void
SetDatabaseEncoding(int encoding)
{
if (!PG_VALID_BE_ENCODING(encoding))
elog(ERROR, "invalid database encoding: %d", encoding);
DatabaseEncoding = &pg_enc2name_tbl[encoding];
Assert(DatabaseEncoding->encoding == encoding);
}
char *
CheckerConversion(Checker *checker, char *src)
{
int len;
if (!checker->check_encoding)
return src;
len = strlen(src);
if (checker->encoding == checker->db_encoding ||
checker->encoding == PG_SQL_ASCII)
{
/*
* No conversion is needed, but we must still validate the data.
*/
pg_verify_mbstr(checker->db_encoding, src, len, false);
return src;
}
if (checker->db_encoding == PG_SQL_ASCII)
{
/*
* No conversion is possible, but we must still validate the data,
* because the client-side code might have done string escaping using
* the selected client_encoding. If the client encoding is ASCII-safe
* then we just do a straight validation under that encoding. For an
* ASCII-unsafe encoding we have a problem: we dare not pass such data
* to the parser but we have no way to convert it. We compromise by
* rejecting the data if it contains any non-ASCII characters.
*/
if (PG_VALID_BE_ENCODING(checker->encoding))
pg_verify_mbstr(checker->encoding, src, len, false);
else
{
int i;
for (i = 0; i < len; i++)
{
if (src[i] == '\0' || IS_HIGHBIT_SET(src[i]))
ereport(ERROR,
(errcode(ERRCODE_CHARACTER_NOT_IN_REPERTOIRE),
errmsg("invalid byte value for encoding \"%s\": 0x%02x",
pg_enc2name_tbl[PG_SQL_ASCII].name,
(unsigned char) src[i])));
}
}
return src;
}
/* Convert the input into the database encoding. */
return (char *) pg_do_encoding_conversion((unsigned char *) src,
len,
checker->encoding,
checker->db_encoding);
}
/*
* pg_custom_client_to_server
*
* convert client encoding to server encoding, but use the passed in encodings
* instead of the global client and server encoding variables.
*
* This routine is basically a slightly modified version of pg_client_to_server.
* Instead of creating this routine a better way may have been to just call
* pg_do_encoding_conversion(), which takes in the necessary arguments, however
* it does not do several necessary checks that pg_client_to_server() does, and
* altering it to have those check may break other parts of the system. Therefore
* until there's a better idea we resort to duplicating some code.
*
* The reason for creating this routine is to let external tables do data
* conversion reliably. Since each external table has an encoding attached to
* it we'd like to just convert from that encoding to the server encoding without
* altering the global client_encoding variable for this local database.
*/
char *
pg_custom_to_server(const char *s, int len, int src_encoding, void *cep)
{
FmgrInfo *custom_encoding_proc = (FmgrInfo *)cep;
Assert(DatabaseEncoding);
Assert(ClientEncoding);
if (len <= 0)
return (char *) s;
if (src_encoding == DatabaseEncoding->encoding ||
src_encoding == PG_SQL_ASCII)
{
/*
* No conversion is needed, but we must still validate the data.
*/
(void) pg_verify_mbstr(DatabaseEncoding->encoding, s, len, false);
return (char *) s;
}
if (DatabaseEncoding->encoding == PG_SQL_ASCII)
{
/*
* No conversion is possible, but we must still validate the data,
* because the client-side code might have done string escaping using
* the selected client_encoding. If the client encoding is ASCII-safe
* then we just do a straight validation under that encoding. For an
* ASCII-unsafe encoding we have a problem: we dare not pass such data
* to the parser but we have no way to convert it. We compromise by
* rejecting the data if it contains any non-ASCII characters.
*/
if (PG_VALID_BE_ENCODING(src_encoding))
(void) pg_verify_mbstr(src_encoding, s, len, false);
else
{
int i;
for (i = 0; i < len; i++)
{
if (s[i] == '\0' || IS_HIGHBIT_SET(s[i]))
ereport(ERROR,
(errcode(ERRCODE_CHARACTER_NOT_IN_REPERTOIRE),
errmsg("invalid byte value for encoding \"%s\": 0x%02x",
pg_enc2name_tbl[PG_SQL_ASCII].name,
(unsigned char) s[i])));
}
}
return (char *) s;
}
return perform_default_encoding_conversion(s, len, true, src_encoding, custom_encoding_proc);
}
/*
* shmem_startup hook: allocate or attach to shared memory,
* then load any pre-existing statistics from file.
