| /* ==================================================================== |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * ==================================================================== |
| */ |
| |
| #include <apr_pools.h> |
| |
| #include "serf.h" |
| #include "serf_bucket_util.h" |
| #include "serf_private.h" |
| |
| typedef struct split_context_t { |
| serf_bucket_t *stream; |
| struct split_stream_ctx_t *head, *tail; |
| |
| bool want_size; |
| } split_context_t; |
| |
| typedef struct split_stream_ctx_t { |
| split_context_t *ctx; |
| |
| apr_size_t read_size; |
| apr_size_t fixed_size; |
| apr_size_t min_size; |
| apr_size_t max_size; |
| apr_uint64_t tail_size; |
| |
| struct split_stream_ctx_t *prev, *next; |
| |
| bool at_eof, cant_read; |
| } split_stream_ctx_t; |
| |
| static void split_detach_head(split_stream_ctx_t *sctx) |
| { |
| split_context_t *ctx = sctx->ctx; |
| |
| if (!ctx || ctx->head != sctx) |
| return; |
| |
| if (ctx->tail != sctx) { |
| /* We can detach now */ |
| ctx->head = sctx->next; |
| sctx->next->prev = NULL; |
| |
| /* Did somebody ask for the size while it wasn't possible? |
| Perhaps we can retrieve and store it now */ |
| if (ctx->want_size) { |
| ctx->want_size = false; |
| ctx->head->tail_size = serf_bucket_get_remaining(ctx->stream); |
| |
| if (ctx->head->tail_size != SERF_LENGTH_UNKNOWN) |
| ctx->head->tail_size -= ctx->head->read_size; |
| } |
| else if (sctx->tail_size != SERF_LENGTH_UNKNOWN) { |
| |
| /* If we have a cached total size, move it to the new head */ |
| ctx->head->tail_size = sctx->tail_size - sctx->read_size |
| + ctx->head->read_size; |
| } |
| } |
| else { |
| serf_bucket_t *stream = ctx->stream; |
| |
| serf_bucket_mem_free(stream->allocator, ctx); |
| serf_bucket_destroy(stream); |
| } |
| |
| sctx->prev = sctx->next = NULL; |
| sctx->ctx = NULL; |
| } |
| |
| static apr_status_t serf_split_read(serf_bucket_t *bucket, |
| apr_size_t requested, |
| const char **data, |
| apr_size_t *len) |
| { |
| split_stream_ctx_t *sctx = bucket->data; |
| split_context_t *ctx = sctx->ctx; |
| apr_status_t status; |
| |
| if (! ctx || sctx->at_eof) { |
| split_detach_head(sctx); |
| *data = NULL; |
| *len = 0; |
| return APR_EOF; |
| } |
| else if (sctx->prev) { |
| /* Not the current head */ |
| *data = NULL; |
| *len = 0; |
| if (sctx->prev->prev || !sctx->prev->at_eof) |
| return APR_EAGAIN; /* Not ready soon */ |
| |
| return APR_SUCCESS; /* Most likely ready at next read */ |
| } |
| |
| if (sctx->max_size != SERF_READ_ALL_AVAIL |
| && requested > (sctx->max_size - sctx->read_size)) |
| { |
| requested = (sctx->max_size - sctx->read_size); |
| } |
| |
| status = serf_bucket_read(ctx->stream, requested, data, len); |
| |
| if (!SERF_BUCKET_READ_ERROR(status)) { |
| sctx->cant_read = (*len != 0); |
| sctx->read_size += *len; |
| |
| if (sctx->min_size != SERF_READ_ALL_AVAIL |
| && sctx->read_size >= sctx->min_size) { |
| /* We read enough. Fix the final length now */ |
| sctx->at_eof = true; |
