diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..810c8b7 --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +zet.dpi +*.o diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..dbbe355 --- /dev/null +++ b/LICENSE @@ -0,0 +1,661 @@ + GNU AFFERO GENERAL PUBLIC LICENSE + Version 3, 19 November 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU Affero General Public License is a free, copyleft license for +software and other kinds of works, specifically designed to ensure +cooperation with the community in the case of network server software. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. By contrast, +our General Public Licenses are 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. + + 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. + + Developers that use our General Public Licenses protect your rights +with two steps: (1) assert copyright on the software, and (2) offer +you this License which gives you legal permission to copy, distribute +and/or modify the software. + + A secondary benefit of defending all users' freedom is that +improvements made in alternate versions of the program, if they +receive widespread use, become available for other developers to +incorporate. Many developers of free software are heartened and +encouraged by the resulting cooperation. However, in the case of +software used on network servers, this result may fail to come about. +The GNU General Public License permits making a modified version and +letting the public access it on a server without ever releasing its +source code to the public. + + The GNU Affero General Public License is designed specifically to +ensure that, in such cases, the modified source code becomes available +to the community. It requires the operator of a network server to +provide the source code of the modified version running there to the +users of that server. Therefore, public use of a modified version, on +a publicly accessible server, gives the public access to the source +code of the modified version. + + An older license, called the Affero General Public License and +published by Affero, was designed to accomplish similar goals. This is +a different license, not a version of the Affero GPL, but Affero has +released a new version of the Affero GPL which permits relicensing under +this license. + + 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 Affero 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. Remote Network Interaction; Use with the GNU General Public License. + + Notwithstanding any other provision of this License, if you modify the +Program, your modified version must prominently offer all users +interacting with it remotely through a computer network (if your version +supports such interaction) an opportunity to receive the Corresponding +Source of your version by providing access to the Corresponding Source +from a network server at no charge, through some standard or customary +means of facilitating copying of software. This Corresponding Source +shall include the Corresponding Source for any work covered by version 3 +of the GNU General Public License that is incorporated pursuant to the +following paragraph. + + 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 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 work with which it is combined will remain governed by version +3 of the GNU General Public License. + + 14. Revised Versions of this License. + + The Free Software Foundation may publish revised and/or new versions of +the GNU Affero 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 Affero 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 Affero 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 Affero 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. + + + Copyright (C) + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU Affero 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 Affero General Public License for more details. + + You should have received a copy of the GNU Affero General Public License + along with this program. If not, see . + +Also add information on how to contact you by electronic and paper mail. + + If your software can interact with users remotely through a computer +network, you should also make sure that it provides a way for users to +get its source. For example, if your program is a web application, its +interface could display a "Source" link that leads users to an archive +of the code. There are many ways you could offer source, and different +solutions will be better for different programs; see section 13 for the +specific requirements. + + 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 AGPL, see +. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..c3e29c2 --- /dev/null +++ b/Makefile @@ -0,0 +1,35 @@ +NAME=zet +BIN=zet.dpi +DILLO_DIR=~/.dillo +DPI_DIR=$(DILLO_DIR)/dpi +SUNDOWN_SRC=$(wildcard sundown/*.c) +OBJ=dpi.o zet.dpi.o io.o $(SUNDOWN_SRC:c=o) +CFLAGS=-Wall -Wextra -pedantic + +all-reload: all + pkill $(BIN) + +all: $(BIN) + +$(BIN): $(OBJ) + +install: $(BIN) domainrc + mkdir -p $(DPI_DIR)/$(NAME) + cp -f $(BIN) $(DPI_DIR)/$(NAME) + +link: $(BIN) domainrc + mkdir -p $(DPI_DIR)/$(NAME) + ln -frs $(BIN) $(DPI_DIR)/$(NAME) + +domainrc: $(DILLO_DIR)/domainrc + @grep -q '^default accept$$' $< || \ + echo 'Note: Set "default accept" in $< to enable redirects' + +$(DILLO_DIR)/domainrc: + echo 'default accept' > $@ + +clean: + rm $(BIN) $(OBJ) + +uninstall: $(BIN) + rm -f $(DPI_DIR)/$(NAME)/$(BIN) diff --git a/README.md b/README.md new file mode 100644 index 0000000..845599c --- /dev/null +++ b/README.md @@ -0,0 +1,51 @@ +# dillo-zet + +Zettelkasten application for [Dillo][]. + +## Install from [git-ssb][] +``` +git clone ssb://%R1c3tDmS57iZ5G+g4UkLSWQehG/WUVLd1Y9XkTlng8Y=.sha256 dillo-zet +cd dillo-zet +make install +dpid stop +``` +You can also use `make link` instead of `make install`, to install via a symlink. + +Then visit in Dillo. + +## Usage + +- - Main page (list all notes) +- - View a note +- - Draft a new note + +Notes are identified by a string of hexadecimal characters, prefixed by a section sign ("§"). The section sign is not included in the `dpi:/zet/` URL. + +The note format is Markdown as parsed by the [sundown][] library, with some changes, e.g. to linkify dillo-zet ids, and to make it a little more like SSB markdown. + +Notes are stored as plain text files in a `~/.zet` directory. + +## Screenshot + +![dillo-zet-screenshot-invidious.png](&oLj9GQS8Acb1OJkzjBB/0GySl8/ZycZ0WGc9ptDFxFg=.sha256) + +[Dillo]: https://www.dillo.org/ +[git-ssb]: %n92DiQh7ietE+R+X/I403LQoyf2DtR3WQfCkDKlheQU=.sha256 +[sundown]: https://github.com/vmg/sundown + +## License + +Copyright 2020 Charles E. Lehner + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU Affero 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 Affero General Public License for more details. + +You should have received a copy of the GNU Affero General Public License +along with this program. If not, see . diff --git a/dpi.c b/dpi.c new file mode 100644 index 0000000..3280064 --- /dev/null +++ b/dpi.c @@ -0,0 +1,75 @@ +#include +#include +#include +#include +#include +#include +#include "dpi.h" +#include "io.h" + +int dpi_check_auth(int fd) { + char buf[30]; + char key[4], local_key[4]; + char keys[128]; + char *home; + ssize_t sz; + int rc; + rc = read_all(fd, buf, 28); + if (rc < 0) return -1; + buf[29] = '\0'; + // first byte was read already + rc = sscanf(buf, "cmd='auth' msg='%4x' '>", key); + if (rc < 1) { errno = EPROTO; return -1; } + home = getenv("HOME"); + if (!home) home = "."; + sz = read_file(keys, sizeof(keys), "%s/.dillo/dpid_comm_keys", home); + if (sz < 0) { errno = ENOKEY; return -1; } + rc = sscanf(keys, "%*d %4x", local_key); + if (rc < 1) { errno = ENOKEY; return -1; } + if (memcmp(key, local_key, 4)) { errno = EKEYREJECTED; return -1; } + return 0; +} + +int dpi_read_request(int fd, char *url_buf, size_t url_len) { + char buf[21]; + size_t len; + int rc; + int i; + + rc = read_all(fd, buf, sizeof(buf)); + if (rc < 0 && errno == EPIPE && !strncmp(buf, "", 16)) { + errno = ESHUTDOWN; + return -1; + } + if (rc < 0) return -1; + if (strncmp(buf, " len-3 || strncmp(url_buf + i, "' '>", 4)) { + errno = EPROTO; + return -1; + } + url_buf[i] = '\0'; + return 0; +} + +int dpi_send_status(int fd, const char *status) { + return dprintf(fd, "", status); +} + +int dpi_send_header(int fd, const char *content_type) { + return dprintf(fd, "" + "Content-Type: %s\n\n", content_type); +} + +int dpi_reload(int fd) { + return dprintf(fd, ""); +} diff --git a/dpi.h b/dpi.h new file mode 100644 index 0000000..bb06cb5 --- /dev/null +++ b/dpi.h @@ -0,0 +1,9 @@ +#pragma once + +#include + +int dpi_check_auth(int fd); +int dpi_read_request(int fd, char *url_buf, size_t url_len); +int dpi_send_status(int fd, const char *status); +int dpi_send_header(int fd, const char *content_type); +int dpi_reload(int fd); diff --git a/io.c b/io.c new file mode 100644 index 0000000..2754744 --- /dev/null +++ b/io.c @@ -0,0 +1,112 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +#include "io.h" + +int read_all(int fd, unsigned char *buf, size_t len) { + ssize_t nbytes; + while (len > 0) { + nbytes = read(fd, buf, len); + if (nbytes == 0) { errno = EPIPE; return -1; } + if (nbytes < 0 && errno == EINTR) continue; + if (nbytes < 0) return -1; + buf += nbytes; + len -= nbytes; + } + return 0; +} + +int read_some(int fd, unsigned char *buf, size_t *lenp) { + ssize_t nbytes; + do nbytes = read(fd, buf, *lenp); + while (nbytes < 0 && errno == EINTR); + if (nbytes == 0) { errno = EPIPE; return -1; } + if (nbytes < 0) return -1; + *lenp = nbytes; + return 0; +} + +int read_char(int fd) { + ssize_t nbytes; + char buf[1]; + do nbytes = read(fd, buf, 1); + while (nbytes < 0 && errno == EINTR); + if (nbytes < 0) return -1; + if (nbytes == 0) { errno = EPIPE; return -1; } + return buf[0]; +} + +int write_all(int fd, const unsigned char *buf, size_t count) { + ssize_t nbytes; + while (count > 0) { + nbytes = write(fd, buf, count); + if (nbytes < 0 && errno == EINTR) continue; + if (nbytes < 0) return -1; + buf += nbytes; + count -= nbytes; + } + return 0; +} + +int write_char(int fd, char c) { + ssize_t nbytes; + char buf[1] = {c}; + do nbytes = write(fd, buf, 1); + while (nbytes < 0 && errno == EINTR); + if (nbytes < 0) return -1; + if (nbytes == 0) { errno = EPIPE; return -1; } + return 0; +} + +ssize_t read_file(char *buf, size_t len, const char *fmt, ...) { + va_list ap; + int rc; + struct stat st; + int fd; + + va_start(ap, fmt); + rc = vsnprintf(buf, len, fmt, ap); + va_end(ap); + if (rc < 0) return -1; + if ((size_t)rc >= len) { errno = ENAMETOOLONG; return -1; } + + rc = stat(buf, &st); + if (rc < 0) return -1; + if ((size_t)st.st_size > len-1) { errno = EMSGSIZE; return -1; } + + fd = open(buf, O_RDONLY); + if (fd < 0) return -1; + + rc = read_all(fd, (unsigned char *)buf, st.st_size); + if (rc < 0) return -1; + + buf[(size_t)st.st_size] = '\0'; + + close(fd); + return st.st_size; +} + +char *read_full(int fd) { + int rc; + struct stat st; + + rc = fstat(fd, &st); + if (rc < 0) return NULL; + + char *buf = malloc(st.st_size + 1); + if (buf == NULL) return NULL; + + rc = read_all(fd, (unsigned char *)buf, st.st_size); + if (rc < 0) return NULL; + + buf[(size_t)st.st_size] = '\0'; + + close(fd); + return buf; +} diff --git a/io.h b/io.h new file mode 100644 index 0000000..ecc1ca0 --- /dev/null +++ b/io.h @@ -0,0 +1,14 @@ +#pragma once + +#include + +#define write_buf(fd, buf) \ + write_all(fd, (unsigned const char *)buf, sizeof(buf)-1) + +int read_all(int fd, unsigned char *buf, size_t count); +int read_some(int fd, unsigned char *buf, size_t *lenp); +int read_char(int fd); +ssize_t read_file(char *buf, size_t len, const char *fmt, ...); +int write_all(int fd, unsigned const char *buf, size_t count); +int write_char(int fd, char c); +char *read_full(int fd); diff --git a/zet.dpi.c b/zet.dpi.c new file mode 100644 index 0000000..f91d842 --- /dev/null +++ b/zet.dpi.c @@ -0,0 +1,945 @@ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "dpi.h" +#include "io.h" +#include "sundown/markdown.h" +#include "sundown/html.h" +#include "sundown/buffer.h" +#include "sundown/houdini.h" + +#define NAV_ALL "All" +#define NAV_NEW "New" +#define STRONG(html) "" html "" + +#define TOPBAR_NAV NAV_ALL " " NAV_NEW " " +#define TOPBAR_NAV_ALL STRONG(NAV_ALL) " " NAV_NEW " " +#define TOPBAR_NAV_NEW NAV_ALL " " STRONG(NAV_NEW) " " + +static const size_t sigil_size = sizeof("§")-1; +static const int id_length = 16; + +static const int max_cols = 40; + +static char server_hostname[256]; +static char server_url[256]; +static char zet_dir[_POSIX_PATH_MAX-64]; + +struct http_request { + char *method; + char *path; + char *query; + char *hash; + char *http_version; + char *host; + char *referer; + ssize_t content_length; + char *content_type; + char *multipart_boundary; + int fd; + char *data, *full_data; + size_t len; +}; + +struct zet_search { + DIR *dir; + char *id; +}; + +static int count_lines_in(const char *str) { + int count = 0; + char c; + int col = 0; + while ((c = *str++)) { + if (c == '\n' || col++ > max_cols) { + count++; + col = 0; + } + } + return count; +} + +static int count_lines(int fd) { + int count = 0; + do { + unsigned char buf[4096]; + size_t len = sizeof(buf)-1; + int rc = read_some(fd, buf, &len); + if (rc < 0) { + if (errno == EPIPE) break; + return -1; + } + buf[len] = '\0'; + count += count_lines_in((char *)buf); + } while (1); + return count; +} + +static int write_html_char(int fd, char c) { + switch (c) { + case '&': return write_buf(fd, "&"); + case '<': return write_buf(fd, "<"); + case '>': return write_buf(fd, ">"); + case '"': return write_buf(fd, """); + } + return write_char(fd, c); +} + +static int write_html(int fd, const char *buf, size_t len) { + while (len > 0) { + // note: buf must null-terminated + char *next = strpbrk(buf, "&<>\""); + if (next == NULL) return write_all(fd, (unsigned char *)buf, len); + char c = *next; + size_t sublen = next - buf; + int rc = write_all(fd, (unsigned char *)buf, sublen); + if (rc < 0) return -1; + buf += sublen + 1; + len -= sublen + 1; + rc = write_html_char(fd, c); + if (rc < 0) return -1; + } + return 0; +} + +static int passthrough_note_html(int fd, int note_fd) { + int rc; + do { + unsigned char buf[4096]; + size_t len = sizeof(buf)-1; + rc = read_some(note_fd, buf, &len); + if (rc < 0) { + if (errno != EPIPE) dprintf(fd, + "\nError: %s", strerror(errno)); + break; + } + buf[len] = '\0'; + rc = write_html(fd, (char *)buf, len); + if (rc < 0) warn("write_html"); + } while (rc == 0); + return 0; +} + +static int dpi_respond_err(int fd, const char *fmt, ...) { + int rc; + va_list ap; + int err = errno; + va_start(ap, fmt); + rc = dpi_send_header(fd, "text/plain"); + rc |= vdprintf(fd, fmt, ap); + rc |= dprintf(fd, ": %s", strerror(err)); + va_end(ap); + rc |= close(fd); + return rc; +} + +static char *zet_get_title(const char *id, char *buf, size_t len) { + char path_buf[_POSIX_PATH_MAX]; + ssize_t sz = snprintf(path_buf, sizeof(path_buf), "%s/%s", zet_dir, id); + if (sz < 0 || (size_t)sz >= sizeof(path_buf)) return NULL; + int fd = open(path_buf, O_RDONLY); + if (fd < 0) return NULL; + int rc = read_some(fd, (unsigned char *)buf, &len); + if (rc < 0) { close(fd); return NULL; } + buf[len] = '\0'; + char *end = strchr(buf, '\n'); + if (end != NULL) *end = '\0'; + close(fd); + while (*buf == '#') buf++; + while (*buf == ' ') buf++; + return buf; +} + +static char *zet_get_buf_title(const struct buf *link, char *buf, size_t len) { + char id_buf[128]; + strncpy(id_buf, link->data, link->size); + id_buf[sizeof(id_buf)-1] = '\0'; + return zet_get_title(id_buf + sigil_size, buf, len); +} + +static int zet_links_in(const char *str, const char *id_to) { + while (1) { + str = strstr(str, "§"); + if (str == NULL) return 0; + str += sigil_size; + if (!strncmp(str, id_to, id_length)) return 1; + } + return 0; +} + +static int zet_links_to(const char *id_from, const char *id_to) { + // TODO: index links, so that every source file doesn't have to be read all + // the time + int rc; + char path_buf[_POSIX_PATH_MAX]; + ssize_t sz = snprintf(path_buf, sizeof(path_buf), "%s/%s", zet_dir, id_from); + if (sz < 0 || (size_t)sz >= sizeof(path_buf)) return -1; + int fd = open(path_buf, O_RDONLY); + if (fd < 0) return -1; + size_t fringe = 0; + size_t link_len = strlen(id_to) + id_length; + unsigned char buf[4096]; + do { + size_t len = sizeof(buf)-fringe-1; + rc = read_some(fd, buf + fringe, &len); + if (rc < 0) { + if (errno != EPIPE) { close(fd); return -1; } + close(fd); + return 0; + } + buf[len - fringe] = '\0'; + rc = zet_links_in((char *)buf, id_to); + if (rc < 0) { close(fd); return -1; } + // in case a link is across the boundary between this buf and the next, + // keep some "fringe" of the end of this buf in the beginning of the + // next one + if (len > link_len) { + fringe = link_len; + memcpy(buf, buf + len - fringe, fringe); + } + } while (rc == 0); + close(fd); + return rc; +} + +static int zet_search_start(struct zet_search *zs, char *id) { + zs->dir = opendir(zet_dir); + if (zs->dir == NULL) return -1; + zs->id = id; + return 0; +} + +static int zet_search_next(struct zet_search *zs, const char **idp) { + int rc; + struct dirent *ent; + const char *id; + char *const dest_id = zs->id; + while (1) { + errno = 0; + ent = readdir(zs->dir); + if (ent == NULL) { + if (errno != 0) return -1; + id = NULL; + break; + } + id = ent->d_name; + if (id[0] == '.') continue; + if (strpbrk(id, "<>&\"~") != NULL) continue; + if (dest_id != NULL) { + rc = zet_links_to(id, zs->id); + if (rc < 0) return -1; + if (rc != 1) continue; + } + break; + }; + *idp = id; + return 0; +} + +static int zet_search_close(struct zet_search *sz) { + return closedir(sz->dir); +} + +static int dpi_serve_zet_index(int fd) { + int rc; + struct zet_search zs; + rc = zet_search_start(&zs, NULL); + if (rc < 0) return dpi_respond_err(fd, "Unable to list"); + rc = dpi_send_header(fd, "text/html"); + if (rc < 0) { warn("dpi_send_header"); close(fd); return 0; } + rc = dprintf(fd, + "" + "Notes" + "" + "" + "" + "
" TOPBAR_NAV_ALL "
" + "
    " + ); + const char *id; + while (1) { + rc = zet_search_next(&zs, &id); + if (rc < 0) { + rc = dprintf(fd, + "\nError: %s\n", + strerror(errno)); + if (rc < 0) warnx("dprintf"); + close(fd); + return 0; + } + if (id == NULL) break; + char title_buf[128]; + char *title = zet_get_title(id, title_buf, sizeof(title_buf)); + if (title == NULL) { + warn("zet_get_title"); + title = title_buf; + strncpy(title, id, sizeof(title)-1); + title[sizeof(title)-1] = '\0'; + return 0; + } + rc = dprintf(fd, "
  • ", id); + rc |= write_html(fd, title, strlen(title)); + rc |= write_buf(fd, "
  • "); + if (rc < 0) { warnx("dprintf/write_html/write_buf"); close(fd); return 0; } + } + rc = dprintf(fd, "
"); + if (rc < 0) { warn("dprintf"); close(fd); return 0; } + rc = zet_search_close(&zs); + if (rc < 0) warn("closedir"); + close(fd); + return 0; +} + +static int dpi_serve_not_found(int fd) { + int rc = dpi_send_header(fd, "text/html"); + if (rc < 0) { warn("dpi_send_header"); close(fd); return 0; } + write_buf(fd, "Not Found"); + close(fd); + return 0; +} + +static int dpi_serve_zet_new(int fd) { + int rc = dpi_send_header(fd, "text/html"); + if (rc < 0) { warn("dpi_send_header"); close(fd); return 0; } + dprintf(fd, + "" + "New Note" + "" + "" + "" + "
" TOPBAR_NAV_NEW "
" + "
" + "
" + "" + "
" + , server_url); + close(fd); + return 0; +} + +static void parse_req_uri(char *path, char **hashp, char **queryp) { + char *hash = *hashp = strchr(path, '#'); + if (hash != NULL) *hash++ = '\0'; + char *query = *queryp = strchr(path, '?'); + if (query != NULL) *query++ = '\0'; +} + +static int +md_rndr_link(struct buf *ob, const struct buf *link, const struct buf *title, const struct buf *content, void *opaque) +{ + struct html_renderopt *options = opaque; + + if (link != NULL && (options->flags & HTML_SAFELINK) != 0 && !sd_autolink_issafe(link->data, link->size)) + return 0; + + BUFPUTSL(ob, "size > sigil_size) { + if (!strncmp((char *)link->data, "§", sigil_size)) + houdini_escape_href(ob, link->data + sigil_size, + link->size - sigil_size); + else + houdini_escape_href(ob, link->data, link->size); + } + + if (title && title->size) { + BUFPUTSL(ob, "\" title=\""); + houdini_escape_html0(ob, title->data, title->size, 0); + } + + if (options->link_attributes) { + bufputc(ob, '\"'); + options->link_attributes(ob, link, opaque); + bufputc(ob, '>'); + } else { + BUFPUTSL(ob, "\">"); + } + + if (content && content->size) bufput(ob, content->data, content->size); + BUFPUTSL(ob, ""); + return 1; +} + +static void put_link_truncated(struct buf *ob, const struct buf *link) { + if (link->size < max_cols) { + return houdini_escape_html0(ob, link->data, link->size, 0); + } + houdini_escape_html0(ob, link->data, max_cols, 0); + BUFPUTSL(ob, "…"); +} + +static int +md_rndr_autolink(struct buf *ob, const struct buf *link, enum mkd_autolink type, void *opaque) +{ + struct html_renderopt *options = opaque; + + if (!link || !link->size) + return 0; + + if ((options->flags & HTML_SAFELINK) != 0 && + !sd_autolink_issafe(link->data, link->size) && + type != MKDA_EMAIL) + return 0; + + BUFPUTSL(ob, "data + sigil_size, link->size - sigil_size); + else + houdini_escape_href(ob, link->data, link->size); + + if (type == MKDA_ZET) { + char title_buf[128]; + char *title = zet_get_buf_title(link, title_buf, sizeof(title_buf)); + if (title != NULL) { + BUFPUTSL(ob, "\" title=\""); + houdini_escape_html0(ob, title, strlen(title), 0); + } + } + + if (options->link_attributes) { + bufputc(ob, '\"'); + options->link_attributes(ob, link, opaque); + bufputc(ob, '>'); + } else { + BUFPUTSL(ob, "\">"); + } + + /* + * Pretty printing: if we get an email address as + * an actual URI, e.g. `mailto:foo@bar.com`, we don't + * want to print the `mailto:` prefix + */ + if (bufprefix(link, "mailto:") == 0) { + houdini_escape_html0(ob, link->data + 7, link->size - 7, 0); + } else { + put_link_truncated(ob, link); + } + + BUFPUTSL(ob, ""); + + return 1; +} + +static int dpi_serve_zet(int fd, char *path) { + int rc; + char *hash, *query; + parse_req_uri(path, &hash, &query); + + if (!strcmp(path, "/")) return dpi_serve_zet_index(fd); + if (!strcmp(path, "/new")) return dpi_serve_zet_new(fd); + + char path_buf[_POSIX_PATH_MAX]; + char *id = path+1; + ssize_t