postgresql/contrib/vacuumlo/vacuumlo.c
Bruce Momjian 7559d8ebfa Update copyrights for 2020
Backpatch-through: update all files in master, backpatch legal files through 9.4
2020-01-01 12:21:45 -05:00

560 lines
14 KiB
C

/*-------------------------------------------------------------------------
*
* vacuumlo.c
* This removes orphaned large objects from a database.
*
* Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* contrib/vacuumlo/vacuumlo.c
*
*-------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#ifdef HAVE_TERMIOS_H
#include <termios.h>
#endif
#include "catalog/pg_class_d.h"
#include "common/logging.h"
#include "fe_utils/connect.h"
#include "getopt_long.h"
#include "libpq-fe.h"
#include "pg_getopt.h"
#define BUFSIZE 1024
enum trivalue
{
TRI_DEFAULT,
TRI_NO,
TRI_YES
};
struct _param
{
char *pg_user;
enum trivalue pg_prompt;
char *pg_port;
char *pg_host;
const char *progname;
int verbose;
int dry_run;
long transaction_limit;
};
static int vacuumlo(const char *database, const struct _param *param);
static void usage(const char *progname);
/*
* This vacuums LOs of one database. It returns 0 on success, -1 on failure.
*/
static int
vacuumlo(const char *database, const struct _param *param)
{
PGconn *conn;
PGresult *res,
*res2;
char buf[BUFSIZE];
long matched;
long deleted;
int i;
bool new_pass;
bool success = true;
static bool have_password = false;
static char password[100];
/* Note: password can be carried over from a previous call */
if (param->pg_prompt == TRI_YES && !have_password)
{
simple_prompt("Password: ", password, sizeof(password), false);
have_password = true;
}
/*
* Start the connection. Loop until we have a password if requested by
* backend.
*/
do
{
#define PARAMS_ARRAY_SIZE 7
const char *keywords[PARAMS_ARRAY_SIZE];
const char *values[PARAMS_ARRAY_SIZE];
keywords[0] = "host";
values[0] = param->pg_host;
keywords[1] = "port";
values[1] = param->pg_port;
keywords[2] = "user";
values[2] = param->pg_user;
keywords[3] = "password";
values[3] = have_password ? password : NULL;
keywords[4] = "dbname";
values[4] = database;
keywords[5] = "fallback_application_name";
values[5] = param->progname;
keywords[6] = NULL;
values[6] = NULL;
new_pass = false;
conn = PQconnectdbParams(keywords, values, true);
if (!conn)
{
pg_log_error("connection to database \"%s\" failed", database);
return -1;
}
if (PQstatus(conn) == CONNECTION_BAD &&
PQconnectionNeedsPassword(conn) &&
!have_password &&
param->pg_prompt != TRI_NO)
{
PQfinish(conn);
simple_prompt("Password: ", password, sizeof(password), false);
have_password = true;
new_pass = true;
}
} while (new_pass);
/* check to see that the backend connection was successfully made */
if (PQstatus(conn) == CONNECTION_BAD)
{
pg_log_error("connection to database \"%s\" failed: %s",
database, PQerrorMessage(conn));
PQfinish(conn);
return -1;
}
if (param->verbose)
{
fprintf(stdout, "Connected to database \"%s\"\n", database);
if (param->dry_run)
fprintf(stdout, "Test run: no large objects will be removed!\n");
}
res = PQexec(conn, ALWAYS_SECURE_SEARCH_PATH_SQL);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{
pg_log_error("failed to set search_path: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res);
/*
* First we create and populate the LO temp table
*/
buf[0] = '\0';
strcat(buf, "CREATE TEMP TABLE vacuum_l AS ");
if (PQserverVersion(conn) >= 90000)
strcat(buf, "SELECT oid AS lo FROM pg_largeobject_metadata");
else
strcat(buf, "SELECT DISTINCT loid AS lo FROM pg_largeobject");
res = PQexec(conn, buf);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
pg_log_error("failed to create temp table: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res);
/*
* Analyze the temp table so that planner will generate decent plans for
* the DELETEs below.
*/
buf[0] = '\0';
strcat(buf, "ANALYZE vacuum_l");
res = PQexec(conn, buf);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
pg_log_error("failed to vacuum temp table: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res);
/*
* Now find any candidate tables that have columns of type oid.
*
* NOTE: we ignore system tables and temp tables by the expedient of
* rejecting tables in schemas named 'pg_*'. In particular, the temp
* table formed above is ignored, and pg_largeobject will be too. If
* either of these were scanned, obviously we'd end up with nothing to
* delete...
