postgresql/contrib/dbsize/dbsize.c
Bruce Momjian ad0787b2bd I've written on like that a while ago:
http://webmail.postgresql.org/~petere/dbsize.html

The tarball can be rolled into contrib -- now that I think of it I don't
know why I never did that.

Never imagined this would have anything to do with that TODO item,
though.
I figured oid2name accomplished that.

Peter Eisentraut   peter_e@gmx.net
2002-02-22 23:05:35 +00:00

170 lines
3.4 KiB
C

#include "postgres.h"
#include "fmgr.h"
#include "access/heapam.h"
#include "catalog/catalog.h"
#include "catalog/catname.h"
#include "catalog/pg_database.h"
#include "utils/fmgroids.h"
#include <stdlib.h>
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
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)
{
Name dbname = PG_GETARG_NAME(0);
HeapTuple tuple;
Relation relation;
ScanKeyData scanKey;
HeapScanDesc scan;
Oid dbid;
char *dbpath;
DIR *dirdesc;
struct dirent *direntry;
int64 totalsize;
relation = heap_openr(DatabaseRelationName, AccessShareLock);
ScanKeyEntryInitialize(&scanKey, 0, Anum_pg_database_datname,
F_NAMEEQ, NameGetDatum(dbname));
scan = heap_beginscan(relation, 0, SnapshotNow, 1, &scanKey);
tuple = heap_getnext(scan, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "database %s does not exist", NameStr(*dbname));
dbid = tuple->t_data->t_oid;
if (dbid == InvalidOid)
elog(ERROR, "invalid database id");
heap_endscan(scan);
heap_close(relation, NoLock);
dbpath = GetDatabasePath(dbid);
dirdesc = opendir(dbpath);
if (!dirdesc)
elog(ERROR, "could not open directory %s: %s", dbpath, strerror(errno));
totalsize = 0;
for (;;)
{
char *fullname;
struct stat statbuf;
errno = 0;
direntry = readdir(dirdesc);
if (!direntry)
{
if (errno)
elog(ERROR, "error reading directory: %s", strerror(errno));
else
break;
}
fullname = psnprintf(strlen(dbpath) + 1 + strlen(direntry->d_name) + 1,
"%s/%s", dbpath, direntry->d_name);
if (stat(fullname, &statbuf) == -1)
elog(ERROR, "could not stat %s: %s", fullname, strerror(errno));
totalsize += statbuf.st_size;
pfree(fullname);
}
closedir(dirdesc);
PG_RETURN_INT64(totalsize);
}
/*
* SQL function: relation_size(name) returns bigint
*/
PG_FUNCTION_INFO_V1(relation_size);
Datum
relation_size(PG_FUNCTION_ARGS)
{
Name relname = PG_GETARG_NAME(0);
HeapTuple tuple;
Relation relation;
ScanKeyData scanKey;
HeapScanDesc scan;
Oid relnode;
int64 totalsize;
unsigned int segcount;
relation = heap_openr(RelationRelationName, AccessShareLock);
ScanKeyEntryInitialize(&scanKey, 0, Anum_pg_class_relname,
F_NAMEEQ, NameGetDatum(relname));
scan = heap_beginscan(relation, 0, SnapshotNow, 1, &scanKey);
tuple = heap_getnext(scan, 0);
if (!HeapTupleIsValid(tuple))
elog(ERROR, "relation %s does not exist", NameStr(*relname));
relnode = ((Form_pg_class) GETSTRUCT(tuple))->relfilenode;
if (relnode == InvalidOid)
elog(ERROR, "invalid relation node id");
heap_endscan(scan);
heap_close(relation, NoLock);
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
elog(ERROR, "could not stat %s: %s", fullname, strerror(errno));
}
totalsize += statbuf.st_size;
pfree(fullname);
segcount++;
}
PG_RETURN_INT64(totalsize);
}