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.gitignore
vendored
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19
.gitignore
vendored
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|||
*.go
|
||||
Makefile.in
|
||||
Makefile
|
||||
aclocal.m4
|
||||
autom4te.cache
|
||||
config.log
|
||||
config.status
|
||||
configure
|
||||
|
||||
build-aux/install-sh
|
||||
build-aux/missing
|
||||
|
||||
*.log
|
||||
tests/*.log
|
||||
tests/*.trs
|
||||
|
||||
pre-inst-env
|
||||
|
||||
.local.envrc
|
674
COPYING
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674
COPYING
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@ -0,0 +1,674 @@
|
|||
GNU GENERAL PUBLIC LICENSE
|
||||
Version 3, 29 June 2007
|
||||
|
||||
Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
|
||||
Everyone is permitted to copy and distribute verbatim copies
|
||||
of this license document, but changing it is not allowed.
|
||||
|
||||
Preamble
|
||||
|
||||
The GNU General Public License is a free, copyleft license for
|
||||
software and other kinds of works.
|
||||
|
||||
The licenses for most software and other practical works are designed
|
||||
to take away your freedom to share and change the works. By contrast,
|
||||
the GNU General Public License is intended to guarantee your freedom to
|
||||
share and change all versions of a program--to make sure it remains free
|
||||
software for all its users. We, the Free Software Foundation, use the
|
||||
GNU General Public License for most of our software; it applies also to
|
||||
any other work released this way by its authors. You can apply it to
|
||||
your programs, too.
|
||||
|
||||
When we speak of free software, we are referring to freedom, not
|
||||
price. Our General Public Licenses are designed to make sure that you
|
||||
have the freedom to distribute copies of free software (and charge for
|
||||
them if you wish), that you receive source code or can get it if you
|
||||
want it, that you can change the software or use pieces of it in new
|
||||
free programs, and that you know you can do these things.
|
||||
|
||||
To protect your rights, we need to prevent others from denying you
|
||||
these rights or asking you to surrender the rights. Therefore, you have
|
||||
certain responsibilities if you distribute copies of the software, or if
|
||||
you modify it: responsibilities to respect the freedom of others.
|
||||
|
||||
For example, if you distribute copies of such a program, whether
|
||||
gratis or for a fee, you must pass on to the recipients the same
|
||||
freedoms that you received. You must make sure that they, too, receive
|
||||
or can get the source code. And you must show them these terms so they
|
||||
know their rights.
|
||||
|
||||
Developers that use the GNU GPL protect your rights with two steps:
|
||||
(1) assert copyright on the software, and (2) offer you this License
|
||||
giving you legal permission to copy, distribute and/or modify it.
|
||||
|
||||
For the developers' and authors' protection, the GPL clearly explains
|
||||
that there is no warranty for this free software. For both users' and
|
||||
authors' sake, the GPL requires that modified versions be marked as
|
||||
changed, so that their problems will not be attributed erroneously to
|
||||
authors of previous versions.
|
||||
|
||||
Some devices are designed to deny users access to install or run
|
||||
modified versions of the software inside them, although the manufacturer
|
||||
can do so. This is fundamentally incompatible with the aim of
|
||||
protecting users' freedom to change the software. The systematic
|
||||
pattern of such abuse occurs in the area of products for individuals to
|
||||
use, which is precisely where it is most unacceptable. Therefore, we
|
||||
have designed this version of the GPL to prohibit the practice for those
|
||||
products. If such problems arise substantially in other domains, we
|
||||
stand ready to extend this provision to those domains in future versions
|
||||
of the GPL, as needed to protect the freedom of users.
|
||||
|
||||
Finally, every program is threatened constantly by software patents.
|
||||
States should not allow patents to restrict development and use of
|
||||
software on general-purpose computers, but in those that do, we wish to
|
||||
avoid the special danger that patents applied to a free program could
|
||||
make it effectively proprietary. To prevent this, the GPL assures that
|
||||
patents cannot be used to render the program non-free.
|
||||
|
||||
The precise terms and conditions for copying, distribution and
|
||||
modification follow.
|
||||
|
||||
TERMS AND CONDITIONS
|
||||
|
||||
0. Definitions.
|
||||
|
||||
"This License" refers to version 3 of the GNU General Public License.
|
||||
|
||||
"Copyright" also means copyright-like laws that apply to other kinds of
|
||||
works, such as semiconductor masks.
|
||||
|
||||
"The Program" refers to any copyrightable work licensed under this
|
||||
License. Each licensee is addressed as "you". "Licensees" and
|
||||
"recipients" may be individuals or organizations.
|
||||
|
||||
To "modify" a work means to copy from or adapt all or part of the work
|
||||
in a fashion requiring copyright permission, other than the making of an
|
||||
exact copy. The resulting work is called a "modified version" of the
|
||||
earlier work or a work "based on" the earlier work.
|
||||
|
||||
A "covered work" means either the unmodified Program or a work based
|
||||
on the Program.
|
||||
|
||||
To "propagate" a work means to do anything with it that, without
|
||||
permission, would make you directly or secondarily liable for
|
||||
infringement under applicable copyright law, except executing it on a
|
||||
computer or modifying a private copy. Propagation includes copying,
|
||||
distribution (with or without modification), making available to the
|
||||
public, and in some countries other activities as well.
|
||||
|
||||
To "convey" a work means any kind of propagation that enables other
|
||||
parties to make or receive copies. Mere interaction with a user through
|
||||
a computer network, with no transfer of a copy, is not conveying.
|
||||
|
||||
An interactive user interface displays "Appropriate Legal Notices"
|
||||
to the extent that it includes a convenient and prominently visible
|
||||
feature that (1) displays an appropriate copyright notice, and (2)
|
||||
tells the user that there is no warranty for the work (except to the
|
||||
extent that warranties are provided), that licensees may convey the
|
||||
work under this License, and how to view a copy of this License. If
|
||||
the interface presents a list of user commands or options, such as a
|
||||
menu, a prominent item in the list meets this criterion.
|
||||
|
||||
1. Source Code.
|
||||
|
||||
The "source code" for a work means the preferred form of the work
|
||||
for making modifications to it. "Object code" means any non-source
|
||||
form of a work.
|
||||
|
||||
A "Standard Interface" means an interface that either is an official
|
||||
standard defined by a recognized standards body, or, in the case of
|
||||
interfaces specified for a particular programming language, one that
|
||||
is widely used among developers working in that language.
|
||||
|
||||
The "System Libraries" of an executable work include anything, other
|
||||
than the work as a whole, that (a) is included in the normal form of
|
||||
packaging a Major Component, but which is not part of that Major
|
||||
Component, and (b) serves only to enable use of the work with that
|
||||
Major Component, or to implement a Standard Interface for which an
|
||||
implementation is available to the public in source code form. A
|
||||
"Major Component", in this context, means a major essential component
|
||||
(kernel, window system, and so on) of the specific operating system
|
||||
(if any) on which the executable work runs, or a compiler used to
|
||||
produce the work, or an object code interpreter used to run it.
|
||||
|
||||
The "Corresponding Source" for a work in object code form means all
|
||||
the source code needed to generate, install, and (for an executable
|
||||
work) run the object code and to modify the work, including scripts to
|
||||
control those activities. However, it does not include the work's
|
||||
System Libraries, or general-purpose tools or generally available free
|
||||
programs which are used unmodified in performing those activities but
|
||||
which are not part of the work. For example, Corresponding Source
|
||||
includes interface definition files associated with source files for
|
||||
the work, and the source code for shared libraries and dynamically
|
||||
linked subprograms that the work is specifically designed to require,
|
||||
such as by intimate data communication or control flow between those
|
||||
subprograms and other parts of the work.
|
||||
|
||||
The Corresponding Source need not include anything that users
|
||||
can regenerate automatically from other parts of the Corresponding
|
||||
Source.
|
||||
|
||||
The Corresponding Source for a work in source code form is that
|
||||
same work.
|
||||
|
||||
2. Basic Permissions.
|
||||
|
||||
All rights granted under this License are granted for the term of
|
||||
copyright on the Program, and are irrevocable provided the stated
|
||||
conditions are met. This License explicitly affirms your unlimited
|
||||
permission to run the unmodified Program. The output from running a
|
||||
covered work is covered by this License only if the output, given its
|
||||
content, constitutes a covered work. This License acknowledges your
|
||||
rights of fair use or other equivalent, as provided by copyright law.
|
||||
|
||||
You may make, run and propagate covered works that you do not
|
||||
convey, without conditions so long as your license otherwise remains
|
||||
in force. You may convey covered works to others for the sole purpose
|
||||
of having them make modifications exclusively for you, or provide you
|
||||
with facilities for running those works, provided that you comply with
|
||||
the terms of this License in conveying all material for which you do
|
||||
not control copyright. Those thus making or running the covered works
|
||||
for you must do so exclusively on your behalf, under your direction
|
||||
and control, on terms that prohibit them from making any copies of
|
||||
your copyrighted material outside their relationship with you.
|
||||
|
||||
Conveying under any other circumstances is permitted solely under
|
||||
the conditions stated below. Sublicensing is not allowed; section 10
|
||||
makes it unnecessary.
|
||||
|
||||
3. Protecting Users' Legal Rights From Anti-Circumvention Law.
|
||||
|
||||
No covered work shall be deemed part of an effective technological
|
||||
measure under any applicable law fulfilling obligations under article
|
||||
11 of the WIPO copyright treaty adopted on 20 December 1996, or
|
||||
similar laws prohibiting or restricting circumvention of such
|
||||
measures.
|
||||
|
||||
When you convey a covered work, you waive any legal power to forbid
|
||||
circumvention of technological measures to the extent such circumvention
|
||||
is effected by exercising rights under this License with respect to
|
||||
the covered work, and you disclaim any intention to limit operation or
|
||||
modification of the work as a means of enforcing, against the work's
|
||||
users, your or third parties' legal rights to forbid circumvention of
|
||||
technological measures.
|
||||
|
||||
4. Conveying Verbatim Copies.
|
||||
|
||||
You may convey verbatim copies of the Program's source code as you
|
||||
receive it, in any medium, provided that you conspicuously and
|
||||
appropriately publish on each copy an appropriate copyright notice;
|
||||
keep intact all notices stating that this License and any
|
||||
non-permissive terms added in accord with section 7 apply to the code;
|
||||
keep intact all notices of the absence of any warranty; and give all
|
||||
recipients a copy of this License along with the Program.
|
||||
|
||||
You may charge any price or no price for each copy that you convey,
|
||||
and you may offer support or warranty protection for a fee.
|
||||
|
||||
5. Conveying Modified Source Versions.
|
||||
|
||||
You may convey a work based on the Program, or the modifications to
|
||||
produce it from the Program, in the form of source code under the
|
||||
terms of section 4, provided that you also meet all of these conditions:
|
||||
|
||||
a) The work must carry prominent notices stating that you modified
|
||||
it, and giving a relevant date.
|
||||
|
||||
b) The work must carry prominent notices stating that it is
|
||||
released under this License and any conditions added under section
|
||||
7. This requirement modifies the requirement in section 4 to
|
||||
"keep intact all notices".
|
||||
|
||||
c) You must license the entire work, as a whole, under this
|
||||
License to anyone who comes into possession of a copy. This
|
||||
License will therefore apply, along with any applicable section 7
|
||||
additional terms, to the whole of the work, and all its parts,
|
||||
regardless of how they are packaged. This License gives no
|
||||
permission to license the work in any other way, but it does not
|
||||
invalidate such permission if you have separately received it.
|
||||
|
||||
d) If the work has interactive user interfaces, each must display
|
||||
Appropriate Legal Notices; however, if the Program has interactive
|
||||
interfaces that do not display Appropriate Legal Notices, your
|
||||
work need not make them do so.
|
||||
|
||||
A compilation of a covered work with other separate and independent
|
||||
works, which are not by their nature extensions of the covered work,
|
||||
and which are not combined with it such as to form a larger program,
|
||||
in or on a volume of a storage or distribution medium, is called an
|
||||
"aggregate" if the compilation and its resulting copyright are not
|
||||
used to limit the access or legal rights of the compilation's users
|
||||
beyond what the individual works permit. Inclusion of a covered work
|
||||
in an aggregate does not cause this License to apply to the other
|
||||
parts of the aggregate.
|
||||
|
||||
6. Conveying Non-Source Forms.
|
||||
|
||||
You may convey a covered work in object code form under the terms
|
||||
of sections 4 and 5, provided that you also convey the
|
||||
machine-readable Corresponding Source under the terms of this License,
|
||||
in one of these ways:
|
||||
|
||||
a) Convey the object code in, or embodied in, a physical product
|
||||
(including a physical distribution medium), accompanied by the
|
||||
Corresponding Source fixed on a durable physical medium
|
||||
customarily used for software interchange.
|
||||
|
||||
b) Convey the object code in, or embodied in, a physical product
|
||||
(including a physical distribution medium), accompanied by a
|
||||
written offer, valid for at least three years and valid for as
|
||||
long as you offer spare parts or customer support for that product
|
||||
model, to give anyone who possesses the object code either (1) a
|
||||
copy of the Corresponding Source for all the software in the
|
||||
product that is covered by this License, on a durable physical
|
||||
medium customarily used for software interchange, for a price no
|
||||
more than your reasonable cost of physically performing this
|
||||
conveying of source, or (2) access to copy the
|
||||
Corresponding Source from a network server at no charge.
|
||||
|
||||
c) Convey individual copies of the object code with a copy of the
|
||||
written offer to provide the Corresponding Source. This
|
||||
alternative is allowed only occasionally and noncommercially, and
|
||||
only if you received the object code with such an offer, in accord
|
||||
with subsection 6b.
