Merge pull request #1658 from aarroyoc/copy_file

Add predicate file_copy/2 in library(files)

build/instructions_template.rs

@@ -262,6 +262,8 @@ enum SystemClauseType {
     DeleteFile,
     #[strum_discriminants(strum(props(Arity = "2", Name = "$rename_file")))]
     RenameFile,
+    #[strum_discriminants(strum(props(Arity = "2", Name = "$file_copy")))]
+    FileCopy,
     #[strum_discriminants(strum(props(Arity = "2", Name = "$working_directory")))]
     WorkingDirectory,
     #[strum_discriminants(strum(props(Arity = "1", Name = "$delete_directory")))]
@@ -1607,6 +1609,7 @@ fn generate_instruction_preface() -> TokenStream {
                     &Instruction::CallMakeDirectoryPath(_) |
                     &Instruction::CallDeleteFile(_) |
                     &Instruction::CallRenameFile(_) |
+		    &Instruction::CallFileCopy(_) |
                     &Instruction::CallWorkingDirectory(_) |
                     &Instruction::CallDeleteDirectory(_) |
                     &Instruction::CallPathCanonical(_) |
@@ -1819,6 +1822,7 @@ fn generate_instruction_preface() -> TokenStream {
                     &Instruction::ExecuteMakeDirectoryPath(_) |
                     &Instruction::ExecuteDeleteFile(_) |
                     &Instruction::ExecuteRenameFile(_) |
+		    &Instruction::ExecuteFileCopy(_) |
                     &Instruction::ExecuteWorkingDirectory(_) |
                     &Instruction::ExecuteDeleteDirectory(_) |
                     &Instruction::ExecutePathCanonical(_) |

src/lib/files.pl

@@ -70,8 +70,9 @@ In this library, directories and files are represented as
                   file_exists/1,
                   directory_exists/1,
                   delete_file/1,
-				  rename_file/2,
-				  delete_directory/1,
+		  rename_file/2,
+		  file_copy/2,
+		  delete_directory/1,
                   make_directory/1,
                   make_directory_path/1,
                   working_directory/2,
@@ -150,6 +151,14 @@ rename_file(File, Renamed) :-
         must_be(chars, Renamed),
         '$rename_file'(File, Renamed).
 
+%% file_copy(+File, +Copied).
+%
+% Succeeds if File is copied to Copied
+file_copy(File, Copied) :-
+	file_must_exist(File, file_copy/2),
+	must_be(chars, Copied),
+	'$file_copy'(File, Copied).
+
 %% delete_directory(+Directory).
 %
 % Succeeds if Directory is deleted from the current system.

src/machine/dispatch.rs

@@ -3533,6 +3533,14 @@ impl Machine {
                     self.rename_file();
                     step_or_fail!(self, self.machine_st.p = self.machine_st.cp);
                 }
+		&Instruction::CallFileCopy(_) => {
+		    self.file_copy();
+		    step_or_fail!(self, self.machine_st.p += 1);
+		}
+		&Instruction::ExecuteFileCopy(_) => {
+		    self.file_copy();
+		    step_or_fail!(self, self.machine_st.p = self.machine_st.cp);
+		}
                 &Instruction::CallWorkingDirectory(_) => {
                     try_or_throw!(self.machine_st, self.working_directory());
                     step_or_fail!(self, self.machine_st.p += 1);

src/machine/system_calls.rs

@@ -1653,6 +1653,19 @@ impl Machine {
         self.machine_st.fail = true;
     }
 
+    #[inline(always)]
+    pub(crate) fn file_copy(&mut self) {
+	if let Some(file) = self.machine_st.value_to_str_like(self.machine_st.registers[1]) {
+	    if let Some(copied) = self.machine_st.value_to_str_like(self.machine_st.registers[2]) {
+		if fs::copy(file.as_str(), copied.as_str()).is_ok() {
+		    return;
+		}
+	    }
+	}
+
+	self.machine_st.fail = true;
+    }
+
     #[inline(always)]
     pub(crate) fn delete_directory(&mut self) {
         if let Some(dir) = self.machine_st.value_to_str_like(self.machine_st.registers[1]) {