{
        char *token;
 
-       if (read_expected(EVENT_ITEM, (char *)"name") < 0)
+       if (read_expected(EVENT_ITEM, "name") < 0)
                return NULL;
 
-       if (read_expected(EVENT_OP, (char *)":") < 0)
+       if (read_expected(EVENT_OP, ":") < 0)
                return NULL;
 
        if (read_expect_type(EVENT_ITEM, &token) < 0)
        char *token;
        int id;
 
-       if (read_expected_item(EVENT_ITEM, (char *)"ID") < 0)
+       if (read_expected_item(EVENT_ITEM, "ID") < 0)
                return -1;
 
-       if (read_expected(EVENT_OP, (char *)":") < 0)
+       if (read_expected(EVENT_OP, ":") < 0)
                return -1;
 
        if (read_expect_type(EVENT_ITEM, &token) < 0)
 
                count++;
 
-               if (test_type_token(type, token, EVENT_ITEM, (char *)"field"))
+               if (test_type_token(type, token, EVENT_ITEM, "field"))
                        goto fail;
                free_token(token);
 
                        type = read_token(&token);
                }
 
-               if (test_type_token(type, token, EVENT_OP, (char *)":") < 0)
+               if (test_type_token(type, token, EVENT_OP, ":") < 0)
                        return -1;
 
                if (read_expect_type(EVENT_ITEM, &token) < 0)
                                field->flags |= FIELD_IS_DYNAMIC;
                }
 
-               if (test_type_token(type, token,  EVENT_OP, (char *)";"))
+               if (test_type_token(type, token,  EVENT_OP, ";"))
                        goto fail;
                free_token(token);
 
-               if (read_expected(EVENT_ITEM, (char *)"offset") < 0)
+               if (read_expected(EVENT_ITEM, "offset") < 0)
                        goto fail_expect;
 
-               if (read_expected(EVENT_OP, (char *)":") < 0)
+               if (read_expected(EVENT_OP, ":") < 0)
                        goto fail_expect;
 
                if (read_expect_type(EVENT_ITEM, &token))
                field->offset = strtoul(token, NULL, 0);
                free_token(token);
 
-               if (read_expected(EVENT_OP, (char *)";") < 0)
+               if (read_expected(EVENT_OP, ";") < 0)
                        goto fail_expect;
 
-               if (read_expected(EVENT_ITEM, (char *)"size") < 0)
+               if (read_expected(EVENT_ITEM, "size") < 0)
                        goto fail_expect;
 
-               if (read_expected(EVENT_OP, (char *)":") < 0)
+               if (read_expected(EVENT_OP, ":") < 0)
                        goto fail_expect;
 
                if (read_expect_type(EVENT_ITEM, &token))
                field->size = strtoul(token, NULL, 0);
                free_token(token);
 
-               if (read_expected(EVENT_OP, (char *)";") < 0)
+               if (read_expected(EVENT_OP, ";") < 0)
                        goto fail_expect;
 
                type = read_token(&token);
                if (type != EVENT_NEWLINE) {
                        /* newer versions of the kernel have a "signed" type */
-                       if (test_type_token(type, token, EVENT_ITEM, (char *)"signed"))
+                       if (test_type_token(type, token, EVENT_ITEM, "signed"))
                                goto fail;
 
                        free_token(token);
 
-                       if (read_expected(EVENT_OP, (char *)":") < 0)
+                       if (read_expected(EVENT_OP, ":") < 0)
                                goto fail_expect;
 
                        if (read_expect_type(EVENT_ITEM, &token))
                        /* add signed type */
 
                        free_token(token);
-                       if (read_expected(EVENT_OP, (char *)";") < 0)
+                       if (read_expected(EVENT_OP, ";") < 0)
                                goto fail_expect;
 
                        if (read_expect_type(EVENT_NEWLINE, &token))
        char *token;
        int ret;
 
-       if (read_expected_item(EVENT_ITEM, (char *)"format") < 0)
+       if (read_expected_item(EVENT_ITEM, "format") < 0)
                return -1;
 
-       if (read_expected(EVENT_OP, (char *)":") < 0)
+       if (read_expected(EVENT_OP, ":") < 0)
                return -1;
 
        if (read_expect_type(EVENT_NEWLINE, &token))
 
        *tok = NULL;
        type = process_arg(event, left, &token);
-       if (test_type_token(type, token, EVENT_OP, (char *)":"))
+       if (test_type_token(type, token, EVENT_OP, ":"))
                goto out_free;
 
        arg->op.op = token;
 
