From 6e68ba6380dc825a242e7f0d0a53442bba3a4a61 Mon Sep 17 00:00:00 2001 From: Sutou Kouhei Date: Mon, 4 Dec 2023 12:32:54 +0900 Subject: [PATCH v8 01/10] Extract COPY TO format implementations This is a part of making COPY format extendable. See also these past discussions: * New Copy Formats - avro/orc/parquet: https://www.postgresql.org/message-id/flat/20180210151304.fonjztsynewldfba%40gmail.com * Make COPY extendable in order to support Parquet and other formats: https://www.postgresql.org/message-id/flat/CAJ7c6TM6Bz1c3F04Cy6%2BSzuWfKmr0kU8c_3Stnvh_8BR0D6k8Q%40mail.gmail.com This doesn't change the current behavior. This just introduces CopyToRoutine, which just has function pointers of format implementation like TupleTableSlotOps, and use it for existing "text", "csv" and "binary" format implementations. Note that CopyToRoutine can't be used from extensions yet because CopySend*() aren't exported yet. Extensions can't send formatted data to a destination without CopySend*(). They will be exported by subsequent patches. Here is a benchmark result with/without this change because there was a discussion that we should care about performance regression: https://www.postgresql.org/message-id/3741749.1655952719%40sss.pgh.pa.us > I think that step 1 ought to be to convert the existing formats into > plug-ins, and demonstrate that there's no significant loss of > performance. You can see that there is no significant loss of performance: Data: Random 32 bit integers: CREATE TABLE data (int32 integer); INSERT INTO data SELECT random() * 10000 FROM generate_series(1, ${n_records}); The number of records: 100K, 1M and 10M 100K without this change: format,elapsed time (ms) text,11.002 csv,11.696 binary,11.352 100K with this change: format,elapsed time (ms) text,100000,11.562 csv,100000,11.889 binary,100000,10.825 1M without this change: format,elapsed time (ms) text,108.359 csv,114.233 binary,111.251 1M with this change: format,elapsed time (ms) text,111.269 csv,116.277 binary,104.765 10M without this change: format,elapsed time (ms) text,1090.763 csv,1136.103 binary,1137.141 10M with this change: format,elapsed time (ms) text,1082.654 csv,1196.991 binary,1069.697 --- contrib/file_fdw/file_fdw.c | 2 +- src/backend/commands/copy.c | 43 +++- src/backend/commands/copyfrom.c | 2 +- src/backend/commands/copyto.c | 428 ++++++++++++++++++++------------ src/include/commands/copy.h | 7 +- src/include/commands/copyapi.h | 59 +++++ 6 files changed, 376 insertions(+), 165 deletions(-) create mode 100644 src/include/commands/copyapi.h diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c index 249d82d3a0..9e4e819858 100644 --- a/contrib/file_fdw/file_fdw.c +++ b/contrib/file_fdw/file_fdw.c @@ -329,7 +329,7 @@ file_fdw_validator(PG_FUNCTION_ARGS) /* * Now apply the core COPY code's validation logic for more checks. */ - ProcessCopyOptions(NULL, NULL, true, other_options); + ProcessCopyOptions(NULL, NULL, true, NULL, other_options); /* * Either filename or program option is required for file_fdw foreign diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c index cc0786c6f4..5f3697a5f9 100644 --- a/src/backend/commands/copy.c +++ b/src/backend/commands/copy.c @@ -442,6 +442,9 @@ defGetCopyOnErrorChoice(DefElem *def, ParseState *pstate, bool is_from) * a list of options. In that usage, 'opts_out' can be passed as NULL and * the collected data is just leaked until CurrentMemoryContext is reset. * + * 'cstate' is CopyToState* for !is_from, CopyFromState* for is_from. 