#-h- dobeg            390  asc  25-mar-82 07:52:44  v1.1 (sw-tools v1.1)
## dobeg - process beginning of block (fb tool)
 
 subroutine dobeg (line)
 
 character line(ARB)
 integer stackl
 
 include fbcom
 
 call initbk            #clear stacks
 lcount = 0
 if (nbrsep > 1 | seploc == BEFORE)
        {
        call bmatch(line)
        if (stackl(line) == ERR)
                call error ("Block buffer overflow")
        }
 skping = NO
 prting = NO
 return
 end
#-h- dobk            1025  asc  25-mar-82 07:52:46  v1.1 (sw-tools v1.1)
 ## dobk - find patterns in block of text
 subroutine dobk (fd)
 
 integer getlin, remove
 integer fd, prt, first, junk
 character line(MAXLINE)
 
 include fbcom
 include fbbuf
 
 call initbk                    #clear stacks
 first = YES
 while(getlin(line, fd) != EOF)
        {
        call checkl (line)      #check line for block separator
                        #check if sep really at start of block
        if (first == YES & atend == YES & nbrsep == 1)
                seploc = BEFORE
        first = NO
        if (atend == YES)
                call doend(line)
        if (atbeg == YES)
                {
                call dobeg(line)
                next
                }
        if (skping == YES)
                next
        else call dolin (line)
        }
 
                        #EOF reached
 if (skping == NO)
        call doend(line)
 
 if (fb != ERR)         #make sure scratch file is removed
        {
        call close(fb)
        junk = remove(fname)
        fb = ERR
        }
 return
 end
 
#-h- doend           1059  asc  25-mar-82 07:52:49  v1.1 (sw-tools v1.1)
 ## doend - process end of block (fb tool)
 
 subroutine doend (line)
 
 character line(ARB)
 integer stackl
 integer prt
 include fbcom
 
 if (prting == YES)
        {
        if ( (nbrsep > 1 | seploc == AFTER) & count == NO)
                call outlin(line)
        if (bklth != HUGE)      #finish off rest of block
                for(lcount=lcount+1; lcount<=bklth; lcount=lcount+1)
                        call putch('@n', STDOUT)
        }
 else if (skping == NO)
        {
        if (nbrsep > 1 | seploc == AFTER)
                {
                call bmatch (line)
                if (stackl(line) ==ERR)
                        call error ("Block buffer overflow")
                }
        call tally (prt)
        if (prt == YES)
                {
                call printb
                if (bklth != HUGE)
                        for (lcount=lcount+1; lcount<=bklth;
                             lcount=lcount+1)
                                call putch('@n',STDOUT)
                }
        }
 skping = YES
 prting = NO
 
 return
 end
#-h- dolin            794  asc  25-mar-82 07:52:51  v1.1 (sw-tools v1.1)
 ## dolin - process line for 'fb' tool
 
 subroutine dolin (line)
 
 character line(ARB)
 integer prt
 integer stackl
 
 include fbcom
 
 if (skping == YES)
        return
 if (prting == YES)
        {
        if (count == NO)
                call outlin(line)
        }
 else                   #check line for match
        {
        call bmatch (line)
        if (stackl(line) == ERR)
                call error ("Block buffer overflow")
        call tally(prt)
                #block may definitely be printed
        if (prt == YES & except == NO)
                {
                call printb
                prting = YES
                }
                  #block may definitely be skipped
        else if (prt == NO & except == YES)
                skping = YES
        }
 
 return
 end
#-h- fbargs          2409  asc  25-mar-82 07:52:55  v1.1 (sw-tools v1.1)
 
 ## fbargs - parse arguments for 'fb' tool
 
 subroutine fbargs
 character arg(MAXLINE)
 integer getarg, itoc, getpat, status, index, ctoi
 integer i, j
 
 include fbbuf
 include fbcom
 string ilpat "illegal pattern: "
 string maxexp "max nbr expressions allowed: "
 string dsep "% *$"
 data except/NO/
 data andpat/NO/
 data count /NO/
 data mcount /0/
 data elevel/0/
 data casind/NO/
 data skping /NO/
 data nbrsep /0/
 data seploc /AFTER/
 data endstk /0/
 data fb /ERR/
 data bklth /HUGE/
 data lcount /0/

