mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2025-03-07 19:47:50 +08:00
Code Issues Packages Projects Releases Wiki Activity

Improve error detection and recovery in lo_import()/lo_export().

Browse Source 
Problems noted while experimenting with new control-C code for psql.
This commit is contained in:
Tom Lane 2006-06-14 01:28:55 +00:00
parent 067e40cc6d
commit ace93353ea
1 changed files with 56 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

85
src/interfaces/libpq/fe-lobj.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/interfaces/libpq/fe-lobj.c,v 1.56 2006/03/05 15:59:09 momjian Exp $
* $PostgreSQL: pgsql/src/interfaces/libpq/fe-lobj.c,v 1.57 2006/06/14 01:28:55 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -58,6 +58,12 @@ lo_open(PGconn *conn, Oid lobjId, int mode)
PQArgBlock argv[2];
PGresult *res;
if (conn->lobjfuncs == NULL)
{
if (lo_initialize(conn) < 0)
return -1;
}
argv[0].isint = 1;
argv[0].len = 4;
argv[0].u.integer = lobjId;
@ -66,12 +72,6 @@ lo_open(PGconn *conn, Oid lobjId, int mode)
argv[1].len = 4;
argv[1].u.integer = mode;
if (conn->lobjfuncs == NULL)
{
if (lo_initialize(conn) < 0)
return -1;
}
res = PQfn(conn, conn->lobjfuncs->fn_lo_open, &fd, &result_len, 1, argv, 2);
if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
@ -438,6 +438,7 @@ lo_import(PGconn *conn, const char *filename)
char buf[LO_BUFSIZE];
Oid lobjOid;
int lobj;
char sebuf[256];
/*
* open the file to be read in
@ -445,8 +446,6 @@ lo_import(PGconn *conn, const char *filename)
fd = open(filename, O_RDONLY | PG_BINARY, 0666);
if (fd < 0)
{ /* error */
char sebuf[256];
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not open file \"%s\": %s\n"),
filename, pqStrerror(errno, sebuf, sizeof(sebuf)));
@ -454,7 +453,7 @@ lo_import(PGconn *conn, const char *filename)
}
/*
* create an inversion "object"
* create an inversion object
*/
lobjOid = lo_creat(conn, INV_READ | INV_WRITE);
if (lobjOid == InvalidOid)
@ -477,24 +476,46 @@ lo_import(PGconn *conn, const char *filename)
}
/*
* read in from the Unix file and write to the inversion file
* read in from the file and write to the large object
*/
while ((nbytes = read(fd, buf, LO_BUFSIZE)) > 0)
{
tmp = lo_write(conn, lobj, buf, nbytes);
if (tmp < nbytes)
if (tmp != nbytes)
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("error while reading file \"%s\"\n"),
filename);
(void) close(fd);
/*
* If the lo_write failed, we are probably in an aborted
* transaction and so lo_close will fail. Try it anyway for
* cleanliness, but don't let it determine the returned error
* message.
*/
(void) lo_close(conn, lobj);
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("error while writing large object %u\n"),
lobjOid);
(void) close(fd);
return InvalidOid;
}
}
if (nbytes < 0)
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not read from file \"%s\": %s\n"),
filename, pqStrerror(errno, sebuf, sizeof(sebuf)));
lobjOid = InvalidOid;
}
(void) close(fd);
(void) lo_close(conn, lobj);
if (lo_close(conn, lobj) != 0)
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("error while writing large object %u\n"),
lobjOid);
return InvalidOid;
}
return lobjOid;
}
@ -502,16 +523,18 @@ lo_import(PGconn *conn, const char *filename)
/*
* lo_export -
* exports an (inversion) large object.
* returns -1 upon failure, 1 otherwise
* returns -1 upon failure, 1 if OK
*/
int
lo_export(PGconn *conn, Oid lobjId, const char *filename)
{
int result = 1;
int fd;
int nbytes,
tmp;
char buf[LO_BUFSIZE];
int lobj;
char sebuf[256];
/*
* open the large object.
@ -530,8 +553,6 @@ lo_export(PGconn *conn, Oid lobjId, const char *filename)
fd = open(filename, O_CREAT | O_WRONLY | O_TRUNC | PG_BINARY, 0666);
if (fd < 0)
{ /* error */
char sebuf[256];
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("could not open file \"%s\": %s\n"),
filename, pqStrerror(errno, sebuf, sizeof(sebuf)));
@ -540,33 +561,39 @@ lo_export(PGconn *conn, Oid lobjId, const char *filename)
}
/*
* read in from the inversion file and write to the Unix file
* read in from the large object and write to the file
*/
while ((nbytes = lo_read(conn, lobj, buf, LO_BUFSIZE)) > 0)
{
tmp = write(fd, buf, nbytes);
if (tmp < nbytes)
if (tmp != nbytes)
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("error while writing to file \"%s\"\n"),
filename);
libpq_gettext("error while writing to file \"%s\": %s\n"),
filename, pqStrerror(errno, sebuf, sizeof(sebuf)));
(void) lo_close(conn, lobj);
(void) close(fd);
return -1;
}
}
(void) lo_close(conn, lobj);
if (lo_close(conn, lobj) != 0 || nbytes < 0)
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("error while reading large object %u\n"),
lobjId);
result = -1;
}
if (close(fd))
{
printfPQExpBuffer(&conn->errorMessage,
libpq_gettext("error while writing to file \"%s\"\n"),
filename);
return -1;
libpq_gettext("error while writing to file \"%s\": %s\n"),
filename, pqStrerror(errno, sebuf, sizeof(sebuf)));
result = -1;
}
return 1;
return result;
}