static gboolean
flush_buffer(
amar_t *archive,
GError **error)
{
if (archive->buf_len) {
if (full_write(archive->fd, archive->buf, archive->buf_len) != archive->buf_len) {
g_set_error(error, amar_error_quark(), errno,
"Error writing to amanda archive: %s", strerror(errno));
return FALSE;
}
archive->buf_len = 0;
}
return TRUE;
}
static gboolean
write_record(
amar_t *archive,
amar_file_t *file,
guint16 attrid,
gboolean eoa,
gpointer data,
gsize data_size,
GError **error)
{
/* the buffer always has room for a new record header */
MKRECORD(archive->buf + archive->buf_len, file->filenum, attrid, data_size, eoa);
archive->buf_len += RECORD_SIZE;
/* is it worth copying this record into the buffer? */
if (archive->buf_len + RECORD_SIZE + data_size < WRITE_BUFFER_SIZE - RECORD_SIZE) {
/* yes, it is */
if (data_size)
memcpy(archive->buf + archive->buf_len, data, data_size);
archive->buf_len += data_size;
} else {
/* no, it's not */
struct iovec iov[2];
/* flush the buffer and write the new data, all in one syscall */
iov[0].iov_base = archive->buf;
iov[0].iov_len = archive->buf_len;
iov[1].iov_base = data;
iov[1].iov_len = data_size;
if (full_writev(archive->fd, iov, 2) < 0) {
g_set_error(error, amar_error_quark(), errno,
"Error writing to amanda archive: %s", strerror(errno));
return FALSE;
}
archive->buf_len = 0;
}
archive->position += data_size + RECORD_SIZE;
file->size += data_size + RECORD_SIZE;
return TRUE;
}
amar_file_t *
amar_new_file(
amar_t *archive,
char *filename_buf,
gsize filename_len,
off_t *header_offset,
GError **error)
{
amar_file_t *file = NULL;
g_assert(archive->mode == O_WRONLY);
g_assert(filename_buf != NULL);
/* set filename_len if it wasn't specified */
if (!filename_len)
filename_len = strlen(filename_buf);
g_assert(filename_len != 0);
if (filename_len > MAX_RECORD_DATA_SIZE) {
g_set_error(error, amar_error_quark(), ENOSPC,
"filename is too long for an amanda archive");
return NULL;
}
/* pick a new, unused filenum */
if (g_hash_table_size(archive->files) == 65535) {
g_set_error(error, amar_error_quark(), ENOSPC,
"No more file numbers available");
return NULL;
}
do {
gint filenum;
archive->maxfilenum++;
/* MAGIC_FILENUM can't be used because it matches the header record text */
if (archive->maxfilenum == MAGIC_FILENUM) {
continue;
}
/* see if this fileid is already in use */
filenum = archive->maxfilenum;
if (g_hash_table_lookup(archive->files, &filenum))
continue;
} while (0);
file = g_new0(amar_file_t, 1);
if (!file) {
g_set_error(error, amar_error_quark(), ENOSPC,
"No more memory");
return NULL;
}
file->archive = archive;
file->filenum = archive->maxfilenum;
file->attributes = g_hash_table_new_full(g_int_hash, g_int_equal, NULL, g_free);
g_hash_table_insert(archive->files, &file->filenum, file);
/* record the current position and write a header there, if desired */
if (header_offset) {
*header_offset = archive->position;
if (!write_header(archive, error))
goto error_exit;
}
/* add a filename record */
if (!write_record(archive, file->filenum, AMAR_ATTR_FILENAME,
1, filename_buf, filename_len, error))
goto error_exit;
return file;
error_exit:
if (file) {
g_hash_table_remove(archive->files, &file->filenum);
g_hash_table_destroy(file->attributes);
g_free(file);
}
return NULL;
}