|
||||
|
||||
d) Convey the object code by offering access from a designated
|
||||
place (gratis or for a charge), and offer equivalent access to the
|
||||
Corresponding Source in the same way through the same place at no
|
||||
further charge. You need not require recipients to copy the
|
||||
Corresponding Source along with the object code. If the place to
|
||||
copy the object code is a network server, the Corresponding Source
|
||||
may be on a different server (operated by you or a third party)
|
||||
that supports equivalent copying facilities, provided you maintain
|
||||
clear directions next to the object code saying where to find the
|
||||
Corresponding Source. Regardless of what server hosts the
|
||||
Corresponding Source, you remain obligated to ensure that it is
|
||||
available for as long as needed to satisfy these requirements.
|
||||
|
||||
e) Convey the object code using peer-to-peer transmission, provided
|
||||
you inform other peers where the object code and Corresponding
|
||||
Source of the work are being offered to the general public at no
|
||||
charge under subsection 6d.
|
||||
|
||||
A separable portion of the object code, whose source code is excluded
|
||||
from the Corresponding Source as a System Library, need not be
|
||||
included in conveying the object code work.
|
||||
|
||||
A "User Product" is either (1) a "consumer product", which means any
|
||||
tangible personal property which is normally used for personal, family,
|
||||
or household purposes, or (2) anything designed or sold for incorporation
|
||||
into a dwelling. In determining whether a product is a consumer product,
|
||||
doubtful cases shall be resolved in favor of coverage. For a particular
|
||||
product received by a particular user, "normally used" refers to a
|
||||
typical or common use of that class of product, regardless of the status
|
||||
of the particular user or of the way in which the particular user
|
||||
actually uses, or expects or is expected to use, the product. A product
|
||||
is a consumer product regardless of whether the product has substantial
|
||||
commercial, industrial or non-consumer uses, unless such uses represent
|
||||
the only significant mode of use of the product.
|
||||
|
||||
"Installation Information" for a User Product means any methods,
|
||||
procedures, authorization keys, or other information required to install
|
||||
and execute modified versions of a covered work in that User Product from
|
||||
a modified version of its Corresponding Source. The information must
|
||||
suffice to ensure that the continued functioning of the modified object
|
||||
code is in no case prevented or interfered with solely because
|
||||
modification has been made.
|
||||
|
||||
If you convey an object code work under this section in, or with, or
|
||||
specifically for use in, a User Product, and the conveying occurs as
|
||||
part of a transaction in which the right of possession and use of the
|
||||
User Product is transferred to the recipient in perpetuity or for a
|
||||
fixed term (regardless of how the transaction is characterized), the
|
||||
Corresponding Source conveyed under this section must be accompanied
|
||||
by the Installation Information. But this requirement does not apply
|
||||
if neither you nor any third party retains the ability to install
|
||||
modified object code on the User Product (for example, the work has
|
||||
been installed in ROM).
|
||||
|
||||
The requirement to provide Installation Information does not include a
|
||||
requirement to continue to provide support service, warranty, or updates
|
||||
for a work that has been modified or installed by the recipient, or for
|
||||
the User Product in which it has been modified or installed. Access to a
|
||||
network may be denied when the modification itself materially and
|
||||
adversely affects the operation of the network or violates the rules and
|
||||
protocols for communication across the network.
|
||||
|
||||
Corresponding Source conveyed, and Installation Information provided,
|
||||
in accord with this section must be in a format that is publicly
|
||||
documented (and with an implementation available to the public in
|
||||
source code form), and must require no special password or key for
|
||||
unpacking, reading or copying.
|
||||
|
||||
7. Additional Terms.
|
||||
|
||||
"Additional permissions" are terms that supplement the terms of this
|
||||
License by making exceptions from one or more of its conditions.
|
||||
Additional permissions that are applicable to the entire Program shall
|
||||
be treated as though they were included in this License, to the extent
|
||||
that they are valid under applicable law. If additional permissions
|
||||
apply only to part of the Program, that part may be used separately
|
||||
under those permissions, but the entire Program remains governed by
|
||||
this License without regard to the additional permissions.
|
||||
|
||||
When you convey a copy of a covered work, you may at your option
|
||||
remove any additional permissions from that copy, or from any part of
|
||||
it. (Additional permissions may be written to require their own
|
||||
removal in certain cases when you modify the work.) You may place
|
||||
additional permissions on material, added by you to a covered work,
|
||||
for which you have or can give appropriate copyright permission.
|
||||
|
||||
Notwithstanding any other provision of this License, for material you
|
||||
add to a covered work, you may (if authorized by the copyright holders of
|
||||
that material) supplement the terms of this License with terms:
|
||||
|
||||
a) Disclaiming warranty or limiting liability differently from the
|
||||
terms of sections 15 and 16 of this License; or
|
||||
|
||||
b) Requiring preservation of specified reasonable legal notices or
|
||||
author attributions in that material or in the Appropriate Legal
|
||||
Notices displayed by works containing it; or
|
||||
|
||||
c) Prohibiting misrepresentation of the origin of that material, or
|
||||
requiring that modified versions of such material be marked in
|
||||
reasonable ways as different from the original version; or
|
||||
|
||||
d) Limiting the use for publicity purposes of names of licensors or
|
||||
authors of the material; or
|
||||
|
||||
e) Declining to grant rights under trademark law for use of some
|
||||
trade names, trademarks, or service marks; or
|
||||
|
||||
f) Requiring indemnification of licensors and authors of that
|
||||
material by anyone who conveys the material (or modified versions of
|
||||
it) with contractual assumptions of liability to the recipient, for
|
||||
any liability that these contractual assumptions directly impose on
|
||||
those licensors and authors.
|
||||
|
||||
All other non-permissive additional terms are considered "further
|
||||
restrictions" within the meaning of section 10. If the Program as you
|
||||
received it, or any part of it, contains a notice stating that it is
|
||||
governed by this License along with a term that is a further
|
||||
restriction, you may remove that term. If a license document contains
|
||||
a further restriction but permits relicensing or conveying under this
|
||||
License, you may add to a covered work material governed by the terms
|
||||
of that license document, provided that the further restriction does
|
||||
not survive such relicensing or conveying.
|
||||
|
||||
If you add terms to a covered work in accord with this section, you
|
||||
must place, in the relevant source files, a statement of the
|
||||
additional terms that apply to those files, or a notice indicating
|
||||
where to find the applicable terms.
|
||||
|
||||
Additional terms, permissive or non-permissive, may be stated in the
|
||||
form of a separately written license, or stated as exceptions;
|
||||
the above requirements apply either way.
|
||||
|
||||
8. Termination.
|
||||
|
||||
You may not propagate or modify a covered work except as expressly
|
||||
provided under this License. Any attempt otherwise to propagate or
|
||||
modify it is void, and will automatically terminate your rights under
|
||||
this License (including any patent licenses granted under the third
|
||||
paragraph of section 11).
|
||||
|
||||
However, if you cease all violation of this License, then your
|
||||
license from a particular copyright holder is reinstated (a)
|
||||
provisionally, unless and until the copyright holder explicitly and
|
||||
finally terminates your license, and (b) permanently, if the copyright
|
||||
holder fails to notify you of the violation by some reasonable means
|
||||
prior to 60 days after the cessation.
|
||||
|
||||
Moreover, your license from a particular copyright holder is
|
||||
reinstated permanently if the copyright holder notifies you of the
|
||||
violation by some reasonable means, this is the first time you have
|
||||
received notice of violation of this License (for any work) from that
|
||||
copyright holder, and you cure the violation prior to 30 days after
|
||||
your receipt of the notice.
|
||||
|
||||
Termination of your rights under this section does not terminate the
|
||||
licenses of parties who have received copies or rights from you under
|
||||
this License. If your rights have been terminated and not permanently
|
||||
reinstated, you do not qualify to receive new licenses for the same
|
||||
material under section 10.
|
||||
|
||||
9. Acceptance Not Required for Having Copies.
|
||||
|
||||
You are not required to accept this License in order to receive or
|
||||
run a copy of the Program. Ancillary propagation of a covered work
|
||||
occurring solely as a consequence of using peer-to-peer transmission
|
||||
to receive a copy likewise does not require acceptance. However,
|
||||
nothing other than this License grants you permission to propagate or
|
||||
modify any covered work. These actions infringe copyright if you do
|
||||
not accept this License. Therefore, by modifying or propagating a
|
||||
covered work, you indicate your acceptance of this License to do so.
|
||||
|
||||
10. Automatic Licensing of Downstream Recipients.
|
||||
|
||||
Each time you convey a covered work, the recipient automatically
|
||||
receives a license from the original licensors, to run, modify and
|
||||
propagate that work, subject to this License. You are not responsible
|
||||
for enforcing compliance by third parties with this License.
|
||||
|
||||
An "entity transaction" is a transaction transferring control of an
|
||||
organization, or substantially all assets of one, or subdividing an
|
||||
organization, or merging organizations. If propagation of a covered
|
||||
work results from an entity transaction, each party to that
|
||||
transaction who receives a copy of the work also receives whatever
|
||||
licenses to the work the party's predecessor in interest had or could
|
||||
give under the previous paragraph, plus a right to possession of the
|
||||
Corresponding Source of the work from the predecessor in interest, if
|
||||
the predecessor has it or can get it with reasonable efforts.
|
||||
|
||||
You may not impose any further restrictions on the exercise of the
|
||||
rights granted or affirmed under this License. For example, you may
|
||||
not impose a license fee, royalty, or other charge for exercise of
|
||||
rights granted under this License, and you may not initiate litigation
|
||||
(including a cross-claim or counterclaim in a lawsuit) alleging that
|
||||
any patent claim is infringed by making, using, selling, offering for
|
||||
sale, or importing the Program or any portion of it.
|
||||
|
||||
11. Patents.
|
||||
|
||||
A "contributor" is a copyright holder who authorizes use under this
|
||||
License of the Program or a work on which the Program is based. The
|
||||
work thus licensed is called the contributor's "contributor version".
|
||||
|
||||
A contributor's "essential patent claims" are all patent claims
|
||||
owned or controlled by the contributor, whether already acquired or
|
||||
hereafter acquired, that would be infringed by some manner, permitted
|
||||
by this License, of making, using, or selling its contributor version,
|
||||
but do not include claims that would be infringed only as a
|
||||
consequence of further modification of the contributor version. For
|
||||
purposes of this definition, "control" includes the right to grant
|
||||
patent sublicenses in a manner consistent with the requirements of
|
||||
this License.
|
||||
|
||||
Each contributor grants you a non-exclusive, worldwide, royalty-free
|
||||
patent license under the contributor's essential patent claims, to
|
||||
make, use, sell, offer for sale, import and otherwise run, modify and
|
||||
propagate the contents of its contributor version.
|
||||
|
||||
In the following three paragraphs, a "patent license" is any express
|
||||
agreement or commitment, however denominated, not to enforce a patent
|
||||
(such as an express permission to practice a patent or covenant not to
|
||||
sue for patent infringement). To "grant" such a patent license to a
|
||||
party means to make such an agreement or commitment not to enforce a
|
||||
patent against the party.
|
||||
|
||||
If you convey a covered work, knowingly relying on a patent license,
|
||||
and the Corresponding Source of the work is not available for anyone
|
||||
to copy, free of charge and under the terms of this License, through a
|
||||
publicly available network server or other readily accessible means,
|
||||
then you must either (1) cause the Corresponding Source to be so
|
||||
available, or (2) arrange to deprive yourself of the benefit of the
|
||||
patent license for this particular work, or (3) arrange, in a manner
|
||||
consistent with the requirements of this License, to extend the patent
|
||||
license to downstream recipients. "Knowingly relying" means you have
|
||||
actual knowledge that, but for the patent license, your conveying the
|
||||
covered work in a country, or your recipient's use of the covered work
|
||||
in a country, would infringe one or more identifiable patents in that
|
||||
country that you have reason to believe are valid.
|
||||
|
||||
If, pursuant to or in connection with a single transaction or
|
||||
arrangement, you convey, or propagate by procuring conveyance of, a
|
||||
covered work, and grant a patent license to some of the parties
|
||||
receiving the covered work authorizing them to use, propagate, modify
|
||||
or convey a specific copy of the covered work, then the patent license
|
||||
you grant is automatically extended to all recipients of the covered
|
||||
work and works based on it.
|
||||
|
||||
A patent license is "discriminatory" if it does not include within
|
||||
the scope of its coverage, prohibits the exercise of, or is
|
||||
conditioned on the non-exercise of one or more of the rights that are
|
||||
specifically granted under this License. You may not convey a covered
|
||||
work if you are a party to an arrangement with a third party that is
|
||||
in the business of distributing software, under which you make payment
|
||||
to the third party based on the extent of your activity of conveying
|
||||
the work, and under which the third party grants, to any of the
|
||||
parties who would receive the covered work from you, a discriminatory
|
||||
patent license (a) in connection with copies of the covered work
|
||||
conveyed by you (or copies made from those copies), or (b) primarily
|
||||
for and in connection with specific products or compilations that
|
||||
contain the covered work, unless you entered into that arrangement,
|
||||
or that patent license was granted, prior to 28 March 2007.
|
||||
|
||||
Nothing in this License shall be construed as excluding or limiting
|
||||
any implied license or other defenses to infringement that may
|
||||
otherwise be available to you under applicable patent law.
|
||||
|
||||
12. No Surrender of Others' Freedom.
|
||||
|
||||
If conditions are imposed on you (whether by court order, agreement or
|
||||
otherwise) that contradict the conditions of this License, they do not
|
||||
excuse you from the conditions of this License. If you cannot convey a
|
||||
covered work so as to satisfy simultaneously your obligations under this
|
||||
License and any other pertinent obligations, then as a consequence you may
|
||||
not convey it at all. For example, if you agree to terms that obligate you
|
||||
to collect a royalty for further conveying from those to whom you convey
|
||||
the Program, the only way you could satisfy both those terms and this
|
||||
License would be to refrain entirely from conveying the Program.
