queryjumblefuncs.c File Reference

#include "postgres.h"
#include "access/transam.h"
#include "catalog/pg_proc.h"
#include "common/hashfn.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
#include "nodes/queryjumble.h"
#include "utils/lsyscache.h"
#include "parser/scansup.h"
#include "queryjumblefuncs.funcs.c"
#include "queryjumblefuncs.switch.c"

Include dependency graph for queryjumblefuncs.c:

Go to the source code of this file.

Macros
#define	JUMBLE_SIZE   1024 /* query serialization buffer size */
#define	JUMBLE_NODE(item)    _jumbleNode(jstate, (Node *) expr->item)
#define	JUMBLE_ELEMENTS(list)    _jumbleElements(jstate, (List *) expr->list)
#define	JUMBLE_LOCATION(location)    RecordConstLocation(jstate, expr->location, false)
#define	JUMBLE_FIELD(item)
#define	JUMBLE_STRING(str)
#define	JUMBLE_CUSTOM(nodetype, item)    _jumble##nodetype##_##item(jstate, expr, expr->item)

Functions
static JumbleState *	InitJumble (void)
static uint64	DoJumble (JumbleState *jstate, Node *node)
static void	AppendJumble (JumbleState *jstate, const unsigned char *value, Size size)
static void	FlushPendingNulls (JumbleState *jstate)
static void	RecordConstLocation (JumbleState *jstate, int location, bool squashed)
static void	_jumbleNode (JumbleState *jstate, Node *node)
static void	_jumbleElements (JumbleState *jstate, List *elements)
static void	_jumbleA_Const (JumbleState *jstate, Node *node)
static void	_jumbleList (JumbleState *jstate, Node *node)
static void	_jumbleVariableSetStmt (JumbleState *jstate, Node *node)
static void	_jumbleRangeTblEntry_eref (JumbleState *jstate, RangeTblEntry *rte, Alias *expr)
const char *	CleanQuerytext (const char *query, int *location, int *len)
JumbleState *	JumbleQuery (Query *query)
void	EnableQueryId (void)
static pg_attribute_always_inline void	AppendJumbleInternal (JumbleState *jstate, const unsigned char *item, Size size)
static pg_attribute_always_inline void	AppendJumbleNull (JumbleState *jstate)
static pg_noinline void	AppendJumble8 (JumbleState *jstate, const unsigned char *value)
static pg_noinline void	AppendJumble16 (JumbleState *jstate, const unsigned char *value)
static pg_noinline void	AppendJumble32 (JumbleState *jstate, const unsigned char *value)
static pg_noinline void	AppendJumble64 (JumbleState *jstate, const unsigned char *value)
static bool	IsSquashableConst (Node *element)
static bool	IsSquashableConstList (List *elements, Node **firstExpr, Node **lastExpr)

Variables
int	compute_query_id = COMPUTE_QUERY_ID_AUTO
bool	query_id_enabled = false

Macro Definition Documentation

JUMBLE_CUSTOM

#define JUMBLE_CUSTOM	(		nodetype,
			item
	)		_jumble##nodetype##_##item(jstate, expr, expr->item)

Definition at line 514 of file queryjumblefuncs.c.

JUMBLE_ELEMENTS

#define JUMBLE_ELEMENTS

(

list

)

_jumbleElements(jstate, (List *) expr->list)

Definition at line 489 of file queryjumblefuncs.c.

JUMBLE_FIELD

#define JUMBLE_FIELD

(

item

)

Value:

do { \
    if (sizeof(expr->item) == 8) \
        AppendJumble64(jstate, (const unsigned char *) &(expr->item)); \
    else if (sizeof(expr->item) == 4) \
        AppendJumble32(jstate, (const unsigned char *) &(expr->item)); \
    else if (sizeof(expr->item) == 2) \
        AppendJumble16(jstate, (const unsigned char *) &(expr->item)); \
    else if (sizeof(expr->item) == 1) \
        AppendJumble8(jstate, (const unsigned char *) &(expr->item)); \
	else \
		AppendJumble(jstate, (const unsigned char *) &(expr->item), sizeof(expr->item)); \
} while (0)

Definition at line 493 of file queryjumblefuncs.c.

