Make SpriteExtend perform sanity checks on sprite/area pointers

Detail:
  Sources/SprExtend - Added new CheckAlignedAndSensible macro to make it easy to check pointers. Pointers which aren't word aligned or are less than 256 are considered bad.
  Sources/SprOp - Update findsprite, getspritename and getspriteaddr to check sprite/area/name pointers for validity. Sprite names are the only ones that are allowed to not be word aligned.
Admin:
  Tested on rev A2 BB-xM.


Version 1.43. Tagged as 'SprExtend-1_43'

Sources/SprExtend

@@ -257,6 +257,15 @@ $l      LDR     $temp, [$sprite, #$offset]
         BHI     %F99                    ; out of range
         MEND
 
+        MACRO
+$l      CheckAlignedAndSensible $addr,$failed
+$l      TST     $addr, #3 ; word aligned?
+        BNE     $failed
+        CMP     $addr, #256 ; outside processor vectors?
+        BLO     $failed
+        MEND
+        
+
 ; ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 ; Data areas & register allocation
 ; ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Sources/SprOp

@@ -1042,6 +1042,12 @@ getspritename
 
         ADRL    R3,spritename
         ADD     R4,R3,#12
+
+        CMP     R2,#256                 ; sensible name ptr?
+        BHS     %FT01
+        ADR     R0,ErrorBlock_BadAddress
+        BL      copy_error_one
+        B       %FT99
 01
         LDRB    R0,[R2],#1
         CMP     R0,#" "                 ; ignore control characters and <space> too!
@@ -1076,14 +1082,17 @@ getspriteaddr
         ADREQ   R0, ErrorBlock_NoWorkSpace   ; can't do anything with this!
         addr    r1, Title, EQ
         BLEQ    copy_error_one          ; Always sets the V bit
-        BVS     %FT99
+        BVS     %FT98
 
         MOV     R1,R0                   ; R1 -> system sprite area
         STR     R1,[sp]                 ; return for AppendSprite
+        B       %FT01
 00
+        CheckAlignedAndSensible R1,%F99
         TEQ     R14,#&200               ; R2 --> sprite already
-        BEQ     %FT99
+        BEQ     %FT97
 
+01
         ADRL    R14,spritename
         LDMIA   R14,{R3,R4,R5}
 
@@ -1101,7 +1110,7 @@ getspriteaddr
       ]
 
         BLCS    get_sprite_doesnt_exist_error  ; r0-> error block, V set
-        BVS     %FT99
+        BVS     %FT98
 
         LDMIA   R2,{R1,R6,R7,R8}       ; get link plus name
         TEQ     R6,R3
@@ -1109,9 +1118,17 @@ getspriteaddr
         TEQEQ   R8,R5
         ADDNE   R2,R2,R1
         BNE     %BT04
+97
+        CheckAlignedAndSensible R2,%F99
+98
+        Pull    "R1,R3-R9,PC"
 99
+        ADR     R0,ErrorBlock_BadAddress
+        BL      copy_error_one
         Pull    "R1,R3-R9,PC"
 
+        MakeErrorBlock BadAddress
+        
         ; makepalette16bpp
         ; convert palette to 16bpp for output to 16bpp mode plotting directly from palette
         ; if this is not done, the spriteextend blitter will run out of registers!
@@ -2889,8 +2906,7 @@ Go_CheckSpriteArea
 
         Push    "r1-r5, lr"             ; 6 regs + r0/r10/r11 to mess with, total 9
 
-        TST     r1, #3                  ; at least need an aligned area to start with
-        BNE     %FT99
+        CheckAlignedAndSensible r1,%F99 ; at least need an aligned area to start with
         
         ASSERT  SpriteAreaCBsize = (4 * 4)
         LDMIA   r1, {r2-r5}

VersionASM

@@ -11,13 +11,13 @@
                         GBLS    Module_HelpVersion
                         GBLS    Module_ComponentName
                         GBLS    Module_ComponentPath
-Module_MajorVersion     SETS    "1.42"
-Module_Version          SETA    142
+Module_MajorVersion     SETS    "1.43"
+Module_Version          SETA    143
 Module_MinorVersion     SETS    ""
-Module_Date             SETS    "14 Apr 2011"
-Module_ApplicationDate  SETS    "14-Apr-11"
+Module_Date             SETS    "25 Jun 2011"
+Module_ApplicationDate  SETS    "25-Jun-11"
 Module_ComponentName    SETS    "SprExtend"
 Module_ComponentPath    SETS    "mixed/RiscOS/Sources/Video/Render/SprExtend"
-Module_FullVersion      SETS    "1.42"
-Module_HelpVersion      SETS    "1.42 (14 Apr 2011)"
+Module_FullVersion      SETS    "1.43"
+Module_HelpVersion      SETS    "1.43 (25 Jun 2011)"
                         END

VersionNum

-/* (1.42)
+/* (1.43)
  *
  * This file is automatically maintained by srccommit, do not edit manually.
  * Last processed by srccommit version: 1.1.
  *
  */
-#define Module_MajorVersion_CMHG        1.42
+#define Module_MajorVersion_CMHG        1.43
 #define Module_MinorVersion_CMHG        
-#define Module_Date_CMHG                14 Apr 2011
+#define Module_Date_CMHG                25 Jun 2011
 
-#define Module_MajorVersion             "1.42"
-#define Module_Version                  142
+#define Module_MajorVersion             "1.43"
+#define Module_Version                  143
 #define Module_MinorVersion             ""
-#define Module_Date                     "14 Apr 2011"
+#define Module_Date                     "25 Jun 2011"
 
-#define Module_ApplicationDate          "14-Apr-11"
+#define Module_ApplicationDate          "25-Jun-11"
 
 #define Module_ComponentName            "SprExtend"
 #define Module_ComponentPath            "mixed/RiscOS/Sources/Video/Render/SprExtend"
 
-#define Module_FullVersion              "1.42"
-#define Module_HelpVersion              "1.42 (14 Apr 2011)"
-#define Module_LibraryVersionInfo       "1:42"
+#define Module_FullVersion              "1.43"
+#define Module_HelpVersion              "1.43 (25 Jun 2011)"
+#define Module_LibraryVersionInfo       "1:43"