        *tok = NULL;
        type = process_arg(event, arg, &token);
-       if (test_type_token(type, token, EVENT_OP, (char *)"]"))
+       if (test_type_token(type, token, EVENT_OP, "]"))
                goto out_free;
 
        top->op.right = arg;
        char *field;
        char *token;
 
-       if (read_expected(EVENT_OP, (char *)"->") < 0)
+       if (read_expected(EVENT_OP, "->") < 0)
                return EVENT_ERROR;
 
        if (read_expect_type(EVENT_ITEM, &token) < 0)
        do {
                free_token(token);
                type = read_token_item(&token);
-               if (test_type_token(type, token, EVENT_OP, (char *)"{"))
+               if (test_type_token(type, token, EVENT_OP, "{"))
                        break;
 
                arg = malloc_or_die(sizeof(*arg));
 
                free_token(token);
                type = process_arg(event, arg, &token);
-               if (test_type_token(type, token, EVENT_DELIM, (char *)","))
+               if (test_type_token(type, token, EVENT_DELIM, ","))
                        goto out_free;
 
                field = malloc_or_die(sizeof(*field));
 
                free_token(token);
                type = process_arg(event, arg, &token);
-               if (test_type_token(type, token, EVENT_OP, (char *)"}"))
+               if (test_type_token(type, token, EVENT_OP, "}"))
                        goto out_free;
 
                value = arg_eval(arg);
        memset(arg, 0, sizeof(*arg));
        arg->type = PRINT_FLAGS;
 
-       if (read_expected_item(EVENT_DELIM, (char *)"(") < 0)
+       if (read_expected_item(EVENT_DELIM, "(") < 0)
                return EVENT_ERROR;
 
        field = malloc_or_die(sizeof(*field));
 
        type = process_arg(event, field, &token);
-       if (test_type_token(type, token, EVENT_DELIM, (char *)","))
+       if (test_type_token(type, token, EVENT_DELIM, ","))
                goto out_free;
 
        arg->flags.field = field;
                type = read_token_item(&token);
        }
 
-       if (test_type_token(type, token, EVENT_DELIM, (char *)","))
+       if (test_type_token(type, token, EVENT_DELIM, ","))
                goto out_free;
 
        type = process_fields(event, &arg->flags.flags, &token);
-       if (test_type_token(type, token, EVENT_DELIM, (char *)")"))
+       if (test_type_token(type, token, EVENT_DELIM, ")"))
                goto out_free;
 
        free_token(token);
        memset(arg, 0, sizeof(*arg));
        arg->type = PRINT_SYMBOL;
 
-       if (read_expected_item(EVENT_DELIM, (char *)"(") < 0)
+       if (read_expected_item(EVENT_DELIM, "(") < 0)
                return EVENT_ERROR;
 
        field = malloc_or_die(sizeof(*field));
 
        type = process_arg(event, field, &token);
-       if (test_type_token(type, token, EVENT_DELIM, (char *)","))
+       if (test_type_token(type, token, EVENT_DELIM, ","))
                goto out_free;
 
        arg->symbol.field = field;
 
        type = process_fields(event, &arg->symbol.symbols, &token);
-       if (test_type_token(type, token, EVENT_DELIM, (char *)")"))
+       if (test_type_token(type, token, EVENT_DELIM, ")"))
                goto out_free;
 
        free_token(token);
        if (type == EVENT_ERROR)
                return EVENT_ERROR;
 
-       if (test_type_token(type, token, EVENT_DELIM, (char *)")")) {
+       if (test_type_token(type, token, EVENT_DELIM, ")")) {
                free_token(token);
                return EVENT_ERROR;
        }
        enum event_type type;
        char *token;
 
-       if (read_expected(EVENT_DELIM, (char *)"(") < 0)
+       if (read_expected(EVENT_DELIM, "(") < 0)
                return EVENT_ERROR;
 
        if (read_expect_type(EVENT_ITEM, &token) < 0)
        arg->string.string = token;
        arg->string.offset = -1;
 
-       if (read_expected(EVENT_DELIM, (char *)")") < 0)
+       if (read_expected(EVENT_DELIM, ")") < 0)
                return EVENT_ERROR;
 
        type = read_token(&token);
        char *token;
        int ret;
 
-       if (read_expected_item(EVENT_ITEM, (char *)"print") < 0)
+       if (read_expected_item(EVENT_ITEM, "print") < 0)
                return -1;
 
-       if (read_expected(EVENT_ITEM, (char *)"fmt") < 0)
+       if (read_expected(EVENT_ITEM, "fmt") < 0)
                return -1;
 