|
||||
|
||||
13. Use with the GNU Affero General Public License.
|
||||
|
||||
Notwithstanding any other provision of this License, you have
|
||||
permission to link or combine any covered work with a work licensed
|
||||
under version 3 of the GNU Affero General Public License into a single
|
||||
combined work, and to convey the resulting work. The terms of this
|
||||
License will continue to apply to the part which is the covered work,
|
||||
but the special requirements of the GNU Affero General Public License,
|
||||
section 13, concerning interaction through a network will apply to the
|
||||
combination as such.
|
||||
|
||||
14. Revised Versions of this License.
|
||||
|
||||
The Free Software Foundation may publish revised and/or new versions of
|
||||
the GNU General Public License from time to time. Such new versions will
|
||||
be similar in spirit to the present version, but may differ in detail to
|
||||
address new problems or concerns.
|
||||
|
||||
Each version is given a distinguishing version number. If the
|
||||
Program specifies that a certain numbered version of the GNU General
|
||||
Public License "or any later version" applies to it, you have the
|
||||
option of following the terms and conditions either of that numbered
|
||||
version or of any later version published by the Free Software
|
||||
Foundation. If the Program does not specify a version number of the
|
||||
GNU General Public License, you may choose any version ever published
|
||||
by the Free Software Foundation.
|
||||
|
||||
If the Program specifies that a proxy can decide which future
|
||||
versions of the GNU General Public License can be used, that proxy's
|
||||
public statement of acceptance of a version permanently authorizes you
|
||||
to choose that version for the Program.
|
||||
|
||||
Later license versions may give you additional or different
|
||||
permissions. However, no additional obligations are imposed on any
|
||||
author or copyright holder as a result of your choosing to follow a
|
||||
later version.
|
||||
|
||||
15. Disclaimer of Warranty.
|
||||
|
||||
THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
|
||||
APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
|
||||
HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
|
||||
OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
|
||||
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
||||
PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
|
||||
IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
|
||||
ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
|
||||
|
||||
16. Limitation of Liability.
|
||||
|
||||
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
|
||||
WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
|
||||
THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
|
||||
GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
|
||||
USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
|
||||
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
|
||||
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
|
||||
EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
|
||||
SUCH DAMAGES.
|
||||
|
||||
17. Interpretation of Sections 15 and 16.
|
||||
|
||||
If the disclaimer of warranty and limitation of liability provided
|
||||
above cannot be given local legal effect according to their terms,
|
||||
reviewing courts shall apply local law that most closely approximates
|
||||
an absolute waiver of all civil liability in connection with the
|
||||
Program, unless a warranty or assumption of liability accompanies a
|
||||
copy of the Program in return for a fee.
|
||||
|
||||
END OF TERMS AND CONDITIONS
|
||||
|
||||
How to Apply These Terms to Your New Programs
|
||||
|
||||
If you develop a new program, and you want it to be of the greatest
|
||||
possible use to the public, the best way to achieve this is to make it
|
||||
free software which everyone can redistribute and change under these terms.
|
||||
|
||||
To do so, attach the following notices to the program. It is safest
|
||||
to attach them to the start of each source file to most effectively
|
||||
state the exclusion of warranty; and each file should have at least
|
||||
the "copyright" line and a pointer to where the full notice is found.
|
||||
|
||||
<one line to give the program's name and a brief idea of what it does.>
|
||||
Copyright (C) <year> <name of author>
|
||||
|
||||
This program is free software: you can redistribute it and/or modify
|
||||
it under the terms of the GNU General Public License as published by
|
||||
the Free Software Foundation, either version 3 of the License, or
|
||||
(at your option) any later version.
|
||||
|
||||
This program is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
GNU General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU General Public License
|
||||
along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
Also add information on how to contact you by electronic and paper mail.
|
||||
|
||||
If the program does terminal interaction, make it output a short
|
||||
notice like this when it starts in an interactive mode:
|
||||
|
||||
<program> Copyright (C) <year> <name of author>
|
||||
This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
|
||||
This is free software, and you are welcome to redistribute it
|
||||
under certain conditions; type `show c' for details.
|
||||
|
||||
The hypothetical commands `show w' and `show c' should show the appropriate
|
||||
parts of the General Public License. Of course, your program's commands
|
||||
might be different; for a GUI interface, you would use an "about box".
|
||||
|
||||
You should also get your employer (if you work as a programmer) or school,
|
||||
if any, to sign a "copyright disclaimer" for the program, if necessary.
|
||||
For more information on this, and how to apply and follow the GNU GPL, see
|
||||
<http://www.gnu.org/licenses/>.
|
||||
|
||||
The GNU General Public License does not permit incorporating your program
|
||||
into proprietary programs. If your program is a subroutine library, you
|
||||
may consider it more useful to permit linking proprietary applications with
|
||||
the library. If this is what you want to do, use the GNU Lesser General
|
||||
Public License instead of this License. But first, please read
|
||||
<http://www.gnu.org/philosophy/why-not-lgpl.html>.
|
17
Makefile.am
Normal file
17
Makefile.am
Normal file
|
@ -0,0 +1,17 @@
|
|||
include guile.am
|
||||
|
||||
SOURCES = \
|
||||
knots.scm \
|
||||
knots/non-blocking.scm \
|
||||
knots/parallelism.scm \
|
||||
knots/promise.scm \
|
||||
knots/queue.scm \
|
||||
knots/resource-pool.scm \
|
||||
knots/timeout.scm \
|
||||
knots/web-server.scm \
|
||||
knots/worker-threads.scm
|
||||
|
||||
EXTRA_DIST = \
|
||||
README \
|
||||
bootstrap \
|
||||
pre-inst-env.in
|
4
README
Normal file
4
README
Normal file
|
@ -0,0 +1,4 @@
|
|||
-*- mode: org -*-
|
||||
|
||||
This Guile library provides useful patterns and functionality to use
|
||||
Guile Fibers.
|
3
bootstrap
Executable file
3
bootstrap
Executable file
|
@ -0,0 +1,3 @@
|
|||
#! /bin/sh
|
||||
|
||||
autoreconf --verbose --install --force
|
19
configure.ac
Normal file
19
configure.ac
Normal file
|
@ -0,0 +1,19 @@
|
|||
AC_INIT([guile-knots], [0.1])
|
||||
AC_CONFIG_AUX_DIR([build-aux])
|
||||
AM_INIT_AUTOMAKE([-Wall -Werror foreign])
|
||||
|
||||
GUILE_PKG([3.0])
|
||||
GUILE_PROGS
|
||||
if test "x$GUILD" = "x"; then
|
||||
AC_MSG_ERROR(['guild' binary not found; please check your guile 3 installation.])
|
||||
fi
|
||||
|
||||
if test "$cross_compiling" != no; then
|
||||
GUILE_TARGET="--target=$host_alias"
|
||||
AC_SUBST([GUILE_TARGET])
|
||||
fi
|
||||
|
||||
AC_CONFIG_FILES([Makefile])
|
||||
AC_CONFIG_FILES([pre-inst-env], [chmod +x pre-inst-env])
|
||||
|
||||
AC_OUTPUT
|
21
guile.am
Normal file
21
guile.am
Normal file
|
@ -0,0 +1,21 @@
|
|||
moddir=$(datadir)/guile/site/$(GUILE_EFFECTIVE_VERSION)
|
||||
godir=$(libdir)/guile/$(GUILE_EFFECTIVE_VERSION)/site-ccache
|
||||
|
||||
GOBJECTS = $(SOURCES:%.scm=%.go)
|
||||
|
||||
nobase_dist_mod_DATA = $(SOURCES) $(NOCOMP_SOURCES)
|
||||
nobase_go_DATA = $(GOBJECTS)
|
||||
|
||||
# Make sure source files are installed first, so that the mtime of
|
||||
# installed compiled files is greater than that of installed source
|
||||
# files. See
|
||||
# <http://lists.gnu.org/archive/html/guile-devel/2010-07/msg00125.html>
|
||||
# for details.
|
||||
guile_install_go_files = install-nobase_goDATA
|
||||
$(guile_install_go_files): install-nobase_dist_modDATA
|
||||
|
||||
CLEANFILES = $(GOBJECTS)
|
||||
GUILE_WARNINGS = -Wunbound-variable -Warity-mismatch -Wformat
|
||||
SUFFIXES = .scm .go
|
||||
.scm.go:
|
||||
$(AM_V_GEN)$(top_builddir)/pre-inst-env $(GUILD) compile $(GUILE_TARGET) $(GUILE_WARNINGS) -o "$@" "$<"
|
50
guix-dev.scm
Normal file
50
guix-dev.scm
Normal file
|
@ -0,0 +1,50 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
;;; Run the following command to enter a development environment for
|
||||
;;; Guile Knots:
|
||||
;;;
|
||||
;;; $ guix environment -l guix-dev.scm
|
||||
|
||||
(use-modules ((guix licenses) #:prefix license:)
|
||||
(guix packages)
|
||||
(guix build-system gnu)
|
||||
(gnu packages)
|
||||
(gnu packages autotools)
|
||||
(gnu packages guile)
|
||||
(gnu packages guile-xyz)
|
||||
(gnu packages pkg-config)
|
||||
(srfi srfi-1))
|
||||
|
||||
(package
|
||||
(name "guile-knots")
|
||||
(version "0.0.0")
|
||||
(source #f)
|
||||
(build-system gnu-build-system)
|
||||
(inputs
|
||||
(list guile-3.0
|
||||
guile-fibers))
|
||||
(native-inputs
|
||||
(list autoconf
|
||||
automake
|
||||
pkg-config))
|
||||
(synopsis "TODO")
|
||||
(description "TODO")
|
||||
(home-page "TODO")
|
||||
(license license:gpl3+))
|
21
knots.scm
Normal file
21
knots.scm
Normal file
|
@ -0,0 +1,21 @@
|
|||
(define-module (knots)
|
||||
#:use-module (ice-9 suspendable-ports)
|
||||
#:export (call-with-default-io-waiters
|
||||
|
||||
wait-when-system-clock-behind))
|
||||
|
||||
(define (call-with-default-io-waiters thunk)
|
||||
(parameterize
|
||||
((current-read-waiter (@@ (ice-9 suspendable-ports)
|
||||
default-read-waiter))
|
||||
(current-write-waiter (@@ (ice-9 suspendable-ports)
|
||||
default-write-waiter)))
|
||||
(thunk)))
|
||||
|
||||
(define (wait-when-system-clock-behind)
|
||||
(let ((start-of-the-year-2000 946684800))
|
||||
(while (< (current-time)
|
||||
start-of-the-year-2000)
|
||||
(simple-format (current-error-port)
|
||||
"warning: system clock potentially behind, waiting\n")
|
||||
(sleep 20))))
|
63
knots/non-blocking.scm
Normal file
63
knots/non-blocking.scm
Normal file
|
@ -0,0 +1,63 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots non-blocking)
|
||||
#:use-module (web uri)
|
||||
#:use-module (web client)
|
||||
#:export (non-blocking-port
|
||||
nonblocking-open-socket-for-uri))
|
||||
|
||||
(define (non-blocking-port port)
|
||||
"Make PORT non-blocking and return it."
|
||||
(let ((flags (fcntl port F_GETFL)))
|
||||
(when (zero? (logand O_NONBLOCK flags))
|
||||
(fcntl port F_SETFL (logior O_NONBLOCK flags)))
|
||||
port))
|
||||
|
||||
(define* (nonblocking-open-socket-for-uri uri
|
||||
#:key (verify-certificate? #t))
|
||||
(define tls-wrap
|
||||
(@@ (web client) tls-wrap))
|
||||
|
||||
(define https?
|
||||
(eq? 'https (uri-scheme uri)))
|
||||
|
||||
(define plain-uri
|
||||
(if https?
|
||||
(build-uri
|
||||
'http
|
||||
#:userinfo (uri-userinfo uri)
|
||||
#:host (uri-host uri)
|
||||
#:port (or (uri-port uri) 443)
|
||||
#:path (uri-path uri)
|
||||
#:query (uri-query uri)
|
||||
#:fragment (uri-fragment uri))
|
||||
uri))
|
||||
|
||||
(let ((s (open-socket-for-uri plain-uri)))
|
||||
(if https?
|
||||
(let ((port
|
||||
(tls-wrap s (uri-host uri)
|
||||
#:verify-certificate? verify-certificate?)))
|
||||
;; Guile/guile-gnutls don't handle the handshake happening on a non
|
||||
;; blocking socket, so change the behavior here.
