wparser.c

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/*-------------------------------------------------------------------------
 *
 * wparser.c
 *      Standard interface to word parser
 *
 * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
 *
 *
 * IDENTIFICATION
 *    src/backend/tsearch/wparser.c
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"
 
#include "catalog/namespace.h"
#include "catalog/pg_type.h"
#include "commands/defrem.h"
#include "common/jsonapi.h"
#include "funcapi.h"
#include "tsearch/ts_cache.h"
#include "tsearch/ts_utils.h"
#include "utils/builtins.h"
#include "utils/jsonfuncs.h"
#include "utils/varlena.h"
 
/******sql-level interface******/
 
typedef struct
{
    int         cur;
    LexDescr   *list;
} TSTokenTypeStorage;
 
/* state for ts_headline_json_* */
typedef struct HeadlineJsonState
{
    HeadlineParsedText *prs;
    TSConfigCacheEntry *cfg;
    TSParserCacheEntry *prsobj;
    TSQuery     query;
    List       *prsoptions;
    bool        transformed;
} HeadlineJsonState;
 
static text *headline_json_value(void *_state, char *elem_value, int elem_len);
 
static void
tt_setup_firstcall(FuncCallContext *funcctx, Oid prsid)
{
    TupleDesc   tupdesc;
    MemoryContext oldcontext;
    TSTokenTypeStorage *st;
    TSParserCacheEntry *prs = lookup_ts_parser_cache(prsid);
 
    if (!OidIsValid(prs->lextypeOid))
        elog(ERROR, "method lextype isn't defined for text search parser %u",
             prsid);
 
    oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
 
    st = (TSTokenTypeStorage *) palloc(sizeof(TSTokenTypeStorage));
    st->cur = 0;
    /* lextype takes one dummy argument */
    st->list = (LexDescr *) DatumGetPointer(OidFunctionCall1(prs->lextypeOid,
                                                             (Datum) 0));
    funcctx->user_fctx = (void *) st;
 
    tupdesc = CreateTemplateTupleDesc(3);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "tokid",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "alias",
                       TEXTOID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 3, "description",
                       TEXTOID, -1, 0);
 
    funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
    MemoryContextSwitchTo(oldcontext);
}
 
static Datum
tt_process_call(FuncCallContext *funcctx)
{
    TSTokenTypeStorage *st;
 
    st = (TSTokenTypeStorage *) funcctx->user_fctx;
    if (st->list && st->list[st->cur].lexid)
    {
        Datum       result;
        char       *values[3];
        char        txtid[16];
        HeapTuple   tuple;
 
        sprintf(txtid, "%d", st->list[st->cur].lexid);
        values[0] = txtid;
        values[1] = st->list[st->cur].alias;
        values[2] = st->list[st->cur].descr;
 
        tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
        result = HeapTupleGetDatum(tuple);
 
        pfree(values[1]);
        pfree(values[2]);
        st->cur++;
        return result;
    }
    return (Datum) 0;
}
 
Datum
ts_token_type_byid(PG_FUNCTION_ARGS)
{
    FuncCallContext *funcctx;
    Datum       result;
 
    if (SRF_IS_FIRSTCALL())
    {
        funcctx = SRF_FIRSTCALL_INIT();
        tt_setup_firstcall(funcctx, PG_GETARG_OID(0));
    }
 
    funcctx = SRF_PERCALL_SETUP();
 
    if ((result = tt_process_call(funcctx)) != (Datum) 0)
        SRF_RETURN_NEXT(funcctx, result);
    SRF_RETURN_DONE(funcctx);
}
 
Datum
ts_token_type_byname(PG_FUNCTION_ARGS)
{
    FuncCallContext *funcctx;
    Datum       result;
 
    if (SRF_IS_FIRSTCALL())
    {
        text       *prsname = PG_GETARG_TEXT_PP(0);
        Oid         prsId;
 
        funcctx = SRF_FIRSTCALL_INIT();
        prsId = get_ts_parser_oid(textToQualifiedNameList(prsname), false);
        tt_setup_firstcall(funcctx, prsId);
    }
 
    funcctx = SRF_PERCALL_SETUP();
 
    if ((result = tt_process_call(funcctx)) != (Datum) 0)
        SRF_RETURN_NEXT(funcctx, result);
    SRF_RETURN_DONE(funcctx);
}
 
