zproject_class_api.gsl

#   Process class API files in api/*.api
#
#   This is a code generator built using the iMatix GSL code generation
#   language. See https://github.com/imatix/gsl for details.
#
#   Copyright (c) the Contributors as noted in the AUTHORS file.
#   This file is part of zproject.
#
#   This Source Code Form is subject to the terms of the Mozilla Public
#   License, v. 2.0. If a copy of the MPL was not distributed with this
#   file, You can obtain one at http://mozilla.org/MPL/2.0/.

# Resolve filename for each class API (undefined if the file is not found)
for project.class
    class.private ?= "0"
    if defined (class.api)
        if !file.exists (class.api)
            echo "Could not read API file '$(class.api)' for '$(class.name)'"
            class.api = # undefined
        endif
    else
        if file.exists ("api/$(class.name:c).api")
            class.api = "api/$(class.name:c).api"
        elsif file.exists ("api/$(class.name:c).xml")
            class.api = "api/$(class.name:c).xml"
        endif
    endif
endfor

# Replace each class item with the class model from its API file (if any)
for project.class where defined (class.api)
    new_class = XML.load_file (class.api)?
    if !defined (new_class)
        echo "Error loading api file: $(class.api): $(xml.error?)"
        class.api = # undefined
    else
        new_class.api = class.api
        new_class.api_dir = directory.resolve ('api/')
        new_class.private = class.private
        new_class.scope = class.scope
        new_class.state = class.state? new_class.state?
        new_class.selftest ?= 1
        move new_class after class
        delete class
    endif
endfor

#
# Set the API state and draft attribute of an element
#
function set_state (element, default)
    my.element.state ?= my.default
    if my.element.state = "stable" \
    |  my.element.state = "legacy" \
    |  my.element.private ?= 1
        my.element.draft = 0
    elsif my.element.state = "draft"
        my.element.draft = 1
    else
        abort "E: $(name (element)).state must be draft/stable/legacy (is '$(my.element.state)')"
    endif
endfunction

# Resolve missing or implicit details in the given container.
#
# Here, "container" refers to an <argument/> or <return/> in the model XML.
# In other words, a container fully describes any value / variable reference
# that can be passed to or returned from a method.
#
function resolve_c_container (container)
    # Resolve semantic attributes.
    #
    # After this function, these should all be fully resolved to a value.
    # Some changes may occur later in this function during type resolution.
    #
    my.container.name ?= "_"
    my.container.type ?= "nothing"
    my.container.by_reference ?= 0
    my.container.callback ?= 0
    my.container.fresh ?= 0
    my.container.variadic ?= 0
    my.container.optional ?= 0

    # Resolve language-specific attributes for the C language.
    #
    # It's important to do this here because languages that bind
    # directly to the C implementation will need C-specific information
    # to bind correctly when they run later.
    #
    my.container.c_name ?= "$(my.container.name:c)"
    if defined (my.container.c_type)
        return
    endif

    my.type = my.container.type
    my.size = my.container.size? 1
    my.c_type = ""
    my.stars = ""

    # Resolve the `c_type` for this `type`, finish tweaking semantic attributes.
    #
    if my.type = ""
        my.c_type = "void"
    elsif my.type = "nothing"
        my.c_type = "void"
    elsif my.type = "anything" | my.type = "sockish"
        my.c_type = "void"
        my.stars = "*"
    elsif my.type = "byte"
        my.c_type = "byte"
    elsif my.type = "char"
        my.c_type = "char"
    elsif my.type = "integer"
        my.c_type = "int"
    elsif my.type = "size"
        my.c_type = "size_t"
    elsif my.type = "real"
        my.c_type = "float"
    elsif my.type = "number"
        if my.size = 1
            my.c_type = "uint8_t"
        elsif my.size = 2
            my.c_type = "uint16_t"
        elsif my.size = 4
            my.c_type = "uint32_t"
        elsif my.size = 8
            my.c_type = "uint64_t"
        endif
    elsif my.type = "boolean"
        my.c_type = "bool"
    elsif my.type = "file_size"
        my.c_type = "off_t"
    elsif my.type = "time"
        my.c_type = "time_t"
    elsif my.type = "msecs"
        my.c_type = "int64_t"
    elsif my.type = "FILE"
        my.c_type = "FILE"
        my.stars = "*"
    elsif my.type = "va_list"
        my.c_type = "va_list"
    elsif my.type = "socket"
        my.c_type = "SOCKET"
    elsif my.type = "zmq_pollitem"
        my.c_type = "zmq_pollitem_t"
        my.stars = "*"
    elsif my.type = "string"
        my.c_type = "char"
        my.stars = "*"
        if my.container.fresh = 1 | my.container.by_reference = 1
            my.container.mutable ?= 1
        else
            my.container.mutable ?= 0
        endif
    elsif my.type = "format"
        my.c_type = "char"
        my.stars = "*"
        my.container.mutable ?= 0
        my.container.variadic = 1
    elsif my.type = "buffer"
        my.c_type = "byte"
        my.stars = "*"
        if my.container.fresh = 1 | my.container.by_reference = 1
            my.container.mutable ?= 1
        else
            my.container.mutable ?= 0
        endif
    elsif my.container.callback
        my.c_type = "$(my.type:c)"
    else
        #   Map unknown type XYZ to "XYZ_t *" and resolve later
        my.container.foreign = 1
        my.c_type = "$(my.type:c)_t"
        my.stars = "*"
    endif

