small optimization; fix line buffered read of length 0

git-svn-id: svn://svn.cc65.org/cc65/trunk@3065 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/libsrc/atari/read.s b/libsrc/atari/read.s
index b5b6ee0111fcce80a2f8bfff9b30b5dd23a6559c..b7183d12ba2aff155e2cdb7514ec6b2c98d9a03e 100644 (file)
--- a/libsrc/atari/read.s
+++ b/libsrc/atari/read.s
@@ -1,5 +1,5 @@
 ;
-; Christian Groessler, May-2004
+; Christian Groessler, Jun-2004
 ;
 ; int __fastcall__ read(int fd,void *buf,int count)
 ;
@@ -87,7 +87,7 @@ newbuf:
        lda     ICBLL,x         ; get # of bytes read
        sta     buflen
        lda     #0
-       sta     index
+       sta     index           ; fresh buffer
 
        ; restore user buffer address & length
        pla
@@ -103,6 +103,7 @@ newbuf:
        sta     ICBLL,x
 
        ; fall into use_buf
+       lda     buflen
 
 ; return bytes from line buffer
 ; use buflen and index to access buffer
@@ -110,7 +111,6 @@ newbuf:
 ; use dataptr as a temporary pointer
 
 use_buf:
-       lda     buflen
        sec
        sbc     index           ; size of unread data in the buffer
        sta     cbs
@@ -162,9 +162,7 @@ c1: ldx     #0
 btsmall:
        lda     cbs
        sta     ICBLL,x
-       bne     icbll_copy
-
-;      brk                     ; not reached
+       bpl     icbll_copy
 
        .zeropage