typedef struct
{
    int         type;
    char       *lexeme;
} LexemeEntry;
 
typedef struct
{
    int         cur;
    int         len;
    LexemeEntry *list;
} PrsStorage;
 
 
static void
prs_setup_firstcall(FuncCallContext *funcctx, Oid prsid, text *txt)
{
    TupleDesc   tupdesc;
    MemoryContext oldcontext;
    PrsStorage *st;
    TSParserCacheEntry *prs = lookup_ts_parser_cache(prsid);
    char       *lex = NULL;
    int         llen = 0,
                type = 0;
    void       *prsdata;
 
    oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
 
    st = (PrsStorage *) palloc(sizeof(PrsStorage));
    st->cur = 0;
    st->len = 16;
    st->list = (LexemeEntry *) palloc(sizeof(LexemeEntry) * st->len);
 
    prsdata = (void *) DatumGetPointer(FunctionCall2(&prs->prsstart,
                                                     PointerGetDatum(VARDATA_ANY(txt)),
                                                     Int32GetDatum(VARSIZE_ANY_EXHDR(txt))));
 
    while ((type = DatumGetInt32(FunctionCall3(&prs->prstoken,
                                               PointerGetDatum(prsdata),
                                               PointerGetDatum(&lex),
                                               PointerGetDatum(&llen)))) != 0)
    {
        if (st->cur >= st->len)
        {
            st->len = 2 * st->len;
            st->list = (LexemeEntry *) repalloc(st->list, sizeof(LexemeEntry) * st->len);
        }
        st->list[st->cur].lexeme = palloc(llen + 1);
        memcpy(st->list[st->cur].lexeme, lex, llen);
        st->list[st->cur].lexeme[llen] = '\0';
        st->list[st->cur].type = type;
        st->cur++;
    }
 
    FunctionCall1(&prs->prsend, PointerGetDatum(prsdata));
 
    st->len = st->cur;
    st->cur = 0;
 
    funcctx->user_fctx = (void *) st;
    tupdesc = CreateTemplateTupleDesc(2);
    TupleDescInitEntry(tupdesc, (AttrNumber) 1, "tokid",
                       INT4OID, -1, 0);
    TupleDescInitEntry(tupdesc, (AttrNumber) 2, "token",
                       TEXTOID, -1, 0);
 
    funcctx->attinmeta = TupleDescGetAttInMetadata(tupdesc);
    MemoryContextSwitchTo(oldcontext);
}
 
static Datum
prs_process_call(FuncCallContext *funcctx)
{
    PrsStorage *st;
 
    st = (PrsStorage *) funcctx->user_fctx;
    if (st->cur < st->len)
    {
        Datum       result;
        char       *values[2];
        char        tid[16];
        HeapTuple   tuple;
 
        values[0] = tid;
        sprintf(tid, "%d", st->list[st->cur].type);
        values[1] = st->list[st->cur].lexeme;
        tuple = BuildTupleFromCStrings(funcctx->attinmeta, values);
        result = HeapTupleGetDatum(tuple);
 
        pfree(values[1]);
        st->cur++;
        return result;
    }
    return (Datum) 0;
}
 
Datum
ts_parse_byid(PG_FUNCTION_ARGS)
{
    FuncCallContext *funcctx;
    Datum       result;
 
    if (SRF_IS_FIRSTCALL())
    {
        text       *txt = PG_GETARG_TEXT_PP(1);
 
        funcctx = SRF_FIRSTCALL_INIT();
        prs_setup_firstcall(funcctx, PG_GETARG_OID(0), txt);
        PG_FREE_IF_COPY(txt, 1);
    }
 
    funcctx = SRF_PERCALL_SETUP();
 
    if ((result = prs_process_call(funcctx)) != (Datum) 0)
        SRF_RETURN_NEXT(funcctx, result);
    SRF_RETURN_DONE(funcctx);
}
 
Datum
ts_parse_byname(PG_FUNCTION_ARGS)
{
    FuncCallContext *funcctx;
    Datum       result;
 
    if (SRF_IS_FIRSTCALL())
    {
        text       *prsname = PG_GETARG_TEXT_PP(0);
        text       *txt = PG_GETARG_TEXT_PP(1);
        Oid         prsId;
 
        funcctx = SRF_FIRSTCALL_INIT();
        prsId = get_ts_parser_oid(textToQualifiedNameList(prsname), false);
        prs_setup_firstcall(funcctx, prsId, txt);
    }
 
    funcctx = SRF_PERCALL_SETUP();
 
    if ((result = prs_process_call(funcctx)) != (Datum) 0)
        SRF_RETURN_NEXT(funcctx, result);
    SRF_RETURN_DONE(funcctx);
}
 
