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Rename guestfs_safe_malloc et al to guestfs___safe_malloc etc. To use the private functions, code now has to define -DGUESTFS_PRIVATE_FUNCTIONS=1. This will make it easier for us in future to work out which programs are using these functions and to minimize both the number of programs and the functions they are calling. Note that the Perl, Python, OCaml, Ruby and Java bindings use guestfs_safe_* calls. None of the other bindings do. This is a bug (in the bindings using those functions): these functions will call the out of memory callback on failure. This function defaults to abort(), and since this happens from a language binding, there is no way to change this default.
This program generates a large amount of code and documentation for all the daemon actions. To add a new action there are only two files you need to change, 'actions.ml' to describe the interface, and daemon/<somefile>.c to write the implementation. After editing these files, build it (make -C generator) to regenerate all the output files. 'make' will rerun this automatically when necessary. IMPORTANT: This program should NOT print any warnings at compile time or run time. If it prints warnings, you should treat them as errors. OCaml tips: (1) In emacs, install tuareg-mode to display and format OCaml code correctly. 'vim' comes with a good OCaml editing mode by default. (2) Read the resources at http://ocaml-tutorial.org/ (3) A module called 'Foo' is defined in one or two files called 'foo.mli' and 'foo.ml' (NB: lowercase first letter). The *.mli file, if present, defines the public interface for the module. The *.ml file is the implementation. If the *.mli file is missing then everything is exported. Some notable files in this directory: actions.ml The libguestfs API. structs.ml Structures returned by the API. c.ml Generate C API. <lang>.ml Generate bindings for <lang>. main.ml The main generator program. Note about long descriptions: When referring to another action, use the format C<guestfs_other> (ie. the full name of the C function). This will be replaced as appropriate in other language bindings. Apart from that, long descriptions are just perldoc paragraphs. Note about extending functions: In general you cannot change the name, number of required arguments or type of required arguments of a function, since this would break backwards compatibility. You may add another optional argument, *if* the function has >= 1 optional arguments already. Add it at the end of the list. You may add optional arguments to a function that doesn't have any. However you *must* set the once_had_no_optargs flag to true, so that the relevant backwards compatibility bindings can be added.