postgresql/contrib/ltree/ltxtquery_io.c
Bruce Momjian b492c3accc Add parentheses to macros when args are used in computations. Without
them, the executation behavior could be unexpected.
2005-05-25 21:40:43 +00:00

519 lines
9.9 KiB
C

/*
* txtquery io
* Teodor Sigaev <teodor@stack.net>
*/
#include "ltree.h"
#include <ctype.h>
#include "crc32.h"
PG_FUNCTION_INFO_V1(ltxtq_in);
Datum ltxtq_in(PG_FUNCTION_ARGS);
PG_FUNCTION_INFO_V1(ltxtq_out);
Datum ltxtq_out(PG_FUNCTION_ARGS);
/* parser's states */
#define WAITOPERAND 1
#define INOPERAND 2
#define WAITOPERATOR 3
/*
* node of query tree, also used
* for storing polish notation in parser
*/
typedef struct NODE
{
int4 type;
int4 val;
int2 distance;
int2 length;
uint16 flag;
struct NODE *next;
} NODE;
typedef struct
{
char *buf;
int4 state;
int4 count;
/* reverse polish notation in list (for temporary usage) */
NODE *str;
/* number in str */
int4 num;
/* user-friendly operand */
int4 lenop;
int4 sumlen;
char *op;
char *curop;
} QPRS_STATE;
/*
* get token from query string
*/
static int4
gettoken_query(QPRS_STATE * state, int4 *val, int4 *lenval, char **strval, uint16 *flag)
{
while (1)
{
switch (state->state)
{
case WAITOPERAND:
if (*(state->buf) == '!')
{
(state->buf)++;
*val = (int4) '!';
return OPR;
}
else if (*(state->buf) == '(')
{
state->count++;
(state->buf)++;
return OPEN;
}
else if (ISALNUM(*(state->buf)))
{
state->state = INOPERAND;
*strval = state->buf;
*lenval = 1;
*flag = 0;
}
else if (!isspace((unsigned int) *(state->buf)))
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("operand syntax error")));
break;
case INOPERAND:
if (ISALNUM(*(state->buf)))
{
if (*flag)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("modificators syntax error")));
(*lenval)++;
}
else if (*(state->buf) == '%')
*flag |= LVAR_SUBLEXEM;
else if (*(state->buf) == '@')
*flag |= LVAR_INCASE;
else if (*(state->buf) == '*')
*flag |= LVAR_ANYEND;
else
{
state->state = WAITOPERATOR;
return VAL;
}
break;
case WAITOPERATOR:
if (*(state->buf) == '&' || *(state->buf) == '|')
{
state->state = WAITOPERAND;
*val = (int4) *(state->buf);
(state->buf)++;
return OPR;
}
else if (*(state->buf) == ')')
{
(state->buf)++;
state->count--;
return (state->count < 0) ? ERR : CLOSE;
}
else if (*(state->buf) == '\0')
return (state->count) ? ERR : END;
else if (*(state->buf) != ' ')
return ERR;
break;
default:
return ERR;
break;
}
(state->buf)++;
}
return END;
}
/*
* push new one in polish notation reverse view
*/
static void
pushquery(QPRS_STATE * state, int4 type, int4 val, int4 distance, int4 lenval, uint16 flag)
{
NODE *tmp = (NODE *) palloc(sizeof(NODE));
tmp->type = type;
tmp->val = val;
tmp->flag = flag;
if (distance > 0xffff)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("value is too big")));
if (lenval > 0xff)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("operand is too long")));
tmp->distance = distance;
tmp->length = lenval;
tmp->next = state->str;
state->str = tmp;
state->num++;
}
/*
* This function is used for query_txt parsing
*/
static void
pushval_asis(QPRS_STATE * state, int type, char *strval, int lenval, uint16 flag)
{
if (lenval > 0xffff)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("word is too long")));
pushquery(state, type, ltree_crc32_sz((uint8 *) strval, lenval),
state->curop - state->op, lenval, flag);
while (state->curop - state->op + lenval + 1 >= state->lenop)
{
int4 tmp = state->curop - state->op;
state->lenop *= 2;
state->op = (char *) repalloc((void *) state->op, state->lenop);
state->curop = state->op + tmp;
}
memcpy((void *) state->curop, (void *) strval, lenval);
state->curop += lenval;
*(state->curop) = '\0';
state->curop++;
state->sumlen += lenval + 1;
return;
}
#define STACKDEPTH 32
/*
* make polish notaion of query
*/
static int4
makepol(QPRS_STATE * state)
{
int4 val,
type;
int4 lenval;
char *strval;
int4 stack[STACKDEPTH];
int4 lenstack = 0;
uint16 flag;
while ((type = gettoken_query(state, &val, &lenval, &strval, &flag)) != END)
{
switch (type)
{
case VAL:
pushval_asis(state, VAL, strval, lenval, flag);
while (lenstack && (stack[lenstack - 1] == (int4) '&' ||
stack[lenstack - 1] == (int4) '!'))
