6 * Added companion library <<../ucw-json/index:,LibUCW-JSON>> for parsing
8 * Fastbufs have a new wrapper for parsing and generating hex-dumps.
9 Useful primarily for debugging.
10 * Unicode functions are now more strict and they reject denormalized
11 UTF-8 sequences. Also, it is now possible to append UTF-8 characters
13 * The naming of memory pool functions mp_append_printf() and mp_append_vprintf()
14 turned out to be unfortunate as they have differently from all other functions
15 operating on growing buffers. They have been renamed to mp_printf_append()
16 and mp_vprintf_append() with the old names kept as aliases for backward
21 * Fixed several minor bugs in the <<mainloop:,mainloop>> module.
25 * Cleaned up and documented the <<../ucw-xml/index:,LibUCW-XML>> companion
26 library -- a lightning fast standards-complient XML parser.
27 * Solved problems with closing of stderr in daemons: see the new function
28 <<log:log_drop_stderr()>>.
32 * Fixed race conditions in <<daemon:,daemon helpers>>.
33 * The <<xtypes:,extended types>> have been documented and integrated
34 in the table printer, command-line option parser, and configuration parser.
35 * The <<ucw-tableprinter.5:,table printer options>> have been documented.
42 * Major changes of the table printer module. Finally, its interface can be
43 considered stable now.
47 * The <<opt:,command-line option parser>> gained `OPT_BREAK` class and
48 `OPT_HELP_COLUMNS` flag.
49 * The strtonum module supports more types.
56 * *Incompatible:* It turned out that almost all users of the <<gary:,growing array>>
57 module push/pop individual elements. Therefore, we have removed the second
58 argument (item count) of `GARY_PUSH` and `GARY_POP`. If you want to push/pop
59 multiple elements at once, use `GARY_PUSH_MULTI` and `GARY_POP_MULTI`.
60 * *Incompatible:* The interface of the <<heap:,heap>> module was cleaned up
61 to remove non-systematic side-effects. The `HEAP_INSERT` operation is now
62 a proper insert (previously, it was just cleanup after insertion performed
63 by the caller), similarly `HEAP_INCREASE` and `HEAP_DECREASE`. The `HEAP_DELMIN`
64 operation was renamed to `HEAP_DELETE_MIN`. New operations `HEAP_REPLACE` and
65 `HEAP_REPLACE_MIN` have been added. If you need to track positions of elements
66 in the heap, please check the notes at individual functions.
67 * The <<conf:,configuration file parser>> has been improved:
68 ** Multiple instances of the configuration parser are supported.
69 ** *Incompatible:* As there may be more instances, we can no longer use
70 global variables to control the configuration system. In particular,
71 `cf_need_journal` and `cf_pool` variables have been replaced by
72 functions <<conf:cf_set_journalling()>> and <<conf:cf_get_pool()>>.
73 ** *Incompatible:* Loading of configuration files has been decoupled from
74 the getopt wrapper, so you might need to include `conf.h` for functions
75 which were previously declared in `getopt.h`.
76 ** New functions have been added:
77 <<conf:cf_open_group()>>, <<conf:cf_close_group()>>, and <<conf:cf_revert()>>.
78 ** *Incompatible:* Dynamic configuration arrays have been re-implemented in
79 terms of our generic <<gary:,growing arrays>>. This makes them easier to
80 use and most of the interface has been preserved. The only exception is
81 static allocation via the DARY_ALLOC() macro, which is no longer available.
82 * *Incompatible:* The `UCW::CGI` Perl module has its custom error handlers
83 (which override default Perl error handlers) split off to a separate module
84 `UCW::CGI::ErrorHandler`.
88 * <<daemon:,Daemon helpers>> have been added including a new `daemon-control`
89 utility. The old `daemon-helper` utility has been obsoleted and it is not
91 * <<signal:,Signal helpers>> for translation between signal names and numbers
93 * The fastbuf I/O layer received a new back-end <<fastbuf:fbmulti,fb_multi>>,
94 which concatenates several fastbuf streams to form a single virtual stream.
95 * Added <<varint:,varint>> module for efficient UTF-8-like encoding of 64-bit
96 integers to byte sequences.
97 * Added <<table:,table printer>> module for configurable formatting of
98 2-dimensional tables in both user-friendly and machine-friendly ways.
99 * A <<opt:,parser of command-line options>> has been added, similar in spirit to
100 our <<conf:,configuration file parser>>. The <<conf:getopt_h,getopt>> module
102 * <<alloc:,Generic allocators>> have been introduced, providing an abstract
103 way of memory allocation. <<gary:,Growing arrays>> are now based on such
104 allocators, which allows for example growing arrays in memory pools.
108 * Libucw finally has a clean ABI, which does not pollute namespace, risking
109 collisions with other libraries. However, we did not want to abandon our
110 nicely and simply named functions, so the header files define macros,
111 which translate names of all externally visible symbols to start with `ucw_`.
112 If you don't like this, configure libucw with `CONFIG_UCW_CLEAN_ABI` turned off.
113 * All helper utilities are now installed with names starting with `ucw-` to
115 * The auxiliary libraries have been renamed to `libucw-charset`, `libucw-images`,
116 `libucw-xml`. The clean ABI promise does not extend to them yet.