JUMBLE_LOCATION

#define JUMBLE_LOCATION

(

location

)

RecordConstLocation(jstate, expr->location, false)

Definition at line 491 of file queryjumblefuncs.c.

JUMBLE_NODE

#define JUMBLE_NODE

(

item

)

_jumbleNode(jstate, (Node *) expr->item)

Definition at line 487 of file queryjumblefuncs.c.

JUMBLE_SIZE

#define JUMBLE_SIZE   1024 /* query serialization buffer size */

Definition at line 44 of file queryjumblefuncs.c.

JUMBLE_STRING

#define JUMBLE_STRING

(

str

)

Value:

do { \
    if (expr->str) \
        AppendJumble(jstate, (const unsigned char *) (expr->str), strlen(expr->str) + 1); \
	else \
		AppendJumbleNull(jstate); \
} while(0)

Definition at line 506 of file queryjumblefuncs.c.

Function Documentation

_jumbleA_Const()

static void _jumbleA_Const ( JumbleState *  jstate, Node *  node  )

static

Definition at line 652 of file queryjumblefuncs.c.

{
    A_Const    *expr = (A_Const *) node;
 
    JUMBLE_FIELD(isnull);
    if (!expr->isnull)
    {
        JUMBLE_FIELD(val.node.type);
        switch (nodeTag(&expr->val))
        {
            case T_Integer:
                JUMBLE_FIELD(val.ival.ival);
                break;
            case T_Float:
                JUMBLE_STRING(val.fval.fval);
                break;
            case T_Boolean:
                JUMBLE_FIELD(val.boolval.boolval);
                break;
            case T_String:
                JUMBLE_STRING(val.sval.sval);
                break;
            case T_BitString:
                JUMBLE_STRING(val.bsval.bsval);
                break;
            default:
                elog(ERROR, "unrecognized node type: %d",
                     (int) nodeTag(&expr->val));
                break;
        }
    }
}

References elog, ERROR, A_Const::isnull, JUMBLE_FIELD, JUMBLE_STRING, nodeTag, A_Const::val, and val.

_jumbleElements()

static void _jumbleElements ( JumbleState *  jstate, List *  elements  )

static

Definition at line 526 of file queryjumblefuncs.c.

{
    Node       *first,
               *last;
 
    if (IsSquashableConstList(elements, &first, &last))
    {
        /*
         * If this list of elements is squashable, keep track of the location
         * of its first and last elements.  When reading back the locations
         * array, we'll see two consecutive locations with ->squashed set to
         * true, indicating the location of initial and final elements of this
         * list.
         *
         * For the limited set of cases we support now (implicit coerce via
         * FuncExpr, Const) it's fine to use exprLocation of the 'last'
         * expression, but if more complex composite expressions are to be
         * supported (e.g., OpExpr or FuncExpr as an explicit call), more
         * sophisticated tracking will be needed.
         */
        RecordConstLocation(jstate, exprLocation(first), true);
        RecordConstLocation(jstate, exprLocation(last), true);
    }
    else
    {
        _jumbleNode(jstate, (Node *) elements);
    }
}

References _jumbleNode(), exprLocation(), IsSquashableConstList(), and RecordConstLocation().

_jumbleList()

static void _jumbleList ( JumbleState *  jstate, Node *  node  )

static

Definition at line 621 of file queryjumblefuncs.c.

{
    List       *expr = (List *) node;
    ListCell   *l;
 
    switch (expr->type)
    {
        case T_List:
            foreach(l, expr)
                _jumbleNode(jstate, lfirst(l));
            break;
        case T_IntList:
            foreach(l, expr)
                AppendJumble32(jstate, (const unsigned char *) &lfirst_int(l));
            break;
        case T_OidList:
            foreach(l, expr)
                AppendJumble32(jstate, (const unsigned char *) &lfirst_oid(l));
            break;
        case T_XidList:
            foreach(l, expr)
                AppendJumble32(jstate, (const unsigned char *) &lfirst_xid(l));
            break;
        default:
            elog(ERROR, "unrecognized list node type: %d",
                 (int) expr->type);
            return;
    }
}

References _jumbleNode(), AppendJumble32(), elog, ERROR, lfirst, lfirst_int, lfirst_oid, lfirst_xid, and List::type.

Referenced by _jumbleNode().