'cstate' + * may be NULL. For example, file_fdw uses NULL. + * * Note that additional checking, such as whether column names listed in FORCE * QUOTE actually exist, has to be applied later. This just checks for * self-consistency of the options list. @@ -450,6 +453,7 @@ void ProcessCopyOptions(ParseState *pstate, CopyFormatOptions *opts_out, bool is_from, + void *cstate, List *options) { bool format_specified = false; @@ -464,7 +468,13 @@ ProcessCopyOptions(ParseState *pstate, opts_out->file_encoding = -1; - /* Extract options from the statement node tree */ + /* Text is the default format. */ + opts_out->to_routine = &CopyToRoutineText; + + /* + * Extract only the "format" option to detect target routine as the first + * step + */ foreach(option, options) { DefElem *defel = lfirst_node(DefElem, option); @@ -479,15 +489,29 @@ ProcessCopyOptions(ParseState *pstate, if (strcmp(fmt, "text") == 0) /* default format */ ; else if (strcmp(fmt, "csv") == 0) + { opts_out->csv_mode = true; + opts_out->to_routine = &CopyToRoutineCSV; + } else if (strcmp(fmt, "binary") == 0) + { opts_out->binary = true; + opts_out->to_routine = &CopyToRoutineBinary; + } else ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE), errmsg("COPY format \"%s\" not recognized", fmt), parser_errposition(pstate, defel->location))); } + } + /* Extract options except "format" from the statement node tree */ + foreach(option, options) + { + DefElem *defel = lfirst_node(DefElem, option); + + if (strcmp(defel->defname, "format") == 0) + continue; else if (strcmp(defel->defname, "freeze") == 0) { if (freeze_specified) @@ -616,11 +640,18 @@ ProcessCopyOptions(ParseState *pstate, opts_out->on_error = defGetCopyOnErrorChoice(defel, pstate, is_from); } else - ereport(ERROR, - (errcode(ERRCODE_SYNTAX_ERROR), - errmsg("option \"%s\" not recognized", - defel->defname), - parser_errposition(pstate, defel->location))); + { + bool processed = false; + + if (!is_from) + processed = opts_out->to_routine->CopyToProcessOption(cstate, defel); + if (!processed) + ereport(ERROR, + (errcode(ERRCODE_SYNTAX_ERROR), + errmsg("option \"%s\" not recognized", + defel->defname), + parser_errposition(pstate, defel->location))); + } } /* diff --git a/src/backend/commands/copyfrom.c b/src/backend/commands/copyfrom.c index 1fe70b9133..fb3d4d9296 100644 --- a/src/backend/commands/copyfrom.c +++ b/src/backend/commands/copyfrom.c @@ -1416,7 +1416,7 @@ BeginCopyFrom(ParseState *pstate, oldcontext = MemoryContextSwitchTo(cstate->copycontext); /* Extract options from the statement node tree */ - ProcessCopyOptions(pstate, &cstate->opts, true /* is_from */ , options); + ProcessCopyOptions(pstate, &cstate->opts, true /* is_from */ , cstate, options); /* Process the target relation */ cstate->rel = rel; diff --git a/src/backend/commands/copyto.c b/src/backend/commands/copyto.c index d3dc3fc854..6547b7c654 100644 --- a/src/backend/commands/copyto.c +++ b/src/backend/commands/copyto.c @@ -131,6 +131,275 @@ static void CopySendEndOfRow(CopyToState cstate); static void CopySendInt32(CopyToState cstate, int32 val); static void CopySendInt16(CopyToState cstate, int16 val); +/* + * CopyToRoutine implementations. + */ + +/* + * CopyToRoutine implementation for "text" and "csv". CopyToText*() + * refer cstate->opts.csv_mode and change their behavior. We can split this + * implementation and stop referring cstate->opts.csv_mode later. + */ + +/* All "text" and "csv" options are parsed in ProcessCopyOptions(). We may + * move the code to here later. */ +static bool +CopyToTextProcessOption(CopyToState cstate, DefElem *defel) +{ + return false; +} + +static int16 +CopyToTextGetFormat(CopyToState cstate) +{ + return 0; +} + +static void +CopyToTextSendEndOfRow(CopyToState cstate) +{ + switch (cstate->copy_dest) + { + case COPY_FILE: + /* Default line termination depends on platform */ +#ifndef WIN32 + CopySendChar(cstate, '\n'); +#else + CopySendString(cstate, "\r\n"); +#endif + break; + case COPY_FRONTEND: + /* The FE/BE protocol uses \n as newline for all platforms */ + CopySendChar(cstate, '\n'); + break; + default: + break; + } + CopySendEndOfRow(cstate); +} + +static void +CopyToTextStart(CopyToState cstate, TupleDesc tupDesc) +{ + int num_phys_attrs; + ListCell *cur; + + num_phys_attrs = tupDesc->natts; + /* Get info about the columns we need to process. */ + cstate->out_functions = (FmgrInfo *) palloc(num_phys_attrs * sizeof(FmgrInfo)); + foreach(cur, cstate->attnumlist) + { + int attnum = lfirst_int(cur); + Oid out_func_oid; + bool isvarlena; + Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1); + + getTypeOutputInfo(attr->atttypid, &out_func_oid, &isvarlena); + fmgr_info(out_func_oid, &cstate->out_functions[attnum - 1]); + } + + /* + * For non-binary copy, we need to convert null_print to file encoding, + * because it will be sent directly with CopySendString. + */ + if (cstate->need_transcoding) + cstate->opts.null_print_client = pg_server_to_any(cstate->opts.null_print, + cstate->opts.null_print_len, + cstate->file_encoding); + + /* if a header has been requested send the line */ + if (cstate->opts.header_line) + { + bool hdr_delim = false; + + foreach(cur, cstate->attnumlist) + { + int attnum = lfirst_int(cur); + char *colname; + + if (hdr_delim) + CopySendChar(cstate, cstate->opts.delim[0]); + hdr_delim = true; + + colname = NameStr(TupleDescAttr(tupDesc, attnum - 1)->attname); + + if (cstate->opts.csv_mode) + CopyAttributeOutCSV(cstate, colname, false, + list_length(cstate->attnumlist) == 1); + else + CopyAttributeOutText(cstate, colname); + } + + CopyToTextSendEndOfRow(cstate); + } +} + +static void +CopyToTextOneRow(CopyToState cstate, TupleTableSlot *slot) +{ + bool need_delim = false; + FmgrInfo *out_functions = cstate->out_functions; + ListCell *cur; + + foreach(cur, cstate->attnumlist) + { + int attnum = lfirst_int(cur); + Datum value = slot->tts_values[attnum - 1]; + bool isnull = slot->tts_isnull[attnum - 1]; + + if (need_delim) + CopySendChar(cstate, cstate->opts.delim[0]); + need_delim = true; + + if (isnull) + { + CopySendString(cstate, cstate->opts.null_print_client); + } + else + { + char *string; + + string = OutputFunctionCall(&out_functions[attnum - 1], value); + if (cstate->opts.csv_mode) + CopyAttributeOutCSV(cstate, string, + cstate->opts.force_quote_flags[attnum - 1], + list_length(cstate->attnumlist) == 1); + else + CopyAttributeOutText(cstate, string); + } + } + + CopyToTextSendEndOfRow(cstate); +} + +static void +CopyToTextEnd(CopyToState cstate) +{ +} + +/* + * CopyToRoutine implementation for "binary". + */ + +/* All "binary" options are parsed in ProcessCopyOptions(). We may move the + * code to here later. */ +static bool +CopyToBinaryProcessOption(CopyToState cstate, DefElem *defel) +{ + return false; +} + +static int16 +CopyToBinaryGetFormat(CopyToState cstate) +{ + return 1; +} + +static void +CopyToBinaryStart(CopyToState cstate, TupleDesc tupDesc) +{ + int num_phys_attrs; + ListCell *cur; + + num_phys_attrs = tupDesc->natts; + /* Get info about the columns we need to process. */ + cstate->out_functions = (FmgrInfo *) palloc(num_phys_attrs * sizeof(FmgrInfo)); + foreach(cur, cstate->attnumlist) + { + int attnum = lfirst_int(cur); + Oid out_func_oid; + bool isvarlena; + Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1); + + getTypeBinaryOutputInfo(attr->atttypid, &out_func_oid, &isvarlena); + fmgr_info(out_func_oid, &cstate->out_functions[attnum - 1]); + } + + { + /* Generate header for a binary copy */ + int32 tmp; + + /* Signature */ + CopySendData(cstate, BinarySignature, 11); + /* Flags field */ + tmp = 0; + CopySendInt32(cstate, tmp); + /* No header extension */ + tmp = 0; + CopySendInt32(cstate, tmp); + } +} + +static void +CopyToBinaryOneRow(CopyToState cstate, TupleTableSlot *slot) +{ + FmgrInfo *out_functions = cstate->out_functions; + ListCell *cur; + + /* Binary per-tuple header */ + CopySendInt16(cstate, list_length(cstate->attnumlist)); + + foreach(cur, cstate->attnumlist) + { + int attnum = lfirst_int(cur); + Datum value = slot->tts_values[attnum - 1]; + bool isnull = slot->tts_isnull[attnum - 1]; + + if (isnull) + { + CopySendInt32(cstate, -1); + } + else + { + bytea *outputbytes; + + outputbytes = SendFunctionCall(&out_functions[attnum - 1], value); + CopySendInt32(cstate, VARSIZE(outputbytes) - VARHDRSZ); + CopySendData(cstate, VARDATA(outputbytes), + VARSIZE(outputbytes) - VARHDRSZ); + } + } + + CopySendEndOfRow(cstate); +} + +static void +CopyToBinaryEnd(CopyToState cstate) +{ + /* Generate trailer for a binary copy */ + CopySendInt16(cstate, -1); + /* Need to flush out the trailer */ + CopySendEndOfRow(cstate); +} + +CopyToRoutine CopyToRoutineText = { + .CopyToProcessOption = CopyToTextProcessOption, + .CopyToGetFormat = CopyToTextGetFormat, + .CopyToStart = CopyToTextStart, + .CopyToOneRow = CopyToTextOneRow, + .CopyToEnd = CopyToTextEnd, +}; + +/* + * We can use the same CopyToRoutine for both of "text" and "csv" because + * CopyToText*() refer cstate->opts.csv_mode and change their behavior. We can + * split the implementations and stop referring cstate->opts.csv_mode later. + */ +CopyToRoutine CopyToRoutineCSV = { + .CopyToProcessOption = CopyToTextProcessOption, + .CopyToGetFormat = CopyToTextGetFormat, + .CopyToStart = CopyToTextStart, + .CopyToOneRow = CopyToTextOneRow, + .CopyToEnd = CopyToTextEnd, +}; + +CopyToRoutine CopyToRoutineBinary = { + .CopyToProcessOption = CopyToBinaryProcessOption, + .CopyToGetFormat = CopyToBinaryGetFormat, + .CopyToStart = CopyToBinaryStart, + .CopyToOneRow = CopyToBinaryOneRow, + .CopyToEnd = CopyToBinaryEnd, +}; /* * Send copy start/stop messages for frontend copies. These have changed @@ -141,7 +410,7 @@ SendCopyBegin(CopyToState cstate) { StringInfoData buf; int natts = list_length(cstate->attnumlist); - int16 format = (cstate->opts.binary ? 1 : 0); + int16 format = cstate->opts.to_routine->CopyToGetFormat(cstate); int i; pq_beginmessage(&buf, PqMsg_CopyOutResponse); @@ -198,16 +467,6 @@ CopySendEndOfRow(CopyToState cstate) switch (cstate->copy_dest) { case COPY_FILE: - if (!cstate->opts.binary) - { - /* Default line termination depends on platform */ -#ifndef WIN32 - CopySendChar(cstate, '\n'); -#else - CopySendString(cstate, "\r\n"); -#endif - } - if (fwrite(fe_msgbuf->data, fe_msgbuf->len, 1, cstate->copy_file) != 1 || ferror(cstate->copy_file)) @@ -242,10 +501,6 @@ CopySendEndOfRow(CopyToState cstate) } break; case COPY_FRONTEND: - /* The FE/BE protocol uses \n as newline for all platforms */ - if (!cstate->opts.binary) - CopySendChar(cstate, '\n'); - /* Dump the accumulated row as one CopyData message */ (void) pq_putmessage(PqMsg_CopyData, fe_msgbuf->data, fe_msgbuf->len); break; @@ -431,7 +686,7 @@ BeginCopyTo(ParseState *pstate, oldcontext = MemoryContextSwitchTo(cstate->copycontext); /* Extract options from the statement node tree */ - ProcessCopyOptions(pstate, &cstate->opts, false /* is_from */ , options); + ProcessCopyOptions(pstate, &cstate->opts, false /* is_from */ , cstate, options); /* Process the source/target relation or query */ if (rel) @@ -748,8 +1003,6 @@ DoCopyTo(CopyToState cstate) bool pipe = (cstate->filename == NULL && cstate->data_dest_cb == NULL); bool fe_copy = (pipe && whereToSendOutput == DestRemote); TupleDesc tupDesc; - int num_phys_attrs; - ListCell *cur; uint64 processed; if (fe_copy) @@ -759,32 +1012,11 @@ DoCopyTo(CopyToState cstate) tupDesc = RelationGetDescr(cstate->rel); else tupDesc = cstate->queryDesc->tupDesc; - num_phys_attrs = tupDesc->natts; cstate->opts.null_print_client = cstate->opts.null_print; /* default */ /* We use fe_msgbuf as a per-row buffer regardless of copy_dest */ cstate->fe_msgbuf = makeStringInfo(); - /* Get info about the columns we need to process. */ - cstate->out_functions = (FmgrInfo *) palloc(num_phys_attrs * sizeof(FmgrInfo)); - foreach(cur, cstate->attnumlist) - { - int attnum = lfirst_int(cur); - Oid out_func_oid; - bool isvarlena; - Form_pg_attribute attr = TupleDescAttr(tupDesc, attnum - 1); - - if (cstate->opts.binary) - getTypeBinaryOutputInfo(attr->atttypid, - &out_func_oid, - &isvarlena); - else - getTypeOutputInfo(attr->atttypid, - &out_func_oid, - &isvarlena); - fmgr_info(out_func_oid, &cstate->out_functions[attnum - 1]); - } - /* * Create a temporary memory context that we can reset once per row to * recover palloc'd memory. This avoids any problems with leaks inside @@ -795,57 +1027,7 @@ DoCopyTo(CopyToState cstate) "COPY TO", ALLOCSET_DEFAULT_SIZES); - if (cstate->opts.binary) - { - /* Generate header for a binary copy */ - int32 tmp; - - /* Signature */ - CopySendData(cstate, BinarySignature, 11); - /* Flags field */ - tmp = 0; - CopySendInt32(cstate, tmp); - /* No header extension */ - tmp = 0; - CopySendInt32(cstate, tmp); - } - else - { - /* - * For non-binary copy, we need to convert null_print to file - * encoding, because it will be sent directly with CopySendString. - */ - if (cstate->need_transcoding) - cstate->opts.null_print_client = pg_server_to_any(cstate->opts.null_print, - cstate->opts.null_print_len, - cstate->file_encoding); - - /* if a header has been requested send the line */ - if (cstate->opts.header_line) - { - bool hdr_delim = false; - - foreach(cur, cstate->attnumlist) - { - int attnum = lfirst_int(cur); - char *colname; - - if (hdr_delim) - CopySendChar(cstate, cstate->opts.delim[0]); - hdr_delim = true; - - colname = NameStr(TupleDescAttr(tupDesc, attnum - 1)->attname); - - if (cstate->opts.csv_mode) - CopyAttributeOutCSV(cstate, colname, false, - list_length(cstate->attnumlist) == 1); - else - CopyAttributeOutText(cstate, colname); - } - - CopySendEndOfRow(cstate); - } - } + cstate->opts.to_routine->CopyToStart(cstate, tupDesc); if (cstate->rel) { @@ -884,13 +1066,7 @@ DoCopyTo(CopyToState cstate) processed = ((DR_copy *) cstate->queryDesc->dest)->processed; } - if (cstate->opts.binary) - { - /* Generate trailer for a binary copy */ - CopySendInt16(cstate, -1); - /* Need to flush out the trailer */ - CopySendEndOfRow(cstate); - } + cstate->opts.to_routine->CopyToEnd(cstate); MemoryContextDelete(cstate->rowcontext); @@ -906,71 +1082,15 @@ DoCopyTo(CopyToState cstate) static void CopyOneRowTo(CopyToState cstate, TupleTableSlot *slot) { - bool need_delim = false; - FmgrInfo *out_functions = cstate->out_functions; MemoryContext oldcontext; - ListCell *cur; - char *string; MemoryContextReset(cstate->rowcontext); oldcontext = MemoryContextSwitchTo(cstate->rowcontext); - if (cstate->opts.binary) - { - /* Binary per-tuple header */ - CopySendInt16(cstate, list_length(cstate->attnumlist)); - } - /* Make sure the tuple is fully deconstructed */ slot_getallattrs(slot); - foreach(cur, cstate->attnumlist) - { - int attnum = lfirst_int(cur); - Datum value = slot->tts_values[attnum - 1]; - bool isnull = slot->tts_isnull[attnum - 1]; - - if (!cstate->opts.binary) - { - if (need_delim) - CopySendChar(cstate, cstate->opts.delim[0]); - need_delim = true; - } - - if (isnull) - { - if (!cstate->opts.binary) - CopySendString(cstate, cstate->opts.null_print_client); - else - CopySendInt32(cstate, -1); - } - else - { - if (!cstate->opts.binary) - { - string = OutputFunctionCall(&out_functions[attnum - 1], - value); - if (cstate->opts.csv_mode) - CopyAttributeOutCSV(cstate, string, - cstate->opts.force_quote_flags[attnum - 1], - list_length(cstate->attnumlist) == 1); - else - CopyAttributeOutText(cstate, string); - } - else - { - bytea *outputbytes; - - outputbytes = SendFunctionCall(&out_functions[attnum - 