    if my.container.by_reference
        my.stars += "*"
    endif

    # This attribute is resolved late because it may be influenced during type resolution
    my.container.mutable ?= 1
    if !my.container.mutable
        my.c_type = "const " + my.c_type
    endif

    if string.length (my.stars)
        my.c_type += " " + my.stars
    endif

    my.container.c_type = my.c_type
endfunction


# Resolve missing or implicit details in a C method model.
#
# Here, "actor" refers to a <actor/> entity in the model XML.
#
function resolve_c_actor (actor, default_description)
    # Resolve semantic attributes
    my.actor.description ?= "$(string.trim (my.actor.?my.default_description):left)"
endfunction


# Resolve missing or implicit details in a C method model.
#
# Here, "method" refers to a <method/> entity in the model XML.
#
# All inner containers (arguments and returns) will be fully resolved,
# as well as any semantic or C-specific attributes of the method itself.
#
function resolve_c_method (method, default_description)
    # Resolve semantic attributes
    my.method.name ?= "_"
    my.method.description ?= "$(string.trim (my.method.?my.default_description):left)"
    my.method.singleton ?= 0
    my.method.is_constructor ?= 0
    my.method.is_destructor ?= 0
    my.method.polymorphic ?= 0

    # Resolve language-specific attributes for the C language.
    my.method.c_name ?= "$(my.method.name:c)"

    # Add an implicit return container if none exists.
    if !count (my.method.return)
        new return to my.method
        endnew
    endif

    # Resolve each argument container in the method.
    for my.method.argument as container
        resolve_c_container (container)
        if container.variadic
            #   Create a new argument to represent the variadic arguments
            #   ------------------------------------------------------------
            #   PH 2015/11/29: variadic means two different things depending
            #   on how far we got through processing, which is kind of nasty.
            #   ------------------------------------------------------------
            container.variadic = 0
            new argument to my.method
                argument.variadic = 1
                argument.va_start = container.name
                #  Won't be included in current loop, so resolve now
                resolve_c_container (argument)
            endnew
        endif
    endfor

    # Resolve each return container in the method.
    for my.method.return as container
        resolve_c_container (container)
        if container.type = "format"
            abort "method cannot return a 'format'"
        endif
    endfor
endfunction

# Resolve C constant
function resolve_c_constant (constant, default_state)
    if defined (my.constant.type) & (my.constant.type = 'string')
        my.constant.value = '"' + my.constant.value + '"'
    endif
    my.constant.description ?= "$(string.trim (my.constant.?""):left)"
    resolve_c_container (my.constant)
    set_state (my.constant, my.default_state)
endfunction

#   Resolve missing or implicit details in a C class model
#
#   Here, "class" refers to a <class/> entity in the model XML.
#
#   All inner methods will be fully resolved, as well as any
#   semantic or C-specific attributes of the method itself.
#
function resolve_c_class (class)
    my.class.c_name ?= "$(my.class.name:c)"
    my.class.description ?= "$(string.trim (my.class.?""):left)"

    set_state (my.class, "draft")

    # Includes of XML files
    for my.class.include
        if !defined (include.filename)
            abort "E: required attribute 'filename' not defined"
        endif
        my.include_file = my.class.load_file (my.class.api_dir + filename)?
        if defined (my.include_file)
            move my.include_file after include
        else
            abort "E: <include> failed: $(xml.error?)"
        endif
    endfor

    # All classes must have a test method
    if !count (my.class.method, method.name = "test")
        new method to my.class
            method.name = "test"
            method.singleton = 1
            method.description = "Self test of this class."
            new argument to method
                argument.name = "verbose"
                argument.type = "boolean"
            endnew
        endnew
    endif

