rom/exec/prepareexecbase.c

   1 /*
   2     Copyright © 1995-2011, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: Sets up the ExecBase a bit. (Mostly clearing).
   6     Lang:
   7 */
   8
   9 #include <aros/asmcall.h>
  10 #include <aros/debug.h>
  11 #include <aros/kernel.h>
  12 #include <clib/macros.h>
  13 #include <exec/types.h>
  14 #include <exec/lists.h>
  15 #include <exec/memory.h>
  16 #include <exec/memheaderext.h>
  17 #include <exec/resident.h>
  18 #include <exec/execbase.h>
  19 #include <exec/libraries.h>
  20 #include <aros/arossupportbase.h>
  21
  22 #include <string.h>
  23
  24 #include <proto/alib.h>
  25 #include <proto/exec.h>
  26 #include <proto/kernel.h>
  27
  28 #include LC_LIBDEFS_FILE
  29 #include "etask.h"
  30 #include "memory.h"
  31 #include "exec_util.h"
  32 #include "exec_debug.h"
  33 #include "exec_intern.h"
  34
  35 #undef kprintf /* This can't be used in the code here */
  36
  37 extern void *LIBFUNCTABLE[];
  38
  39 extern struct Resident Exec_resident; /* Need this for lib_IdString */
  40
  41 extern void Exec_TrapHandler(ULONG trapNum);
  42 AROS_LD3(ULONG, MakeFunctions,
  43          AROS_LDA(APTR, target, A0),
  44          AROS_LDA(CONST_APTR, functionArray, A1),
  45          AROS_LDA(CONST_APTR, funcDispBase, A2),
  46          struct ExecBase *, SysBase, 15, Exec);
  47
  48 /* Default finaliser. */
  49 static void Exec_TaskFinaliser(void)
  50 {
  51     /* Get rid of current task. */
  52     RemTask(SysBase->ThisTask);
  53 }
  54
  55 #undef kprintf
  56 #undef rkprintf
  57 #undef vkprintf
  58
  59 void _aros_not_implemented(char *X)
  60 {
  61     kprintf("Unsupported function at offset -0x%h in %s\n",
  62             ABS(*(WORD *)((&X)[-1]-2)),
  63             ((struct Library *)(&X)[-2])->lib_Node.ln_Name);
  64 }
  65
  66 struct Library *PrepareAROSSupportBase (struct MemHeader *mh)
  67 {
  68     struct AROSSupportBase *AROSSupportBase;
  69
  70     AROSSupportBase = Allocate(mh, sizeof(struct AROSSupportBase));
  71
  72     AROSSupportBase->kprintf = (void *)kprintf;
  73     AROSSupportBase->rkprintf = (void *)rkprintf;
  74     AROSSupportBase->vkprintf = (void *)vkprintf;
  75
  76     AROSSupportBase->StdOut = NULL;
  77     AROSSupportBase->DebugConfig = NULL;
  78
  79     return (struct Library *)AROSSupportBase;
  80 }
  81
  82 BOOL IsSysBaseValid(struct ExecBase *sysbase)
  83 {
  84     if (sysbase == NULL)
  85         return FALSE;
  86 #ifdef __mc68000
  87     if (((IPTR)sysbase) & 0x80000001)
  88         return FALSE;
  89 #endif
  90     if (sysbase->ChkBase != ~(IPTR)sysbase)
  91         return FALSE;
  92     if (sysbase->SoftVer != VERSION_NUMBER)
  93         return FALSE;
  94     /* more tests? */
  95     return GetSysBaseChkSum(sysbase) == 0xffff;
  96 }
  97
  98 UWORD GetSysBaseChkSum(struct ExecBase *sysbase)
  99 {
 100      UWORD sum = 0;
 101      UWORD *p = (UWORD*)&sysbase->SoftVer;
 102      while (p <= &sysbase->ChkSum)
 103         sum += *p++;
 104      return sum;
 105 }
 106
 107 void SetSysBaseChkSum(void)
 108 {
 109      SysBase->ChkBase=~(IPTR)SysBase;
 110      SysBase->ChkSum = 0;
 111      SysBase->ChkSum = GetSysBaseChkSum(SysBase) ^ 0xffff;
 112 }
 113
 114 /*
 115  *  PrepareExecBase() will initialize the ExecBase to default values.
 116  *  MemHeader and ExecBase itself will already be added to appropriate
 117  *  lists. You don't need to do this yourself.
 118  *
 119  *  WARNING: this routine intentionally sets up global SysBase.