-       if (read_expected(EVENT_OP, (char *)":") < 0)
+       if (read_expected(EVENT_OP, ":") < 0)
                return -1;
 
        if (read_expect_type(EVENT_DQUOTE, &token) < 0)
                token = cat;
                goto concat;
        }
-                            
-       if (test_type_token(type, token, EVENT_DELIM, (char *)","))
+
+       if (test_type_token(type, token, EVENT_DELIM, ","))
                goto fail;
 
        free_token(token);
 }
 
 static int __parse_common(void *data, int *size, int *offset,
-                         char *name)
+                         const char *name)
 {
        int ret;
 
        static int type_size;
 
        return __parse_common(data, &type_size, &type_offset,
-                             (char *)"common_type");
+                             "common_type");
 }
 
 static int parse_common_pid(void *data)
        static int pid_size;
 
        return __parse_common(data, &pid_size, &pid_offset,
-                             (char *)"common_pid");
+                             "common_pid");
 }
 
 static int parse_common_pc(void *data)
        static int pc_size;
 
        return __parse_common(data, &pc_size, &pc_offset,
-                             (char *)"common_preempt_count");
+                             "common_preempt_count");
 }
 
 static int parse_common_flags(void *data)
        static int flags_size;
 
        return __parse_common(data, &flags_size, &flags_offset,
-                             (char *)"common_flags");
+                             "common_flags");
 }
 
 static int parse_common_lock_depth(void *data)
        int ret;
 
        ret = __parse_common(data, &ld_size, &ld_offset,
-                            (char *)"common_lock_depth");
+                            "common_lock_depth");
        if (ret < 0)
                return -1;
 
        }
 }
 
-static void parse_header_field(char *field,
+static void parse_header_field(const char *field,
                               int *offset, int *size)
 {
        char *token;
        int type;
 
-       if (read_expected(EVENT_ITEM, (char *)"field") < 0)
+       if (read_expected(EVENT_ITEM, "field") < 0)
                return;
-       if (read_expected(EVENT_OP, (char *)":") < 0)
+       if (read_expected(EVENT_OP, ":") < 0)
                return;
 
        /* type */
 
        if (read_expected(EVENT_ITEM, field) < 0)
                return;
-       if (read_expected(EVENT_OP, (char *)";") < 0)
+       if (read_expected(EVENT_OP, ";") < 0)
                return;
-       if (read_expected(EVENT_ITEM, (char *)"offset") < 0)
+       if (read_expected(EVENT_ITEM, "offset") < 0)
                return;
-       if (read_expected(EVENT_OP, (char *)":") < 0)
+       if (read_expected(EVENT_OP, ":") < 0)
                return;
        if (read_expect_type(EVENT_ITEM, &token) < 0)
                goto fail;
        *offset = atoi(token);
        free_token(token);
-       if (read_expected(EVENT_OP, (char *)";") < 0)
+       if (read_expected(EVENT_OP, ";") < 0)
                return;
-       if (read_expected(EVENT_ITEM, (char *)"size") < 0)
+       if (read_expected(EVENT_ITEM, "size") < 0)
                return;
-       if (read_expected(EVENT_OP, (char *)":") < 0)
+       if (read_expected(EVENT_OP, ":") < 0)
                return;
        if (read_expect_type(EVENT_ITEM, &token) < 0)
                goto fail;
        *size = atoi(token);
        free_token(token);
-       if (read_expected(EVENT_OP, (char *)";") < 0)
+       if (read_expected(EVENT_OP, ";") < 0)
                return;
        type = read_token(&token);
        if (type != EVENT_NEWLINE) {
                if (type != EVENT_ITEM)
                        goto fail;
 
-               if (strcmp(token, (char *)"signed") != 0)
+               if (strcmp(token, "signed") != 0)
                        goto fail;
 
                free_token(token);
 
-               if (read_expected(EVENT_OP, (char *)":") < 0)
+               if (read_expected(EVENT_OP, ":") < 0)
                        return;
 
                if (read_expect_type(EVENT_ITEM, &token))
                        goto fail;
 
                free_token(token);
-               if (read_expected(EVENT_OP, (char *)";") < 0)
+               if (read_expected(EVENT_OP, ";") < 0)
                        return;
 
                if (read_expect_type(EVENT_NEWLINE, &token))
 {
        init_input_buf(buf, size);
 
-       parse_header_field((char *)"timestamp", &header_page_ts_offset,
+       parse_header_field("timestamp", &header_page_ts_offset,
                           &header_page_ts_size);
-       parse_header_field((char *)"commit", &header_page_size_offset,
+       parse_header_field("commit", &header_page_size_offset,
                           &header_page_size_size);
-       parse_header_field((char *)"data", &header_page_data_offset,
+       parse_header_field("data", &header_page_data_offset,
                           &header_page_data_size);
 
        return 0;