|
||||
(non-blocking-port s)
|
||||
port)
|
||||
(non-blocking-port s))))
|
||||
|
197
knots/parallelism.scm
Normal file
197
knots/parallelism.scm
Normal file
|
@ -0,0 +1,197 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots parallelism)
|
||||
#:use-module (srfi srfi-1)
|
||||
#:use-module (srfi srfi-71)
|
||||
#:use-module (ice-9 match)
|
||||
#:use-module (fibers)
|
||||
#:use-module (fibers channels)
|
||||
#:use-module (fibers operations)
|
||||
#:export (fibers-batch-map
|
||||
fibers-map
|
||||
|
||||
fibers-map-with-progress
|
||||
|
||||
fibers-batch-for-each
|
||||
fibers-for-each
|
||||
|
||||
fibers-parallel
|
||||
fibers-let))
|
||||
|
||||
;; Like split-at, but don't care about the order of the resulting lists, and
|
||||
;; don't error if the list is shorter than i elements
|
||||
(define (split-at* lst i)
|
||||
(let lp ((l lst) (n i) (acc '()))
|
||||
(if (or (<= n 0) (null? l))
|
||||
(values (reverse! acc) l)
|
||||
(lp (cdr l) (- n 1) (cons (car l) acc)))))
|
||||
|
||||
;; As this can be called with lists with tens of thousands of items in them,
|
||||
;; batch the
|
||||
(define (get-batch batch-size lists)
|
||||
(let ((split-lists
|
||||
(map (lambda (lst)
|
||||
(let ((batch rest (split-at* lst batch-size)))
|
||||
(cons batch rest)))
|
||||
lists)))
|
||||
(values (map car split-lists)
|
||||
(map cdr split-lists))))
|
||||
|
||||
(define (defer-to-parallel-fiber thunk)
|
||||
(let ((reply (make-channel)))
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(put-message reply (cons 'exception exn)))
|
||||
(lambda ()
|
||||
(call-with-values
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
thunk
|
||||
(lambda _
|
||||
(backtrace))))
|
||||
(lambda vals
|
||||
(put-message reply vals))))
|
||||
#:unwind? #t))
|
||||
#:parallel? #t)
|
||||
reply))
|
||||
|
||||
(define (fetch-result-of-defered-thunks . reply-channels)
|
||||
(let ((responses (map get-message
|
||||
reply-channels)))
|
||||
(map
|
||||
(match-lambda
|
||||
(('exception . exn)
|
||||
(raise-exception exn))
|
||||
(result
|
||||
(apply values result)))
|
||||
responses)))
|
||||
|
||||
(define (fibers-batch-map proc batch-size . lists)
|
||||
(let loop ((lists lists)
|
||||
(result '()))
|
||||
(let ((batch
|
||||
rest
|
||||
(get-batch batch-size lists)))
|
||||
(if (any null? batch)
|
||||
result
|
||||
(let ((response-channels
|
||||
(apply map
|
||||
(lambda args
|
||||
(defer-to-parallel-fiber
|
||||
(lambda ()
|
||||
(apply proc args))))
|
||||
batch)))
|
||||
(loop rest
|
||||
(append! result
|
||||
(apply fetch-result-of-defered-thunks
|
||||
response-channels))))))))
|
||||
|
||||
(define (fibers-map proc . lists)
|
||||
(apply fibers-batch-map proc 20 lists))
|
||||
|
||||
(define (fibers-batch-for-each proc batch-size . lists)
|
||||
(let loop ((lists lists))
|
||||
(let ((batch
|
||||
rest
|
||||
(get-batch batch-size lists)))
|
||||
(if (any null? batch)
|
||||
*unspecified*
|
||||
(let ((response-channels
|
||||
(apply map
|
||||
(lambda args
|
||||
(defer-to-parallel-fiber
|
||||
(lambda ()
|
||||
(apply proc args))))
|
||||
batch)))
|
||||
(apply fetch-result-of-defered-thunks
|
||||
response-channels)
|
||||
(loop rest))))))
|
||||
|
||||
(define (fibers-for-each proc . lists)
|
||||
(apply fibers-batch-for-each proc 20 lists))
|
||||
|
||||
(define-syntax fibers-parallel
|
||||
(lambda (x)
|
||||
(syntax-case x ()
|
||||
((_ e0 ...)
|
||||
(with-syntax (((tmp0 ...) (generate-temporaries (syntax (e0 ...)))))
|
||||
#'(let ((tmp0 (defer-to-parallel-fiber
|
||||
(lambda ()
|
||||
e0)))
|
||||
...)
|
||||
(apply values (fetch-result-of-defered-thunks tmp0 ...))))))))
|
||||
|
||||
(define-syntax-rule (fibers-let ((v e) ...) b0 b1 ...)
|
||||
(call-with-values
|
||||
(lambda () (fibers-parallel e ...))
|
||||
(lambda (v ...)
|
||||
b0 b1 ...)))
|
||||
|
||||
(define* (fibers-map-with-progress proc lists #:key report)
|
||||
(let loop ((channels-to-results
|
||||
(apply map
|
||||
(lambda args
|
||||
(cons (defer-to-parallel-fiber
|
||||
(lambda ()
|
||||
(apply proc args)))
|
||||
#f))
|
||||
lists)))
|
||||
(let ((active-channels
|
||||
(filter-map car channels-to-results)))
|
||||
(when report
|
||||
(report (apply map
|
||||
list
|
||||
(map cdr channels-to-results)
|
||||
lists)))
|
||||
(if (null? active-channels)
|
||||
(map
|
||||
(match-lambda
|
||||
((#f . ('exception . exn))
|
||||
(raise-exception exn))
|
||||
((#f . ('result . val))
|
||||
val))
|
||||
channels-to-results)
|
||||
(loop
|
||||
(perform-operation
|
||||
(apply
|
||||
choice-operation
|
||||
(filter-map
|
||||
(lambda (p)
|
||||
(match p
|
||||
((channel . _)
|
||||
(if channel
|
||||
(wrap-operation
|
||||
(get-operation channel)
|
||||
(lambda (result)
|
||||
(map (match-lambda
|
||||
((c . r)
|
||||
(if (eq? channel c)
|
||||
(cons #f
|
||||
(match result
|
||||
(('exception . exn)
|
||||
result)
|
||||
(_
|
||||
(cons 'result result))))
|
||||
(cons c r))))
|
||||
channels-to-results)))
|
||||
#f))))
|
||||
channels-to-results))))))))
|
78
knots/promise.scm
Normal file
78
knots/promise.scm
Normal file
|
@ -0,0 +1,78 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots promise)
|
||||
#:use-module (srfi srfi-9)
|
||||
#:use-module (ice-9 atomic)
|
||||
#:use-module (fibers)
|
||||
#:use-module (fibers conditions)
|
||||
#:export (fibers-delay
|
||||
fibers-force
|
||||
fibers-promise-reset))
|
||||
|
||||
(define-record-type <fibers-promise>
|
||||
(make-fibers-promise thunk values-box evaluated-condition)
|
||||
fibers-promise?
|
||||
(thunk fibers-promise-thunk)
|
||||
(values-box fibers-promise-values-box)
|
||||
(evaluated-condition fibers-promise-evaluated-condition))
|
||||
|
||||
(define (fibers-delay thunk)
|
||||
(make-fibers-promise
|
||||
thunk
|
||||
(make-atomic-box #f)
|
||||
(make-condition)))
|
||||
|
||||
(define (fibers-force fp)
|
||||
(let ((res (atomic-box-compare-and-swap!
|
||||
(fibers-promise-values-box fp)
|
||||
#f
|
||||
'started)))
|
||||
(if (eq? #f res)
|
||||
(call-with-values
|
||||
(lambda ()
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(atomic-box-set! (fibers-promise-values-box fp)
|
||||
exn)
|
||||
(signal-condition!
|
||||
(fibers-promise-evaluated-condition fp))
|
||||
(raise-exception exn))
|
||||
(fibers-promise-thunk fp)
|
||||
#:unwind? #t))
|
||||
(lambda vals
|
||||
(atomic-box-set! (fibers-promise-values-box fp)
|
||||
vals)
|
||||
(signal-condition!
|
||||
(fibers-promise-evaluated-condition fp))
|
||||
(apply values vals)))
|
||||
(if (eq? res 'started)
|
||||
(begin
|
||||
(wait (fibers-promise-evaluated-condition fp))
|
||||
(let ((result (atomic-box-ref (fibers-promise-values-box fp))))
|
||||
(if (exception? result)
|
||||
(raise-exception result)
|
||||
(apply values result))))
|
||||
(if (exception? res)
|
||||
(raise-exception res)
|
||||
(apply values res))))))
|
||||
|
||||
(define (fibers-promise-reset fp)
|
||||
(atomic-box-set! (fibers-promise-values-box fp)
|
||||
#f))
|
47
knots/queue.scm
Normal file
47
knots/queue.scm
Normal file
|
@ -0,0 +1,47 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots queue)
|
||||
#:use-module (ice-9 q)
|
||||
#:use-module (fibers)
|
||||
#:use-module (fibers channels)
|
||||
#:use-module (fibers operations)
|
||||
#:export (spawn-queueing-fiber))
|
||||
|
||||
(define (spawn-queueing-fiber dest-channel)
|
||||
(define queue (make-q))
|
||||
|
||||
(let ((queue-channel (make-channel)))
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(while #t
|
||||
(if (q-empty? queue)
|
||||
(enq! queue
|
||||
(perform-operation
|
||||
(get-operation queue-channel)))
|
||||
(let ((front (q-front queue)))
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wrap-operation (get-operation queue-channel)
|
||||
(lambda (val)
|
||||
(enq! queue val)))
|
||||
(wrap-operation (put-operation dest-channel front)
|
||||
(lambda _
|
||||
(q-pop! queue))))))))))
|
||||
queue-channel))
|
485
knots/resource-pool.scm
Normal file
485
knots/resource-pool.scm
Normal file
|
@ -0,0 +1,485 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots resource-pool)
|
||||
#:use-module (srfi srfi-1)
|
||||
#:use-module (srfi srfi-9)
|
||||
#:use-module (ice-9 match)
|
||||
#:use-module (ice-9 exceptions)
|
||||
#:use-module (fibers)
|
||||
#:use-module (fibers timers)
|
||||
#:use-module (fibers channels)
|
||||
#:use-module (fibers scheduler)
|
||||
#:use-module (fibers operations)
|
||||
#:export (resource-pool?
|
||||
|
||||
make-resource-pool
|
||||
destroy-resource-pool
|
||||
|
||||
resource-pool-default-timeout
|
||||
resource-pool-retry-checkout-timeout
|
||||
|
||||
&resource-pool-timeout
|
||||
resource-pool-timeout-error?
|
||||
|
||||
resource-pool-default-timeout-handler
|
||||
|
||||
call-with-resource-from-pool
|
||||
with-resource-from-pool
|
||||
|
||||
resource-pool-stats))
|
||||
|
||||
(define-record-type <resource-pool>
|
||||
(make-resource-pool-record name channel)
|
||||
resource-pool?
|
||||
(name resource-pool-name)
|
||||
(channel resource-pool-channel))
|
||||
|
||||
(define* (make-resource-pool initializer max-size
|
||||
#:key (min-size max-size)
|
||||
(idle-seconds #f)
|
||||
(delay-logger (const #f))
|
||||
(duration-logger (const #f))
|
||||
destructor
|
||||
lifetime
|
||||
scheduler
|
||||
(name "unnamed")
|
||||
;; Add options for customizing timeouts
|
||||
)
|
||||
(define (initializer/safe)
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"exception running ~A resource pool initializer: ~A:\n ~A\n"
|
||||
name
|
||||
initializer
|
||||
exn)
|
||||
#f)
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
initializer
|
||||
(lambda args
|
||||
(backtrace))))
|
||||
#:unwind? #t))
|
||||
|
||||
(define (destructor/safe args)
|
||||
(let ((success?
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"exception running resource pool destructor (~A): ~A:\n ~A\n"
|
||||
name
|
||||
destructor
|
||||
exn)
|
||||
#f)
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
(lambda ()
|
||||
(destructor args)
|
||||
#t)
|
||||
(lambda _
|
||||
(backtrace))))
|
||||
#:unwind? #t)))
|
||||
|
||||
(or success?
|
||||
#t
|
||||
(begin
|
||||
(sleep 5)
|
||||
(destructor/safe args)))))
|
||||
|
||||
(let ((channel (make-channel))
|
||||
(checkout-failure-count 0))
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(when idle-seconds
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(while #t
|
||||
(sleep idle-seconds)
|
||||
(put-message channel '(check-for-idle-resources))))))
|
||||
|
||||
(while #t
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"exception in the ~A pool fiber: ~A\n"
|
||||
name
|
||||
exn))
|
||||
(lambda ()
|
||||
(let loop ((resources '())
|
||||
(available '())
|
||||
(waiters '())
|
||||
(resources-last-used '()))
|
||||
|
||||
(match (get-message channel)
|
||||
(('checkout reply)
|
||||
(if (null? available)
|
||||
(if (= (length resources) max-size)
|
||||
(loop resources
|
||||
available
|
||||
(cons reply waiters)
|
||||
resources-last-used)
|
||||
(let ((new-resource (initializer/safe)))
|
||||
(if new-resource
|
||||
(let ((checkout-success?
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wrap-operation
|
||||
(put-operation reply new-resource)
|
||||
(const #t))
|
||||
(wrap-operation (sleep-operation 1)
|
||||
(const #f))))))
|
||||
(unless checkout-success?
|
||||
(set! checkout-failure-count
|
||||
(+ 1 checkout-failure-count)))
|
||||
|
||||
(loop (cons new-resource resources)
|
||||
(if checkout-success?
|
||||
available
|
||||
(cons new-resource available))
|
||||
waiters
|
||||
(cons (get-internal-real-time)
|
||||
resources-last-used)))
|
||||
(loop resources
|
||||
available
|
||||
(cons reply waiters)
|
||||
resources-last-used))))
|
||||
(let ((checkout-success?
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wrap-operation
|
||||
(put-operation reply (car available))
|
||||
(const #t))
|
||||
(wrap-operation (sleep-operation 1)
|
||||
(const #f))))))
|
||||
(unless checkout-success?
|
||||
(set! checkout-failure-count
|
||||
(+ 1 checkout-failure-count)))
|
||||
|
||||
(if checkout-success?
|
||||
(loop resources
|
||||
(cdr available)
|
||||
waiters
|
||||
resources-last-used)
|
||||
(loop resources
|
||||
available
|
||||
waiters
|
||||
resources-last-used)))))
|
||||
(('return resource)
|
||||
(if (null? waiters)
|
||||
(loop resources
|
||||
(cons resource available)
|
||||
waiters
|
||||
(begin
|
||||
(list-set!
|
||||
resources-last-used
|
||||
(list-index (lambda (x)
|
||||
(eq? x resource))
|
||||
resources)
|
||||
(get-internal-real-time))
|
||||
resources-last-used))
|
||||
(let ((checkout-success?
