Backend class

Author: scivision

+stdlib/+dotnet/get_hostname.m renamed to +stdlib/+dotnet/hostname.m

@@ -1,7 +1,7 @@
 %% DOTNET.GET_HOSTNAME get the computer network hostname
 % not necessary FQDN
 
-function n = get_hostname()
+function n = hostname()
 
 n = char(System.Environment.MachineName);
 % https://learn.microsoft.com/en-us/dotnet/api/system.environment.machinename

+stdlib/+java/get_hostname.m renamed to +stdlib/+java/hostname.m

@@ -1,4 +1,4 @@
-function n = get_hostname()
+function n = hostname()
 
 n = char(java.net.InetAddress.getLocalHost().getHostName());
 

+stdlib/+python/get_hostname.m renamed to +stdlib/+python/hostname.m

@@ -1,4 +1,4 @@
-function n = get_hostname()
+function n = hostname()
 
 try
   n = char(py.socket.gethostname());

+stdlib/+sys/device.m

@@ -15,7 +15,7 @@
   c0 = 'pwsh -c "(Get-CimInstance -ClassName Win32_Volume -Filter \"DriveLetter = ''';
   c1 = stdlib.root_name(stdlib.absolute(p));
   c2 = '''\").SerialNumber"';
-  cmd = [c0, c1, c2];
+  cmd = strcat(c0, c1, c2);
 elseif ismac()
   cmd = sprintf('stat -f %%d "%s"', p);
 else

+stdlib/+sys/get_hostname.m renamed to +stdlib/+sys/hostname.m

@@ -1,4 +1,4 @@
-function [n, cmd] = get_hostname()
+function [n, cmd] = hostname()
 
 cmd = 'hostname';
 [s, n] = system(cmd);

+stdlib/Backend.m

@@ -0,0 +1,128 @@
+classdef Backend < matlab.mixin.SetGet
+
+properties (Constant)
+optionalBackends = ["python", "dotnet", "java"]
+namespace = "stdlib"
+end
+
+properties
+backends string = ["native", "legacy", "sys"]
+func
+backend
+end
+
+methods
+
+function self = Backend(functionName, backendReq)
+arguments
+  functionName (1,1) string = ""
+  backendReq (1,:) string = string.empty
+end
+
+for i = 1:numel(self.optionalBackends)
+  f = str2func(sprintf('%s.has_%s', self.namespace, self.optionalBackends(i)));
+  if f()
+    self.backends = [self.optionalBackends(i), self.backends];
+  end
+end
+
+if any(strlength(functionName))
+  self.func = self.getFunc(functionName, backendReq);
+end
+end
+
+
+function m = select(self, functionName, backendReq)
+arguments
+  self
+  functionName (1,1) string
+  backendReq (1,:) string = string.empty
+end
+
+if ~any(strlength(backendReq))
+  backendReq = self.backends;
+end
+
+for m = backendReq
+  switch m
+    case 'dotnet'
+      if ~any(ismember(self.backends, 'dotnet'))
+        continue
+      end
+
+      switch functionName
+        case {'create_symlink', 'ram_total', 'read_symlink'}
+          if stdlib.dotnet_api() < 6, continue, end
+        case {'get_owner', 'is_admin'}
+          if isunix(), continue, end
+      end
+    case 'java'
+      if ~any(ismember(self.backends, 'java'))
+        continue
+      end
+
+      switch functionName
+        case {'device', 'hard_link_count' , 'inode', 'is_admin'}
+          if ispc(), continue, end
+      end
+    case 'python'
+      if ~any(ismember(self.backends, 'python'))
+        continue
+      end
+
+      switch functionName
+        case {'filesystem_type', 'ram_total', 'ram_free'}
+          if ~stdlib.python.has_psutil(); continue, end
+        case {'cpu_load', 'get_owner'}
+          if ispc(), continue, end
+        case 'is_admin'
+          if ispc() || stdlib.matlabOlderThan('R2024a'), continue, end
+      end
+    case 'native'
+
+      switch functionName
+        case 'create_symlink'
+          if stdlib.matlabOlderThan('R2024b') || (ispc() && stdlib.matlabOlderThan('R2025a'))
+            continue
+          end
+        case {'is_symlink', 'read_symlink'}
+          if stdlib.matlabOlderThan('R2024b'), continue, end
+        case {'get_permissions', 'set_permissions'}
+          if stdlib.matlabOlderThan('R2025a'), continue, end
+      end
+  end
+
+  if ~isempty(which(sprintf('%s.%s.%s', self.namespace, m, functionName)))
+    return
+  end
+
+end
+
+m = string.empty;
+
+end
+
+
+function func = getFunc(self, functionName, backendReq)
+arguments
+  self
+  functionName (1,1) string
+  backendReq (1,:) string = string.empty
+end
+
+if isscalar(backendReq)
+  self.backend = backendReq;
+else
+  self.backend = self.select(functionName, backendReq);
+end
+
+if isempty(self.backend)
+  error('No backend found for %s.%s', self.namespace, functionName);
+else
+  func = str2func(sprintf('%s.%s.%s', self.namespace, self.backend, functionName));
+end
+
+end
+
+end
+end

+stdlib/cpu_arch.m

@@ -1,12 +1,17 @@
 %% CPU_ARCH get the CPU architecture
+%
+%%% Outputs
+% * a: Returns the CPU architecture as a string.
+% * b: backend used
 
-function a = cpu_arch(backend)
+function [a, b] = cpu_arch(backend)
 arguments
   backend (1,:) string = ["java", "dotnet", "native"]
 end
 
-fun = hbackend(backend, "cpu_arch");
+o = stdlib.Backend(mfilename(), backend);
+a = o.func();
 
-a = fun();
+b = o.backend;
 
 end

+stdlib/cpu_load.m

@@ -1,18 +1,20 @@
 %% CPU_LOAD get total physical CPU load
 %
-% Returns the "recent cpu usage" for the whole system.
+%%% Outputs
+% * a: Returns the "recent cpu usage" for the whole system.
+% * b: backend used
 %
 % This value is a double greater than 0.
 % If the system recent cpu usage is not available, the backend returns a negative or NaN value.
 
-function L = cpu_load(backend)
+function [a, b] = cpu_load(backend)
 arguments
   backend (1,:) string = ["java", "python", "sys"]
 end
 
-fun = hbackend(backend, "cpu_load");
-
-L = fun();
+o = stdlib.Backend(mfilename(), backend);
+a = o.func();
 
+b = o.backend;
 
 end

+stdlib/create_symlink.m

@@ -14,8 +14,8 @@
   backend (1,:) string = ["native", "dotnet", "python", "sys"]
 end
 
-[fun, b] = hbackend(backend, "create_symlink");
-
-ok = fun(target, link);
+o = stdlib.Backend(mfilename(), backend);
+ok = o.func(target, link);
 
+b = o.backend;
 end

+stdlib/device.m

@@ -12,8 +12,8 @@
   backend (1,:) string = ["java", "python", "sys"]
 end
 
-[fun, b] = hbackend(backend, "device");
-
-i = fun(file);
+o = stdlib.Backend(mfilename(), backend);
+i = o.func(file);
 
+b = o.backend;
 end