read_ntfs_file_prefix(const struct wim_lookup_table_entry *lte,
u64 size,
consume_data_callback_t cb,
- u32 in_chunk_size,
- void *ctx_or_buf,
+ void *cb_ctx,
int _ignored_flags)
{
struct ntfs_location *loc = lte->ntfs_loc;
ntfs_attr *na;
s64 pos;
s64 bytes_remaining;
- void *out_buf;
- bool out_buf_malloced;
int ret;
+ u8 buf[BUFFER_SIZE];
ni = ntfs_pathname_to_inode(vol, NULL, loc->path);
if (!ni) {
goto out_close_ntfs_inode;
}
- out_buf_malloced = false;
- if (cb) {
- if (in_chunk_size <= STACK_MAX) {
- out_buf = alloca(in_chunk_size);
- } else {
- out_buf = MALLOC(in_chunk_size);
- if (out_buf == NULL) {
- ret = WIMLIB_ERR_NOMEM;
- goto out_close_ntfs_attr;
- }
- out_buf_malloced = true;
- }
- } else {
- out_buf = ctx_or_buf;
- }
pos = (loc->is_reparse_point) ? 8 : 0;
bytes_remaining = size;
while (bytes_remaining) {
- s64 to_read = min(bytes_remaining, in_chunk_size);
- if (ntfs_attr_pread(na, pos, to_read, out_buf) != to_read) {
+ s64 to_read = min(bytes_remaining, sizeof(buf));
+ if (ntfs_attr_pread(na, pos, to_read, buf) != to_read) {
ERROR_WITH_ERRNO("Error reading \"%"TS"\"", loc->path);
ret = WIMLIB_ERR_NTFS_3G;
- goto out_free_memory;
+ goto out_close_ntfs_attr;
}
pos += to_read;
bytes_remaining -= to_read;
- if (cb) {
- ret = cb(out_buf, to_read, ctx_or_buf);
- if (ret)
- goto out_free_memory;
- } else {
- out_buf += to_read;
- }
+ ret = cb(buf, to_read, cb_ctx);
+ if (ret)
+ goto out_close_ntfs_attr;
}
ret = 0;
-out_free_memory:
- if (out_buf_malloced)
- FREE(out_buf);
out_close_ntfs_attr:
ntfs_attr_close(na);
out_close_ntfs_inode: