wireshark/tools/lemon/lemon.c

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/*
** Copyright (c) 1991, 1994, 1997, 1998 D. Richard Hipp
**
** This file contains all sources (including headers) to the LEMON
** LALR(1) parser generator. The sources have been combined into a
** single file to make it easy to include LEMON as part of another
** program.
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public
** License as published by the Free Software Foundation; either
** version 2 of the License, or (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
** General Public License for more details.
**
** You should have received a copy of the GNU General Public
** License along with this library; if not, write to the
** Free Software Foundation, Inc., 59 Temple Place - Suite 330,
** Boston, MA 02111-1307, USA.
**
** Author contact information:
** drh@acm.org
** http://www.hwaci.com/drh/
**
** $Id: lemon.c,v 1.3 2001/02/15 06:01:23 guy Exp $
*/
#include <stdio.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
/*
* Wrapper around "isupper()", "islower()", etc. to cast the argument to
* "unsigned char", so that they at least handle non-ASCII 8-bit characters
* (and don't provoke a pile of warnings from GCC).
*/
#define safe_isupper(c) isupper((unsigned char)(c))
#define safe_islower(c) islower((unsigned char)(c))
#define safe_isalpha(c) isalpha((unsigned char)(c))
#define safe_isalnum(c) isalnum((unsigned char)(c))
#define safe_isspace(c) isspace((unsigned char)(c))
extern int access(const char *, int);
#ifndef __WIN32__
# if defined(_WIN32) || defined(WIN32)
# define __WIN32__
# endif
#endif
/* #define PRIVATE static */
#define PRIVATE
#ifdef TEST
#define MAXRHS 5 /* Set low to exercise exception code */
#else
#define MAXRHS 1000
#endif
char *msort(char *, char **, int (*)(void *, void *));
/********** From the file "struct.h" *************************************/
/*
** Principal data structures for the LEMON parser generator.
*/
typedef enum {FALSE=0, TRUE} Boolean;
/* Symbols (terminals and nonterminals) of the grammar are stored
** in the following: */
struct symbol {
char *name; /* Name of the symbol */
int index; /* Index number for this symbol */
enum {
TERMINAL,
NONTERMINAL
} type; /* Symbols are all either TERMINALS or NTs */
struct rule *rule; /* Linked list of rules of this (if an NT) */
int prec; /* Precedence if defined (-1 otherwise) */
enum e_assoc {
LEFT,
RIGHT,
NONE,
UNK
} assoc; /* Associativity if predecence is defined */
char *firstset; /* First-set for all rules of this symbol */
Boolean lambda; /* True if NT and can generate an empty string */
char *destructor; /* Code which executes whenever this symbol is
** popped from the stack during error processing */
int destructorln; /* Line number of destructor code */
char *datatype; /* The data type of information held by this
** object. Only used if type==NONTERMINAL */
int dtnum; /* The data type number. In the parser, the value
** stack is a union. The .yy%d element of this
** union is the correct data type for this object */
};
/* Each production rule in the grammar is stored in the following
** structure. */
struct rule {
struct symbol *lhs; /* Left-hand side of the rule */
char *lhsalias; /* Alias for the LHS (NULL if none) */
int ruleline; /* Line number for the rule */
int nrhs; /* Number of RHS symbols */
struct symbol **rhs; /* The RHS symbols */
char **rhsalias; /* An alias for each RHS symbol (NULL if none) */
int line; /* Line number at which code begins */
char *code; /* The code executed when this rule is reduced */
struct symbol *precsym; /* Precedence symbol for this rule */
int index; /* An index number for this rule */
Boolean canReduce; /* True if this rule is ever reduced */
struct rule *nextlhs; /* Next rule with the same LHS */
struct rule *next; /* Next rule in the global list */
};
/* A configuration is a production rule of the grammar together with
** a mark (dot) showing how much of that rule has been processed so far.
** Configurations also contain a follow-set which is a list of terminal
** symbols which are allowed to immediately follow the end of the rule.
** Every configuration is recorded as an instance of the following: */
struct config {
struct rule *rp; /* The rule upon which the configuration is based */
int dot; /* The parse point */
char *fws; /* Follow-set for this configuration only */
struct plink *fplp; /* Follow-set forward propagation links */
struct plink *bplp; /* Follow-set backwards propagation links */
struct state *stp; /* Pointer to state which contains this */
enum {
COMPLETE, /* The status is used during followset and */
INCOMPLETE /* shift computations */
} status;
struct config *next; /* Next configuration in the state */
struct config *bp; /* The next basis configuration */
};
/* Every shift or reduce operation is stored as one of the following */
struct action {
struct symbol *sp; /* The look-ahead symbol */
enum e_action {
SHIFT,
ACCEPT,
REDUCE,
ERROR,
CONFLICT, /* Was a reduce, but part of a conflict */
SH_RESOLVED, /* Was a shift. Precedence resolved conflict */
RD_RESOLVED, /* Was reduce. Precedence resolved conflict */
NOT_USED /* Deleted by compression */
} type;
union {
struct state *stp; /* The new state, if a shift */
struct rule *rp; /* The rule, if a reduce */
} x;
struct action *next; /* Next action for this state */
struct action *collide; /* Next action with the same hash */
};
/* Each state of the generated parser's finite state machine
** is encoded as an instance of the following structure. */
struct state {
struct config *bp; /* The basis configurations for this state */
struct config *cfp; /* All configurations in this set */
int index; /* Sequencial number for this state */
struct action *ap; /* Array of actions for this state */
int naction; /* Number of actions for this state */
int tabstart; /* First index of the action table */
int tabdfltact; /* Default action */
};
/* A followset propagation link indicates that the contents of one
** configuration followset should be propagated to another whenever
** the first changes. */
struct plink {
struct config *cfp; /* The configuration to which linked */
struct plink *next; /* The next propagate link */
};
/* The state vector for the entire parser generator is recorded as
** follows. (LEMON uses no global variables and makes little use of
** static variables. Fields in the following structure can be thought
** of as begin global variables in the program.) */
struct lemon {
struct state **sorted; /* Table of states sorted by state number */
struct rule *rule; /* List of all rules */
int nstate; /* Number of states */
int nrule; /* Number of rules */
int nsymbol; /* Number of terminal and nonterminal symbols */
int nterminal; /* Number of terminal symbols */
struct symbol **symbols; /* Sorted array of pointers to symbols */
int errorcnt; /* Number of errors */
struct symbol *errsym; /* The error symbol */
char *name; /* Name of the generated parser */
char *arg; /* Declaration of the 3th argument to parser */
char *tokentype; /* Type of terminal symbols in the parser stack */
char *start; /* Name of the start symbol for the grammar */
char *stacksize; /* Size of the parser stack */
char *include; /* Code to put at the start of the C file */
int includeln; /* Line number for start of include code */
char *error; /* Code to execute when an error is seen */
int errorln; /* Line number for start of error code */
char *overflow; /* Code to execute on a stack overflow */
int overflowln; /* Line number for start of overflow code */
char *failure; /* Code to execute on parser failure */
int failureln; /* Line number for start of failure code */
char *accept; /* Code to execute when the parser excepts */
int acceptln; /* Line number for the start of accept code */
char *extracode; /* Code appended to the generated file */
int extracodeln; /* Line number for the start of the extra code */
char *tokendest; /* Code to execute to destroy token data */
int tokendestln; /* Line number for token destroyer code */
char *filename; /* Name of the input file */
char *basename; /* Basename of inputer file (no directory or path */
char *outname; /* Name of the current output file */
char *outdirname; /* Name of the output directory, specified by user */
char *templatename; /* Name of template file to use, specified by user */
char *tokenprefix; /* A prefix added to token names in the .h file */
int nconflict; /* Number of parsing conflicts */
int tablesize; /* Size of the parse tables */
int basisflag; /* Print only basis configurations */
char *argv0; /* Name of the program */
};
#define MemoryCheck(X) if((X)==0){ \
extern void memory_error(void); \
memory_error(); \
}
/******** From the file "action.h" *************************************/
struct action *Action_new(void);
struct action *Action_sort(struct action *);
void Action_add(struct action **, enum e_action, struct symbol *, void *);
/********* From the file "assert.h" ************************************/
void myassert(char *, int);
#ifndef NDEBUG
# define assert(X) if(!(X))myassert(__FILE__,__LINE__)
#else
# define assert(X)
#endif
/********** From the file "build.h" ************************************/
void FindRulePrecedences(struct lemon *);
void FindFirstSets(struct lemon *);
void FindStates(struct lemon *);
void FindLinks(struct lemon *);
void FindFollowSets(struct lemon *);
void FindActions(struct lemon *);
/********* From the file "configlist.h" *********************************/
void Configlist_init(void);
struct config *Configlist_add(struct rule *, int);
struct config *Configlist_addbasis(struct rule *, int);
void Configlist_closure(struct lemon *);
void Configlist_sort(void);
void Configlist_sortbasis(void);
struct config *Configlist_return(void);
struct config *Configlist_basis(void);
void Configlist_eat(struct config *);
void Configlist_reset(void);
/********* From the file "error.h" ***************************************/
void ErrorMsg( char *, int, char *, ... );
/****** From the file "option.h" ******************************************/
struct s_options {
enum { OPT_FLAG=1, OPT_INT, OPT_DBL, OPT_STR,
OPT_FFLAG, OPT_FINT, OPT_FDBL, OPT_FSTR} type;
char *label;
char *arg;
char *message;
};
int optinit(char**,struct s_options*,FILE*);
int optnargs(void);
char *get_optarg(int);
void get_opterr(int);
void optprint(void);
/******** From the file "parse.h" *****************************************/
void Parse(struct lemon *lemp);
/********* From the file "plink.h" ***************************************/
struct plink *Plink_new(void);
void Plink_add(struct plink **, struct config *);
void Plink_copy(struct plink **, struct plink *);
void Plink_delete(struct plink *);
/********** From the file "report.h" *************************************/
void Reprint(struct lemon *);
void ReportOutput(struct lemon *);
void ReportTable(struct lemon *, int);
void ReportHeader(struct lemon *);
void CompressTables(struct lemon *);
/********** From the file "set.h" ****************************************/
void SetSize(int N); /* All sets will be of size N */
char *SetNew(void); /* A new set for element 0..N */
void SetFree(char*); /* Deallocate a set */
int SetAdd(char*,int); /* Add element to a set */
int SetUnion(char *A,char *B); /* A <- A U B, thru element N */
#define SetFind(X,Y) (X[Y]) /* True if Y is in set X */
/**************** From the file "table.h" *********************************/
/*
** All code in this file has been automatically generated
** from a specification in the file
** "table.q"
** by the associative array code building program "aagen".
** Do not edit this file! Instead, edit the specification
** file, then rerun aagen.
*/
/*
** Code for processing tables in the LEMON parser generator.
*/
/* Routines for handling a strings */
char *Strsafe(char *);
void Strsafe_init(void);
int Strsafe_insert(char *);
char *Strsafe_find(char *);
/* Routines for handling symbols of the grammar */
struct symbol *Symbol_new(char *x);
int Symbolcmpp(struct symbol **, struct symbol **);
void Symbol_init(void);
int Symbol_insert(struct symbol *, char *);
struct symbol *Symbol_find(char *);
struct symbol *Symbol_Nth(int);
int Symbol_count(void);
struct symbol **Symbol_arrayof(void);
/* Routines to manage the state table */
int Configcmp(void *, void *);
struct state *State_new(void);
void State_init(void);
int State_insert(struct state *, struct config *);
struct state *State_find(struct config *);
struct state **State_arrayof(void);
/* Routines used for efficiency in Configlist_add */
void Configtable_init(void);
int Configtable_insert(struct config *);
struct config *Configtable_find(struct config *);
void Configtable_clear(int(*)(struct config *));
/****************** From the file "action.c" *******************************/
/*
** Routines processing parser actions in the LEMON parser generator.
*/
/* Allocate a new parser action */
struct action *Action_new(void){
static struct action *freelist = 0;
struct action *new;
if( freelist==0 ){
int i;
int amt = 100;
freelist = (struct action *)malloc( sizeof(struct action)*amt );
if( freelist==0 ){
fprintf(stderr,"Unable to allocate memory for a new parser action.");
exit(1);
}
for(i=0; i<amt-1; i++) freelist[i].next = &freelist[i+1];
freelist[amt-1].next = 0;
}
new = freelist;
freelist = freelist->next;
return new;
}
/* Compare two actions */
static int actioncmp(void *ap1_arg, void *ap2_arg)
{
struct action *ap1 = ap1_arg, *ap2 = ap2_arg;
int rc;
rc = ap1->sp->index - ap2->sp->index;
if( rc==0 ) rc = (int)ap1->type - (int)ap2->type;
if( rc==0 ){
assert( ap1->type==REDUCE && ap2->type==REDUCE );
rc = ap1->x.rp->index - ap2->x.rp->index;
}
return rc;
}
/* Sort parser actions */
struct action *Action_sort(struct action *ap)
{
ap = (struct action *)msort((char *)ap,(char **)&ap->next,actioncmp);
return ap;
}
void Action_add(struct action **app, enum e_action type, struct symbol *sp,
void *arg)
{
struct action *new;
new = Action_new();
new->next = *app;
*app = new;
new->type = type;
new->sp = sp;
if( type==SHIFT ){
new->x.stp = (struct state *)arg;
}else{
new->x.rp = (struct rule *)arg;
}
}
/********************** From the file "assert.c" ****************************/
/*
** A more efficient way of handling assertions.
*/
void myassert(char *file, int line)
{
fprintf(stderr,"Assertion failed on line %d of file \"%s\"\n",line,file);
exit(1);
}
/********************** From the file "build.c" *****************************/
/*
** Routines to construction the finite state machine for the LEMON
** parser generator.
*/
/* Find a precedence symbol of every rule in the grammar.
**
** Those rules which have a precedence symbol coded in the input
** grammar using the "[symbol]" construct will already have the
** rp->precsym field filled. Other rules take as their precedence
** symbol the first RHS symbol with a defined precedence. If there
** are not RHS symbols with a defined precedence, the precedence
** symbol field is left blank.
*/
void FindRulePrecedences(struct lemon *xp)
{
struct rule *rp;
for(rp=xp->rule; rp; rp=rp->next){
if( rp->precsym==0 ){
int i;
for(i=0; i<rp->nrhs; i++){
if( rp->rhs[i]->prec>=0 ){
rp->precsym = rp->rhs[i];
break;
}
}
}
}
return;
}
/* Find all nonterminals which will generate the empty string.
** Then go back and compute the first sets of every nonterminal.
** The first set is the set of all terminal symbols which can begin
** a string generated by that nonterminal.
*/
void FindFirstSets(struct lemon *lemp)
{
int i;
struct rule *rp;
int progress;
for(i=0; i<lemp->nsymbol; i++){
lemp->symbols[i]->lambda = FALSE;
}
for(i=lemp->nterminal; i<lemp->nsymbol; i++){
lemp->symbols[i]->firstset = SetNew();
}
/* First compute all lambdas */
do{
progress = 0;
for(rp=lemp->rule; rp; rp=rp->next){
if( rp->lhs->lambda ) continue;
for(i=0; i<rp->nrhs; i++){
if( rp->rhs[i]->lambda==FALSE ) break;
}
if( i==rp->nrhs ){
rp->lhs->lambda = TRUE;
progress = 1;
}
}
}while( progress );
/* Now compute all first sets */
do{
struct symbol *s1, *s2;
progress = 0;
for(rp=lemp->rule; rp; rp=rp->next){
s1 = rp->lhs;
for(i=0; i<rp->nrhs; i++){
s2 = rp->rhs[i];
if( s2->type==TERMINAL ){
progress += SetAdd(s1->firstset,s2->index);
break;
}else if( s1==s2 ){
if( s1->lambda==FALSE ) break;
}else{
progress += SetUnion(s1->firstset,s2->firstset);
if( s2->lambda==FALSE ) break;
}
}
}
}while( progress );
return;
}
/* Compute all LR(0) states for the grammar. Links
** are added to between some states so that the LR(1) follow sets
** can be computed later.
*/
PRIVATE struct state *getstate(struct lemon *); /* forward reference */
void FindStates(lemp)
struct lemon *lemp;
{
struct symbol *sp;
struct rule *rp;
Configlist_init();
/* Find the start symbol */
if( lemp->start ){
sp = Symbol_find(lemp->start);
if( sp==0 ){
ErrorMsg(lemp->filename,0,
"The specified start symbol \"%s\" is not \
in a nonterminal of the grammar. \"%s\" will be used as the start \
symbol instead.",lemp->start,lemp->rule->lhs->name);
lemp->errorcnt++;
sp = lemp->rule->lhs;
}
}else{
sp = lemp->rule->lhs;
}
/* Make sure the start symbol doesn't occur on the right-hand side of
** any rule. Report an error if it does. (YACC would generate a new
** start symbol in this case.) */
for(rp=lemp->rule; rp; rp=rp->next){
int i;
for(i=0; i<rp->nrhs; i++){
if( rp->rhs[i]==sp ){
ErrorMsg(lemp->filename,0,
"The start symbol \"%s\" occurs on the \
right-hand side of a rule. This will result in a parser which \
does not work properly.",sp->name);
lemp->errorcnt++;
}
}
}
/* The basis configuration set for the first state
** is all rules which have the start symbol as their
** left-hand side */
for(rp=sp->rule; rp; rp=rp->nextlhs){
struct config *newcfp;
newcfp = Configlist_addbasis(rp,0);
SetAdd(newcfp->fws,0);
}
/* Compute the first state. All other states will be
** computed automatically during the computation of the first one.
** The returned pointer to the first state is not used. */
(void)getstate(lemp);
return;
}
/* Return a pointer to a state which is described by the configuration
** list which has been built from calls to Configlist_add.
*/
PRIVATE void buildshifts(struct lemon *, struct state *); /* Forwd ref */
PRIVATE struct state *getstate(struct lemon *lemp)
{
struct config *cfp, *bp;
struct state *stp;
/* Extract the sorted basis of the new state. The basis was constructed
** by prior calls to "Configlist_addbasis()". */
Configlist_sortbasis();
bp = Configlist_basis();
/* Get a state with the same basis */
stp = State_find(bp);
if( stp ){
/* A state with the same basis already exists! Copy all the follow-set
** propagation links from the state under construction into the
** preexisting state, then return a pointer to the preexisting state */
struct config *x, *y;
for(x=bp, y=stp->bp; x && y; x=x->bp, y=y->bp){
Plink_copy(&y->bplp,x->bplp);
Plink_delete(x->fplp);
x->fplp = x->bplp = 0;
}
cfp = Configlist_return();
Configlist_eat(cfp);
}else{
/* This really is a new state. Construct all the details */
Configlist_closure(lemp); /* Compute the configuration closure */
Configlist_sort(); /* Sort the configuration closure */
cfp = Configlist_return(); /* Get a pointer to the config list */
stp = State_new(); /* A new state structure */
MemoryCheck(stp);
stp->bp = bp; /* Remember the configuration basis */
stp->cfp = cfp; /* Remember the configuration closure */
stp->index = lemp->nstate++; /* Every state gets a sequence number */
stp->ap = 0; /* No actions, yet. */
State_insert(stp,stp->bp); /* Add to the state table */
buildshifts(lemp,stp); /* Recursively compute successor states */
}
return stp;
}
/* Construct all successor states to the given state. A "successor"
** state is any state which can be reached by a shift action.
*/
PRIVATE void buildshifts(
struct lemon *lemp,
struct state *stp) /* The state from which successors are computed */
{
struct config *cfp; /* For looping thru the config closure of "stp" */
struct config *bcfp; /* For the inner loop on config closure of "stp" */
struct config *new; /* */
struct symbol *sp; /* Symbol following the dot in configuration "cfp" */
struct symbol *bsp; /* Symbol following the dot in configuration "bcfp" */
struct state *newstp; /* A pointer to a successor state */
/* Each configuration becomes complete after it contibutes to a successor
** state. Initially, all configurations are incomplete */
for(cfp=stp->cfp; cfp; cfp=cfp->next) cfp->status = INCOMPLETE;
/* Loop through all configurations of the state "stp" */
for(cfp=stp->cfp; cfp; cfp=cfp->next){
if( cfp->status==COMPLETE ) continue; /* Already used by inner loop */
if( cfp->dot>=cfp->rp->nrhs ) continue; /* Can't shift this config */
Configlist_reset(); /* Reset the new config set */
sp = cfp->rp->rhs[cfp->dot]; /* Symbol after the dot */
/* For every configuration in the state "stp" which has the symbol "sp"
** following its dot, add the same configuration to the basis set under
** construction but with the dot shifted one symbol to the right. */
for(bcfp=cfp; bcfp; bcfp=bcfp->next){
if( bcfp->status==COMPLETE ) continue; /* Already used */
if( bcfp->dot>=bcfp->rp->nrhs ) continue; /* Can't shift this one */
bsp = bcfp->rp->rhs[bcfp->dot]; /* Get symbol after dot */
if( bsp!=sp ) continue; /* Must be same as for "cfp" */
bcfp->status = COMPLETE; /* Mark this config as used */
new = Configlist_addbasis(bcfp->rp,bcfp->dot+1);
Plink_add(&new->bplp,bcfp);
}
/* Get a pointer to the state described by the basis configuration set
** constructed in the preceding loop */
newstp = getstate(lemp);
/* The state "newstp" is reached from the state "stp" by a shift action
** on the symbol "sp" */
Action_add(&stp->ap,SHIFT,sp,newstp);
}
}
/*
** Construct the propagation links
*/
void FindLinks(struct lemon *lemp)
{
int i;
struct config *cfp, *other;
struct state *stp;
struct plink *plp;
/* Housekeeping detail:
** Add to every propagate link a pointer back to the state to
** which the link is attached. */
for(i=0; i<lemp->nstate; i++){
stp = lemp->sorted[i];
for(cfp=stp->cfp; cfp; cfp=cfp->next){
cfp->stp = stp;
}
}
/* Convert all backlinks into forward links. Only the forward
** links are used in the follow-set computation. */
for(i=0; i<lemp->nstate; i++){
stp = lemp->sorted[i];
for(cfp=stp->cfp; cfp; cfp=cfp->next){
for(plp=cfp->bplp; plp; plp=plp->next){
other = plp->cfp;
Plink_add(&other->fplp,cfp);
}
}
}
}
/* Compute all followsets.
**
** A followset is the set of all symbols which can come immediately
** after a configuration.
*/
void FindFollowSets(struct lemon *lemp)
{
int i;
struct config *cfp;
struct plink *plp;
int progress;
int change;
for(i=0; i<lemp->nstate; i++){
for(cfp=lemp->sorted[i]->cfp; cfp; cfp=cfp->next){
cfp->status = INCOMPLETE;
}
}
do{
progress = 0;
for(i=0; i<lemp->nstate; i++){
for(cfp=lemp->sorted[i]->cfp; cfp; cfp=cfp->next){
if( cfp->status==COMPLETE ) continue;
for(plp=cfp->fplp; plp; plp=plp->next){
change = SetUnion(plp->cfp->fws,cfp->fws);
if( change ){
plp->cfp->status = INCOMPLETE;
progress = 1;
}
}
cfp->status = COMPLETE;
}
}
}while( progress );
}
static int resolve_conflict(struct action *, struct action *, struct symbol *);
/* Compute the reduce actions, and resolve conflicts.
*/
void FindActions(struct lemon *lemp)
{
int i,j;
struct config *cfp;
struct state *stp;
struct symbol *sp;
struct rule *rp;
/* Add all of the reduce actions
** A reduce action is added for each element of the followset of
** a configuration which has its dot at the extreme right.
*/
for(i=0; i<lemp->nstate; i++){ /* Loop over all states */
stp = lemp->sorted[i];
for(cfp=stp->cfp; cfp; cfp=cfp->next){ /* Loop over all configurations */
if( cfp->rp->nrhs==cfp->dot ){ /* Is dot at extreme right? */
for(j=0; j<lemp->nterminal; j++){
if( SetFind(cfp->fws,j) ){
/* Add a reduce action to the state "stp" which will reduce by the
** rule "cfp->rp" if the lookahead symbol is "lemp->symbols[j]" */
Action_add(&stp->ap,REDUCE,lemp->symbols[j],cfp->rp);
}
}
}
}
}
/* Add the accepting token */
if( lemp->start ){
sp = Symbol_find(lemp->start);
if( sp==0 ) sp = lemp->rule->lhs;
}else{
sp = lemp->rule->lhs;
}
/* Add to the first state (which is always the starting state of the
** finite state machine) an action to ACCEPT if the lookahead is the
** start nonterminal. */
Action_add(&lemp->sorted[0]->ap,ACCEPT,sp,0);
/* Resolve conflicts */
for(i=0; i<lemp->nstate; i++){
struct action *ap, *nap;
struct state *stp;
stp = lemp->sorted[i];
assert( stp->ap );
stp->ap = Action_sort(stp->ap);
for(ap=stp->ap; ap && ap->next; ap=nap){
for(nap=ap->next; nap && nap->sp==ap->sp; nap=nap->next){
/* The two actions "ap" and "nap" have the same lookahead.
** Figure out which one should be used */
lemp->nconflict += resolve_conflict(ap,nap,lemp->errsym);
}
}
}
/* Report an error for each rule that can never be reduced. */
for(rp=lemp->rule; rp; rp=rp->next) rp->canReduce = FALSE;
for(i=0; i<lemp->nstate; i++){
struct action *ap;
for(ap=lemp->sorted[i]->ap; ap; ap=ap->next){
if( ap->type==REDUCE ) ap->x.rp->canReduce = TRUE;
}
}
for(rp=lemp->rule; rp; rp=rp->next){
if( rp->canReduce ) continue;
ErrorMsg(lemp->filename,rp->ruleline,"This rule can not be reduced.\n");
lemp->errorcnt++;
}
}
/* Resolve a conflict between the two given actions. If the
** conflict can't be resolve, return non-zero.
**
** NO LONGER TRUE:
** To resolve a conflict, first look to see if either action
** is on an error rule. In that case, take the action which
** is not associated with the error rule. If neither or both
** actions are associated with an error rule, then try to
** use precedence to resolve the conflict.
**
** If either action is a SHIFT, then it must be apx. This
** function won't work if apx->type==REDUCE and apy->type==SHIFT.
*/
static int resolve_conflict(
struct action *apx,
struct action *apy,
struct symbol *errsym) /* The error symbol (if defined. NULL otherwise) */
{
struct symbol *spx, *spy;
int errcnt = 0;
assert( apx->sp==apy->sp ); /* Otherwise there would be no conflict */
if( apx->type==SHIFT && apy->type==REDUCE ){
spx = apx->sp;
spy = apy->x.rp->precsym;
if( spy==0 || spx->prec<0 || spy->prec<0 ){
/* Not enough precedence information. */
apy->type = CONFLICT;
errcnt++;
}else if( spx->prec>spy->prec ){ /* Lower precedence wins */
apy->type = RD_RESOLVED;
}else if( spx->prec<spy->prec ){
apx->type = SH_RESOLVED;
}else if( spx->prec==spy->prec && spx->assoc==RIGHT ){ /* Use operator */
apy->type = RD_RESOLVED; /* associativity */
}else if( spx->prec==spy->prec && spx->assoc==LEFT ){ /* to break tie */
apx->type = SH_RESOLVED;
}else{
assert( spx->prec==spy->prec && spx->assoc==NONE );
apy->type = CONFLICT;
errcnt++;
}
}else if( apx->type==REDUCE && apy->type==REDUCE ){
spx = apx->x.rp->precsym;
spy = apy->x.rp->precsym;
if( spx==0 || spy==0 || spx->prec<0 ||
spy->prec<0 || spx->prec==spy->prec ){
apy->type = CONFLICT;
errcnt++;
}else if( spx->prec>spy->prec ){
apy->type = RD_RESOLVED;
}else if( spx->prec<spy->prec ){
apx->type = RD_RESOLVED;
}
}else{
/* Can't happen. Shifts have to come before Reduces on the
** list because the reduces were added last. Hence, if apx->type==REDUCE
** then it is impossible for apy->type==SHIFT */
}
return errcnt;
}
/********************* From the file "configlist.c" *************************/
/*
** Routines to processing a configuration list and building a state
** in the LEMON parser generator.
*/
static struct config *freelist = 0; /* List of free configurations */
static struct config *current = 0; /* Top of list of configurations */
static struct config **currentend = 0; /* Last on list of configs */
static struct config *basis = 0; /* Top of list of basis configs */
static struct config **basisend = 0; /* End of list of basis configs */
/* Return a pointer to a new configuration */
PRIVATE struct config *newconfig(void){
struct config *new;
if( freelist==0 ){
int i;
int amt = 3;
freelist = (struct config *)malloc( sizeof(struct config)*amt );
if( freelist==0 ){
fprintf(stderr,"Unable to allocate memory for a new configuration.");
exit(1);
}
for(i=0; i<amt-1; i++) freelist[i].next = &freelist[i+1];
freelist[amt-1].next = 0;
}
new = freelist;
freelist = freelist->next;
return new;
}
/* The configuration "old" is no longer used */
PRIVATE void deleteconfig(struct config *old)
{
old->next = freelist;
freelist = old;
}
/* Initialized the configuration list builder */
void Configlist_init(void){
current = 0;
currentend = &current;
basis = 0;
basisend = &basis;
Configtable_init();
return;
}
/* Initialized the configuration list builder */
void Configlist_reset(void){
current = 0;
currentend = &current;
basis = 0;
basisend = &basis;
Configtable_clear(0);
return;
}
/* Add another configuration to the configuration list */
struct config *Configlist_add(
struct rule *rp, /* The rule */
int dot) /* Index into the RHS of the rule where the dot goes */
{
struct config *cfp, model;
assert( currentend!=0 );
model.rp = rp;
model.dot = dot;
cfp = Configtable_find(&model);
if( cfp==0 ){
cfp = newconfig();
cfp->rp = rp;
cfp->dot = dot;
cfp->fws = SetNew();
cfp->stp = 0;
cfp->fplp = cfp->bplp = 0;
cfp->next = 0;
cfp->bp = 0;
*currentend = cfp;
currentend = &cfp->next;
Configtable_insert(cfp);
}
return cfp;
}
/* Add a basis configuration to the configuration list */
struct config *Configlist_addbasis(struct rule *rp, int dot)
{
struct config *cfp, model;
assert( basisend!=0 );
assert( currentend!=0 );
model.rp = rp;
model.dot = dot;
cfp = Configtable_find(&model);
if( cfp==0 ){
cfp = newconfig();
cfp->rp = rp;
cfp->dot = dot;
cfp->fws = SetNew();
cfp->stp = 0;
cfp->fplp = cfp->bplp = 0;
cfp->next = 0;
cfp->bp = 0;
*currentend = cfp;
currentend = &cfp->next;
*basisend = cfp;
basisend = &cfp->bp;
Configtable_insert(cfp);
}
return cfp;
}
/* Compute the closure of the configuration list */
void Configlist_closure(struct lemon *lemp)
{
struct config *cfp, *newcfp;
struct rule *rp, *newrp;
struct symbol *sp, *xsp;
int i, dot;
assert( currentend!=0 );
for(cfp=current; cfp; cfp=cfp->next){
rp = cfp->rp;
dot = cfp->dot;
if( dot>=rp->nrhs ) continue;
sp = rp->rhs[dot];
if( sp->type==NONTERMINAL ){
if( sp->rule==0 && sp!=lemp->errsym ){
ErrorMsg(lemp->filename,rp->line,"Nonterminal \"%s\" has no rules.",
sp->name);
lemp->errorcnt++;
}
for(newrp=sp->rule; newrp; newrp=newrp->nextlhs){
newcfp = Configlist_add(newrp,0);
for(i=dot+1; i<rp->nrhs; i++){
xsp = rp->rhs[i];
if( xsp->type==TERMINAL ){
SetAdd(newcfp->fws,xsp->index);
break;
}else{
SetUnion(newcfp->fws,xsp->firstset);
if( xsp->lambda==FALSE ) break;
}
}
if( i==rp->nrhs ) Plink_add(&cfp->fplp,newcfp);
}
}
}
return;
}
/* Sort the configuration list */
void Configlist_sort(void){
current = (struct config *)msort((char *)current,(char **)&(current->next),Configcmp);
currentend = 0;
return;
}
/* Sort the basis configuration list */
void Configlist_sortbasis(void){
basis = (struct config *)msort((char *)current,(char **)&(current->bp),Configcmp);
basisend = 0;
return;
}
/* Return a pointer to the head of the configuration list and
** reset the list */
struct config *Configlist_return(void){
struct config *old;
old = current;
current = 0;
currentend = 0;
return old;
}
/* Return a pointer to the head of the configuration list and
** reset the list */
struct config *Configlist_basis(void){
struct config *old;
old = basis;
basis = 0;
basisend = 0;
return old;
}
/* Free all elements of the given configuration list */
void Configlist_eat(struct config *cfp)
{
struct config *nextcfp;
for(; cfp; cfp=nextcfp){
nextcfp = cfp->next;
assert( cfp->fplp==0 );
assert( cfp->bplp==0 );
if( cfp->fws ) SetFree(cfp->fws);
deleteconfig(cfp);
}
return;
}
/***************** From the file "error.c" *********************************/
/*
** Code for printing error message.
*/
/* Find a good place to break "msg" so that its length is at least "min"
** but no more than "max". Make the point as close to max as possible.
*/
static int findbreak(char *msg, int min, int max)
{
int i,spot;
char c;
for(i=spot=min; i<=max; i++){
c = msg[i];
if( c=='\t' ) msg[i] = ' ';
if( c=='\n' ){ msg[i] = ' '; spot = i; break; }
if( c==0 ){ spot = i; break; }
if( c=='-' && i<max-1 ) spot = i+1;
if( c==' ' ) spot = i;
}
return spot;
}
/*
** The error message is split across multiple lines if necessary. The
** splits occur at a space, if there is a space available near the end
** of the line.
*/
#define ERRMSGSIZE 10000 /* Hope this is big enough. No way to error check */
#define LINEWIDTH 79 /* Max width of any output line */
#define PREFIXLIMIT 30 /* Max width of the prefix on each line */
void ErrorMsg(char *filename, int lineno, char *format, ...)
{
char errmsg[ERRMSGSIZE];
char prefix[PREFIXLIMIT+10];
int errmsgsize;
int prefixsize;
int availablewidth;
va_list ap;
int end, restart, base;
va_start(ap, format);
/* Prepare a prefix to be prepended to every output line */
if( lineno>0 ){
sprintf(prefix,"%.*s:%d: ",PREFIXLIMIT-10,filename,lineno);
}else{
sprintf(prefix,"%.*s: ",PREFIXLIMIT-10,filename);
}
prefixsize = strlen(prefix);
availablewidth = LINEWIDTH - prefixsize;
/* Generate the error message */
vsprintf(errmsg,format,ap);
va_end(ap);
errmsgsize = strlen(errmsg);
/* Remove trailing '\n's from the error message. */
while( errmsgsize>0 && errmsg[errmsgsize-1]=='\n' ){
errmsg[--errmsgsize] = 0;
}
/* Print the error message */
base = 0;
while( errmsg[base]!=0 ){
end = restart = findbreak(&errmsg[base],0,availablewidth);
restart += base;
while( errmsg[restart]==' ' ) restart++;
fprintf(stdout,"%s%.*s\n",prefix,end,&errmsg[base]);
base = restart;
}
}
/**************** From the file "main.c" ************************************/
/*
** Main program file for the LEMON parser generator.
*/
/* Report an out-of-memory condition and abort. This function
** is used mostly by the "MemoryCheck" macro in struct.h
*/
void memory_error(void){
fprintf(stderr,"Out of memory. Aborting...\n");
exit(1);
}
/* Locates the basename in a string possibly containing paths,
* including forward-slash and backward-slash delimiters on Windows,
* and allocates a new string containing just the basename.
* Returns the pointer to that string.
*/
PRIVATE char*
make_basename(char* fullname)
{
char *cp;
char *new_string;
/* Find the last forward slash */
cp = strrchr(fullname, '/');
#ifdef WIN32
/* On Windows, if no forward slash was found, look ofr
* backslash also */
if (!cp)
cp = strrchr(fullname, '\\');
#endif
if (!cp) {
new_string = malloc( strlen(fullname) );
strcpy(new_string, fullname);
}
else {
/* skip the slash */
cp++;
new_string = malloc( strlen(cp) );
strcpy(new_string, cp);
}
return new_string;
}
/* The main program. Parse the command line and do it... */
int main(int argc, char **argv)
{
static int version = 0;
static int rpflag = 0;
static int basisflag = 0;
static int compress = 0;
static int quiet = 0;
static int statistics = 0;
static int mhflag = 0;
static char *outdirname = NULL;
static char *templatename = NULL;
static struct s_options options[] = {
{OPT_FLAG, "b", (char*)&basisflag, "Print only the basis in report."},
{OPT_FLAG, "c", (char*)&compress, "Don't compress the action table."},
{OPT_STR, "d", (char*)&outdirname, "Output directory name."},
{OPT_FLAG, "g", (char*)&rpflag, "Print grammar without actions."},
{OPT_FLAG, "m", (char*)&mhflag, "Output a makeheaders compatible file"},
{OPT_FLAG, "q", (char*)&quiet, "(Quiet) Don't print the report file."},
{OPT_FLAG, "s", (char*)&statistics, "Print parser stats to standard output."},
{OPT_STR, "t", (char*)&templatename, "Template file to use."},
{OPT_FLAG, "x", (char*)&version, "Print the version number."},
{OPT_FLAG,0,0,0}
};
int i;
struct lemon lem;
optinit(argv,options,stderr);
if( version ){
printf("Lemon version 1.0\n"
"Copyright 1991-1997 by D. Richard Hipp\n"
"Freely distributable under the GNU Public License.\n"
);
exit(0);
}
if( optnargs()!=1 ){
fprintf(stderr,"Exactly one filename argument is required.\n");
exit(1);
}
lem.errorcnt = 0;
/* Initialize the machine */
Strsafe_init();
Symbol_init();
State_init();
lem.argv0 = argv[0];
lem.filename = get_optarg(0);
lem.basisflag = basisflag;
lem.nconflict = 0;
lem.name = lem.include = lem.arg = lem.tokentype = lem.start = 0;
lem.stacksize = 0;
lem.error = lem.overflow = lem.failure = lem.accept = lem.tokendest =
lem.tokenprefix = lem.outname = lem.extracode = 0;
lem.tablesize = 0;
Symbol_new("$");
lem.errsym = Symbol_new("error");
lem.outdirname = outdirname;
lem.templatename = templatename;
lem.basename = make_basename(lem.filename);
/* Parse the input file */
Parse(&lem);
if( lem.errorcnt ) exit(lem.errorcnt);
if( lem.rule==0 ){
fprintf(stderr,"Empty grammar.\n");
exit(1);
}
/* Count and index the symbols of the grammar */
lem.nsymbol = Symbol_count();
Symbol_new("{default}");
lem.symbols = Symbol_arrayof();
qsort(lem.symbols,lem.nsymbol+1,sizeof(struct symbol*),
(int(*)())Symbolcmpp);
for(i=0; i<=lem.nsymbol; i++) lem.symbols[i]->index = i;
for(i=1; safe_isupper(lem.symbols[i]->name[0]); i++);
lem.nterminal = i;
/* Generate a reprint of the grammar, if requested on the command line */
if( rpflag ){
Reprint(&lem);
}else{
/* Initialize the size for all follow and first sets */
SetSize(lem.nterminal);
/* Find the precedence for every production rule (that has one) */
FindRulePrecedences(&lem);
/* Compute the lambda-nonterminals and the first-sets for every
** nonterminal */
FindFirstSets(&lem);
/* Compute all LR(0) states. Also record follow-set propagation
** links so that the follow-set can be computed later */
lem.nstate = 0;
FindStates(&lem);
lem.sorted = State_arrayof();
/* Tie up loose ends on the propagation links */
FindLinks(&lem);
/* Compute the follow set of every reducible configuration */
FindFollowSets(&lem);
/* Compute the action tables */
FindActions(&lem);
/* Compress the action tables */
if( compress==0 ) CompressTables(&lem);
/* Generate a report of the parser generated. (the "y.output" file) */
if( !quiet ) ReportOutput(&lem);
/* Generate the source code for the parser */
ReportTable(&lem, mhflag);
/* Produce a header file for use by the scanner. (This step is
** omitted if the "-m" option is used because makeheaders will
** generate the file for us.) */
if( !mhflag ) ReportHeader(&lem);
}
if( statistics ){
printf("Parser statistics: %d terminals, %d nonterminals, %d rules\n",
lem.nterminal, lem.nsymbol - lem.nterminal, lem.nrule);
printf(" %d states, %d parser table entries, %d conflicts\n",
lem.nstate, lem.tablesize, lem.nconflict);
}
if( lem.nconflict ){
fprintf(stderr,"%d parsing conflicts.\n",lem.nconflict);
}
exit(lem.errorcnt + lem.nconflict);
}
/******************** From the file "msort.c" *******************************/
/*
** A generic merge-sort program.
**
** USAGE:
** Let "ptr" be a pointer to some structure which is at the head of
** a null-terminated list. Then to sort the list call:
**
** ptr = msort(ptr,&(ptr->next),cmpfnc);
**
** In the above, "cmpfnc" is a pointer to a function which compares
** two instances of the structure and returns an integer, as in
** strcmp. The second argument is a pointer to the pointer to the
** second element of the linked list. This address is used to compute
** the offset to the "next" field within the structure. The offset to
** the "next" field must be constant for all structures in the list.
**
** The function returns a new pointer which is the head of the list
** after sorting.
**
** ALGORITHM:
** Merge-sort.
*/
/*
** Return a pointer to the next structure in the linked list.
*/
#define NEXT(A) (*(char**)(((char *)A)+offset))
/*
** Inputs:
** a: A sorted, null-terminated linked list. (May be null).
** b: A sorted, null-terminated linked list. (May be null).
** cmp: A pointer to the comparison function.
** offset: Offset in the structure to the "next" field.
**
** Return Value:
** A pointer to the head of a sorted list containing the elements
** of both a and b.
**
** Side effects:
** The "next" pointers for elements in the lists a and b are
** changed.
*/
static char *merge(char *a, char *b, int (*cmp)(void *, void *), int offset)
{
char *ptr, *head;
if( a==0 ){
head = b;
}else if( b==0 ){
head = a;
}else{
if( (*cmp)(a,b)<0 ){
ptr = a;
a = NEXT(a);
}else{
ptr = b;
b = NEXT(b);
}
head = ptr;
while( a && b ){
if( (*cmp)(a,b)<0 ){
NEXT(ptr) = a;
ptr = a;
a = NEXT(a);
}else{
NEXT(ptr) = b;
ptr = b;
b = NEXT(b);
}
}
if( a ) NEXT(ptr) = a;
else NEXT(ptr) = b;
}
return head;
}
/*
** Inputs:
** list: Pointer to a singly-linked list of structures.
** next: Pointer to pointer to the second element of the list.
** cmp: A comparison function.
**
** Return Value:
** A pointer to the head of a sorted list containing the elements
** orginally in list.
**
** Side effects:
** The "next" pointers for elements in list are changed.
*/
#define LISTSIZE 30
char *msort(char *list, char **next, int (*cmp)(void *, void *))
{
int offset;
char *ep;
char *set[LISTSIZE];
int i;
offset = (char *)next - (char *)list;
for(i=0; i<LISTSIZE; i++) set[i] = 0;
while( list ){
ep = list;
list = NEXT(list);
NEXT(ep) = 0;
for(i=0; i<LISTSIZE-1 && set[i]!=0; i++){
ep = merge(ep,set[i],cmp,offset);
set[i] = 0;
}
set[i] = ep;
}
ep = 0;
for(i=0; i<LISTSIZE; i++) if( set[i] ) ep = merge(ep,set[i],cmp,offset);
return ep;
}
/************************ From the file "option.c" **************************/
static char **argv;
static struct s_options *op;
static FILE *errstream;
#define ISOPT(X) ((X)[0]=='-'||(X)[0]=='+'||strchr((X),'=')!=0)
/*
** Print the command line with a carrot pointing to the k-th character
** of the n-th field.
*/
static void errline(int n, int k, FILE *err)
{
int spcnt, i;
spcnt = 0;
if( argv[0] ) fprintf(err,"%s",argv[0]);
spcnt = strlen(argv[0]) + 1;
for(i=1; i<n && argv[i]; i++){
fprintf(err," %s",argv[i]);
spcnt += strlen(argv[i]+1);
}
spcnt += k;
for(; argv[i]; i++) fprintf(err," %s",argv[i]);
if( spcnt<20 ){
fprintf(err,"\n%*s^-- here\n",spcnt,"");
}else{
fprintf(err,"\n%*shere --^\n",spcnt-7,"");
}
}
/*
** Return the index of the N-th non-switch argument. Return -1
** if N is out of range.
*/
static int argindex(int n)
{
int i;
int dashdash = 0;
if( argv!=0 && *argv!=0 ){
for(i=1; argv[i]; i++){
if( dashdash || !ISOPT(argv[i]) ){
if( n==0 ) return i;
n--;
}
if( strcmp(argv[i],"--")==0 ) dashdash = 1;
}
}
return -1;
}
static char emsg[] = "Command line syntax error: ";
/*
** Process a flag command line argument.
*/
static int handleflags(int i, FILE *err)
{
int v;
int errcnt = 0;
int j;
for(j=0; op[j].label; j++){
if( strcmp(&argv[i][1],op[j].label)==0 ) break;
}
v = argv[i][0]=='-' ? 1 : 0;
if( op[j].label==0 ){
if( err ){
fprintf(err,"%sundefined option.\n",emsg);
errline(i,1,err);
}
errcnt++;
}else if( op[j].type==OPT_FLAG ){
*((int*)op[j].arg) = v;
}else if( op[j].type==OPT_FFLAG ){
(*(void(*)())(op[j].arg))(v);
}else{
if( err ){
fprintf(err,"%smissing argument on switch.\n",emsg);
errline(i,1,err);
}
errcnt++;
}
return errcnt;
}
/*
** Process a command line switch which has an argument.
*/
static int handleswitch(int i, FILE *err)
{
int lv = 0;
double dv = 0.0;
char *sv = 0, *end;
char *cp;
int j;
int errcnt = 0;
cp = strchr(argv[i],'=');
*cp = 0;
for(j=0; op[j].label; j++){
if( strcmp(argv[i],op[j].label)==0 ) break;
}
*cp = '=';
if( op[j].label==0 ){
if( err ){
fprintf(err,"%sundefined option.\n",emsg);
errline(i,0,err);
}
errcnt++;
}else{
cp++;
switch( op[j].type ){
case OPT_FLAG:
case OPT_FFLAG:
if( err ){
fprintf(err,"%soption requires an argument.\n",emsg);
errline(i,0,err);
}
errcnt++;
break;
case OPT_DBL:
case OPT_FDBL:
dv = strtod(cp,&end);
if( *end ){
if( err ){
fprintf(err,"%sillegal character in floating-point argument.\n",emsg);
errline(i,(int)(end-argv[i]),err);
}
errcnt++;
}
break;
case OPT_INT:
case OPT_FINT:
lv = strtol(cp,&end,0);
if( *end ){
if( err ){
fprintf(err,"%sillegal character in integer argument.\n",emsg);
errline(i,(int)(end-argv[i]),err);
}
errcnt++;
}
break;
case OPT_STR:
case OPT_FSTR:
sv = cp;
break;
}
switch( op[j].type ){
case OPT_FLAG:
case OPT_FFLAG:
break;
case OPT_DBL:
*(double*)(op[j].arg) = dv;
break;
case OPT_FDBL:
(*(void(*)())(op[j].arg))(dv);
break;
case OPT_INT:
*(int*)(op[j].arg) = lv;
break;
case OPT_FINT:
(*(void(*)())(op[j].arg))((int)lv);
break;
case OPT_STR:
*(char**)(op[j].arg) = sv;
break;
case OPT_FSTR:
(*(void(*)())(op[j].arg))(sv);
break;
}
}
return errcnt;
}
int optinit(char **a, struct s_options *o, FILE *err)
{
int errcnt = 0;
argv = a;
op = o;
errstream = err;
if( argv && *argv && op ){
int i;
for(i=1; argv[i]; i++){
if( argv[i][0]=='+' || argv[i][0]=='-' ){
errcnt += handleflags(i,err);
}else if( strchr(argv[i],'=') ){
errcnt += handleswitch(i,err);
}
}
}
if( errcnt>0 ){
fprintf(err,"Valid command line options for \"%s\" are:\n",*a);
optprint();
exit(1);
}
return 0;
}
int optnargs(void){
int cnt = 0;
int dashdash = 0;
int i;
if( argv!=0 && argv[0]!=0 ){
for(i=1; argv[i]; i++){
if( dashdash || !ISOPT(argv[i]) ) cnt++;
if( strcmp(argv[i],"--")==0 ) dashdash = 1;
}
}
return cnt;
}
char *get_optarg(int n)
{
int i;
i = argindex(n);
return i>=0 ? argv[i] : 0;
}
void get_opterr(int n)
{
int i;
i = argindex(n);
if( i>=0 ) errline(i,0,errstream);
}
void optprint(void){
int i;
int max, len;
max = 0;
for(i=0; op[i].label; i++){
len = strlen(op[i].label) + 1;
switch( op[i].type ){
case OPT_FLAG:
case OPT_FFLAG:
break;
case OPT_INT:
case OPT_FINT:
len += 9; /* length of "<integer>" */
break;
case OPT_DBL:
case OPT_FDBL:
len += 6; /* length of "<real>" */
break;
case OPT_STR:
case OPT_FSTR:
len += 8; /* length of "<string>" */
break;
}
if( len>max ) max = len;
}
for(i=0; op[i].label; i++){
switch( op[i].type ){
case OPT_FLAG:
case OPT_FFLAG:
fprintf(errstream," -%-*s %s\n",max,op[i].label,op[i].message);
break;
case OPT_INT:
case OPT_FINT:
fprintf(errstream," %s=<integer>%*s %s\n",op[i].label,
max-strlen(op[i].label)-9,"",op[i].message);
break;
case OPT_DBL:
case OPT_FDBL:
fprintf(errstream," %s=<real>%*s %s\n",op[i].label,
max-strlen(op[i].label)-6,"",op[i].message);
break;
case OPT_STR:
case OPT_FSTR:
fprintf(errstream," %s=<string>%*s %s\n",op[i].label,
max-strlen(op[i].label)-8,"",op[i].message);
break;
}
}
}
/*********************** From the file "parse.c" ****************************/
/*
** Input file parser for the LEMON parser generator.
*/
/* The state of the parser */
struct pstate {
char *filename; /* Name of the input file */
int tokenlineno; /* Linenumber at which current token starts */
int errorcnt; /* Number of errors so far */
char *tokenstart; /* Text of current token */
struct lemon *gp; /* Global state vector */
enum e_state {
INITIALIZE,
WAITING_FOR_DECL_OR_RULE,
WAITING_FOR_DECL_KEYWORD,
WAITING_FOR_DECL_ARG,
WAITING_FOR_PRECEDENCE_SYMBOL,
WAITING_FOR_ARROW,
IN_RHS,
LHS_ALIAS_1,
LHS_ALIAS_2,
LHS_ALIAS_3,
RHS_ALIAS_1,
RHS_ALIAS_2,
PRECEDENCE_MARK_1,
PRECEDENCE_MARK_2,
RESYNC_AFTER_RULE_ERROR,
RESYNC_AFTER_DECL_ERROR,
WAITING_FOR_DESTRUCTOR_SYMBOL,
WAITING_FOR_DATATYPE_SYMBOL
} state; /* The state of the parser */
struct symbol *lhs; /* Left-hand side of current rule */
char *lhsalias; /* Alias for the LHS */
int nrhs; /* Number of right-hand side symbols seen */
struct symbol *rhs[MAXRHS]; /* RHS symbols */
char *alias[MAXRHS]; /* Aliases for each RHS symbol (or NULL) */
struct rule *prevrule; /* Previous rule parsed */
char *declkeyword; /* Keyword of a declaration */
char **declargslot; /* Where the declaration argument should be put */
int *decllnslot; /* Where the declaration linenumber is put */
enum e_assoc declassoc; /* Assign this association to decl arguments */
int preccounter; /* Assign this precedence to decl arguments */
struct rule *firstrule; /* Pointer to first rule in the grammar */
struct rule *lastrule; /* Pointer to the most recently parsed rule */
};
/* Parse a single token */
static void parseonetoken(struct pstate *psp)
{
char *x;
x = Strsafe(psp->tokenstart); /* Save the token permanently */
#if 0
printf("%s:%d: Token=[%s] state=%d\n",psp->filename,psp->tokenlineno,
x,psp->state);
#endif
switch( psp->state ){
case INITIALIZE:
psp->prevrule = 0;
psp->preccounter = 0;
psp->firstrule = psp->lastrule = 0;
psp->gp->nrule = 0;
/* Fall thru to next case */
case WAITING_FOR_DECL_OR_RULE:
if( x[0]=='%' ){
psp->state = WAITING_FOR_DECL_KEYWORD;
}else if( safe_islower(x[0]) ){
psp->lhs = Symbol_new(x);
psp->nrhs = 0;
psp->lhsalias = 0;
psp->state = WAITING_FOR_ARROW;
}else if( x[0]=='{' ){
if( psp->prevrule==0 ){
ErrorMsg(psp->filename,psp->tokenlineno,
"There is not prior rule opon which to attach the code \
fragment which begins on this line.");
psp->errorcnt++;
}else if( psp->prevrule->code!=0 ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Code fragment beginning on this line is not the first \
to follow the previous rule.");
psp->errorcnt++;
}else{
psp->prevrule->line = psp->tokenlineno;
psp->prevrule->code = &x[1];
}
}else if( x[0]=='[' ){
psp->state = PRECEDENCE_MARK_1;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Token \"%s\" should be either \"%%\" or a nonterminal name.",
x);
psp->errorcnt++;
}
break;
case PRECEDENCE_MARK_1:
if( !safe_isupper(x[0]) ){
ErrorMsg(psp->filename,psp->tokenlineno,
"The precedence symbol must be a terminal.");
psp->errorcnt++;
}else if( psp->prevrule==0 ){
ErrorMsg(psp->filename,psp->tokenlineno,
"There is no prior rule to assign precedence \"[%s]\".",x);
psp->errorcnt++;
}else if( psp->prevrule->precsym!=0 ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Precedence mark on this line is not the first \
to follow the previous rule.");
psp->errorcnt++;
}else{
psp->prevrule->precsym = Symbol_new(x);
}
psp->state = PRECEDENCE_MARK_2;
break;
case PRECEDENCE_MARK_2:
if( x[0]!=']' ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Missing \"]\" on precedence mark.");
psp->errorcnt++;
}
psp->state = WAITING_FOR_DECL_OR_RULE;
break;
case WAITING_FOR_ARROW:
if( x[0]==':' && x[1]==':' && x[2]=='=' ){
psp->state = IN_RHS;
}else if( x[0]=='(' ){
psp->state = LHS_ALIAS_1;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Expected to see a \":\" following the LHS symbol \"%s\".",
psp->lhs->name);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}
break;
case LHS_ALIAS_1:
if( safe_isalpha(x[0]) ){
psp->lhsalias = x;
psp->state = LHS_ALIAS_2;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"\"%s\" is not a valid alias for the LHS \"%s\"\n",
x,psp->lhs->name);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}
break;
case LHS_ALIAS_2:
if( x[0]==')' ){
psp->state = LHS_ALIAS_3;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Missing \")\" following LHS alias name \"%s\".",psp->lhsalias);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}
break;
case LHS_ALIAS_3:
if( x[0]==':' && x[1]==':' && x[2]=='=' ){
psp->state = IN_RHS;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Missing \"->\" following: \"%s(%s)\".",
psp->lhs->name,psp->lhsalias);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}
break;
case IN_RHS:
if( x[0]=='.' ){
struct rule *rp;
rp = (struct rule *)malloc( sizeof(struct rule) +
sizeof(struct symbol*)*psp->nrhs + sizeof(char*)*psp->nrhs );
if( rp==0 ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Can't allocate enough memory for this rule.");
psp->errorcnt++;
psp->prevrule = 0;
}else{
int i;
rp->ruleline = psp->tokenlineno;
rp->rhs = (struct symbol**)&rp[1];
rp->rhsalias = (char**)&(rp->rhs[psp->nrhs]);
for(i=0; i<psp->nrhs; i++){
rp->rhs[i] = psp->rhs[i];
rp->rhsalias[i] = psp->alias[i];
}
rp->lhs = psp->lhs;
rp->lhsalias = psp->lhsalias;
rp->nrhs = psp->nrhs;
rp->code = 0;
rp->precsym = 0;
rp->index = psp->gp->nrule++;
rp->nextlhs = rp->lhs->rule;
rp->lhs->rule = rp;
rp->next = 0;
if( psp->firstrule==0 ){
psp->firstrule = psp->lastrule = rp;
}else{
psp->lastrule->next = rp;
psp->lastrule = rp;
}
psp->prevrule = rp;
}
psp->state = WAITING_FOR_DECL_OR_RULE;
}else if( safe_isalpha(x[0]) ){
if( psp->nrhs>=MAXRHS ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Too many symbol on RHS or rule beginning at \"%s\".",
x);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}else{
psp->rhs[psp->nrhs] = Symbol_new(x);
psp->alias[psp->nrhs] = 0;
psp->nrhs++;
}
}else if( x[0]=='(' && psp->nrhs>0 ){
psp->state = RHS_ALIAS_1;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Illegal character on RHS of rule: \"%s\".",x);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}
break;
case RHS_ALIAS_1:
if( safe_isalpha(x[0]) ){
psp->alias[psp->nrhs-1] = x;
psp->state = RHS_ALIAS_2;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"\"%s\" is not a valid alias for the RHS symbol \"%s\"\n",
x,psp->rhs[psp->nrhs-1]->name);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}
break;
case RHS_ALIAS_2:
if( x[0]==')' ){
psp->state = IN_RHS;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Missing \")\" following LHS alias name \"%s\".",psp->lhsalias);
psp->errorcnt++;
psp->state = RESYNC_AFTER_RULE_ERROR;
}
break;
case WAITING_FOR_DECL_KEYWORD:
if( safe_isalpha(x[0]) ){
psp->declkeyword = x;
psp->declargslot = 0;
psp->decllnslot = 0;
psp->state = WAITING_FOR_DECL_ARG;
if( strcmp(x,"name")==0 ){
psp->declargslot = &(psp->gp->name);
}else if( strcmp(x,"include")==0 ){
psp->declargslot = &(psp->gp->include);
psp->decllnslot = &psp->gp->includeln;
}else if( strcmp(x,"code")==0 ){
psp->declargslot = &(psp->gp->extracode);
psp->decllnslot = &psp->gp->extracodeln;
}else if( strcmp(x,"token_destructor")==0 ){
psp->declargslot = &psp->gp->tokendest;
psp->decllnslot = &psp->gp->tokendestln;
}else if( strcmp(x,"token_prefix")==0 ){
psp->declargslot = &psp->gp->tokenprefix;
}else if( strcmp(x,"syntax_error")==0 ){
psp->declargslot = &(psp->gp->error);
psp->decllnslot = &psp->gp->errorln;
}else if( strcmp(x,"parse_accept")==0 ){
psp->declargslot = &(psp->gp->accept);
psp->decllnslot = &psp->gp->acceptln;
}else if( strcmp(x,"parse_failure")==0 ){
psp->declargslot = &(psp->gp->failure);
psp->decllnslot = &psp->gp->failureln;
}else if( strcmp(x,"stack_overflow")==0 ){
psp->declargslot = &(psp->gp->overflow);
psp->decllnslot = &psp->gp->overflowln;
}else if( strcmp(x,"extra_argument")==0 ){
psp->declargslot = &(psp->gp->arg);
}else if( strcmp(x,"token_type")==0 ){
psp->declargslot = &(psp->gp->tokentype);
}else if( strcmp(x,"stack_size")==0 ){
psp->declargslot = &(psp->gp->stacksize);
}else if( strcmp(x,"start_symbol")==0 ){
psp->declargslot = &(psp->gp->start);
}else if( strcmp(x,"left")==0 ){
psp->preccounter++;
psp->declassoc = LEFT;
psp->state = WAITING_FOR_PRECEDENCE_SYMBOL;
}else if( strcmp(x,"right")==0 ){
psp->preccounter++;
psp->declassoc = RIGHT;
psp->state = WAITING_FOR_PRECEDENCE_SYMBOL;
}else if( strcmp(x,"nonassoc")==0 ){
psp->preccounter++;
psp->declassoc = NONE;
psp->state = WAITING_FOR_PRECEDENCE_SYMBOL;
}else if( strcmp(x,"destructor")==0 ){
psp->state = WAITING_FOR_DESTRUCTOR_SYMBOL;
}else if( strcmp(x,"type")==0 ){
psp->state = WAITING_FOR_DATATYPE_SYMBOL;
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Unknown declaration keyword: \"%%%s\".",x);
psp->errorcnt++;
psp->state = RESYNC_AFTER_DECL_ERROR;
}
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Illegal declaration keyword: \"%s\".",x);
psp->errorcnt++;
psp->state = RESYNC_AFTER_DECL_ERROR;
}
break;
case WAITING_FOR_DESTRUCTOR_SYMBOL:
if( !safe_isalpha(x[0]) ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Symbol name missing after %destructor keyword");
psp->errorcnt++;
psp->state = RESYNC_AFTER_DECL_ERROR;
}else{
struct symbol *sp = Symbol_new(x);
psp->declargslot = &sp->destructor;
psp->decllnslot = &sp->destructorln;
psp->state = WAITING_FOR_DECL_ARG;
}
break;
case WAITING_FOR_DATATYPE_SYMBOL:
if( !safe_isalpha(x[0]) ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Symbol name missing after %destructor keyword");
psp->errorcnt++;
psp->state = RESYNC_AFTER_DECL_ERROR;
}else{
struct symbol *sp = Symbol_new(x);
psp->declargslot = &sp->datatype;
psp->decllnslot = 0;
psp->state = WAITING_FOR_DECL_ARG;
}
break;
case WAITING_FOR_PRECEDENCE_SYMBOL:
if( x[0]=='.' ){
psp->state = WAITING_FOR_DECL_OR_RULE;
}else if( safe_isupper(x[0]) ){
struct symbol *sp;
sp = Symbol_new(x);
if( sp->prec>=0 ){
ErrorMsg(psp->filename,psp->tokenlineno,
"Symbol \"%s\" has already be given a precedence.",x);
psp->errorcnt++;
}else{
sp->prec = psp->preccounter;
sp->assoc = psp->declassoc;
}
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Can't assign a precedence to \"%s\".",x);
psp->errorcnt++;
}
break;
case WAITING_FOR_DECL_ARG:
if( (x[0]=='{' || x[0]=='\"' || safe_isalnum(x[0])) ){
if( *(psp->declargslot)!=0 ){
ErrorMsg(psp->filename,psp->tokenlineno,
"The argument \"%s\" to declaration \"%%%s\" is not the first.",
x[0]=='\"' ? &x[1] : x,psp->declkeyword);
psp->errorcnt++;
psp->state = RESYNC_AFTER_DECL_ERROR;
}else{
*(psp->declargslot) = (x[0]=='\"' || x[0]=='{') ? &x[1] : x;
if( psp->decllnslot ) *psp->decllnslot = psp->tokenlineno;
psp->state = WAITING_FOR_DECL_OR_RULE;
}
}else{
ErrorMsg(psp->filename,psp->tokenlineno,
"Illegal argument to %%%s: %s",psp->declkeyword,x);
psp->errorcnt++;
psp->state = RESYNC_AFTER_DECL_ERROR;
}
break;
case RESYNC_AFTER_RULE_ERROR:
/* if( x[0]=='.' ) psp->state = WAITING_FOR_DECL_OR_RULE;
** break; */
case RESYNC_AFTER_DECL_ERROR:
if( x[0]=='.' ) psp->state = WAITING_FOR_DECL_OR_RULE;
if( x[0]=='%' ) psp->state = WAITING_FOR_DECL_KEYWORD;
break;
