Fix read bugs

1 files changed, 110 insertions, 74 deletions

diff --git a/read.s b/read.s
index 9b4e382..ad07fd0 100644
--- a/read.s
+++ b/read.s
@@ -2,100 +2,136 @@ read:
 002000 012705 MOV #7000, R5     ; move read buffer address into R5
 002002 007000
 002004 105025 CLRB (R5)+        ; move null byte into buffer
-loop:
-002006 032737 BIT #000200, @#177560
+get:
+002006 032737 BIT #200, @#177560
 002010 000200
 002012 177560
-002014 001774 BEQ loop          ; loop until char ready
+002014 001774 BEQ get           ; loop until char ready
 002016 113701 MOVB @#177562, R1
-002020 120127 CMPB R1, "\n"     ; done if enter was pressed
-002022 000012
-002024 001422 BEQ done
-002026 120127 CMPB R1, " "      ; good if space
-002030 000040
-002032 001414 BEQ good
-002034 120127 CMPB R1, "("      ; good if left paren
-002036 000050
-002040 001411 BEQ good
-002042 120127 CMPB R1, ")"      ; good if right paren
-002044 000051
-002046 001406 BEQ good
-002050 120127 CMPB R1, "A"      ; bad if lower than A
-002052 000101
-002054 103405 BLO bad
-002056 120127 CMPB R1, "Z"      ; bad if higher than Z
-002060 000132
-002062 101002 BHI bad
+002020 177562
+002022 120127 CMPB R1, "\r"     ; done if enter was pressed
+002024 000015
+002026 001430 BEQ done
+002030 120127 CMPB R1, " "      ; good if space
+002032 000040
+002034 001414 BEQ good
+002036 120127 CMPB R1, "("      ; good if left paren
+002040 000050
+002042 001411 BEQ good
+002044 120127 CMPB R1, ")"      ; good if right paren
+002046 000051
+002050 001406 BEQ good
+002052 120127 CMPB R1, "A"      ; bad if lower than A
+002054 000101
+002056 103413 BLO bad
+002060 120127 CMPB R1, "Z"      ; bad if higher than Z
+002062 000132
+002064 101010 BHI bad
 good:
-002064 110125 MOVB R1, (R5)+    ; move good char into buffer
-002066 000747 BR loop           ; keep getting chars
+002066 110125 MOVB R1, (R5)+    ; move good char into buffer
+echo:
+; echo good char
+002070 032737 BIT #200, @#177654
+002072 000200
+002074 177564
+002076 001774 BEQ echo
+002100 110137 MOVB R1, @#177566
+002102 177566
+002104 000740 BR get            ; keep getting chars
 bad:
-002070 000777 BR -2             ; infinite loop
+002106 000737 BR get            ; ignore bad chars
 done:
-002072 000137 JMP #parse_sexp
-002074 002100
+; send carriage return
+002110 032737 BIT #200, @#177654
+002112 000200
+002114 177564
+002116 001774 BEQ done
+002120 112737 MOV "\r", @#177566
+002122 000015
+002124 177566
+; send line feed
+line:
+002126 032737 BIT #200, @#177654
+002130 000200
+002132 177564
+002134 001774 BEQ line
+002136 112737 MOV "\n", @#177566
+002140 000012
+002142 177566
+002144 000137 JMP #parse_sexp
+002146 002200
+
 