| sctx->fixed_size = sctx->max_size = sctx->read_size; |
| status = APR_EOF; |
| } |
| else if (APR_STATUS_IS_EOF(status)) { |
| sctx->at_eof = true; |
| |
| if (sctx->fixed_size && sctx->read_size != sctx->fixed_size) { |
| /* We promised more data via get_remaining() than we can |
| deliver. -> BAD get_remaining() */ |
| status = SERF_ERROR_TRUNCATED_STREAM; |
| } |
| else { |
| /* Ok, then this is our size */ |
| sctx->max_size = sctx->fixed_size = sctx->read_size; |
| } |
| } |
| } |
| else |
| sctx->cant_read = false; |
| |
| return status; |
| } |
| |
| static apr_status_t serf_split_read_iovec(serf_bucket_t *bucket, |
| apr_size_t requested, |
| int vecs_size, |
| struct iovec *vecs, |
| int *vecs_used) |
| { |
| split_stream_ctx_t *sctx = bucket->data; |
| split_context_t *ctx = sctx->ctx; |
| apr_status_t status; |
| |
| if (! ctx || sctx->at_eof) { |
| split_detach_head(sctx); |
| *vecs_used = 0; |
| return APR_EOF; |
| } |
| else if (sctx->prev) { |
| /* Not the current head */ |
| *vecs_used = 0; |
| if (sctx->prev->prev || !sctx->prev->at_eof) |
| return APR_EAGAIN; /* Not ready soon */ |
| |
| return APR_SUCCESS; /* Most likely ready at next read */ |
| } |
| |
| if (sctx->max_size != SERF_READ_ALL_AVAIL |
| && requested > (sctx->max_size - sctx->read_size)) |
| { |
| requested = (sctx->max_size - sctx->read_size); |
| } |
| |
| status = serf_bucket_read_iovec(ctx->stream, requested, vecs_size, |
| vecs, vecs_used); |
| |
| if (!SERF_BUCKET_READ_ERROR(status)) { |
| apr_size_t len = 0; |
| int i; |
| |
| for (i = 0; i < *vecs_used; i++) |
| len += vecs[i].iov_len; |
| |
| sctx->cant_read = (len != 0); |
| sctx->read_size += len; |
| |
| if (sctx->min_size != SERF_READ_ALL_AVAIL |
| && sctx->read_size >= sctx->min_size) { |
| /* We read enough. Fix the final length now */ |
| sctx->at_eof = true; |
| sctx->fixed_size = sctx->max_size = sctx->read_size; |
| status = APR_EOF; |
| } |
| else if (APR_STATUS_IS_EOF(status)) { |
| sctx->at_eof = TRUE; |
| |
| if (sctx->fixed_size && sctx->read_size != sctx->fixed_size) { |
| /* We promised more data via get_remaining() than we can |
| deliver. -> BAD get_remaining() */ |
| status = SERF_ERROR_TRUNCATED_STREAM; |
| } |
| else { |
| /* Ok, then this is our size */ |
| sctx->max_size = sctx->fixed_size = sctx->read_size; |
| } |
| } |
| } |
| else |
| sctx->cant_read = false; |
| |
| return status; |
| } |
| |
| static apr_status_t serf_split_peek(serf_bucket_t *bucket, |
| const char **data, |
| apr_size_t *len) |
| { |
| split_stream_ctx_t *sctx = bucket->data; |
| split_context_t *ctx = sctx->ctx; |
| apr_status_t status; |
| |
| if (! ctx || sctx->at_eof) { |
| split_detach_head(sctx); |
| *data = ""; |
| *len = 0; |
| return APR_EOF; |
| } |
| else if (sctx->prev) { |
| /* Not the current head */ |
| *data = ""; |
| *len = 0; |
| if (sctx->prev->prev || !sctx->prev->at_eof) |
| return APR_EAGAIN; /* Not ready soon */ |
| |
| return APR_SUCCESS; /* Most likely ready at next read */ |
| } |
| |
| status = serf_bucket_peek(ctx->stream, data, len); |
| |
