postgresql/src/backend/commands/copy.c

1964 lines
48 KiB
C

/*-------------------------------------------------------------------------
*
* copy.c
* Implements the COPY utility command.
*
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/copy.c,v 1.201 2003/05/16 02:40:19 momjian Exp $
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <errno.h>
#include <unistd.h>
#include <sys/stat.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include "access/genam.h"
#include "access/heapam.h"
#include "access/printtup.h"
#include "catalog/catname.h"
#include "catalog/index.h"
#include "catalog/namespace.h"
#include "catalog/pg_index.h"
#include "catalog/pg_shadow.h"
#include "catalog/pg_type.h"
#include "commands/copy.h"
#include "commands/trigger.h"
#include "executor/executor.h"
#include "libpq/libpq.h"
#include "libpq/pqformat.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "parser/parse_coerce.h"
#include "parser/parse_relation.h"
#include "rewrite/rewriteHandler.h"
#include "tcop/pquery.h"
#include "tcop/tcopprot.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/relcache.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
#define ISOCTAL(c) (((c) >= '0') && ((c) <= '7'))
#define OCTVALUE(c) ((c) - '0')
/*
* Represents the different source/dest cases we need to worry about at
* the bottom level
*/
typedef enum CopyDest
{
COPY_FILE, /* to/from file */
COPY_OLD_FE, /* to/from frontend (old protocol) */
COPY_NEW_FE /* to/from frontend (new protocol) */
} CopyDest;
/*
* Represents the type of data returned by CopyReadAttribute()
*/
typedef enum CopyReadResult
{
NORMAL_ATTR,
END_OF_LINE,
END_OF_FILE
} CopyReadResult;
/*
* Represents the end-of-line terminator of the input
*/
typedef enum EolType
{
EOL_UNKNOWN,
EOL_NL,
EOL_CR,
EOL_CRNL
} EolType;
/* non-export function prototypes */
static void CopyTo(Relation rel, List *attnumlist, bool binary, bool oids,
char *delim, char *null_print);
static void CopyFrom(Relation rel, List *attnumlist, bool binary, bool oids,
char *delim, char *null_print);
static char *CopyReadAttribute(const char *delim, CopyReadResult *result);
static Datum CopyReadBinaryAttribute(int column_no, FmgrInfo *flinfo,
Oid typelem, bool *isnull);
static void CopyAttributeOut(char *string, char *delim);
static List *CopyGetAttnums(Relation rel, List *attnamelist);
static const char BinarySignature[11] = "PGCOPY\n\377\r\n\0";
/*
* Static communication variables ... pretty grotty, but COPY has
* never been reentrant...
*/
static CopyDest copy_dest;
static FILE *copy_file; /* if copy_dest == COPY_FILE */
static StringInfo copy_msgbuf; /* if copy_dest == COPY_NEW_FE */
static bool fe_eof; /* true if detected end of copy data */
static EolType eol_type; /* EOL type of input */
static int copy_lineno; /* line number for error messages */
/*
* These static variables are used to avoid incurring overhead for each
* attribute processed. attribute_buf is reused on each CopyReadAttribute
* call to hold the string being read in. Under normal use it will soon
* grow to a suitable size, and then we will avoid palloc/pfree overhead
* for subsequent attributes. Note that CopyReadAttribute returns a pointer
* to attribute_buf's data buffer!
* encoding, if needed, can be set once at the start of the copy operation.
*/
static StringInfoData attribute_buf;
static int client_encoding;
static int server_encoding;
/*
* Internal communications functions
*/
static void SendCopyBegin(bool binary, int natts);
static void ReceiveCopyBegin(bool binary, int natts);
static void SendCopyEnd(bool binary);
static void CopySendData(void *databuf, int datasize);
static void CopySendString(const char *str);
static void CopySendChar(char c);
static void CopySendEndOfRow(bool binary);
static void CopyGetData(void *databuf, int datasize);
static int CopyGetChar(void);
#define CopyGetEof() (fe_eof)
static int CopyPeekChar(void);
static void CopyDonePeek(int c, bool pickup);
static void CopySendInt32(int32 val);
static int32 CopyGetInt32(void);
static void CopySendInt16(int16 val);
static int16 CopyGetInt16(void);
/*
* Send copy start/stop messages for frontend copies. These have changed
* in past protocol redesigns.
*/
static void
SendCopyBegin(bool binary, int natts)
{
if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3)
{
/* new way */
StringInfoData buf;
int16 format = (binary ? 1 : 0);
int i;
pq_beginmessage(&buf, 'H');
pq_sendbyte(&buf, format); /* overall format */
pq_sendint(&buf, natts, 2);
for (i = 0; i < natts; i++)
pq_sendint(&buf, format, 2); /* per-column formats */
pq_endmessage(&buf);
copy_dest = COPY_NEW_FE;
copy_msgbuf = makeStringInfo();
}
else if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 2)
{
/* old way */
if (binary)
elog(ERROR, "COPY BINARY is not supported to stdout or from stdin");
pq_putemptymessage('H');
/* grottiness needed for old COPY OUT protocol */
pq_startcopyout();
copy_dest = COPY_OLD_FE;
}
else
{
/* very old way */
if (binary)
elog(ERROR, "COPY BINARY is not supported to stdout or from stdin");
pq_putemptymessage('B');
/* grottiness needed for old COPY OUT protocol */
pq_startcopyout();
copy_dest = COPY_OLD_FE;
}
}
static void
ReceiveCopyBegin(bool binary, int natts)
{
if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 3)
