void insert_tree_node(tree **root,int data) {
if(*root == NULL) {
*root = make_tree_node(data);
}else {
insert_tree_node(&((*root)->node),data);
}
}
/**
* Parse a table name
*
* @param sql Pointer to pointer to column list updated to point to the table name
* @return A tree of table names
*/
static MAXINFO_TREE *
parse_table_name(char **ptr)
{
int token;
char *text;
MAXINFO_TREE *tree = NULL;
*ptr = fetch_token(*ptr, &token, &text);
if (token == LT_STRING)
return make_tree_node(MAXOP_TABLE, text, NULL, NULL);
free(text);
return NULL;
}
/**
* Parse a column list, may be a * or a valid list of string name
* separated by a comma
*
* @param sql Pointer to pointer to column list updated to point to the table name
* @return A tree of column names
*/
static MAXINFO_TREE *
parse_column_list(char **ptr)
{
int token, lookahead;
char *text, *text2;
MAXINFO_TREE *tree = NULL;
MAXINFO_TREE * rval = NULL;
*ptr = fetch_token(*ptr, &token, &text);
*ptr = fetch_token(*ptr, &lookahead, &text2);
switch (token)
{
case LT_STRING:
switch (lookahead)
{
case LT_COMMA:
rval = make_tree_node(MAXOP_COLUMNS, text, NULL,
parse_column_list(ptr));
break;
case LT_FROM:
rval = make_tree_node(MAXOP_COLUMNS, text, NULL,
NULL);
break;
default:
break;
}
break;
case LT_STAR:
if (lookahead != LT_FROM)
rval = make_tree_node(MAXOP_ALL_COLUMNS, NULL, NULL,
NULL);
break;
default:
break;
}
free(text);
free(text2);
return rval;
}
/**
* Parse the remaining arguments as literals.
* @param tree Previous head of the parse tree
* @param min_args Minimum required number of arguments
* @param ptr Pointer to client command
* @param parse_error Pointer to parsing error to fill
* @return Parsed tree or NULL if parsing failed
*/
MAXINFO_TREE* maxinfo_parse_literals(MAXINFO_TREE *tree, int min_args, char *ptr,
PARSE_ERROR *parse_error)
{
int token;
MAXINFO_TREE* node = tree;
char *text;
for(int i = 0; i < min_args; i++)
{
if((ptr = fetch_token(ptr, &token, &text)) == NULL ||
(node->right = make_tree_node(MAXOP_LITERAL, text, NULL, NULL)) == NULL)
{
*parse_error = PARSE_SYNTAX_ERROR;
free_tree(tree);
if(ptr)
{
free(text);
}
return NULL;
}
node = node->right;
}
return tree;
}
/**
* Parse a SQL subset for the maxinfo plugin and return a parse tree
*
* @param sql The SQL query
* @return Parse tree or NULL on error
*/
MAXINFO_TREE *
maxinfo_parse(char *sql, PARSE_ERROR *parse_error)
{
int token;
char *ptr, *text;
MAXINFO_TREE *tree = NULL;
MAXINFO_TREE *col, *table;
*parse_error = PARSE_NOERROR;
while ((ptr = fetch_token(sql, &token, &text)) != NULL)
{
switch (token)
{
case LT_SHOW:
free(text); // not needed
ptr = fetch_token(ptr, &token, &text);
if (ptr == NULL || token != LT_STRING)
{
// Expected show "name"
*parse_error = PARSE_MALFORMED_SHOW;
return NULL;
}
tree = make_tree_node(MAXOP_SHOW, text, NULL, NULL);
if ((ptr = fetch_token(ptr, &token, &text)) == NULL)
return tree;
else if (token == LT_LIKE)
{
if ((ptr = fetch_token(ptr, &token, &text)) != NULL)
{
tree->right = make_tree_node(MAXOP_LIKE,
text, NULL, NULL);
return tree;
}
else
{
// Expected expression
*parse_error = PARSE_EXPECTED_LIKE;
free_tree(tree);
return NULL;
}
}
// Malformed show
free(text);
free_tree(tree);
*parse_error = PARSE_MALFORMED_SHOW;
return NULL;
#if 0
case LT_SELECT:
free(text); // not needed
col = parse_column_list(&ptr);
table = parse_table_name(&ptr);
return make_tree_node(MAXOP_SELECT, NULL, col, table);
#endif
case LT_FLUSH:
free(text); // not needed
ptr = fetch_token(ptr, &token, &text);
return make_tree_node(MAXOP_FLUSH, text, NULL, NULL);
case LT_SHUTDOWN:
free(text);
ptr = fetch_token(ptr, &token, &text);
tree = make_tree_node(MAXOP_SHUTDOWN, text, NULL, NULL);
if ((ptr = fetch_token(ptr, &token, &text)) == NULL)
{
/** Possibly SHUTDOWN MAXSCALE */
return tree;
}
tree->right = make_tree_node(MAXOP_LITERAL, text, NULL, NULL);
if ((ptr = fetch_token(ptr, &token, &text)) != NULL)
{
/** Unknown token after SHUTDOWN MONITOR|SERVICE */
*parse_error = PARSE_SYNTAX_ERROR;
free_tree(tree);
return NULL;
}
return tree;
case LT_RESTART:
free(text);
ptr = fetch_token(ptr, &token, &text);
tree = make_tree_node(MAXOP_RESTART, text, NULL, NULL);
if ((ptr = fetch_token(ptr, &token, &text)) == NULL)
{
/** Missing token for RESTART MONITOR|SERVICE */
*parse_error = PARSE_SYNTAX_ERROR;
free_tree(tree);
return NULL;
}
tree->right = make_tree_node(MAXOP_LITERAL, text, NULL, NULL);
if ((ptr = fetch_token(ptr, &token, &text)) != NULL)
{
/** Unknown token after RESTART MONITOR|SERVICE */
*parse_error = PARSE_SYNTAX_ERROR;
free(text);
free_tree(tree);
return NULL;
}
return tree;
case LT_SET:
free(text); // not needed
ptr = fetch_token(ptr, &token, &text);
tree = make_tree_node(MAXOP_SET, text, NULL, NULL);
return maxinfo_parse_literals(tree, 2, ptr, parse_error);
case LT_CLEAR:
free(text); // not needed
ptr = fetch_token(ptr, &token, &text);
tree = make_tree_node(MAXOP_CLEAR, text, NULL, NULL);
return maxinfo_parse_literals(tree, 2, ptr, parse_error);
break;
default:
*parse_error = PARSE_SYNTAX_ERROR;
return NULL;
}
}
*parse_error = PARSE_SYNTAX_ERROR;
return NULL;
}