 ; R4 = sexps
 parse_sexp:
-002100 004737 JSR PC, #get_next       ; get a character
-002102 002300
-002104 120027 CMPB R0, ")"
-002106 000051
-002110 001020 BNE if_atom             ; if atom get the atom
+002200 004737 JSR PC, #get_next       ; get a character
+002202 002400
+002204 120027 CMPB R0, ")"
+002206 000051
+002210 001022 BNE if_atom             ; if atom get the atom
 ; otherwise (if list)
 ; get the list
 if_list:
-002112 012704 MOV "NIL", R4           ; sexps <- empty list
-002114 005000
+002212 012704 MOV "NIL", R4           ; sexps <- empty list
+002214 005000
 loop:
-002116 004737 JSR PC, #get_next
-002120 002300
-002122 120027 CMPB R0, "("
-002124 000050
-002126 001407 BEQ done                ; if "(" return the accumulated list
+002216 004737 JSR PC, #get_next
+002220 002400
+002222 120027 CMPB R0, "("
+002224 000050
+002226 001411 BEQ done                ; if "(" return the accumulated list
 ; if anything else:
-002130 010446 MOV R4, -(SP)           ; push sexps
-002132 004737 JSR PC, #parse_sexp     ; arg1 <- parse sexp
-002134 012601 MOV (SP)+, R1           ; arg2 <- pop accum
-002136 004737 JSR PC, #cons           ; cons result onto accum
-002140 004400
-002142 010004 MOV R0, R4              ; sexps <- result
-002144 000764 BR loop                 ; continue recognizing list
+002230 110025 MOVB R0, (R5)+          ; put back the char
+002232 010446 MOV R4, -(SP)           ; push sexps
+002234 004737 JSR PC, #parse_sexp     ; arg1 <- parse sexp
+002236 002200
+002240 012601 MOV (SP)+, R1           ; arg2 <- pop accum
+002142 004737 JSR PC, #cons           ; cons result onto accum
+002244 004400
+002246 010004 MOV R0, R4              ; sexps <- result
+002250 000762 BR loop                 ; continue recognizing list
 done:
-002146 010400 MOV R4, R0              ; result <- sexps
-002150 000207 RTS PC
+002252 010400 MOV R4, R0              ; result <- sexps
+002254 000207 RTS PC
 if_atom:
-002152 105046 CLRB -(SP)    ; push null byte to stack
+002256 105046 CLRB -(SP)    ; push null byte to stack
 loop:
-002154 110046 MOVB R0, -(SP)      ; push character to stack
-002156 114500 MOVB -(R5), R0      ; get another character
-002160 120027 CMPB R0, "A"        ;
-002162 000101
-002164 103404 BLO done            ; done if lower than A
-002166 120027 CMPB R0, "Z"        ;
-002170 000132
-002172 101001 BHI done            ; done if higher than Z
-002174 000767 BR loop             ; continue getting characters
+002260 110046 MOVB R0, -(SP)      ; push character to stack
+002262 114500 MOVB -(R5), R0      ; get another character
+002264 120027 CMPB R0, "A"        ;
+002266 000101
+002270 103404 BLO done            ; done if lower than A
+002272 120027 CMPB R0, "Z"        ;
+002274 000132
+002276 101001 BHI done            ; done if higher than Z
+002300 000767 BR loop             ; continue getting characters
 done:
-002176 110026 MOVB R0, (R5)+      ; put the non-letter back
-002200 013702 MOV @#10000, R2     ; get free pointer
-002202 010200 MOV R2, R0          ; result <- address of new atom
-002204 016222 MOV 3(R2), (R2)+    ; allocate atom tag and increment free pointer
-002206 000003
+002302 110025 MOVB R0, (R5)+      ; put the non-letter back
+002304 013702 MOV @#10000, R2     ; get free pointer
+002306 010000
+002310 010200 MOV R2, R0          ; result <- address of new atom
+002312 010203 MOV R2, R3
+002314 062703 ADD #3, R3
+002316 000003
+002320 010322 MOV R3, (R2)+       ; allocate atom tag and increment free pointer
 loop:
-002210 112622 MOVB (SP)+, (R2)+   ; pop a char off the stack and into the heap
+002322 112622 MOVB (SP)+, (R2)+   ; pop a char off the stack and into the heap
                                   ; increment the free pointer (by 1)
-002212 001376 BNE loop            ; if it wasn't null keep going
-002214 005722 TST (R2)+           ; align free pointer
-002216 010237 MOV R2, @#10000     ; store new free pointer
-002230 000207 RTS PC
+002324 001376 BNE loop            ; if it wasn't null keep going
+002326 005202 INC R2              ; align free pointer
+002330 042702 BIC #1, R2
+002332 000001
+002334 010237 MOV R2, @#10000     ; store new free pointer
+002336 010000
+002340 000207 RTS PC
+
 get_next:
 loop:
-002300 114500 MOVB -(R5), R0
-002302 001404 BEQ bad             ; if null byte, no more input, very bad
-002304 120027 CMPB R0, " "        ; check if space
-002306 000040
-002310 001773 BEQ loop            ; skip space
-002312 000207 RTS PC              ; return the lexically-valid character
+002400 114500 MOVB -(R5), R0
+002402 001404 BEQ bad             ; if null byte, no more input, very bad
+002404 120027 CMPB R0, " "        ; check if space
+002406 000040
+002410 001773 BEQ loop            ; skip space
+002412 000207 RTS PC              ; return the lexically-valid character
 bad:
-002314 000777 BR -2               ; infinite loop
+002414 000777 BR -2               ; infinite loop