C source code changes so the kernel can compile with ia16-elf-gcc.

Use "make all COMPILER=gcc".
Linking does not work yet with these changes.

hdr/nls.h

@@ -403,7 +403,7 @@ struct nlsExtCntryInfo {
                                    0: 12 hours (append AM/PM)
                                    1: 24 houres
                                  */
-    VOID(FAR * upCaseFct) (VOID);       /* far call to a function upcasing the
+  intvec upCaseFct;             /* far call to a function upcasing the
                                            character in register AL */
   char dataSep[2];              /* ASCIZ of separator in data records */
 };
@@ -474,9 +474,19 @@ struct nlsInfoBlock {           /* This block contains all information
                                    maybe tweaked by NLSFUNC */
   UWORD sysCodePage;            /* system code page */
   unsigned flags;               /* implementation flags */
+#ifdef __GNUC__
+  /* need to initialize using explicit segment/offset */
+  union {
+    struct { struct nlsPackage *off; char *seg; };
+    struct nlsPackage FAR *p;
+  } actPkg, chain;
+  #define actPkg actPkg.p
+  #define chain chain.p
+#else
   struct nlsPackage FAR *actPkg;        /* current NLS package */
   struct nlsPackage FAR *chain; /* first item of info chain --
                                    hardcoded U.S.A./CP437 */
+#endif
 };
 
 extern struct nlsInfoBlock ASM nlsInfo;

hdr/portab.h

@@ -140,8 +140,34 @@ unsigned short getSS(void);
 #define MC68K
 
 #elif defined(__GNUC__)
+
+#ifdef __FAR
+#define I86
+#define far __far
+#define CDECL
+#define VA_CDECL
+#define PASCAL
+
+#define _CS getCS()
+static inline unsigned short getCS(void)
+{
+  unsigned short ret;
+  asm volatile("mov %%cs, %0" : "=r"(ret));
+  return ret;
+}
+
+#define _SS getSS()
+static inline unsigned short getSS(void)
+{
+  unsigned short ret;
+  asm volatile("mov %%ss, %0" : "=r"(ret));
+  return ret;
+}
+extern char DosDataSeg[];
+#else
 /* for warnings only ! */
 #define MC68K
+#endif
 
 #else
 #error Unknown compiler
@@ -313,7 +339,11 @@ typedef signed long LONG;
 #define FP_OFF(fp)             ((size_t)(fp))
 #endif
 
+#if defined(__GNUC__) && defined(__FAR)
+typedef VOID FAR *intvec;
+#else
 typedef VOID (FAR ASMCFUNC * intvec) (void);
+#endif
 
 #define MK_PTR(type,seg,ofs) ((type FAR*) MK_FP (seg, ofs))
 #if __TURBOC__ > 0x202

hdr/process.h

@@ -67,7 +67,7 @@ typedef struct {
      for compatiblity with CP/M apps that do a near call to psp:5
      and expect size (KB) of allocated segment in word at offset 6 */
   UBYTE ps_farcall;             /* 05  far call opcode             */
-  VOID(FAR ASMCFUNC * ps_reentry) (void);  /* 06  re-entry point          */
+  intvec ps_reentry;            /* 06  re-entry point              */
 
   intvec ps_isv22,              /* 0a terminate address            */
          ps_isv23,              /* 0e ctrl-break address           */

kernel/chario.c

@@ -149,6 +149,8 @@ STATIC void fast_put_char(unsigned char chr)
 #if defined(__TURBOC__)
     _AL = chr;
     __int__(0x29);
+#elif defined(__GNUC__)
+    asm volatile("int $0x29":: "a"(chr):"bx");
 #elif defined(I86)
     asm
     {

kernel/fattab.c

@@ -226,7 +226,7 @@ CLUSTER link_fat(struct dpb FAR * dpbp, CLUSTER Cluster1,
 
   if (ISFAT12(dpbp))
   {
-    REG UBYTE FAR *fbp0, FAR * fbp1;
+    REG UBYTE FAR *fbp0; REG UBYTE FAR * fbp1;
     struct buffer FAR * bp1;
     unsigned cluster, cluster2;
 

