vm: implemented reading/writing files in diskio

compiler/res/prog8lib/virtual/diskio.p8

@@ -1,4 +1,8 @@
-; file I/O routines. (partially implemented)
+; File I/O routines for the VM target
+;
+; NOTE: not all is implemented.
+; NOTE: some calls are slightly different from the "official" diskio library because for example,
+;       here we cannot deal with multiple return values.
 
 %import textio
 %import syslib
@@ -59,37 +63,86 @@ diskio {
         ;    NOTE: the default input isn't yet set to this logical file, you must use reset_read_channel() to do this,
         ;          if you're going to read from it yourself instead of using f_read()!
 
-        txt.print("@TODO: f_open\n")
-        return false
+        %ir {{
+            loadm.w r65535,diskio.f_open.filenameptr
+            syscall 52 (r65535.w): r0.b
+            returnr.b r0
+        }}
     }
 
     sub f_read(uword bufferpointer, uword num_bytes) -> uword {
         ; -- read from the currently open file, up to the given number of bytes.
         ;    returns the actual number of bytes read.  (checks for End-of-file and error conditions)
-        txt.print("@TODO: f_read\n")
-        return 0
+        uword actual
+        repeat num_bytes {
+            %ir {{
+                syscall 54 (): r0.w
+                storem.w r0,$ff02
+            }}
+            if cx16.r0H==0
+                return actual
+            @(bufferpointer) = cx16.r0L
+            bufferpointer++
+            actual++
+        }
+        return actual
     }
 
     sub f_read_all(uword bufferpointer) -> uword {
         ; -- read the full contents of the file, returns number of bytes read.
         ;    It is assumed the file size is less than 64 K.
-        txt.print("@TODO: f_read_all\n")
-        return 0
+        uword actual
+        repeat {
+            %ir {{
+                syscall 54 (): r0.w
+                storem.w r0,$ff02
+            }}
+            if cx16.r0H==0
+                return actual
+            @(bufferpointer) = cx16.r0L
+            bufferpointer++
+            actual++
+        }
     }
 
     sub f_readline(uword bufptr) -> ubyte {
         ; Routine to read text lines from a text file. Lines must be less than 255 characters.
         ; Reads characters from the input file UNTIL a newline or return character (or EOF).
         ; The line read will be 0-terminated in the buffer (and not contain the end of line character).
-        ; The length of the line is returned in Y. Note that an empty line is okay and is length 0!
-        ; This routine is not able here to return the status as well in a secondary return value, so you have to do that yourself.
-        txt.print("@TODO: f_readline\n")
-        return 0
+        ; The length of the line is returned. Note that an empty line is okay and is length 0!
+        ; The success status is returned in the Carry flag instead: C set = success, C clear = failure/endoffile
+        ubyte size
+        repeat {
+            %ir {{
+                syscall 54 (): r0.w
+                storem.w r0,$ff02
+            }}
+
+            if cx16.r0H==0 {
+                sys.clear_carry()
+                return size
+            } else {
+                if cx16.r0L == '\n' or cx16.r0L=='\r' {
+                    @(bufptr) = 0
+                    sys.set_carry()
+                    return size
+                }
+                @(bufptr) = cx16.r0L
+                bufptr++
+                size++
+                if_z {
+                    @(bufptr) = 0
+                    return 255
+                }
+            }
+        }
     }
 
     sub f_close() {
         ; -- end an iterative file loading session (close channels).
-        txt.print("@TODO: f_close\n")
+        %ir {{
+            syscall 56 ()
+        }}
     }
 
 
@@ -102,20 +155,35 @@ diskio {
         ;    (for example, if it already exists). This is different than f_open()!
         ;    To be 100% sure if this call was successful, you have to use status()
         ;    and check the drive's status message!
-        txt.print("@TODO: f_open_w\n")
-        return false
+        %ir {{
+            loadm.w r65535,diskio.f_open_w.filenameptr
+            syscall 53 (r65535.w): r0.b
+            returnr.b r0
+        }}
     }
 
     sub f_write(uword bufferpointer, uword num_bytes) -> bool {
         ; -- write the given number of bytes to the currently open file
         ;    you can call this multiple times to append more data
-        txt.print("@TODO: f_write\n")
+        repeat num_bytes {
+            %ir {{
+                loadm.w r0,diskio.f_write.bufferpointer
+                loadi.b r1,r0
+                syscall 55 (r1.b): r0.b
+                storem.b r0,$ff02
+            }}
+            if cx16.r0L==0
                 return false
+            bufferpointer++
+        }
+        return true
     }
 
     sub f_close_w() {
         ; -- end an iterative file writing session (close channels).
-        txt.print("@TODO: f_close_w\n")
+        %ir {{
+            syscall 57 ()
+        }}
     }
 
