// Tokenize tapset
// Copyright (C) 2010 Red Hat, Inc.
//
// This file is part of systemtap, and is free software.  You can
// redistribute it and/or modify it under the terms of the GNU General
// Public License (GPL); either version 2, or (at your option) any
// later version.

%{
#define STAP_NEED_CONTEXT_TOKENIZE 1
%}

/**
 * sfunction tokenize - Return the next non-empty token in a string
 *
 * @input: string to tokenize. If empty, returns the next non-empty token
 * in the string passed in the previous call to tokenize().
 * @delim: set of characters that delimit the tokens
 * 
 * Description: This function returns the next non-empty token in the
 * given input string, where the tokens are delimited by characters in
 * the delim string.  If the input string is non-empty, it returns the
 * first token.  If the input string is empty, it returns the next
 * token in the string passed in the previous call to tokenize.
 * If no delimiter is found, the entire remaining input string is 
 * returned. It returns empty when no more tokens are available.
 */
function tokenize:string(input:string, delim:string)
%{ /* unprivileged */
	char *token = NULL;
	char *token_end = NULL;

	if (STAP_ARG_input[0]) {
		strncpy(CONTEXT->tok_str, STAP_ARG_input, MAXSTRINGLEN);
		CONTEXT->tok_start = &CONTEXT->tok_str[0];
		CONTEXT->tok_end = &CONTEXT->tok_str[0] + strlen(CONTEXT->tok_str);
	}
	do {
		token = strsep(& CONTEXT->tok_start, STAP_ARG_delim);
	} while (token && !token[0]);
	if (token) {
		token_end = (CONTEXT->tok_start ? CONTEXT->tok_start - 1 : CONTEXT->tok_end);
		memcpy(STAP_RETVALUE, token, token_end - token + 1);
	}
%}