{
/* new way */
StringInfoData buf;
int16 format = (binary ? 1 : 0);
int i;
pq_beginmessage(&buf, 'G');
pq_sendbyte(&buf, format); /* overall format */
pq_sendint(&buf, natts, 2);
for (i = 0; i < natts; i++)
pq_sendint(&buf, format, 2); /* per-column formats */
pq_endmessage(&buf);
copy_dest = COPY_NEW_FE;
copy_msgbuf = makeStringInfo();
}
else if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 2)
{
/* old way */
if (binary)
elog(ERROR, "COPY BINARY is not supported to stdout or from stdin");
pq_putemptymessage('G');
copy_dest = COPY_OLD_FE;
}
else
{
/* very old way */
if (binary)
elog(ERROR, "COPY BINARY is not supported to stdout or from stdin");
pq_putemptymessage('D');
copy_dest = COPY_OLD_FE;
}
/* We *must* flush here to ensure FE knows it can send. */
pq_flush();
}
static void
SendCopyEnd(bool binary)
{
if (copy_dest == COPY_NEW_FE)
{
if (binary)
{
/* Need to flush out file trailer word */
CopySendEndOfRow(true);
}
else
{
/* Shouldn't have any unsent data */
Assert(copy_msgbuf->len == 0);
}
/* Send Copy Done message */
pq_putemptymessage('c');
}
else
{
/* The FE/BE protocol uses \n as newline for all platforms */
CopySendData("\\.\n", 3);
pq_endcopyout(false);
}
}
/*----------
* CopySendData sends output data to the destination (file or frontend)
* CopySendString does the same for null-terminated strings
* CopySendChar does the same for single characters
* CopySendEndOfRow does the appropriate thing at end of each data row
*
* NB: no data conversion is applied by these functions
*----------
*/
static void
CopySendData(void *databuf, int datasize)
{
switch (copy_dest)
{
case COPY_FILE:
fwrite(databuf, datasize, 1, copy_file);
if (ferror(copy_file))
elog(ERROR, "CopySendData: %m");
break;
case COPY_OLD_FE:
if (pq_putbytes((char *) databuf, datasize))
{
/* no hope of recovering connection sync, so FATAL */
elog(FATAL, "CopySendData: connection lost");
}
break;
case COPY_NEW_FE:
appendBinaryStringInfo(copy_msgbuf, (char *) databuf, datasize);
break;
}
}
static void
CopySendString(const char *str)
{
CopySendData((void *) str, strlen(str));
}
static void
CopySendChar(char c)
{
CopySendData(&c, 1);
}
static void
CopySendEndOfRow(bool binary)
{
switch (copy_dest)
{
case COPY_FILE:
if (!binary)
{
/* Default line termination depends on platform */
#ifndef WIN32
CopySendChar('\n');
#else
CopySendString("\r\n");
#endif
}
break;
case COPY_OLD_FE:
/* The FE/BE protocol uses \n as newline for all platforms */
if (!binary)
CopySendChar('\n');
break;
case COPY_NEW_FE:
/* The FE/BE protocol uses \n as newline for all platforms */
if (!binary)
CopySendChar('\n');
/* Dump the accumulated row as one CopyData message */
(void) pq_putmessage('d', copy_msgbuf->data, copy_msgbuf->len);
/* Reset copy_msgbuf to empty */
copy_msgbuf->len = 0;
copy_msgbuf->data[0] = '\0';
break;
}
}
/*
* CopyGetData reads data from the source (file or frontend)
* CopyGetChar does the same for single characters
*
* CopyGetEof checks if EOF was detected by previous Get operation.
*
* Note: when copying from the frontend, we expect a proper EOF mark per
* protocol; if the frontend simply drops the connection, we raise error.
* It seems unwise to allow the COPY IN to complete normally in that case.
*
* NB: no data conversion is applied by these functions
*/
static void
CopyGetData(void *databuf, int datasize)
{
switch (copy_dest)
{
case COPY_FILE:
fread(databuf, datasize, 1, copy_file);
if (feof(copy_file))
fe_eof = true;
break;
case COPY_OLD_FE:
if (pq_getbytes((char *) databuf, datasize))
{
/* Only a \. terminator is legal EOF in old protocol */
elog(ERROR, "unexpected EOF on client connection");
}
break;
case COPY_NEW_FE:
while (datasize > 0 && !fe_eof)
{
int avail;
while (copy_msgbuf->cursor >= copy_msgbuf->len)
{
/* Try to receive another message */
int mtype;
mtype = pq_getbyte();
if (mtype == EOF)
elog(ERROR, "unexpected EOF on client connection");
if (pq_getmessage(copy_msgbuf, 0))
elog(ERROR, "unexpected EOF on client connection");
switch (mtype)
{
case 'd': /* CopyData */
break;
case 'c': /* CopyDone */
/* COPY IN correctly terminated by frontend */
fe_eof = true;
return;
case 'f': /* CopyFail */
elog(ERROR, "COPY IN failed: %s",
pq_getmsgstring(copy_msgbuf));
break;
default:
elog(ERROR, "unexpected message type %c during COPY IN",
mtype);
break;
}
}
avail = copy_msgbuf->len - copy_msgbuf->cursor;
if (avail > datasize)
avail = datasize;
pq_copymsgbytes(copy_msgbuf, databuf, avail);
databuf = (void *) ((char *) databuf + avail);
datasize =- avail;
}
break;
}
}
static int
CopyGetChar(void)
{
int ch;
switch (copy_dest)
{
case COPY_FILE:
ch = getc(copy_file);
break;
case COPY_OLD_FE:
ch = pq_getbyte();
if (ch == EOF)
{
/* Only a \. terminator is legal EOF in old protocol */
elog(ERROR, "unexpected EOF on client connection");
}
break;
case COPY_NEW_FE:
{
unsigned char cc;
CopyGetData(&cc, 1);
if (fe_eof)
ch = EOF;
else
ch = cc;
break;
}
default:
ch = EOF;
break;
}
if (ch == EOF)
fe_eof = true;
return ch;
}
/*
* CopyPeekChar reads a byte in "peekable" mode.
*
* after each call to CopyPeekChar, a call to CopyDonePeek _must_
* follow, unless EOF was returned.
*
* CopyDonePeek will either take the peeked char off the stream
* (if pickup is true) or leave it on the stream (if pickup is false).