*/
static void
pgss_shmem_startup(void)
{
bool found;
HASHCTL info;
FILE *file;
uint32 header;
int32 num;
int32 i;
int query_size;
int buffer_size;
char *buffer = NULL;
if (prev_shmem_startup_hook)
prev_shmem_startup_hook();
/* reset in case this is a restart within the postmaster */
pgss = NULL;
pgss_hash = NULL;
/*
* Create or attach to the shared memory state, including hash table
*/
LWLockAcquire(AddinShmemInitLock, LW_EXCLUSIVE);
pgss = ShmemInitStruct("pg_stat_statements",
sizeof(pgssSharedState),
&found);
if (!found)
{
/* First time through ... */
pgss->lock = LWLockAssign();
pgss->query_size = pgstat_track_activity_query_size;
}
/* Be sure everyone agrees on the hash table entry size */
query_size = pgss->query_size;
memset(&info, 0, sizeof(info));
info.keysize = sizeof(pgssHashKey);
info.entrysize = offsetof(pgssEntry, query) +query_size;
info.hash = pgss_hash_fn;
info.match = pgss_match_fn;
pgss_hash = ShmemInitHash("pg_stat_statements hash",
pgss_max, pgss_max,
&info,
HASH_ELEM | HASH_FUNCTION | HASH_COMPARE);
LWLockRelease(AddinShmemInitLock);
/*
* If we're in the postmaster (or a standalone backend...), set up a shmem
* exit hook to dump the statistics to disk.
*/
if (!IsUnderPostmaster)
on_shmem_exit(pgss_shmem_shutdown, (Datum) 0);
/*
* Attempt to load old statistics from the dump file, if this is the first
* time through and we weren't told not to.
*/
if (found || !pgss_save)
return;
/*
* Note: we don't bother with locks here, because there should be no other
* processes running when this code is reached.
*/
file = AllocateFile(PGSS_DUMP_FILE, PG_BINARY_R);
if (file == NULL)
{
if (errno == ENOENT)
return; /* ignore not-found error */
goto error;
}
buffer_size = query_size;
buffer = (char *) palloc(buffer_size);
if (fread(&header, sizeof(uint32), 1, file) != 1 ||
header != PGSS_FILE_HEADER ||
fread(&num, sizeof(int32), 1, file) != 1)
goto error;
for (i = 0; i < num; i++)
{
pgssEntry temp;
pgssEntry *entry;
if (fread(&temp, offsetof(pgssEntry, mutex), 1, file) != 1)
goto error;
/* Encoding is the only field we can easily sanity-check */
if (!PG_VALID_BE_ENCODING(temp.key.encoding))
goto error;
/* Previous incarnation might have had a larger query_size */
if (temp.key.query_len >= buffer_size)
{
buffer = (char *) repalloc(buffer, temp.key.query_len + 1);
buffer_size = temp.key.query_len + 1;
}
if (fread(buffer, 1, temp.key.query_len, file) != temp.key.query_len)
goto error;
buffer[temp.key.query_len] = '\0';
/* Clip to available length if needed */
if (temp.key.query_len >= query_size)
temp.key.query_len = pg_encoding_mbcliplen(temp.key.encoding,
buffer,
temp.key.query_len,
query_size - 1);
temp.key.query_ptr = buffer;
/* make the hashtable entry (discards old entries if too many) */
entry = entry_alloc(&temp.key);
/* copy in the actual stats */
entry->counters = temp.counters;
}
pfree(buffer);
FreeFile(file);
return;
error:
ereport(LOG,
(errcode_for_file_access(),
errmsg("could not read pg_stat_statement file \"%s\": %m",
PGSS_DUMP_FILE)));
if (buffer)
pfree(buffer);
if (file)
FreeFile(file);
/* If possible, throw away the bogus file; ignore any error */
unlink(PGSS_DUMP_FILE);
}
