lemon.c

ethereal公司开发的aodv路由协议代码

  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*),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)(const void *, const 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)(const void *, const 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: