/*
* Like GetExtTableEntry(Oid), but returns NULL instead of throwing
* an error if no pg_exttable entry is found.
*/
ExtTableEntry*
GetExtTableEntryIfExists(Oid relid)
{
Relation pg_exttable_rel;
ScanKeyData skey;
SysScanDesc scan;
HeapTuple tuple;
ExtTableEntry *extentry;
Datum locations,
fmtcode,
fmtopts,
command,
rejectlimit,
rejectlimittype,
fmterrtbl,
encoding,
iswritable;
bool isNull;
bool locationNull = false;
pg_exttable_rel = heap_open(ExtTableRelationId, RowExclusiveLock);
ScanKeyInit(&skey,
Anum_pg_exttable_reloid,
BTEqualStrategyNumber, F_OIDEQ,
ObjectIdGetDatum(relid));
scan = systable_beginscan(pg_exttable_rel, ExtTableReloidIndexId, true,
SnapshotNow, 1, &skey);
tuple = systable_getnext(scan);
if (!HeapTupleIsValid(tuple))
{
systable_endscan(scan);
heap_close(pg_exttable_rel, RowExclusiveLock);
return NULL;
}
extentry = (ExtTableEntry *) palloc0(sizeof(ExtTableEntry));
/* get the location list */
locations = heap_getattr(tuple,
Anum_pg_exttable_location,
RelationGetDescr(pg_exttable_rel),
&isNull);
if (isNull)
{
Insist(false); /* location list is always populated (url or ON X) */
}
else
{
Datum *elems;
int nelems;
int i;
char* loc_str = NULL;
deconstruct_array(DatumGetArrayTypeP(locations),
TEXTOID, -1, false, 'i',
&elems, NULL, &nelems);
for (i = 0; i < nelems; i++)
{
loc_str = DatumGetCString(DirectFunctionCall1(textout, elems[i]));
/* append to a list of Value nodes, size nelems */
extentry->locations = lappend(extentry->locations, makeString(pstrdup(loc_str)));
}
if(loc_str && (IS_FILE_URI(loc_str) || IS_GPFDIST_URI(loc_str) || IS_GPFDISTS_URI(loc_str)))
extentry->isweb = false;
else
extentry->isweb = true;
}
/* get the execute command */
command = heap_getattr(tuple,
Anum_pg_exttable_command,
RelationGetDescr(pg_exttable_rel),
&isNull);
if(isNull)
{
if(locationNull)
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_OBJECT),
errmsg("got invalid pg_exttable tuple. location and command are both NULL")));
extentry->command = NULL;
}
else
{
extentry->command = DatumGetCString(DirectFunctionCall1(textout, command));
}
/* get the format code */
fmtcode = heap_getattr(tuple,
Anum_pg_exttable_fmttype,
RelationGetDescr(pg_exttable_rel),
&isNull);
Insist(!isNull);
extentry->fmtcode = DatumGetChar(fmtcode);
Insist(extentry->fmtcode == 'c' || extentry->fmtcode == 't'
|| extentry->fmtcode == 'b' || extentry->fmtcode == 'a'
|| extentry->fmtcode == 'p');
/* get the format options string */
fmtopts = heap_getattr(tuple,
Anum_pg_exttable_fmtopts,
RelationGetDescr(pg_exttable_rel),
&isNull);
Insist(!isNull);
extentry->fmtopts = DatumGetCString(DirectFunctionCall1(textout, fmtopts));
/* get the reject limit */
rejectlimit = heap_getattr(tuple,
Anum_pg_exttable_rejectlimit,
RelationGetDescr(pg_exttable_rel),
&isNull);
if(!isNull)
extentry->rejectlimit = DatumGetInt32(rejectlimit);
else
extentry->rejectlimit = -1; /* mark that no SREH requested */
/* get the reject limit type */
rejectlimittype = heap_getattr(tuple,
Anum_pg_exttable_rejectlimittype,
RelationGetDescr(pg_exttable_rel),
&isNull);
extentry->rejectlimittype = DatumGetChar(rejectlimittype);
if(!isNull)
Insist(extentry->rejectlimittype == 'r' || extentry->rejectlimittype == 'p');
else
extentry->rejectlimittype = -1;
/* get the error table oid */
fmterrtbl = heap_getattr(tuple,
Anum_pg_exttable_fmterrtbl,
RelationGetDescr(pg_exttable_rel),
&isNull);
if(isNull)
extentry->fmterrtbl = InvalidOid;
else
extentry->fmterrtbl = DatumGetObjectId(fmterrtbl);
/* get the table encoding */
encoding = heap_getattr(tuple,
Anum_pg_exttable_encoding,
RelationGetDescr(pg_exttable_rel),
&isNull);
Insist(!isNull);
extentry->encoding = DatumGetInt32(encoding);
Insist(PG_VALID_ENCODING(extentry->encoding));
/* get the table encoding */
iswritable = heap_getattr(tuple,
Anum_pg_exttable_writable,
RelationGetDescr(pg_exttable_rel),
&isNull);
Insist(!isNull);
extentry->iswritable = DatumGetBool(iswritable);
/* Finish up scan and close pg_exttable catalog. */
systable_endscan(scan);
heap_close(pg_exttable_rel, RowExclusiveLock);
return extentry;
}
/*
* ParseExternalTableUri
*
* This routines converts a string to a supported external
* table URI object. It is also used to validate the URI format.