 
@@ -123,23 +191,34 @@ diskio {
 
     sub chdir(str path) {
         ; -- change current directory.
-        txt.print("@TODO: chdir\n")
+        %ir {{
+            loadm.w r65535,diskio.chdir.path
+            syscall 50 (r65535.w)
+        }}
     }
 
     sub mkdir(str name) {
         ; -- make a new subdirectory.
-        txt.print("@TODO: mkdir\n")
+        %ir {{
+            loadm.w r65535,diskio.mkdir.name
+            syscall 49 (r65535.w)
+        }}
     }
 
     sub rmdir(str name) {
         ; -- remove a subdirectory.
-        txt.print("@TODO: rmdir\n")
+        %ir {{
+            loadm.w r65535,diskio.rmdir.name
+            syscall 51 (r65535.w)
+        }}
     }
 
     sub curdir() -> uword {
         ; return current directory name or 0 if error
-        txt.print("@TODO: curdir\n")
-        return 0
+        %ir {{
+            syscall 48 (): r0.w
+            returnr.w r0
+        }}
     }
 
     sub status() -> str {

docs/source/todo.rst

@@ -59,7 +59,7 @@ Libraries:
 - fix the problems in atari target, and flesh out its libraries.
 - c128 target: make syslib more complete (missing kernal routines)?
 - pet32 target: make syslib more complete (missing kernal routines)?
-- VM: implement more diskio support
+- VM: implement the last diskio support (file listings)
 
 
 Optimizations:

examples/test.p8

@@ -1,11 +1,51 @@
 %import textio
+%import diskio
 %option no_sysinit
 %zeropage basicsafe
 
 main {
     sub start() {
-        alias print = txt.print
-        alias zz=print
-        zz("chained")
+        txt.lowercase()
+
+        uword buffer = memory("buffer", 16000, 0)
+        uword line = 0
+
+        if diskio.f_open("gradlew.bat") {
+            uword size = diskio.f_read(buffer, 1000)
+            txt.print_uw(size)
+            txt.nl()
+            diskio.f_close()
+        }
+
+        if diskio.f_open("gradlew.bat") {
+            size = diskio.f_read_all(buffer)
+            txt.print_uw(size)
+            txt.nl()
+
+            diskio.f_close()
+        }
+
+        if diskio.f_open("gradlew.bat") {
+            ubyte linesize, status
+            repeat {
+                linesize = diskio.f_readline(buffer)
+                if_cs {
+                    line++
+                } else break
+            }
+            diskio.f_close()
+
+            txt.print_uw(line)
+            txt.nl()
+        }
+
+        if diskio.f_open_w("result.txt") {
+            void diskio.f_write("line 1\n", 7)
+            void diskio.f_write("line 2\n", 7)
+            void diskio.f_write("line 3\n", 7)
+            diskio.f_close_w()
         }
     }
+
+
+}

virtualmachine/src/prog8/vm/SysCalls.kt

@@ -3,12 +3,11 @@ package prog8.vm
 import prog8.intermediate.FunctionCallArgs
 import prog8.intermediate.IRDataType
 import java.io.File
-import kotlin.io.path.Path
-import kotlin.io.path.listDirectoryEntries
+import kotlin.io.path.*
 import kotlin.math.*
 
 /*
-SYSCALLS:
+SYSCALLS:     DO NOT RENUMBER THESE OR YOU WILL BREAK EXISTING CODE
 
 0 = reset ; resets system
 1 = exit ; stops program and returns statuscode from r0.w
@@ -58,6 +57,16 @@ SYSCALLS:
 45 = directory
 46 = getconsolesize
 47 = memcmp
+48 = CURDIR
+49 = MKDIR
+50 = CHDIR
+51 = RMDIR
+52 = OPEN_FILE
+53 = OPEN_FILE_WRITE
+54 = READ_FILE_BYTE
+55 = WRITE_FILE_BYTE
+56 = CLOSE_FILE
+57 = CLOSE_FILE_WRITE
 */
 
 enum class Syscall {
@@ -108,7 +117,17 @@ enum class Syscall {
     RENAME,
     DIRECTORY,
     GETGONSOLESIZE,
-    MEMCMP
+    MEMCMP,
+    CURDIR,
+    MKDIR,
+    CHDIR,
+    RMDIR,
+    OPEN_FILE,
+    OPEN_FILE_WRITE,
+    READ_FILE_BYTE,
+    WRITE_FILE_BYTE,
+    CLOSE_FILE,
+    CLOSE_FILE_WRITE,
     ;
 