                #loop thru args, picking up flags and patterns
 for (i=1; getarg(i, arg, MAXARG) != EOF; i=i+1)
    {
    if (arg(1) == '-' & (arg(2) == 's' | arg(2) == 'S'))
        {
        nbrsep = nbrsep + 1
        if (nbrsep > 2)
                call error ("only start and ending separators allowed")
        if (casind == YES)
          call fold(arg)
        if (getpat(arg(3), seps(1, nbrsep)) == ERR)
                {
                call putlin(ilpat, ERROUT)
                call error (arg(3))
                }
        }
    else if (arg(1) == '-')
        {
        call fold(arg)
        if (index(arg, 'a') > 0)
            andpat = YES
        if (index(arg, 'c') > 0)
            count = YES
        if (index(arg, 'i') > 0)
            casind = YES
        if (index(arg, 'x') > 0)
            except = YES
        j = index(arg, 'l')
        if (j > 0)               #setting block length
                {
                j = j + 1
                bklth = ctoi(arg, j)
                if (bklth <= 0)
                        call error(USE_STRING)
                }
        }
    else if (elevel < NEXPR)
        {
        elevel = elevel + 1
        if (casind == YES)
            call fold(arg)
        if (getpat(arg(1), pat(1,elevel)) == ERR)
                {
                call putlin(ilpat, ERROUT)
                call error (arg)
                }
        }
    else
        {
        call putlin(maxexp, ERROUT)
        status = itoc(NEXPR, arg, MAXARG)
        call error(arg)
        }
    }
                #check for errors
 if (elevel == 0)
    call error(USE_STRING)
 
 if (nbrsep == 0)       #set default separator
        {
        if (getpat(dsep, seps(1,1)) == ERR)
                call error ("illegal default separator")
        nbrsep = 1
        }
 
 if (nbrsep > 1)        #skip till beginning of first block
        skping = YES
 return
 end
#-h- initbk           312  asc  25-mar-82 07:52:58  v1.1 (sw-tools v1.1)
 ## initbk - initialize buffers for 'fb' tool
 subroutine initbk

 integer junk
 integer remove
 
 include fbcom
 include fbbuf
 
 for (i=1; i<=elevel; i=i+1)
        locatd(i) = NO
 endstk = 0
 if (fb != ERR)
        {
        call close(fb)
        junk = remove(fname)
        fb = ERR
        }
 return
 end
#-h- outlin           214  asc  25-mar-82 07:53:00  v1.1 (sw-tools v1.1)
 ## outlin - output line from block, if user wants to see it
 subroutine outlin(line)
 character line(ARB)
 include fbcom
 
 lcount = lcount + 1
 if (lcount <= bklth)
        call putlin(line, STDOUT)
 return
 end
%%D 2
#-h- printb           778  asc  25-mar-82 07:53:01  v1.1 (sw-tools v1.1)
%%E 2
%%I 2
#-h- printb           778  asc  20-sep-82 16:43:19  dpm (dave martin)
%%E 2
 ## printb - print (or count) block of lines
 subroutine printb
 integer i, junk
 character c
 character getch
 integer open, remove
 
 include fbbuf
 include fbcom
 
%%D 2
 if (endstk == 0 & fb == ERR)           #nothing on stack
        return
%%E 2
 if (count == YES)
        {
        mcount = mcount + 1
        return
        }
%%I 2
 if (endstk == 0 & fb == ERR)           #nothing on stack
        return
%%E 2
 if (fb != ERR)         #copy scratch file to output
        {
        call close(fb)
        fb = open(fname, READ)  #start at beginning
        if (fb == ERR)
                call error ("problems reopening scratch file")
        while(getch(c, fb) != EOF)
                call putch(c, STDOUT)
        call close(fb)
        junk = remove (fname)
        fb = ERR
        }
 for (i=1; i<=endstk; i=i+1)
        call putch(fbbuf(i), STDOUT)
 return
 end
#-h- stackl          1069  asc  25-mar-82 07:53:04  v1.1 (sw-tools v1.1)
 ## stackl - put line on bottom of stack (if user wants to see it)
 
 integer function stackl (line)
 character line(MAXLINE)
 integer length, create
 integer len
 
 include fbbuf
 include fbcom
 
  string fbtemp "fbt"
 