kernel/globals.h

@@ -156,18 +156,17 @@ typedef BYTE *UPMAP;
 /*                                                                      */
 /* External Assembly variables                                          */
 /*                                                                      */
-extern struct dhdr
+extern struct dhdr FAR ASM clk_dev; /* Clock device driver                  */
-FAR ASM clk_dev,                    /* Clock device driver                  */
+extern struct dhdr FAR ASM con_dev; /* Console device driver                */
-  FAR ASM con_dev,                  /* Console device driver                */
+extern struct dhdr FAR ASM prn_dev; /* Generic printer device driver        */
-  FAR ASM prn_dev,                  /* Generic printer device driver        */
+extern struct dhdr FAR ASM aux_dev; /* Generic aux device driver            */
-  FAR ASM aux_dev,                  /* Generic aux device driver            */
+extern struct dhdr FAR ASM blk_dev; /* Block device (Disk) driver           */
-  FAR ASM blk_dev;                  /* Block device (Disk) driver           */
 extern COUNT *error_tos,        /* error stack                          */
   disk_api_tos,                 /* API handler stack - disk fns         */
   char_api_tos;                 /* API handler stack - char fns         */
-extern BYTE FAR _HMATextAvailable,      /* first byte of available CODE area    */
+extern BYTE FAR _HMATextAvailable;  /* first byte of available CODE area    */
-  FAR _HMATextStart[],          /* first byte of HMAable CODE area      */
+extern BYTE FAR _HMATextStart[];    /* first byte of HMAable CODE area      */
-  FAR _HMATextEnd[];            /* and the last byte of it              */
+extern BYTE FAR _HMATextEnd[];      /* and the last byte of it              */
 extern
 BYTE DosLoadedInHMA;            /* if InitHMA has moved DOS up          */
 
@@ -236,9 +235,8 @@ extern UWORD ASM first_mcb,         /* Start of user memory                 */
   ASM uppermem_root;                /* Start of umb chain (usually 9fff)    */
 extern char * ASM inputptr;         /* pointer to unread CON input          */ 
 extern sfttbl FAR * ASM sfthead;    /* System File Table head               */
-extern struct dhdr
+extern struct dhdr FAR * ASM clock; /* CLOCK$ device                        */
-FAR * ASM clock,                    /* CLOCK$ device                        */
+extern struct dhdr FAR * ASM syscon;/* console device                       */
-  FAR * ASM syscon;                 /* console device                       */
 extern WORD ASM maxsecsize;         /* largest sector size in use (can use) */
 extern struct buffer
 FAR *ASM firstbuf;                  /* head of buffers linked list          */

kernel/init-dat.h

@@ -23,7 +23,7 @@ extern __segment DosTextSeg;
 #define DOSFAR FAR
 #define DOSTEXTFAR FAR
 
-#elif !defined(I86)
+#elif !defined(I86) || defined(__GNUC__)
 
 #define DOSFAR
 #define DOSTEXTFAR

kernel/init-mod.h

@@ -242,7 +242,11 @@ extern void Init_clk_driver(void);
 extern UWORD HMAFree;            /* first byte in HMA not yet used      */
 
 extern unsigned CurrentKernelSegment;
+#ifdef __GNUC__
+extern struct _KernelConfig ASM LowKernelConfig;
+#else
 extern struct _KernelConfig FAR ASM LowKernelConfig;
+#endif
 extern WORD days[2][13];
 extern BYTE FAR *lpTop;
 extern BYTE ASM _ib_start[], ASM _ib_end[], ASM _init_end[];
@@ -256,11 +260,21 @@ extern struct lol FAR *LoL;
 extern struct dhdr DOSTEXTFAR ASM blk_dev; /* Block device (Disk) driver           */
 
 extern struct buffer FAR *DOSFAR firstAvailableBuf; /* first 'available' buffer   */
+#ifdef __GNUC__
+extern struct lol ASM DATASTART;
+#else
 extern struct lol ASM FAR DATASTART;
+#endif
 
-extern BYTE DOSFAR ASM _HMATextAvailable,    /* first byte of available CODE area    */
+extern BYTE DOSFAR ASM _HMATextAvailable;    /* first byte of available CODE area    */
-  FAR ASM _HMATextStart[],          /* first byte of HMAable CODE area      */
+#ifdef __GNUC__
-  FAR ASM _HMATextEnd[], DOSFAR ASM break_ena;  /* break enabled flag                   */
+extern BYTE ASM _HMATextStart[];          /* first byte of HMAable CODE area      */
+extern BYTE ASM _HMATextEnd[];
+#else
+extern BYTE FAR ASM _HMATextStart[];          /* first byte of HMAable CODE area      */
+extern BYTE FAR ASM _HMATextEnd[];
+#endif
+extern BYTE DOSFAR ASM break_ena;  /* break enabled flag                   */
 extern BYTE DOSFAR ASM _InitTextStart[],     /* first available byte of ram          */
   DOSFAR ASM _InitTextEnd[],
   DOSFAR ASM ReturnAnyDosVersionExpected,

kernel/inithma.c

@@ -352,7 +352,8 @@ void MoveKernel(unsigned NewKernelSegment)
        style table
      */
 
