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The 640 MEG Shareware Studio 2
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The 640 Meg Shareware Studio CD-ROM Volume II (Data Express)(1993).ISO
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os2
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pccts.zip
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DLG_P.G
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1992-12-08
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9KB
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343 lines
/* This is the parser for the dlg version 2
* This is a part of the Purdue Compiler Construction Toolset
* 8/18/90
*
* Will Cohen
*
*/
#header <<
#include <ctype.h>
#include "dlg.h"
#ifdef MEMCHK
#include "trax.h"
#else
extern char *malloc();
extern char *calloc();
#endif
>>
<<
int action_no = 0; /* keep track of actions outputed */
int nfa_allocated = 0; /* keeps track of number of nfa nodes */
nfa_node *nfa_array = NULL;/* root of binary tree that stores nfa array */
nfa_node nfa_model_node; /* model to initialize new nodes */
set used_chars; /* used to label trans. arcs */
set used_classes; /* classes or chars used to label trans. arcs */
set normal_chars; /* mask to get rid elements that aren't used
in set */
int flag_paren = FALSE;
int flag_brace = FALSE;
int mode_counter = 0; /* keep track of number of %%names */
>>
#lexaction <<
#include "dlgdef.h"
int func_action; /* should actions be turned into functions?*/
int lex_mode_counter = 0; /* keeps track of the number of %%names */
>>
#token "[\r\t\ ]+" << zzskip(); >> /* Ignore white */
#token "[\n]" << zzline++; zzskip(); >> /* Track Line # */
#token L_EOF "\@"
#token PER_PER "\%\%"
#token NAME_PER_PER "\%\%[a-zA-Z_][a-zA-Z0-9_]*"
<< p_mode_def(&zzlextext[2],lex_mode_counter++); >>
#token ACTION "\<\<"
<< if (func_action)
fprintf(OUT,"static void\nact%d()\n{ ", ++action_no);
zzmode(ACT); zzskip();
>>
#token GREAT_GREAT "\>\>"
#token L_BRACE "\{"
#token R_BRACE "\}"
#token L_PAR "\("
#token R_PAR "\)"
#token L_BRACK "\["
#token R_BRACK "\]"
#token ZERO_MORE "\*"
#token ONE_MORE "\+"
#token OR "\|"
#token RANGE "\-"
#token NOT "\~"
#token OCTAL_VALUE "\\0[0-7]*"
<< {int t; sscanf(&zzlextext[1],"%o",&t); zzlextext[0] = t;}>>
#token HEX_VALUE "\\0[Xx][0-9a-fA-F]+"
<< {int t; sscanf(&zzlextext[1],"%x",&t); zzlextext[0] = t;}>>
#token DEC_VALUE "\\[1-9][0-9]*"
<< {int t; sscanf(&zzlextext[1],"%d",&t); zzlextext[0] = t;}>>
#token TAB "\\t" << zzlextext[0] = '\t';>>
#token NL "\\n" << zzlextext[0] = '\n';>>
#token CR "\\r" << zzlextext[0] = '\r';>>
#token BS "\\b" << zzlextext[0] = '\b';>>
/* NOTE: this takes ANYTHING after the \ */
#token LIT "\\~[tnrb]" << zzlextext[0] = zzlextext[1];>>
/* NOTE: this takes ANYTHING that doesn't match the other tokens */
#token REGCHAR "~[\\]"
