parse.c

来自「eCos操作系统源码」· C语言 代码 · 共 2,108 行 · 第 1/5 页

	 */

    for ( mp = module_head ; mp ; mp = mp->next )
         if ( mp->modid == modid )
             break;
    if ( mp )
         for ( i=0, mip=mp->imports ; i < mp->no_imports ; ++i, ++mip ) {
             if ( !label_compare( mip->label, descriptor )) {
				/* Found it - so amend the module ID */
                  modid = mip->modid;
                  break;
             }
         }


    for(i=0, tcp=tclist; i < MAXTC; i++, tcp++){
      if (tcp->type == 0)
          break;
      if (!label_compare(descriptor, tcp->descriptor) &&
		((modid == tcp->modid) || (modid == -1))){
          return i;
      }
    }
    return -1;
}

/* translate integer tc_index to string identifier from tclist
 *
 * Returns pointer to string in table (should not be modified) or NULL
 */
const char *
get_tc_descriptor(int tc_index)
{
  if (tc_index < 0 || tc_index >= MAXTC) return NULL;
  return (tclist[tc_index].descriptor);
}


/*
 * Parses an enumeration list of the form:
 *        { label(value) label(value) ... }
 * The initial { has already been parsed.
 * Returns NULL on error.
 */

static struct enum_list *
parse_enumlist(FILE *fp, struct enum_list **retp)
{
    register int type;
    char token [MAXTOKEN];
    struct enum_list *ep = NULL, **epp = &ep;

    free_enums(retp);

    while((type = get_token(fp, token, MAXTOKEN)) != ENDOFFILE){
        if (type == RIGHTBRACKET)
            break;
        if (type == LABEL){
            /* this is an enumerated label */
            *epp = (struct enum_list *) calloc(1, sizeof(struct enum_list));
            if (*epp == NULL) return(NULL);
            /* a reasonable approximation for the length */
            (*epp)->label = strdup(token);
            type = get_token(fp, token, MAXTOKEN);
            if (type != LEFTPAREN) {
                print_error("Expected \"(\"", token, type);
                return NULL;
            }
            type = get_token(fp, token, MAXTOKEN);
            if (type != NUMBER) {
                print_error("Expected integer", token, type);
                return NULL;
            }
            (*epp)->value = atoi(token);
            type = get_token(fp, token, MAXTOKEN);
            if (type != RIGHTPAREN) {
                print_error("Expected \")\"", token, type);
                return NULL;
            }
            epp = &(*epp)->next;
        }
    }
    if (type == ENDOFFILE){
        print_error("Expected \"}\"", token, type);
        return NULL;
    }
    *retp = ep;
    return ep;
}

static struct range_list *parse_ranges(FILE *fp, struct range_list **retp)
{   int low, high;
    char nexttoken[MAXTOKEN];
    int nexttype;
    struct range_list *rp = NULL, **rpp = &rp;
    int size = 0, taken = 1;

    free_ranges(retp);

    nexttype = get_token(fp, nexttoken, MAXTOKEN);
    if (nexttype == SIZE) {
	size = 1;
	taken = 0;
	nexttype = get_token(fp, nexttoken, MAXTOKEN);
	if (nexttype != LEFTPAREN)
	    print_error("Expected \"(\" after SIZE", nexttoken, nexttype);
    }

    do {
	if (!taken) nexttype = get_token(fp, nexttoken, MAXTOKEN);
	else taken = 0;
	high = low = atol(nexttoken);
	nexttype = get_token(fp, nexttoken, MAXTOKEN);
	if (nexttype == RANGE) {
	    nexttype = get_token(fp, nexttoken, MAXTOKEN);
	    high = atol(nexttoken);
	    nexttype = get_token(fp, nexttoken, MAXTOKEN);
	}
	*rpp = (struct range_list *)calloc (1, sizeof(struct range_list));
	if (*rpp == NULL) break;
	(*rpp)->low = low;
	(*rpp)->high = high;
	rpp = &(*rpp)->next;

    } while (nexttype == BAR);
    if (size) {
	if (nexttype != RIGHTPAREN)
	    print_error ("Expected \")\" after SIZE", nexttoken, nexttype);
	nexttype = get_token(fp, nexttoken, nexttype);
    }
    if (nexttype != RIGHTPAREN)
	print_error ("Expected \")\"", nexttoken, nexttype);