*/
static int
CopyPeekChar(void)
{
int ch;
switch (copy_dest)
{
case COPY_FILE:
ch = getc(copy_file);
break;
case COPY_OLD_FE:
ch = pq_peekbyte();
if (ch == EOF)
{
/* Only a \. terminator is legal EOF in old protocol */
elog(ERROR, "unexpected EOF on client connection");
}
break;
case COPY_NEW_FE:
{
unsigned char cc;
CopyGetData(&cc, 1);
if (fe_eof)
ch = EOF;
else
ch = cc;
break;
}
default:
ch = EOF;
break;
}
if (ch == EOF)
fe_eof = true;
return ch;
}
static void
CopyDonePeek(int c, bool pickup)
{
if (fe_eof)
return; /* can't unget an EOF */
switch (copy_dest)
{
case COPY_FILE:
if (!pickup)
{
/* We don't want to pick it up - so put it back in there */
ungetc(c, copy_file);
}
/* If we wanted to pick it up, it's already done */
break;
case COPY_OLD_FE:
if (pickup)
{
/* We want to pick it up */
(void) pq_getbyte();
}
/* If we didn't want to pick it up, just leave it where it sits */
break;
case COPY_NEW_FE:
if (!pickup)
{
/* We don't want to pick it up - so put it back in there */
copy_msgbuf->cursor--;
}
/* If we wanted to pick it up, it's already done */
break;
}
}
/*
* These functions do apply some data conversion
*/
/*
* CopySendInt32 sends an int32 in network byte order
*/
static void
CopySendInt32(int32 val)
{
uint32 buf;
buf = htonl((uint32) val);
CopySendData(&buf, sizeof(buf));
}
/*
* CopyGetInt32 reads an int32 that appears in network byte order
*/
static int32
CopyGetInt32(void)
{
uint32 buf;
CopyGetData(&buf, sizeof(buf));
return (int32) ntohl(buf);
}
/*
* CopySendInt16 sends an int16 in network byte order
*/
static void
CopySendInt16(int16 val)
{
uint16 buf;
buf = htons((uint16) val);
CopySendData(&buf, sizeof(buf));
}
/*
* CopyGetInt16 reads an int16 that appears in network byte order
*/
static int16
CopyGetInt16(void)
{
uint16 buf;
CopyGetData(&buf, sizeof(buf));
return (int16) ntohs(buf);
}
/*
* DoCopy executes the SQL COPY statement.
*
* Either unload or reload contents of table <relation>, depending on <from>.
* (<from> = TRUE means we are inserting into the table.)
*
* If <pipe> is false, transfer is between the table and the file named
* <filename>. Otherwise, transfer is between the table and our regular
* input/output stream. The latter could be either stdin/stdout or a
* socket, depending on whether we're running under Postmaster control.
*
* Iff <binary>, unload or reload in the binary format, as opposed to the
* more wasteful but more robust and portable text format.
*
* Iff <oids>, unload or reload the format that includes OID information.
* On input, we accept OIDs whether or not the table has an OID column,
* but silently drop them if it does not. On output, we report an error
* if the user asks for OIDs in a table that has none (not providing an
* OID column might seem friendlier, but could seriously confuse programs).
*
* If in the text format, delimit columns with delimiter <delim> and print
* NULL values as <null_print>.
*
* When loading in the text format from an input stream (as opposed to
* a file), recognize a "." on a line by itself as EOF. Also recognize
* a stream EOF. When unloading in the text format to an output stream,
* write a "." on a line by itself at the end of the data.
*
* Do not allow a Postgres user without superuser privilege to read from
* or write to a file.
*
* Do not allow the copy if user doesn't have proper permission to access
* the table.
*/
void
DoCopy(const CopyStmt *stmt)
{
RangeVar *relation = stmt->relation;
char *filename = stmt->filename;
bool is_from = stmt->is_from;
bool pipe = (stmt->filename == NULL);
List *option;
List *attnamelist = stmt->attlist;
List *attnumlist;
bool binary = false;
bool oids = false;
char *delim = NULL;
char *null_print = NULL;
Relation rel;
AclMode required_access = (is_from ? ACL_INSERT : ACL_SELECT);
AclResult aclresult;
/* Extract options from the statement node tree */
foreach(option, stmt->options)
{
DefElem *defel = (DefElem *) lfirst(option);
/* XXX: Should we bother checking for doubled options? */
if (strcmp(defel->defname, "binary") == 0)
{
if (binary)
elog(ERROR, "COPY: BINARY option appears more than once");
binary = intVal(defel->arg);
}
else if (strcmp(defel->defname, "oids") == 0)
{
if (oids)
elog(ERROR, "COPY: OIDS option appears more than once");
oids = intVal(defel->arg);
}
else if (strcmp(defel->defname, "delimiter") == 0)
{
if (delim)
elog(ERROR, "COPY: DELIMITER string may only be defined once in query");
delim = strVal(defel->arg);
}
else if (strcmp(defel->defname, "null") == 0)
{
if (null_print)
elog(ERROR, "COPY: NULL representation may only be defined once in query");
null_print = strVal(defel->arg);
}
else
elog(ERROR, "COPY: option \"%s\" not recognized",
defel->defname);
}
if (binary && delim)
elog(ERROR, "You can not specify the DELIMITER in BINARY mode.");
if (binary && null_print)
elog(ERROR, "You can not specify NULL in BINARY mode.");
/* Set defaults */
if (!delim)
delim = "\t";
if (!null_print)
null_print = "\\N";
/*
* Open and lock the relation, using the appropriate lock type.
*/
rel = heap_openrv(relation, (is_from ? RowExclusiveLock : AccessShareLock));
/* check read-only transaction */
if (XactReadOnly && !is_from && !isTempNamespace(RelationGetNamespace(rel)))
elog(ERROR, "transaction is read-only");
/* Check permissions. */
aclresult = pg_class_aclcheck(RelationGetRelid(rel), GetUserId(),
required_access);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, RelationGetRelationName(rel));
if (!pipe && !superuser())
elog(ERROR, "You must have Postgres superuser privilege to do a COPY "
"directly to or from a file. Anyone can COPY to stdout or "
"from stdin. Psql's \\copy command also works for anyone.");
/*
* Presently, only single-character delimiter strings are supported.
*/
if (strlen(delim) != 1)
elog(ERROR, "COPY delimiter must be a single character");
/*
* Don't allow COPY w/ OIDs to or from a table without them
*/
if (oids && !rel->rd_rel->relhasoids)
elog(ERROR, "COPY: table \"%s\" does not have OIDs",
RelationGetRelationName(rel));
/*
* Generate or convert list of attributes to process
*/
attnumlist = CopyGetAttnums(rel, attnamelist);
/*
* Set up variables to avoid per-attribute overhead.