grammar : << p_head(); func_action = FALSE;>> (ACTION)* start_states
<< func_action = FALSE; p_tables(); p_tail(); >>
(ACTION)* "@"
;
start_states : ( PER_PER do_conversion
| NAME_PER_PER do_conversion (NAME_PER_PER do_conversion)*)
PER_PER
;
do_conversion : <<new_automaton_mode(); func_action = TRUE;>>
rule_list
<<
dfa_class_nop[mode_counter] =
relabel($1.l,comp_level);
if (comp_level)
p_shift_table(mode_counter);
dfa_basep[mode_counter] = dfa_allocated+1;
make_dfa_model_node(dfa_class_nop[mode_counter]);
nfa_to_dfa($1.l);
++mode_counter;
func_action = FALSE;
>>
;
rule_list : rule <<$$.l=$1.l; $$.r=$1.r;>>
(rule
<<{nfa_node *t1;
t1 = new_nfa_node();
(t1)->trans[0]=$$.l;
(t1)->trans[1]=$1.l;
/* all accept nodes "dead ends" */
$$.l=t1; $$.r=NULL;
}
>>
)*
| /* empty */
<<$$.l = new_nfa_node(); $$.r = NULL;
warning("no regular expressions", zzline);
>>
;
rule : reg_expr ACTION
<<$$.l=$1.l; $$.r=$1.r; ($1.r)->accept=action_no;>>
| ACTION
<<$$.l = NULL; $$.r = NULL;
error("no expression for action ", zzline);
>>
;
reg_expr : and_expr <<$$.l=$1.l; $$.r=$1.r;>>
(OR and_expr
<<{nfa_node *t1, *t2;
t1 = new_nfa_node(); t2 = new_nfa_node();
(t1)->trans[0]=$$.l;
(t1)->trans[1]=$2.l;
($$.r)->trans[1]=t2;
($2.r)->trans[1]=t2;
$$.l=t1; $$.r=t2;
}
>>
)*
;
and_expr : repeat_expr <<$$.l=$1.l; $$.r=$1.r;>>
(repeat_expr <<($$.r)->trans[1]=$1.l; $$.r=$1.r;>>)*
;
repeat_expr : expr <<$$.l=$1.l; $$.r=$1.r;>>
{ ZERO_MORE
<<{ nfa_node *t1,*t2;
($$.r)->trans[0] = $$.l;
t1 = new_nfa_node(); t2 = new_nfa_node();
t1->trans[0]=$$.l;
t1->trans[1]=t2;
($$.r)->trans[1]=t2;
$$.l=t1;$$.r=t2;
}
>>
| ONE_MORE
<<($$.r)->trans[0] = $$.l;>>
}
| ZERO_MORE
<< error("no expression for *", zzline);>>
| ONE_MORE
<< error("no expression for +", zzline);>>
;
expr : L_BRACK atom_list R_BRACK
<< $$.l = new_nfa_node(); $$.r = new_nfa_node();
($$.l)->trans[0] = $$.r;
($$.l)->label = set_dup($2.label);
set_orin(&used_chars,($$.l)->label);
>>
| NOT L_BRACK atom_list R_BRACK
<< $$.l = new_nfa_node(); $$.r = new_nfa_node();
($$.l)->trans[0] = $$.r;
($$.l)->label = set_dif(normal_chars,$3.label);
set_orin(&used_chars,($$.l)->label);
>>
| L_PAR reg_expr R_PAR
<< $$.l = new_nfa_node(); $$.r = new_nfa_node();
($$.l)->trans[0] = $2.l;
($2.r)->trans[1] = $$.r;
>>
| L_BRACE reg_expr R_BRACE
<< $$.l = new_nfa_node(); $$.r = new_nfa_node();
($$.l)->trans[0] = $2.l;
($$.l)->trans[1] = $$.r;
($2.r)->trans[1] = $$.r;
>>
| atom
<< $$.l = new_nfa_node(); $$.r = new_nfa_node();
($$.l)->trans[0] = $$.r;
($$.l)->label = set_dup($1.label);
set_orin(&used_chars,($$.l)->label);
>>
;
atom_list : << set_free($$.label); >>
(near_atom <<set_orin(&($$.label),$1.label);>>)*
;
near_atom : << register int i;
register int i_prime;
>>
anychar
<<$$.letter=$1.letter; $$.label=set_of($1.letter);
i_prime = $1.letter + MIN_CHAR;
if (case_insensitive && islower(i_prime))
set_orel(toupper(i_prime)-MIN_CHAR,
&($$.label));