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wrap-operation
|
||||
(put-operation (last waiters)
|
||||
resource)
|
||||
(const #t))
|
||||
(wrap-operation (sleep-operation 1)
|
||||
(const #f))))))
|
||||
(unless checkout-success?
|
||||
(set! checkout-failure-count
|
||||
(+ 1 checkout-failure-count)))
|
||||
|
||||
(if checkout-success?
|
||||
(loop resources
|
||||
available
|
||||
(drop-right! waiters 1)
|
||||
(begin
|
||||
(list-set!
|
||||
resources-last-used
|
||||
(list-index (lambda (x)
|
||||
(eq? x resource))
|
||||
resources)
|
||||
(get-internal-real-time))
|
||||
resources-last-used))
|
||||
(begin
|
||||
(for-each
|
||||
(lambda (waiter)
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(put-operation waiter 'resource-pool-retry-checkout)
|
||||
(sleep-operation 10))))))
|
||||
waiters)
|
||||
|
||||
(loop resources
|
||||
(cons resource available)
|
||||
'()
|
||||
(begin
|
||||
(list-set!
|
||||
resources-last-used
|
||||
(list-index (lambda (x)
|
||||
(eq? x resource))
|
||||
resources)
|
||||
(get-internal-real-time))
|
||||
resources-last-used)))))))
|
||||
(('stats reply)
|
||||
(let ((stats
|
||||
`((resources . ,(length resources))
|
||||
(available . ,(length available))
|
||||
(waiters . ,(length waiters))
|
||||
(checkout-failure-count . ,checkout-failure-count))))
|
||||
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wrap-operation
|
||||
(put-operation reply stats)
|
||||
(const #t))
|
||||
(wrap-operation (sleep-operation 1)
|
||||
(const #f)))))))
|
||||
|
||||
(loop resources
|
||||
available
|
||||
waiters
|
||||
resources-last-used))
|
||||
(('check-for-idle-resources)
|
||||
(let* ((resources-last-used-seconds
|
||||
(map
|
||||
(lambda (internal-time)
|
||||
(/ (- (get-internal-real-time) internal-time)
|
||||
internal-time-units-per-second))
|
||||
resources-last-used))
|
||||
(resources-to-destroy
|
||||
(filter-map
|
||||
(lambda (resource last-used-seconds)
|
||||
(if (and (member resource available)
|
||||
(> last-used-seconds idle-seconds))
|
||||
resource
|
||||
#f))
|
||||
resources
|
||||
resources-last-used-seconds)))
|
||||
|
||||
(for-each
|
||||
(lambda (resource)
|
||||
(destructor/safe resource))
|
||||
resources-to-destroy)
|
||||
|
||||
(loop (lset-difference eq? resources resources-to-destroy)
|
||||
(lset-difference eq? available resources-to-destroy)
|
||||
waiters
|
||||
(filter-map
|
||||
(lambda (resource last-used)
|
||||
(if (memq resource resources-to-destroy)
|
||||
#f
|
||||
last-used))
|
||||
resources
|
||||
resources-last-used))))
|
||||
(('destroy reply)
|
||||
(if (= (length resources) (length available))
|
||||
(begin
|
||||
(for-each
|
||||
(lambda (resource)
|
||||
(destructor/safe resource))
|
||||
resources)
|
||||
(put-message reply 'destroy-success))
|
||||
(begin
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(put-operation reply 'resource-pool-destroy-failed)
|
||||
(sleep-operation 10)))))
|
||||
(loop resources
|
||||
available
|
||||
waiters
|
||||
resources-last-used))))
|
||||
(unknown
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"unrecognised message to ~A resource pool channel: ~A\n"
|
||||
name
|
||||
unknown)
|
||||
(loop resources
|
||||
available
|
||||
waiters
|
||||
resources-last-used)))))
|
||||
#:unwind? #t)))
|
||||
(or scheduler
|
||||
(current-scheduler)))
|
||||
|
||||
(make-resource-pool-record name channel)))
|
||||
|
||||
(define (destroy-resource-pool pool)
|
||||
(let ((reply (make-channel)))
|
||||
(put-message (resource-pool-channel pool)
|
||||
(list 'destroy reply))
|
||||
(let ((msg (get-message reply)))
|
||||
(unless (eq? msg 'destroy-success)
|
||||
(error msg)))))
|
||||
|
||||
(define resource-pool-default-timeout
|
||||
(make-parameter #f))
|
||||
|
||||
(define resource-pool-retry-checkout-timeout
|
||||
(make-parameter 5))
|
||||
|
||||
(define &resource-pool-timeout
|
||||
(make-exception-type '&recource-pool-timeout
|
||||
&error
|
||||
'(name)))
|
||||
|
||||
(define make-resource-pool-timeout-error
|
||||
(record-constructor &resource-pool-timeout))
|
||||
|
||||
(define resource-pool-timeout-error?
|
||||
(record-predicate &resource-pool-timeout))
|
||||
|
||||
(define resource-pool-default-timeout-handler
|
||||
(make-parameter #f))
|
||||
|
||||
(define* (call-with-resource-from-pool
|
||||
pool proc #:key (timeout 'default)
|
||||
(timeout-handler (resource-pool-default-timeout-handler)))
|
||||
"Call PROC with a resource from POOL, blocking until a resource becomes
|
||||
available. Return the resource once PROC has returned."
|
||||
|
||||
(define retry-timeout
|
||||
(resource-pool-retry-checkout-timeout))
|
||||
|
||||
(define timeout-or-default
|
||||
(if (eq? timeout 'default)
|
||||
(resource-pool-default-timeout)
|
||||
timeout))
|
||||
|
||||
(let ((resource
|
||||
(let ((reply (make-channel)))
|
||||
(let loop ((start-time (get-internal-real-time)))
|
||||
(let ((request-success?
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wrap-operation
|
||||
(put-operation (resource-pool-channel pool)
|
||||
`(checkout ,reply))
|
||||
(const #t))
|
||||
(wrap-operation (sleep-operation (or timeout-or-default
|
||||
retry-timeout))
|
||||
(const #f))))))
|
||||
(if request-success?
|
||||
(let ((time-remaining
|
||||
(- (or timeout-or-default
|
||||
retry-timeout)
|
||||
(/ (- (get-internal-real-time)
|
||||
start-time)
|
||||
internal-time-units-per-second))))
|
||||
(if (> time-remaining 0)
|
||||
(let ((response
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(get-operation reply)
|
||||
(wrap-operation (sleep-operation time-remaining)
|
||||
(const #f))))))
|
||||
(if (or (not response)
|
||||
(eq? response 'resource-pool-retry-checkout))
|
||||
(if (> (- (or timeout-or-default
|
||||
retry-timeout)
|
||||
(/ (- (get-internal-real-time)
|
||||
start-time)
|
||||
internal-time-units-per-second))
|
||||
0)
|
||||
(loop start-time)
|
||||
(if (eq? timeout-or-default #f)
|
||||
(loop (get-internal-real-time))
|
||||
#f))
|
||||
response))
|
||||
(if (eq? timeout-or-default #f)
|
||||
(loop (get-internal-real-time))
|
||||
#f)))
|
||||
(if (eq? timeout-or-default #f)
|
||||
(loop (get-internal-real-time))
|
||||
#f)))))))
|
||||
|
||||
(when (or (not resource)
|
||||
(eq? resource 'resource-pool-retry-checkout))
|
||||
(when timeout-handler
|
||||
(timeout-handler pool proc timeout))
|
||||
|
||||
(raise-exception
|
||||
(make-resource-pool-timeout-error (resource-pool-name pool))))
|
||||
|
||||
(with-exception-handler
|
||||
(lambda (exception)
|
||||
(put-message (resource-pool-channel pool)
|
||||
`(return ,resource))
|
||||
(raise-exception exception))
|
||||
(lambda ()
|
||||
(call-with-values
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
(lambda ()
|
||||
(proc resource))
|
||||
(lambda _
|
||||
(backtrace))))
|
||||
(lambda vals
|
||||
(put-message (resource-pool-channel pool)
|
||||
`(return ,resource))
|
||||
(apply values vals))))
|
||||
#:unwind? #t)))
|
||||
|
||||
(define-syntax-rule (with-resource-from-pool pool resource exp ...)
|
||||
(call-with-resource-from-pool
|
||||
pool
|
||||
(lambda (resource) exp ...)))
|
||||
|
||||
(define* (resource-pool-stats pool #:key (timeout 5))
|
||||
(let ((reply (make-channel))
|
||||
(start-time (get-internal-real-time)))
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wrap-operation
|
||||
(put-operation (resource-pool-channel pool)
|
||||
`(stats ,reply))
|
||||
(const #t))
|
||||
(wrap-operation (sleep-operation timeout)
|
||||
(lambda _
|
||||
(raise-exception
|
||||
(make-resource-pool-timeout-error))))))
|
||||
|
||||
(let ((time-remaining
|
||||
(- timeout
|
||||
(/ (- (get-internal-real-time)
|
||||
start-time)
|
||||
internal-time-units-per-second))))
|
||||
(if (> time-remaining 0)
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(get-operation reply)
|
||||
(wrap-operation (sleep-operation time-remaining)
|
||||
(lambda _
|
||||
(raise-exception
|
||||
(make-resource-pool-timeout-error))))))
|
||||
(raise-exception
|
||||
(make-resource-pool-timeout-error))))))
|
||||
|
200
knots/timeout.scm
Normal file
200
knots/timeout.scm
Normal file
|
@ -0,0 +1,200 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots timeout)
|
||||
#:use-module (srfi srfi-71)
|
||||
#:use-module (ice-9 match)
|
||||
#:use-module (ice-9 atomic)
|
||||
#:use-module (ice-9 exceptions)
|
||||
#:use-module (ice-9 ports internal)
|
||||
#:use-module (ice-9 suspendable-ports)
|
||||
#:use-module (fibers)
|
||||
#:use-module (fibers timers)
|
||||
#:use-module (fibers channels)
|
||||
#:use-module (fibers scheduler)
|
||||
#:use-module (fibers operations)
|
||||
#:export (with-fibers-timeout
|
||||
|
||||
&port-timeout
|
||||
port-timeout-error?
|
||||
|
||||
&port-read-timeout
|
||||
port-read-timeout-error
|
||||
|
||||
&port-write-timeout
|
||||
port-write-timeout-error?
|
||||
|
||||
with-port-timeouts))
|
||||
|
||||
(define* (with-fibers-timeout thunk #:key timeout on-timeout)
|
||||
(let ((channel (make-channel)))
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(put-operation channel (cons 'exception exn))
|
||||
(sleep-operation timeout))))
|
||||
(lambda ()
|
||||
(call-with-values thunk
|
||||
(lambda vals
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(put-operation channel vals)
|
||||
(sleep-operation timeout))))))
|
||||
#:unwind? #t)))
|
||||
|
||||
(match (perform-operation
|
||||
(choice-operation
|
||||
(get-operation channel)
|
||||
(wrap-operation (sleep-operation timeout)
|
||||
(const 'timeout))))
|
||||
('timeout
|
||||
(on-timeout))
|
||||
(('exception . exn)
|
||||
(raise-exception exn))
|
||||
(vals
|
||||
(apply values vals)))))
|
||||
|
||||
(define &port-timeout
|
||||
(make-exception-type '&port-timeout
|
||||
&external-error
|
||||
'(thunk port)))
|
||||
|
||||
(define make-port-timeout-error
|
||||
(record-constructor &port-timeout))
|
||||
|
||||
(define port-timeout-error?
|
||||
(record-predicate &port-timeout))
|
||||
|
||||
(define &port-read-timeout
|
||||
(make-exception-type '&port-read-timeout
|
||||
&port-timeout
|
||||
'()))
|
||||
|
||||
(define make-port-read-timeout-error
|
||||
(record-constructor &port-read-timeout))
|
||||
|
||||
(define port-read-timeout-error?
|
||||
(record-predicate &port-read-timeout))
|
||||
|
||||
(define &port-write-timeout
|
||||
(make-exception-type '&port-write-timeout
|
||||
&port-timeout
|
||||
'()))
|
||||
|
||||
(define make-port-write-timeout-error
|
||||
(record-constructor &port-write-timeout))
|
||||
|
||||
(define port-write-timeout-error?
|
||||
(record-predicate &port-write-timeout))
|
||||
|
||||
(define (readable? port)
|
||||
"Test if PORT is writable."
|
||||
(= 1 (port-poll port "r" 0)))
|
||||
|
||||
(define (writable? port)
|
||||
"Test if PORT is writable."
|
||||
(= 1 (port-poll port "w" 0)))
|
||||
|
||||
(define (make-wait-operation ready? schedule-when-ready port
|
||||
port-ready-fd this-procedure)
|
||||
(make-base-operation #f
|
||||
(lambda _
|
||||
(and (ready? port) values))
|
||||
(lambda (flag sched resume)
|
||||
(define (commit)
|
||||
(match (atomic-box-compare-and-swap! flag 'W 'S)
|
||||
('W (resume values))
|
||||
('C (commit))
|
||||
('S #f)))
|
||||
(schedule-when-ready
|
||||
sched (port-ready-fd port) commit))))
|
||||
|
||||
(define (wait-until-port-readable-operation port)
|
||||
"Make an operation that will succeed when PORT is readable."
|
||||
(unless (input-port? port)
|
||||
(error "refusing to wait forever for input on non-input port"))
|
||||
(make-wait-operation readable? schedule-task-when-fd-readable port
|
||||
port-read-wait-fd
|
||||
wait-until-port-readable-operation))
|
||||
|
||||
(define (wait-until-port-writable-operation port)
|
||||
"Make an operation that will succeed when PORT is writable."
|
||||
(unless (output-port? port)
|
||||
(error "refusing to wait forever for output on non-output port"))
|
||||
(make-wait-operation writable? schedule-task-when-fd-writable port
|
||||
port-write-wait-fd
|
||||
wait-until-port-writable-operation))
|
||||
|
||||
(define* (with-port-timeouts thunk
|
||||
#:key timeout
|
||||
(read-timeout timeout)
|
||||
(write-timeout timeout))
|
||||
(define (no-fibers-wait thunk port mode timeout)
|
||||
(define poll-timeout-ms 200)
|
||||
|
||||
;; When the GC runs, it restarts the poll syscall, but the timeout
|
||||
;; remains unchanged! When the timeout is longer than the time
|
||||
;; between the syscall restarting, I think this renders the
|
||||
;; timeout useless. Therefore, this code uses a short timeout, and
|
||||
;; repeatedly calls poll while watching the clock to see if it has
|
||||
;; timed out overall.
