mod_substitute: No real functional change, but: - define default for maximum line length indepenent of MAX_STRING_LEN - Clarify line length check with a comment - add supported 'b' suffix to directive description

mod_substitute: Restrict configuration in .htaccess to FileInfo as documented.

mod_substitute: Make maximum line length configurable.

mod_substitute: Fix memory limitation in case of regexp plus flatten. The maxlen argument of ap_varbuf_regsub() is unsigned. Passing in "AP_SUBST_MAX_LINE_LENGTH - vb.strlen" in case vb.strlen got to big didn't result in the expected error but instead was handled as a very big maxlen.

Strip useless apr_brigade_cleanup() calls.

Add lots of unique tags to error log messages

Fix up some length limit calculation

Add some comments and another line length check

Also do length check if the last line is not LF terminated

re-add apr_pool_clear accidentally removed in r1197405

To prevent overboarding memory usage, limit line length to 1MB

Improve handling of maxlen = APR_SIZE_MAX, noticed by Jim. Use apr_pregsub_ex() and maxlen = 0 for unlimited in mod_substitute.

Limit ap_pregsub() to 64K, add ap_pregsub_ex() for longer strings and with better error reporting. Modify ap_varbuf_regsub() to be similar to ap_pregsub_ex().

Make mod_substitute more efficient: - Use varbuf resizable buffer instead of constantly allocating pool memory and copying data around. This changes the memory requirement from quadratic in ((number of substitutions in line) * (length of line)) to linear in (length of line). - Instead of copying buckets just to append a \0, use new ap_regexec_len() function PR: 50559

Cleanup effort in prep for GA push: Trim trailing whitespace... no func change

Use the new APLOG_USE_MODULE/AP_DECLARE_MODULE macros everywhere to take advantage of per-module loglevels

* Fix a memory leak by freeing the memory consumed by the bucket. PR: 44948 Submitted by: Dan Poirier <poirier pobox.com> Reviewed by: rpluem

* APR_BUCKET_NEXT is wrong here as we are already a doing a APR_BUCKET_NEXT in the for loop and this causes us to jump *two* buckets forward. This can cause us to jump over the Sentinel of the brigade and thus causes an endless loop.

* Fix potential segfault if flags remains NULL.

* Allow empty substitute patterns (to remove data from the stream), but disallow empty search patterns.

In the case where we have only 1 pattern, then we can safely be quick, no matter what.

Change default of mod_substitute to flattening... Via current discussion on dev@httpd

* s/MAX_BUCKETS/AP_MAX_BUCKETS/ to avoid namespace conflicts as pointed out by jim. No functional change.

* Optimize memory behaviour of mod_substitute by * Precreate all needed brigades, save them in the filter context and reuse them in order to avoid frequent recreations using the request pool. * Use a temporary pool for all the needed copy stuff and clean it up every time we passed the passbb brigade down the chain. We can pass the brigade down the chain directly after we processed one bucket from the original brigade as buffering is done by the network filters. * Use transient instead of pool buckets. * There are cases that lead to the exceptional situation of a very large passbb bucket brigade (about 1,000,000 buckets) as a result of processing 4 MB of a file. So I add a flush bucket once I have more than MAX_BUCKET (1000) buckets in the brigade and pass it down the chain to get it send and the passbb bucket brigade cleaned up and its memory reusable again.

move mod_substitute from exp to filters