postgresql/contrib/dbsize/dbsize.c
2004-08-29 05:07:03 +00:00

203 lines
3.9 KiB
C

#include "postgres.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "access/heapam.h"
#include "catalog/catalog.h"
#include "catalog/catname.h"
#include "catalog/namespace.h"
#include "catalog/pg_tablespace.h"
#include "commands/dbcommands.h"
#include "fmgr.h"
#include "storage/fd.h"
#include "utils/builtins.h"
static int64
get_tablespace_size(Oid dbid, Oid spcid, bool baddirOK);
static char *
psnprintf(size_t len, const char *fmt,...)
{
va_list ap;
char *buf;
buf = palloc(len);
va_start(ap, fmt);
vsnprintf(buf, len, fmt, ap);
va_end(ap);
return buf;
}
/*
* SQL function: database_size(name) returns bigint
*/
PG_FUNCTION_INFO_V1(database_size);
Datum database_size(PG_FUNCTION_ARGS);
Datum
database_size(PG_FUNCTION_ARGS)
{
Name dbname = PG_GETARG_NAME(0);
Oid dbid;
int64 totalsize;
#ifdef SYMLINK
Relation dbrel;
HeapScanDesc scan;
HeapTuple tuple;
#endif
dbid = get_database_oid(NameStr(*dbname));
if (!OidIsValid(dbid))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_DATABASE),
errmsg("database \"%s\" does not exist", NameStr(*dbname))));
#ifdef SYMLINK
dbrel = heap_openr(TableSpaceRelationName, AccessShareLock);
scan = heap_beginscan(dbrel, SnapshotNow, 0, (ScanKey) NULL);
totalsize = 0;
while ((tuple = heap_getnext(scan, ForwardScanDirection)))
{
Oid spcid = HeapTupleGetOid(tuple);
if (spcid != GLOBALTABLESPACE_OID)
totalsize += get_tablespace_size(dbid, spcid, true);
}
heap_endscan(scan);
heap_close(dbrel, AccessShareLock);
#else
/* Same as always */
totalsize = get_tablespace_size(dbid, DEFAULTTABLESPACE_OID, false);
#endif
/*
* We need to keep in mind that we may not be called from the database
* whose size we're reporting so, we need to look in every tablespace
* to see if our database has data in there
*/
PG_RETURN_INT64(totalsize);
}
static int64
get_tablespace_size(Oid dbid, Oid spcid, bool baddirOK)
{
char *dbpath;
DIR *dirdesc;
struct dirent *direntry;
int64 totalsize;
dbpath = GetDatabasePath(dbid, spcid);
dirdesc = AllocateDir(dbpath);
if (!dirdesc)
{
if (baddirOK)
return 0;
else
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not open directory \"%s\": %m", dbpath)));
}
totalsize = 0;
for (;;)
{
char *fullname;
struct stat statbuf;
errno = 0;
direntry = readdir(dirdesc);
if (!direntry)
{
if (errno)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("error reading directory: %m")));
else
break;
}
fullname = psnprintf(strlen(dbpath) + 1 + strlen(direntry->d_name) + 1,
"%s/%s", dbpath, direntry->d_name);
if (stat(fullname, &statbuf) == -1)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not stat \"%s\": %m", fullname)));
totalsize += statbuf.st_size;
pfree(fullname);
}
FreeDir(dirdesc);
return (totalsize);
}
/*
* SQL function: relation_size(text) returns bigint
*/
PG_FUNCTION_INFO_V1(relation_size);
Datum relation_size(PG_FUNCTION_ARGS);
Datum
relation_size(PG_FUNCTION_ARGS)
{
text *relname = PG_GETARG_TEXT_P(0);
RangeVar *relrv;
Relation relation;
Oid relnode;
int64 totalsize;
unsigned int segcount;
relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname,
"relation_size"));
relation = heap_openrv(relrv, AccessShareLock);
relnode = relation->rd_rel->relfilenode;
totalsize = 0;
segcount = 0;
for (;;)
{
char *fullname;
struct stat statbuf;
if (segcount == 0)
fullname = psnprintf(25, "%u", (unsigned) relnode);
else
fullname = psnprintf(50, "%u.%u", (unsigned) relnode, segcount);
if (stat(fullname, &statbuf) == -1)
{
if (errno == ENOENT)
break;
else
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not stat \"%s\": %m", fullname)));
}
totalsize += statbuf.st_size;
pfree(fullname);
segcount++;
}
heap_close(relation, AccessShareLock);
PG_RETURN_INT64(totalsize);
}