/****************************************************************/ /* */ /* main.c */ /* DOS-C */ /* */ /* Main Kernel Functions */ /* */ /* Copyright (c) 1995, 1996 */ /* Pasquale J. Villani */ /* All Rights Reserved */ /* */ /* This file is part of DOS-C. */ /* */ /* DOS-C is free software; you can redistribute it and/or */ /* modify it under the terms of the GNU General Public License */ /* as published by the Free Software Foundation; either version */ /* 2, or (at your option) any later version. */ /* */ /* DOS-C is distributed in the hope that it will be useful, but */ /* WITHOUT ANY WARRANTY; without even the implied warranty of */ /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */ /* the GNU General Public License for more details. */ /* */ /* You should have received a copy of the GNU General Public */ /* License along with DOS-C; see the file COPYING. If not, */ /* write to the Free Software Foundation, Inc., */ /* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ /****************************************************************/ #include "portab.h" #include "init-mod.h" #include "dyndata.h" #include "debug.h" #ifdef VERSION_STRINGS static BYTE *mainRcsId = "$Id: main.c 1699 2012-01-16 20:45:44Z perditionc $"; #endif static char copyright[] = "(C) Copyright 1995-2012 Pasquale J. Villani and The FreeDOS Project.\n" "All Rights Reserved. This is free software and comes with ABSOLUTELY NO\n" "WARRANTY; you can redistribute it and/or modify it under the terms of the\n" "GNU General Public License as published by the Free Software Foundation;\n" "either version 2, or (at your option) any later version.\n"; struct _KernelConfig InitKernelConfig BSS_INIT({0}); STATIC VOID InitIO(void); STATIC VOID update_dcb(struct dhdr FAR *); STATIC VOID init_kernel(VOID); STATIC VOID signon(VOID); STATIC VOID kernel(VOID); STATIC VOID FsConfig(VOID); STATIC VOID InitPrinters(VOID); STATIC VOID InitSerialPorts(VOID); STATIC void CheckContinueBootFromHarddisk(void); STATIC void setup_int_vectors(void); #ifdef _MSC_VER BYTE _acrtused = 0; __segment DosDataSeg = 0; /* serves for all references to the DOS DATA segment necessary for MSC+our funny linking model */ __segment DosTextSeg = 0; #endif struct lol FAR *LoL #ifndef __GNUC__ /* cannot initialize from far data with GCC */ = &DATASTART; #endif ; VOID ASMCFUNC FreeDOSmain(void) { unsigned char drv; unsigned char FAR *p; #ifdef _MSC_VER extern FAR prn_dev; DosDataSeg = (__segment) & DATASTART; DosTextSeg = (__segment) & prn_dev; #endif /* clear the Init BSS area (what normally the RTL does */ memset(_ib_start, 0, _ib_end - _ib_start); /* if the kernel has been UPX'ed, CONFIG info is stored at 50:e2 ..fc and the bootdrive (passed from BIOS) 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 */ { fmemcpy(&InitKernelConfig, p+2, sizeof(InitKernelConfig)); drv = *p + 1; *(DWORD FAR *)(p+2) = 0; } else { *p = drv - 1; fmemcpy(&InitKernelConfig, &LowKernelConfig, sizeof(InitKernelConfig)); } if (drv >= 0x80) drv = 3; /* C: */ LoL->BootDrive = drv; /* install DOS API and other interrupt service routines, basic kernel functionality works */ setup_int_vectors(); CheckContinueBootFromHarddisk(); /* display copyright info and kernel emulation status */ signon(); /* initialize all internal variables, process CONFIG.SYS, load drivers, etc */ init_kernel(); #ifdef DEBUG /* Non-portable message kludge alert! */ printf("KERNEL: Boot drive = %c\n", 'A' + LoL->BootDrive - 1); #endif DoInstall(); kernel(); } /* InitializeAllBPBs() or MakeNortonDiskEditorHappy() it has been determined, that FDOS's BPB tables are initialized, only