    # Resolve details of each method
    for my.class.callback_type as method
        resolve_c_method (method, "")
        set_state (method, my.class.state)
    endfor

    # Resolve details of an actor
    for my.class.actor
        actor.name ?= "$(class.name:c)"
        resolve_c_actor (actor, "")
    endfor

    for my.class.method
        resolve_c_method (method, "")
        set_state (method, my.class.state)
        # Test if a variadic function has a sibling that accepts a va_list.
        # By convention these sibling methods prepend a 'v' to the method name.
        # This information might be used by the various language bindings.
        method.has_va_list_sibling = 0
        if count (method.argument, argument.variadic ?= "1")
            for my.class.method as m
                if m.name = "v" + method.name \
                &  count (m.argument, argument.type = "va_list")
                    method.has_va_list_sibling = 1
                endif
            endfor
        endif
    endfor

    for my.class.constructor as method
        method.name ?= "new"
        method.singleton = 1
        method.is_constructor = 1
        method.has_va_list_sibling = 0
        # Add a new return value to the first slot - the created object
        new return to method as ret
            ret.type = my.class.c_name
            # constructors always return a fresh value
            ret.fresh = 1
            move ret before method->return # Move to first slot
        endnew
        resolve_c_method (method, "Create a new $(my.class.c_name).")
        set_state (method, my.class.state)
    endfor

    for my.class.destructor as method
        method.name ?= "destroy"
        method.singleton = 1
        method.is_destructor = 1
        method.has_va_list_sibling = 0
        # Add a new argument to the first slot - the object to be destroyed
        new argument to method as arg
            arg.type = my.class.c_name
            arg.name = "self_p"
            arg.by_reference = 1
            arg.destructor_self = 1
            move arg before method->argument # Move to first slot
        endnew
        resolve_c_method (method, "Destroy the $(my.class.c_name).")
        set_state (method, my.class.state)
    endfor

    # Resolve details of each constant
    for my.class.constant
        resolve_c_constant (constant, my.class.state)
    endfor
endfunction


#   Resolve all dependent data types for one container and load their API file
#   if it exists.
#
function resolve_container_dependencies (class_name, container)
    if my.container.foreign ?= 1 \
    & count (project.class, class.c_name = my.container.type) = 0 \
    & count (project->dependencies.class, class.c_name = my.container.type) = 0
        resolved = 0
        # Search the installation directory for the dependency
        install_dir = directory.open ("/usr/local/share/zproject")?
        if defined (install_dir)
            for install_dir.directory
                api_file = directory.path + directory.name + "/"  + "$(my.container.type:c).xml"
                if resolved = 0 & file.exists (api_file)
                    dependency = XML.load_file (api_file)
                    dependency.api_dir = directory.path + directory.name + "/"
                    dependency.resolved = 0
                    dependency.project = directory.name
                    resolve_c_class (dependency)
                    move dependency to project->dependencies
                    resolved = 1
                endif
                api_file = directory.path + directory.name + "/"  + "$(my.container.type:c).api"
                if resolved = 0 & file.exists (api_file)
                    dependency = XML.load_file (api_file)
                    dependency.api_dir = directory.path + directory.name + "/"
                    dependency.resolved = 0
                    dependency.project = directory.name
                    resolve_c_class (dependency)
                    move dependency to project->dependencies
                    resolved = 1
                endif
            endfor
        endif
        if !resolved
            # Search the workspace directory for the dependency
            workspace_dir = directory.open ("..")?
            if defined (workspace_dir)
                for workspace_dir.directory
                    api_file = directory.path + directory.name + "/api/"  + "$(my.container.type:c).xml"
                    if resolved = 0 & file.exists (api_file)
                        dependency = XML.load_file (api_file)
                        dependency.api_dir = directory.path + directory.name + "/api/"
                        dependency.resolved = 0
                        dependency.project = directory.name
                        resolve_c_class (dependency)
                        move dependency to project->dependencies
                        resolved = 1
                    endif
                    api_file = directory.path + directory.name + "/api/"  + "$(my.container.type:c).api"
                    if resolved = 0 & file.exists (api_file)
                        dependency = XML.load_file (api_file)
                        dependency.api_dir = directory.path + directory.name + "/api/"
                        dependency.resolved = 0
                        dependency.project = directory.name
                        resolve_c_class (dependency)
                        move dependency to project->dependencies
                        resolved = 1
                    endif
                endfor
            endif
        endif
        if !resolved
            echo "W: in $(class.name): '" + my.container.type +"' does not resolve to a class"
        endif
    endif
endfunction