_jumbleNode()

static void _jumbleNode ( JumbleState *  jstate, Node *  node  )

static

Definition at line 556 of file queryjumblefuncs.c.

{
    Node       *expr = node;
#ifdef USE_ASSERT_CHECKING
    Size        prev_jumble_len = jstate->total_jumble_len;
#endif
 
    if (expr == NULL)
    {
        AppendJumbleNull(jstate);
        return;
    }
 
    /* Guard against stack overflow due to overly complex expressions */
    check_stack_depth();
 
    /*
     * We always emit the node's NodeTag, then any additional fields that are
     * considered significant, and then we recurse to any child nodes.
     */
    JUMBLE_FIELD(type);
 
    switch (nodeTag(expr))
    {
#include "queryjumblefuncs.switch.c"
 
        case T_List:
        case T_IntList:
        case T_OidList:
        case T_XidList:
            _jumbleList(jstate, expr);
            break;
 
        default:
            /* Only a warning, since we can stumble along anyway */
            elog(WARNING, "unrecognized node type: %d",
                 (int) nodeTag(expr));
            break;
    }
 
    /* Special cases to handle outside the automated code */
    switch (nodeTag(expr))
    {
        case T_Param:
            {
                Param      *p = (Param *) node;
 
                /*
                 * Update the highest Param id seen, in order to start
                 * normalization correctly.
                 */
                if (p->paramkind == PARAM_EXTERN &&
                    p->paramid > jstate->highest_extern_param_id)
                    jstate->highest_extern_param_id = p->paramid;
            }
            break;
        default:
            break;
    }
 
    /* Ensure we added something to the jumble buffer */
    Assert(jstate->total_jumble_len > prev_jumble_len);
}

References _jumbleList(), AppendJumbleNull(), Assert(), check_stack_depth(), elog, JumbleState::highest_extern_param_id, JUMBLE_FIELD, nodeTag, PARAM_EXTERN, Param::paramid, Param::paramkind, type, and WARNING.

Referenced by _jumbleElements(), _jumbleList(), and DoJumble().

_jumbleRangeTblEntry_eref()

static void _jumbleRangeTblEntry_eref ( JumbleState *  jstate, RangeTblEntry *  rte, Alias *  expr  )

static

Definition at line 707 of file queryjumblefuncs.c.

{
    JUMBLE_FIELD(type);
 
    /*
     * This includes only the table name, the list of column names is ignored.
     */
    JUMBLE_STRING(aliasname);
}

References JUMBLE_FIELD, JUMBLE_STRING, and type.

_jumbleVariableSetStmt()

static void _jumbleVariableSetStmt ( JumbleState *  jstate, Node *  node  )

static

Definition at line 686 of file queryjumblefuncs.c.

{
    VariableSetStmt *expr = (VariableSetStmt *) node;
 
    JUMBLE_FIELD(kind);
    JUMBLE_STRING(name);
 
    /*
     * Account for the list of arguments in query jumbling only if told by the
     * parser.
     */
    if (expr->jumble_args)
        JUMBLE_NODE(args);
    JUMBLE_FIELD(is_local);
    JUMBLE_LOCATION(location);
}

References generate_unaccent_rules::args, VariableSetStmt::jumble_args, JUMBLE_FIELD, JUMBLE_LOCATION, JUMBLE_NODE, JUMBLE_STRING, and name.

AppendJumble()

static pg_noinline void AppendJumble ( JumbleState *  jstate, const unsigned char *  value, Size  size  )

static

Definition at line 285 of file queryjumblefuncs.c.

{
    if (jstate->pending_nulls > 0)
        FlushPendingNulls(jstate);
 
    AppendJumbleInternal(jstate, value, size);
}

References AppendJumbleInternal(), FlushPendingNulls(), JumbleState::pending_nulls, and value.

AppendJumble16()

static pg_noinline void AppendJumble16 ( JumbleState *  jstate, const unsigned char *  value  )

static

Definition at line 322 of file queryjumblefuncs.c.

{
    if (jstate->pending_nulls > 0)
        FlushPendingNulls(jstate);
 
    AppendJumbleInternal(jstate, value, 2);
}

References AppendJumbleInternal(), FlushPendingNulls(), JumbleState::pending_nulls, and value.

AppendJumble32()

static pg_noinline void AppendJumble32 ( JumbleState *  jstate, const unsigned char *  value  )

static

Definition at line 336 of file queryjumblefuncs.c.