}
}
/* In spite of its name, this function is really a scanner. It read
** in the entire input file (all at once) then tokenizes it. Each
** token is passed to the function "parseonetoken" which builds all
** the appropriate data structures in the global state vector "gp".
*/
void Parse(struct lemon *gp)
{
struct pstate ps;
FILE *fp;
char *filebuf;
int filesize;
int lineno;
char c;
char *cp, *nextcp;
int startline = 0;
ps.gp = gp;
ps.filename = gp->filename;
ps.errorcnt = 0;
ps.state = INITIALIZE;
/* Begin by reading the input file */
fp = fopen(ps.filename,"rb");
if( fp==0 ){
ErrorMsg(ps.filename,0,"Can't open this file for reading.");
gp->errorcnt++;
return;
}
fseek(fp,0,2);
filesize = ftell(fp);
rewind(fp);
filebuf = (char *)malloc( filesize+1 );
if( filebuf==0 ){
ErrorMsg(ps.filename,0,"Can't allocate %d of memory to hold this file.",
filesize+1);
gp->errorcnt++;
return;
}
if( fread(filebuf,1,filesize,fp)!=filesize ){
ErrorMsg(ps.filename,0,"Can't read in all %d bytes of this file.",
filesize);
free(filebuf);
gp->errorcnt++;
return;
}
fclose(fp);
filebuf[filesize] = 0;
/* Now scan the text of the input file */
lineno = 1;
for(cp=filebuf; (c= *cp)!=0; ){
if( c=='\n' ) lineno++; /* Keep track of the line number */
if( safe_isspace(c) ){ cp++; continue; } /* Skip all white space */
if( c=='/' && cp[1]=='/' ){ /* Skip C++ style comments */
cp+=2;
while( (c= *cp)!=0 && c!='\n' ) cp++;
continue;
}
if( c=='/' && cp[1]=='*' ){ /* Skip C style comments */
cp+=2;
while( (c= *cp)!=0 && (c!='/' || cp[-1]!='*') ){
if( c=='\n' ) lineno++;
cp++;
}
if( c ) cp++;
continue;
}
ps.tokenstart = cp; /* Mark the beginning of the token */
ps.tokenlineno = lineno; /* Linenumber on which token begins */
if( c=='\"' ){ /* String literals */
cp++;
while( (c= *cp)!=0 && c!='\"' ){
if( c=='\n' ) lineno++;
cp++;
}
if( c==0 ){
ErrorMsg(ps.filename,startline,
"String starting on this line is not terminated before the end of the file.");
ps.errorcnt++;
nextcp = cp;
}else{
nextcp = cp+1;
}
}else if( c=='{' ){ /* A block of C code */
int level;
cp++;
for(level=1; (c= *cp)!=0 && (level>1 || c!='}'); cp++){
if( c=='\n' ) lineno++;
else if( c=='{' ) level++;
else if( c=='}' ) level--;
else if( c=='/' && cp[1]=='*' ){ /* Skip comments */
char prevc;
cp = &cp[2];
prevc = 0;
while( (c= *cp)!=0 && (c!='/' || prevc!='*') ){
if( c=='\n' ) lineno++;
prevc = c;
cp++;
}
}else if( c=='/' && cp[1]=='/' ){ /* Skip C++ style comments too */
cp = &cp[2];
while( (c= *cp)!=0 && c!='\n' ) cp++;
if( c ) lineno++;
}else if( c=='\'' || c=='\"' ){ /* String a character literals */
char startchar, prevc;
startchar = c;
prevc = 0;
for(cp++; (c= *cp)!=0 && (c!=startchar || prevc=='\\'); cp++){
if( c=='\n' ) lineno++;
if( prevc=='\\' ) prevc = 0;
else prevc = c;
}
}
}
if( c==0 ){
ErrorMsg(ps.filename,startline,
"C code starting on this line is not terminated before the end of the file.");
ps.errorcnt++;
nextcp = cp;
}else{
nextcp = cp+1;
}
}else if( safe_isalnum(c) ){ /* Identifiers */
while( (c= *cp)!=0 && (safe_isalnum(c) || c=='_') ) cp++;
nextcp = cp;
}else if( c==':' && cp[1]==':' && cp[2]=='=' ){ /* The operator "::=" */
cp += 3;
nextcp = cp;
}else{ /* All other (one character) operators */
cp++;
nextcp = cp;
}
c = *cp;
*cp = 0; /* Null terminate the token */
parseonetoken(&ps); /* Parse the token */
*cp = c; /* Restore the buffer */
cp = nextcp;
}
free(filebuf); /* Release the buffer after parsing */
gp->rule = ps.firstrule;
gp->errorcnt = ps.errorcnt;
}
/*************************** From the file "plink.c" *********************/
/*
** Routines processing configuration follow-set propagation links
** in the LEMON parser generator.
*/
static struct plink *plink_freelist = 0;
/* Allocate a new plink */
struct plink *Plink_new(void){
struct plink *new;
if( plink_freelist==0 ){
int i;
int amt = 100;
plink_freelist = (struct plink *)malloc( sizeof(struct plink)*amt );
if( plink_freelist==0 ){
fprintf(stderr,
"Unable to allocate memory for a new follow-set propagation link.\n");
exit(1);
}
for(i=0; i<amt-1; i++) plink_freelist[i].next = &plink_freelist[i+1];
plink_freelist[amt-1].next = 0;
}
new = plink_freelist;
plink_freelist = plink_freelist->next;
return new;
}
/* Add a plink to a plink list */
void Plink_add(struct plink **plpp, struct config *cfp)
{
struct plink *new;
new = Plink_new();
new->next = *plpp;
*plpp = new;
new->cfp = cfp;
}
/* Transfer every plink on the list "from" to the list "to" */
void Plink_copy(struct plink **to, struct plink *from)
{
struct plink *nextpl;
while( from ){
nextpl = from->next;
from->next = *to;
*to = from;
from = nextpl;
}
}
/* Delete every plink on the list */
void Plink_delete(struct plink *plp)
{
struct plink *nextpl;
while( plp ){
nextpl = plp->next;
plp->next = plink_freelist;
plink_freelist = plp;
plp = nextpl;
}
}
/*********************** From the file "report.c" **************************/
/*
** Procedures for generating reports and tables in the LEMON parser generator.
*/
/* Generate a filename with the given suffix. Space to hold the
** name comes from malloc() and must be freed by the calling
** function.
*/
PRIVATE char *file_makename(char *pattern, char *suffix)
{
char *name;
char *cp;
name = malloc( strlen(pattern) + strlen(suffix) + 5 );
if( name==0 ){
fprintf(stderr,"Can't allocate space for a filename.\n");
exit(1);
}
strcpy(name,pattern);
cp = strrchr(name,'.');
if( cp ) *cp = 0;
strcat(name,suffix);
return name;
}
/* Generate a filename with the given suffix. Uses only
** the basename of the input file, not the entire path. This
** is useful for creating output files when using outdirname.
** Space to hold this name comes from malloc() and must be
** freed by the calling function.
*/
PRIVATE char *file_makename_using_basename(struct lemon *lemp, char *suffix)
{
return file_makename(lemp->basename, suffix);
}
/* Open a file with a name based on the name of the input file,
** but with a different (specified) suffix, and return a pointer
** to the stream. Prepend outdirname for both reads and writes, because
** the only time we read is when checking for an already-produced
** header file, which should exist in the output directory, not the
** input directory. If we ever need to file_open(,,"r") on the input
** side, we should add another arg to file_open() indicating which
** directory, ("input, "output", or "other") we should deal with.
*/
PRIVATE FILE *file_open(struct lemon *lemp, char *suffix, char *mode)
{
FILE *fp;
char *name;
if( lemp->outname ) free(lemp->outname);
name = file_makename_using_basename(lemp, suffix);
if ( lemp->outdirname != NULL ) {
lemp->outname = malloc( strlen(lemp->outdirname) + strlen(name) + 2);
if ( lemp->outname == 0 ) {
fprintf(stderr, "Can't allocate space for dir/filename");
exit(1);
}
strcpy(lemp->outname, lemp->outdirname);
#ifdef __WIN32__
strcat(lemp->outname, "\\");
#else
strcat(lemp->outname, "/");
#endif
strcat(lemp->outname, name);
free(name);
}
else {
lemp->outname = name;
}
fp = fopen(lemp->outname,mode);
if( fp==0 && *mode=='w' ){
fprintf(stderr,"Can't open file \"%s\".\n",lemp->outname);
lemp->errorcnt++;
return 0;
}
return fp;
}
/* Duplicate the input file without comments and without actions
** on rules */
void Reprint(struct lemon *lemp)
{
struct rule *rp;
struct symbol *sp;
int i, j, maxlen, len, ncolumns, skip;
printf("// Reprint of input file \"%s\".\n// Symbols:\n",lemp->filename);
maxlen = 10;
for(i=0; i<lemp->nsymbol; i++){
sp = lemp->symbols[i];
len = strlen(sp->name);
if( len>maxlen ) maxlen = len;
}
ncolumns = 76/(maxlen+5);
if( ncolumns<1 ) ncolumns = 1;
skip = (lemp->nsymbol + ncolumns - 1)/ncolumns;
for(i=0; i<skip; i++){
printf("//");
for(j=i; j<lemp->nsymbol; j+=skip){
sp = lemp->symbols[j];
assert( sp->index==j );
printf(" %3d %-*.*s",j,maxlen,maxlen,sp->name);
}
printf("\n");
}
for(rp=lemp->rule; rp; rp=rp->next){
printf("%s",rp->lhs->name);
/* if( rp->lhsalias ) printf("(%s)",rp->lhsalias); */
printf(" ::=");
for(i=0; i<rp->nrhs; i++){
printf(" %s",rp->rhs[i]->name);
/* if( rp->rhsalias[i] ) printf("(%s)",rp->rhsalias[i]); */
}
printf(".");
if( rp->precsym ) printf(" [%s]",rp->precsym->name);
/* if( rp->code ) printf("\n %s",rp->code); */
printf("\n");
}
}
void ConfigPrint(FILE *fp, struct config *cfp)
{
struct rule *rp;
int i;
rp = cfp->rp;
fprintf(fp,"%s ::=",rp->lhs->name);
for(i=0; i<=rp->nrhs; i++){
if( i==cfp->dot ) fprintf(fp," *");
if( i==rp->nrhs ) break;
fprintf(fp," %s",rp->rhs[i]->name);
}
}
/* #define TEST */
#ifdef TEST
/* Print a set */
PRIVATE void SetPrint(FILE *out, char *set, struct lemon *lemp)
{
int i;
char *spacer;
spacer = "";
fprintf(out,"%12s[","");
for(i=0; i<lemp->nterminal; i++){
if( SetFind(set,i) ){
fprintf(out,"%s%s",spacer,lemp->symbols[i]->name);
spacer = " ";
}
}
fprintf(out,"]\n");
}
/* Print a plink chain */
PRIVATE void PlinkPrint(FILE *out, struct plink *plp, char *tag)
{
while( plp ){
fprintf(out,"%12s%s (state %2d) ","",tag,plp->cfp->stp->index);
ConfigPrint(out,plp->cfp);
fprintf(out,"\n");
plp = plp->next;
