X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=HACKING;h=df28b7affabb3193e6bb12165996ae5dbfe4a791;hp=6ca33be31c7d1692baa2e931f62caecfae3abd90;hb=4d900cdac8258daa2e99c6ceb2a4985154e94150;hpb=bdf7a27a790ff26664f91d95239ec33c5467bfeb diff --git a/HACKING b/HACKING index 6ca33be..df28b7a 100644 --- a/HACKING +++ b/HACKING @@ -7,8 +7,8 @@ Adding a new action All action functions are generated automatically, so there are only two files you need to edit: -(1) src/generator.ml: Add your new action, parameters, description, -etc. to the big list called 'functions' at the top of this file. +(1) generator/generator_actions.ml: Add your new action, parameters, +description, etc. to the big list at the top of this file. (2) Edit/create a C file in daemon/ subdirectory which implements your 'do_action' function. Take a look at one of the numerous examples @@ -24,75 +24,137 @@ Please make sure that the code compiles without warnings. Please test any changes. +Useful targets: + make syntax-check Checks the syntax of the C code. + make check Runs the test suite. + +Enable warnings, and fix any you find: + ./configure --enable-gcc-warnings + +Code indentation +---------------------------------------------------------------------- +Our C source code generally adheres to some basic code-formatting +conventions. The existing code base is not totally consistent on this +front, but we do prefer that contributed code be formatted similarly. +In short, use spaces-not-TABs for indentation, use 2 spaces for each +indentation level, and other than that, follow the K&R style. + +If you use Emacs, add the following to one of one of your start-up files +(e.g., ~/.emacs), to help ensure that you get indentation right: + + ;;; In libguestfs, indent with spaces everywhere (not TABs). + ;;; Exceptions: Makefile and ChangeLog modes. + (add-hook 'find-file-hook + '(lambda () (if (and buffer-file-name + (string-match "/libguestfs\\>" (buffer-file-name)) + (not (string-equal mode-name "Change Log")) + (not (string-equal mode-name "Makefile"))) + (setq indent-tabs-mode nil)))) + + ;;; When editing C sources in libguestfs, use this style. + (defun libguestfs-c-mode () + "C mode with adjusted defaults for use with libguestfs." + (interactive) + (c-set-style "K&R") + (setq c-indent-level 2) + (setq c-basic-offset 2)) + (add-hook 'c-mode-hook + '(lambda () (if (string-match "/libguestfs\\>" (buffer-file-name)) + (libguestfs-c-mode)))) + Directories ---------------------------------------------------------------------- appliance/ - The qemu appliance, build scripts and so on. - -cat/ - The virt-cat tool. + The qemu appliance, build scripts and so on. capitests/ - Automated tests of the C API. + Automated tests of the C API. contrib/ - Outside contributions, experimental parts. + Outside contributions, experimental parts. -daemon/ - The daemon that runs inside the guest and carries out actions. +csharp/ + Experimental C# bindings. -df/ - The virt-df tool. +daemon/ + The daemon that runs inside the guest and carries out actions. examples/ - The examples. + The examples. fish/ - Guestfish (the command-line program / shell) + Guestfish (the command-line program / shell) + +fuse/ + FUSE (userspace filesystem) built on top of libguestfs. + +generator/ + The crucially important generator, used to automatically + generate large amounts of boilerplate C code for things like + RPC and bindings. haskell/ - Haskell bindings. + Haskell bindings. + +hivex/ [removed in 1.0.85] + This used to contain the hivex library for reading and + writing Windows Registry binary hive files. This is now + available as a separate upstream project. images/ - Some guest images to test against. These are gzipped to save - space. You have to unzip them before use. + Some guest images to test against. These are gzipped to save + space. You have to unzip them before use. - Also contains some files used by the test suite. + Also contains some files used by the test suite. inspector/ - Virtual machine image inspector (virt-inspector). + Virtual machine image inspector (virt-inspector). java/ - Java bindings. + Java bindings. m4/ - M4 macros used by autoconf. + M4 macros used by autoconf. ocaml/ - OCaml bindings. + OCaml bindings. + +php/ + PHP bindings. po/ - Translations. + Translations of simple gettext strings. For translations of + longer documents, see po-docs/. + +po-docs/ + The build infrastructure and PO files for translations of + manpages and POD files. Eventually this will be combined + with the po/ directory, but that is rather complicated. perl/ - Perl bindings. + Perl bindings. python/ - Python bindings. + Python bindings. regressions/ - Regression tests. + Regression tests. ruby/ - Ruby bindings. + Ruby bindings. + +tools/ + Command line tools like virt-cat, virt-df, virt-edit and more. + In versions <= 1.0.73 these were all in separate directories + like cat/, df/, edit/, but since then we moved them all into + one directory to simplify builds. src/ - Source code to the C library. - Also contains the crucial generator program. + Source code to the C library. -v2v/ - Xen to KVM (V2V) conversion tool. +test-tool/ + Interactive qemu/kernel test tool. Debugging ---------------------------------------------------------------------- @@ -123,3 +185,25 @@ into the appliance. Debugging messages are never translated, since they are intended for the programmers. + +Extended printf +---------------------------------------------------------------------- + +In the daemon code we have created custom printf formatters %Q and %R, +which are used to do shell quoting. + +%Q => Simple shell quoted string. Any spaces or other shell characters + are escaped for you. + +%R => Same as %Q except the string is treated as a path which is prefixed + by the sysroot. + +eg. + +asprintf (&cmd, "cat %R", path); +==> "cat /sysroot/some\ path\ with\ spaces" + +Note: Do NOT use these when you are passing parameters to the +command{,r,v,rv}() functions. These parameters do NOT need to be +quoted because they are not passed via the shell (instead, straight to +exec). You probably want to use the sysroot_path() function however.