diff options
Diffstat (limited to 'subversion/libsvn_delta/text_delta.c')
| -rw-r--r-- | subversion/libsvn_delta/text_delta.c | 175 |
1 files changed, 150 insertions, 25 deletions
diff --git a/subversion/libsvn_delta/text_delta.c b/subversion/libsvn_delta/text_delta.c index ba35ba6..be2c434 100644 --- a/subversion/libsvn_delta/text_delta.c +++ b/subversion/libsvn_delta/text_delta.c @@ -57,7 +57,8 @@ struct txdelta_baton { svn_filesize_t pos; /* Offset of next read in source file. */ char *buf; /* Buffer for input data. */ - svn_checksum_ctx_t *context; /* Context for computing the checksum. */ + svn_checksum_ctx_t *context; /* If not NULL, the context for computing + the checksum. */ svn_checksum_t *checksum; /* If non-NULL, the checksum of TARGET. */ apr_pool_t *result_pool; /* For results (e.g. checksum) */ @@ -150,7 +151,7 @@ compute_window(const char *data, apr_size_t source_len, apr_size_t target_len, svn_txdelta_window_t *window; /* Compute the delta operations. */ - build_baton.new_data = svn_stringbuf_create("", pool); + build_baton.new_data = svn_stringbuf_create_empty(pool); if (source_len == 0) svn_txdelta__insert_op(&build_baton, svn_txdelta_new, 0, target_len, data, @@ -276,6 +277,48 @@ svn_txdelta__insert_op(svn_txdelta__ops_baton_t *build_baton, ++build_baton->num_ops; } +apr_size_t +svn_txdelta__remove_copy(svn_txdelta__ops_baton_t *build_baton, + apr_size_t max_len) +{ + svn_txdelta_op_t *op; + apr_size_t len = 0; + + /* remove ops back to front */ + while (build_baton->num_ops > 0) + { + op = &build_baton->ops[build_baton->num_ops-1]; + + /* we can't modify svn_txdelta_target ops -> stop there */ + if (op->action_code == svn_txdelta_target) + break; + + /* handle the case that we cannot remove the op entirely */ + if (op->length + len > max_len) + { + /* truncate only insertions. Copies don't benefit + from being truncated. */ + if (op->action_code == svn_txdelta_new) + { + build_baton->new_data->len -= max_len - len; + op->length -= max_len - len; + len = max_len; + } + + break; + } + + /* drop the op entirely */ + if (op->action_code == svn_txdelta_new) + build_baton->new_data->len -= op->length; + + len += op->length; + --build_baton->num_ops; + } + + return len; +} + /* Generic delta stream functions. */ @@ -363,6 +406,10 @@ txdelta_md5_digest(void *baton) if (b->more) return NULL; + /* If checksumming has not been activated, there will be no digest. */ + if (b->context == NULL) + return NULL; + /* The checksum should be there. */ return b->checksum->digest; } @@ -421,10 +468,11 @@ svn_txdelta_run(svn_stream_t *source, void -svn_txdelta(svn_txdelta_stream_t **stream, - svn_stream_t *source, - svn_stream_t *target, - apr_pool_t *pool) +svn_txdelta2(svn_txdelta_stream_t **stream, + svn_stream_t *source, + svn_stream_t *target, + svn_boolean_t calculate_checksum, + apr_pool_t *pool) { struct txdelta_baton *b = apr_pcalloc(pool, sizeof(*b)); @@ -433,13 +481,24 @@ svn_txdelta(svn_txdelta_stream_t **stream, b->more_source = TRUE; b->more = TRUE; b->buf = apr_palloc(pool, 2 * SVN_DELTA_WINDOW_SIZE); - b->context = svn_checksum_ctx_create(svn_checksum_md5, pool); + b->context = calculate_checksum + ? svn_checksum_ctx_create(svn_checksum_md5, pool) + : NULL; b->result_pool = pool; *stream = svn_txdelta_stream_create(b, txdelta_next_window, txdelta_md5_digest, pool); } +void +svn_txdelta(svn_txdelta_stream_t **stream, + svn_stream_t *source, + svn_stream_t *target, + apr_pool_t *pool) +{ + svn_txdelta2(stream, source, target, TRUE, pool); +} + /* Functions for implementing a "target push" delta. */ @@ -650,6 +709,7 @@ svn_txdelta_apply_instructions(svn_txdelta_window_t *window, { case svn_txdelta_source: /* Copy from source area. */ + assert(sbuf); assert(op->offset + op->length <= window->sview_len); fast_memcpy(tbuf + tpos, sbuf + op->offset, buf_len); break; @@ -742,7 +802,8 @@ apply_window(svn_txdelta_window_t *window, void *baton) /* If the existing view overlaps with the new view, copy the * overlap to the beginning of the new buffer. */ - if (ab->sbuf_offset + ab->sbuf_len > window->sview_offset) + if ( (apr_size_t)ab->sbuf_offset + ab->sbuf_len + > (apr_size_t)window->sview_offset) { apr_size_t start = (apr_size_t)(window->sview_offset - ab->sbuf_offset); @@ -862,29 +923,54 @@ svn_error_t *svn_txdelta_send_stream(svn_stream_t *stream, unsigned char *digest, apr_pool_t *pool) { - svn_txdelta_stream_t *txstream; - svn_error_t *err; + svn_txdelta_window_t delta_window = { 0 }; + svn_txdelta_op_t delta_op; + svn_string_t window_data; + char read_buf[SVN__STREAM_CHUNK_SIZE + 1]; + svn_checksum_ctx_t *md5_checksum_ctx; + + if (digest) + md5_checksum_ctx = svn_checksum_ctx_create(svn_checksum_md5, pool); + + while (1) + { + apr_size_t read_len = SVN__STREAM_CHUNK_SIZE; + + SVN_ERR(svn_stream_read(stream, read_buf, &read_len)); + if (read_len == 0) + break; + + window_data.data = read_buf; + window_data.len = read_len; - /* ### this is a hack. we should simply read from the stream, construct - ### some windows, and pass those to the handler. there isn't any reason - ### to crank up a full "diff" algorithm just to copy a stream. - ### - ### will fix RSN. */ + delta_op.action_code = svn_txdelta_new; + delta_op.offset = 0; + delta_op.length = read_len; - /* Create a delta stream which converts an *empty* bytestream into the - target bytestream. */ - svn_txdelta(&txstream, svn_stream_empty(pool), stream, pool); - err = svn_txdelta_send_txstream(txstream, handler, handler_baton, pool); + delta_window.tview_len = read_len; + delta_window.num_ops = 1; + delta_window.ops = &delta_op; + delta_window.new_data = &window_data; - if (digest && (! err)) + SVN_ERR(handler(&delta_window, handler_baton)); + + if (digest) + SVN_ERR(svn_checksum_update(md5_checksum_ctx, read_buf, read_len)); + + if (read_len < SVN__STREAM_CHUNK_SIZE) + break; + } + SVN_ERR(handler(NULL, handler_baton)); + + if (digest) { - const unsigned char *result_md5; - result_md5 = svn_txdelta_md5_digest(txstream); - /* Since err is null, result_md5 "cannot" be null. */ - memcpy(digest, result_md5, APR_MD5_DIGESTSIZE); + svn_checksum_t *md5_checksum; + + SVN_ERR(svn_checksum_final(&md5_checksum, md5_checksum_ctx, pool)); + memcpy(digest, md5_checksum->digest, APR_MD5_DIGESTSIZE); } - return err; + return SVN_NO_ERROR; } svn_error_t *svn_txdelta_send_txstream(svn_txdelta_stream_t *txstream, @@ -914,3 +1000,42 @@ svn_error_t *svn_txdelta_send_txstream(svn_txdelta_stream_t *txstream, return SVN_NO_ERROR; } + +svn_error_t * +svn_txdelta_send_contents(const unsigned char *contents, + apr_size_t len, + svn_txdelta_window_handler_t handler, + void *handler_baton, + apr_pool_t *pool) +{ + svn_string_t new_data; + svn_txdelta_op_t op = { svn_txdelta_new, 0, 0 }; + svn_txdelta_window_t window = { 0, 0, 0, 1, 0 }; + window.ops = &op; + window.new_data = &new_data; + + /* send CONTENT as a series of max-sized windows */ + while (len > 0) + { + /* stuff next chunk into the window */ + window.tview_len = len < SVN_DELTA_WINDOW_SIZE + ? len + : SVN_DELTA_WINDOW_SIZE; + op.length = window.tview_len; + new_data.len = window.tview_len; + new_data.data = (const char*)contents; + + /* update remaining */ + contents += window.tview_len; + len -= window.tview_len; + + /* shove it at the handler */ + SVN_ERR((*handler)(&window, handler_baton)); + } + + /* indicate end of stream */ + SVN_ERR((*handler)(NULL, handler_baton)); + + return SVN_NO_ERROR; +} + |