*/
initStringInfo(&attribute_buf);
client_encoding = pg_get_client_encoding();
server_encoding = GetDatabaseEncoding();
copy_dest = COPY_FILE; /* default */
copy_file = NULL;
copy_msgbuf = NULL;
fe_eof = false;
if (is_from)
{ /* copy from file to database */
if (rel->rd_rel->relkind != RELKIND_RELATION)
{
if (rel->rd_rel->relkind == RELKIND_VIEW)
elog(ERROR, "You cannot copy view %s",
RelationGetRelationName(rel));
else if (rel->rd_rel->relkind == RELKIND_SEQUENCE)
elog(ERROR, "You cannot change sequence relation %s",
RelationGetRelationName(rel));
else
elog(ERROR, "You cannot copy object %s",
RelationGetRelationName(rel));
}
if (pipe)
{
if (IsUnderPostmaster)
ReceiveCopyBegin(binary, length(attnumlist));
else
copy_file = stdin;
}
else
{
struct stat st;
copy_file = AllocateFile(filename, PG_BINARY_R);
if (copy_file == NULL)
#ifndef WIN32
elog(ERROR, "COPY command, running in backend with "
"effective uid %d, could not open file '%s' for "
"reading. Errno = %s (%d).",
(int) geteuid(), filename, strerror(errno), errno);
#else
elog(ERROR, "COPY command, running in backend, "
"could not open file '%s' for "
"reading. Errno = %s (%d).",
filename, strerror(errno), errno);
#endif
fstat(fileno(copy_file), &st);
if (S_ISDIR(st.st_mode))
{
FreeFile(copy_file);
elog(ERROR, "COPY: %s is a directory", filename);
}
}
CopyFrom(rel, attnumlist, binary, oids, delim, null_print);
}
else
{ /* copy from database to file */
if (rel->rd_rel->relkind != RELKIND_RELATION)
{
if (rel->rd_rel->relkind == RELKIND_VIEW)
elog(ERROR, "You cannot copy view %s",
RelationGetRelationName(rel));
else if (rel->rd_rel->relkind == RELKIND_SEQUENCE)
elog(ERROR, "You cannot copy sequence %s",
RelationGetRelationName(rel));
else
elog(ERROR, "You cannot copy object %s",
RelationGetRelationName(rel));
}
if (pipe)
{
if (IsUnderPostmaster)
SendCopyBegin(binary, length(attnumlist));
else
copy_file = stdout;
}
else
{
mode_t oumask; /* Pre-existing umask value */
struct stat st;
/*
* Prevent write to relative path ... too easy to shoot
* oneself in the foot by overwriting a database file ...
*/
if (!is_absolute_path(filename))
elog(ERROR, "Relative path not allowed for server side"
" COPY command");
oumask = umask((mode_t) 022);
copy_file = AllocateFile(filename, PG_BINARY_W);
umask(oumask);
if (copy_file == NULL)
#ifndef WIN32
elog(ERROR, "COPY command, running in backend with "
"effective uid %d, could not open file '%s' for "
"writing. Errno = %s (%d).",
(int) geteuid(), filename, strerror(errno), errno);
#else
elog(ERROR, "COPY command, running in backend, "
"could not open file '%s' for "
"writing. Errno = %s (%d).",
filename, strerror(errno), errno);
#endif
fstat(fileno(copy_file), &st);
if (S_ISDIR(st.st_mode))
{
FreeFile(copy_file);
elog(ERROR, "COPY: %s is a directory", filename);
}
}
CopyTo(rel, attnumlist, binary, oids, delim, null_print);
}
if (!pipe)
FreeFile(copy_file);
else if (IsUnderPostmaster && !is_from)
SendCopyEnd(binary);
pfree(attribute_buf.data);
/*
* Close the relation. If reading, we can release the AccessShareLock
* we got; if writing, we should hold the lock until end of
* transaction to ensure that updates will be committed before lock is
* released.
*/
heap_close(rel, (is_from ? NoLock : AccessShareLock));
}
/*
* Copy from relation TO file.
*/
static void
CopyTo(Relation rel, List *attnumlist, bool binary, bool oids,
char *delim, char *null_print)
{
HeapTuple tuple;
TupleDesc tupDesc;
HeapScanDesc scandesc;
int num_phys_attrs;
int attr_count;
Form_pg_attribute *attr;
FmgrInfo *out_functions;
Oid *elements;
bool *isvarlena;
char *string;
Snapshot mySnapshot;
List *cur;
MemoryContext oldcontext;
MemoryContext mycontext;
tupDesc = rel->rd_att;
attr = tupDesc->attrs;
num_phys_attrs = tupDesc->natts;
attr_count = length(attnumlist);
/*
* Get info about the columns we need to process.
*
* +1's here are to avoid palloc(0) in a zero-column table.
*/
out_functions = (FmgrInfo *) palloc((num_phys_attrs + 1) * sizeof(FmgrInfo));
elements = (Oid *) palloc((num_phys_attrs + 1) * sizeof(Oid));
isvarlena = (bool *) palloc((num_phys_attrs + 1) * sizeof(bool));
foreach(cur, attnumlist)
{
int attnum = lfirsti(cur);
Oid out_func_oid;
if (binary)
getTypeBinaryOutputInfo(attr[attnum - 1]->atttypid,
&out_func_oid, &elements[attnum - 1],
&isvarlena[attnum - 1]);
else
getTypeOutputInfo(attr[attnum - 1]->atttypid,
&out_func_oid, &elements[attnum - 1],
&isvarlena[attnum - 1]);
fmgr_info(out_func_oid, &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 datatype output routines, and should be faster than retail
* pfree's anyway. (We don't need a whole econtext as CopyFrom does.)