}
}
#endif
/* Print an action to the given file descriptor. Return FALSE if
** nothing was actually printed.
*/
int PrintAction(struct action *ap, FILE *fp, int indent){
int result = 1;
switch( ap->type ){
case SHIFT:
fprintf(fp,"%*s shift %d",indent,ap->sp->name,ap->x.stp->index);
break;
case REDUCE:
fprintf(fp,"%*s reduce %d",indent,ap->sp->name,ap->x.rp->index);
break;
case ACCEPT:
fprintf(fp,"%*s accept",indent,ap->sp->name);
break;
case ERROR:
fprintf(fp,"%*s error",indent,ap->sp->name);
break;
case CONFLICT:
fprintf(fp,"%*s reduce %-3d ** Parsing conflict **",
indent,ap->sp->name,ap->x.rp->index);
break;
case SH_RESOLVED:
case RD_RESOLVED:
case NOT_USED:
result = 0;
break;
}
return result;
}
/* Generate the "y.output" log file */
void ReportOutput(struct lemon *lemp)
{
int i;
struct state *stp;
struct config *cfp;
struct action *ap;
FILE *fp;
fp = file_open(lemp,".out","w");
if( fp==0 ) return;
fprintf(fp," \b");
for(i=0; i<lemp->nstate; i++){
stp = lemp->sorted[i];
fprintf(fp,"State %d:\n",stp->index);
if( lemp->basisflag ) cfp=stp->bp;
else cfp=stp->cfp;
while( cfp ){
char buf[20];
if( cfp->dot==cfp->rp->nrhs ){
sprintf(buf,"(%d)",cfp->rp->index);
fprintf(fp," %5s ",buf);
}else{
fprintf(fp," ");
}
ConfigPrint(fp,cfp);
fprintf(fp,"\n");
#ifdef TEST
SetPrint(fp,cfp->fws,lemp);
PlinkPrint(fp,cfp->fplp,"To ");
PlinkPrint(fp,cfp->bplp,"From");
#endif
if( lemp->basisflag ) cfp=cfp->bp;
else cfp=cfp->next;
}
fprintf(fp,"\n");
for(ap=stp->ap; ap; ap=ap->next){
if( PrintAction(ap,fp,30) ) fprintf(fp,"\n");
}
fprintf(fp,"\n");
}
fclose(fp);
return;
}
/* Search for the file "name" which is in the same directory as
** the exacutable */
PRIVATE char *pathsearch(char *argv0, char *name, int modemask)
{
char *pathlist;
char *path,*cp;
char c;
#ifdef __WIN32__
cp = strrchr(argv0,'\\');
#else
cp = strrchr(argv0,'/');
#endif
if( cp ){
c = *cp;
*cp = 0;
path = (char *)malloc( strlen(argv0) + strlen(name) + 2 );
if( path ) sprintf(path,"%s/%s",argv0,name);
*cp = c;
}else{
extern char *getenv();
pathlist = getenv("PATH");
if( pathlist==0 ) pathlist = ".:/bin:/usr/bin";
path = (char *)malloc( strlen(pathlist)+strlen(name)+2 );
if( path!=0 ){
while( *pathlist ){
cp = strchr(pathlist,':');
if( cp==0 ) cp = &pathlist[strlen(pathlist)];
c = *cp;
*cp = 0;
sprintf(path,"%s/%s",pathlist,name);
*cp = c;
if( c==0 ) pathlist = "";
else pathlist = &cp[1];
if( access(path,modemask)==0 ) break;
}
}
}
return path;
}
/* Given an action, compute the integer value for that action
** which is to be put in the action table of the generated machine.
** Return negative if no action should be generated.
*/
PRIVATE int compute_action(struct lemon *lemp, struct action *ap)
{
int act;
switch( ap->type ){
case SHIFT: act = ap->x.stp->index; break;
case REDUCE: act = ap->x.rp->index + lemp->nstate; break;
case ERROR: act = lemp->nstate + lemp->nrule; break;
case ACCEPT: act = lemp->nstate + lemp->nrule + 1; break;
default: act = -1; break;
}
return act;
}
#define LINESIZE 1000
/* The next cluster of routines are for reading the template file
** and writing the results to the generated parser */
/* The first function transfers data from "in" to "out" until
** a line is seen which begins with "%%". The line number is
** tracked.
**
** if name!=0, then any word that begin with "Parse" is changed to
** begin with *name instead.
*/
PRIVATE void tplt_xfer(char *name, FILE *in, FILE *out, int *lineno)
{
int i, iStart;
char line[LINESIZE];
while( fgets(line,LINESIZE,in) && (line[0]!='%' || line[1]!='%') ){
(*lineno)++;
iStart = 0;
if( name ){
for(i=0; line[i]; i++){
if( line[i]=='P' && strncmp(&line[i],"Parse",5)==0
&& (i==0 || !safe_isalpha(line[i-1]))
){
if( i>iStart ) fprintf(out,"%.*s",i-iStart,&line[iStart]);
fprintf(out,"%s",name);
i += 4;
iStart = i+1;
}
}
}
fprintf(out,"%s",&line[iStart]);
}
}
/* The next function finds the template file and opens it, returning
** a pointer to the opened file. */
PRIVATE FILE *tplt_open(struct lemon *lemp)
{
static char templatename[] = "lempar.c";
char buf[1000];
FILE *in;
char *tpltname;
char *cp;
if (lemp->templatename) {
tpltname = lemp->templatename;
}
else {
cp = strrchr(lemp->filename,'.');
if( cp ){
sprintf(buf,"%.*s.lt",(int)(cp - lemp->filename),lemp->filename);
}else{
sprintf(buf,"%s.lt",lemp->filename);
}
if( access(buf,004)==0 ){
tpltname = buf;
}else{
tpltname = pathsearch(lemp->argv0,templatename,0);
}
}
if( tpltname==0 ){
fprintf(stderr,"Can't find the parser driver template file \"%s\".\n",
templatename);
lemp->errorcnt++;
return 0;
}
in = fopen(tpltname,"r");
if( in==0 ){
fprintf(stderr,"Can't open the template file \"%s\".\n",templatename);
lemp->errorcnt++;
return 0;
}
return in;
}
/* Print a string to the file and keep the linenumber up to date */
PRIVATE void tplt_print(FILE *out, struct lemon *lemp, char *str,
int strln, int *lineno)
{
if( str==0 ) return;
fprintf(out,"#line %d \"%s\"\n",strln,lemp->filename); (*lineno)++;
while( *str ){
if( *str=='\n' ) (*lineno)++;
putc(*str,out);
str++;
}
fprintf(out,"\n#line %d \"%s\"\n",*lineno+2,lemp->outname); (*lineno)+=2;
return;
}
/*
** The following routine emits code for the destructor for the
** symbol sp
*/
void emit_destructor_code(FILE *out, struct symbol *sp, struct lemon *lemp,
int *lineno)
{
char *cp;
int linecnt = 0;
if( sp->type==TERMINAL ){
cp = lemp->tokendest;
if( cp==0 ) return;
fprintf(out,"#line %d \"%s\"\n{",lemp->tokendestln,lemp->filename);
}else{
cp = sp->destructor;
if( cp==0 ) return;
fprintf(out,"#line %d \"%s\"\n{",sp->destructorln,lemp->filename);
}
for(; *cp; cp++){
if( *cp=='$' && cp[1]=='$' ){
fprintf(out,"(yypminor->yy%d)",sp->dtnum);
cp++;
continue;
}
if( *cp=='\n' ) linecnt++;
fputc(*cp,out);
}
(*lineno) += 3 + linecnt;
fprintf(out,"}\n#line %d \"%s\"\n",*lineno,lemp->outname);
return;
}
/*
** Return TRUE (non-zero) if the given symbol has a distructor.
*/
int has_destructor(struct symbol *sp, struct lemon *lemp)
{
int ret;
if( sp->type==TERMINAL ){
ret = lemp->tokendest!=0;
}else{
ret = sp->destructor!=0;
}
return ret;
}
/*
** Generate code which executes when the rule "rp" is reduced. Write
** the code to "out". Make sure lineno stays up-to-date.
*/
PRIVATE void emit_code(FILE *out, struct rule *rp, struct lemon *lemp,
int *lineno)
{
char *cp, *xp;
int linecnt = 0;
int i;
char lhsused = 0; /* True if the LHS element has been used */
char used[MAXRHS]; /* True for each RHS element which is used */
for(i=0; i<rp->nrhs; i++) used[i] = 0;
lhsused = 0;
/* Generate code to do the reduce action */
if( rp->code ){
fprintf(out,"#line %d \"%s\"\n{",rp->line,lemp->filename);
for(cp=rp->code; *cp; cp++){
if( safe_isalpha(*cp) && (cp==rp->code || !safe_isalnum(cp[-1])) ){
char saved;
for(xp= &cp[1]; safe_isalnum(*xp); xp++);
saved = *xp;
*xp = 0;
if( rp->lhsalias && strcmp(cp,rp->lhsalias)==0 ){
fprintf(out,"yygotominor.yy%d",rp->lhs->dtnum);
cp = xp;
lhsused = 1;
}else{
for(i=0; i<rp->nrhs; i++){
if( rp->rhsalias[i] && strcmp(cp,rp->rhsalias[i])==0 ){
fprintf(out,"yymsp[%d].minor.yy%d",i-rp->nrhs+1,rp->rhs[i]->dtnum);
cp = xp;
used[i] = 1;
break;
}
}
}
*xp = saved;
}
if( *cp=='\n' ) linecnt++;
fputc(*cp,out);
} /* End loop */
(*lineno) += 3 + linecnt;
fprintf(out,"}\n#line %d \"%s\"\n",*lineno,lemp->outname);
} /* End if( rp->code ) */
/* Check to make sure the LHS has been used */
if( rp->lhsalias && !lhsused ){
ErrorMsg(lemp->filename,rp->ruleline,
"Label \"%s\" for \"%s(%s)\" is never used.",
rp->lhsalias,rp->lhs->name,rp->lhsalias);
lemp->errorcnt++;
}
/* Generate destructor code for RHS symbols which are not used in the
** reduce code */
for(i=0; i<rp->nrhs; i++){
if( rp->rhsalias[i] && !used[i] ){
ErrorMsg(lemp->filename,rp->ruleline,
"Label $%s$ for \"%s(%s)\" is never used.",
rp->rhsalias[i],rp->rhs[i]->name,rp->rhsalias[i]);
lemp->errorcnt++;
}else if( rp->rhsalias[i]==0 ){
if( has_destructor(rp->rhs[i],lemp) ){
fprintf(out," yy_destructor(%d,&yymsp[%d].minor);\n",
rp->rhs[i]->index,i-rp->nrhs+1); (*lineno)++;
}else{
fprintf(out," /* No destructor defined for %s */\n",
rp->rhs[i]->name);
(*lineno)++;
}
}
}
return;
}
/*
** Print the definition of the union used for the parser's data stack.
** This union contains fields for every possible data type for tokens
** and nonterminals. In the process of computing and printing this
** union, also set the ".dtnum" field of every terminal and nonterminal
** symbol.
*/
void print_stack_union(
FILE *out, /* The output stream */
struct lemon *lemp, /* The main info structure for this parser */
int *plineno, /* Pointer to the line number */
int mhflag) /* True if generating makeheaders output */
{
int lineno = *plineno; /* The line number of the output */
char **types; /* A hash table of datatypes */
int arraysize; /* Size of the "types" array */
int maxdtlength; /* Maximum length of any ".datatype" field. */
char *stddt; /* Standardized name for a datatype */
int i,j; /* Loop counters */
int hash; /* For hashing the name of a type */
char *name; /* Name of the parser */
/* Allocate and initialize types[] and allocate stddt[] */
arraysize = lemp->nsymbol * 2;
types = (char**)malloc( arraysize * sizeof(char*) );
for(i=0; i<arraysize; i++) types[i] = 0;
maxdtlength = 0;
for(i=0; i<lemp->nsymbol; i++){
int len;
struct symbol *sp = lemp->symbols[i];
if( sp->datatype==0 ) continue;
len = strlen(sp->datatype);
if( len>maxdtlength ) maxdtlength = len;
}
stddt = (char*)malloc( maxdtlength*2 + 1 );
if( types==0 || stddt==0 ){
fprintf(stderr,"Out of memory.\n");
exit(1);
}
/* Build a hash table of datatypes. The ".dtnum" field of each symbol
** is filled in with the hash index plus 1. A ".dtnum" value of 0 is
** used for terminal symbols and for nonterminals which don't specify
** a datatype using the %type directive. */
for(i=0; i<lemp->nsymbol; i++){
struct symbol *sp = lemp->symbols[i];
char *cp;
if( sp==lemp->errsym ){
sp->dtnum = arraysize+1;
continue;
}
if( sp->type!=NONTERMINAL || sp->datatype==0 ){
sp->dtnum = 0;
continue;
}
cp = sp->datatype;
j = 0;
while( safe_isspace(*cp) ) cp++;
while( *cp ) stddt[j++] = *cp++;
while( j>0 && safe_isspace(stddt[j-1]) ) j--;
stddt[j] = 0;
hash = 0;
for(j=0; stddt[j]; j++){
hash = hash*53 + stddt[j];
}
if( hash<0 ) hash = -hash;
hash = hash%arraysize;
while( types[hash] ){
if( strcmp(types[hash],stddt)==0 ){
sp->dtnum = hash + 1;
break;
}
hash++;
if( hash>=arraysize ) hash = 0;
}
if( types[hash]==0 ){
sp->dtnum = hash + 1;
types[hash] = (char*)malloc( strlen(stddt)+1 );
if( types[hash]==0 ){
fprintf(stderr,"Out of memory.\n");
exit(1);
}
strcpy(types[hash],stddt);
}
}
/* Print out the definition of YYTOKENTYPE and YYMINORTYPE */
name = lemp->name ? lemp->name : "Parse";
lineno = *plineno;
if( mhflag ){ fprintf(out,"#if INTERFACE\n"); lineno++; }
fprintf(out,"#define %sTOKENTYPE %s\n",name,
lemp->tokentype?lemp->tokentype:"void*"); lineno++;
if( mhflag ){ fprintf(out,"#endif\n"); lineno++; }
fprintf(out,"typedef union {\n"); lineno++;
fprintf(out," %sTOKENTYPE yy0;\n",name); lineno++;
for(i=0; i<arraysize; i++){
if( types[i]==0 ) continue;
fprintf(out," %s yy%d;\n",types[i],i+1); lineno++;
free(types[i]);
}
fprintf(out," int yy%d;\n",lemp->errsym->dtnum); lineno++;
free(stddt);
free(types);
fprintf(out,"} YYMINORTYPE;\n"); lineno++;
*plineno = lineno;
}
/* Generate C source code for the parser */
void ReportTable(
struct lemon *lemp,
int mhflag) /* Output in makeheaders format if true */
{
FILE *out, *in;
char line[LINESIZE];
int lineno;
struct state *stp;
struct action *ap;
struct rule *rp;
int i;
int tablecnt;
char *name;
in = tplt_open(lemp);
if( in==0 ) return;
out = file_open(lemp,".c","w");
if( out==0 ){
fclose(in);
return;
}
lineno = 1;
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate the include code, if any */
tplt_print(out,lemp,lemp->include,lemp->includeln,&lineno);
if( mhflag ){
char *name = file_makename_using_basename(lemp, ".h");
fprintf(out,"#include \"%s\"\n", name); lineno++;
free(name);
}
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate #defines for all tokens */
if( mhflag ){
char *prefix;
fprintf(out,"#if INTERFACE\n"); lineno++;
if( lemp->tokenprefix ) prefix = lemp->tokenprefix;
else prefix = "";
for(i=1; i<lemp->nterminal; i++){
fprintf(out,"#define %s%-30s %2d\n",prefix,lemp->symbols[i]->name,i);
lineno++;
}
fprintf(out,"#endif\n"); lineno++;
}
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate the defines */
fprintf(out,"/* \001 */\n");
fprintf(out,"#define YYCODETYPE %s\n",
lemp->nsymbol>250?"int":"unsigned char"); lineno++;
fprintf(out,"#define YYNOCODE %d\n",lemp->nsymbol+1); lineno++;
fprintf(out,"#define YYACTIONTYPE %s\n",
lemp->nstate+lemp->nrule>250?"int":"unsigned char"); lineno++;
print_stack_union(out,lemp,&lineno,mhflag);
if( lemp->stacksize ){
if( atoi(lemp->stacksize)<=0 ){
ErrorMsg(lemp->filename,0,
"Illegal stack size: [%s]. The stack size should be an integer constant.",
lemp->stacksize);
lemp->errorcnt++;
lemp->stacksize = "100";
}
fprintf(out,"#define YYSTACKDEPTH %s\n",lemp->stacksize); lineno++;
}else{
fprintf(out,"#define YYSTACKDEPTH 100\n"); lineno++;
}
if( mhflag ){
fprintf(out,"#if INTERFACE\n"); lineno++;
}
name = lemp->name ? lemp->name : "Parse";
if( lemp->arg && lemp->arg[0] ){
int i;
i = strlen(lemp->arg);
while( i>=1 && safe_isspace(lemp->arg[i-1]) ) i--;
while( i>=1 && safe_isalnum(lemp->arg[i-1]) ) i--;
fprintf(out,"#define %sARGDECL ,%s\n",name,&lemp->arg[i]); lineno++;
fprintf(out,"#define %sXARGDECL %s;\n",name,lemp->arg); lineno++;
fprintf(out,"#define %sANSIARGDECL ,%s\n",name,lemp->arg); lineno++;
}else{
fprintf(out,"#define %sARGDECL\n",name); lineno++;
fprintf(out,"#define %sXARGDECL\n",name); lineno++;
fprintf(out,"#define %sANSIARGDECL\n",name); lineno++;
}
if( mhflag ){
fprintf(out,"#endif\n"); lineno++;
}
fprintf(out,"#define YYNSTATE %d\n",lemp->nstate); lineno++;
fprintf(out,"#define YYNRULE %d\n",lemp->nrule); lineno++;
fprintf(out,"#define YYERRORSYMBOL %d\n",lemp->errsym->index); lineno++;
fprintf(out,"#define YYERRSYMDT yy%d\n",lemp->errsym->dtnum); lineno++;
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate the action table.