{
    if (jstate->pending_nulls > 0)
        FlushPendingNulls(jstate);
 
    AppendJumbleInternal(jstate, value, 4);
}

References AppendJumbleInternal(), FlushPendingNulls(), JumbleState::pending_nulls, and value.

Referenced by _jumbleList().

AppendJumble64()

static pg_noinline void AppendJumble64 ( JumbleState *  jstate, const unsigned char *  value  )

static

Definition at line 350 of file queryjumblefuncs.c.

{
    if (jstate->pending_nulls > 0)
        FlushPendingNulls(jstate);
 
    AppendJumbleInternal(jstate, value, 8);
}

References AppendJumbleInternal(), FlushPendingNulls(), JumbleState::pending_nulls, and value.

AppendJumble8()

static pg_noinline void AppendJumble8 ( JumbleState *  jstate, const unsigned char *  value  )

static

Definition at line 308 of file queryjumblefuncs.c.

{
    if (jstate->pending_nulls > 0)
        FlushPendingNulls(jstate);
 
    AppendJumbleInternal(jstate, value, 1);
}

References AppendJumbleInternal(), FlushPendingNulls(), JumbleState::pending_nulls, and value.

AppendJumbleInternal()

static pg_attribute_always_inline void AppendJumbleInternal ( JumbleState *  jstate, const unsigned char *  item, Size  size  )

static

Definition at line 222 of file queryjumblefuncs.c.

{
    unsigned char *jumble = jstate->jumble;
    Size        jumble_len = jstate->jumble_len;
 
    /* Ensure the caller didn't mess up */
    Assert(size > 0);
 
    /*
     * Fast path for when there's enough space left in the buffer.  This is
     * worthwhile as means the memcpy can be inlined into very efficient code
     * when 'size' is a compile-time constant.
     */
    if (likely(size <= JUMBLE_SIZE - jumble_len))
    {
        memcpy(jumble + jumble_len, item, size);
        jstate->jumble_len += size;
 
#ifdef USE_ASSERT_CHECKING
        jstate->total_jumble_len += size;
#endif
 
        return;
    }
 
    /*
     * Whenever the jumble buffer is full, we hash the current contents and
     * reset the buffer to contain just that hash value, thus relying on the
     * hash to summarize everything so far.
     */
    do
    {
        Size        part_size;
 
        if (unlikely(jumble_len >= JUMBLE_SIZE))
        {
            uint64      start_hash;
 
            start_hash = DatumGetUInt64(hash_any_extended(jumble,
                                                          JUMBLE_SIZE, 0));
            memcpy(jumble, &start_hash, sizeof(start_hash));
            jumble_len = sizeof(start_hash);
        }
        part_size = Min(size, JUMBLE_SIZE - jumble_len);
        memcpy(jumble + jumble_len, item, part_size);
        jumble_len += part_size;
        item += part_size;
        size -= part_size;
 
#ifdef USE_ASSERT_CHECKING
        jstate->total_jumble_len += part_size;
#endif
    } while (size > 0);
 
    jstate->jumble_len = jumble_len;
}

References Assert(), DatumGetUInt64(), hash_any_extended(), JumbleState::jumble, JumbleState::jumble_len, JUMBLE_SIZE, likely, Min, and unlikely.

Referenced by AppendJumble(), AppendJumble16(), AppendJumble32(), AppendJumble64(), AppendJumble8(), and FlushPendingNulls().

AppendJumbleNull()

static pg_attribute_always_inline void AppendJumbleNull ( JumbleState *  jstate )

static

Definition at line 298 of file queryjumblefuncs.c.

{
    jstate->pending_nulls++;
}

References JumbleState::pending_nulls.

Referenced by _jumbleNode().

CleanQuerytext()

const char * CleanQuerytext	(	const char *	query,
		int *	location,
		int *	len
	)

Definition at line 79 of file queryjumblefuncs.c.