117 * The alias `uns` for `unsigned int` has been replaced by a more common `uint`.
118 The old name is still maintained for backward compatibility.
119 * Several functions now accept `size_t` instead of `unsigned int` for size arguments.
123 * `<stdbool.h>` is automatically included by `<ucw/lib.h>`.
128 * *Incompatible:* The `timestamp_t` type has been decoupled from wall clock time.
129 It now specifies the number of milliseconds from an unspecified origin, so that
130 it can for example refer to the system monotonic clock. The `ucw_time_t` type
133 * The <<mainloop:,mainloop>> module has been rewritten:
134 ** Multiple instances of the main loop are supported (to be used in different
135 threads or locally within a library function).
136 ** The new implementation is more efficient: it uses heaps for timers,
137 epoll() for file descriptors (when available).
138 ** The return value of <<mainloop:struct_main_file,`main_file`>> handlers has been
139 changed to <<mainloop:enum_main_hook_return,`HOOK_IDLE`>> and <<mainloop:enum_main_hook_return,`HOOK_RETRY`>>.
140 However, the numerical values are equal, so old code should keep working.
141 ** *Incompatible:* The main loop time (`main_now`) has been decoupled from wall clock time
142 and moved to a field in the `main_context` structure. It can be accessed either directly
143 or via <<mainloop:main_get_now()>>. The `main_now_seconds` variable has
144 been removed, `main_idle_time` has become a structure field.
145 ** *Incompatible:* The interface for asynchronous reading and writing
146 (file_read() and friends) has been separated from the core of the main loop.
147 Use <<mainloop:struct_main_block_io,`struct main_block_io`>> and related functions instead.
148 ** *Incompatible:* file_close_all() is gone. You have to call <<mainloop:main_teardown()>>
149 or <<mainloop:main_destroy()>> to clean up properly after fork().
150 ** Added support for <<mainloop:signal,synchronous delivery of signals>>.
151 ** Added relative timers: <<mainloop:timer_add_rel()>>.
152 ** Modification of events from a running event handler is always safe.
153 ** Deleting an already deleted event is always safe.
154 ** For any event type, it is possible to ask whether it is active (added to the mainloop) or not: <<mainloop:hook_is_active()>> and friends.
155 ** A new mainloop front-end for asynchronous <<mainloop:recordio,record-based I/O>> has been added.
157 * Added support for <<trans:,resource pools and transactions>>, which is a general
158 mechanism for tracking resources and reporting errors. It is still considered
159 experimental, so the API can change in future releases.
161 * Added a <<gary:,growing array>> module `gary.h`, similar to `gbuf.h`, but with
162 a much more convenient interface.
164 * The <<lists:,Circular linked lists>> can recognize unlinked nodes,
165 see <<lists:clist_unlink()>>.
167 * Added `strtonum.h` -- a module for precise parsing of numbers.
169 * When compiled by a recent enough GCC, `__thread` is used for thread-local variables,
170 which is more efficient than the POSIX per-thread storage.
171 ** *Incompatible:* `ucwlib_context->thread_id` is no longer available directly,
172 please use <<thread:ucwlib_thread_id()>> instead.
174 * *Incompatible:* Several modules have been declared obsolete and removed:
175 ** `sighandler` -- generic signal handling (it still exists internally)
176 ** `qache` -- a mmap-based shared cache
177 ** `prefetch` -- an interface to memory prefetch instructions; superseded by GCC `__builtin_prefetch`
178 ** `randomkey` -- a generator of cryptographically strong pseudo-random tokens; will be replaced
179 by something more generic soon
180 ** `profile` -- a profiling hack
182 * *Incompatible:* Several modules now have their own header files:
183 ** `process.h` -- all functions related to processes, previously declared in `lib.h`
184 ** `io.h` -- functions related to files from `lib.h` and `lfs.h`
185 ** `time.h` -- timestamps and interval timers, previously in `lib.h`
187 * *Incompatible:* Several configuration options were renamed or removed:
188 ** `CONFIG_FAKE_ELTPOOL` → `CONFIG_UCW_FAKE_ELTPOOL`
189 ** `CONFIG_LARGE_FILES` → `CONFIG_UCW_LARGE_FILES`
190 ** `CONFIG_OWN_GETOPT` → `CONFIG_UCW_OWN_GETOPT`
191 ** `CONFIG_DIRECT_IO` → `CONFIG_UCW_DIRECT_IO`
192 ** `DEFAULT_CONFIG` → `CONFIG_UCW_DEFAULT_CONFIG`
193 ** `ENV_VAR_CONFIG` → `CONFIG_UCW_ENV_VAR_CONFIG`
194 ** `CONFIG_LFS` was removed
195 ** `CONFIG_URL_ESCAPE_COMPAT` was removed
197 * `UCW::Configure` supports running of test programs.
199 * `UCW::CGI` support multiple argument tables and UTF-8 mode. Also, it uses the
200 proper HTTP status codes when reporting errors.
202 * Implementation details of <<fastbuf:,fastbufs>> have changed. The new code checks
203 invariants more carefully, so it is possible that custom fastbuf back-ends which
204 are buggy now fail, although they previously seemed to work.
209 This was the first stand-alone release of LibUCW. Before that, LibUCW was developed
210 as a part of the http://www.ucw.cz/holmes/[Sherlock Holmes project].