*/
mycontext = AllocSetContextCreate(CurrentMemoryContext,
"COPY TO",
ALLOCSET_DEFAULT_MINSIZE,
ALLOCSET_DEFAULT_INITSIZE,
ALLOCSET_DEFAULT_MAXSIZE);
if (binary)
{
/* Generate header for a binary copy */
int32 tmp;
/* Signature */
CopySendData((char *) BinarySignature, 11);
/* Flags field */
tmp = 0;
if (oids)
tmp |= (1 << 16);
CopySendInt32(tmp);
/* No header extension */
tmp = 0;
CopySendInt32(tmp);
}
mySnapshot = CopyQuerySnapshot();
scandesc = heap_beginscan(rel, mySnapshot, 0, NULL);
while ((tuple = heap_getnext(scandesc, ForwardScanDirection)) != NULL)
{
bool need_delim = false;
CHECK_FOR_INTERRUPTS();
MemoryContextReset(mycontext);
oldcontext = MemoryContextSwitchTo(mycontext);
if (binary)
{
/* Binary per-tuple header */
CopySendInt16(attr_count);
/* Send OID if wanted --- note attr_count doesn't include it */
if (oids)
{
Oid oid = HeapTupleGetOid(tuple);
/* Hack --- assume Oid is same size as int32 */
CopySendInt32(sizeof(int32));
CopySendInt32(oid);
}
}
else
{
/* Text format has no per-tuple header, but send OID if wanted */
if (oids)
{
string = DatumGetCString(DirectFunctionCall1(oidout,
ObjectIdGetDatum(HeapTupleGetOid(tuple))));
CopySendString(string);
need_delim = true;
}
}
foreach(cur, attnumlist)
{
int attnum = lfirsti(cur);
Datum value;
bool isnull;
value = heap_getattr(tuple, attnum, tupDesc, &isnull);
if (!binary)
{
if (need_delim)
CopySendChar(delim[0]);
need_delim = true;
}
if (isnull)
{
if (!binary)
CopySendString(null_print); /* null indicator */
else
CopySendInt32(-1); /* null marker */
}
else
{
if (!binary)
{
string = DatumGetCString(FunctionCall3(&out_functions[attnum - 1],
value,
ObjectIdGetDatum(elements[attnum - 1]),
Int32GetDatum(attr[attnum - 1]->atttypmod)));
CopyAttributeOut(string, delim);
}
else
{
bytea *outputbytes;
outputbytes = DatumGetByteaP(FunctionCall2(&out_functions[attnum - 1],
value,
ObjectIdGetDatum(elements[attnum - 1])));
/* We assume the result will not have been toasted */
CopySendInt32(VARSIZE(outputbytes) - VARHDRSZ);
CopySendData(VARDATA(outputbytes),
VARSIZE(outputbytes) - VARHDRSZ);
}
}
}
CopySendEndOfRow(binary);
MemoryContextSwitchTo(oldcontext);
}
heap_endscan(scandesc);
if (binary)
{
/* Generate trailer for a binary copy */
CopySendInt16(-1);
}
MemoryContextDelete(mycontext);
pfree(out_functions);
pfree(elements);
pfree(isvarlena);
}
/*
* error context callback for COPY FROM
*/
static void
copy_in_error_callback(void *arg)
{
errcontext("COPY FROM, line %d", copy_lineno);
}
/*
* Copy FROM file to relation.
*/
static void
CopyFrom(Relation rel, List *attnumlist, bool binary, bool oids,
char *delim, char *null_print)
{
HeapTuple tuple;
TupleDesc tupDesc;
Form_pg_attribute *attr;
AttrNumber num_phys_attrs,
attr_count,
num_defaults;
FmgrInfo *in_functions;
FmgrInfo oid_in_function;
Oid *elements;
Oid oid_in_element;
ExprState **constraintexprs;
bool hasConstraints = false;
int i;
List *cur;
Oid in_func_oid;
Datum *values;
char *nulls;
bool done = false;
bool isnull;
ResultRelInfo *resultRelInfo;
EState *estate = CreateExecutorState(); /* for ExecConstraints() */
TupleTable tupleTable;
TupleTableSlot *slot;
bool file_has_oids;
int *defmap;
ExprState **defexprs; /* array of default att expressions */
ExprContext *econtext; /* used for ExecEvalExpr for default atts */
MemoryContext oldcontext = CurrentMemoryContext;
ErrorContextCallback errcontext;
tupDesc = RelationGetDescr(rel);
attr = tupDesc->attrs;
num_phys_attrs = tupDesc->natts;
attr_count = length(attnumlist);
num_defaults = 0;
/*
* We need a ResultRelInfo so we can use the regular executor's
* index-entry-making machinery. (There used to be a huge amount of
* code here that basically duplicated execUtils.c ...)
*/
resultRelInfo = makeNode(ResultRelInfo);
resultRelInfo->ri_RangeTableIndex = 1; /* dummy */
resultRelInfo->ri_RelationDesc = rel;
resultRelInfo->ri_TrigDesc = CopyTriggerDesc(rel->trigdesc);
ExecOpenIndices(resultRelInfo);
estate->es_result_relations = resultRelInfo;
estate->es_num_result_relations = 1;
estate->es_result_relation_info = resultRelInfo;
/* Set up a dummy tuple table too */
tupleTable = ExecCreateTupleTable(1);
slot = ExecAllocTableSlot(tupleTable);
ExecSetSlotDescriptor(slot, tupDesc, false);
econtext = GetPerTupleExprContext(estate);
/*
* Pick up the required catalog information for each attribute in the
* relation, including the input function, the element type (to pass
* to the input function), and info about defaults and constraints.
* (Which input function we use depends on text/binary format choice.)
* +1's here are to avoid palloc(0) in a zero-column table.
*/
in_functions = (FmgrInfo *) palloc((num_phys_attrs + 1) * sizeof(FmgrInfo));
elements = (Oid *) palloc((num_phys_attrs + 1) * sizeof(Oid));
defmap = (int *) palloc((num_phys_attrs + 1) * sizeof(int));
defexprs = (ExprState **) palloc((num_phys_attrs + 1) * sizeof(ExprState *));
constraintexprs = (ExprState **) palloc0((num_phys_attrs + 1) * sizeof(ExprState *));
for (i = 0; i < num_phys_attrs; i++)
{
/* We don't need info for dropped attributes */
if (attr[i]->attisdropped)
continue;
/* Fetch the input function and typelem info */
if (binary)
getTypeBinaryInputInfo(attr[i]->atttypid,
&in_func_oid, &elements[i]);
else
getTypeInputInfo(attr[i]->atttypid,
&in_func_oid, &elements[i]);
fmgr_info(in_func_oid, &in_functions[i]);
/* Get default info if needed */
if (!intMember(i + 1, attnumlist))
{
/* attribute is NOT to be copied from input */
/* use default value if one exists */
Node *defexpr = build_column_default(rel, i + 1);
if (defexpr != NULL)
{
defexprs[num_defaults] = ExecPrepareExpr((Expr *) defexpr,
estate);
defmap[num_defaults] = i;
num_defaults++;
}
}
/* If it's a domain type, set up to check domain constraints */
if (get_typtype(attr[i]->atttypid) == 'd')
{
Param *prm;
Node *node;
/*
* Easiest way to do this is to use parse_coerce.c to set up
* an expression that checks the constraints. (At present,
* the expression might contain a length-coercion-function call
* and/or CoerceToDomain nodes.) The bottom of the expression
* is a Param node so that we can fill in the actual datum during
* the data input loop.
