file_checksum: sys backend

choose_method => hbackend

Author: scivision

+stdlib/+dotnet/file_checksum.m

@@ -0,0 +1,27 @@
+%% DOTNET.FILE_CHECKSUM compute checksum has of file
+
+% Ref: https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/security/MessageDigest.html#getInstance(java.lang.String)
+
+function hash = file_checksum(file, hash_method)
+
+if any(strcmp(hash_method, {'sha256', 'SHA256'}))
+  hash_method = "SHA-256";
+end
+
+file_chunk = 10e6;  % arbitrary (bytes) didn't seem to be very sensitive for speed
+
+fid = fopen(file, 'r');
+assert(fid > 1, "could not open file %s", file)
+
+inst = System.Security.Cryptography.HashAlgorithm.Create(hash_method);
+while ~feof(fid)
+  % https://docs.microsoft.com/en-us/dotnet/api/system.security.cryptography.hashalgorithm.computehash
+  inst.ComputeHash(fread(fid, file_chunk, '*uint8'));
+end
+h = uint8(inst.Hash);
+
+fclose(fid);
+
+hash = sprintf('%.2x', h);
+
+end

+stdlib/+java/file_checksum.m

@@ -0,0 +1,27 @@
+%% JAVA.FILE_CHECKSUM compute checksum hash of file
+% Ref: https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/security/MessageDigest.html#getInstance(java.lang.String)
+
+function hash = file_checksum(file, hash_method)
+
+if any(strcmp(hash_method, {'sha256', 'SHA256'}))
+  hash_method = "SHA-256";
+end
+
+file_chunk = 10e6;  % arbitrary (bytes) didn't seem to be very sensitive for speed
+
+fid = fopen(file, 'r');
+assert(fid > 1, "could not open file %s", file)
+
+inst = javaMethod("getInstance", "java.security.MessageDigest", hash_method);
+while ~feof(fid)
+  % https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/security/MessageDigest.html#update(byte)
+  inst.update(fread(fid, file_chunk, '*uint8'));
+end
+% https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/security/MessageDigest.html#digest()
+h = typecast(inst.digest, 'uint8');
+
+fclose(fid);
+
+hash = sprintf('%.2x', h);
+
+end

+stdlib/+sys/file_checksum.m

@@ -0,0 +1,37 @@
+%% SYS.FILE_CHECKSUM compute checksum of file
+function hash = file_checksum(file, hash_method)
+
+switch lower(hash_method)
+  case {"sha-256", "sha256"}
+    if ismac()
+      cmd = "shasum --algorithm 256 --binary " + file;
+    elseif ispc()
+      cmd = "CertUtil -hashfile " + file + " SHA256";
+    else
+      cmd = "sha256sum --binary " + file;
+    end
+  case "md5"
+    if ismac()
+      cmd = "md5 -r " + file;
+    elseif ispc()
+      cmd = "CertUtil -hashfile " + file + " MD5";
+    else
+      cmd = "md5sum " + file;
+    end
+  otherwise, error('unhandled hash method %s', hash_method)
+end
+
+[s, m] = system(cmd);
+
+assert(s == 0, "failed to compute SHA256 hash of %s: %s", file, m)
+
+switch lower(hash_method)
+  case {"sha-256", "sha256"}
+    hash = regexp(m, '^\w{64}','match','once','lineanchors');
+    assert(strlength(hash)==64, 'SHA256 hash is 64 characters')
+  case "md5"
+    hash = regexp(m, '^\w{32}','match','once','lineanchors');
+    assert(strlength(hash)==32, 'MD5 hash is 32 characters')
+end
+
+end

+stdlib/canonical.m

@@ -12,14 +12,14 @@
 %%% Outputs
 % * c: canonical path, if determined
 
-function c = canonical(p, strict, method)
+function c = canonical(p, strict, backend)
 arguments
   p {mustBeTextScalar}
   strict (1,1) logical = false
-  method (1,:) string = ["native", "legacy"]
+  backend (1,:) string = ["native", "legacy"]
 end
 
-fun = choose_method(method, "canonical", 'R2024a');
+fun = hbackend(backend, "canonical", 'R2024a');
 
 c = fun(p, strict);
 

+stdlib/cpu_arch.m

@@ -1,11 +1,11 @@
 %% CPU_ARCH get the CPU architecture
 
-function a = cpu_arch(method)
+function a = cpu_arch(backend)
 arguments
-  method (1,:) string = ["java", "dotnet", "native"]
+  backend (1,:) string = ["java", "dotnet", "native"]
 end
 
-fun = choose_method(method, "cpu_arch");
+fun = hbackend(backend, "cpu_arch");
 
 a = fun();
 

+stdlib/cpu_load.m

@@ -3,14 +3,14 @@
 % Returns the "recent cpu usage" for the whole system.
 %
 % This value is a double greater than 0.
-% If the system recent cpu usage is not available, the method returns a negative or NaN value.
+% If the system recent cpu usage is not available, the backend returns a negative or NaN value.
 
-function L = cpu_load(method)
+function L = cpu_load(backend)
 arguments
-  method (1,:) string = ["java", "python", "sys"]
+  backend (1,:) string = ["java", "python", "sys"]
 end
 
-fun = choose_method(method, "cpu_load");
+fun = hbackend(backend, "cpu_load");
 
 L = fun();
 

+stdlib/create_symlink.m

@@ -6,14 +6,14 @@
 %%% Outputs
 % * ok: true if successful
 
-function ok = create_symlink(target, link, method)
+function ok = create_symlink(target, link, backend)
 arguments
   target {mustBeTextScalar}
   link {mustBeTextScalar}
-  method (1,:) string = ["native", "dotnet", "python", "sys"]
+  backend (1,:) string = ["native", "dotnet", "python", "sys"]
 end
 
-fun = choose_method(method, "create_symlink", 'R2024b');
+fun = hbackend(backend, "create_symlink", 'R2024b');
 
 ok = fun(target, link);
 

+stdlib/device.m

@@ -1,12 +1,12 @@
 %% DEVICE filesystem device index of path
 
-function i = device(file, method)
+function i = device(file, backend)
 arguments
   file {mustBeTextScalar}
-  method (1,:) string = ["java", "python", "sys"]
+  backend (1,:) string = ["java", "python", "sys"]
 end
 
-fun = choose_method(method, "device");
+fun = hbackend(backend, "device");
 i = fun(file);
 
 end

+stdlib/disk_available.m

@@ -4,13 +4,13 @@
 %
 % Ref: https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/io/File.html#getUsableSpace()
 
-function f = disk_available(filepath, method)
+function f = disk_available(filepath, backend)
 arguments
   filepath {mustBeTextScalar}
-  method (1,:) string = ["java", "dotnet", "python", "sys"]
+  backend (1,:) string = ["java", "dotnet", "python", "sys"]
 end
 
-fun = choose_method(method, "disk_available");
+fun = hbackend(backend, "disk_available");
 
 f = fun(filepath);
 

+stdlib/disk_capacity.m

@@ -2,13 +2,13 @@
 %
 % example:  stdlib.disk_capacity('/')
 
-function f = disk_capacity(filepath, method)
+function f = disk_capacity(filepath, backend)
 arguments
   filepath {mustBeTextScalar}
-  method (1,:) string = ["java", "dotnet", "python", "sys"]
+  backend (1,:) string = ["java", "dotnet", "python", "sys"]
 end
 
-fun = choose_method(method, "disk_capacity");
+fun = hbackend(backend, "disk_capacity");
 
 f = fun(filepath);