    *retp = rp;
    return rp;
}

/*
 * Parses an asn type.  Structures are ignored by this parser.
 * Returns NULL on error.
 */
static struct node *
parse_asntype(FILE *fp,
	      char *name,
	      int *ntype,
	      char *ntoken)
{
    int type, i;
    char token[MAXTOKEN];
    char quoted_string_buffer[MAXQUOTESTR];
    char *hint = NULL;
    struct tc *tcp;
    int level;

    type = get_token(fp, token, MAXTOKEN);
    if (type == SEQUENCE){
        level = 0;
        while((type = get_token(fp, token, MAXTOKEN)) != ENDOFFILE){
            if (type == LEFTBRACKET){
                level++;
            }
            else if (type == RIGHTBRACKET && --level == 0){
                *ntype = get_token(fp, ntoken, MAXTOKEN);
                return NULL;
            }
        }
        print_error("Expected \"}\"", token, type);
        return NULL;
    } else if (type == LEFTBRACKET) {
        struct node *np;
        int ch_next = '{';
        ungetc(ch_next, fp);
        np = parse_objectid (fp, name);
        if (np != NULL) {
            *ntype = get_token(fp, ntoken, MAXTOKEN);
            return np;
        }
        return NULL;
    } else {
        if (type == CONVENTION) {
            while (type != SYNTAX && type != ENDOFFILE) {
                if (type == DISPLAYHINT) {
                    type = get_token(fp, token, MAXTOKEN);
                    if (type != QUOTESTRING) print_error("DISPLAY-HINT must be string", token, type);
                    else hint = strdup (token);
                }
                else
		    type = get_token(fp, quoted_string_buffer, MAXQUOTESTR);
            }
            type = get_token(fp, token, MAXTOKEN);
        }

        if (type == LABEL)
        {
            type = get_tc(token, current_module, NULL, NULL, NULL, NULL);
        }

        /* textual convention */
        for(i = 0; i < MAXTC; i++){
            if (tclist[i].type == 0)
                break;
        }

        if (i == MAXTC){
            print_error("Too many textual conventions", token, type);
            SNMP_FREE(hint);
            return NULL;
        }
        if (!(type & SYNTAX_MASK)){
            print_error("Textual convention doesn't map to real type", token,
                        type);
            SNMP_FREE(hint);
            return NULL;
        }
        tcp = &tclist[i];
        tcp->modid = current_module;
        tcp->descriptor = strdup(name);
        tcp->hint = hint;
        tcp->type = type;
        *ntype = get_token(fp, ntoken, MAXTOKEN);
        if (*ntype == LEFTPAREN){
	    tcp->ranges = parse_ranges(fp, &tcp->ranges);
            *ntype = get_token(fp, ntoken, MAXTOKEN);
        } else if (*ntype == LEFTBRACKET) {
            /* if there is an enumeration list, parse it */
            tcp->enums = parse_enumlist(fp, &tcp->enums);
            *ntype = get_token(fp, ntoken, MAXTOKEN);
        }
        return NULL;
    }
}


/*
 * Parses an OBJECT TYPE macro.
 * Returns 0 on error.
 */
static struct node *
parse_objecttype(FILE *fp,
		 char *name)
{
    register int type;
    char token[MAXTOKEN];
    char nexttoken[MAXTOKEN];
    char quoted_string_buffer[MAXQUOTESTR];
    int nexttype, tctype;
    register struct node *np;

