GWBUF *gwbuf_clone_portion(
GWBUF *buf,
size_t start_offset,
size_t length)
{
GWBUF* clonebuf;
CHK_GWBUF(buf);
ss_dassert(start_offset+length <= GWBUF_LENGTH(buf));
if ((clonebuf = (GWBUF *)malloc(sizeof(GWBUF))) == NULL)
{
ss_dassert(clonebuf != NULL);
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error : Memory allocation failed due to %s.",
strerror(errno))));
return NULL;
}
atomic_add(&buf->sbuf->refcount, 1);
clonebuf->sbuf = buf->sbuf;
clonebuf->gwbuf_type = buf->gwbuf_type; /*< clone info bits too */
clonebuf->start = (void *)((char*)buf->start+start_offset);
clonebuf->end = (void *)((char *)clonebuf->start+length);
clonebuf->gwbuf_type = buf->gwbuf_type; /*< clone the type for now */
clonebuf->properties = NULL;
clonebuf->hint = NULL;
clonebuf->gwbuf_info = buf->gwbuf_info;
clonebuf->gwbuf_bufobj = buf->gwbuf_bufobj;
clonebuf->next = NULL;
clonebuf->tail = clonebuf;
CHK_GWBUF(clonebuf);
return clonebuf;
}
/**
* Trim bytes from the end of a GWBUF structure that may be the first
* in a list. If the buffer has n_bytes or less then it will be freed and
* the next buffer in the list will be returned, or if none, NULL.
*
* @param head The buffer to trim
* @param n_bytes The number of bytes to trim off
* @return The buffer chain or NULL if buffer chain now empty
*/
GWBUF *
gwbuf_rtrim(GWBUF *head, unsigned int n_bytes)
{
GWBUF *rval = head;
CHK_GWBUF(head);
GWBUF_RTRIM(head, n_bytes);
CHK_GWBUF(head);
if (GWBUF_EMPTY(head))
{
rval = head->next;
gwbuf_free(head);
}
return rval;
}
/**
* Consume data from a buffer in the linked list. The assumption is to consume
* n bytes from the buffer chain.
*
* If after consuming the bytes from the first buffer that buffer becomes
* empty it will be freed and the linked list updated.
*
* The return value is the new head of the linked list.
*
* This call should be made with the caller holding the lock for the linked
* list.
*
* @param head The head of the linked list
* @param length The amount of data to consume
* @return The head of the linked list
*/
GWBUF *
gwbuf_consume(GWBUF *head, unsigned int length)
{
GWBUF *rval = head;
CHK_GWBUF(head);
GWBUF_CONSUME(head, length);
CHK_GWBUF(head);
if (GWBUF_EMPTY(head))
{
rval = head->next;
gwbuf_free(head);
}
return rval;
}
/**
* Increment the usage count of a gateway buffer. This gets a new
* GWBUF structure that shares the actual data with the existing
* GWBUF structure but allows for the data copy to be avoided and
* also for each GWBUF to point to different portions of the same
* SHARED_BUF.
*
* @param buf The buffer to use
* @return A new GWBUF structure
*/
GWBUF *
gwbuf_clone(GWBUF *buf)
{
GWBUF *rval;
if ((rval = (GWBUF *)calloc(1,sizeof(GWBUF))) == NULL)
{
ss_dassert(rval != NULL);
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error : Memory allocation failed due to %s.",
strerror(errno))));
return NULL;
}
atomic_add(&buf->sbuf->refcount, 1);
rval->sbuf = buf->sbuf;
rval->start = buf->start;
rval->end = buf->end;
rval->gwbuf_type = buf->gwbuf_type;
rval->gwbuf_info = buf->gwbuf_info;
rval->gwbuf_bufobj = buf->gwbuf_bufobj;
rval->tail = rval;
CHK_GWBUF(rval);
return rval;
}
/**
* Append a buffer onto a linked list of buffer structures.
*
* This call should be made with the caller holding the lock for the linked
* list.
*
* @param head The current head of the linked list
* @param tail The new buffer to make the tail of the linked list
* @return The new head of the linked list
*/
GWBUF *
gwbuf_append(GWBUF *head, GWBUF *tail)
{
GWBUF *ptr = head;
if (!head)
return tail;
CHK_GWBUF(head);
CHK_GWBUF(tail);
while (ptr->next)
{
ptr = ptr->next;
}
ptr->next = tail;
return head;
}
/**
* Free a gateway buffer
*
* @param buf The buffer to free
*/
void
gwbuf_free(GWBUF *buf)
{
CHK_GWBUF(buf);
if (atomic_add(&buf->sbuf->refcount, -1) == 1)
{
free(buf->sbuf->data);
free(buf->sbuf);
}
free(buf);
}
/**
* Append a buffer onto a linked list of buffer structures.
*
* This call should be made with the caller holding the lock for the linked
* list.
*
* @param head The current head of the linked list
* @param tail The new buffer to make the tail of the linked list
* @return The new head of the linked list
*/
GWBUF *
gwbuf_append(GWBUF *head, GWBUF *tail)
{
if (!head)
return tail;
CHK_GWBUF(head);
head->tail->next = tail;
head->tail = tail->tail;
return head;
}
/**
* Consume data from a buffer in the linked list. The assumption is to consume
* n bytes from the buffer chain.
*
* If after consuming the bytes from the first buffer that buffer becomes
* empty it will be freed and the linked list updated.
*
* The return value is the new head of the linked list.
*
* This call should be made with the caller holding the lock for the linked
* list.
*
* @param head The head of the linked list
* @param length The amount of data to consume
* @return The head of the linked list
*/
GWBUF *
gwbuf_consume(GWBUF *head, unsigned int length)
{
GWBUF *rval = head;
CHK_GWBUF(head);
GWBUF_CONSUME(head, length);
CHK_GWBUF(head);
if (GWBUF_EMPTY(head))
{
rval = head->next;
if (head->next)
head->next->tail = head->tail;
gwbuf_free(head);
}
ss_dassert(rval == NULL || (rval->end > rval->start));
return rval;
}
/**
* Set given type to all buffers on the list.
* *
* @param buf The shared buffer
* @param type Type to be added
*/
void gwbuf_set_type(
GWBUF* buf,
gwbuf_type_t type)
{
/** Set type consistenly to all buffers on the list */
while (buf != NULL)
{
CHK_GWBUF(buf);
buf->gwbuf_type |= type;
buf=buf->next;
}
}
/**
* Return the number of bytes of data in the linked list.
*
* @param head The current head of the linked list
* @return The number of bytes of data in the linked list
*/
unsigned int
gwbuf_length(GWBUF *head)
{
int rval = 0;
CHK_GWBUF(head);
while (head)
{
rval += GWBUF_LENGTH(head);
head = head->next;
}
return rval;
}
/**
* Allocate a new gateway buffer structure of size bytes.
*
* For now we allocate memory directly from malloc for buffer the management
* structure and the actual data buffer itself. We may swap at a future date
* to a more effecient mechanism.
*
* @param size The size in bytes of the data area required
* @return Pointer to the buffer structure or NULL if memory could not
* be allocated.
*/
GWBUF *
gwbuf_alloc(unsigned int size)
{
GWBUF *rval;
SHARED_BUF *sbuf;
/* Allocate the buffer header */
if ((rval = (GWBUF *)malloc(sizeof(GWBUF))) == NULL)
{
goto retblock;;
}
/* Allocate the shared data buffer */
if ((sbuf = (SHARED_BUF *)malloc(sizeof(SHARED_BUF))) == NULL)
{
free(rval);
rval = NULL;
goto retblock;
}
/* Allocate the space for the actual data */
if ((sbuf->data = (unsigned char *)malloc(size)) == NULL)
{
ss_dassert(sbuf->data != NULL);
free(rval);
free(sbuf);
rval = NULL;
goto retblock;
}
spinlock_init(&rval->gwbuf_lock);
rval->start = sbuf->data;
rval->end = (void *)((char *)rval->start+size);
sbuf->refcount = 1;
rval->sbuf = sbuf;
rval->next = NULL;
rval->tail = rval;
rval->hint = NULL;
rval->properties = NULL;
rval->gwbuf_type = GWBUF_TYPE_UNDEFINED;
rval->gwbuf_info = GWBUF_INFO_NONE;
rval->gwbuf_bufobj = NULL;
CHK_GWBUF(rval);
retblock:
if (rval == NULL)
{
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error : Memory allocation failed due to %s.",
strerror(errno))));
}
return rval;
}
GWBUF *gwbuf_clone_portion(
GWBUF *buf,
size_t start_offset,
size_t length)
{
GWBUF* clonebuf;
CHK_GWBUF(buf);
ss_dassert(start_offset+length <= GWBUF_LENGTH(buf));
if ((clonebuf = (GWBUF *)malloc(sizeof(GWBUF))) == NULL)
{
return NULL;
}
atomic_add(&buf->sbuf->refcount, 1);
clonebuf->sbuf = buf->sbuf;
clonebuf->start = (void *)((char*)buf->start)+start_offset;
clonebuf->end = (void *)((char *)clonebuf->start)+length;
clonebuf->gwbuf_type = buf->gwbuf_type; /*< clone the type for now */
clonebuf->next = NULL;
CHK_GWBUF(clonebuf);
return clonebuf;
}
/**
* Returns pointer to GWBUF of a requested type.
