postgres/contrib/dbsize/dbsize.c

147 lines
2.6 KiB
C

#include "postgres.h"
#include <sys/types.h>
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>
#include <errno.h>
#include "access/heapam.h"
#include "catalog/catalog.h"
#include "catalog/namespace.h"
#include "commands/dbcommands.h"
#include "fmgr.h"
#include "utils/builtins.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);
Datum
database_size(PG_FUNCTION_ARGS)
{
Name dbname = PG_GETARG_NAME(0);
Oid dbid;
char *dbpath;
DIR *dirdesc;
struct dirent *direntry;
int64 totalsize;
dbid = get_database_oid(NameStr(*dbname));
if (!OidIsValid(dbid))
elog(ERROR, "database %s does not exist", NameStr(*dbname));
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(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
elog(ERROR, "could not stat %s: %m", fullname);
}
totalsize += statbuf.st_size;
pfree(fullname);
segcount++;
}
heap_close(relation, AccessShareLock);
PG_RETURN_INT64(totalsize);
}