     companion object {
@@ -517,7 +536,7 @@ object SysCalls {
             }
             Syscall.DIRECTORY -> {
                 // no arguments
-                val directory = Path(".")
+                val directory = Path("")
                 println("Directory listing for ${directory.toAbsolutePath().normalize()}")
                 directory.listDirectoryEntries().sorted().forEach {
                     println("${it.toFile().length()}\t${it.normalize()}")
@@ -552,6 +571,51 @@ object SysCalls {
                 }
                 return returnValue(callspec.returns.single(), 30*256 + 80, vm)    // just return some defaults in this case 80*30
             }
+
+            Syscall.CURDIR -> {
+                val curdir = Path("").toAbsolutePath().toString()
+                vm.memory.setString(0xfe00, curdir, true)
+                return returnValue(callspec.returns.single(), 0xfe00, vm)
+            }
+            Syscall.MKDIR -> {
+                val namePtr = getArgValues(callspec.arguments, vm).single() as UShort
+                val name = vm.memory.getString(namePtr.toInt())
+                Path(name).createDirectory()
+            }
+            Syscall.RMDIR -> {
+                val namePtr = getArgValues(callspec.arguments, vm).single() as UShort
+                val name = vm.memory.getString(namePtr.toInt())
+                Path(name).deleteIfExists()
+            }
+            Syscall.CHDIR -> throw NotImplementedError("chdir is not possible in java/kotlin")
+            Syscall.OPEN_FILE -> {
+                val namePtr = getArgValues(callspec.arguments, vm).single() as UShort
+                val name = vm.memory.getString(namePtr.toInt())
+                val success = vm.open_file_read(name)
+                return returnValue(callspec.returns.single(), success, vm)
+            }
+            Syscall.OPEN_FILE_WRITE -> {
+                val namePtr = getArgValues(callspec.arguments, vm).single() as UShort
+                val name = vm.memory.getString(namePtr.toInt())
+                val success = vm.open_file_write(name)
+                return returnValue(callspec.returns.single(), success, vm)
+            }
+            Syscall.READ_FILE_BYTE -> {
+                val (success, byte) = vm.read_file_byte()
+                if(success)
+                    return returnValue(callspec.returns.single(), 0x0100 or byte.toInt(), vm)
+                else
+                    return returnValue(callspec.returns.single(), 0x0000, vm)
+            }
+            Syscall.WRITE_FILE_BYTE -> {
+                val byte = getArgValues(callspec.arguments, vm).single() as UByte
+                if(vm.write_file_byte(byte))
+                    return returnValue(callspec.returns.single(), 1, vm)
+                else
+                    return returnValue(callspec.returns.single(), 0, vm)
+            }
+            Syscall.CLOSE_FILE -> vm.close_file_read()
+            Syscall.CLOSE_FILE_WRITE -> vm.close_file_write()
         }
     }
 }

virtualmachine/src/prog8/vm/VirtualMachine.kt

@@ -6,7 +6,12 @@ import prog8.code.target.virtual.VirtualMachineDefinition
 import prog8.intermediate.*
 import java.awt.Color
 import java.awt.Toolkit
-import kotlin.collections.ArrayDeque
+import java.io.IOException
+import java.io.InputStream
+import java.io.OutputStream
+import kotlin.io.path.Path
+import kotlin.io.path.inputStream
+import kotlin.io.path.outputStream
 import kotlin.math.*
 import kotlin.random.Random
 
@@ -34,6 +39,9 @@ class BreakpointException(val pcChunk: IRCodeChunk, val pcIndex: Int): Exception
 @Suppress("FunctionName")
 class VirtualMachine(irProgram: IRProgram) {
     class CallSiteContext(val returnChunk: IRCodeChunk, val returnIndex: Int, val fcallSpec: FunctionCallArgs)
+
+    private var fileOutputStream: OutputStream? = null
+    private var fileInputStream: InputStream? = null
     val memory = Memory()
     val machinedef = VirtualMachineDefinition()
     val program: List<IRCodeChunk>
@@ -2489,6 +2497,62 @@ class VirtualMachine(irProgram: IRProgram) {
     fun randomSeedFloat(seed: Double) {
         randomGeneratorFloats = Random(seed.toBits())
     }
+
+    fun open_file_read(name: String): Int {
+        try {
+            fileInputStream = Path(name).inputStream()
+        } catch (_: IOException) {
+            return 0
+        }
+        return 1
+    }
+
+    fun open_file_write(name: String): Int {
+        try {
+            fileOutputStream = Path(name).outputStream()
+        } catch (_: IOException) {
+            return 0
+        }
+        return 1
+    }
+
+    fun close_file_read() {
+        fileInputStream?.close()
+        fileInputStream=null
+    }
+
+    fun close_file_write() {
+        fileOutputStream?.flush()
+        fileOutputStream?.close()
+        fileOutputStream=null
+    }
+
+    fun read_file_byte(): Pair<Boolean, UByte> {
+        return if(fileInputStream==null)
+            false to 0u
+        else {
+            try {
+                val byte = fileInputStream!!.read()
+                if(byte>=0)
+                    true to byte.toUByte()
+                else
+                    false to 0u
+            } catch(_: IOException) {
+                false to 0u
+            }
+        }
+    }
+
+    fun write_file_byte(byte: UByte): Boolean {
+        if(fileOutputStream==null)
+            return false
+        try {
+            fileOutputStream!!.write(byte.toInt())
+            return true
+        } catch(_: IOException) {
+            return false
+        }
+    }
 }
 
 internal fun ArrayDeque<UByte>.pushw(value: UShort) {