|
||||
(let ((timeout-internal
|
||||
(+ (get-internal-real-time)
|
||||
(* internal-time-units-per-second timeout))))
|
||||
(let loop ((poll-value
|
||||
(port-poll port mode poll-timeout-ms)))
|
||||
(if (= poll-value 0)
|
||||
(if (> (get-internal-real-time)
|
||||
timeout-internal)
|
||||
(raise-exception
|
||||
(if (string=? mode "r")
|
||||
(make-port-read-timeout-error thunk port)
|
||||
(make-port-write-timeout-error thunk port)))
|
||||
(loop (port-poll port mode poll-timeout-ms)))
|
||||
poll-value))))
|
||||
|
||||
(parameterize
|
||||
((current-read-waiter
|
||||
(lambda (port)
|
||||
(if (current-scheduler)
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wait-until-port-readable-operation port)
|
||||
(wrap-operation
|
||||
(sleep-operation read-timeout)
|
||||
(lambda ()
|
||||
(raise-exception
|
||||
(make-port-read-timeout-error thunk port))))))
|
||||
(no-fibers-wait thunk port "r" read-timeout))))
|
||||
(current-write-waiter
|
||||
(lambda (port)
|
||||
(if (current-scheduler)
|
||||
(perform-operation
|
||||
(choice-operation
|
||||
(wait-until-port-writable-operation port)
|
||||
(wrap-operation
|
||||
(sleep-operation write-timeout)
|
||||
(lambda ()
|
||||
(raise-exception
|
||||
(make-port-write-timeout-error thunk port))))))
|
||||
(no-fibers-wait thunk port "w" write-timeout)))))
|
||||
(thunk)))
|
263
knots/web-server.scm
Normal file
263
knots/web-server.scm
Normal file
|
@ -0,0 +1,263 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;; Copyright (C) 2010-2013,2015,2017 Free Software Foundation, Inc.
|
||||
|
||||
;; This library is free software; you can redistribute it and/or
|
||||
;; modify it under the terms of the GNU Lesser General Public
|
||||
;; License as published by the Free Software Foundation; either
|
||||
;; version 3 of the License, or (at your option) any later version.
|
||||
;;
|
||||
;; This library is distributed in the hope that it will be useful,
|
||||
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;; Lesser General Public License for more details.
|
||||
;;
|
||||
;; You should have received a copy of the GNU Lesser General Public License
|
||||
;; along with this program. If not, see <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots web-server)
|
||||
#:use-module (srfi srfi-9)
|
||||
#:use-module (srfi srfi-71)
|
||||
#:use-module (fibers)
|
||||
#:use-module (fibers conditions)
|
||||
#:use-module (rnrs bytevectors)
|
||||
#:use-module (ice-9 binary-ports)
|
||||
#:use-module (ice-9 textual-ports)
|
||||
#:use-module (ice-9 iconv)
|
||||
#:use-module (ice-9 match)
|
||||
#:use-module ((srfi srfi-9 gnu) #:select (set-field))
|
||||
#:use-module (system repl error-handling)
|
||||
#:use-module (web http)
|
||||
#:use-module (web request)
|
||||
#:use-module (web response)
|
||||
#:use-module (knots non-blocking)
|
||||
#:export (run-knots-web-server
|
||||
|
||||
web-server?
|
||||
web-server-socket
|
||||
web-server-port))
|
||||
|
||||
(define (make-default-socket family addr port)
|
||||
(let ((sock (socket PF_INET SOCK_STREAM 0)))
|
||||
(setsockopt sock SOL_SOCKET SO_REUSEADDR 1)
|
||||
(fcntl sock F_SETFD FD_CLOEXEC)
|
||||
(bind sock family addr port)
|
||||
sock))
|
||||
|
||||
(define (extend-response r k v . additional)
|
||||
(define (extend-alist alist k v)
|
||||
(let ((pair (assq k alist)))
|
||||
(acons k v (if pair (delq pair alist) alist))))
|
||||
(let ((r (set-field r (response-headers)
|
||||
(extend-alist (response-headers r) k v))))
|
||||
(if (null? additional)
|
||||
r
|
||||
(apply extend-response r additional))))
|
||||
|
||||
;; -> response body
|
||||
(define (sanitize-response request response body)
|
||||
"\"Sanitize\" the given response and body, making them appropriate for
|
||||
the given request.
|
||||
|
||||
As a convenience to web handler authors, RESPONSE may be given as
|
||||
an alist of headers, in which case it is used to construct a default
|
||||
response. Ensures that the response version corresponds to the request
|
||||
version. If BODY is a string, encodes the string to a bytevector,
|
||||
in an encoding appropriate for RESPONSE. Adds a
|
||||
‘content-length’ and ‘content-type’ header, as necessary.
|
||||
|
||||
If BODY is a procedure, it is called with a port as an argument,
|
||||
and the output collected as a bytevector. In the future we might try to
|
||||
instead use a compressing, chunk-encoded port, and call this procedure
|
||||
later, in the write-client procedure. Authors are advised not to rely
|
||||
on the procedure being called at any particular time."
|
||||
(cond
|
||||
((list? response)
|
||||
(sanitize-response request
|
||||
(build-response #:version (request-version request)
|
||||
#:headers response)
|
||||
body))
|
||||
((not (equal? (request-version request) (response-version response)))
|
||||
(sanitize-response request
|
||||
(adapt-response-version response
|
||||
(request-version request))
|
||||
body))
|
||||
((not body)
|
||||
(values response #vu8()))
|
||||
((string? body)
|
||||
(let* ((type (response-content-type response
|
||||
'(text/plain)))
|
||||
(declared-charset (assq-ref (cdr type) 'charset))
|
||||
(charset (or declared-charset "utf-8")))
|
||||
(sanitize-response
|
||||
request
|
||||
(if declared-charset
|
||||
response
|
||||
(extend-response response 'content-type
|
||||
`(,@type (charset . ,charset))))
|
||||
(string->bytevector body charset))))
|
||||
((not (or (bytevector? body)
|
||||
(procedure? body)))
|
||||
(error "unexpected body type"))
|
||||
((and (response-must-not-include-body? response)
|
||||
body
|
||||
;; FIXME make this stricter: even an empty body should be prohibited.
|
||||
(not (zero? (bytevector-length body))))
|
||||
(error "response with this status code must not include body" response))
|
||||
(else
|
||||
;; check length; assert type; add other required fields?
|
||||
(values (if (procedure? body)
|
||||
(if (response-content-length response)
|
||||
response
|
||||
(extend-response response
|
||||
'transfer-encoding
|
||||
'((chunked))))
|
||||
(let ((rlen (response-content-length response))
|
||||
(blen (bytevector-length body)))
|
||||
(cond
|
||||
(rlen (if (= rlen blen)
|
||||
response
|
||||
(error "bad content-length" rlen blen)))
|
||||
(else (extend-response response 'content-length blen)))))
|
||||
(if (eq? (request-method request) 'HEAD)
|
||||
;; Responses to HEAD requests must not include bodies.
|
||||
;; We could raise an error here, but it seems more
|
||||
;; appropriate to just do something sensible.
|
||||
#f
|
||||
body)))))
|
||||
|
||||
(define (with-stack-and-prompt thunk)
|
||||
(call-with-prompt (default-prompt-tag)
|
||||
(lambda () (start-stack #t (thunk)))
|
||||
(lambda (k proc)
|
||||
(with-stack-and-prompt (lambda () (proc k))))))
|
||||
|
||||
(define (keep-alive? response)
|
||||
(let ((v (response-version response)))
|
||||
(and (or (< (response-code response) 400)
|
||||
(= (response-code response) 404))
|
||||
(case (car v)
|
||||
((1)
|
||||
(case (cdr v)
|
||||
((1) (not (memq 'close (response-connection response))))
|
||||
((0) (memq 'keep-alive (response-connection response)))))
|
||||
(else #f)))))
|
||||
|
||||
(define (handle-request handler client)
|
||||
(let ((request
|
||||
(catch #t
|
||||
(lambda ()
|
||||
(read-request client))
|
||||
(lambda (key . args)
|
||||
(display "While reading request:\n" (current-error-port))
|
||||
(print-exception (current-error-port) #f key args)
|
||||
#f))))
|
||||
(let ((response
|
||||
body
|
||||
(cond
|
||||
((not request)
|
||||
;; Bad request.
|
||||
(values (build-response #:version '(1 . 0) #:code 400
|
||||
#:headers '((content-length . 0)))
|
||||
#vu8()))
|
||||
(else
|
||||
(call-with-error-handling
|
||||
(lambda ()
|
||||
(call-with-values (lambda ()
|
||||
(with-stack-and-prompt
|
||||
(lambda ()
|
||||
(handler request))))
|
||||
(lambda (response body)
|
||||
(sanitize-response request response body))))
|
||||
#:on-error 'backtrace
|
||||
#:post-error (lambda _
|
||||
(values (build-response #:code 500) #f)))))))
|
||||
(write-response response client)
|
||||
(when body
|
||||
(if (procedure? body)
|
||||
(if (response-content-length response)
|
||||
(body client)
|
||||
(let ((chunked-port
|
||||
(make-chunked-output-port client
|
||||
#:keep-alive? #t)))
|
||||
(body chunked-port)
|
||||
(close-port chunked-port)))
|
||||
(put-bytevector client body)))
|
||||
(force-output client)
|
||||
|
||||
(keep-alive? response))))
|
||||
|
||||
(define (client-loop client handler)
|
||||
;; Always disable Nagle's algorithm, as we handle buffering
|
||||
;; ourselves; when we force-output, we really want the data to go
|
||||
;; out.
|
||||
(setvbuf client 'block 1024)
|
||||
(setsockopt client IPPROTO_TCP TCP_NODELAY 1)
|
||||
(with-throw-handler #t
|
||||
(lambda ()
|
||||
(let loop ()
|
||||
(cond
|
||||
((catch #t
|
||||
(lambda () (eof-object? (lookahead-u8 client)))
|
||||
(lambda _ #t))
|
||||
(close-port client))
|
||||
(else
|
||||
(let ((keep-alive? (handle-request handler client)))
|
||||
(if keep-alive?
|
||||
(loop)
|
||||
(close-port client)))))))
|
||||
(lambda (k . args)
|
||||
(close-port client))))
|
||||
|
||||
(define-record-type <web-server>
|
||||
(make-web-server socket port)
|
||||
web-server?
|
||||
(socket web-server-socket)
|
||||
(port web-server-port))
|
||||
|
||||
(define* (run-knots-web-server handler #:key
|
||||
(host #f)
|
||||
(family AF_INET)
|
||||
(addr (if host
|
||||
(inet-pton family host)
|
||||
INADDR_LOOPBACK))
|
||||
(port 8080)
|
||||
(socket (make-default-socket family addr port)))
|
||||
"Run the fibers web server.
|
||||
|
||||
HANDLER should be a procedure that takes one argument, the HTTP
|
||||
request and returns two values, the response and response body.
|
||||
|
||||
For example, here is a simple \"Hello, World!\" server:
|
||||
|
||||
@example
|
||||
(define (handler request)
|
||||
(let ((body (read-request-body request)))
|
||||
(values '((content-type . (text/plain)))
|
||||
\"Hello, World!\")))
|
||||
(run-server handler)
|
||||
@end example
|
||||
|
||||
The response and body will be run through ‘sanitize-response’
|
||||
before sending back to the client."
|
||||
(non-blocking-port socket)
|
||||
;; We use a large backlog by default. If the server is suddenly hit
|
||||
;; with a number of connections on a small backlog, clients won't
|
||||
;; receive confirmation for their SYN, leading them to retry --
|
||||
;; probably successfully, but with a large latency.
|
||||
(listen socket 1024)
|
||||
(sigaction SIGPIPE SIG_IGN)
|
||||
|
||||
(spawn-fiber
|
||||
(lambda ()
|
||||
(let loop ()
|
||||
(match (accept socket (logior SOCK_NONBLOCK SOCK_CLOEXEC))
|
||||
((client . sockaddr)
|
||||
(spawn-fiber (lambda ()
|
||||
(client-loop client handler))
|
||||
#:parallel? #t)
|
||||
(loop))))))
|
||||
|
||||
(make-web-server socket
|
||||
(vector-ref (getsockname socket)
|
||||
2))) ; Not sure what this structure is
|
577
knots/worker-threads.scm
Normal file
577
knots/worker-threads.scm
Normal file
|
@ -0,0 +1,577 @@
|
|||
;;; Guile Knots
|
||||
;;; Copyright © 2020 Christopher Baines <mail@cbaines.net>
|
||||
;;;
|
||||
;;; This file is part of Guile Knots.
|
||||
;;;
|
||||
;;; The Guile Knots is free software; you can redistribute it and/or
|
||||
;;; modify it under the terms of the GNU General Public License as
|
||||
;;; published by the Free Software Foundation; either version 3 of the
|
||||
;;; License, or (at your option) any later version.
|
||||
;;;
|
||||
;;; The Guile Knots is distributed in the hope that it will be useful,
|
||||
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
;;; General Public License for more details.
|
||||
;;;
|
||||
;;; You should have received a copy of the GNU General Public License
|
||||
;;; along with the guix-data-service. If not, see
|
||||
;;; <http://www.gnu.org/licenses/>.