**
** Each entry in the action table is an element of the following
** structure:
** struct yyActionEntry {
** YYCODETYPE lookahead;
** YYACTIONTYPE action;
** struct yyActionEntry *next;
** }
**
** The entries are grouped into hash tables, one hash table for each
** parser state. The hash table has a size which is the smallest
** power of two needed to hold all entries.
*/
tablecnt = 0;
/* Loop over parser states */
for(i=0; i<lemp->nstate; i++){
int tablesize; /* size of the hash table */
int j,k; /* Loop counter */
int collide[2048]; /* The collision chain for the table */
struct action *table[2048]; /* Build the hash table here */
/* Find the number of actions and initialize the hash table */
stp = lemp->sorted[i];
stp->tabstart = tablecnt;
stp->naction = 0;
for(ap=stp->ap; ap; ap=ap->next){
if( ap->sp->index!=lemp->nsymbol && compute_action(lemp,ap)>=0 ){
stp->naction++;
}
}
tablesize = 1;
while( tablesize<stp->naction ) tablesize += tablesize;
assert( tablesize<= sizeof(table)/sizeof(table[0]) );
for(j=0; j<tablesize; j++){
table[j] = 0;
collide[j] = -1;
}
/* Hash the actions into the hash table */
stp->tabdfltact = lemp->nstate + lemp->nrule;
for(ap=stp->ap; ap; ap=ap->next){
int action = compute_action(lemp,ap);
int h;
if( ap->sp->index==lemp->nsymbol ){
stp->tabdfltact = action;
}else if( action>=0 ){
h = ap->sp->index & (tablesize-1);
ap->collide = table[h];
table[h] = ap;
}
}
/* Resolve collisions */
for(j=k=0; j<tablesize; j++){
if( table[j] && table[j]->collide ){
while( table[k] ) k++;
table[k] = table[j]->collide;
collide[j] = k;
table[j]->collide = 0;
if( k<j ) j = k-1;
}
}
/* Print the hash table */
fprintf(out,"/* State %d */\n",stp->index); lineno++;
for(j=0; j<tablesize; j++){
if( table[j]==0 ){
fprintf(out,
" {YYNOCODE,0,0}, /* Unused */\n");
}else{
fprintf(out," {%4d,%4d, ",
table[j]->sp->index,
compute_action(lemp,table[j]));
if( collide[j]>=0 ){
fprintf(out,"&yyActionTable[%4d] }, /* ",
collide[j] + tablecnt);
}else{
fprintf(out,"0 }, /* ");
}
PrintAction(table[j],out,22);
fprintf(out," */\n");
}
lineno++;
}
/* Update the table count */
tablecnt += tablesize;
}
tplt_xfer(lemp->name,in,out,&lineno);
lemp->tablesize = tablecnt;
/* Generate the state table
**
** Each entry is an element of the following structure:
** struct yyStateEntry {
** struct yyActionEntry *hashtbl;
** int mask;
** YYACTIONTYPE actionDefault;
** }
*/
for(i=0; i<lemp->nstate; i++){
int tablesize;
stp = lemp->sorted[i];
tablesize = 1;
while( tablesize<stp->naction ) tablesize += tablesize;
fprintf(out," { &yyActionTable[%d], %d, %d},\n",
stp->tabstart,
tablesize - 1,
stp->tabdfltact); lineno++;
}
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate a table containing the symbolic name of every symbol */
for(i=0; i<lemp->nsymbol; i++){
sprintf(line,"\"%s\",",lemp->symbols[i]->name);
fprintf(out," %-15s",line);
if( (i&3)==3 ){ fprintf(out,"\n"); lineno++; }
}
if( (i&3)!=0 ){ fprintf(out,"\n"); lineno++; }
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate code which executes every time a symbol is popped from
** the stack while processing errors or while destroying the parser.
** (In other words, generate the %destructor actions) */
if( lemp->tokendest ){
for(i=0; i<lemp->nsymbol; i++){
struct symbol *sp = lemp->symbols[i];
if( sp==0 || sp->type!=TERMINAL ) continue;
fprintf(out," case %d:\n",sp->index); lineno++;
}
for(i=0; i<lemp->nsymbol && lemp->symbols[i]->type!=TERMINAL; i++);
if( i<lemp->nsymbol ){
emit_destructor_code(out,lemp->symbols[i],lemp,&lineno);
fprintf(out," break;\n"); lineno++;
}
}
for(i=0; i<lemp->nsymbol; i++){
struct symbol *sp = lemp->symbols[i];
if( sp==0 || sp->type==TERMINAL || sp->destructor==0 ) continue;
fprintf(out," case %d:\n",sp->index); lineno++;
emit_destructor_code(out,lemp->symbols[i],lemp,&lineno);
fprintf(out," break;\n"); lineno++;
}
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate code which executes whenever the parser stack overflows */
tplt_print(out,lemp,lemp->overflow,lemp->overflowln,&lineno);
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate the table of rule information
**
** Note: This code depends on the fact that rules are number
** sequentually beginning with 0.
*/
for(rp=lemp->rule; rp; rp=rp->next){
fprintf(out," { %d, %d },\n",rp->lhs->index,rp->nrhs); lineno++;
}
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate code which execution during each REDUCE action */
for(rp=lemp->rule; rp; rp=rp->next){
fprintf(out," case %d:\n",rp->index); lineno++;
fprintf(out," YYTRACE(\"%s ::=",rp->lhs->name);
for(i=0; i<rp->nrhs; i++) fprintf(out," %s",rp->rhs[i]->name);
fprintf(out,"\")\n"); lineno++;
emit_code(out,rp,lemp,&lineno);
fprintf(out," break;\n"); lineno++;
}
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate code which executes if a parse fails */
tplt_print(out,lemp,lemp->failure,lemp->failureln,&lineno);
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate code which executes when a syntax error occurs */
tplt_print(out,lemp,lemp->error,lemp->errorln,&lineno);
tplt_xfer(lemp->name,in,out,&lineno);
/* Generate code which executes when the parser accepts its input */
tplt_print(out,lemp,lemp->accept,lemp->acceptln,&lineno);
tplt_xfer(lemp->name,in,out,&lineno);
/* Append any addition code the user desires */
tplt_print(out,lemp,lemp->extracode,lemp->extracodeln,&lineno);
fclose(in);
fclose(out);
return;
}
/* Generate a header file for the parser */
void ReportHeader(struct lemon *lemp)
{
FILE *out, *in;
char *prefix;
char line[LINESIZE];
char pattern[LINESIZE];
int i;
if( lemp->tokenprefix ) prefix = lemp->tokenprefix;
else prefix = "";
in = file_open(lemp,".h","r");
if( in ){
for(i=1; i<lemp->nterminal && fgets(line,LINESIZE,in); i++){
sprintf(pattern,"#define %s%-30s %2d\n",prefix,lemp->symbols[i]->name,i);
if( strcmp(line,pattern) ) break;
}
fclose(in);
if( i==lemp->nterminal ){
/* No change in the file. Don't rewrite it. */
return;
}
}
out = file_open(lemp,".h","w");
if( out ){
for(i=1; i<lemp->nterminal; i++){
fprintf(out,"#define %s%-30s %2d\n",prefix,lemp->symbols[i]->name,i);
}
fclose(out);
}
return;
}
/* Reduce the size of the action tables, if possible, by making use
** of defaults.
**
** In this version, if all REDUCE actions use the same rule, make
** them the default. Only default them if there are more than one.
*/
void CompressTables(struct lemon *lemp)
{
struct state *stp;
struct action *ap;
struct rule *rp;
int i;
int cnt;
for(i=0; i<lemp->nstate; i++){
stp = lemp->sorted[i];
/* Find the first REDUCE action */
for(ap=stp->ap; ap && ap->type!=REDUCE; ap=ap->next);
if( ap==0 ) continue;
/* Remember the rule used */
rp = ap->x.rp;
/* See if all other REDUCE acitons use the same rule */
cnt = 1;
for(ap=ap->next; ap; ap=ap->next){
if( ap->type==REDUCE ){
if( ap->x.rp!=rp ) break;
cnt++;
}
}
if( ap || cnt==1 ) continue;
/* Combine all REDUCE actions into a single default */
for(ap=stp->ap; ap && ap->type!=REDUCE; ap=ap->next);
assert( ap );
ap->sp = Symbol_new("{default}");
for(ap=ap->next; ap; ap=ap->next){
if( ap->type==REDUCE ) ap->type = NOT_USED;
}
stp->ap = Action_sort(stp->ap);
}
}
/***************** From the file "set.c" ************************************/
/*
** Set manipulation routines for the LEMON parser generator.
*/
static int size = 0;
/* Set the set size */
void SetSize(int n)
{
size = n+1;
}
/* Allocate a new set */
char *SetNew(void){
char *s;
int i;
s = (char*)malloc( size );
if( s==0 ){
extern void memory_error();
memory_error();
}
for(i=0; i<size; i++) s[i] = 0;
return s;
}
/* Deallocate a set */
void SetFree(char *s)
{
free(s);
}
/* Add a new element to the set. Return TRUE if the element was added
** and FALSE if it was already there. */
int SetAdd(char *s, int e)
{
int rv;
rv = s[e];
s[e] = 1;
return !rv;
}
/* Add every element of s2 to s1. Return TRUE if s1 changes. */
int SetUnion(char *s1, char *s2)
{
int i, progress;
progress = 0;
for(i=0; i<size; i++){
if( s2[i]==0 ) continue;
if( s1[i]==0 ){
progress = 1;
s1[i] = 1;
}
}
return progress;
}
/********************** From the file "table.c" ****************************/
/*
** All code in this file has been automatically generated
** from a specification in the file
** "table.q"
** by the associative array code building program "aagen".
** Do not edit this file! Instead, edit the specification
** file, then rerun aagen.
*/
/*
** Code for processing tables in the LEMON parser generator.
*/
PRIVATE int strhash(char *x)
{
int h = 0;
while( *x) h = h*13 + *(x++);
return h;
}
/* Works like strdup, sort of. Save a string in malloced memory, but
** keep strings in a table so that the same string is not in more
** than one place.
*/
char *Strsafe(char *y)
{
char *z;
z = Strsafe_find(y);
if( z==0 && (z=malloc( strlen(y)+1 ))!=0 ){
strcpy(z,y);
Strsafe_insert(z);
}
MemoryCheck(z);
return z;
}
/* There is one instance of the following structure for each
** associative array of type "x1".
*/
struct s_x1 {
int size; /* The number of available slots. */
/* Must be a power of 2 greater than or */
/* equal to 1 */
int count; /* Number of currently slots filled */
struct s_x1node *tbl; /* The data stored here */
struct s_x1node **ht; /* Hash table for lookups */
};
/* There is one instance of this structure for every data element
** in an associative array of type "x1".
*/
typedef struct s_x1node {
char *data; /* The data */
struct s_x1node *next; /* Next entry with the same hash */
struct s_x1node **from; /* Previous link */
} x1node;
/* There is only one instance of the array, which is the following */
static struct s_x1 *x1a;
/* Allocate a new associative array */
void Strsafe_init(void){
if( x1a ) return;
x1a = (struct s_x1*)malloc( sizeof(struct s_x1) );
if( x1a ){
x1a->size = 1024;
x1a->count = 0;
x1a->tbl = (x1node*)malloc(
(sizeof(x1node) + sizeof(x1node*))*1024 );
if( x1a->tbl==0 ){
free(x1a);
x1a = 0;
}else{
int i;
x1a->ht = (x1node**)&(x1a->tbl[1024]);
for(i=0; i<1024; i++) x1a->ht[i] = 0;
}
}
}
/* Insert a new record into the array. Return TRUE if successful.
