%% Integrate External C Functions That Pass Arguments That Have Inherited Dimensions
% This example shows how to use the Legacy Code Tool to integrate legacy C 
% functions whose arguments have inherited dimensions.
%
% With the Legacy Code Tool, you can:
%
% * Provide the legacy function specification.
% * Generate a C-MEX S-function that calls the legacy code during
% simulation.
% * Compile and build the generated S-function for simulation.
% * Generate a TLC block file and optional rtwmakecfg.m file that specifies
% how the generated code for a model calls the legacy code.

%   Copyright 1990-2015 The MathWorks, Inc.

%% Provide the Legacy Function Specification
% Legacy Code Tool functions take a specific data structure or array of
% structures as the argument. You can initialize the data structure by
% calling the function legacy_code() using 'initialize' as the first input.
% After initializing the structure, assign its properties to values
% corresponding to the legacy code being integrated. For detailed help on
% the properties, call <matlab:legacy_code('help') legacy_code('help')>. The 
% prototypes of the legacy functions being called in this example are:
%
% * void mat_add(real_T *u1, real_T *u2, int32_T nbRows, int32_T nbCols, real_T *y1)
% * void mat_mult(real_T *u1, real_T *u2, int32_T nbRows1, int32_T nbCols1, int32_T nbCols2, real_T *y1)
%
% real_T is a typedef to double, and int32_T is a typedef to a
% 32-bit integer.  The legacy source code is in the
% files <matlab:rtwdemo_lct_util('edit','rtwdemo_lct_src/mat_ops.h') mat_ops.h>, and
% <matlab:rtwdemo_lct_util('edit','rtwdemo_lct_src/mat_ops.c') mat_ops.c>.

defs = [];

% rtwdemo_sfun_mat_add
def = legacy_code('initialize');
def.SFunctionName = 'rtwdemo_sfun_mat_add';
def.OutputFcnSpec = ['void mat_add(double u1[][], double u2[][], ' ...
                   'int32 u3, int32 u4, double y1[size(u1,1)][size(u1,2)])'];
def.HeaderFiles   = {'mat_ops.h'};
def.SourceFiles   = {'mat_ops.c'};
def.IncPaths      = {'rtwdemo_lct_src'}; 
def.SrcPaths      = {'rtwdemo_lct_src'}; 
defs = [defs; def];

% rtwdemo_sfun_mat_mult
def = legacy_code('initialize');
def.SFunctionName = 'rtwdemo_sfun_mat_mult';
def.OutputFcnSpec =  ['void mat_mult(double u1[p1][p2], double u2[p2][p3], '...
                   'int32 p1, int32 p2, int32 p3, double y1[p1][p3])'];
def.HeaderFiles   = {'mat_ops.h'};
def.SourceFiles   = {'mat_ops.c'};
def.IncPaths      = {'rtwdemo_lct_src'}; 
def.SrcPaths      = {'rtwdemo_lct_src'}; 
defs = [defs; def];

%%  Generate S-Functions for Simulation
% To generate C-MEX S-functions according to the description provided by
% the input argument 'defs', call the function legacy_code() again with the
% first input set to 'sfcn_cmex_generate'. The S-functions call the legacy
% functions during simulation.
% The source code for the S-function is in the files
% <matlab:rtwdemo_lct_util('edit','rtwdemo_sfun_mat_add.c') rtwdemo_sfun_mat_add.c> and
% <matlab:rtwdemo_lct_util('edit','rtwdemo_sfun_mat_mult.c') rtwdemo_sfun_mat_mult.c>.

legacy_code('sfcn_cmex_generate', defs);

%% Compile the Generated S-Functions for Simulation
% After you generate the C-MEX S-function source files, to compile the
% S-functions for simulation with Simulink(R), call the function
% legacy_code() again with the first input set to 'compile'.

legacy_code('compile', defs);

%% Generate TLC Block Files for Code Generation
% After you compile the S-functions and use them in simulation, you can
% call the function legacy_code() again with the first input set to
% 'sfcn_tlc_generate' to generate TLC block files. Block files specify how
% the generated code for a model calls the legacy code. If you do not
% generate TLC block files and you try to generate code for a model that
% includes the S-functions, code generation fails. The TLC block files for
% the S-functions are
% <matlab:rtwdemo_lct_util('edit','rtwdemo_sfun_mat_add.tlc') rtwdemo_sfun_mat_add.tlc> and
% <matlab:rtwdemo_lct_util('edit','rtwdemo_sfun_mat_mult.tlc') rtwdemo_sfun_mat_mult.tlc>.

legacy_code('sfcn_tlc_generate', defs);

%% Generate an rtwmakecfg.m File for Code Generation
% After you create the TLC block files, you can call the function
% legacy_code() again with the first input set to 'rtwmakecfg_generate' to
% generate an rtwmakecfg.m file to support code generation. If the required
% source and header files for the S-functions are not in the same folder as
% the S-functions, and you want to add these dependencies in the makefile
% produced during code generation, generate the rtwmakecfg.m file.

legacy_code('rtwmakecfg_generate', defs);

%% Generate Masked S-Function Blocks for Calling the Generated S-Functions
% After you compile the C-MEX S-function source, you can call the function
% legacy_code() again with the first input set to 'slblock_generate' to
% generate masked S-function blocks that call the S-functions.  The
% software places the blocks in a new model. From there you can copy them
% to an existing model

legacy_code('slblock_generate', defs);

%% Show the Generated Integration with Legacy Code
% The model <matlab:rtwdemo_lct_inherit_dims rtwdemo_lct_inherit_dims> 
% shows integration of the model with the legacy
% code.  The subsystem TestMatOps serves as a harness for the calls to the
% legacy C functions, with unit delays serving to store the previous 
% output values.

open_system('rtwdemo_lct_inherit_dims')
open_system('rtwdemo_lct_inherit_dims/TestMatOps')
sim('rtwdemo_lct_inherit_dims')
