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Fix DDL table identifier parsing

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The parsing was inadequate and did not support all forms of quoted
identifiers.
This commit is contained in:
Markus Mäkelä 2018-01-26 13:50:06 +02:00
parent b7e475f316
commit 9146a215f7
3 changed files with 142 additions and 65 deletions
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30
server/modules/routing/avrorouter/avro_file.c
View File

@ -1067,6 +1067,9 @@ void handle_query_event(AVRO_INSTANCE *router, REP_HEADER *hdr, int *pending_tra
}
}
char ident[MYSQL_TABLE_MAXLEN + MYSQL_DATABASE_MAXLEN + 2];
read_table_identifier(db, sql, sql + len, ident, sizeof(ident));
if (is_create_table_statement(router, sql, len))
{
TABLE_CREATE *created = NULL;
@ -1086,7 +1089,7 @@ void handle_query_event(AVRO_INSTANCE *router, REP_HEADER *hdr, int *pending_tra
}
else
{
created = table_create_alloc(sql, len, db);
created = table_create_alloc(ident, sql, len, db);
}
if (created && !save_and_replace_table_create(router, created))
@ -1096,30 +1099,7 @@ void handle_query_event(AVRO_INSTANCE *router, REP_HEADER *hdr, int *pending_tra
}
else if (is_alter_table_statement(router, sql, len))
{
char ident[MYSQL_TABLE_MAXLEN + MYSQL_DATABASE_MAXLEN + 2];
read_alter_identifier(sql, sql + len, ident, sizeof(ident));
bool combine = (strnlen(db, 1) && strchr(ident, '.') == NULL);
size_t ident_len = strlen(ident) + 1; // + 1 for the NULL
if (combine)
{
ident_len += (strlen(db) + 1); // + 1 for the "."
}
char full_ident[ident_len];
full_ident[0] = 0; // Set full_ident to "".
if (combine)
{
strcat(full_ident, db);
strcat(full_ident, ".");
}
strcat(full_ident, ident);
TABLE_CREATE *created = hashtable_fetch(router->created_tables, full_ident);
TABLE_CREATE *created = hashtable_fetch(router->created_tables, ident);
if (created)
{

173
server/modules/routing/avrorouter/avro_schema.c
View File

@ -720,46 +720,28 @@ int resolve_table_version(const char* db, const char* table)
/**
* @brief Handle a query event which contains a CREATE TABLE statement
* @param sql Query SQL
* @param db Database where this query was executed
*
* @param ident Table identifier in database.table format
* @param sql The CREATE TABLE statement
* @param len Length of @c sql
*
* @return New CREATE_TABLE object or NULL if an error occurred
*/
TABLE_CREATE* table_create_alloc(const char* sql, int len, const char* db)
TABLE_CREATE* table_create_alloc(const char* ident, const char* sql, int len)
{
/** Extract the table definition so we can get the column names from it */
int stmt_len = 0;
const char* statement_sql = get_table_definition(sql, len, &stmt_len);
ss_dassert(statement_sql);
char* tbl_start = strchr(ident, '.');
ss_dassert(tbl_start);
*tbl_start++ = '\0';
char table[MYSQL_TABLE_MAXLEN + 1];
char database[MYSQL_DATABASE_MAXLEN + 1];
const char* err = NULL;
MXS_INFO("Create table: %.*s", len, sql);
if (!statement_sql)
{
err = "table definition";
}
else if (!get_table_name(sql, table))
{
err = "table name";
}
if (get_database_name(sql, database))
{
// The CREATE statement contains the database name
db = database;
}
else if (*db == '\0')
{
// No explicit or current database
err = "database name";
}
if (err)
{
MXS_ERROR("Malformed CREATE TABLE statement, could not extract %s: %.*s", err, len, sql);
return NULL;
}
strcpy(database, ident);
strcpy(table, tbl_start);
int* lengths = NULL;
char **names = NULL;
@ -1253,15 +1235,130 @@ static bool tok_eq(const char *a, const char *b, size_t len)
return true;
}
void read_alter_identifier(const char *sql, const char *end, char *dest, int size)
static void skip_whitespace(const char** saved)
{
int len = 0;
const char *tok = get_tok(sql, &len, end); // ALTER
if (tok && (tok = get_tok(tok + len, &len, end)) // TABLE
&& (tok = get_tok(tok + len, &len, end))) // Table identifier
const char* ptr = *saved;
while (*ptr && isspace(*ptr))
{
snprintf(dest, size, "%.*s", len, tok);
remove_backticks(dest);
ptr++;
}
*saved = ptr;
}
static void skip_token(const char** saved)
{
const char* ptr = *saved;
while (*ptr && !isspace(*ptr))
{
ptr++;
}
*saved = ptr;
}
static void skip_non_backtick(const char** saved)
{
const char* ptr = *saved;
while (*ptr && *ptr != '`')
{
ptr++;
}
*saved = ptr;
}
const char* keywords[] =
{
"CREATE",
"DROP",
"ALTER",
"IF",
"EXISTS",
"REPLACE",
"OR",
"TABLE",
"NOT",
NULL
};
static bool token_is_keyword(const char* tok, int len)
{
for (int i = 0; keywords[i]; i++)
{
if (strncasecmp(keywords[i], tok, len) == 0)
{
return true;
}
}
return false;
}
void read_table_identifier(const char* db, const char *sql, const char *end, char *dest, int size)
{
const char* start;
int len = 0;
bool is_keyword = true;
while (is_keyword)
{
skip_whitespace(&sql); // Leading whitespace
if (*sql == '`')
{
// Quoted identifier, not a keyword
is_keyword = false;
sql++;
start = sql;
skip_non_backtick(&sql);
len = sql - start;
sql++;
}
else
{
start = sql;
skip_token(&sql);
len = sql - start;
is_keyword = token_is_keyword(start, len);
}
}
skip_whitespace(&sql); // Space after first identifier
if (*sql != '.')
{
// No explicit database
snprintf(dest, size, "%s.%.*s", db, len, start);
}
else
{
// Explicit database, skip the period
sql++;
skip_whitespace(&sql); // Space after first identifier
const char* id_start;
int id_len = 0;
if (*sql == '`')
{
sql++;
id_start = sql;
skip_non_backtick(&sql);
id_len = sql - id_start;
sql++;
}
else
{
id_start = sql;
skip_token(&sql);
id_len = sql - id_start;
}
snprintf(dest, size, "%.*s.%.*s", len, start, id_len, id_start);
}
}

4
server/modules/routing/avrorouter/avrorouter.h
View File

@ -302,12 +302,12 @@ extern void read_table_info(uint8_t *ptr, uint8_t post_header_len, uint64_t *tab
char* dest, size_t len);
extern TABLE_MAP *table_map_alloc(uint8_t *ptr, uint8_t hdr_len, TABLE_CREATE* create);
extern void table_map_free(TABLE_MAP *map);
extern TABLE_CREATE* table_create_alloc(const char* sql, int len, const char* db);
extern TABLE_CREATE* table_create_alloc(const char* ident, const char* sql, int len, const char* db);
extern TABLE_CREATE* table_create_copy(AVRO_INSTANCE *router, const char* sql, size_t len, const char* db);
extern void table_create_free(TABLE_CREATE* value);
extern bool table_create_save(TABLE_CREATE *create, const char *filename);
extern bool table_create_alter(TABLE_CREATE *create, const char *sql, const char *end);
extern void read_alter_identifier(const char *sql, const char *end, char *dest, int size);
extern void read_table_identifier(const char* db, const char *sql, const char *end, char *dest, int size);
extern int avro_client_handle_request(AVRO_INSTANCE *, AVRO_CLIENT *, GWBUF *);
extern void avro_client_rotate(AVRO_INSTANCE *router, AVRO_CLIENT *client, uint8_t *ptr);
extern bool avro_open_binlog(const char *binlogdir, const char *file, int *fd);