{
lenstack--;
pushquery(state, OPR, stack[lenstack], 0, 0, 0);
}
break;
case OPR:
if (lenstack && val == (int4) '|')
pushquery(state, OPR, val, 0, 0, 0);
else
{
if (lenstack == STACKDEPTH)
/* internal error */
elog(ERROR, "stack too short");
stack[lenstack] = val;
lenstack++;
}
break;
case OPEN:
if (makepol(state) == ERR)
return ERR;
if (lenstack && (stack[lenstack - 1] == (int4) '&' ||
stack[lenstack - 1] == (int4) '!'))
{
lenstack--;
pushquery(state, OPR, stack[lenstack], 0, 0, 0);
}
break;
case CLOSE:
while (lenstack)
{
lenstack--;
pushquery(state, OPR, stack[lenstack], 0, 0, 0);
};
return END;
break;
case ERR:
default:
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("syntax error")));
return ERR;
}
}
while (lenstack)
{
lenstack--;
pushquery(state, OPR, stack[lenstack], 0, 0, 0);
};
return END;
}
static void
findoprnd(ITEM * ptr, int4 *pos)
{
if (ptr[*pos].type == VAL || ptr[*pos].type == VALTRUE)
{
ptr[*pos].left = 0;
(*pos)++;
}
else if (ptr[*pos].val == (int4) '!')
{
ptr[*pos].left = 1;
(*pos)++;
findoprnd(ptr, pos);
}
else
{
ITEM *curitem = &ptr[*pos];
int4 tmp = *pos;
(*pos)++;
findoprnd(ptr, pos);
curitem->left = *pos - tmp;
findoprnd(ptr, pos);
}
}
/*
* input
*/
static ltxtquery *
queryin(char *buf)
{
QPRS_STATE state;
int4 i;
ltxtquery *query;
int4 commonlen;
ITEM *ptr;
NODE *tmp;
int4 pos = 0;
#ifdef BS_DEBUG
char pbuf[16384],
*cur;
#endif
/* init state */
state.buf = buf;
state.state = WAITOPERAND;
state.count = 0;
state.num = 0;
state.str = NULL;
/* init list of operand */
state.sumlen = 0;
state.lenop = 64;
state.curop = state.op = (char *) palloc(state.lenop);
*(state.curop) = '\0';
/* parse query & make polish notation (postfix, but in reverse order) */
makepol(&state);
if (!state.num)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("syntax error"),
errdetail("Empty query.")));
/* make finish struct */
commonlen = COMPUTESIZE(state.num, state.sumlen);
query = (ltxtquery *) palloc(commonlen);
query->len = commonlen;
query->size = state.num;
ptr = GETQUERY(query);
/* set item in polish notation */
for (i = 0; i < state.num; i++)
{
ptr[i].type = state.str->type;
ptr[i].val = state.str->val;
ptr[i].distance = state.str->distance;
ptr[i].length = state.str->length;
ptr[i].flag = state.str->flag;
tmp = state.str->next;
pfree(state.str);
state.str = tmp;
}
/* set user friendly-operand view */
memcpy((void *) GETOPERAND(query), (void *) state.op, state.sumlen);
pfree(state.op);
/* set left operand's position for every operator */
pos = 0;
findoprnd(ptr, &pos);
return query;
