static int64_t http_seek(URLContext *h, int64_t off, int whence) { HTTPContext *s = h->priv_data; URLContext *old_hd = s->hd; int64_t old_off = s->off; uint8_t old_buf[BUFFER_SIZE]; int old_buf_size; AVDictionary *options = NULL; if (whence == AVSEEK_SIZE) return s->filesize; else if ((whence == SEEK_CUR && off == 0) || (whence == SEEK_SET && off == s->off)) return s->off; else if ((s->filesize == -1 && whence == SEEK_END) || h->is_streamed) return -1; /* we save the old context in case the seek fails */ old_buf_size = s->buf_end - s->buf_ptr; memcpy(old_buf, s->buf_ptr, old_buf_size); s->hd = NULL; if (whence == SEEK_CUR) off += s->off; else if (whence == SEEK_END) off += s->filesize; s->off = off; /* if it fails, continue on old connection */ av_dict_copy(&options, s->chained_options, 0); if (http_open_cnx(h, &options) < 0) { av_dict_free(&options); memcpy(s->buffer, old_buf, old_buf_size); s->buf_ptr = s->buffer; s->buf_end = s->buffer + old_buf_size; s->hd = old_hd; s->off = old_off; return -1; } av_dict_free(&options); ffurl_close(old_hd); return off; }