Added secondary linker config for C64 overlays (incl. demo program).

git-svn-id: svn://svn.cc65.org/cc65/trunk@5679 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/samples/Makefile b/samples/Makefile
index a5bf9acefe3ae8fe2697176a87194c43e3e26a55..746de79a7320098641b94913c4350a2d08af197b 100644 (file)
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -122,6 +122,9 @@ endif
 
 nachtm:                nachtm.o
 
+overlaydemo:   overlaydemo.o
+       @$(LD) -t $(SYS) -m $(basename $@).map -C $(SYS)-overlay.cfg -o $@ $^ $(CLIB)
+
 plasma:                plasma.o
 
 sieve:         sieve.o

diff --git a/samples/overlaydemo.c b/samples/overlaydemo.c
new file mode 100644 (file)
index 0000000..02451a2
--- /dev/null
+++ b/samples/overlaydemo.c
@@ -0,0 +1,86 @@
+/*
+ * Minimalistic overlay demo program.
+ *
+ * 2009-10-02, Oliver Schmidt (ol.sc@web.de)
+ *
+ */
+
+
+
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+
+extern void _OVERLAY1_LOAD__, _OVERLAY1_SIZE__;
+extern void _OVERLAY2_LOAD__, _OVERLAY2_SIZE__;
+extern void _OVERLAY3_LOAD__, _OVERLAY3_SIZE__;
+
+
+void log (char *msg)
+{
+    printf ("Log: %s\n", msg);
+}
+
+
+#pragma code-name (push, "OVERLAY1");
+
+void foo (void)
+{
+    log ("Calling main from overlay 1");
+}
+
+#pragma code-name (pop);
+
+
+#pragma code-name (push, "OVERLAY2");
+
+void bar (void)
+{
+    log ("Calling main from overlay 2");
+}
+
+#pragma code-name (pop);
+
+
+#pragma code-name (push, "OVERLAY3");
+
+void foobar (void)
+{
+    log ("Calling main from overlay 3");
+}
+
+#pragma code-name(pop);
+
+
+unsigned char loadfile (char *name, void *addr, void *size)
+{
+    int file = open (name, O_RDONLY);
+    if (file == -1) {
+        log ("Opening overlay file failed");
+        return 0;
+    }
+
+    read (file, addr, (unsigned) size);
+    close (file);
+    return 1;
+}
+
+
+void main (void)
+{
+    log ("Calling overlay 1 from main");
+    if (loadfile ("overlaydemo.1", &_OVERLAY1_LOAD__, &_OVERLAY1_SIZE__)) {
+        foo ();
+    }
+
+    log ("Calling overlay 2 from main");
+    if (loadfile ("overlaydemo.2", &_OVERLAY2_LOAD__, &_OVERLAY2_SIZE__)) {
+        bar ();
+    }
+
+    log ("Calling overlay 3 from main");
+    if (loadfile ("overlaydemo.3", &_OVERLAY3_LOAD__, &_OVERLAY3_SIZE__)) {
+        foobar ();
+    }
+}

diff --git a/src/ld65/cfg/c64-overlay.cfg b/src/ld65/cfg/c64-overlay.cfg
new file mode 100644 (file)
index 0000000..5995ce2
--- /dev/null
+++ b/src/ld65/cfg/c64-overlay.cfg
@@ -0,0 +1,57 @@
+SYMBOLS {
+    __LOADADDR__:    type = import;
+    __EXEHDR__:      type = import;
+    __STACKSIZE__:   type = weak, value = $0800; # 2k stack
+    __OVERLAYSIZE__: type = weak, value = $1000; # 4k overlay
+}
+MEMORY {
+    ZP:       file = "", define = yes, start = $0002,                   size = $001A;
+    LOADADDR: file = %O,               start = $07FF,                   size = $0002;
+    HEADER:   file = %O,               start = $0801,                   size = $000C;
+    RAM:      file = %O, define = yes, start = $080D,                   size = $C7F3 - __OVERLAYSIZE__ - __STACKSIZE__;
+    OVL1:     file = "%O.1",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL2:     file = "%O.2",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL3:     file = "%O.3",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL4:     file = "%O.4",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL5:     file = "%O.5",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL6:     file = "%O.6",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL7:     file = "%O.7",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL8:     file = "%O.8",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+    OVL9:     file = "%O.9",           start = $D000 - __OVERLAYSIZE__, size = __OVERLAYSIZE__;
+}
+SEGMENTS {
+    LOADADDR: load = LOADADDR, type = ro;
+    EXEHDR:   load = HEADER,   type = ro;
+    STARTUP:  load = RAM,      type = ro;
+    LOWCODE:  load = RAM,      type = ro,                optional = yes;
+    INIT:     load = RAM,      type = ro,  define = yes, optional = yes;
+    CODE:     load = RAM,      type = ro;
+    RODATA:   load = RAM,      type = ro;
+    DATA:     load = RAM,      type = rw;
+    ZPSAVE:   load = RAM,      type = bss;
+    BSS:      load = RAM,      type = bss, define = yes;
+    ZEROPAGE: load = ZP,       type = zp;
+    OVERLAY1: load = OVL1,     type = ro,  define = yes, optional = yes;
+    OVERLAY2: load = OVL2,     type = ro,  define = yes, optional = yes;
+    OVERLAY3: load = OVL3,     type = ro,  define = yes, optional = yes;
+    OVERLAY4: load = OVL4,     type = ro,  define = yes, optional = yes;
+    OVERLAY5: load = OVL5,     type = ro,  define = yes, optional = yes;
+    OVERLAY6: load = OVL6,     type = ro,  define = yes, optional = yes;
+    OVERLAY7: load = OVL7,     type = ro,  define = yes, optional = yes;
+    OVERLAY8: load = OVL8,     type = ro,  define = yes, optional = yes;
+    OVERLAY9: load = OVL9,     type = ro,  define = yes, optional = yes;
+}
+FEATURES {
+    CONDES: segment = INIT,
+           type    = constructor,
+           label   = __CONSTRUCTOR_TABLE__,
+           count   = __CONSTRUCTOR_COUNT__;
+    CONDES: segment = RODATA,
+           type    = destructor,
+           label   = __DESTRUCTOR_TABLE__,
+           count   = __DESTRUCTOR_COUNT__;
+    CONDES: segment = RODATA,
+           type    = interruptor,
+           label   = __INTERRUPTOR_TABLE__,
+           count   = __INTERRUPTOR_COUNT__;
+}