*/
buf[0] = '\0';
strcat(buf, "SELECT s.nspname, c.relname, a.attname ");
strcat(buf, "FROM pg_class c, pg_attribute a, pg_namespace s, pg_type t ");
strcat(buf, "WHERE a.attnum > 0 AND NOT a.attisdropped ");
strcat(buf, " AND a.attrelid = c.oid ");
strcat(buf, " AND a.atttypid = t.oid ");
strcat(buf, " AND c.relnamespace = s.oid ");
strcat(buf, " AND t.typname in ('oid', 'lo') ");
strcat(buf, " AND c.relkind in (" CppAsString2(RELKIND_RELATION) ", " CppAsString2(RELKIND_MATVIEW) ")");
strcat(buf, " AND s.nspname !~ '^pg_'");
res = PQexec(conn, buf);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{
pg_log_error("failed to find OID columns: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
for (i = 0; i < PQntuples(res); i++)
{
char *schema,
*table,
*field;
schema = PQgetvalue(res, i, 0);
table = PQgetvalue(res, i, 1);
field = PQgetvalue(res, i, 2);
if (param->verbose)
fprintf(stdout, "Checking %s in %s.%s\n", field, schema, table);
schema = PQescapeIdentifier(conn, schema, strlen(schema));
table = PQescapeIdentifier(conn, table, strlen(table));
field = PQescapeIdentifier(conn, field, strlen(field));
if (!schema || !table || !field)
{
pg_log_error("%s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
if (schema != NULL)
PQfreemem(schema);
if (table != NULL)
PQfreemem(table);
if (field != NULL)
PQfreemem(field);
return -1;
}
snprintf(buf, BUFSIZE,
"DELETE FROM vacuum_l "
"WHERE lo IN (SELECT %s FROM %s.%s)",
field, schema, table);
res2 = PQexec(conn, buf);
if (PQresultStatus(res2) != PGRES_COMMAND_OK)
{
pg_log_error("failed to check %s in table %s.%s: %s",
field, schema, table, PQerrorMessage(conn));
PQclear(res2);
PQclear(res);
PQfinish(conn);
PQfreemem(schema);
PQfreemem(table);
PQfreemem(field);
return -1;
}
PQclear(res2);
PQfreemem(schema);
PQfreemem(table);
PQfreemem(field);
}
PQclear(res);
/*
* Now, those entries remaining in vacuum_l are orphans. Delete 'em.
*
* We don't want to run each delete as an individual transaction, because
* the commit overhead would be high. However, since 9.0 the backend will
* acquire a lock per deleted LO, so deleting too many LOs per transaction
* risks running out of room in the shared-memory lock table. Accordingly,
* we delete up to transaction_limit LOs per transaction.
*/
res = PQexec(conn, "begin");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
pg_log_error("failed to start transaction: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res);
buf[0] = '\0';
strcat(buf,
"DECLARE myportal CURSOR WITH HOLD FOR SELECT lo FROM vacuum_l");
res = PQexec(conn, buf);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
pg_log_error("DECLARE CURSOR failed: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res);
snprintf(buf, BUFSIZE, "FETCH FORWARD %ld IN myportal",
param->transaction_limit > 0 ? param->transaction_limit : 1000L);
deleted = 0;
do
{
res = PQexec(conn, buf);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{
pg_log_error("FETCH FORWARD failed: %s", PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
matched = PQntuples(res);
if (matched <= 0)
{
/* at end of resultset */
PQclear(res);
break;
}
for (i = 0; i < matched; i++)
{
Oid lo = atooid(PQgetvalue(res, i, 0));
if (param->verbose)
{
fprintf(stdout, "\rRemoving lo %6u ", lo);
fflush(stdout);
}
if (param->dry_run == 0)
{
if (lo_unlink(conn, lo) < 0)
{
pg_log_error("failed to remove lo %u: %s", lo,
PQerrorMessage(conn));
if (PQtransactionStatus(conn) == PQTRANS_INERROR)
{
success = false;
break; /* out of inner for-loop */
}
}
else
deleted++;
}
else
deleted++;
if (param->transaction_limit > 0 &&
(deleted % param->transaction_limit) == 0)
{
res2 = PQexec(conn, "commit");
if (PQresultStatus(res2) != PGRES_COMMAND_OK)
{
pg_log_error("failed to commit transaction: %s",
PQerrorMessage(conn));
PQclear(res2);
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res2);
res2 = PQexec(conn, "begin");
if (PQresultStatus(res2) != PGRES_COMMAND_OK)
{
pg_log_error("failed to start transaction: %s",
PQerrorMessage(conn));
PQclear(res2);
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res2);
}
}
PQclear(res);
} while (success);
/*
* That's all folks!
*/
res = PQexec(conn, "commit");
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
pg_log_error("failed to commit transaction: %s",
PQerrorMessage(conn));
PQclear(res);
PQfinish(conn);
return -1;
}
PQclear(res);
PQfinish(conn);
if (param->verbose)
{
if (param->dry_run)
fprintf(stdout, "\rWould remove %ld large objects from database \"%s\".\n",
deleted, database);
else if (success)
fprintf(stdout,
"\rSuccessfully removed %ld large objects from database \"%s\".\n",
deleted, database);
else
fprintf(stdout, "\rRemoval from database \"%s\" failed at object %ld of %ld.\n",
database, deleted, matched);
}
return ((param->dry_run || success) ? 0 : -1);
}
static void
usage(const char *progname)
{
printf("%s removes unreferenced large objects from databases.\n\n", progname);
printf("Usage:\n %s [OPTION]... DBNAME...\n\n", progname);
printf("Options:\n");
printf(" -l, --limit=LIMIT commit after removing each LIMIT large objects\n");
printf(" -n, --dry-run don't remove large objects, just show what would be done\n");
printf(" -v, --verbose write a lot of progress messages\n");
printf(" -V, --version output version information, then exit\n");
printf(" -?, --help show this help, then exit\n");
printf("\nConnection options:\n");
printf(" -h, --host=HOSTNAME database server host or socket directory\n");
printf(" -p, --port=PORT database server port\n");
printf(" -U, --username=USERNAME user name to connect as\n");
printf(" -w, --no-password never prompt for password\n");
printf(" -W, --password force password prompt\n");
printf("\n");
printf("Report bugs to <pgsql-bugs@lists.postgresql.org>.\n");
}
int
main(int argc, char **argv)
{
static struct option long_options[] = {
{"host", required_argument, NULL, 'h'},
{"limit", required_argument, NULL, 'l'},
{"dry-run", no_argument, NULL, 'n'},
{"port", required_argument, NULL, 'p'},
{"username", required_argument, NULL, 'U'},
{"verbose", no_argument, NULL, 'v'},
{"version", no_argument, NULL, 'V'},
{"no-password", no_argument, NULL, 'w'},
{"password", no_argument, NULL, 'W'},
{"help", no_argument, NULL, '?'},
{NULL, 0, NULL, 0}
};
int rc = 0;
struct _param param;
int c;
int port;
const char *progname;
int optindex;
pg_logging_init(argv[0]);
progname = get_progname(argv[0]);
/* Set default parameter values */
param.pg_user = NULL;
param.pg_prompt = TRI_DEFAULT;
param.pg_host = NULL;
param.pg_port = NULL;
param.progname = progname;
param.verbose = 0;
param.dry_run = 0;
param.transaction_limit = 1000;
/* Process command-line arguments */
if (argc > 1)
{
if (strcmp(argv[1], "--help") == 0 || strcmp(argv[1], "-?") == 0)
{
usage(progname);
exit(0);
}
if (strcmp(argv[1], "--version") == 0 || strcmp(argv[1], "-V") == 0)
{
puts("vacuumlo (PostgreSQL) " PG_VERSION);
exit(0);
}
}
while ((c = getopt_long(argc, argv, "h:l:np:U:vwW", long_options, &optindex)) != -1)
{
switch (c)
{
case '?':
fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
exit(1);
case 'h':
param.pg_host = pg_strdup(optarg);
break;
case 'l':
param.transaction_limit = strtol(optarg, NULL, 10);
if (param.transaction_limit < 0)
{
pg_log_error("transaction limit must not be negative (0 disables)");
exit(1);
}
break;
case 'n':
param.dry_run = 1;
param.verbose = 1;
break;
case 'p':
port = strtol(optarg, NULL, 10);
if ((port < 1) || (port > 65535))
{
pg_log_error("invalid port number: %s", optarg);
exit(1);
}
param.pg_port = pg_strdup(optarg);
break;
case 'U':
param.pg_user = pg_strdup(optarg);
break;
case 'v':
param.verbose = 1;
break;
case 'w':
param.pg_prompt = TRI_NO;
break;
case 'W':
param.pg_prompt = TRI_YES;
break;
default:
fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
exit(1);
}
}
/* No database given? Show usage */
if (optind >= argc)
{
pg_log_error("missing required argument: database name");
fprintf(stderr, _("Try \"%s --help\" for more information.\n"), progname);
exit(1);
}
for (c = optind; c < argc; c++)
{
/* Work on selected database */
rc += (vacuumlo(argv[c], &param) != 0);
}
return rc;
}