*/
prm = makeNode(Param);
prm->paramkind = PARAM_EXEC;
prm->paramid = 0;
prm->paramtype = getBaseType(attr[i]->atttypid);
node = coerce_to_domain((Node *) prm,
prm->paramtype,
attr[i]->atttypid,
COERCE_IMPLICIT_CAST);
constraintexprs[i] = ExecPrepareExpr((Expr *) node,
estate);
hasConstraints = true;
}
}
/*
* Check BEFORE STATEMENT insertion triggers. It's debateable
* whether we should do this for COPY, since it's not really an
* "INSERT" statement as such. However, executing these triggers
* maintains consistency with the EACH ROW triggers that we already
* fire on COPY.
*/
ExecBSInsertTriggers(estate, resultRelInfo);
if (!binary)
{
file_has_oids = oids; /* must rely on user to tell us this... */
}
else
{
/* Read and verify binary header */
char readSig[11];
int32 tmp;
/* Signature */
CopyGetData(readSig, 11);
if (CopyGetEof() || memcmp(readSig, BinarySignature, 11) != 0)
elog(ERROR, "COPY BINARY: file signature not recognized");
/* Flags field */
tmp = CopyGetInt32();
if (CopyGetEof())
elog(ERROR, "COPY BINARY: bogus file header (missing flags)");
file_has_oids = (tmp & (1 << 16)) != 0;
tmp &= ~(1 << 16);
if ((tmp >> 16) != 0)
elog(ERROR, "COPY BINARY: unrecognized critical flags in header");
/* Header extension length */
tmp = CopyGetInt32();
if (CopyGetEof() || tmp < 0)
elog(ERROR, "COPY BINARY: bogus file header (missing length)");
/* Skip extension header, if present */
while (tmp-- > 0)
{
CopyGetData(readSig, 1);
if (CopyGetEof())
elog(ERROR, "COPY BINARY: bogus file header (wrong length)");
}
}
if (file_has_oids && binary)
{
getTypeBinaryInputInfo(OIDOID,
&in_func_oid, &oid_in_element);
fmgr_info(in_func_oid, &oid_in_function);
}
values = (Datum *) palloc((num_phys_attrs + 1) * sizeof(Datum));
nulls = (char *) palloc((num_phys_attrs + 1) * sizeof(char));
/* Make room for a PARAM_EXEC value for domain constraint checks */
if (hasConstraints)
econtext->ecxt_param_exec_vals = (ParamExecData *)
palloc0(sizeof(ParamExecData));
/* Initialize static variables */
fe_eof = false;
eol_type = EOL_UNKNOWN;
copy_lineno = 0;
/* Set up callback to identify error line number */
errcontext.callback = copy_in_error_callback;
errcontext.arg = NULL;
errcontext.previous = error_context_stack;
error_context_stack = &errcontext;
while (!done)
{
bool skip_tuple;
Oid loaded_oid = InvalidOid;
CHECK_FOR_INTERRUPTS();
copy_lineno++;
/* Reset the per-tuple exprcontext */
ResetPerTupleExprContext(estate);
/* Switch into its memory context */
MemoryContextSwitchTo(GetPerTupleMemoryContext(estate));
/* Initialize all values for row to NULL */
MemSet(values, 0, num_phys_attrs * sizeof(Datum));
MemSet(nulls, 'n', num_phys_attrs * sizeof(char));
if (!binary)
{
CopyReadResult result = NORMAL_ATTR;
char *string;
if (file_has_oids)
{
string = CopyReadAttribute(delim, &result);
if (result == END_OF_FILE && *string == '\0')
{
/* EOF at start of line: all is well */
done = true;
break;
}
if (strcmp(string, null_print) == 0)
elog(ERROR, "NULL Oid");
else
{
loaded_oid = DatumGetObjectId(DirectFunctionCall1(oidin,
CStringGetDatum(string)));
if (loaded_oid == InvalidOid)
elog(ERROR, "Invalid Oid");
}
}
/*
* Loop to read the user attributes on the line.
*/
foreach(cur, attnumlist)
{
int attnum = lfirsti(cur);
int m = attnum - 1;
/*
* If prior attr on this line was ended by newline or EOF,
* complain.
*/
if (result != NORMAL_ATTR)
elog(ERROR, "Missing data for column \"%s\"",
NameStr(attr[m]->attname));
string = CopyReadAttribute(delim, &result);
if (result == END_OF_FILE && *string == '\0' &&
cur == attnumlist && !file_has_oids)
{
/* EOF at start of line: all is well */
done = true;
break; /* out of per-attr loop */
}
if (strcmp(string, null_print) == 0)
{
/* we read an SQL NULL, no need to do anything */
}
else
{
values[m] = FunctionCall3(&in_functions[m],
CStringGetDatum(string),
ObjectIdGetDatum(elements[m]),
Int32GetDatum(attr[m]->atttypmod));
nulls[m] = ' ';
}
}
if (done)
break; /* out of per-row loop */
/*
* Complain if there are more fields on the input line.
*
* Special case: if we're reading a zero-column table, we
* won't yet have called CopyReadAttribute() at all; so do that
* and check we have an empty line. Fortunately we can keep that
* silly corner case out of the main line of execution.
*/
if (result == NORMAL_ATTR)
{
if (attnumlist == NIL && !file_has_oids)
{
string = CopyReadAttribute(delim, &result);
if (result == NORMAL_ATTR || *string != '\0')
elog(ERROR, "Extra data after last expected column");
if (result == END_OF_FILE)
{
/* EOF at start of line: all is well */
done = true;
break;
}
}
else
elog(ERROR, "Extra data after last expected column");
}
/*
* If we got some data on the line, but it was ended by EOF,
* process the line normally but set flag to exit the loop
* when we return to the top.
*/
if (result == END_OF_FILE)
done = true;
}
else
{
/* binary */
int16 fld_count;
fld_count = CopyGetInt16();
if (CopyGetEof() || fld_count == -1)
{
done = true;
break;
}
if (fld_count != attr_count)
elog(ERROR, "COPY BINARY: tuple field count is %d, expected %d",
(int) fld_count, attr_count);
if (file_has_oids)
{
loaded_oid =
DatumGetObjectId(CopyReadBinaryAttribute(0,
&oid_in_function,
oid_in_element,
&isnull));
if (isnull || loaded_oid == InvalidOid)
elog(ERROR, "COPY BINARY: Invalid Oid");
}
i = 0;
foreach(cur, attnumlist)
{
int attnum = lfirsti(cur);
int m = attnum - 1;
i++;
values[m] = CopyReadBinaryAttribute(i,
&in_functions[m],
elements[m],
&isnull);
nulls[m] = isnull ? 'n' : ' ';
}
}
/*
* Now compute and insert any defaults available for the columns
* not provided by the input data. Anything not processed here or
* above will remain NULL.