| if (!SERF_BUCKET_READ_ERROR(status)) { |
| |
| if (sctx->min_size != SERF_READ_ALL_AVAIL |
| && *len >= (sctx->min_size - sctx->read_size)) { |
| /* We peeked more data than we need to continue |
| to the next bucket. We have to be careful that |
| we don't promise data and not deliver later. |
| */ |
| |
| if (! sctx->fixed_size) { |
| /* Determine the maximum size to what we can deliver now */ |
| sctx->fixed_size = MIN(sctx->max_size, sctx->read_size + *len); |
| sctx->min_size = sctx->max_size = sctx->fixed_size; |
| } |
| |
| *len = sctx->fixed_size - sctx->read_size; |
| status = APR_EOF; |
| } |
| |
| sctx->cant_read = (*len > 0); |
| } |
| else |
| sctx->cant_read = false; |
| |
| return status; |
| } |
| |
| static apr_uint64_t serf_split_get_remaining(serf_bucket_t *bucket) |
| { |
| split_stream_ctx_t *sctx = bucket->data; |
| split_context_t *ctx = sctx->ctx; |
| split_stream_ctx_t *head; |
| apr_uint64_t remaining; |
| |
| if (!ctx || sctx->at_eof) { |
| return 0; /* at eof */ |
| } |
| else if (ctx->head == sctx) { |
| /* We are HEAD. We hereby unlock the data to allow reading the size */ |
| sctx->cant_read = false; |
| } |
| |
| if (sctx->fixed_size) { |
| return sctx->fixed_size - sctx->read_size; /* already calculated */ |
| } |
| |
| /* Do we know the total size? */ |
| head = ctx->head; |
| |
| if (head->tail_size == SERF_LENGTH_UNKNOWN) { |
| if (head->cant_read) { |
| /* Can't obtain the size without unlocking data*/ |
| ctx->want_size = true; |
| |
| return SERF_LENGTH_UNKNOWN; |
| } |
| head->tail_size = serf_bucket_get_remaining(ctx->stream); |
| |
| if (head->tail_size == SERF_LENGTH_UNKNOWN) |
| return SERF_LENGTH_UNKNOWN; |
| |
| /* Add what we already have to avoid updating on every read */ |
| head->tail_size += head->read_size; |
| } |
| |
| remaining = head->tail_size; |
| /* And now we fix the sizes of the buckets until we get to |
| the one we're interested in */ |
| while (head) { |
| |
| if (!head->fixed_size) { |
| /* Size not decided yet. Let's make this chunk as big |
| as allowed */ |
| head->fixed_size = (remaining < head->max_size) |
| ? (apr_size_t)remaining |
| : head->max_size; |
| |
| /* Disable dynamic sizing now */ |
| head->min_size = head->max_size = head->fixed_size; |
| } |
| |
| if (head == sctx) { |
| /* We got the information we need. Exit now to avoid |
| fixing the length of more buckets than needed */ |
| return sctx->fixed_size - sctx->read_size; |
| } |
| |
| remaining -= head->fixed_size; |
| head = head->next; |
| } |
| |
| return SERF_LENGTH_UNKNOWN; /* Hit NULL before our bucket??? */ |
| } |
| |
| static void serf_split_destroy(serf_bucket_t *bucket) |
| { |
| split_stream_ctx_t *sctx = bucket->data; |
| split_context_t *ctx = sctx->ctx; |
| |
| /* Are we the current read bucket */ |
| if (!sctx->prev) { |
| if (!sctx->at_eof && sctx->fixed_size) { |
| /* Auch, we promised to read a specific amount and |
| then didn't keep our promise...*/ |
| serf__bucket_drain(bucket); |
| } |
| |
| split_detach_head(sctx); |
| } |