}
/*
* in without morphology
*/
Datum
ltxtq_in(PG_FUNCTION_ARGS)
{
PG_RETURN_POINTER(queryin((char *) PG_GETARG_POINTER(0)));
}
/*
* out function
*/
typedef struct
{
ITEM *curpol;
char *buf;
char *cur;
char *op;
int4 buflen;
} INFIX;
#define RESIZEBUF(inf,addsize) \
while( ( (inf)->cur - (inf)->buf ) + (addsize) + 1 >= (inf)->buflen ) \
{ \
int4 len = (inf)->cur - (inf)->buf; \
(inf)->buflen *= 2; \
(inf)->buf = (char*) repalloc( (void*)(inf)->buf, (inf)->buflen ); \
(inf)->cur = (inf)->buf + len; \
}
/*
* recursive walk on tree and print it in
* infix (human-readable) view
*/
static void
infix(INFIX * in, bool first)
{
if (in->curpol->type == VAL)
{
char *op = in->op + in->curpol->distance;
RESIZEBUF(in, in->curpol->length * 2 + 5);
while (*op)
{
*(in->cur) = *op;
op++;
in->cur++;
}
if (in->curpol->flag & LVAR_SUBLEXEM)
{
*(in->cur) = '%';
in->cur++;
}
if (in->curpol->flag & LVAR_INCASE)
{
*(in->cur) = '@';
in->cur++;
}
if (in->curpol->flag & LVAR_ANYEND)
{
*(in->cur) = '*';
in->cur++;
}
*(in->cur) = '\0';
in->curpol++;
}
else if (in->curpol->val == (int4) '!')
{
bool isopr = false;
RESIZEBUF(in, 1);
*(in->cur) = '!';
in->cur++;
*(in->cur) = '\0';
in->curpol++;
if (in->curpol->type == OPR)
{
isopr = true;
RESIZEBUF(in, 2);
sprintf(in->cur, "( ");
in->cur = strchr(in->cur, '\0');
}
infix(in, isopr);
if (isopr)
{
RESIZEBUF(in, 2);
sprintf(in->cur, " )");
in->cur = strchr(in->cur, '\0');
}
}
else
{
int4 op = in->curpol->val;
INFIX nrm;
in->curpol++;
if (op == (int4) '|' && !first)
{
RESIZEBUF(in, 2);
sprintf(in->cur, "( ");
in->cur = strchr(in->cur, '\0');
}
nrm.curpol = in->curpol;
nrm.op = in->op;
nrm.buflen = 16;
nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen);
/* get right operand */
infix(&nrm, false);
/* get & print left operand */
in->curpol = nrm.curpol;
infix(in, false);
/* print operator & right operand */
RESIZEBUF(in, 3 + (nrm.cur - nrm.buf));
sprintf(in->cur, " %c %s", op, nrm.buf);
in->cur = strchr(in->cur, '\0');
pfree(nrm.buf);
if (op == (int4) '|' && !first)
{
RESIZEBUF(in, 2);
sprintf(in->cur, " )");
in->cur = strchr(in->cur, '\0');
}
}
}
Datum
ltxtq_out(PG_FUNCTION_ARGS)
{
ltxtquery *query = PG_GETARG_LTXTQUERY(0);
INFIX nrm;
if (query->size == 0)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("syntax error"),
errdetail("Empty query.")));
nrm.curpol = GETQUERY(query);
nrm.buflen = 32;
nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen);
*(nrm.cur) = '\0';
nrm.op = GETOPERAND(query);
infix(&nrm, true);
PG_FREE_IF_COPY(query, 0);
PG_RETURN_POINTER(nrm.buf);
}