This commit backs out certain optimizations around setting environment
variables, and replaces them with move semantics. env_set accepts a
list, by value, permitting callers to use std::move to transfer
ownership.
Commit f872f25f introduced a freed memory access regression on line 460
of env.cpp, where an environment variable was converted to a temporary
string, the .c_str() address of which was stored while the string
temporary was destroyed.
This commit keeps a reference to the original string lying around so
that the c_str() pointer does not point to freed memory.
Valgrind warns that the sometimes uninitialized sigaction.sa_flags field
is sometimes used when passed to the signal handler.
This patch explicitly zeros out the sigaction.sa_flags field at creation
time.
cherry-picked from krader1961/fish-shell commit b69df4fe72
Fixes#4353 (regression in indexing of history contents) and introduces
new unit tests to catch bad $history indexing in the future.
Using bare vars is more efficient because it makes the builtin `math`
expression cache more useful. That's because if you prefix each var with
a dollar-sign then the fish parser expands it before `math` is run.
Something like `math x + 1` can be cached since the expression is the
same each time it is run. But if you do `math $x + 1` and x==1 then you're
effectively executing `math 1 + 1`. And if x==2 the next time then you're
running `math 2 + 1`. Which makes the expression cache much less effective.
This implements an LRU cache of recently seen math expressions. When
executing math inside loops and the like this can provide a 33% decrease
in the time to execute the `math` command.
Remove our `math` function that wraps `bc`. Our math builtin is now good
enough that it can be the default implementation.
Another step in resolving #3157.
We need our `math` builtin to behave like `bc` with respect to rounding
floating point values to integer to avoid breaking to many existing
uses. So when scale is zero round down to the nearest integer.
Another change for #3157.
The MuParser supports the concept of multiple expressions separated by
commas. This implements support for that so that you can do things like
this:
set results (math '1+1, 4*2, 9^2')
This is the second baby step in resolving #3157. Implement a bare minimum
builtin `math` command. This is solely to ensure that fish can be built
and run in the Travis build environments. This is okay since anyone running
`builtin math` today is already getting an error response.
Also, more work is needed to support bare var references, multiple result
values, etc.
First step in fixing issue #3157 is to check-in the source code and hook
it into our build system.
The inclusion of the MuParser source adds the MIT License to those that
apply to fish. Update our documentation to reflect that fact.
The MuParser documentation is at
http://beltoforion.de/article.php?a=muparser. The source was downloaded
from https://github.com/beltoforion/muparser/releases. It is also hosted
on Github, https://github.com/beltoforion/muparser/. I did not download
it from Github because that source contained just a couple of cleanup
changes which don't affect its behavior.
Using a read-only variable like `status` as a for loop control variable
has never worked. But without this change you simply get non-sensical
behavior that leaves you scratching your head in puzzlement. This change
replaces the non-sensical behavior with an explicit error message.
Fixes#4342
Recent changes to switch to unordered sets/maps can cause the order in
which items are returned to be non-deterministic. This change ensures
that the argparse "Mutually exclusive flags" error message to be
deterministic with respect to the order of the interpolated values.
Make setting fish vars more efficient by avoiding creating a
wcstring_list_t for the case where we're setting one value. For the case
where we're passing a list of values swap it with the list in the var
rather than copying it. This makes the benchmark in #4200 approximately
6% faster.
Since we are including XXHash32/64 anyway for the wchar_t* hashing,
we might as well use it.
Use arch-specific hash size and xxhash for all wcstring hashing
Instead of using XXHash64 for all platforms, use the 32-bit version
when running on 32-bit platforms where XXHash64 is significantly slower
than XXHash32 (and the additional precision will not be used).
Additionally, manually specify wcstring_hash as hashing method for
non-const wcstring unordered_set/map instances (the const varieties
don't have an in-library hash and so already use our xxhash-based
specialization when calling std::hash<const wcstring>).
commit 50f414a45d58fcab664ff662dd27befcfa0fdd95
Author: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat Aug 19 13:43:35 2017 -0500
Converted file_id_t set to unordered_set with custom hash
commit 83ef2dd7cc1bc3e4fdf0b2d3546d6811326cc3c9
Author: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat Aug 19 13:43:14 2017 -0500
Converted remaining set<wcstring> to unordered_set<wcstring>
commit 053da88f933f27505b3cf4810402e2a2be070203
Author: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat Aug 19 13:29:21 2017 -0500
Switched function sets to unordered_set
commit d469742a14ac99599022a9258cda8255178826b5
Author: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat Aug 19 13:21:32 2017 -0500
Converted list of modified variables to an unordered set
commit 5c06f866beeafb23878b1a932c7cd2558412c283
Author: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat Aug 19 13:15:20 2017 -0500
Convert const_string_set_t to std::unordered_set
As it is a readonly-list of raw character pointer strings (not
wcstring), this necessitated the addition of a hashing function since
the C++ standard library does not come with a char pointer hash
function.
To that end, a zlib-licensed [0] port of the excellent, lightweight
XXHash family of 32- and 64-bit hashing algorithms in the form of a C++
header-only include library has been included. XXHash32/64 is pretty
much universally the fastest hashing library for general purpose
applications, and has been thoroughly vetted and is used in countless
open source projects. The single-header version of this library makes it
a lot simpler to include in the fish project, and the license
compatibility with fish' GPLv2 and the zero-lib nature should make it an
easy decision.
std::unordered_set brings a massive speedup as compared to the default
std::set, and the further use of the fast XXHash library to provide the
string hashing should make all forms of string lookups in fish
significantly faster (to a user-noticeable extent).
0: http://create.stephan-brumme.com/about.html
commit 30d7710be8f0c23a4d42f7e713fcb7850f99036e
Author: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat Aug 19 12:29:39 2017 -0500
Using std::unordered_set for completions backing store
While the completions shown to the user are sorted, their storage in
memory does not need to be since they are re-sorted before they are
shown in completions.cpp.
commit 695e83331d7a60ba188e57f6ea0d9b6da54860c6
Author: Mahmoud Al-Qudsi <mqudsi@neosmart.net>
Date: Sat Aug 19 12:06:53 2017 -0500
Updated is_loading to use unordered_set
Per the discussion with @faho in #4332, replaced some custom completion
state detection functions with standard __fish_* functions used in other
completion sources.
(cherry picked from commit f706081ea4)
No longer auto-generated. Everything has been summarized. Supressing
file completions for initial command, providing list of valid initial
commands, filtering --options by subcommand.
(cherry picked from commit 539acd9fc5)
No longer using RAII wrappers around pthread_mutex_t and pthread_cond_t
in favor of the C++11 std::mutex, std::recursive_mutex, and
std::condition_variable data types.
The `react_to_variable_change()` function is called whenever a fish var
is set. Even as a consequence of statements like `for x in a b c`. It is
therefore critical that that function be as fast as possible. Especially
when setting the var doesn't have any side-effects which is true something
like 99.9999% of the time.
This change reduces the overhead of `react_to_variable_change()` to
unmeasurable levels. Making the synthetic benchmark in issue #4341
36% faster.
Fixes#4341
Internally fish should store vars as a vector of elements. The current
flat string representation is a holdover from when the code was written
in C.
Fixes#4200