 stackl = OK
 if (count == YES)      #no need to stack if just counting
        return
 lcount = lcount + 1
 if (lcount > bklth)    #user doesn't want to see this much
        return
 len = length(line)
 if ( (len+endstk+1) > MAXBUFLENGTH)    #store buffer on scratch file
        {
        if (fb == ERR)
                {
                call mkuniq(fbtemp, fname)
                fb = create(fname, WRITE)
                if (fb == ERR)
                        {
                        call remark ("problems opening scratch file")
                        call cant (fname)
                        }
                }
        for (i=1; i<=endstk; i=i+1)
                call putch(fbbuf(i), fb)
        call putlin(line, fb)
        endstk = 0
        return
        }
 call scopy(line, 1, fbbuf, endstk+1)
 endstk = endstk + len 
 return
 end
#-h- tally            658  asc  25-mar-82 07:53:06  v1.1 (sw-tools v1.1)
 ## tally - tally results of block search
 subroutine tally (prt)
 integer prt    #returned as YES if block should be printed; else NO
 
 include fbcom
 
 prt = andpat
 for (i=1; i<=elevel; i=i+1)
        {
        if (andpat == NO & locatd(i) == YES)
                {
                prt = YES
                break
                }
        else if (andpat == YES & locatd(i) == NO)
                {
                prt = NO
                break
                }
        }
 
 if (except == YES)             #opposite for exceptions
        {
        if (prt == NO)
                prt = YES
        else
                prt = NO
        }
 return
 end
#-h- fb.fmt          2942  asc  25-mar-82 07:53:58  v1.1 (sw-tools v1.1)
.so ~bin/manhdr
.hd Fb (1) 28-May-80
search blocks of lines for text patterns
.sy
fb [-acix] [-ln] [-sexpr [-sexpr]] expr [expr] ...
.ds
"Fb" (find block) searches blocks or groups of lines in a file for
text patterns.
It is similar to 'find' except that if a pattern is found,
the entire block of lines is copied to standard output,
rather than simply the line in which the pattern occurred.
Thus it is useful for searching mailing lists, bibliographies,
and similar files where several lines are grouped together to
form cohesive units.
 
The search patterns may be any regular expression as described
in the 'ed' and 'find' writeups.
 
"Fb"
assumes the blocks of lines are separated by an empty line or a
line containing only blanks.
When "fb" is called without any options, standard input is read
and each line is checked to see if it matches any of the regular
expressions given as arguments.
If any matches are found,
the entire block is printed on standard output.
 
Other options include:
 
.in +10
.ti -8
-a      Only print the block if ALL the arguments are found within it
 
.ti -8
-x      Only print the block if none of the arguments are 
found within it
 
.ti -8
-c      Only print a COUNT of the number of blocks found which
match/don't match the expressions
 
.ti -8
-i      Perform the pattern matches ignoring case.

.ti -8
-sexpr  Use 'expr' as the block separator (instead of a blank or
empty line).  "Expr" can be a regular expression just as
the search arguments can.
 
If two "-sexpr" arguments are given, the first one is considered
to be the pattern which starts a block (e.g. -ssubroutine) and
the second is considered the pattern which ends a block 
(e.g. -send).
If the -i flag has been seen before the -s flags, then the start and
end expressions will be case-independent.
 
.ti -8
-ln     prints only the first 'n' lines of the block;
if the block contains less than 'n' lines, the block is padded
out with blank lines.
.in -10
  
.fi 
Care should be taken when using the characters % $ [ ] ! * @ and 
any shell characters
in the text pattern. It is often necessary to enclose the 
entire substitution pattern in quotes. 
.fl
A scratch file ("fbt") is used if the internal line buffer
becomes full.
.sa
find
.br
ed

For a complete description of regular expressions, see
"Software Tools" pages 135-154.
.di
Error messages are given if:
.br
.in +3
a)  One of the patterns given is illegal
.br
b)  Too many separators are given (2 are allowed)
.br
c)  The maximum number of expressions is exceeded (9 are allowed)
.br
d)  There are problems opening the scratch file (when the block line
buffer fills up).
 
.in -3
If the following messages show up, something is dreadfully wrong:
.in +3
a)  "Illegal default separator"
.br
b)  "Block buffer overflow"
.in -3
.au
Debbie Scherrer (Lawrence Berkeley Laboratory)
.bu
An expression may not start with a minus sign (-).

Regular expressions cannot span line boundaries.
%%E 1