-    struct RelocationTable FAR *rp, rtemp;
+    struct RelocationTable FAR *rp;
+    struct RelocationTable rtemp;
 
     /* verify, that all entries are valid */
 

kernel/main.c

@@ -68,7 +68,12 @@ __segment DosTextSeg = 0;
 
 #endif
 
-struct lol FAR *LoL = &DATASTART;
+struct lol FAR *LoL
+#ifndef __GNUC__
+/* cannot initialize from far data with GCC */
+= &DATASTART;
+#endif
+;
 
 VOID ASMCFUNC FreeDOSmain(void)
 {
@@ -90,6 +95,9 @@ VOID ASMCFUNC FreeDOSmain(void)
                             at 50:e0
                         */
 
+#ifdef __GNUC__
+  LoL = &DATASTART;
+#endif
   drv = LoL->BootDrive + 1;
   p = MK_FP(0, 0x5e0);
   if (fmemcmp(p+2,"CONFIG",6) == 0)      /* UPX */
@@ -775,8 +783,12 @@ STATIC void CheckContinueBootFromHarddisk(void)
   init_call_intr(0x13, &r);
 
   {
+#if __GNUC__
+    asm volatile("jmp $0,$0x7c00");
+#else
     void (far *reboot)(void) = (void (far*)(void)) MK_FP(0x0,0x7c00);
 
     (*reboot)();
+#endif
   }
 }

kernel/memmgr.c

@@ -316,7 +316,7 @@ COUNT DosMemFree(UWORD para)
  */
 COUNT DosMemChange(UWORD para, UWORD size, UWORD * maxSize)
 {
-  REG mcb FAR *p, FAR * q;
+  REG mcb FAR *p; mcb FAR * q;
 
   /* Initialize                                                   */
   p = para2far(para - 1);       /* pointer to MCB */

kernel/nls.c

@@ -66,8 +66,13 @@ struct nlsInfoBlock ASM nlsInfo = {
 #ifdef NLS_REORDER_POINTERS
       | NLS_CODE_REORDER_POINTERS
 #endif
+#ifdef __GNUC__
+      , {.seg=DosDataSeg, .off=&nlsPackageHardcoded} /* hardcoded first package */
+      , {.seg=DosDataSeg, .off=&nlsPackageHardcoded} /* first item in chain */
+#else
       , &nlsPackageHardcoded    /* hardcoded first package */
       , &nlsPackageHardcoded    /* first item in chain */
+#endif
 };
 
         /* getTableX return the pointer to the X'th table; X==subfct */

kernel/prf.c

@@ -29,7 +29,11 @@
 #include "portab.h"
 
 #ifdef FORSYS
+#ifdef __GNUC__
+#include <unistd.h>
+#else
 #include <io.h>
+#endif
 #include <stdarg.h>
 #endif
 
@@ -105,6 +109,8 @@ void put_console(int c)
   __int__(0x29);
 #elif defined(__WATCOMC__)
   int29(c);
+#elif defined(__GNUC__)
+  asm volatile("int $0x29" : : "a"(c) : "bx");
 #elif defined(I86)
   __asm
   {
@@ -227,7 +233,8 @@ int VA_CDECL sprintf(char * buff, CONST char * fmt, ...)
 STATIC void do_printf(CONST BYTE * fmt, va_list arg)
 {
   int base;
-  BYTE s[11], FAR * p;
+  BYTE s[11];
+  BYTE FAR * p;
   int size;
   unsigned char flags;
 

kernel/task.c

@@ -509,7 +509,7 @@ COUNT DosComLoader(BYTE FAR * namep, exec_blk * exp, COUNT mode, COUNT fd)
 
 VOID return_user(void)
 {
-  psp FAR *p, FAR * q;
+  psp FAR *p; psp FAR * q;
   REG COUNT i;
   iregs FAR *irp;
 /*  long j;*/