 120  *  This is done because:
 121  *  1. PrepareAROSSupportBase() calls Allocate() which relies on functional SysBase
 122  *  2. After PrepareAROSSupportBase() it is possible to call debug output functions
 123  *     (kprintf() etc). Yes, KernelBase is not set up yet, but remember that kernel.resource
 124  *     may have patched functions in AROSSupportBase so that KernelBase is not needed there.
 125  *  3. Existing ports (at least UNIX-hosted and Windows-hosted) rely on the fact that SysBase is
 126  *     set up here.
 127  *
 128  *  Resume: please be extremely careful, study existing code, and think five times if you decide to
 129  *  change this. You WILL break existing ports if you do not modify their code accordingly. There's
 130  *  nothing really bad in the fact that global SysBase is touched here and changing this does not
 131  *  really win something.
 132  *                                              Pavel Fedin <pavel_fedin@mail.ru>
 133  */
 134 struct ExecBase *PrepareExecBase(struct MemHeader *mh, struct TagItem *msg)
 135 {
 136     ULONG negsize = 0;
 137     VOID  **fp = LIBFUNCTABLE;
 138     APTR ColdCapture = NULL, CoolCapture = NULL, WarmCapture = NULL;
 139     APTR KickMemPtr = NULL, KickTagPtr = NULL, KickCheckSum = NULL;
 140     APTR mem;
 141     ULONG i;
 142     char *args;
 143
 144     /*
 145      * Copy reset proof pointers if old SysBase is valid.
 146      * Additional platform-specific code is needed in order to test
 147      * address validity. This routine should zero out SysBase if it is invalid.
 148      */
 149     if (IsSysBaseValid(SysBase))
 150     {
 151         ColdCapture  = SysBase->ColdCapture;
 152         CoolCapture  = SysBase->CoolCapture;
 153         WarmCapture  = SysBase->WarmCapture;
 154         KickMemPtr   = SysBase->KickMemPtr;
 155         KickTagPtr   = SysBase->KickTagPtr;
 156         KickCheckSum = SysBase->KickCheckSum;
 157     }
 158
 159     /* Calculate the size of the vector table */
 160     while (*fp++ != (VOID *) -1) negsize += LIB_VECTSIZE;
 161
 162     /* Align library base */
 163     negsize = AROS_ALIGN(negsize);
 164
 165     /* Allocate memory for library base */
 166     mem = stdAlloc(mh, negsize + sizeof(struct IntExecBase), MEMF_CLEAR, NULL, NULL);
 167     if (!mem)
 168         return NULL;
 169
 170     SysBase = mem + negsize;
 171
 172 #ifdef HAVE_PREPAREPLATFORM
 173     /* Setup platform-specific data */
 174     if (!Exec_PreparePlatform(&PD(SysBase), msg))
 175         return NULL;
 176 #endif
 177
 178     /* Setup function vectors */
 179     AROS_CALL3(ULONG, AROS_SLIB_ENTRY(MakeFunctions, Exec, 15),
 180               AROS_UFCA(APTR, SysBase, A0),
 181               AROS_UFCA(CONST_APTR, LIBFUNCTABLE, A1),
 182               AROS_UFCA(CONST_APTR, NULL, A2),
 183               struct ExecBase *, SysBase);
 184
 185     /* Set default values */
 186     SysBase->LibNode.lib_Node.ln_Type = NT_LIBRARY;
 187     SysBase->LibNode.lib_Node.ln_Pri  = -100;
 188     SysBase->LibNode.lib_Node.ln_Name = (char *)Exec_resident.rt_Name;
 189     SysBase->LibNode.lib_IdString     = (char *)Exec_resident.rt_IdString;
 190     SysBase->LibNode.lib_Version      = VERSION_NUMBER;
 191     SysBase->LibNode.lib_Revision     = REVISION_NUMBER;
 192     SysBase->LibNode.lib_OpenCnt      = 1;
 193     SysBase->LibNode.lib_NegSize      = negsize;
 194     SysBase->LibNode.lib_PosSize      = sizeof(struct IntExecBase);
 195     SysBase->LibNode.lib_Flags        = LIBF_CHANGED | LIBF_SUMUSED;
 196
 197     NEWLIST(&SysBase->MemList);
 198     SysBase->MemList.lh_Type = NT_MEMORY;
 199
 200     NEWLIST(&SysBase->ResourceList);
 201     SysBase->ResourceList.lh_Type = NT_RESOURCE;