1], - value); - CopySendInt32(cstate, VARSIZE(outputbytes) - VARHDRSZ); - CopySendData(cstate, VARDATA(outputbytes), - VARSIZE(outputbytes) - VARHDRSZ); - } - } - } - - CopySendEndOfRow(cstate); + cstate->opts.to_routine->CopyToOneRow(cstate, slot); MemoryContextSwitchTo(oldcontext); } diff --git a/src/include/commands/copy.h b/src/include/commands/copy.h index b3da3cb0be..34bea880ca 100644 --- a/src/include/commands/copy.h +++ b/src/include/commands/copy.h @@ -14,6 +14,7 @@ #ifndef COPY_H #define COPY_H +#include "commands/copyapi.h" #include "nodes/execnodes.h" #include "nodes/parsenodes.h" #include "parser/parse_node.h" @@ -74,11 +75,11 @@ typedef struct CopyFormatOptions bool convert_selectively; /* do selective binary conversion? */ CopyOnErrorChoice on_error; /* what to do when error happened */ List *convert_select; /* list of column names (can be NIL) */ + CopyToRoutine *to_routine; /* callback routines for COPY TO */ } CopyFormatOptions; -/* These are private in commands/copy[from|to].c */ +/* This is private in commands/copyfrom.c */ typedef struct CopyFromStateData *CopyFromState; -typedef struct CopyToStateData *CopyToState; typedef int (*copy_data_source_cb) (void *outbuf, int minread, int maxread); typedef void (*copy_data_dest_cb) (void *data, int len); @@ -87,7 +88,7 @@ extern void DoCopy(ParseState *pstate, const CopyStmt *stmt, int stmt_location, int stmt_len, uint64 *processed); -extern void ProcessCopyOptions(ParseState *pstate, CopyFormatOptions *opts_out, bool is_from, List *options); +extern void ProcessCopyOptions(ParseState *pstate, CopyFormatOptions *opts_out, bool is_from, void *cstate, List *options); extern CopyFromState BeginCopyFrom(ParseState *pstate, Relation rel, Node *whereClause, const char *filename, bool is_program, copy_data_source_cb data_source_cb, List *attnamelist, List *options); diff --git a/src/include/commands/copyapi.h b/src/include/commands/copyapi.h new file mode 100644 index 0000000000..eb68f2fb7b --- /dev/null +++ b/src/include/commands/copyapi.h @@ -0,0 +1,59 @@ +/*------------------------------------------------------------------------- + * + * copyapi.h + * API for COPY TO/FROM handlers + * + * + * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * src/include/commands/copyapi.h + * + *------------------------------------------------------------------------- + */ +#ifndef COPYAPI_H +#define COPYAPI_H + +#include "executor/tuptable.h" +#include "nodes/parsenodes.h" + +/* This is private in commands/copyto.c */ +typedef struct CopyToStateData *CopyToState; + +typedef bool (*CopyToProcessOption_function) (CopyToState cstate, DefElem *defel); +typedef int16 (*CopyToGetFormat_function) (CopyToState cstate); +typedef void (*CopyToStart_function) (CopyToState cstate, TupleDesc tupDesc); +typedef void (*CopyToOneRow_function) (CopyToState cstate, TupleTableSlot *slot); +typedef void (*CopyToEnd_function) (CopyToState cstate); + +/* Routines for a COPY TO format implementation. */ +typedef struct CopyToRoutine +{ + /* + * Called for processing one COPY TO option. This will return false when + * the given option is invalid. + */ + CopyToProcessOption_function CopyToProcessOption; + + /* + * Called when COPY TO is started. This will return a format as int16 + * value. It's used for the CopyOutResponse message. + */ + CopyToGetFormat_function CopyToGetFormat; + + /* Called when COPY TO is started. This will send a header. */ + CopyToStart_function CopyToStart; + + /* Copy one row for COPY TO. */ + CopyToOneRow_function CopyToOneRow; + + /* Called when COPY TO is ended. This will send a trailer. */ + CopyToEnd_function CopyToEnd; +} CopyToRoutine; + +/* Built-in CopyToRoutine for "text", "csv" and "binary". */ +extern CopyToRoutine CopyToRoutineText; +extern CopyToRoutine CopyToRoutineCSV; +extern CopyToRoutine CopyToRoutineBinary; + +#endif /* COPYAPI_H */ -- 2.41.0