Datum
ts_headline_byid_opt(PG_FUNCTION_ARGS)
{
    Oid         tsconfig = PG_GETARG_OID(0);
    text       *in = PG_GETARG_TEXT_PP(1);
    TSQuery     query = PG_GETARG_TSQUERY(2);
    text       *opt = (PG_NARGS() > 3 && PG_GETARG_POINTER(3)) ? PG_GETARG_TEXT_PP(3) : NULL;
    HeadlineParsedText prs;
    List       *prsoptions;
    text       *out;
    TSConfigCacheEntry *cfg;
    TSParserCacheEntry *prsobj;
 
    cfg = lookup_ts_config_cache(tsconfig);
    prsobj = lookup_ts_parser_cache(cfg->prsId);
 
    if (!OidIsValid(prsobj->headlineOid))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("text search parser does not support headline creation")));
 
    memset(&prs, 0, sizeof(HeadlineParsedText));
    prs.lenwords = 32;
    prs.words = (HeadlineWordEntry *) palloc(sizeof(HeadlineWordEntry) * prs.lenwords);
 
    hlparsetext(cfg->cfgId, &prs, query,
                VARDATA_ANY(in), VARSIZE_ANY_EXHDR(in));
 
    if (opt)
        prsoptions = deserialize_deflist(PointerGetDatum(opt));
    else
        prsoptions = NIL;
 
    FunctionCall3(&(prsobj->prsheadline),
                  PointerGetDatum(&prs),
                  PointerGetDatum(prsoptions),
                  PointerGetDatum(query));
 
    out = generateHeadline(&prs);
 
    PG_FREE_IF_COPY(in, 1);
    PG_FREE_IF_COPY(query, 2);
    if (opt)
        PG_FREE_IF_COPY(opt, 3);
    pfree(prs.words);
    pfree(prs.startsel);
    pfree(prs.stopsel);
 
    PG_RETURN_POINTER(out);
}
 
Datum
ts_headline_byid(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall3(ts_headline_byid_opt,
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1),
                                        PG_GETARG_DATUM(2)));
}
 
Datum
ts_headline(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall3(ts_headline_byid_opt,
                                        ObjectIdGetDatum(getTSCurrentConfig(true)),
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1)));
}
 
Datum
ts_headline_opt(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall4(ts_headline_byid_opt,
                                        ObjectIdGetDatum(getTSCurrentConfig(true)),
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1),
                                        PG_GETARG_DATUM(2)));
}
 
Datum
ts_headline_jsonb_byid_opt(PG_FUNCTION_ARGS)
{
    Oid         tsconfig = PG_GETARG_OID(0);
    Jsonb      *jb = PG_GETARG_JSONB_P(1);
    TSQuery     query = PG_GETARG_TSQUERY(2);
    text       *opt = (PG_NARGS() > 3 && PG_GETARG_POINTER(3)) ? PG_GETARG_TEXT_P(3) : NULL;
    Jsonb      *out;
    JsonTransformStringValuesAction action = (JsonTransformStringValuesAction) headline_json_value;
    HeadlineParsedText prs;
    HeadlineJsonState *state = palloc0(sizeof(HeadlineJsonState));
 
    memset(&prs, 0, sizeof(HeadlineParsedText));
    prs.lenwords = 32;
    prs.words = (HeadlineWordEntry *) palloc(sizeof(HeadlineWordEntry) * prs.lenwords);
 
    state->prs = &prs;
    state->cfg = lookup_ts_config_cache(tsconfig);
    state->prsobj = lookup_ts_parser_cache(state->cfg->prsId);
    state->query = query;
    if (opt)
        state->prsoptions = deserialize_deflist(PointerGetDatum(opt));
    else
        state->prsoptions = NIL;
 
    if (!OidIsValid(state->prsobj->headlineOid))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("text search parser does not support headline creation")));
 
    out = transform_jsonb_string_values(jb, state, action);
 
