Add Type and More, and the file stream they are built on

Two applications that read a file too big for Data Memory: Type prints one, More pages it. Both sit on fileStream.asm, which wraps osFileInfo and osFileBlock into open-and-next so an application walks a file's blocks without repeating the service calls. The disk fixture is deliberately awkward: readable.txt crosses several blocks and carries no zero byte to be mistaken for an end marker, and empty.txt says that zero blocks is a valid file rather than an error. These three files were written by ChatGPT, as their headers record. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW
2026-08-24 17:15:53 -04:00
parent 4fd8bf7b3f
commit dbe58db660
10 changed files with 544 additions and 0 deletions
@@ -0,0 +1,151 @@
+; Read a text file one screen at a time.
+;
+; Twenty two lines are shown before a prompt. Space advances another screen, Return one
+; line, and q gives the machine back to CosmOS. This is forward-only on purpose: the file
+; stream holds one block and never asks the whole document to fit in memory.
+;
+; Written by ChatGPT for Anachronaut's SplitBit
+
+#Include services.asm
+#Program
+  #Base 0x2000
+
+start:
+  SETD.0 Name
+  INIB 0d29
+  SWI osArgument
+  SETD.0 Name
+  LDA.0
+  BRA noName
+  CALL fileStreamOpen
+  BNQ openFailed
+  CALL fullPage
+
+nextBlock:
+  CALL fileStreamNext
+  BNQ readFailed
+  PSHD.3
+  POPB
+  POPA
+  SETD.2 Remaining
+  STA.2
+  INCD.2
+  STB.2
+  OR
+  BRQ finished
+  SETD.1 FileStreamBlock
+  SETD.2 Remaining
+
+printLoop:
+  LDA.1
+  OUTA 0x00
+  INIB 0x0A
+  XOR
+  BNQ bytePrinted
+  SETD.3 LinesLeft
+  LDA.3
+  DECA
+  STA.3
+  BNA bytePrinted
+  CALL pause
+  BNQ finished
+bytePrinted:
+  INCD.1
+  CALL fileStreamTakeRemaining
+  BRQ nextBlock
+  BRI printLoop
+
+; Ask for one key without asking for Return. The console is put back immediately,
+; including on q and end of redirected input.
+pause:
+  SETD.0 MorePrompt
+  SWI osPrintString
+  INIA 0x01
+  OUTA 0x02
+  INA 0x00
+  PSHA                      ; Keep the key while A is used to restore line mode.
+  RSTA
+  OUTA 0x02
+  POPA
+  SETD.0 ClearPrompt
+  SWI osPrintString
+
+  INIB 0x71                 ; q
+  XOR
+  BRQ pauseQuit
+  INIB 0xFF                 ; end of redirected input
+  XOR
+  BRQ pauseQuit
+  INIB 0x0A                 ; Return: one more line.
+  XOR
+  BRQ oneLine
+  INIB 0x20                 ; Space: one more screen.
+  XOR
+  BNQ pause                 ; Ignore every other key.
+  CALL fullPage
+  RSTA
+  RSTB
+  OR
+  RET
+oneLine:
+  SETD.3 LinesLeft
+  INIA 0x01
+  STA.3
+  RSTA
+  RSTB
+  OR
+  RET
+pauseQuit:
+  RSTA
+  INIB 0x01
+  OR
+  RET
+fullPage:
+  SETD.3 LinesLeft
+  INIA 0d22
+  STA.3
+  RET
+
+noName:
+  SETD.0 Usage
+  SWI osPrintString
+  SWI osExit
+openFailed:
+  SETD.0 OpenError
+  SWI osPrintString
+  BRI printError
+readFailed:
+  SETD.0 ReadError
+  SWI osPrintString
+printError:
+  RSTA
+  MVQB
+  SWI osPrintNumber
+  SETD.0 NewLine
+  SWI osPrintString
+finished:
+  SWI osExit
+
+#Data
+  #Base 0x1000
+Usage:
+"more: give me a file name
+"
+OpenError:
+"more: cannot find the file, error "
+ReadError:
+"more: cannot read the file, error "
+NewLine:
+  0x0A 0x00
+MorePrompt:
+"-- more --"
+ClearPrompt:
+  0x0A 0x00
+Name:
+  #Reserve 0d29
+Remaining:
+  0x00 0x00
+LinesLeft:
+  0x00
+
+#Include fileStream.asm