|
||||
|
||||
(define-module (knots worker-threads)
|
||||
#:use-module (srfi srfi-1)
|
||||
#:use-module (srfi srfi-19)
|
||||
#:use-module (srfi srfi-71)
|
||||
#:use-module (system foreign)
|
||||
#:use-module (system base target)
|
||||
#:use-module (rnrs bytevectors)
|
||||
#:use-module (ice-9 q)
|
||||
#:use-module (ice-9 match)
|
||||
#:use-module (ice-9 threads)
|
||||
#:use-module (fibers)
|
||||
#:use-module (fibers timers)
|
||||
#:use-module (fibers channels)
|
||||
#:use-module (fibers operations)
|
||||
#:export (set-thread-name
|
||||
thread-name
|
||||
|
||||
make-worker-thread-channel
|
||||
call-with-worker-thread
|
||||
|
||||
&worker-thread-timeout
|
||||
worker-thread-timeout-error?
|
||||
|
||||
%worker-thread-default-timeout
|
||||
|
||||
create-work-queue))
|
||||
|
||||
(define* (syscall->procedure return-type name argument-types
|
||||
#:key library)
|
||||
"Return a procedure that wraps the C function NAME using the dynamic FFI,
|
||||
and that returns two values: NAME's return value, and errno. When LIBRARY is
|
||||
specified, look up NAME in that library rather than in the global symbol name
|
||||
space.
|
||||
|
||||
If an error occurs while creating the binding, defer the error report until
|
||||
the returned procedure is called."
|
||||
(catch #t
|
||||
(lambda ()
|
||||
;; Note: When #:library is set, try it first and fall back to libc
|
||||
;; proper. This is because libraries like libutil.so have been subsumed
|
||||
;; by libc.so with glibc >= 2.34.
|
||||
(let ((ptr (dynamic-func name
|
||||
(if library
|
||||
(or (false-if-exception
|
||||
(dynamic-link library))
|
||||
(dynamic-link))
|
||||
(dynamic-link)))))
|
||||
;; The #:return-errno? facility was introduced in Guile 2.0.12.
|
||||
(pointer->procedure return-type ptr argument-types
|
||||
#:return-errno? #t)))
|
||||
(lambda args
|
||||
(lambda _
|
||||
(throw 'system-error name "~A" (list (strerror ENOSYS))
|
||||
(list ENOSYS))))))
|
||||
|
||||
(define %prctl
|
||||
;; Should it win the API contest against 'ioctl'? You tell us!
|
||||
(syscall->procedure int "prctl"
|
||||
(list int unsigned-long unsigned-long
|
||||
unsigned-long unsigned-long)))
|
||||
|
||||
(define PR_SET_NAME 15) ;<linux/prctl.h>
|
||||
(define PR_GET_NAME 16)
|
||||
(define PR_SET_CHILD_SUBREAPER 36)
|
||||
|
||||
(define (set-child-subreaper!)
|
||||
"Set the CHILD_SUBREAPER capability for the current process."
|
||||
(%prctl PR_SET_CHILD_SUBREAPER 1 0 0 0))
|
||||
|
||||
(define %max-thread-name-length
|
||||
;; Maximum length in bytes of the process name, including the terminating
|
||||
;; zero.
|
||||
16)
|
||||
|
||||
(define (set-thread-name!/linux name)
|
||||
"Set the name of the calling thread to NAME. NAME is truncated to 15
|
||||
bytes."
|
||||
(let ((ptr (string->pointer name)))
|
||||
(let ((ret
|
||||
err
|
||||
(%prctl PR_SET_NAME
|
||||
(pointer-address ptr) 0 0 0)))
|
||||
(unless (zero? ret)
|
||||
(throw 'set-process-name "set-process-name"
|
||||
"set-process-name: ~A"
|
||||
(list (strerror err))
|
||||
(list err))))))
|
||||
|
||||
(define (bytes->string bytes)
|
||||
"Read BYTES, a list of bytes, and return the null-terminated string decoded
|
||||
from there, or #f if that would be an empty string."
|
||||
(match (take-while (negate zero?) bytes)
|
||||
(()
|
||||
#f)
|
||||
(non-zero
|
||||
(list->string (map integer->char non-zero)))))
|
||||
|
||||
(define (thread-name/linux)
|
||||
"Return the name of the calling thread as a string."
|
||||
(let ((buf (make-bytevector %max-thread-name-length)))
|
||||
(let ((ret
|
||||
err
|
||||
(%prctl PR_GET_NAME
|
||||
(pointer-address (bytevector->pointer buf))
|
||||
0 0 0)))
|
||||
(if (zero? ret)
|
||||
(bytes->string (bytevector->u8-list buf))
|
||||
(throw 'process-name "process-name"
|
||||
"process-name: ~A"
|
||||
(list (strerror err))
|
||||
(list err))))))
|
||||
|
||||
(define set-thread-name
|
||||
(if (string-contains %host-type "linux")
|
||||
set-thread-name!/linux
|
||||
(const #f)))
|
||||
|
||||
(define thread-name
|
||||
(if (string-contains %host-type "linux")
|
||||
thread-name/linux
|
||||
(const "")))
|
||||
|
||||
(define %worker-thread-args
|
||||
(make-parameter #f))
|
||||
|
||||
(define* (make-worker-thread-channel initializer
|
||||
#:key (parallelism 1)
|
||||
(delay-logger (lambda _ #f))
|
||||
(duration-logger (const #f))
|
||||
destructor
|
||||
lifetime
|
||||
(log-exception? (const #t))
|
||||
(expire-on-exception? #f)
|
||||
(name "unnamed"))
|
||||
"Return a channel used to offload work to a dedicated thread. ARGS are the
|
||||
arguments of the worker thread procedure."
|
||||
(define thread-proc-vector
|
||||
(make-vector parallelism #f))
|
||||
|
||||
(define (initializer/safe)
|
||||
(let ((args
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"exception running initializer in worker thread (~A): ~A:\n ~A\n"
|
||||
name
|
||||
initializer
|
||||
exn)
|
||||
#f)
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
initializer
|
||||
(lambda args
|
||||
(backtrace))))
|
||||
#:unwind? #t)))
|
||||
|
||||
(if args
|
||||
args
|
||||
;; never give up, just keep retrying
|
||||
(begin
|
||||
(sleep 1)
|
||||
(initializer/safe)))))
|
||||
|
||||
(define (destructor/safe args)
|
||||
(let ((success?
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"exception running destructor in worker thread (~A): ~A:\n ~A\n"
|
||||
name
|
||||
destructor
|
||||
exn)
|
||||
#f)
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
(lambda ()
|
||||
(apply destructor args)
|
||||
#t)
|
||||
(lambda _
|
||||
(backtrace))))
|
||||
#:unwind? #t)))
|
||||
|
||||
(or success?
|
||||
#t
|
||||
(begin
|
||||
(sleep 1)
|
||||
(destructor/safe args)))))
|
||||
|
||||
(define (process thread-index channel args)
|
||||
(let loop ((current-lifetime lifetime))
|
||||
(let ((exception?
|
||||
(match (get-message channel)
|
||||
(((? channel? reply) sent-time (? procedure? proc))
|
||||
(let ((time-delay
|
||||
(- (get-internal-real-time)
|
||||
sent-time)))
|
||||
(delay-logger (/ time-delay
|
||||
internal-time-units-per-second))
|
||||
|
||||
(let* ((start-time (get-internal-real-time))
|
||||
(response
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(list 'worker-thread-error
|
||||
(/ (- (get-internal-real-time)
|
||||
start-time)
|
||||
internal-time-units-per-second)
|
||||
exn))
|
||||
(lambda ()
|
||||
(vector-set! thread-proc-vector
|
||||
thread-index
|
||||
proc)
|
||||
(with-throw-handler #t
|
||||
(lambda ()
|
||||
(call-with-values
|
||||
(lambda ()
|
||||
(start-stack
|
||||
'worker-thread
|
||||
(apply proc args)))
|
||||
(lambda vals
|
||||
(cons (/ (- (get-internal-real-time)
|
||||
start-time)
|
||||
internal-time-units-per-second)
|
||||
vals))))
|
||||
(lambda args
|
||||
(when (match args
|
||||
(('%exception exn)
|
||||
(log-exception? exn))
|
||||
(_ #t))
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"worker-thread: exception: ~A\n" args)
|
||||
(backtrace)))))
|
||||
#:unwind? #t)))
|
||||
(put-message reply
|
||||
response)
|
||||
|
||||
(vector-set! thread-proc-vector
|
||||
thread-index
|
||||
#f)
|
||||
|
||||
(match response
|
||||
(('worker-thread-error duration _)
|
||||
(when duration-logger
|
||||
(duration-logger duration proc))
|
||||
#t)
|
||||
((duration . _)
|
||||
(when duration-logger
|
||||
(duration-logger duration proc))
|
||||
#f))))))))
|
||||
(unless (and expire-on-exception?
|
||||
exception?)
|
||||
(if (number? current-lifetime)
|
||||
(unless (< current-lifetime 0)
|
||||
(loop (if current-lifetime
|
||||
(- current-lifetime 1)
|
||||
#f)))
|
||||
(loop #f))))))
|
||||
|
||||
(let ((channel (make-channel)))
|
||||
(for-each
|
||||
(lambda (thread-index)
|
||||
(call-with-new-thread
|
||||
(lambda ()
|
||||
(catch 'system-error
|
||||
(lambda ()
|
||||
(set-thread-name
|
||||
(string-append
|
||||
name " w t "
|
||||
(number->string thread-index))))
|
||||
(const #t))
|
||||
|
||||
(let init ((args (initializer/safe)))
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"worker-thread-channel: exception: ~A\n" exn))
|
||||
(lambda ()
|
||||
(parameterize ((%worker-thread-args args))
|
||||
(process thread-index channel args)))
|
||||
#:unwind? #t)
|
||||
|
||||
(when destructor
|
||||
(destructor/safe args))
|
||||
|
||||
(init (initializer/safe))))))
|
||||
(iota parallelism))
|
||||
|
||||
(values channel
|
||||
thread-proc-vector)))
|
||||
|
||||
(define &worker-thread-timeout
|
||||
(make-exception-type '&worker-thread-timeout
|
||||
&error
|
||||
'()))
|
||||
|
||||
(define make-worker-thread-timeout-error
|
||||
(record-constructor &worker-thread-timeout))
|
||||
|
||||
(define worker-thread-timeout-error?
|
||||
(record-predicate &worker-thread-timeout))
|
||||
|
||||
(define %worker-thread-default-timeout
|
||||
(make-parameter 30))
|
||||
|
||||
(define* (call-with-worker-thread channel proc #:key duration-logger
|
||||
(timeout (%worker-thread-default-timeout)))
|
||||
"Send PROC to the worker thread through CHANNEL. Return the result of PROC.
|
||||
If already in the worker thread, call PROC immediately."
|
||||
(let ((args (%worker-thread-args)))
|
||||
(if args
|
||||
(apply proc args)
|
||||
(let* ((reply (make-channel))
|
||||
(operation-success?
|
||||
(perform-operation
|
||||
(let ((put
|
||||
(wrap-operation
|
||||
(put-operation channel
|
||||
(list reply
|
||||
(get-internal-real-time)
|
||||
proc))
|
||||
(const #t))))
|
||||
|
||||
(if timeout
|
||||
(choice-operation
|
||||
put
|
||||
(wrap-operation (sleep-operation timeout)
|
||||
(const #f)))
|
||||
put)))))
|
||||
|
||||
(unless operation-success?
|
||||
(raise-exception
|
||||
(make-worker-thread-timeout-error)))
|
||||
|
||||
(match (get-message reply)
|
||||
(('worker-thread-error duration exn)
|
||||
(when duration-logger
|
||||
(duration-logger duration))
|
||||
(raise-exception exn))
|
||||
((duration . result)
|
||||
(when duration-logger
|
||||
(duration-logger duration))
|
||||
(apply values result)))))))
|
||||
|
||||
(define* (create-work-queue thread-count-parameter proc
|
||||
#:key thread-start-delay
|
||||
(thread-stop-delay
|
||||
(make-time time-duration 0 0))
|
||||
(name "unnamed")
|
||||
priority<?)
|
||||
(let ((queue (make-q))
|
||||
(queue-mutex (make-mutex))
|
||||
(job-available (make-condition-variable))
|
||||
(running-job-args (make-hash-table)))
|
||||
|
||||
(define get-thread-count
|
||||
(cond
|
||||
((number? thread-count-parameter)
|
||||
(const thread-count-parameter))
|
||||
((eq? thread-count-parameter #f)
|
||||
;; Run one thread per job
|
||||
(lambda ()
|
||||
(+ (q-length queue)
|
||||
(hash-count (lambda (index val)
|
||||
(list? val))
|
||||
running-job-args))))
|
||||
(else
|
||||
thread-count-parameter)))
|
||||
|
||||
(define process-job
|
||||
(if priority<?
|
||||
(lambda* (args #:key priority)
|
||||
(with-mutex queue-mutex
|
||||
(enq! queue (cons priority args))
|
||||
(set-car!
|
||||
queue
|
||||
(stable-sort! (car queue)
|
||||
(lambda (a b)
|
||||
(priority<?
|
||||
(car a)
|
||||
(car b)))))
|
||||
(sync-q! queue)
|
||||
(start-new-threads-if-necessary (get-thread-count))
|
||||
(signal-condition-variable job-available)))
|
||||
(lambda args
|
||||
(with-mutex queue-mutex
|
||||
(enq! queue args)
|
||||
(start-new-threads-if-necessary (get-thread-count))
|
||||
(signal-condition-variable job-available)))))
|
||||
|
||||
(define (count-threads)
|
||||
(with-mutex queue-mutex
|
||||
(hash-count (const #t) running-job-args)))
|
||||
|
||||
(define (count-jobs)
|
||||
(with-mutex queue-mutex
|
||||
(+ (q-length queue)
|
||||
(hash-count (lambda (index val)
|
||||
(list? val))
|
||||
running-job-args))))
|
||||
|
||||
(define (list-jobs)
|
||||
(with-mutex queue-mutex
|
||||
(append (if priority<?