*/
for (i = 0; i < num_defaults; i++)
{
values[defmap[i]] = ExecEvalExpr(defexprs[i], econtext,
&isnull, NULL);
if (!isnull)
nulls[defmap[i]] = ' ';
}
/*
* Next apply any domain constraints
*/
if (hasConstraints)
{
ParamExecData *prmdata = &econtext->ecxt_param_exec_vals[0];
for (i = 0; i < num_phys_attrs; i++)
{
ExprState *exprstate = constraintexprs[i];
if (exprstate == NULL)
continue; /* no constraint for this attr */
/* Insert current row's value into the Param value */
prmdata->value = values[i];
prmdata->isnull = (nulls[i] == 'n');
/*
* Execute the constraint expression. Allow the expression
* to replace the value (consider e.g. a timestamp precision
* restriction).
*/
values[i] = ExecEvalExpr(exprstate, econtext,
&isnull, NULL);
nulls[i] = isnull ? 'n' : ' ';
}
}
/*
* And now we can form the input tuple.
*/
tuple = heap_formtuple(tupDesc, values, nulls);
if (oids && file_has_oids)
HeapTupleSetOid(tuple, loaded_oid);
/*
* Triggers and stuff need to be invoked in query context.
*/
MemoryContextSwitchTo(oldcontext);
skip_tuple = false;
/* BEFORE ROW INSERT Triggers */
if (resultRelInfo->ri_TrigDesc &&
resultRelInfo->ri_TrigDesc->n_before_row[TRIGGER_EVENT_INSERT] > 0)
{
HeapTuple newtuple;
newtuple = ExecBRInsertTriggers(estate, resultRelInfo, tuple);
if (newtuple == NULL) /* "do nothing" */
skip_tuple = true;
else if (newtuple != tuple) /* modified by Trigger(s) */
{
heap_freetuple(tuple);
tuple = newtuple;
}
}
if (!skip_tuple)
{
/* Place tuple in tuple slot */
ExecStoreTuple(tuple, slot, InvalidBuffer, false);
/*
* Check the constraints of the tuple
*/
if (rel->rd_att->constr)
ExecConstraints("CopyFrom", resultRelInfo, slot, estate);
/*
* OK, store the tuple and create index entries for it
*/
simple_heap_insert(rel, tuple);
if (resultRelInfo->ri_NumIndices > 0)
ExecInsertIndexTuples(slot, &(tuple->t_self), estate, false);
/* AFTER ROW INSERT Triggers */
ExecARInsertTriggers(estate, resultRelInfo, tuple);
}
}
/*
* Done, clean up
*/
error_context_stack = errcontext.previous;
MemoryContextSwitchTo(oldcontext);
/*
* Execute AFTER STATEMENT insertion triggers
*/
ExecASInsertTriggers(estate, resultRelInfo);
pfree(values);
pfree(nulls);
if (!binary)
{
pfree(in_functions);
pfree(elements);
}
ExecDropTupleTable(tupleTable, true);
ExecCloseIndices(resultRelInfo);
FreeExecutorState(estate);
}
/*
* Read the value of a single attribute.
*
* *result is set to indicate what terminated the read:
* NORMAL_ATTR: column delimiter
* END_OF_LINE: newline
* END_OF_FILE: EOF indicator
* In all cases, the string read up to the terminator is returned.
*
* Note: This function does not care about SQL NULL values -- it
* is the caller's responsibility to check if the returned string
* matches what the user specified for the SQL NULL value.
*
* delim is the column delimiter string.
*/
static char *
CopyReadAttribute(const char *delim, CopyReadResult *result)
{
int c;
int delimc = (unsigned char) delim[0];
int mblen;
unsigned char s[2];
char *cvt;
int j;
s[1] = 0;
/* reset attribute_buf to empty */
attribute_buf.len = 0;
attribute_buf.data[0] = '\0';
/* set default status */
*result = NORMAL_ATTR;
for (;;)
{
c = CopyGetChar();
if (c == EOF)
{
*result = END_OF_FILE;
goto copy_eof;
}
if (c == '\r')
{
if (eol_type == EOL_NL)
elog(ERROR, "CopyReadAttribute: Literal carriage return data value\n"
"found in input that has newline termination; use \\r");
/* Check for \r\n on first line, _and_ handle \r\n. */
if (copy_lineno == 1 || eol_type == EOL_CRNL)
{
int c2 = CopyPeekChar();
if (c2 == '\n')
{
CopyDonePeek(c2, true); /* eat newline */
eol_type = EOL_CRNL;
}
else
{
/* found \r, but no \n */
if (eol_type == EOL_CRNL)
elog(ERROR, "CopyReadAttribute: Literal carriage return data value\n"
"found in input that has carriage return/newline termination; use \\r");
/* if we got here, it is the first line and we didn't get \n, so put it back */
CopyDonePeek(c2, false);
eol_type = EOL_CR;
}
}
*result = END_OF_LINE;
break;
}
if (c == '\n')
{
if (eol_type == EOL_CRNL)
elog(ERROR, "CopyReadAttribute: Literal newline data value found in input\n"
"that has carriage return/newline termination; use \\n");
if (eol_type == EOL_CR)
elog(ERROR, "CopyReadAttribute: Literal newline data value found in input\n"
"that has carriage return termination; use \\n");
eol_type = EOL_NL;
*result = END_OF_LINE;
break;
}
if (c == delimc)
break;
if (c == '\\')
{
c = CopyGetChar();
if (c == EOF)
{
*result = END_OF_FILE;
goto copy_eof;
}
switch (c)
{
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
{
int val;
val = OCTVALUE(c);
c = CopyPeekChar();
if (ISOCTAL(c))
{
val = (val << 3) + OCTVALUE(c);
CopyDonePeek(c, true /* pick up */ );
c = CopyPeekChar();
if (ISOCTAL(c))
{
val = (val << 3) + OCTVALUE(c);
CopyDonePeek(c, true /* pick up */ );
}
else
{
if (c == EOF)
{
*result = END_OF_FILE;
goto copy_eof;
}
CopyDonePeek(c, false /* put back */ );
}
}
else
{
if (c == EOF)
{
*result = END_OF_FILE;
goto copy_eof;
}
CopyDonePeek(c, false /* put back */ );
}
c = val & 0377;
}
break;
/*
* This is a special hack to parse `\N' as
* <backslash-N> rather then just 'N' to provide
* compatibility with the default NULL output. -- pe
*/
case 'N':
appendStringInfoCharMacro(&attribute_buf, '\\');
c = 'N';
break;
case 'b':
c = '\b';
break;
case 'f':
c = '\f';
break;
case 'n':
c = '\n';
break;
case 'r':
c = '\r';
break;
case 't':
c = '\t';
break;
case 'v':
c = '\v';
break;
case '.':
if (eol_type == EOL_CRNL)
{
c = CopyGetChar();
if (c == '\n')
elog(ERROR, "CopyReadAttribute: end-of-copy termination does not match previous input");
if (c != '\r')
elog(ERROR, "CopyReadAttribute: end-of-copy marker corrupt");
}
c = CopyGetChar();
if (c != '\r' && c != '\n')
elog(ERROR, "CopyReadAttribute: end-of-copy marker corrupt");
if (((eol_type == EOL_NL || eol_type == EOL_CRNL) && c != '\n') ||
(eol_type == EOL_CR && c != '\r'))
elog(ERROR, "CopyReadAttribute: end-of-copy termination does not match previous input");
/*
* In protocol version 3, we should ignore anything after
* \. up to the protocol end of copy data. (XXX maybe
* better not to treat \. as special?)
