postgresql/contrib/pg_dumplo/lo_export.c
2004-11-28 23:49:49 +00:00

220 lines
5.2 KiB
C

/* -------------------------------------------------------------------------
* pg_dumplo
*
* $PostgreSQL: pgsql/contrib/pg_dumplo/lo_export.c,v 1.13 2004/11/28 23:49:49 tgl Exp $
*
* Karel Zak 1999-2004
* -------------------------------------------------------------------------
*/
#include "postgres_fe.h"
#include <fcntl.h>
#include <errno.h>
#include <time.h>
#include <unistd.h>
#include <sys/stat.h>
#include "libpq-fe.h"
#include "libpq/libpq-fs.h"
#include "pg_dumplo.h"
extern int errno;
void
load_lolist(LODumpMaster * pgLO)
{
LOlist *ll;
int i;
int n;
/*
* Now find any candidate tables who have columns of type oid.
*
* NOTE: System tables including pg_largeobject will be ignored.
* Otherwise we'd end up dumping all LOs, referenced or not.
*
* NOTE: the system oid column is ignored, as it has attnum < 1. This
* shouldn't matter for correctness, but it saves time.
*/
pgLO->res = PQexec(pgLO->conn, "SELECT c.relname, a.attname, n.nspname "
"FROM pg_catalog.pg_class c, pg_catalog.pg_attribute a, "
" pg_catalog.pg_type t, pg_catalog.pg_namespace n "
"WHERE a.attnum > 0 "
" AND a.attrelid = c.oid "
" AND a.atttypid = t.oid "
" AND t.typname = 'oid' "
" AND c.relkind = 'r' "
" AND c.relname NOT LIKE 'pg_%' "
" AND n.oid = c.relnamespace");
if (PQresultStatus(pgLO->res) != PGRES_TUPLES_OK)
{
fprintf(stderr, "%s: Failed to get LO OIDs:\n%s", progname,
PQerrorMessage(pgLO->conn));
exit(RE_ERROR);
}
if ((n = PQntuples(pgLO->res)) == 0)
{
fprintf(stderr, "%s: No OID columns in the database.\n", progname);
exit(RE_ERROR);
}
pgLO->lolist = (LOlist *) malloc((n + 1) * sizeof(LOlist));
memset(pgLO->lolist, 0, (n + 1) * sizeof(LOlist));
if (!pgLO->lolist)
{
fprintf(stderr, "%s: can't allocate memory\n", progname);
exit(RE_ERROR);
}
for (i = 0, ll = pgLO->lolist; i < n; i++, ll++)
{
ll->lo_table = strdup(PQgetvalue(pgLO->res, i, 0));
ll->lo_attr = strdup(PQgetvalue(pgLO->res, i, 1));
ll->lo_schema = strdup(PQgetvalue(pgLO->res, i, 2));
}
PQclear(pgLO->res);
}
void
pglo_export(LODumpMaster * pgLO)
{
LOlist *ll;
int tuples;
char path[BUFSIZ],
Qbuff[QUERY_BUFSIZ];
if (pgLO->action != ACTION_SHOW)
{
time_t t;
time(&t);
fprintf(pgLO->index, "#\n# This is the PostgreSQL large object dump index\n#\n");
fprintf(pgLO->index, "#\tDate: %s", ctime(&t));
fprintf(pgLO->index, "#\tHost: %s\n", pgLO->host);
fprintf(pgLO->index, "#\tDatabase: %s\n", pgLO->db);
fprintf(pgLO->index, "#\tUser: %s\n", pgLO->user);
fprintf(pgLO->index, "#\n# oid\ttable\tattribut\tinfile\tschema\n#\n");
}
pgLO->counter = 0;
for (ll = pgLO->lolist; ll->lo_table != NULL; ll++)
{
/*
* Query: find the LOs referenced by this column
*/
snprintf(Qbuff, QUERY_BUFSIZ,
"SELECT DISTINCT l.loid FROM \"%s\".\"%s\" x, pg_catalog.pg_largeobject l "
"WHERE x.\"%s\" = l.loid",
ll->lo_schema, ll->lo_table, ll->lo_attr);
/* puts(Qbuff); */
pgLO->res = PQexec(pgLO->conn, Qbuff);
if (PQresultStatus(pgLO->res) != PGRES_TUPLES_OK)
{
fprintf(stderr, "%s: Failed to get LO OIDs:\n%s", progname,
PQerrorMessage(pgLO->conn));
}
else if ((tuples = PQntuples(pgLO->res)) == 0)
{
if (!pgLO->quiet && pgLO->action == ACTION_EXPORT_ATTR)
printf("%s: no large objects in \"%s\".\"%s\".\"%s\"\n",
progname, ll->lo_schema, ll->lo_table, ll->lo_attr);
}
else
{
int t;
char *val;
/*
* Create DIR/FILE
*/
if (pgLO->action != ACTION_SHOW)
{
snprintf(path, BUFSIZ, "%s/%s/%s", pgLO->space, pgLO->db,
ll->lo_schema);
if (mkdir(path, DIR_UMASK) == -1)
{
if (errno != EEXIST)
{
perror(path);
exit(RE_ERROR);
}
}
snprintf(path, BUFSIZ, "%s/%s/%s/%s", pgLO->space, pgLO->db,
ll->lo_schema, ll->lo_table);
if (mkdir(path, DIR_UMASK) == -1)
{
if (errno != EEXIST)
{
perror(path);
exit(RE_ERROR);
}
}
snprintf(path, BUFSIZ, "%s/%s/%s/%s/%s", pgLO->space, pgLO->db,
ll->lo_schema, ll->lo_table, ll->lo_attr);
if (mkdir(path, DIR_UMASK) == -1)
{
if (errno != EEXIST)
{
perror(path);
exit(RE_ERROR);
}
}
if (!pgLO->quiet)
printf("dump %s.%s.%s (%d large obj)\n",
ll->lo_schema, ll->lo_table, ll->lo_attr, tuples);
}
pgLO->counter += tuples;
for (t = 0; t < tuples; t++)
{
Oid lo;
val = PQgetvalue(pgLO->res, t, 0);
lo = atooid(val);
if (pgLO->action == ACTION_SHOW)
{
printf("%s.%s.%s: %u\n", ll->lo_schema, ll->lo_table, ll->lo_attr, lo);
continue;
}
snprintf(path, BUFSIZ, "%s/%s/%s/%s/%s/%s", pgLO->space,
pgLO->db, ll->lo_schema, ll->lo_table, ll->lo_attr, val);
if (lo_export(pgLO->conn, lo, path) < 0)
fprintf(stderr, "%s: lo_export failed:\n%s", progname,
PQerrorMessage(pgLO->conn));
else
fprintf(pgLO->index, "%s\t%s\t%s\t%s/%s/%s/%s/%s\t%s\n",
val, ll->lo_table, ll->lo_attr, pgLO->db,
ll->lo_schema, ll->lo_table, ll->lo_attr,
val, ll->lo_schema);
}
}
PQclear(pgLO->res);
}
}