| else { |
| /* We are destroyed before being read... should never happen, |
| unless the entire chain is destroyed */ |
| |
| split_stream_ctx_t *h = sctx->next; |
| |
| /* We didn't read what we assumed to read. Fix calculations |
| if we can. All data will shift to tail. Let's hope nobody |
| tried to call get_remaining() on the final tail... */ |
| |
| while (h) { |
| h->tail_size = SERF_LENGTH_UNKNOWN; |
| h = h->next; |
| } |
| |
| /* Remove ourself from list */ |
| sctx->prev->next = sctx->next; |
| if (sctx->next) |
| sctx->next->prev = sctx->prev; |
| else |
| ctx->tail = sctx->prev; |
| |
| sctx->ctx = NULL; |
| sctx->prev = sctx->next = NULL; |
| } |
| |
| serf_default_destroy_and_data(bucket); |
| } |
| |
| static apr_status_t serf_split_set_config(serf_bucket_t *bucket, |
| serf_config_t *config) |
| { |
| split_stream_ctx_t *sctx = bucket->data; |
| split_context_t *ctx = sctx->ctx; |
| |
| if (ctx && !sctx->prev) |
| return serf_bucket_set_config(ctx->stream, config); |
| |
| return APR_SUCCESS; |
| } |
| |
| #define SERF_BUCKET_IS__SPLIT(b) SERF_BUCKET_CHECK((b), _split) |
| static const serf_bucket_type_t serf_bucket_type__split = |
| { |
| "SPLIT", |
| serf_split_read, |
| serf_default_readline, |
| serf_split_read_iovec, |
| serf_default_read_for_sendfile, |
| serf_buckets_are_v2, |
| serf_split_peek, |
| serf_split_destroy, |
| serf_default_read_bucket, |
| serf_split_get_remaining, |
| serf_split_set_config |
| }; |
| |
| void serf_bucket_split_create(serf_bucket_t **head, |
| serf_bucket_t **tail, |
| serf_bucket_t *stream, |
| apr_size_t min_chunk_size, |
| apr_size_t max_chunk_size) |
| { |
| split_stream_ctx_t *tail_ctx, *head_ctx; |
| split_context_t *ctx; |
| serf_bucket_alloc_t *allocator = stream->allocator; |
| |
| tail_ctx = serf_bucket_mem_calloc(allocator, sizeof(*tail_ctx)); |
| tail_ctx->tail_size = SERF_LENGTH_UNKNOWN; |
| |
| if (SERF_BUCKET_IS__SPLIT(stream)) { |
| head_ctx = stream->data; |
| ctx = head_ctx->ctx; |
| *head = stream; |
| |
| head_ctx = tail_ctx->prev = ctx->tail; |
| ctx->tail->next = tail_ctx; |
| ctx->tail = tail_ctx; |
| } |
| else { |
| ctx = serf_bucket_mem_calloc(allocator, sizeof(*ctx)); |
| ctx->stream = stream; |
| |
| head_ctx = serf_bucket_mem_calloc(allocator, sizeof(*head_ctx)); |
| head_ctx->ctx = ctx; |
| head_ctx->tail_size = SERF_LENGTH_UNKNOWN; |
| |
| ctx->tail = head_ctx->next = tail_ctx; |
| ctx->head = tail_ctx->prev = head_ctx; |
| |
| *head = serf_bucket_create(&serf_bucket_type__split, allocator, |
| head_ctx); |
| } |
| |
| *tail = serf_bucket_create(&serf_bucket_type__split, allocator, tail_ctx); |
| |
| tail_ctx->ctx = ctx; |
| head_ctx->fixed_size = 0; /* Not fixed yet. This might change an existing |
| tail bucket that we received as stream! */ |
| head_ctx->min_size = MAX(1, min_chunk_size); |
| head_ctx->max_size = MAX(head_ctx->min_size, max_chunk_size); |
| |
| /* tail_ctx->fixed_size = 0; // Unknown */ |
| tail_ctx->min_size = SERF_READ_ALL_AVAIL; |
| tail_ctx->max_size = SERF_READ_ALL_AVAIL; |
| } |