* As of 10.3.14 only MySQL to plain text conversion is supported.
* Return NULL if conversion between types is not supported or due lacking
* type information.
*/
GWBUF *gwbuf_clone_transform(
GWBUF * head,
gwbuf_type_t targettype)
{
gwbuf_type_t src_type;
GWBUF* clonebuf;
CHK_GWBUF(head);
src_type = head->gwbuf_type;
if (targettype == GWBUF_TYPE_UNDEFINED ||
src_type == GWBUF_TYPE_UNDEFINED ||
src_type == GWBUF_TYPE_PLAINSQL ||
targettype == src_type)
{
clonebuf = NULL;
goto return_clonebuf;
}
switch (src_type)
{
case GWBUF_TYPE_MYSQL:
if (targettype == GWBUF_TYPE_PLAINSQL)
{
/** Crete reference to string part of buffer */
clonebuf = gwbuf_clone_portion(
head,
5,
GWBUF_LENGTH(head)-5);
ss_dassert(clonebuf != NULL);
/** Overwrite the type with new format */
clonebuf->gwbuf_type = targettype;
}
else
{
clonebuf = NULL;
}
break;
default:
clonebuf = NULL;
break;
} /*< switch (src_type) */
return_clonebuf:
return clonebuf;
}
/**
* Returns pointer to GWBUF of a requested type.
* As of 10.3.14 only MySQL to plain text conversion is supported.
* Return NULL if conversion between types is not supported or due lacking
* type information.
*/
GWBUF *gwbuf_clone_transform(
GWBUF * head,
gwbuf_type_t targettype)
{
gwbuf_type_t src_type;
GWBUF* clonebuf;
CHK_GWBUF(head);
src_type = head->gwbuf_type;
if (targettype == GWBUF_TYPE_UNDEFINED ||
src_type == GWBUF_TYPE_UNDEFINED ||
src_type == GWBUF_TYPE_PLAINSQL ||
targettype == src_type)
{
clonebuf = NULL;
goto return_clonebuf;
}
if (GWBUF_IS_TYPE_MYSQL(head))
{
if (GWBUF_TYPE_PLAINSQL == targettype)
{
/** Crete reference to string part of buffer */
clonebuf = gwbuf_clone_portion(
head,
5,
GWBUF_LENGTH(head)-5);
ss_dassert(clonebuf != NULL);
/** Overwrite the type with new format */
gwbuf_set_type(clonebuf, targettype);
}
else
{
clonebuf = NULL;
}
}
else
{
clonebuf = NULL;
}
return_clonebuf:
return clonebuf;
}
/**
* Increment the usage count of a gateway buffer. This gets a new
* GWBUF structure that shares the actual data with the existing
* GWBUF structure but allows for the data copy to be avoided and
* also for each GWBUF to point to different portions of the same
* SHARED_BUF.
*
* @param buf The buffer to use
* @return A new GWBUF structure
*/
GWBUF *
gwbuf_clone(GWBUF *buf)
{
GWBUF *rval;
if ((rval = (GWBUF *)malloc(sizeof(GWBUF))) == NULL)
{
return NULL;
}
atomic_add(&buf->sbuf->refcount, 1);
rval->sbuf = buf->sbuf;
rval->start = buf->start;
rval->end = buf->end;
rval->gwbuf_type = buf->gwbuf_type;
rval->next = NULL;
CHK_GWBUF(rval);
return rval;
}
/**
* Remove the first mysql statement from buffer. Return pointer to the removed
* statement or NULL if buffer is empty.
*
* Clone buf, calculate the length of included mysql stmt, and point the
* statement with cloned buffer. Move the start pointer of buf accordingly
* so that it only cover the remaining buffer.
*
*/
GWBUF* gw_MySQL_get_next_stmt(
GWBUF** p_readbuf)
{
GWBUF* stmtbuf;
size_t buflen;
size_t strlen;
uint8_t* packet;
if (*p_readbuf == NULL)
{
stmtbuf = NULL;
goto return_stmtbuf;
}
CHK_GWBUF(*p_readbuf);
if (GWBUF_EMPTY(*p_readbuf))
{
stmtbuf = NULL;
goto return_stmtbuf;
}
buflen = GWBUF_LENGTH((*p_readbuf));
packet = GWBUF_DATA((*p_readbuf));
strlen = MYSQL_GET_PACKET_LEN(packet);
if (strlen+4 == buflen)
{
stmtbuf = *p_readbuf;
*p_readbuf = NULL;
goto return_stmtbuf;
}
/** vraa :Multi-packet stmt is not supported as of 7.3.14 */
if (strlen-1 > buflen-5)
{
stmtbuf = NULL;
goto return_stmtbuf;
}
stmtbuf = gwbuf_clone_portion(*p_readbuf, 0, strlen+4);
*p_readbuf = gwbuf_consume(*p_readbuf, strlen+4);
return_stmtbuf:
return stmtbuf;
}
bool gwbuf_set_type(
GWBUF* buf,
gwbuf_type_t type)
{
bool succp;
CHK_GWBUF(buf);
switch (type) {
case GWBUF_TYPE_MYSQL:
case GWBUF_TYPE_PLAINSQL:
case GWBUF_TYPE_UNDEFINED:
buf->gwbuf_type = type;
succp = true;
break;
default:
succp = false;
break;
}
ss_dassert(succp);
return succp;
}
/**
* Search buffer object which matches with the id.
