/*
* GetDatabasePath - construct path to a database dir
*
* Result is a palloc'd string.
*
* XXX this must agree with relpath()!
*/
char *
GetDatabasePath(Oid dbNode, Oid spcNode)
{
int pathlen;
char *path;
int snprintfResult;
if (spcNode == GLOBALTABLESPACE_OID)
{
/* Shared system relations live in {datadir}/global */
Assert(dbNode == 0);
pathlen = 6 + 1;
path = (char *) palloc(pathlen);
// Using strncpy is error prone.
snprintfResult =
snprintf(path, pathlen, "global");
}
else if (spcNode == DEFAULTTABLESPACE_OID)
{
/* The default tablespace is {datadir}/base */
pathlen = 5 + OIDCHARS + 1;
path = (char *) palloc(pathlen);
snprintfResult =
snprintf(path, pathlen, "base/%u",
dbNode);
}
else
{
char *primary_path;
/* All other tablespaces are accessed via filespace locations */
GetFilespacePathForTablespace(
spcNode,
&primary_path);
/*
* We should develop an interface for the above that doesn't
* require reallocating to a slightly larger size...
*/
pathlen = strlen(primary_path)+1+OIDCHARS+1+OIDCHARS+1;
path = (char *) palloc(pathlen);
snprintfResult =
snprintf(path, pathlen, "%s/%u/%u",
primary_path, spcNode, dbNode);
/* Throw away the allocation we got from persistent layer */
pfree(primary_path);
}
Assert(snprintfResult >= 0);
Assert(snprintfResult < pathlen);
return path;
}
/*
* get_hdfs_location_from_filespace
*
* Get hdfs location from pg_filespace_entry
* The returned path needs to be pfreed by the caller.
*/
void get_hdfs_location_from_filespace(char** path)
{
Assert(NULL != path);
Oid dtsoid = get_database_dts(MyDatabaseId);
GetFilespacePathForTablespace(dtsoid, path);
Assert(NULL != *path);
Assert(strlen(*path) < FilespaceLocationBlankPaddedWithNullTermLen);
elog(DEBUG2, "found hdfs location is %s", *path);
}
void
CopyDatabasePath(char *target, int targetMaxLen, Oid dbNode, Oid spcNode)
{
int snprintfResult;
if (spcNode == GLOBALTABLESPACE_OID)
{
/* Shared system relations live in {datadir}/global */
Assert(dbNode == 0);
// Using strncpy is error prone.
snprintfResult =
snprintf(target, targetMaxLen, "global");
}
else if (spcNode == DEFAULTTABLESPACE_OID)
{
/* The default tablespace is {datadir}/base */
snprintfResult =
snprintf(target, targetMaxLen, "base/%u",
dbNode);
}
else
{
char *primary_path;
/* All other tablespaces are accessed via filespace locations */
GetFilespacePathForTablespace(
spcNode,
&primary_path);
/* Copy path into the passed in target location */
snprintfResult =
snprintf(target, targetMaxLen, "%s/%u/%u",
primary_path, spcNode, dbNode);
/* Throw away the allocation we got from persistent layer */
pfree(primary_path);
}
if (snprintfResult < 0)
elog(ERROR, "CopyDatabasePath formatting error");
/*
* Magically truncating the result to fit in the target string is unacceptable here
* because it can result in the wrong file-system object being referenced.
*/
if (snprintfResult >= targetMaxLen)
elog(ERROR, "CopyDatabasePath formatting result length %d exceeded the maximum length %d",
snprintfResult,
targetMaxLen);
}