if (case_insensitive && isupper(i_prime))
set_orel(tolower(i_prime)-MIN_CHAR,
&($$.label));
>>
{ RANGE anychar
<< for (i=$$.letter; i<= $2.letter; ++i){
set_orel(i,&($$.label));
i_prime = i+MIN_CHAR;
if (case_insensitive && islower(i_prime))
set_orel(toupper(i_prime)-MIN_CHAR,
&($$.label));
if (case_insensitive && isupper(i_prime))
set_orel(tolower(i_prime)-MIN_CHAR,
&($$.label));
}
>>
}
;
atom : << register int i_prime;>>
anychar
<<$$.label = set_of($1.letter);
i_prime = $1.letter + MIN_CHAR;
if (case_insensitive && islower(i_prime))
set_orel(toupper(i_prime)-MIN_CHAR,
&($$.label));
if (case_insensitive && isupper(i_prime))
set_orel(tolower(i_prime)-MIN_CHAR,
&($$.label));
>>
;
anychar : REGCHAR <<$$.letter = $1.letter - MIN_CHAR;>>
| OCTAL_VALUE <<$$.letter = $1.letter - MIN_CHAR;>>
| HEX_VALUE <<$$.letter = $1.letter - MIN_CHAR;>>
| DEC_VALUE <<$$.letter = $1.letter - MIN_CHAR;>>
| TAB <<$$.letter = $1.letter - MIN_CHAR;>>
| NL <<$$.letter = $1.letter - MIN_CHAR;>>
| CR <<$$.letter = $1.letter - MIN_CHAR;>>
| BS <<$$.letter = $1.letter - MIN_CHAR;>>
| LIT <<$$.letter = $1.letter - MIN_CHAR;>>
/* NOTE: LEX_EOF is ALWAYS shifted to 0 = MIN_CHAR - MIN_CHAR*/
| L_EOF <<$$.letter = 0;>>
;
<</* empty action */>>
#lexclass ACT
#token "@" << error("unterminated action", zzline); zzmode(START); >>
#token ACTION "\>\>"
<< if (func_action) fprintf(OUT,"}\n\n");
zzmode(START);
>>
#token "\>" << putc(zzlextext[0], OUT); zzskip(); >>
#token "\\\>" << putc('>', OUT); zzskip(); >>
#token "\\" << putc('\\', OUT); zzskip(); >>
#token "\n" << putc(zzlextext[0], OUT); ++zzline; zzskip(); >>
#token "~[\>\\@\n]+" << fprintf(OUT, "%s", &(zzlextext[0])); zzskip(); >>
<<
/* finds nfa state i in the binary tree nfa_array */
nfa_node *index_nfa(i)
register int i;
{
register nfa_node *p = nfa_array;
if (i){
while((i>1) && p){
if(i & 1)
p = p->right;
else
p = p->left;
i = i\>\>1;
}
return p;
}else{
return NIL_INDEX;
}
}
/* adds a new nfa to the binary tree and returns a pointer to it */
nfa_node *new_nfa_node()
{
register nfa_node *p = nfa_array;
nfa_node *t;
register int i;
i = ++nfa_allocated;
t = (nfa_node*) malloc(sizeof(nfa_node));
*t = nfa_model_node;
t->node_no = i;
while((i>3) && p){
if(i & 1)
p = p->right;
else
p = p->left;
i = i\>\>1;
}
if (nfa_allocated == 1)
nfa_array = t;
else if (p != NIL_INDEX){
if (i & 1)
p->right = t;
else
p->left = t;
}
else{
internal_error("%s(%d): missing node on binary tree\n",
__FILE__,__LINE__);
}
return t;
}
/* initialize the model node used to fill in newly made nfa_nodes */
make_nfa_model_node()
{
nfa_model_node.left = NULL;
nfa_model_node.right = NULL;
nfa_model_node.node_no = -1; /* impossible value for real nfa node */
nfa_model_node.nfa_set = 0;
nfa_model_node.accept = 0; /* error state default*/
nfa_model_node.trans[0] = NULL;
nfa_model_node.trans[1] = NULL;
nfa_model_node.label = empty;
}
>>