*
* @param buf GWBUF to be searched
* @param id Identifier for the object
*
* @return Searched buffer object or NULL if not found
*/
void* gwbuf_get_buffer_object_data(
GWBUF* buf,
bufobj_id_t id)
{
buffer_object_t* bo;
CHK_GWBUF(buf);
/** Lock */
spinlock_acquire(&buf->gwbuf_lock);
bo = buf->gwbuf_bufobj;
while (bo != NULL && bo->bo_id != id)
{
bo = bo->bo_next;
}
/** Unlock */
spinlock_release(&buf->gwbuf_lock);
if(bo) {
return bo->bo_data;
}
return NULL;
}
/**
* Add a buffer object to GWBUF buffer.
*
* @param buf GWBUF where object is added
* @param id Type identifier for object
* @param data Object data
* @param donefun_dp Clean-up function to be executed before buffer is freed.
*/
void gwbuf_add_buffer_object(
GWBUF* buf,
bufobj_id_t id,
void* data,
void (*donefun_fp)(void *))
{
buffer_object_t** p_b;
buffer_object_t* newb;
CHK_GWBUF(buf);
newb = (buffer_object_t *)malloc(sizeof(buffer_object_t));
ss_dassert(newb != NULL);
if (newb == NULL)
{
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"Error : Memory allocation failed due to %s.",
strerror(errno))));
return;
}
newb->bo_id = id;
newb->bo_data = data;
newb->bo_donefun_fp = donefun_fp;
newb->bo_next = NULL;
/** Lock */
spinlock_acquire(&buf->gwbuf_lock);
p_b = &buf->gwbuf_bufobj;
/** Search the end of the list and add there */
while (*p_b != NULL)
{
p_b = &(*p_b)->bo_next;
}
*p_b = newb;
/** Set flag */
buf->gwbuf_info |= GWBUF_INFO_PARSED;
/** Unlock */
spinlock_release(&buf->gwbuf_lock);
}
/**
* Free a gateway buffer
*
* @param buf The buffer to free
*/
void
gwbuf_free(GWBUF *buf)
{
BUF_PROPERTY *prop;
buffer_object_t* bo;
CHK_GWBUF(buf);
if (atomic_add(&buf->sbuf->refcount, -1) == 1)
{
free(buf->sbuf->data);
free(buf->sbuf);
bo = buf->gwbuf_bufobj;
while (bo != NULL)
{
bo = gwbuf_remove_buffer_object(buf, bo);
}
}
while (buf->properties)
{
prop = buf->properties;
buf->properties = prop->next;
free(prop->name);
free(prop->value);
free(prop);
}
/** Release the hint */
while (buf->hint)
{
HINT* h = buf->hint;
buf->hint = buf->hint->next;
hint_free(h);
}
free(buf);
}
/**
* Allocate a new gateway buffer structure of size bytes.
*
* For now we allocate memory directly from malloc for buffer the management
* structure and the actual data buffer itself. We may swap at a future date
* to a more effecient mechanism.
*
* @param size The size in bytes of the data area required
* @return Pointer to the buffer structure or NULL if memory could not
* be allocated.
*/
GWBUF *
gwbuf_alloc(unsigned int size)
{
GWBUF *rval;
SHARED_BUF *sbuf;
// Allocate the buffer header
if ((rval = (GWBUF *)malloc(sizeof(GWBUF))) == NULL)
{
return NULL;
}
// Allocate the shared data buffer
if ((sbuf = (SHARED_BUF *)malloc(sizeof(SHARED_BUF))) == NULL)
{
free(rval);
return NULL;
}
// Allocate the space for the actual data
if ((sbuf->data = (unsigned char *)malloc(size)) == NULL)
{
free(rval);
free(sbuf);
return NULL;
}
rval->start = sbuf->data;
rval->end = rval->start + size;
sbuf->refcount = 1;
rval->sbuf = sbuf;
rval->next = NULL;
rval->gwbuf_type = GWBUF_TYPE_UNDEFINED;
rval->command = 0;
CHK_GWBUF(rval);
return rval;
}