    type = get_token(fp, token, MAXTOKEN);
    if (type != SYNTAX){
        print_error("Bad format for OBJECT-TYPE", token, type);
        return NULL;
    }
    np = alloc_node(current_module);
    if (np == NULL) return(NULL);
    type = get_token(fp, token, MAXTOKEN);
    if (type == LABEL){
        int tmp_index;
        tctype = get_tc(token, current_module, &tmp_index,
                        &np->enums, &np->ranges, &np->hint);
        if (tctype == LABEL &&
            ds_get_int(DS_LIBRARY_ID, DS_LIB_MIB_WARNINGS) > 1){
            print_error("Warning: No known translation for type", token, type);
        }
        type = tctype;
        np->tc_index = tmp_index; /* store TC for later reference */
    }
    np->type = type;
    nexttype = get_token(fp, nexttoken, MAXTOKEN);
    switch(type){
        case SEQUENCE:
            if (nexttype == OF){
                nexttype = get_token(fp, nexttoken, MAXTOKEN);
                nexttype = get_token(fp, nexttoken, MAXTOKEN);
            }
            break;
        case INTEGER:
        case UINTEGER32:
        case COUNTER:
        case GAUGE:
        case BITSTRING:
        case LABEL:
            if (nexttype == LEFTBRACKET) {
                /* if there is an enumeration list, parse it */
                np->enums = parse_enumlist(fp, &np->enums);
                nexttype = get_token(fp, nexttoken, MAXTOKEN);
            } else if (nexttype == LEFTPAREN){
                /* if there is a range list, parse it */
		np->ranges = parse_ranges(fp, &np->ranges);
                nexttype = get_token(fp, nexttoken, MAXTOKEN);
            }
            break;
        case OCTETSTR:
        case KW_OPAQUE:
            /* parse any SIZE specification */
            if (nexttype == LEFTPAREN) {
                nexttype = get_token(fp, nexttoken, MAXTOKEN);
                if (nexttype == SIZE) {
                    nexttype = get_token(fp, nexttoken, MAXTOKEN);
                    if (nexttype == LEFTPAREN) {
			np->ranges = parse_ranges(fp, &np->ranges);
                        nexttype = get_token(fp, nexttoken, MAXTOKEN); /* ) */
                        if (nexttype == RIGHTPAREN)
                        {
                            nexttype = get_token(fp, nexttoken, MAXTOKEN);
                            break;
                        }
                    }
                }
                print_error("Bad SIZE syntax", token, type);
                free_node(np);
                return NULL;
            }
            break;
        case OBJID:
        case NETADDR:
        case IPADDR:
        case TIMETICKS:
        case NUL:
        case NSAPADDRESS:
        case COUNTER64:
            break;
        default:
            print_error("Bad syntax", token, type);
            free_node(np);
            return NULL;
    }
    if (nexttype == UNITS){
        type = get_token(fp, quoted_string_buffer, MAXQUOTESTR);
        if (type != QUOTESTRING) {
            print_error("Bad UNITS", quoted_string_buffer, type);
            free_node(np);
            return NULL;
        }
	np->units = strdup (quoted_string_buffer);
        nexttype = get_token(fp, nexttoken, MAXTOKEN);
    }
    if (nexttype != ACCESS){
        print_error("Should be ACCESS", nexttoken, nexttype);
        free_node(np);
        return NULL;
    }
    type = get_token(fp, token, MAXTOKEN);
    if (type != READONLY && type != READWRITE && type != WRITEONLY
        && type != NOACCESS && type != READCREATE && type != ACCNOTIFY){
        print_error("Bad ACCESS type", token, type);
        free_node(np);
        return NULL;
    }
    np->access = type;
    type = get_token(fp, token, MAXTOKEN);
    if (type != STATUS){
        print_error("Should be STATUS", token, type);
        free_node(np);
        return NULL;
    }
    type = get_token(fp, token, MAXTOKEN);
    if (type != MANDATORY && type != CURRENT && type != KW_OPTIONAL &&
        type != OBSOLETE && type != DEPRECATED){
        print_error("Bad STATUS", token, type);
        free_node(np);
        return NULL;
    }
    np->status = type;
    /*
     * Optional parts of the OBJECT-TYPE macro
     */
    type = get_token(fp, token, MAXTOKEN);
    while (type != EQUALS && type != ENDOFFILE) {
      switch (type) {
        case DESCRIPTION:
          type = get_token(fp, quoted_string_buffer, MAXQUOTESTR);
          if (type != QUOTESTRING) {
              print_error("Bad DESCRIPTION", quoted_string_buffer, type);
              free_node(np);
              return NULL;
          }
          if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_SAVE_MIB_DESCRS)) {
              np->description = strdup (quoted_string_buffer);
          }
          break;

        case REFERENCE:
          type = get_token(fp, quoted_string_buffer, MAXQUOTESTR);
          if (type != QUOTESTRING) {
              print_error("Bad REFERENCE", quoted_string_buffer, type);
              free_node(np);
              return NULL;
          }
          break;
        case INDEX:
          np->indexes = getIndexes(fp, &np->indexes);
          if (np->indexes == NULL) {
            print_error("Bad Index List",token,type);
            free_node(np);
            return NULL;
          }
          break;

        case DEFVAL:
        case AUGMENTS:
        case NUM_ENTRIES:
          if (tossObjectIdentifier(fp) != OBJID) {
              print_error("Bad Object Identifier", token, type);
              free_node(np);
              return NULL;
          }
          break;

        default:
          print_error("Bad format of optional clauses", token, type);
          free_node(np);
          return NULL;

      }
      type = get_token(fp, token, MAXTOKEN);
    }
    if (type != EQUALS){
        print_error("Bad format", token, type);
        free_node(np);