Add signal() and raise()

git-svn-id: svn://svn.cc65.org/cc65/trunk@2017 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/common/Makefile

@@ -44,8 +44,11 @@ C_OBJS =	_afailed.o	\
 		putchar.o	\
 		puts.o 		\
 		qsort.o		\
+                raise.o         \
 		realloc.o	\
 		rewind.o	\
+                signal.o        \
+                sigtable.o      \
 		sscanf.o	\
                 strftime.o      \
 		strxfrm.o	\

libsrc/common/raise.s

@@ -0,0 +1,44 @@
+;
+; Ullrich von Bassewitz, 2003-03-14
+;
+; int __fastcall__ raise (int sig);
+;
+
+        .import         jmpvec
+
+        .include        "signal.inc"
+
+
+;----------------------------------------------------------------------------
+; int __fastcall__ raise (int sig);
+
+
+_raise:
+        cpx     #0
+        bne     invalidsig
+        cmp     #SIGCOUNT
+        bcs     invalidsig
+
+; Save the signal number low byte, then setup the function vector
+
+        pha
+        asl     a
+        tax
+        lda     sigtable,x
+        sta     jmpvec+1
+        lda     sigtable+1,x
+        sta     jmpvec+2
+
+; Restore the signal number and call the function
+
+        pla                     ; Low byte
+        ldx     #0              ; High byte
+        jsr     jmpvec          ; Call signal function
+
+; raise() returns zero on success and any other value on failure
+
+        lda     #0
+        tax
+invalidsig:
+        rts
+

libsrc/common/signal.s

@@ -0,0 +1,68 @@
+;
+; Ullrich von Bassewitz, 2002-12-16
+;
+; __sigfunc __fastcall__ signal (int sig, __sigfunc func);
+;
+
+	.import		popax
+	.importzp	ptr1
+
+        .include        "signal.inc"
+        .include        "errno.inc"
+
+
+; Default signal functions: The standard specifies explicitly that the values
+; for SIG_IGN and SIG_DFL must be distinct, so we make them so by using both
+; rts exits we have. This works because signal functions are __fastcall__, so
+; we don't have arguments on the stack.
+
+
+;----------------------------------------------------------------------------
+; __sigfunc __fastcall__ signal (int sig, __sigfunc func);
+
+
+_signal:
+        sta     ptr1
+        stx     ptr1+1          ; Remember func
+
+        jsr     popax           ; Get sig
+
+        cpx     #0
+        bne     invalidsig
+        cmp     #SIGCOUNT
+        bcs     invalidsig
+
+; Signal number is valid. Replace the pointer in the table saving the old
+; value temporarily on the stack.
+
+        asl     a               ; Prepare for word access
+        tax
+
+        lda     sigtable,x
+        pha
+        lda     ptr1
+        sta     sigtable,x
+        lda     sigtable+1,x
+        pha
+        lda     ptr1+1
+        sta     sigtable+1,x
+
+; Get the old value from the stack and return it
+
+        pla
+        tax
+        pla
+__sig_ign:
+        rts
+
+; Error entry: We use our knowledge that SIG_ERR is zero here to save a byte
+
+invalidsig:
+        lda     #<EINVAL
+        sta     __errno
+        lda     #>EINVAL        ; A = 0
+        sta     __errno+1
+        tax                     ; A/X = 0
+__sig_dfl:
+        rts
+

libsrc/common/sigtable.s

@@ -0,0 +1,24 @@
+;
+; Ullrich von Bassewitz, 2002-12-16
+;
+; Signal vector table
+;
+
+        .export         sigtable
+
+        .include        "signal.inc"
+
+;----------------------------------------------------------------------------
+;
+
+.data
+
+sigtable:
+        .word   __sig_dfl       ; SIGABRT
+        .word   __sig_dfl       ; SIGFPE
+        .word   __sig_dfl       ; SIGILL
+        .word   __sig_dfl       ; SIGINT
+        .word   __sig_dfl       ; SIGSEGV
+        .word   __sig_dfl       ; SIGTERM
+
+