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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <ctotok.h>
include <error.h>
include <ctype.h>
task sym = t_sym
define LOOKUP 1
define ENTER 2
define MARK 3
define FREE 4
define LISTALL 5
define SQUEEZE 6
define SAVE 7
define RESTORE 8
define INFO 9
define SCANFILE 10
define HELP 11
# SYM -- Test symbol entry and retrieval using the SYMTAB package.
procedure t_sym()
bool timeit
pointer stp, sym
long svtime[2]
char lbuf[SZ_LINE], key[SZ_FNAME]
int ip, lp, stmt, marker, fd, indexlen, stablen, sbuflen, junk
bool clgetb()
int ctowrd(), strlen(), getline(), strmatch()
int stpstr(), sthead(), stnext(), open(), clgeti()
pointer stopen(), stfind(), stenter(), strestore()
begin
indexlen = clgeti ("indexlen")
stablen = clgeti ("stablen")
sbuflen = clgeti ("sbuflen")
timeit = clgetb ("timeit")
stp = stopen ("symtab.zzdebug test symbol table",
indexlen, stablen, sbuflen)
repeat {
call printf ("* ")
call flush (STDOUT)
if (getline (STDIN, lbuf) == EOF) {
call printf ("\n")
break
} else if (strmatch (lbuf, "^bye") > 0)
break
for (ip=1; IS_WHITE(lbuf[ip]); ip=ip+1)
;
# Determine type of statement.
switch (lbuf[ip]) {
case '\n':
next
case '=':
ip = ip + 1
stmt = LOOKUP
default:
if (strmatch (lbuf[ip], "^.mark") > 0) {
stmt = MARK
} else if (strmatch (lbuf[ip], "^.free") > 0) {
stmt = FREE
} else if (strmatch (lbuf[ip], "^.list") > 0) {
stmt = LISTALL
} else if (strmatch (lbuf[ip], "^.squeeze") > 0) {
stmt = SQUEEZE
} else if (strmatch (lbuf[ip], "^.save") > 0) {
stmt = SAVE
ip = ip + 5
} else if (strmatch (lbuf[ip], "^.restore") > 0) {
stmt = RESTORE
ip = ip + 8
} else if (strmatch (lbuf[ip], "^.info") > 0) {
stmt = INFO
ip = ip + 5
} else if (strmatch (lbuf[ip], "^.scanfile") > 0) {
stmt = SCANFILE
ip = ip + 9
} else if (strmatch (lbuf[ip], "^.help") > 0) {
stmt = HELP
ip = ip + 5
} else
stmt = ENTER
}
# Extract key name (or filename).
junk = ctowrd (lbuf, ip, key, SZ_FNAME)
if (timeit)
call sys_mtime (svtime)
switch (stmt) {
case LOOKUP:
# Lookup symbol in table.
sym = stfind (stp, key)
if (sym == NULL) {
call eprintf ("`%s' not found\n")
call pargstr (key)
next
}
# Print keyword = value.
call psym (stp, sym)
case ENTER:
# Enter symbol in table.
sym = stenter (stp, key, 1)
# Get offset of value string.
ip = strmatch (lbuf, "=")
if (ip == 0)
ip = strlen(lbuf) + 1
else {
while (IS_WHITE (lbuf[ip]))
ip = ip + 1
}
# Step on the newline.
for (lp=ip; lbuf[lp] != EOS; lp=lp+1)
if (lbuf[lp] == '\n') {
lbuf[lp] = EOS
break
}
# Deposit value string in symbol table string buffer and save
# offset in symstruct.
Memi[sym] = -stpstr (stp, lbuf[ip], 0)
case MARK:
call stmark (stp, marker)
case FREE:
call stfree (stp, marker)
case LISTALL:
for (sym=sthead(stp); sym != NULL; sym=stnext(stp,sym))
call psym (stp, sym)
case SQUEEZE:
call stsqueeze (stp)
case SAVE:
# In this case 'key' contains the savefile filename.
iferr (call delete (key))
;
iferr (fd = open (key, NEW_FILE, BINARY_FILE)) {
call erract (EA_WARN)
next
}
call stsave (stp, fd)
call close (fd)
case RESTORE:
# In this case 'key' contains the savefile filename.
iferr (fd = open (key, READ_ONLY, BINARY_FILE)) {
call erract (EA_WARN)
next
}
call stclose (stp)
stp = strestore (fd)
call close (fd)
case INFO:
if (key[1] == 'v')
call stinfo (stp, STDOUT, YES)
else
call stinfo (stp, STDOUT, NO)
case SCANFILE:
call scanfile (key, stp)
case HELP:
call zz_help (STDOUT)
default:
call eprintf ("syntax error\n")
}
if (timeit)
call sys_ptime (STDOUT, key, svtime)
}
call stclose (stp)
end
# SCANFILE -- Scan a text file, breaking the input up into a series of tokens.
# Place each new integer token in the symbol table. If the token is already
# present in the table, increment its count field.
procedure scanfile (fname, stp)
char fname[ARB] # file to be scanned
pointer stp # symtab descriptor
char lbuf[SZ_LINE], tokbuf[SZ_FNAME]
int fd, ip, token
pointer sym
int open(), getline(), ctotok()
pointer stenter(), stfind()
errchk open, stenter
begin
fd = open (fname, READ_ONLY, TEXT_FILE)
while (getline (fd, lbuf) != EOF) {
ip = 1
repeat {
token = ctotok (lbuf, ip, tokbuf, SZ_FNAME)
if (token == TOK_IDENTIFIER) {
sym = stfind (stp, tokbuf)
if (sym == NULL) {
sym = stenter (stp, tokbuf, 1)
Memi[sym] = 1
} else
Memi[sym] = Memi[sym] + 1
}
} until (token == TOK_NEWLINE || token == TOK_EOS)
}
call close (fd)
end
# PSYM -- Print the name and value of a symbol in the form "key = value".
# There are two types of values, string and count. A string operand is
# flagged as negative.
procedure psym (stp, sym)
pointer stp # symtab descriptor
pointer sym # pointer to symbol
int val
pointer vp
pointer strefsbuf(), stname()
begin
val = Memi[sym]
if (val < 0) {
vp = strefsbuf (stp, -val)
call printf ("%s = %s\n")
call pargstr (Memc[stname(stp,sym)])
call pargstr (Memc[vp])
} else {
call printf ("%s = %d\n")
call pargstr (Memc[stname(stp,sym)])
call pargi (val)
}
end
# ZZ_HELP -- Print command dictionary for interpreter.
procedure zz_help (fd)
int fd
begin
call fprintf (fd, ".mark mark top of symbol table\n")
call fprintf (fd, ".free free back to last mark\n")
call fprintf (fd, ".list list all symbols in table\n")
call fprintf (fd, ".squeeze minimize storage\n")
call fprintf (fd, ".save <fname> save table in a file\n")
call fprintf (fd, ".restore <fname> restore table from a file\n")
call fprintf (fd, ".info print info on table\n")
call fprintf (fd, ".scanfile <fname> enter symbols from file\n")
call fprintf (fd, "keyword = value enter a symbol in table\n")
call fprintf (fd, "= keyword print value of named symbol\n")
call fprintf (fd, "bye exit\n")
call flush (fd)
end
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