use function name prefixes instead of paths

where that makes sense

and add some more words on hash table case sensitivity

Data-structure-survey.md

@@ -47,13 +47,13 @@ fair chance this will become a historical document rather than being
 maintained as a current one.
 
 
-# `isc/astack`
+# `isc_astack`
 
 Fixed-size array stack
 
 ## used by
 
-  * `isc/netmgr/netmgr` for object caches
+  * `netmgr` for object caches
 
 ## notes
 
@@ -65,25 +65,25 @@ Will be gone after the netmgr refactoring and replaced with per-thread object
 pools/lists
 
 
-# `isc/heap`
+# `isc_heap`
 
 Priority queue
 
 ## used by
 
-  * `dns/rbtdb` to find nodes by TTL; there are multiple heaps split
+  * `dns_rbtdb` to find nodes by TTL; there are multiple heaps split
     based on node->locknum like a few other parts of rbtdb.
 
-  * `dns/zoneverify` for checking consistency of NSEC3 chains.
+  * `dns_zoneverify` for checking consistency of NSEC3 chains.
 
-  * `isc/timer`, the canonical use for a heap.
+  * `isc_timer`, the canonical use for a heap.
 
 ## notes
 
 Single-threaded.
 
 There's a min-heap in libuv, implemented as a binary tree. The
-standard algorithms (as in `isc/heap`) use an array which should have
+standard algorithms (as in `isc_heap`) use an array which should have
 better performance.
 
 ## Ondřej's notes
@@ -91,7 +91,7 @@ better performance.
 The usage in isc_timer has been removed in the loopmgr branch
 
 
-# `isc/ht`
+# `isc_ht`
 
 Hash table
 
@@ -100,10 +100,10 @@ Hash table
   * `bin/plugins/filter-a` and `bin/plugins/filter-aaaa` for finding
     the filter state given a `query_ctx_t` pointer. (case-sensitive)
 
-  * `dns/adb` for looking up nameservers by name (case-insensitive) or
+  * `dns_adb` for looking up nameservers by name (case-insensitive) or
     by address (case-insensitive???).
 
-  * `dns/catz` (which leaks into `bin/named/server`) for the list of
+  * `dns_catz` (which leaks into `bin/named/server`) for the list of
     catalog zones in a view, and the entries in a catalog zone.
     These hash tables are unexpectedly case-sensitive.
 
@@ -117,23 +117,27 @@ Hash table
     `catalog-zones{}` clause does not matter. Initializing the hash table as
     case-insensitive is not enough to fix this bug.
 
-  * `dns/rpz` in the zone update functions, case-sensitive but the domain
+  * `dns_rpz` in the zone update functions, case-sensitive but the domain
     names are forced to lower case.
 
-  * `isc/tls` for TLS context caches. (case-sensitive)
+  * `isc_tls` for TLS context caches. (case-sensitive)
 
 ## notes
 
 Single-threaded.
 
-Case-sensitive and case-insensitive variants, chosen at run-time.
+Case-sensitive and case-insensitive variants, chosen at run-time. The
+case-insensitive `isc_hash` functions squash the input to lower case before
+hasing, instead of using a specialized single-pass case-insensitive hash. It
+would be simpler to make the callers handle case-insensitivity since there
+are so few of them.
 
 Uses chaining, so it is heavy on indirection and heavy on allocation.
 Modern hash tables use open addressing.
 
 ## Ondřej's notes
 
-There's work to do on `isc/ht`:
+There's work to do on `isc_ht`:
 
  1. make header-only variant of the hashtable, so we can unify the usage
     across the codebase (e.g. no extra allocations when storing item)
@@ -144,17 +148,17 @@ There's work to do on `isc/ht`:
  3. the resizing was added only recently, we still miss shrinking (should be
     easy enough to do)
 
-`dns/adb` was recently refactored, it used a custom hashtable before
+`dns_adb` was recently refactored, it used a custom hashtable before
 
 
-# `isc/radix`
+# `isc_radix`
 
 Radix tree for IP address prefix matching
 
 ## used by
 
-  * `dns/acl`
-  * `dns/iptable`
+  * `dns_acl`
+  * `dns_iptable`
 
 ## notes
 
@@ -172,7 +176,7 @@ Uses reserved identifiers for static functions, which is undefined
 behaviour.
 
 
-# `isc/symtab`
+# `isc_symtab`
 
 Another hash table, with another hash function.
 
@@ -186,7 +190,7 @@ Another hash table, with another hash function.
 Single-threaded.
 
 Ought to be unnecessary. Might be worth cleaning up as part of some
-general parser refactoring (`isc/lex` could probably be made faster
+general parser refactoring (`isc_lex` could probably be made faster
 using `re2c`).
 
 ## Ondřej's notes