{
    int         query_location = *location;
    int         query_len = *len;
 
    /* First apply starting offset, unless it's -1 (unknown). */
    if (query_location >= 0)
    {
        Assert(query_location <= strlen(query));
        query += query_location;
        /* Length of 0 (or -1) means "rest of string" */
        if (query_len <= 0)
            query_len = strlen(query);
        else
            Assert(query_len <= strlen(query));
    }
    else
    {
        /* If query location is unknown, distrust query_len as well */
        query_location = 0;
        query_len = strlen(query);
    }
 
    /*
     * Discard leading and trailing whitespace, too.  Use scanner_isspace()
     * not libc's isspace(), because we want to match the lexer's behavior.
     *
     * Note: the parser now strips leading comments and whitespace from the
     * reported stmt_location, so this first loop will only iterate in the
     * unusual case that the location didn't propagate to here.  But the
     * statement length will extend to the end-of-string or terminating
     * semicolon, so the second loop often does something useful.
     */
    while (query_len > 0 && scanner_isspace(query[0]))
        query++, query_location++, query_len--;
    while (query_len > 0 && scanner_isspace(query[query_len - 1]))
        query_len--;
 
    *location = query_location;
    *len = query_len;
 
    return query;
}

References Assert(), len, and scanner_isspace().

Referenced by pgss_store(), and script_error_callback().

DoJumble()

static uint64 DoJumble ( JumbleState *  jstate, Node *  node  )

static

Definition at line 201 of file queryjumblefuncs.c.

{
    /* Jumble the given node */
    _jumbleNode(jstate, node);
 
    /* Flush any pending NULLs before doing the final hash */
    if (jstate->pending_nulls > 0)
        FlushPendingNulls(jstate);
 
    /* Process the jumble buffer and produce the hash value */
    return DatumGetUInt64(hash_any_extended(jstate->jumble,
                                            jstate->jumble_len,
                                            0));
}

References _jumbleNode(), DatumGetUInt64(), FlushPendingNulls(), hash_any_extended(), JumbleState::jumble, JumbleState::jumble_len, and JumbleState::pending_nulls.

Referenced by JumbleQuery().

EnableQueryId()

void EnableQueryId

(

void

)

Definition at line 162 of file queryjumblefuncs.c.

{
    if (compute_query_id != COMPUTE_QUERY_ID_OFF)
        query_id_enabled = true;
}

References compute_query_id, COMPUTE_QUERY_ID_OFF, and query_id_enabled.

Referenced by _PG_init().

FlushPendingNulls()

static pg_attribute_always_inline void FlushPendingNulls ( JumbleState *  jstate )

static

Definition at line 365 of file queryjumblefuncs.c.

{
    Assert(jstate->pending_nulls > 0);
 
    AppendJumbleInternal(jstate,
                         (const unsigned char *) &jstate->pending_nulls, 4);
    jstate->pending_nulls = 0;
}

References AppendJumbleInternal(), Assert(), and JumbleState::pending_nulls.

Referenced by AppendJumble(), AppendJumble16(), AppendJumble32(), AppendJumble64(), AppendJumble8(), and DoJumble().

InitJumble()

static JumbleState * InitJumble ( void  )

static

Definition at line 173 of file queryjumblefuncs.c.

{
    JumbleState *jstate;
 
    jstate = (JumbleState *) palloc(sizeof(JumbleState));
 
    /* Set up workspace for query jumbling */
    jstate->jumble = (unsigned char *) palloc(JUMBLE_SIZE);
    jstate->jumble_len = 0;
    jstate->clocations_buf_size = 32;
    jstate->clocations = (LocationLen *) palloc(jstate->clocations_buf_size *
                                                sizeof(LocationLen));
    jstate->clocations_count = 0;
    jstate->highest_extern_param_id = 0;
    jstate->pending_nulls = 0;
#ifdef USE_ASSERT_CHECKING
    jstate->total_jumble_len = 0;
#endif
 
    return jstate;
}

References JumbleState::clocations, JumbleState::clocations_buf_size, JumbleState::clocations_count, JumbleState::highest_extern_param_id, JumbleState::jumble, JumbleState::jumble_len, JUMBLE_SIZE, palloc(), and JumbleState::pending_nulls.

Referenced by JumbleQuery().

IsSquashableConst()

static bool IsSquashableConst ( Node *  element )

static

Definition at line 416 of file queryjumblefuncs.c.

{
    if (IsA(element, RelabelType))
        element = (Node *) ((RelabelType *) element)->arg;
 
    if (IsA(element, CoerceViaIO))
        element = (Node *) ((CoerceViaIO *) element)->arg;
 
    if (IsA(element, FuncExpr))
    {
        FuncExpr   *func = (FuncExpr *) element;
        ListCell   *temp;
 
        if (func->funcformat != COERCE_IMPLICIT_CAST &&
            func->funcformat != COERCE_EXPLICIT_CAST)
            return false;
 
        if (func->funcid > FirstGenbkiObjectId)
            return false;
 
        foreach(temp, func->args)
        {
            Node       *arg = lfirst(temp);
 
            if (!IsA(arg, Const))   /* XXX we could recurse here instead */
                return false;
        }
 
        return true;
    }
 
    if (!IsA(element, Const))
        return false;
 
    return true;
}

References arg, FuncExpr::args, COERCE_EXPLICIT_CAST, COERCE_IMPLICIT_CAST, element(), FirstGenbkiObjectId, FuncExpr::funcid, IsA, and lfirst.

Referenced by IsSquashableConstList().

IsSquashableConstList()

static bool IsSquashableConstList ( List *  elements, Node **  firstExpr, Node **  lastExpr  )

static

Definition at line 464 of file queryjumblefuncs.c.

{
    ListCell   *temp;
 
    /*
     * If squashing is disabled, or the list is too short, we don't try to
     * squash it.
     */
    if (list_length(elements) < 2)
        return false;
 
    foreach(temp, elements)
    {
        if (!IsSquashableConst(lfirst(temp)))
            return false;
    }
 
    *firstExpr = linitial(elements);
    *lastExpr = llast(elements);
 
    return true;
}

References IsSquashableConst(), lfirst, linitial, list_length(), and llast.

Referenced by _jumbleElements().

JumbleQuery()

JumbleState * JumbleQuery

(

Query *

query

)

Definition at line 130 of file queryjumblefuncs.c.

{
    JumbleState *jstate;
 
    Assert(IsQueryIdEnabled());
 
    jstate = InitJumble();
 
    query->queryId = DoJumble(jstate, (Node *) query);
 
    /*
     * If we are unlucky enough to get a hash of zero, use 1 instead for
     * normal statements and 2 for utility queries.
     */
    if (query->queryId == UINT64CONST(0))
    {
        if (query->utilityStmt)
            query->queryId = UINT64CONST(2);
        else
            query->queryId = UINT64CONST(1);
    }
 
    return jstate;
}

References Assert(), DoJumble(), InitJumble(), IsQueryIdEnabled(), UINT64CONST, and Query::utilityStmt.

Referenced by ExecCreateTableAs(), ExplainOneUtility(), ExplainQuery(), parse_analyze_fixedparams(), parse_analyze_varparams(), parse_analyze_withcb(), and PerformCursorOpen().

RecordConstLocation()

static void RecordConstLocation ( JumbleState *  jstate, int  location, bool  squashed  )

static

Definition at line 384 of file queryjumblefuncs.c.

{
    /* -1 indicates unknown or undefined location */
    if (location >= 0)
    {
        /* enlarge array if needed */
        if (jstate->clocations_count >= jstate->clocations_buf_size)
        {
            jstate->clocations_buf_size *= 2;
            jstate->clocations = (LocationLen *)
                repalloc(jstate->clocations,
                         jstate->clocations_buf_size *
                         sizeof(LocationLen));
        }
        jstate->clocations[jstate->clocations_count].location = location;
        /* initialize lengths to -1 to simplify third-party module usage */
        jstate->clocations[jstate->clocations_count].squashed = squashed;
        jstate->clocations[jstate->clocations_count].length = -1;
        jstate->clocations_count++;
    }
}

References JumbleState::clocations, JumbleState::clocations_buf_size, JumbleState::clocations_count, LocationLen::length, LocationLen::location, repalloc(), and LocationLen::squashed.

Referenced by _jumbleElements().

Variable Documentation

compute_query_id

int compute_query_id = COMPUTE_QUERY_ID_AUTO

Definition at line 47 of file queryjumblefuncs.c.

Referenced by EnableQueryId(), ExplainPrintPlan(), and IsQueryIdEnabled().

query_id_enabled

bool query_id_enabled = false

Definition at line 56 of file queryjumblefuncs.c.

Referenced by EnableQueryId(), and IsQueryIdEnabled().