*/
Uri *
ParseExternalTableUri(const char *uri_str)
{
Uri *uri = (Uri *) palloc0(sizeof(Uri));
char *start,
*end;
int protocol_len,
len;
uri->port = -1;
uri->hostname = NULL;
uri->path = NULL;
uri->customprotocol = NULL;
/*
* parse protocol
*/
if (IS_FILE_URI(uri_str))
{
uri->protocol = URI_FILE;
protocol_len = strlen(PROTOCOL_FILE);
}
else if (pg_strncasecmp(uri_str, PROTOCOL_FTP, strlen(PROTOCOL_FTP)) == 0)
{
uri->protocol = URI_FTP;
protocol_len = strlen(PROTOCOL_FTP);
}
else if (IS_HTTP_URI(uri_str))
{
uri->protocol = URI_HTTP;
protocol_len = strlen(PROTOCOL_HTTP);
}
else if (IS_GPFDIST_URI(uri_str))
{
uri->protocol = URI_GPFDIST;
protocol_len = strlen(PROTOCOL_GPFDIST);
}
else if (IS_GPFDISTS_URI(uri_str))
{
uri->protocol = URI_GPFDISTS;
protocol_len = strlen(PROTOCOL_GPFDISTS);
}
else /* not recognized. treat it as a custom protocol */
{
char *post_protocol = strstr(uri_str, "://");
if(!post_protocol)
{
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("invalid URI \'%s\' : undefined structure", uri_str),
errOmitLocation(true)));
}
else
{
protocol_len = post_protocol - uri_str;
uri->customprotocol = (char *) palloc (protocol_len + 1);
strncpy(uri->customprotocol, uri_str, protocol_len);
uri->customprotocol[protocol_len] = '\0';
uri->protocol = URI_CUSTOM;
return uri; /* we let the user parse it himself later on */
}
/* this is a non existing protocol */
protocol_len = 0; /* shut compiler up */
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("invalid URI \'%s\' : undefined protocol", uri_str),
errOmitLocation(true)));
}
/* make sure there is more to the uri string */
if (strlen(uri_str) <= protocol_len)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("invalid URI \'%s\' : missing host name and path", uri_str),
errOmitLocation(true)));
/*
* parse host name
*/
start = (char *) uri_str + protocol_len;
if (*start == '/') /* format "prot:///" ? (no hostname) */
{
/* the default is "localhost" */
const char *lh = "localhost";
len = strlen(lh);
uri->hostname = (char *) palloc(len + 1);
strncpy(uri->hostname, lh, len);
uri->hostname[len] = '\0';
end = start;
}
else
{
end = strchr(start, '/');
if (end == NULL)
{
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("invalid URI \'%s\' : missing host name or path", uri_str),
errOmitLocation(true)));
}
else
{
char *colon, *p;
len = end - start;
/*
* host
*/
uri->hostname = (char *) palloc(len + 1);
strncpy(uri->hostname, start, len);
uri->hostname[len] = '\0';
/*
* MPP-13617, if we have an ipv6 address in the URI hostname
* (e.g. [2620:0:170:610::11]:8080/path/data.txt ) then we
* we start our search for the :port after the closing ].
*/
p = strchr(uri->hostname, ']');
if (p)
{
colon = strchr(p, ':');
/*
* Eliminate the [ ] from the hostname.
* note we don't change the uri->hostname pointer because we pfree() it later
*/
*p = '\0';
for (p = strchr(uri->hostname, '['); p && *p; p++)
{
p[0] = p[1];
}
}
else
{
colon = strchr(uri->hostname, ':');
}
/*
* port
*/
if (colon)
{
int portlen = 0;
uri->port = atoi(colon + 1);
portlen = strlen(colon);
/* now truncate ":<port>" from hostname */
uri->hostname[len - portlen] = '\0';
*colon = 0;
}
else
{
uri->port = -1; /* no port was indicated. will use default if needed */
}
}
}
/*
* We continue from the trailing host '/' since the
* path is an absolute path. Our previous ending point
* is the beginning of the file path, until the end of
* the uri string.
*/
start = end;
len = strlen(start);
/* make sure there is more to the uri string */
if (len <= 1)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("invalid URI \'%s\' : missing path", uri_str),
errOmitLocation(true)));
uri->path = (char *) palloc(len + 1);
strcpy(uri->path, start);
uri->path[len] = '\0';
return uri;
}