sz = snprintf(path_buf, sizeof(path_buf), "%s/%s", zet_dir, id); + if (sz < 0 || (size_t)sz >= sizeof(path_buf)) return dpi_respond_err(fd, "read_file"); + + int note_fd = open(path_buf, O_RDONLY); + if (note_fd < 0 && errno == ENOENT) return dpi_serve_not_found(fd); + if (note_fd < 0) return dpi_respond_err(fd, "open"); + + int rows = count_lines(note_fd); + if (rows < 0) return dpi_respond_err(fd, "count_lines"); + static const int max_rows = 57, min_rows = 8; + if (rows > max_rows) rows = max_rows; + else if (rows < min_rows) rows = min_rows; + rc = lseek(note_fd, 0, SEEK_SET); + if (rc < 0) return dpi_respond_err(fd, "lseek"); + + rc = dpi_send_header(fd, "text/html"); + rc |= dprintf(fd, + "" + "§%s" + "" + "" + "
" TOPBAR_NAV " §%s
" + "" + "" + "" + ""); + if (rc < 0) warn("dprintf"); + + rc = dprintf(fd, ""); + if (rc < 0) warn("dprintf"); + (void)zet_search_close(&zs); + + rc = dprintf(fd, "
" + "
" + "" + "
" + ); + if (rc < 0) { warn("dpi_send_header"); close(fd); return 0; } + rc = lseek(note_fd, 0, SEEK_SET); + if (rc < 0) { + rc = dprintf(fd, "\nError: %s", strerror(errno)); + if (rc < 0) warnx("dprintf"); + close(fd); + } + char *text = read_full(note_fd); + if (text == NULL) { + rc = dprintf(fd, "\nError: %s", strerror(errno)); + if (rc < 0) warnx("dprintf"); + close(fd); + } + + struct sd_callbacks callbacks; + struct html_renderopt options; + struct sd_markdown *markdown; + struct buf *ob = bufnew(128); + sdhtml_renderer(&callbacks, &options, HTML_ESCAPE); + callbacks.link = md_rndr_link; + callbacks.autolink = md_rndr_autolink; + static const unsigned int extensions = + MKDEXT_NO_INTRA_EMPHASIS | + MKDEXT_TABLES | + MKDEXT_FENCED_CODE | + MKDEXT_AUTOLINK | + MKDEXT_STRIKETHROUGH | + MKDEXT_SPACE_HEADERS | + MKDEXT_LAX_SPACING; + markdown = sd_markdown_new(extensions, 16, &callbacks, &options); + sd_markdown_render(ob, (unsigned char *)text, strlen(text), markdown); + free(text); + sd_markdown_free(markdown); + rc = write_all(fd, ob->data, ob->size); + if (rc < 0) warn("write_all"); + bufrelease(ob); + rc = dprintf(fd, "
"); + if (rc < 0) warn("dprintf"); + struct zet_search zs; + bool first = true; + rc = zet_search_start(&zs, id); + if (rc < 0) warn("zet_search_start"); + do { + const char *result_id; + rc = zet_search_next(&zs, &result_id); + if (rc < 0) warn("zet_search_next"); + if (result_id == NULL) break; + if (first) { + first = false; + rc = dprintf(fd, "Backlinks:
    "); + if (rc < 0) warn("dprintf"); + } + char title_buf[128]; + char *result_title = zet_get_title(result_id, title_buf, sizeof(title_buf)); + if (result_title == NULL) { + warn("zet_get_title"); + result_title = title_buf; + strncpy(result_title, result_id, sizeof(result_title)-1); + result_title[sizeof(result_title)-1] = '\0'; + return 0; + } + rc = dprintf(fd, "
  • ", result_id); + rc |= write_html(fd, result_title, strlen(result_title)); + rc |= write_buf(fd, "
  • "); + } while (1); + if (!first) (void)dprintf(fd, "
"); + rc = dprintf(fd, "
"); + if (rc < 0) warn("dprintf"); + + close(fd); + return 0; +} + +static int handle_dpi_client(int fd) { + int rc; + char url[2048]; + rc = dpi_check_auth(fd); + if (rc < 0) { + warn("dpi auth"); + close(fd); + return 0; + } + rc = dpi_read_request(fd, url, sizeof(url)); + if (rc < 0) { + if (errno == ESHUTDOWN) return -1; + warn("dpi request"); + dpi_respond_err(fd, "Unable to read request"); + return 0; + } + if (!strncmp(url, "dpi:/zet/", 9)) { + return dpi_serve_zet(fd, url + 8); + } + return dpi_serve_not_found(fd); +} + +static char *next_line(char *str) { + char *nextline = strchr(str, '\n'); + if (nextline != NULL) { + if (nextline[-1] == '\r') nextline[-1] = '\0'; + else *nextline = '\0'; + nextline++; + } + return nextline; +} + +static int http_serve_index(struct http_request *req) { + write_buf(req->fd, "HTTP/1.0 200 OK\r\nConnection: close\r\n\r\n"); + close(req->fd); + return 0; +} + +static int save_part(struct http_request *req, int note_fd) { + int rc = write_all(note_fd, (unsigned char *)req->data, req->len); + rc |= close(note_fd); + free(req->full_data); + return rc; +} + +static int parse_multipart(struct http_request *req) { + size_t boundary_len = req->multipart_boundary != NULL + ? strlen(req->multipart_boundary) : 0; + if (boundary_len == 0) return -1; + ssize_t len = req->content_length; + if (len < 0) return -1; + if (req->len < (size_t)len) { + req->full_data = malloc(len+1); + memcpy(req->full_data, req->data, req->len); + char *rest = req->full_data + req->len; + int rc = read_all(req->fd, (unsigned char *)rest, len - req->len); + if (rc < 0) return -1; + req->data = req->full_data; + req->len = len; + } + req->data[req->len] = '\0'; + char *boundary_start = NULL; + while (req->len > 0) { + boundary_start = strstr(req->data, req->multipart_boundary); + if (boundary_start == NULL) return -1; + boundary_start += boundary_len; + char *line = boundary_start; + char *cdisp = NULL; + bool is_text = false; + if (*line == '\r') line++; + if (*line == '\n') line++; + char *nextline; + while (line != NULL) { + nextline = next_line(line); + if (!line[0]) break; + char *name = line; + char *value = strchr(line, ':'); + if (value != NULL) { + *value++ = '\0'; + while (*value == ' ') value++; + } + if (!strncmp(name, "Content-Disposition", 3)) cdisp = value; + line = nextline; + } + if (cdisp != NULL && !strcmp(cdisp, "form-data; name=\"text\"")) { + is_text = true; + } + req->len -= nextline - req->data; + req->data = nextline; + + char *end = strstr(nextline, req->multipart_boundary); + if (end == NULL || strncmp(end + boundary_len, "--", 2)) return -1; + if (end[-1] == '\n') end--; + if (end[-1] == '\r') end--; + *end = '\0'; + req->len = end - nextline; + if (is_text) break; + } + return 0; +} + +static int http_serve_new(struct http_request *req) { + int rc; + char note_path[_POSIX_PATH_MAX]; + char id[64]; + + rc = parse_multipart(req); + if (rc < 0) { + write_buf(req->fd, "HTTP/1.0 400 Bad Request\r\n" + "Content-Type: text/plain\r\n" + "Connection: close\r\n\r\n" + "Unable to parse form submission"); + close(req->fd); + return 0; + } + + (void)mkdir(zet_dir, 0700); + + srandom(time(NULL) ^ getpid()); + (void)snprintf(id, sizeof(id), "%08lx%08lx", random(), random()); + (void)snprintf(note_path, sizeof(note_path), "%s/%s", zet_dir, id); + int note_fd = open(note_path, O_CREAT|O_WRONLY|O_TRUNC, 0640); + if (note_fd < 0) { + dprintf(req->fd, "HTTP/1.0 500 Internal Server Error\r\n" + "Content-Type: text/plain\r\n" + "Connection: close\r\n\r\n" + "Unable to open file: %s\n", strerror(errno)); + close(req->fd); + return 0; + } + + rc = save_part(req, note_fd); + if (rc < 0) { + dprintf(req->fd, "HTTP/1.0 200 OK\r\n" + "Content-Type: text/plain\r\n" + "Connection: close\r\n\r\n" + "Error saving: %s", strerror(errno)); + close(req->fd); + return 0; + } + + dprintf(req->fd, "HTTP/1.0 302 Found\r\n" + "Content-Type: text/html\r\n" + "Location: dpi:/zet/%s\r\n" + "Connection: close\r\n\r\n" + "" + "Created: §%s" + "" + "" + "Created: §%s" + "" + , id, id, id, id); + close(req->fd); + return 0; +} + +static int http_serve_not_found(struct http_request *req) { + dprintf(req->fd, "HTTP/1.0 200 OK\r\n" + "Connection: close\r\n\r\n" + "Not found\n"); + close(req->fd); + return 0; +} + +static int http_serve_zet(struct http_request *req) { + int rc; + char note_path[_POSIX_PATH_MAX]; + char note_path_backup[_POSIX_PATH_MAX]; + char *id = req->path + 1; + + rc = parse_multipart(req); + if (rc < 0) { + write_buf(req->fd, "HTTP/1.0 400 Bad Request\r\n" + "Content-Type: text/plain\r\n" + "Connection: close\r\n\r\n" + "Unable to parse form submission"); + close(req->fd); + return 0; + } + + (void)snprintf(note_path, sizeof(note_path), "%s/%s", zet_dir, id); + (void)snprintf(note_path_backup, sizeof(note_path_backup), "%s/%s~", zet_dir, id); + + rc = rename(note_path, note_path_backup); + if (rc < 0 && errno != ENOENT) warn("rename"); + + int note_fd = open(note_path, O_CREAT|O_WRONLY|O_TRUNC, 0640); + if (note_fd < 0) { + if (errno == ENOENT) return http_serve_not_found(req); + dprintf(req->fd, "HTTP/1.0 500 Internal Server Error\r\n" + "Content-Type: text/plain\r\n" + "Connection: close\r\n\r\n" + "Unable to open file: %s\n", strerror(errno)); + close(req->fd); + return 0; + } + + rc = save_part(req, note_fd); + if (rc < 0) { + dprintf(req->fd, "HTTP/1.0 200 OK\r\n" + "Content-Type: text/plain\r\n" + "Connection: close\r\n\r\n" + "Error saving: %s", strerror(errno)); + close(req->fd); + return 0; + } + + dprintf(req->fd, "HTTP/1.0 302 Found\r\n" + "Content-Type: text/html\r\n" + "Location: dpi:/zet/%s\r\n" + "Connection: close\r\n\r\n" + "" + "Saved: §%s" + "" + "" + "Saved: §%s" + "" + , id, id, id, id); + close(req->fd); + return 0; +} + +static int handle_http_client(int fd, int firstchar) { + int rc; + struct http_request req; + char buf[2048]; + buf[0] = firstchar; + size_t len = sizeof(buf)-1; + rc = read_some(fd, (unsigned char *)buf+1, &len); + buf[len+1] = '\0'; + len++; + if (rc < 0) { close(fd); return 0; } + + char *nextline = next_line(buf); + req.method = buf; + req.path = strchr(buf, ' '); + if (req.path == NULL) { close(fd); return 0; } + *req.path++ = '\0'; + req.http_version = strchr(req.path, ' '); + if (req.http_version != NULL) *req.http_version++ = '\0'; + + req.referer = NULL; + req.host = NULL; + req.content_length = -1; + req.content_type = NULL; + req.multipart_boundary = NULL; + + char *line = nextline; + while (line != NULL) { + nextline = next_line(line); + if (!line[0]) break; + char *name = line; + char *value = strchr(line, ':'); + if (value != NULL) { + *value++ = '\0'; + while (*value == ' ') value++; + } + if (!strncmp(name, "Host", 3)) req.host = value; + else if (!strncmp(name, "Referer", 7)) req.referer = value; + else if (!strncmp(name, "Content-Length", 14)) req.content_length = atoi(value); + else if (!strncmp(name, "Content-Type", 14)) req.content_type = value; + // else fprintf(stderr, "%s = %s\n", name, value); + line = nextline; + } + + if (req.content_type != NULL + && !strncmp(req.content_type, "multipart/", 10)) { + char *subtype = req.content_type + 10; + char *boundary = strstr(subtype, "; boundary="); + if (boundary != NULL) { + *boundary = '\0'; + boundary += 11; + if (boundary[0] == '"') { + boundary++; + char *end = strchr(boundary, '"'); + if (end != NULL) *end = '\0'; + } + *--boundary = '-'; + *--boundary = '-'; + req.multipart_boundary = boundary; + } + } + + if (req.referer == NULL || strncmp(req.referer, server_url, strlen(server_url))) { + dprintf(fd, "HTTP/1.0 403 Forbidden\r\n" + "Connection: close\r\n\r\n" + "Invalid Referer\n"); + close(fd); + return 0; + } + + if (req.host != NULL && strcmp(req.host, server_hostname)) { + dprintf(fd, "HTTP/1.0 403 Forbidden\r\n" + "Connection: close\r\n\r\n" + "Invalid Host\n"); + close(fd); + return 0; + } + + ptrdiff_t offset = nextline - buf; + req.data = nextline; + req.full_data = NULL; + req.len = len - offset; + req.fd = fd; + + parse_req_uri(req.path, &req.hash, &req.query); + + if (!strcmp(req.path, "/")) return http_serve_index(&req); + if (!strcmp(req.path, "/new")) return http_serve_new(&req); + return http_serve_zet(&req); +} + +static int handle_client(int server_fd) { + int fd; + do { + fd = accept(server_fd, NULL, NULL); + if (fd < 0 && errno != ENETDOWN && errno != EPROTO + && errno != ENOPROTOOPT && errno != EHOSTDOWN + && errno != ENONET && errno != EHOSTUNREACH + && errno != EOPNOTSUPP && errno != ENETUNREACH + ) return -1; + } while (fd < 0); + int firstchar = read_char(fd); + if (firstchar < 0) { + // ignore errno + close(fd); + return 0; + } + if (firstchar == '<') return handle_dpi_client(fd); + return handle_http_client(fd, firstchar); +} + +void get_server_address() { + struct sockaddr_storage addr; + struct sockaddr *addrp = (struct sockaddr *)&addr; + socklen_t addr_len = sizeof(addr); + char host_buf[128]; + const char *host; + unsigned short port; + int rc = getsockname(STDIN_FILENO, addrp, &addr_len); + if (rc < 0) err(1, "getsockname"); + if (addr.ss_family == AF_INET) { + struct sockaddr_in *addr_in = (struct sockaddr_in *)&addr; + port = ntohs(addr_in->sin_port); + host = inet_ntop(AF_INET, &addr_in->sin_addr, host_buf, sizeof(host_buf)); + } else if (addr.ss_family == AF_INET6) { + struct sockaddr_in6 *addr_in6 = (struct sockaddr_in6 *)&addr; + port = ntohs(addr_in6->sin6_port); + host = inet_ntop(AF_INET6, &addr_in6->sin6_addr, host_buf, sizeof(host_buf)); + } else { + errx(1, "Unknown server address family: %d", addr.ss_family); + } + int wrote = snprintf(server_hostname, sizeof(server_hostname), "%s:%hu", host, port); + if (wrote <= 0 || wrote >= (int)sizeof(server_hostname)) { + errx(1, "Unable to write hostname"); + } + wrote = snprintf(server_url, sizeof(server_url), "http://%s/", server_hostname); + if (wrote <= 0 || wrote >= (int)sizeof(server_url)) { + errx(1, "Unable to write local URL"); + } +} + +int main(int argc, char *argv[]) { + (void)argc; + (void)argv; + + warnx("started"); + + const char *home = getenv("HOME"); + int len = snprintf(zet_dir, sizeof(zet_dir), "%s/.zet", home); + if (len < 0 || len >= (int)sizeof(zet_dir)) { + err(1, "unable to build directory name"); + } + + // Since dpi requests don't support a request body, we POST via HTTP + // to our dpi server socket which is already listing on a local TCP port. + get_server_address(); + + // handle connections one at a time + while (handle_client(STDIN_FILENO) == 0); + + warnx("exiting"); +}