*/
if (copy_dest == COPY_NEW_FE)
{
while (c != EOF)
{
c = CopyGetChar();
}
}
*result = END_OF_FILE;
goto copy_eof;
}
}
appendStringInfoCharMacro(&attribute_buf, c);
/* XXX shouldn't this be done even when encoding is the same? */
if (client_encoding != server_encoding)
{
/* get additional bytes of the char, if any */
s[0] = c;
mblen = pg_encoding_mblen(client_encoding, s);
for (j = 1; j < mblen; j++)
{
c = CopyGetChar();
if (c == EOF)
{
*result = END_OF_FILE;
goto copy_eof;
}
appendStringInfoCharMacro(&attribute_buf, c);
}
}
}
copy_eof:
if (client_encoding != server_encoding)
{
cvt = (char *) pg_client_to_server((unsigned char *) attribute_buf.data,
attribute_buf.len);
if (cvt != attribute_buf.data)
{
/* transfer converted data back to attribute_buf */
attribute_buf.len = 0;
attribute_buf.data[0] = '\0';
appendBinaryStringInfo(&attribute_buf, cvt, strlen(cvt));
}
}
return attribute_buf.data;
}
/*
* Read a binary attribute
*/
static Datum
CopyReadBinaryAttribute(int column_no, FmgrInfo *flinfo, Oid typelem,
bool *isnull)
{
int32 fld_size;
Datum result;
fld_size = CopyGetInt32();
if (CopyGetEof())
elog(ERROR, "COPY BINARY: unexpected EOF");
if (fld_size == -1)
{
*isnull = true;
return (Datum) 0;
}
if (fld_size < 0)
elog(ERROR, "COPY BINARY: bogus size for field %d", column_no);
/* reset attribute_buf to empty, and load raw data in it */
attribute_buf.len = 0;
attribute_buf.data[0] = '\0';
attribute_buf.cursor = 0;
enlargeStringInfo(&attribute_buf, fld_size);
CopyGetData(attribute_buf.data, fld_size);
if (CopyGetEof())
elog(ERROR, "COPY BINARY: unexpected EOF");
attribute_buf.len = fld_size;
attribute_buf.data[fld_size] = '\0';
/* Call the column type's binary input converter */
result = FunctionCall2(flinfo,
PointerGetDatum(&attribute_buf),
ObjectIdGetDatum(typelem));
/* Trouble if it didn't eat the whole buffer */
if (attribute_buf.cursor != attribute_buf.len)
elog(ERROR, "Improper binary format in field %d", column_no);
*isnull = false;
return result;
}
/*
* Send text representation of one attribute, with conversion and escaping
*/
static void
CopyAttributeOut(char *server_string, char *delim)
{
char *string;
char c;
char delimc = delim[0];
bool same_encoding;
int mblen;
int i;
same_encoding = (server_encoding == client_encoding);
if (!same_encoding)
string = (char *) pg_server_to_client((unsigned char *) server_string,
strlen(server_string));
else
string = server_string;
for (; (c = *string) != '\0'; string += mblen)
{
mblen = 1;
switch (c)
{
case '\b':
CopySendString("\\b");
break;
case '\f':
CopySendString("\\f");
break;
case '\n':
CopySendString("\\n");
break;
case '\r':
CopySendString("\\r");
break;
case '\t':
CopySendString("\\t");
break;
case '\v':
CopySendString("\\v");
break;
case '\\':
CopySendString("\\\\");
break;
default:
if (c == delimc)
CopySendChar('\\');
CopySendChar(c);
/*
* We can skip pg_encoding_mblen() overhead when encoding
* is same, because in valid backend encodings, extra
* bytes of a multibyte character never look like ASCII.
*/
if (!same_encoding)
{
/* send additional bytes of the char, if any */
mblen = pg_encoding_mblen(client_encoding, string);
for (i = 1; i < mblen; i++)
CopySendChar(string[i]);
}
break;
}
}
}
/*
* CopyGetAttnums - build an integer list of attnums to be copied
*
* The input attnamelist is either the user-specified column list,
* or NIL if there was none (in which case we want all the non-dropped
* columns).
*/
static List *
CopyGetAttnums(Relation rel, List *attnamelist)
{
List *attnums = NIL;
if (attnamelist == NIL)
{
/* Generate default column list */
TupleDesc tupDesc = RelationGetDescr(rel);
Form_pg_attribute *attr = tupDesc->attrs;
int attr_count = tupDesc->natts;
int i;
for (i = 0; i < attr_count; i++)
{
if (attr[i]->attisdropped)
continue;
attnums = lappendi(attnums, i + 1);
}
}
else
{
/* Validate the user-supplied list and extract attnums */
List *l;
foreach(l, attnamelist)
{
char *name = strVal(lfirst(l));
int attnum;
/* Lookup column name, elog on failure */
/* Note we disallow system columns here */
attnum = attnameAttNum(rel, name, false);
/* Check for duplicates */
if (intMember(attnum, attnums))
elog(ERROR, "Attribute \"%s\" specified more than once", name);
attnums = lappendi(attnums, attnum);
}
}
return attnums;
}