WIP: [atari] fgetpos/fsetpos using NOTE/POINT

mos-platform/atari8-common/CMakeLists.txt

@@ -28,15 +28,18 @@ target_link_libraries(atari8-common-crt0 PRIVATE common-asminc)
 add_platform_library(atari8-common-c
   putchar.c
   getchar.c
+  update_diskpos.c
 
   close.s
   fdtab.s
   fdtable.s
   fdtoiocb.s
   findfreeiocb.s
   getfd.s
+  note.s
   open.s
   oserror.s
+  point.s
   rwcommon.s
   sysremove.s
   write.s

mos-platform/atari8-common/note.s

@@ -0,0 +1,42 @@
+; Copyright 2024 LLVM-MOS Project
+; Licensed under the Apache License, Version 2.0 with LLVM Exceptions.
+; See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
+; information.
+
+; char __note (int fd, fpos_t *pos);
+
+        .include "atari.inc"
+        .include "imag.inc"
+
+        .globl  __note
+
+__note:
+        jsr     fdtoiocb
+        bmi     error
+        tax
+        lda     #NOTE
+        sta     ICCOM,x
+        jsr     CIOV
+        bmi     error
+        ldy     #0
+        lda     ICAX5,x
+        sta     (__rc2),y
+        iny
+        lda     ICAX3,x
+        sta     (__rc2),y
+        iny
+        lda     ICAX4,x
+        sta     (__rc2),y
+        iny
+        lda     #0
+        sta     (__rc2),y
+        rts
+
+error:
+        ldy     #3
+        lda     #$ff
+store_error:
+        sta     (__rc2),y
+        dey
+        bpl     store_error
+        rts

mos-platform/atari8-common/point.s

@@ -0,0 +1,42 @@
+; Copyright 2024 LLVM-MOS Project
+; Licensed under the Apache License, Version 2.0 with LLVM Exceptions.
+; See https://github.com/llvm-mos/llvm-mos-sdk/blob/main/LICENSE for license
+; information.
+
+; char __point (int fd, const fpos_t *pos);
+
+        .include "atari.inc"
+        .include "imag.inc"
+
+        .globl  __point
+
+__point:
+        jsr     fdtoiocb
+        bmi     invalid
+        tax
+        ldy     #3
+        lda     (__rc2),y
+        bne     invalid
+        lda     #POINT
+        sta     ICCOM,x
+        dey
+        lda     (__rc2),y
+        sta     ICAX4,x
+        dey
+        lda     (__rc2),y
+        sta     ICAX3,x
+        dey
+        lda     (__rc2),y
+        sta     ICAX5,x
+        jsr     CIOV
+        bmi     cioerr
+        lda     #0
+        rts
+
+invalid:
+        lda     #<EINVAL
+        jmp     __directerrno
+
+cioerr:
+        tya
+        jmp     __mappederrno

mos-platform/atari8-common/update_diskpos.c

@@ -0,0 +1,8 @@
+#include <stdio.h>
+#include <__stdio-internal.h>
+
+char __note(int fd, fpos_t *pos);
+
+void __update_diskpos(FILE *stream) {
+  __note(stream->handle, &stream->diskpos);
+}

mos-platform/common/c/stdio-full.c

@@ -8,12 +8,13 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
-#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 
+#include <__stdio-internal.h>
+
 // Flags for representing mode (see fopen()). Note these must fit the same
 // status field as the _IO?BF flags in <stdio.h> and the internal flags below.
 #define FREAD (1u << 3)
@@ -37,20 +38,6 @@
 // File associated with stream should be remove()d on closing (tmpfile()).
 #define DELONCLOSE (1u << 14)
 
-struct _FILE {
-  signed char handle;   // OS file handle
-  char *buffer;         // Pointer to buffer memory
-  size_t bufsize;       // Size of buffer
-  size_t bufidx;        // Index of current position in buffer
-  size_t bufend;        // Index of last pre-read character in buffer
-  fpos_t pos;           // Offset and multibyte parsing state
-  char ungetc_buf;      // ungetc() buffer
-  bool ungetc_buf_full; // Number of ungetc()'ed characters
-  unsigned status;      // Status flags; see above
-  char *filename;       // Name the current stream has been opened with
-  FILE *next;           // Pointer to next struct (internal)
-};
-
 // Buffer one-two lines; write() implementations have constant overhead, and
 // buffering amortizes it.
 static char serr_buf[80];
@@ -130,6 +117,9 @@ static unsigned filemode(const char *const mode) {
   return rc;
 }
 
+__attribute__((weak)) void __update_diskpos(FILE *stream) {
+}
+
 static FILE *init_file(FILE *stream) {
   FILE *rc = stream;
 
@@ -563,6 +553,8 @@ static int prep_read(FILE *stream) {
 }
 
 static int fill_buffer(FILE *stream) {
+  __update_diskpos(stream);
+
   /* No need to handle buffers > INT_MAX, as PDCLib doesn't allow them */
   int rc = read(stream->handle, stream->buffer, stream->bufsize);
 

mos-platform/common/include/__stdio-internal.h

@@ -0,0 +1,24 @@
+#ifndef __STDIO_INTERNAL_H_
+#define __STDIO_INTERNAL_H_
+
+#include <stdbool.h>
+#include <stdio.h>
+
+struct _FILE {
+  signed char handle;   // OS file handle
+  char *buffer;         // Pointer to buffer memory
+  size_t bufsize;       // Size of buffer
+  size_t bufidx;        // Index of current position in buffer
+  size_t bufend;        // Index of last pre-read character in buffer
+  fpos_t pos;           // Offset and multibyte parsing state
+  char ungetc_buf;      // ungetc() buffer
+  bool ungetc_buf_full; // Number of ungetc()'ed characters
+  unsigned status;      // Status flags; see above
+  char *filename;       // Name the current stream has been opened with
+  fpos_t diskpos;       // Atari NOTE position
+  FILE *next;           // Pointer to next struct (internal)
+};
+
+void __update_diskpos(FILE *stream);
+
+#endif // __STDIO_INTERNAL_H_