From 093c04cab71fb928aedf9ea2438d32b326fcb15c Mon Sep 17 00:00:00 2001
From: Peter Ferrie <peter.ferrie@gmail.com>
Date: Sat, 23 Oct 2021 20:53:24 -0700
Subject: [PATCH] add LoadAuxIndexedFile

---
 src/glue.prorwts2.a   | 28 ++++++++++++++++++++++++++++
 src/prodos.impl.lc2.a |  1 +
 2 files changed, 29 insertions(+)

diff --git a/src/glue.prorwts2.a b/src/glue.prorwts2.a
index 37458c467..670c21fc8 100644
--- a/src/glue.prorwts2.a
+++ b/src/glue.prorwts2.a
@@ -128,6 +128,28 @@ LoadDHRFile
          jmp   SwitchToBank1
 
 ;------------------------------------------------------------------------------
+; LoadAuxIndexedFile
+; Load a file from inside an indexed file, all at once into auxiliary memory
+;
+; To save disk space, some collections of small, related files (e.g. per-game
+; help files) are merged into a single data file with an associated index file.
+; The index stores the original filename along with an offset (into the merged
+; data file) and a length.
+;
+; Callers are responsible for loading the index file and finding the relevant
+; record within the index. Most callers use okvs_find() for this.
+;
+; in:    stack contains 6 bytes of parameters:
+;          +1 [word] pointer to filename of merged data file
+;          +3 [word] address of load destination
+;          +5 [word] pointer to index record (see note)
+; out:   all flags clobbered
+;        all registers clobbered
+;------------------------------------------------------------------------------
+LoadAuxIndexedFile
+         lda   #$E8                  ; INX
+         +HIDE_NEXT_2_BYTES
+;------------------------------------------------------------------------------
 ; LoadIndexedFile
 ; Load a file from inside an indexed file, all at once
 ;
@@ -147,6 +169,8 @@ LoadDHRFile
 ;        all registers clobbered
 ;------------------------------------------------------------------------------
 LoadIndexedFile
+         lda   #$EA                  ; NOP
+         sta   @iauxreq
          +PARAMS_ON_STACK 6
          jsr   @set_nameaddr
          +LDPARAMPTR 5, zpword
@@ -172,6 +196,10 @@ LoadIndexedFile
          jsr   $bf00
          !byte $ce
          !word @ce_parms
+@iauxreq
+         nop                         ; SMC
+         stx SavedZP + auxreq - first_zp
+
          jsr   $bf00
          !byte $ca
          !word @ca_parms
diff --git a/src/prodos.impl.lc2.a b/src/prodos.impl.lc2.a
index fc7a1dbba..f5e602ebb 100644
--- a/src/prodos.impl.lc2.a
+++ b/src/prodos.impl.lc2.a
@@ -21,6 +21,7 @@ buffer = first_zp+2 ;word
 ProDOS_enter
 !set CloseHandles = @imp_close
 !set swap_zpg = @swap_zp
+!set SavedZP = @saved_zp
          stx   ProDOS_savedX+1
          sty   ProDOS_savedY+1
          jsr   @swap_zp