|
||||
(map cdr (car queue))
|
||||
(list-copy (car queue)))
|
||||
(hash-fold (lambda (key val result)
|
||||
(if val
|
||||
(cons val result)
|
||||
result))
|
||||
'()
|
||||
running-job-args))))
|
||||
|
||||
(define (thread-process-job job-args)
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
(simple-format (current-error-port)
|
||||
"~A work queue, job raised exception ~A: ~A\n"
|
||||
name job-args exn))
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
(lambda ()
|
||||
(apply proc job-args))
|
||||
(lambda (key . args)
|
||||
(simple-format
|
||||
(current-error-port)
|
||||
"~A work queue, exception when handling job: ~A ~A\n"
|
||||
name key args)
|
||||
(backtrace))))
|
||||
#:unwind? #t))
|
||||
|
||||
(define (start-thread thread-index)
|
||||
(define (too-many-threads?)
|
||||
(let ((running-jobs-count
|
||||
(hash-count (lambda (index val)
|
||||
(list? val))
|
||||
running-job-args))
|
||||
(desired-thread-count (get-thread-count)))
|
||||
|
||||
(>= running-jobs-count
|
||||
desired-thread-count)))
|
||||
|
||||
(define (thread-idle-for-too-long? last-job-finished-at)
|
||||
(time>=?
|
||||
(time-difference (current-time time-monotonic)
|
||||
last-job-finished-at)
|
||||
thread-stop-delay))
|
||||
|
||||
(define (stop-thread)
|
||||
(hash-remove! running-job-args
|
||||
thread-index)
|
||||
(unlock-mutex queue-mutex))
|
||||
|
||||
(call-with-new-thread
|
||||
(lambda ()
|
||||
(catch 'system-error
|
||||
(lambda ()
|
||||
(set-thread-name
|
||||
(string-append name " q t "
|
||||
(number->string thread-index))))
|
||||
(const #t))
|
||||
|
||||
(let loop ((last-job-finished-at (current-time time-monotonic)))
|
||||
(lock-mutex queue-mutex)
|
||||
|
||||
(if (too-many-threads?)
|
||||
(stop-thread)
|
||||
(let ((job-args
|
||||
(if (q-empty? queue)
|
||||
;; #f from wait-condition-variable indicates a timeout
|
||||
(if (wait-condition-variable
|
||||
job-available
|
||||
queue-mutex
|
||||
(+ 9 (time-second (current-time))))
|
||||
;; Another thread could have taken
|
||||
;; the job in the mean time
|
||||
(if (q-empty? queue)
|
||||
#f
|
||||
(if priority<?
|
||||
(cdr (deq! queue))
|
||||
(deq! queue)))
|
||||
#f)
|
||||
(if priority<?
|
||||
(cdr (deq! queue))
|
||||
(deq! queue)))))
|
||||
|
||||
(if job-args
|
||||
(begin
|
||||
(hash-set! running-job-args
|
||||
thread-index
|
||||
job-args)
|
||||
|
||||
(unlock-mutex queue-mutex)
|
||||
(thread-process-job job-args)
|
||||
|
||||
(with-mutex queue-mutex
|
||||
(hash-set! running-job-args
|
||||
thread-index
|
||||
#f))
|
||||
|
||||
(loop (current-time time-monotonic)))
|
||||
(if (thread-idle-for-too-long? last-job-finished-at)
|
||||
(stop-thread)
|
||||
(begin
|
||||
(unlock-mutex queue-mutex)
|
||||
|
||||
(loop last-job-finished-at))))))))))
|
||||
|
||||
|
||||
(define start-new-threads-if-necessary
|
||||
(let ((previous-thread-started-at (make-time time-monotonic 0 0)))
|
||||
(lambda (desired-count)
|
||||
(let* ((thread-count
|
||||
(hash-count (const #t) running-job-args))
|
||||
(threads-to-start
|
||||
(- desired-count thread-count)))
|
||||
(when (> threads-to-start 0)
|
||||
(for-each
|
||||
(lambda (thread-index)
|
||||
(when (eq? (hash-ref running-job-args
|
||||
thread-index
|
||||
'slot-free)
|
||||
'slot-free)
|
||||
(let* ((now (current-time time-monotonic))
|
||||
(elapsed (time-difference now
|
||||
previous-thread-started-at)))
|
||||
(when (or (eq? #f thread-start-delay)
|
||||
(time>=? elapsed thread-start-delay))
|
||||
(set! previous-thread-started-at now)
|
||||
(hash-set! running-job-args
|
||||
thread-index
|
||||
#f)
|
||||
(start-thread thread-index)))))
|
||||
(iota desired-count)))))))
|
||||
|
||||
(if (procedure? thread-count-parameter)
|
||||
(call-with-new-thread
|
||||
(lambda ()
|
||||
(catch 'system-error
|
||||
(lambda ()
|
||||
(set-thread-name
|
||||
(string-append name " q t")))
|
||||
(const #t))
|
||||
|
||||
(while #t
|
||||
(sleep 15)
|
||||
(with-mutex queue-mutex
|
||||
(let ((idle-threads (hash-count (lambda (index val)
|
||||
(eq? #f val))
|
||||
running-job-args)))
|
||||
(when (= 0 idle-threads)
|
||||
(start-new-threads-if-necessary (get-thread-count))))))))
|
||||
(start-new-threads-if-necessary (get-thread-count)))
|
||||
|
||||
(values process-job count-jobs count-threads list-jobs)))
|
13
pre-inst-env.in
Normal file
13
pre-inst-env.in
Normal file
|
@ -0,0 +1,13 @@
|
|||
#!/bin/sh
|
||||
|
||||
abs_top_srcdir="`cd "@abs_top_srcdir@" > /dev/null; pwd`"
|
||||
abs_top_builddir="`cd "@abs_top_builddir@" > /dev/null; pwd`"
|
||||
|
||||
GUILE_LOAD_COMPILED_PATH="$abs_top_builddir${GUILE_LOAD_COMPILED_PATH:+:}$GUILE_LOAD_COMPILED_PATH"
|
||||
GUILE_LOAD_PATH="$abs_top_builddir:$abs_top_srcdir${GUILE_LOAD_PATH:+:}:$GUILE_LOAD_PATH"
|
||||
export GUILE_LOAD_COMPILED_PATH GUILE_LOAD_PATH
|
||||
|
||||
PATH="$abs_top_builddir:$PATH"
|
||||
export PATH
|
||||
|
||||
exec "$@"
|
28
tests.scm
Normal file
28
tests.scm
Normal file
|
@ -0,0 +1,28 @@
|
|||
(define-module (tests)
|
||||
#:use-module (ice-9 exceptions)
|
||||
#:use-module (fibers)
|
||||
#:export (run-fibers-for-tests
|
||||
assert-no-heap-growth))
|
||||
|
||||
(define (run-fibers-for-tests thunk)
|
||||
(let ((result
|
||||
(run-fibers
|
||||
(lambda ()
|
||||
(with-exception-handler
|
||||
(lambda (exn)
|
||||
exn)
|
||||
(lambda ()
|
||||
(with-throw-handler #t
|
||||
thunk
|
||||
(lambda _
|
||||
(backtrace)))
|
||||
#t)
|
||||
#:unwind? #t))
|
||||
#:hz 0
|
||||
#:parallelism 1)))
|
||||
(if (exception? result)
|
||||
(raise-exception result)
|
||||
result)))
|
||||
|
||||
(define (assert-no-heap-growth thunk)
|
||||
(thunk))
|
31
tests/non-blocking.scm
Normal file
31
tests/non-blocking.scm
Normal file
|
@ -0,0 +1,31 @@
|
|||
(use-modules (tests)
|
||||
(fibers)
|
||||
(unit-test)
|
||||
(web uri)
|
||||
(web client)
|
||||
(web response)
|
||||
(knots web-server)
|
||||
(knots non-blocking))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(let* ((web-server
|
||||
(run-knots-web-server
|
||||
(lambda (request)
|
||||
(values '((content-type . (text/plain)))
|
||||
"Hello, World!"))
|
||||
#:port 0)) ;; Bind to any port
|
||||
(port
|
||||
(web-server-port web-server))
|
||||
(uri
|
||||
(build-uri 'http #:host "127.0.0.1" #:port port)))
|
||||
|
||||
|
||||
(assert-equal
|
||||
200
|
||||
(response-code
|
||||
(http-get
|
||||
uri
|
||||
#:port (nonblocking-open-socket-for-uri uri)))))))
|
||||
|
||||
(display "non-blocking test finished successfully\n")
|
15
tests/parallelism.scm
Normal file
15
tests/parallelism.scm
Normal file
|
@ -0,0 +1,15 @@
|
|||
(use-modules (tests)
|
||||
(fibers)
|
||||
(unit-test)
|
||||
(knots parallelism))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(assert-equal
|
||||
1122
|
||||
(apply + (fibers-map
|
||||
(lambda (i)
|
||||
(* 2 i))
|
||||
(iota 34))))))
|
||||
|
||||
(display "parallelism test finished successfully\n")
|
20
tests/promise.scm
Normal file
20
tests/promise.scm
Normal file
|
@ -0,0 +1,20 @@
|
|||
(use-modules (tests)
|
||||
(fibers)
|
||||
(unit-test)
|
||||
(knots parallelism)
|
||||
(knots promise))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(let ((promises
|
||||
(map (lambda (i)
|
||||
(fibers-delay
|
||||
(lambda ()
|
||||
(* i 2))))
|
||||
(iota 10))))
|
||||
|
||||
(assert-equal
|
||||
90
|
||||
(apply + (fibers-map fibers-force promises))))))
|
||||
|
||||
(display "promise test finished successfully\n")
|
22
tests/queue.scm
Normal file
22
tests/queue.scm
Normal file
|
@ -0,0 +1,22 @@
|
|||
(use-modules (tests)
|
||||
(fibers)
|
||||
(fibers channels)
|
||||
(unit-test)
|
||||
(knots queue))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(let* ((dest-channel
|
||||
(make-channel))
|
||||
(queue-channel
|
||||
(spawn-queueing-fiber dest-channel)))
|
||||
|
||||
(put-message queue-channel 1)
|
||||
(put-message queue-channel 2)
|
||||
(put-message queue-channel 3)
|
||||
|
||||
(assert-equal 1 (get-message dest-channel))
|
||||
(assert-equal 2 (get-message dest-channel))
|
||||
(assert-equal 3 (get-message dest-channel)))))
|
||||
|
||||
(display "queue test finished successfully\n")
|
18
tests/resource-pool.scm
Normal file
18
tests/resource-pool.scm
Normal file
|
@ -0,0 +1,18 @@
|
|||
(use-modules (tests)
|
||||
(fibers)
|
||||
(unit-test)
|
||||
(knots resource-pool))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(let ((resource-pool (make-resource-pool
|
||||
(lambda ()
|
||||
2)
|
||||
1)))
|
||||
(assert-equal
|
||||
(with-resource-from-pool resource-pool
|
||||
res
|
||||
res)
|
||||
2))))
|
||||
|
||||
(display "resource-pool test finished successfully\n")
|
22
tests/timeout.scm
Normal file
22
tests/timeout.scm
Normal file
|
@ -0,0 +1,22 @@
|
|||
(use-modules (tests)
|
||||
(fibers)
|
||||
(unit-test)
|
||||
(knots timeout))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(assert-equal
|
||||
1
|
||||
(with-fibers-timeout
|
||||
(const 1)
|
||||
#:timeout 10))
|
||||
|
||||
(assert-equal
|
||||
2
|
||||
(with-fibers-timeout
|
||||
(lambda ()
|
||||
(sleep 10))
|
||||
#:timeout 0.1
|
||||
#:on-timeout (const 2)))))
|
||||
|
||||
(display "timeout test finished successfully\n")
|
30
tests/web-server.scm
Normal file
30
tests/web-server.scm
Normal file
|
@ -0,0 +1,30 @@
|
|||
(use-modules (tests)
|
||||
(fibers)
|
||||
(unit-test)
|
||||
(web uri)
|
||||
(web client)
|
||||
(web response)
|
||||
(knots web-server)
|
||||
(knots non-blocking))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(let* ((web-server
|
||||
(run-knots-web-server
|
||||
(lambda (request)
|
||||
(values '((content-type . (text/plain)))
|
||||
"Hello, World!"))
|
||||
#:port 0)) ;; Bind to any port
|
||||
(port
|
||||
(web-server-port web-server))
|
||||
(uri
|
||||
(build-uri 'http #:host "127.0.0.1" #:port port)))
|
||||
|
||||
(assert-equal
|
||||
200
|
||||
(response-code
|
||||
(http-get
|
||||
uri
|
||||
#:port (nonblocking-open-socket-for-uri uri)))))))
|
||||
|
||||
(display "web-server test finished successfully\n")
|
32
tests/worker-threads.scm
Normal file
32
tests/worker-threads.scm
Normal file
|
@ -0,0 +1,32 @@
|
|||
(use-modules (tests)
|
||||
(srfi srfi-71)
|
||||
(fibers)
|
||||
(unit-test)
|
||||
(knots worker-threads))
|
||||
|
||||
(let ((worker-thread-channel
|
||||
(make-worker-thread-channel
|
||||
(const '())
|
||||
#:parallelism 2)))
|
||||
|
||||
(run-fibers-for-tests
|
||||
(lambda ()
|
||||
(assert-equal
|
||||
(call-with-worker-thread
|
||||
worker-thread-channel
|
||||
(lambda ()
|
||||
4))
|
||||
4))))
|
||||
|
||||
(let ((process-job
|
||||
count-jobs
|
||||
count-threads
|
||||
list-jobs
|
||||
(create-work-queue
|
||||
2
|
||||
(lambda (i)
|
||||
(* i 2)))))
|
||||
|
||||
(process-job 3))
|
||||
|
||||
(display "worker-threads test finished successfully\n")
|
Loading…
Add table
Add a link
Reference in a new issue