lint / docs

Author: scivision

+stdlib/file_size.m

@@ -3,7 +3,7 @@
 %%% Inputs
 % * p: path to file
 %%% Outputs
-% * s: size in bytes, or empty if file does not exist
+% * s: size in bytes; NaN if file does not exist
 
 function s = file_size(p)
 arguments

+stdlib/is_executable_binary.m

@@ -1,44 +1,71 @@
-function y = is_executable_binary(filename)
 % IS_EXECUTABLE_BINARY Check if a file is an executable binary by examining magic numbers
 %
 % NOTE: on Unix-like operating systems, often times what users run thinking
 % it's a "program" is actually a shell script invoking a binary with
 % options.
 %    fullfile(matlabroot, 'bin/matlab')
 % is a shell script and thus is FALSE for this function.
+%
+% Inputs:
+% * filename: path to file
+% Outputs:
+% * y: true if the file is an executable binary, false otherwise
+%
+% This function checks the magic number of the file to determine if it is
+% an executable binary. It supports Windows (PE), macOS (Mach-O), and Linux
+% (ELF) formats.
+
+function y = is_executable_binary(filename)
+arguments
+  filename {mustBeTextScalar}
+end
 
 y = false;
 
 fid = fopen(filename, 'rb');
-if fid < 0, return, end
+if fid < 0
+  return
+end
 
 N = 4;
-if ispc(), N = 2; end
+if ispc()
+  N = 2;
+end
 
 magic = fread(fid, N, 'uint8').';
 fclose(fid);
-if numel(magic) < N, return, end
+
+if numel(magic) == N
+  y = check_magic(magic);
+end
+
+end
+
+
+function y = check_magic(magic)
 
 if ispc()
-    y = isequal(magic(1:2), [0x4d, 0x5a]);
-    % Check for PE magic number (MZ)
+  y = isequal(magic(1:2), [0x4d, 0x5a]);
+% Check for PE magic number (MZ)
 elseif ismac()
-    % Check for Mach-O magic number
-    feedface = [0xFE, 0xED, 0xFA, 0xCE];
-    feedfacf = [0xFE, 0xED, 0xFA, 0xCF];
-    cafebabe = [0xCA, 0xFE, 0xBA, 0xBE];
-    cafebabf = [0xCA, 0xFE, 0xBA, 0xBF];
-    for a = {feedface, fliplr(feedface), ...
-             feedfacf, fliplr(feedfacf), ...
-             cafebabe, fliplr(cafebabe), ...
-             cafebabf, fliplr(cafebabf)}
-
-       y = isequal(magic, a{1});
-       if y, return, end
+  % Check for Mach-O magic number
+  feedface = [0xFE, 0xED, 0xFA, 0xCE];
+  feedfacf = [0xFE, 0xED, 0xFA, 0xCF];
+  cafebabe = [0xCA, 0xFE, 0xBA, 0xBE];
+  cafebabf = [0xCA, 0xFE, 0xBA, 0xBF];
+  for a = {feedface, fliplr(feedface), ...
+           feedfacf, fliplr(feedfacf), ...
+           cafebabe, fliplr(cafebabe), ...
+           cafebabf, fliplr(cafebabf)}
+
+    y = isequal(magic, a{1});
+    if y
+      return
     end
+  end
 else
-    % Check for ELF magic number (0x7f followed by 'ELF')
-    y = isequal(magic, [0x7f, 0x45, 0x4c, 0x46]);
+  % Check for ELF magic number (0x7f followed by 'ELF')
+  y = isequal(magic, [0x7f, 0x45, 0x4c, 0x46]);
 end
 
 end