** Prior data with the same key is NOT overwritten */
int Strsafe_insert(char *data)
{
x1node *np;
int h;
int ph;
if( x1a==0 ) return 0;
ph = strhash(data);
h = ph & (x1a->size-1);
np = x1a->ht[h];
while( np ){
if( strcmp(np->data,data)==0 ){
/* An existing entry with the same key is found. */
/* Fail because overwrite is not allows. */
return 0;
}
np = np->next;
}
if( x1a->count>=x1a->size ){
/* Need to make the hash table bigger */
int i,size;
struct s_x1 array;
array.size = size = x1a->size*2;
array.count = x1a->count;
array.tbl = (x1node*)malloc(
(sizeof(x1node) + sizeof(x1node*))*size );
if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
array.ht = (x1node**)&(array.tbl[size]);
for(i=0; i<size; i++) array.ht[i] = 0;
for(i=0; i<x1a->count; i++){
x1node *oldnp, *newnp;
oldnp = &(x1a->tbl[i]);
h = strhash(oldnp->data) & (size-1);
newnp = &(array.tbl[i]);
if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
newnp->next = array.ht[h];
newnp->data = oldnp->data;
newnp->from = &(array.ht[h]);
array.ht[h] = newnp;
}
free(x1a->tbl);
*x1a = array;
}
/* Insert the new data */
h = ph & (x1a->size-1);
np = &(x1a->tbl[x1a->count++]);
np->data = data;
if( x1a->ht[h] ) x1a->ht[h]->from = &(np->next);
np->next = x1a->ht[h];
x1a->ht[h] = np;
np->from = &(x1a->ht[h]);
return 1;
}
/* Return a pointer to data assigned to the given key. Return NULL
** if no such key. */
char *Strsafe_find(char *key)
{
int h;
x1node *np;
if( x1a==0 ) return 0;
h = strhash(key) & (x1a->size-1);
np = x1a->ht[h];
while( np ){
if( strcmp(np->data,key)==0 ) break;
np = np->next;
}
return np ? np->data : 0;
}
/* Return a pointer to the (terminal or nonterminal) symbol "x".
** Create a new symbol if this is the first time "x" has been seen.
*/
struct symbol *Symbol_new(char *x)
{
struct symbol *sp;
sp = Symbol_find(x);
if( sp==0 ){
sp = (struct symbol *)malloc( sizeof(struct symbol) );
MemoryCheck(sp);
sp->name = Strsafe(x);
sp->type = safe_isupper(*x) ? TERMINAL : NONTERMINAL;
sp->rule = 0;
sp->prec = -1;
sp->assoc = UNK;
sp->firstset = 0;
sp->lambda = FALSE;
sp->destructor = 0;
sp->datatype = 0;
Symbol_insert(sp,sp->name);
}
return sp;
}
/* Compare two symbols */
int Symbolcmpp(struct symbol **a, struct symbol **b)
{
return strcmp((**a).name,(**b).name);
}
/* There is one instance of the following structure for each
** associative array of type "x2".
*/
struct s_x2 {
int size; /* The number of available slots. */
/* Must be a power of 2 greater than or */
/* equal to 1 */
int count; /* Number of currently slots filled */
struct s_x2node *tbl; /* The data stored here */
struct s_x2node **ht; /* Hash table for lookups */
};
/* There is one instance of this structure for every data element
** in an associative array of type "x2".
*/
typedef struct s_x2node {
struct symbol *data; /* The data */
char *key; /* The key */
struct s_x2node *next; /* Next entry with the same hash */
struct s_x2node **from; /* Previous link */
} x2node;
/* There is only one instance of the array, which is the following */
static struct s_x2 *x2a;
/* Allocate a new associative array */
void Symbol_init(void){
if( x2a ) return;
x2a = (struct s_x2*)malloc( sizeof(struct s_x2) );
if( x2a ){
x2a->size = 128;
x2a->count = 0;
x2a->tbl = (x2node*)malloc(
(sizeof(x2node) + sizeof(x2node*))*128 );
if( x2a->tbl==0 ){
free(x2a);
x2a = 0;
}else{
int i;
x2a->ht = (x2node**)&(x2a->tbl[128]);
for(i=0; i<128; i++) x2a->ht[i] = 0;
}
}
}
/* Insert a new record into the array. Return TRUE if successful.
** Prior data with the same key is NOT overwritten */
int Symbol_insert(struct symbol *data, char *key)
{
x2node *np;
int h;
int ph;
if( x2a==0 ) return 0;
ph = strhash(key);
h = ph & (x2a->size-1);
np = x2a->ht[h];
while( np ){
if( strcmp(np->key,key)==0 ){
/* An existing entry with the same key is found. */
/* Fail because overwrite is not allows. */
return 0;
}
np = np->next;
}
if( x2a->count>=x2a->size ){
/* Need to make the hash table bigger */
int i,size;
struct s_x2 array;
array.size = size = x2a->size*2;
array.count = x2a->count;
array.tbl = (x2node*)malloc(
(sizeof(x2node) + sizeof(x2node*))*size );
if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
array.ht = (x2node**)&(array.tbl[size]);
for(i=0; i<size; i++) array.ht[i] = 0;
for(i=0; i<x2a->count; i++){
x2node *oldnp, *newnp;
oldnp = &(x2a->tbl[i]);
h = strhash(oldnp->key) & (size-1);
newnp = &(array.tbl[i]);
if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
newnp->next = array.ht[h];
newnp->key = oldnp->key;
newnp->data = oldnp->data;
newnp->from = &(array.ht[h]);
array.ht[h] = newnp;
}
free(x2a->tbl);
*x2a = array;
}
/* Insert the new data */
h = ph & (x2a->size-1);
np = &(x2a->tbl[x2a->count++]);
np->key = key;
np->data = data;
if( x2a->ht[h] ) x2a->ht[h]->from = &(np->next);
np->next = x2a->ht[h];
x2a->ht[h] = np;
np->from = &(x2a->ht[h]);
return 1;
}
/* Return a pointer to data assigned to the given key. Return NULL
** if no such key. */
struct symbol *Symbol_find(char *key)
{
int h;
x2node *np;
if( x2a==0 ) return 0;
h = strhash(key) & (x2a->size-1);
np = x2a->ht[h];
while( np ){
if( strcmp(np->key,key)==0 ) break;
np = np->next;
}
return np ? np->data : 0;
}
/* Return the n-th data. Return NULL if n is out of range. */
struct symbol *Symbol_Nth(int n)
{
struct symbol *data;
if( x2a && n>0 && n<=x2a->count ){
data = x2a->tbl[n-1].data;
}else{
data = 0;
}
return data;
}
/* Return the size of the array */
int Symbol_count(void)
{
return x2a ? x2a->count : 0;
}
/* Return an array of pointers to all data in the table.
** The array is obtained from malloc. Return NULL if memory allocation
** problems, or if the array is empty. */
struct symbol **Symbol_arrayof(void)
{
struct symbol **array;
int i,size;
if( x2a==0 ) return 0;
size = x2a->count;
array = (struct symbol **)malloc( sizeof(struct symbol *)*size );
if( array ){
for(i=0; i<size; i++) array[i] = x2a->tbl[i].data;
}
return array;
}
/* Compare two configurations */
int Configcmp(void *a_arg, void *b_arg)
{
struct config *a = a_arg, *b = b_arg;
int x;
x = a->rp->index - b->rp->index;
if( x==0 ) x = a->dot - b->dot;
return x;
}
/* Compare two states */
PRIVATE int statecmp(struct config *a, struct config *b)
{
int rc;
for(rc=0; rc==0 && a && b; a=a->bp, b=b->bp){
rc = a->rp->index - b->rp->index;
if( rc==0 ) rc = a->dot - b->dot;
}
if( rc==0 ){
if( a ) rc = 1;
if( b ) rc = -1;
}
return rc;
}
/* Hash a state */
PRIVATE int statehash(struct config *a)
{
int h=0;
while( a ){
h = h*571 + a->rp->index*37 + a->dot;
a = a->bp;
}
return h;
}
/* Allocate a new state structure */
struct state *State_new(void)
{
struct state *new;
new = (struct state *)malloc( sizeof(struct state) );
MemoryCheck(new);
return new;
}
/* There is one instance of the following structure for each
** associative array of type "x3".
*/
struct s_x3 {
int size; /* The number of available slots. */
/* Must be a power of 2 greater than or */
/* equal to 1 */
int count; /* Number of currently slots filled */
struct s_x3node *tbl; /* The data stored here */
struct s_x3node **ht; /* Hash table for lookups */
};
/* There is one instance of this structure for every data element
** in an associative array of type "x3".
*/
typedef struct s_x3node {
struct state *data; /* The data */
struct config *key; /* The key */
struct s_x3node *next; /* Next entry with the same hash */
struct s_x3node **from; /* Previous link */
} x3node;
/* There is only one instance of the array, which is the following */
static struct s_x3 *x3a;
/* Allocate a new associative array */
void State_init(void){
if( x3a ) return;
x3a = (struct s_x3*)malloc( sizeof(struct s_x3) );
if( x3a ){
x3a->size = 128;
x3a->count = 0;
x3a->tbl = (x3node*)malloc(
(sizeof(x3node) + sizeof(x3node*))*128 );
if( x3a->tbl==0 ){
free(x3a);
x3a = 0;
}else{
int i;
x3a->ht = (x3node**)&(x3a->tbl[128]);
for(i=0; i<128; i++) x3a->ht[i] = 0;
}
}
}
/* Insert a new record into the array. Return TRUE if successful.
** Prior data with the same key is NOT overwritten */
int State_insert(struct state *data, struct config *key)
{
x3node *np;
int h;
int ph;
if( x3a==0 ) return 0;
ph = statehash(key);
h = ph & (x3a->size-1);
np = x3a->ht[h];
while( np ){
if( statecmp(np->key,key)==0 ){
/* An existing entry with the same key is found. */
/* Fail because overwrite is not allows. */
return 0;
}
np = np->next;
}
if( x3a->count>=x3a->size ){
/* Need to make the hash table bigger */
int i,size;
struct s_x3 array;
array.size = size = x3a->size*2;
array.count = x3a->count;
array.tbl = (x3node*)malloc(
(sizeof(x3node) + sizeof(x3node*))*size );
if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
array.ht = (x3node**)&(array.tbl[size]);
for(i=0; i<size; i++) array.ht[i] = 0;
for(i=0; i<x3a->count; i++){
x3node *oldnp, *newnp;
oldnp = &(x3a->tbl[i]);
h = statehash(oldnp->key) & (size-1);
newnp = &(array.tbl[i]);
if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
newnp->next = array.ht[h];
newnp->key = oldnp->key;
newnp->data = oldnp->data;
newnp->from = &(array.ht[h]);
array.ht[h] = newnp;
}
free(x3a->tbl);
*x3a = array;
}
/* Insert the new data */
h = ph & (x3a->size-1);
np = &(x3a->tbl[x3a->count++]);
np->key = key;
np->data = data;
if( x3a->ht[h] ) x3a->ht[h]->from = &(np->next);
np->next = x3a->ht[h];
x3a->ht[h] = np;
np->from = &(x3a->ht[h]);
return 1;
}
/* Return a pointer to data assigned to the given key. Return NULL
** if no such key. */
struct state *State_find(struct config *key)
{
int h;
x3node *np;
if( x3a==0 ) return 0;
h = statehash(key) & (x3a->size-1);
np = x3a->ht[h];
while( np ){
if( statecmp(np->key,key)==0 ) break;
np = np->next;
}
return np ? np->data : 0;
}
/* Return an array of pointers to all data in the table.
** The array is obtained from malloc. Return NULL if memory allocation
** problems, or if the array is empty. */
struct state **State_arrayof(void)
{
struct state **array;
int i,size;
if( x3a==0 ) return 0;
size = x3a->count;
array = (struct state **)malloc( sizeof(struct state *)*size );
if( array ){
for(i=0; i<size; i++) array[i] = x3a->tbl[i].data;
}
return array;
}
/* Hash a configuration */
PRIVATE int confighash(struct config *a)
{
int h=0;
h = h*571 + a->rp->index*37 + a->dot;
return h;
}
/* There is one instance of the following structure for each
** associative array of type "x4".
*/
struct s_x4 {
int size; /* The number of available slots. */
/* Must be a power of 2 greater than or */
/* equal to 1 */
int count; /* Number of currently slots filled */
struct s_x4node *tbl; /* The data stored here */
struct s_x4node **ht; /* Hash table for lookups */
};
/* There is one instance of this structure for every data element
** in an associative array of type "x4".
*/
typedef struct s_x4node {
struct config *data; /* The data */
struct s_x4node *next; /* Next entry with the same hash */
struct s_x4node **from; /* Previous link */
} x4node;
/* There is only one instance of the array, which is the following */
static struct s_x4 *x4a;
/* Allocate a new associative array */
void Configtable_init(void){
if( x4a ) return;
x4a = (struct s_x4*)malloc( sizeof(struct s_x4) );
if( x4a ){
x4a->size = 64;
x4a->count = 0;
x4a->tbl = (x4node*)malloc(
(sizeof(x4node) + sizeof(x4node*))*64 );
if( x4a->tbl==0 ){
free(x4a);
x4a = 0;
}else{
int i;
x4a->ht = (x4node**)&(x4a->tbl[64]);
for(i=0; i<64; i++) x4a->ht[i] = 0;
}
}
}
/* Insert a new record into the array. Return TRUE if successful.
** Prior data with the same key is NOT overwritten */
int Configtable_insert(struct config *data)
{
x4node *np;
int h;
int ph;
if( x4a==0 ) return 0;
ph = confighash(data);
h = ph & (x4a->size-1);
np = x4a->ht[h];
while( np ){
if( Configcmp(np->data,data)==0 ){
/* An existing entry with the same key is found. */
/* Fail because overwrite is not allows. */
return 0;
}
np = np->next;
}
if( x4a->count>=x4a->size ){
/* Need to make the hash table bigger */
int i,size;
struct s_x4 array;
array.size = size = x4a->size*2;
array.count = x4a->count;
array.tbl = (x4node*)malloc(
(sizeof(x4node) + sizeof(x4node*))*size );
if( array.tbl==0 ) return 0; /* Fail due to malloc failure */
array.ht = (x4node**)&(array.tbl[size]);
for(i=0; i<size; i++) array.ht[i] = 0;
for(i=0; i<x4a->count; i++){
x4node *oldnp, *newnp;
oldnp = &(x4a->tbl[i]);
h = confighash(oldnp->data) & (size-1);
newnp = &(array.tbl[i]);
if( array.ht[h] ) array.ht[h]->from = &(newnp->next);
newnp->next = array.ht[h];
newnp->data = oldnp->data;
newnp->from = &(array.ht[h]);
array.ht[h] = newnp;
}
free(x4a->tbl);
*x4a = array;
}
/* Insert the new data */
h = ph & (x4a->size-1);
np = &(x4a->tbl[x4a->count++]);
np->data = data;
if( x4a->ht[h] ) x4a->ht[h]->from = &(np->next);
np->next = x4a->ht[h];
x4a->ht[h] = np;
np->from = &(x4a->ht[h]);
return 1;
}
/* Return a pointer to data assigned to the given key. Return NULL
** if no such key. */
struct config *Configtable_find(struct config *key)
{
int h;
x4node *np;
if( x4a==0 ) return 0;
h = confighash(key) & (x4a->size-1);
np = x4a->ht[h];
while( np ){
if( Configcmp(np->data,key)==0 ) break;
np = np->next;
}
return np ? np->data : 0;
}
/* Remove all data from the table. Pass each data to the function "f"
** as it is removed. ("f" may be null to avoid this step.) */
void Configtable_clear(int(*f)(struct config *))
{
int i;
if( x4a==0 || x4a->count==0 ) return;
if( f ) for(i=0; i<x4a->count; i++) (*f)(x4a->tbl[i].data);
for(i=0; i<x4a->size; i++) x4a->ht[i] = 0;
x4a->count = 0;
return;
}