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include "../lib/parser.h"
include "../lib/prdefs.h"
# PR_PARSE - Parser driver routine for the parser generated by xyacc. This
# procedure opens the configuration file, and call the parser generated by
# xyacc. It returns ERR if errors are found in the configuration file, and
# OK for no errors. All tables allocated by this procedure MUST be freed
# by the calling program if there are no errors. Otherwise they are freed
# before exiting the procedure.
int procedure pr_parse (fname)
char fname[ARB] # solution file name
int fd # input file descriptor
include "lexer.com"
extern pr_lexer()
int open(), parse(), pr_geti()
#pointer pr_getp()
begin
# Open the input file.
if (fname[1] == EOS)
call error (0, "ERROR: The configuration file is undefined")
else
fd = open (fname, READ_ONLY, TEXT_FILE)
# Initialize the lexer common variables.
nlines = 0
pos = 1
call strcpy ("\n", line, SZ_LINE)
call strcpy ("", id, SZ_LINE)
# Allocate space for parser symbol tables, and code generation table.
call pr_alloc ()
call pr_calloc ()
# Initialize the counters.
call pr_puti (NERRORS, 0)
call pr_puti (NWARNINGS, 0)
call pr_puti (NOBSVARS, 0)
call pr_puti (NCATVARS, 0)
call pr_puti (NFITPARS, 0)
call pr_puti (NTOTPARS, 0)
call pr_puti (NSETEQS, 0)
call pr_puti (NEXTEQS, 0)
call pr_puti (NTRNEQS, 0)
# Initialize the flags.
call pr_puti (FLAGERRORS, YES)
# Initialize the minimum and maximum column values.
call pr_puti (MINCOL, 1)
call pr_puti (MINOBSCOL, INDEFI)
call pr_puti (MINCATCOL, INDEFI)
call pr_puti (MAXOBSCOL, INDEFI)
call pr_puti (MAXCATCOL, INDEFI)
# Parse the input stream. Syntax errors are flaged by an ERR parse()
# value. Semantic errors are not detected by the parser, but instead
# by the symbol table procedures. The latter, do not raise an error
# condition, but they send error messages to the standard output if
# the FLAGERR flag is set to YES.
if (parse (fd, false, pr_lexer) == ERR)
call pr_error ("Cannot continue parsing", PERR_SYNTAX)
# Debug ?
#call dg_prvdump ("From pr_parse before pr_exit")
#call dg_prtdump ("From pr_parse before pr_exit", pr_getp (SYMTABLE))
# Check consistency of the symbol table only if there
# are no errors during the parse. This check may give
# some errors undetected during the previous parse.
if (pr_geti (NERRORS) == 0)
call pr_exit ()
# Free code buffer and and close the input file.
call pr_cfree ()
call close (fd)
# Debug ?
#call dg_prvdump ("From pr_parse")
#call dg_prtdump ("From pr_parse", pr_getp (SYMTABLE))
# Return value. If there are errors free all the tables
# allocated before. Otherwise, keep all tables for later
# use. They MUST be freed by the calling program.
# Return the appropriate error code.
if (pr_geti (NERRORS) == 0) {
call pr_puti (FLAGERRORS, NO)
return (OK)
} else {
call pr_free ()
return (ERR)
}
end
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