# Resolve all dependent data types from foreign zproject projects.
#
function resolve_class_dependencies (class)
    # Create dependencies tag if it doesn't exists
    if count (project.dependencies) = 0
        dependencies = XML.new ("dependencies")
        move dependencies to project
    endif
    # Resolve argument and return containers
    for my.class.method
        for method.argument
            resolve_container_dependencies (my.class.name, argument)
        endfor
        for method.return
            resolve_container_dependencies (my.class.name, return)
        endfor
    endfor
endfunction

##
# The following functions are entirely C-specific code generation helpers.
# They contain no useful information for higher-level language bindings.

function _c_method_arglist (method)
    # this requires the tmp_args to be set up
    my.out = "("
    for my.method.tmp_arg as argument
        if argument.variadic
            my.out += "..."
        else
            my.out += argument.c_type?""
            if !regexp.match ("\\*$", argument.c_type?"")
                my.out += " "
            endif
            my.out += (argument.c_name?"") + (last() ?? '' ? ', ')
        endif
    endfor
    if count(my.method.tmp_arg) = 0
        my.out += "void"
    endif
    my.out += ")"
    return my.out
endfunction

function c_method_signature (method)
    # this will set method.format_index to the index of
    # the format argument, if any
    if !my.method.singleton
        new tmp_arg to method as arg
            arg.name = 'self'
            arg.c_name = 'self'
            arg.type = '__self__'
            arg.variadic = 0
            if my.method.polymorphic?0
                arg.c_type = 'void *'
            else
                arg.c_type = "$(class.c_name)_t *"
            endif
        endnew
    endif
    for my.method.argument
        copy argument to my.method as tmp_arg
    endfor

    my.out = "$(my.method->return.c_type:)\n"
    my.out += "    $(class.c_name)_$(my.method.c_name) "
    my.out += _c_method_arglist(my.method)
    for my.method.tmp_arg as argument
        if argument.type = "format"
            # Next argument is the format list
            my.method.format_index = index()
        endif
    endfor
    for my.method.tmp_arg
        delete tmp_arg
    endfor
    return my.out
endfunction

#
# Construct the string for a callback typedef in a C header
#
function c_callback_typedef (method)
    my.out = "typedef $(my.method->return.c_type:) "
    my.out += "($(class.c_name)_$(my.method.c_name)) ("
    my.out += "\n    "
    for my.method.argument
        my.out += argument.c_type?""
        if !regexp.match ("\\*$", argument.c_type?"")
            my.out += " "
        endif
        my.out += argument.c_name?""
        if !last ()
            my.out += ", "
        endif
    endfor
    my.out += ");"
    return my.out
endfunction


# Resolve each class using the functions written above.
#
# This includes creating implicit XML entities as well as resolving both
# the semantic and the C-specific attributes of all entities
#
# Other code generation scripts can depend on these being fully resolved here,
# though they should NOT depend on attributes resolved by other generators.
#
for project.main
    if project.use_cxx
        main.source = "src/$(main.name:c).cc"
    else
        main.source = "src/$(main.name:c).c"
    endif
    skeleton_main_source ()
endfor

for project.actor
    if scope = "private"
        actor.header = "src/$(actor.name:c).h"
    else
        actor.header = "include/$(actor.name:c).h"
    endif
    if project.use_cxx
        actor.source = "src/$(actor.name:c).cc"
    else
        actor.source = "src/$(actor.name:c).c"
    endif
    skeleton_actor_header ()
    skeleton_actor_source ()
endfor

for project.class
    if scope = "private"
        class.header = "src/$(class.name:c).h"
    else
        class.header = "include/$(class.name:c).h"
    endif
    if project.use_cxx
        class.source = "src/$(class.name:c).cc"
    else
        class.source = "src/$(class.name:c).c"
    endif

    if defined (class.api)
        resolve_c_class (class)
    else
        # If there is no API model for this class,
        # all we can do is resolve the name and state
        class.c_name = "$(class.name:c)"
        set_state (class, "draft")
    endif
endfor

if count (project.class, !private & !draft)
    project.stable = 1
else
    project.stable = 0
endif

# Resolve the dependencies of the classes from this project and load their APIs
#
for project.class
    if defined (class.api)
        resolve_class_dependencies (class)
    endif
endfor

# Resolve C-related properties of the dependencies API models, find further
# dependencies, load their APIs and repeat if further dependencies have been
# found.
#
if defined (project->dependencies) & count (project->dependencies.class)
    while count (project->dependencies.class, !class.resolved)
        for project->dependencies.class where !class.resolved
            resolve_class_dependencies (class)
            class.resolved = 1
        endfor
    endwhile
endif