mkfiles/gcc.mak

@@ -0,0 +1,50 @@
+#
+# GCC.MAK - kernel compiler options for ia16-elf-gcc
+#
+
+CC=ia16-elf-gcc -c
+CL=echo ia16-elf-gcc
+INCLUDEPATH=.
+
+!if $(XCPU) != 186
+!if $(XCPU) != 386
+TARGETOPT=-march=i8086
+!endif
+!endif
+
+LIBUTIL=wlib -q
+LIBPLUS=
+LIBTERM=
+
+TINY=-mcmodel=tiny
+CFLAGST=-w -o $@
+CFLAGSC=
+
+TARGET=KGC
+
+#
+# heavy stuff - building  
+#
+# -mcmodel=small small memory model (small code/small data)
+# -fleading-underscore underscores leading field for DOS compiler compat
+# -fno-common    no "common" variables, just BSS for uninitialized data
+# -fpack-struct pack structure members
+# -ffreestanding don't assume any headers
+# -fcall-used-es es clobbered in function calls
+# -mrtd         use stdcall calling convention
+# -w            disable warnings for now
+# -Werror       treat all warnings as errors
+
+ALLCFLAGS=-I../hdr $(TARGETOPT) $(ALLCFLAGS) -mcmodel=small -fleading-underscore -fno-common -fpack-struct -ffreestanding -fcall-used-es -mrtd -w -Werror
+INITCFLAGS=$(ALLCFLAGS) -o $@
+CFLAGS=$(ALLCFLAGS) -o $@
+
+DIRSEP=/
+RM=rm -f
+CP=echo cp
+ECHOTO=echo>>
+INITPATCH=@echo > /dev/null
+CLDEF=1
+CLT=gcc -DDOSC_TIME_H -I../hdr -o $@
+CLC=$(CLT)
+XLINK=echo $(XLINK) debug all op symfile format dos option map,statics,verbose F { $(OBJS) } L ../lib/device.lib N kernel.exe $#

sys/fdkrncfg.c

@@ -19,7 +19,9 @@ char KERNEL[] = "KERNEL.SYS";
 
 #include <stdlib.h>
 #include <string.h>
+#ifndef __GNUC__
 #include <fcntl.h>
+#endif
 
 #include "portab.h"
 /* These definitions deliberately put here instead of
@@ -29,7 +31,7 @@ char KERNEL[] = "KERNEL.SYS";
 extern int VA_CDECL printf(CONST char * fmt, ...);
 extern int VA_CDECL sprintf(char * buff, CONST char * fmt, ...);
 
-#ifdef __WATCOMC__
+#if defined(__WATCOMC__)
 unsigned _dos_close(int handle);
 #define close _dos_close
 #define SEEK_SET 0
@@ -44,6 +46,11 @@ unsigned long lseek(int fildes, unsigned long offset, int whence);
       parm [bx] [dx cx] [ax] \
       value [dx ax];
 
+#elif defined(__GNUC__)
+#include <unistd.h>
+#include <fcntl.h>
+#define memicmp strncasecmp
+#define O_BINARY 0
 #else
 #include <io.h>
 #ifndef SEEK_SET

sys/sys.c

@@ -48,8 +48,11 @@
 #endif
 
 #include <stdlib.h>
+#ifndef __GNUC__
 #include <dos.h>
+#endif
 #include <ctype.h>
+#ifndef __GNUC__
 #include <fcntl.h>
 #include <sys/stat.h>
 #ifdef __TURBOC__
@@ -57,6 +60,7 @@
 #else
 #include <memory.h>
 #endif
+#endif
 #include <string.h>
 #ifdef __TURBOC__
 #include <dir.h>
@@ -91,7 +95,31 @@ extern int VA_CDECL sprintf(char * buff, CONST char * fmt, ...);
 
 #ifndef __WATCOMC__
 
+#ifdef __GNUC__
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <errno.h>
+#define O_BINARY 0
+#define stricmp strcasecmp
+#define memicmp strncasecmp
+union REGS {
+  struct {
+    unsigned char al, ah, bl, bh, cl, ch, dl, dh;
+  } h;
+  struct {
+    unsigned short ax, bx, cx, dx, si, di, cflag;
+  } x;
+};
+struct SREGS {
+  unsigned short ds, es;
+};
+struct _diskfree_t {
+  unsigned short avail_clusters, sectors_per_cluster, bytes_per_sector;
+};
+#else
 #include <io.h>
+#endif
 
 /* returns current DOS drive, A=0, B=1,C=2, ... */
 #ifdef __TURBOC__
@@ -973,7 +1001,7 @@ void reset_drive(int DosDrive);
 #pragma aux reset_drive = \
       "push ds" \
       "inc dx" \
-      "mov ah, 0xd" \ 
+      "mov ah, 0xd" \
       "int 0x21" \
       "mov ah,0x32" \
       "int 0x21" \
@@ -1798,7 +1826,7 @@ BOOL copy(const BYTE *source, COUNT drive, const BYTE * filename)
   {
     ULONG filesize;
     UWORD theseg;
-    BYTE far *buffer, far *bufptr;
+    BYTE far *buffer; BYTE far *bufptr;
     UWORD offs;
     unsigned chunk_size;