    PG_FREE_IF_COPY(jb, 1);
    PG_FREE_IF_COPY(query, 2);
    if (opt)
        PG_FREE_IF_COPY(opt, 3);
 
    pfree(prs.words);
 
    if (state->transformed)
    {
        pfree(prs.startsel);
        pfree(prs.stopsel);
    }
 
    PG_RETURN_JSONB_P(out);
}
 
Datum
ts_headline_jsonb(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall3(ts_headline_jsonb_byid_opt,
                                        ObjectIdGetDatum(getTSCurrentConfig(true)),
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1)));
}
 
Datum
ts_headline_jsonb_byid(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall3(ts_headline_jsonb_byid_opt,
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1),
                                        PG_GETARG_DATUM(2)));
}
 
Datum
ts_headline_jsonb_opt(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall4(ts_headline_jsonb_byid_opt,
                                        ObjectIdGetDatum(getTSCurrentConfig(true)),
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1),
                                        PG_GETARG_DATUM(2)));
}
 
Datum
ts_headline_json_byid_opt(PG_FUNCTION_ARGS)
{
    Oid         tsconfig = PG_GETARG_OID(0);
    text       *json = PG_GETARG_TEXT_P(1);
    TSQuery     query = PG_GETARG_TSQUERY(2);
    text       *opt = (PG_NARGS() > 3 && PG_GETARG_POINTER(3)) ? PG_GETARG_TEXT_P(3) : NULL;
    text       *out;
    JsonTransformStringValuesAction action = (JsonTransformStringValuesAction) headline_json_value;
 
    HeadlineParsedText prs;
    HeadlineJsonState *state = palloc0(sizeof(HeadlineJsonState));
 
    memset(&prs, 0, sizeof(HeadlineParsedText));
    prs.lenwords = 32;
    prs.words = (HeadlineWordEntry *) palloc(sizeof(HeadlineWordEntry) * prs.lenwords);
 
    state->prs = &prs;
    state->cfg = lookup_ts_config_cache(tsconfig);
    state->prsobj = lookup_ts_parser_cache(state->cfg->prsId);
    state->query = query;
    if (opt)
        state->prsoptions = deserialize_deflist(PointerGetDatum(opt));
    else
        state->prsoptions = NIL;
 
    if (!OidIsValid(state->prsobj->headlineOid))
        ereport(ERROR,
                (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
                 errmsg("text search parser does not support headline creation")));
 
    out = transform_json_string_values(json, state, action);
 
    PG_FREE_IF_COPY(json, 1);
    PG_FREE_IF_COPY(query, 2);
    if (opt)
        PG_FREE_IF_COPY(opt, 3);
    pfree(prs.words);
 
    if (state->transformed)
    {
        pfree(prs.startsel);
        pfree(prs.stopsel);
    }
 
    PG_RETURN_TEXT_P(out);
}
 
Datum
ts_headline_json(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall3(ts_headline_json_byid_opt,
                                        ObjectIdGetDatum(getTSCurrentConfig(true)),
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1)));
}
 
Datum
ts_headline_json_byid(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall3(ts_headline_json_byid_opt,
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1),
                                        PG_GETARG_DATUM(2)));
}
 
Datum
ts_headline_json_opt(PG_FUNCTION_ARGS)
{
    PG_RETURN_DATUM(DirectFunctionCall4(ts_headline_json_byid_opt,
                                        ObjectIdGetDatum(getTSCurrentConfig(true)),
                                        PG_GETARG_DATUM(0),
                                        PG_GETARG_DATUM(1),
                                        PG_GETARG_DATUM(2)));
}
 
 
/*
 * Return headline in text from, generated from a json(b) element
 */
static text *
headline_json_value(void *_state, char *elem_value, int elem_len)
{
    HeadlineJsonState *state = (HeadlineJsonState *) _state;
 
    HeadlineParsedText *prs = state->prs;
    TSConfigCacheEntry *cfg = state->cfg;
    TSParserCacheEntry *prsobj = state->prsobj;
    TSQuery     query = state->query;
    List       *prsoptions = state->prsoptions;
 
    prs->curwords = 0;
    hlparsetext(cfg->cfgId, prs, query, elem_value, elem_len);
    FunctionCall3(&(prsobj->prsheadline),
                  PointerGetDatum(prs),
                  PointerGetDatum(prsoptions),
                  PointerGetDatum(query));
 
    state->transformed = true;
    return generateHeadline(prs);
}