 202
 203     NEWLIST(&SysBase->DeviceList);
 204     SysBase->DeviceList.lh_Type = NT_DEVICE;
 205
 206     NEWLIST(&SysBase->IntrList);
 207     SysBase->IntrList.lh_Type = NT_INTERRUPT;
 208
 209     NEWLIST(&SysBase->LibList);
 210     SysBase->LibList.lh_Type = NT_LIBRARY;
 211
 212     /* Add exec.library to system library list */
 213     ADDHEAD(&SysBase->LibList, &SysBase->LibNode.lib_Node);
 214
 215     NEWLIST(&SysBase->PortList);
 216     SysBase->PortList.lh_Type = NT_MSGPORT;
 217
 218     NEWLIST(&SysBase->TaskReady);
 219     SysBase->TaskReady.lh_Type = NT_TASK;
 220
 221     NEWLIST(&SysBase->TaskWait);
 222     SysBase->TaskWait.lh_Type = NT_TASK;
 223
 224     NEWLIST(&SysBase->SemaphoreList);
 225     SysBase->TaskWait.lh_Type = NT_SEMAPHORE;
 226
 227     NEWLIST(&SysBase->ex_MemHandlers);
 228
 229     for (i = 0; i < 5; i++)
 230     {
 231         NEWLIST(&SysBase->SoftInts[i].sh_List);
 232         SysBase->SoftInts[i].sh_List.lh_Type = NT_INTERRUPT;
 233     }
 234
 235     NEWLIST(&PrivExecBase(SysBase)->ResetHandlers);
 236     NEWLIST(&PrivExecBase(SysBase)->AllocMemList);
 237
 238     InitSemaphore(&PrivExecBase(SysBase)->MemListSem);
 239     InitSemaphore(&PrivExecBase(SysBase)->LowMemSem);
 240
 241     SysBase->SoftVer        = VERSION_NUMBER;
 242     SysBase->Quantum        = 4;
 243     SysBase->TaskTrapCode   = Exec_TrapHandler;
 244     SysBase->TaskExceptCode = NULL;
 245     SysBase->TaskExitCode   = Exec_TaskFinaliser;
 246     SysBase->TaskSigAlloc   = 0xFFFF;
 247     SysBase->TaskTrapAlloc  = 0;
 248
 249     /* Parse some arguments from command line */
 250     args = (char *)LibGetTagData(KRN_CmdLine, 0, msg);
 251     if (args)
 252     {
 253         char *opts;
 254
 255         /*
 256          * Enable mungwall before the first AllocMem().
 257          * Yes, we have actually already called stdAlloc() once
 258          * in order to allocate memory for SysBase itself, however
 259          * this is not a real problem because it is never going
 260          * to be freed.
 261          *
 262          * We store mungwall setting in private flags because it must not be
 263          * switched at runtime (or hard crash will happen).
 264          */
 265         opts = strcasestr(args, "mungwall");
 266         if (opts)
 267             PrivExecBase(SysBase)->IntFlags = EXECF_MungWall;
 268
 269         opts = strcasestr(args, "stacksnoop");
 270         if (opts)
 271             PrivExecBase(SysBase)->IntFlags = EXECF_StackSnoop;
 272
 273         /*
 274          * Parse system runtime debug flags.
 275          * These are public. In future they will be editable by prefs program.
 276          * However in order to be able to turn them on during early startup,
 277          * we apply them also here.
 278          */
 279         opts = strcasestr(args, "sysdebug=");
 280         if (opts)
 281             SysBase->ex_DebugFlags = ParseFlags(&opts[9], ExecFlagNames);
 282     }
 283
 284     PrivExecBase(SysBase)->TaskStorageSize = sizeof(struct IntETask) + TASKSTORAGEPUDDLE;
 285     NEWLIST(&PrivExecBase(SysBase)->TaskStorageSlots);
 286
 287     SetSysBaseChkSum();
 288
 289     /* Add our initial MemHeader */
 290     ADDHEAD(&SysBase->MemList, &mh->mh_Node);
 291
 292     /* Bring back saved values (or NULLs) */
 293     SysBase->ColdCapture  = ColdCapture;
 294     SysBase->CoolCapture  = CoolCapture;
 295     SysBase->WarmCapture  = WarmCapture;
 296     SysBase->KickMemPtr   = KickMemPtr;
 297     SysBase->KickTagPtr   = KickTagPtr;
 298     SysBase->KickCheckSum = KickCheckSum;
 299
 300     SysBase->DebugAROSBase = PrepareAROSSupportBase(mh);
 301
 302     return SysBase;
 303 }