when used (like DIR H:). at least one known utility (norton DE) seems to access them directly. ok, so we access for all drives, that the stuff gets build */ void InitializeAllBPBs(VOID) { static char filename[] = "A:-@JUNK@-.TMP"; int drive, fileno; for (drive = 'C'; drive < 'A' + LoL->nblkdev; drive++) { filename[0] = drive; if ((fileno = open(filename, O_RDONLY)) >= 0) close(fileno); } } STATIC void PSPInit(void) { psp far *p = MK_FP(DOS_PSP, 0); /* Clear out new psp first */ fmemset(p, 0, sizeof(psp)); /* initialize all entries and exits */ /* CP/M-like exit point */ p->ps_exit = 0x20cd; /* CP/M-like entry point - call far to special entry */ p->ps_farcall = 0x9a; p->ps_reentry = MK_FP(0, 0x30 * 4); /* unix style call - 0xcd 0x21 0xcb (int 21, retf) */ p->ps_unix[0] = 0xcd; p->ps_unix[1] = 0x21; p->ps_unix[2] = 0xcb; /* Now for parent-child relationships */ /* parent psp segment */ p->ps_parent = FP_SEG(p); /* previous psp pointer */ p->ps_prevpsp = MK_FP(0xffff,0xffff); /* Environment and memory useage parameters */ /* memory size in paragraphs */ /* p->ps_size = 0; clear from above */ /* environment paragraph */ p->ps_environ = DOS_PSP + 8; /* terminate address */ p->ps_isv22 = getvec(0x22); /* break address */ p->ps_isv23 = getvec(0x23); /* critical error address */ p->ps_isv24 = getvec(0x24); /* user stack pointer - int 21 */ /* p->ps_stack = NULL; clear from above */ /* File System parameters */ /* maximum open files */ p->ps_maxfiles = 20; fmemset(p->ps_files, 0xff, 20); /* open file table pointer */ p->ps_filetab = p->ps_files; /* first command line argument */ /* p->ps_fcb1.fcb_drive = 0; already set */ fmemset(p->ps_fcb1.fcb_fname, ' ', FNAME_SIZE + FEXT_SIZE); /* second command line argument */ /* p->ps_fcb2.fcb_drive = 0; already set */ fmemset(p->ps_fcb2.fcb_fname, ' ', FNAME_SIZE + FEXT_SIZE); /* local command line */ /* p->ps_cmd.ctCount = 0; command tail, already set */ p->ps_cmd.ctBuffer[0] = 0xd; /* command tail */ } #ifndef __WATCOMC__ /* for WATCOMC we can use the ones in task.c */ intvec getvec(unsigned char intno) { intvec iv; disable(); iv = *(intvec FAR *)MK_FP(0,4 * (intno)); enable(); return iv; } void setvec(unsigned char intno, intvec vector) { disable(); *(intvec FAR *)MK_FP(0,4 * intno) = vector; enable(); } #endif STATIC void setup_int_vectors(void) { static struct vec { unsigned char intno; size_t handleroff; } vectors[] = { /* all of these are in the DOS DS */ { 0x0, FP_OFF(int0_handler) }, /* zero divide */ { 0x1, FP_OFF(empty_handler) }, /* single step */ { 0x3, FP_OFF(empty_handler) }, /* debug breakpoint */ { 0x6, FP_OFF(int6_handler) }, /* invalid opcode */ { 0x19, FP_OFF(int19_handler) }, { 0x20, FP_OFF(int20_handler) }, { 0x21, FP_OFF(int21_handler) }, { 0x22, FP_OFF(int22_handler) }, { 0x24, FP_OFF(int24_handler) }, { 0x25, FP_OFF(low_int25_handler) }, { 0x26, FP_OFF(low_int26_handler) }, { 0x27, FP_OFF(int27_handler) }, { 0x28, FP_OFF(int28_handler) }, { 0x2a, FP_OFF(int2a_handler) }, { 0x2f, FP_OFF(int2f_handler) } }; struct vec *pvec; struct lowvec FAR *plvec; int i; for (plvec = intvec_table; plvec < intvec_table + 5; plvec++) plvec->isv = getvec(plvec->intno); for (i = 0x23; i <= 0x3f; i++) setvec(i, DOSDATA(empty_handler)); HaltCpuWhileIdle = 0; for (pvec = vectors; pvec < vectors + (sizeof vectors/sizeof *pvec); pvec++) setvec(pvec->intno, (intvec)MK_FP(FP_SEG(DOSDATA(empty_handler)), pvec->handleroff)); pokeb(0, 0x30 * 4, 0xea); pokel(0, 0x30 * 4 + 1, (ULONG)cpm_entry); /* these two are in the device driver area LOWTEXT (0x70) */ setvec(0x1b, got_cbreak); setvec(0x29, int29_handler); /* required for printf! */ } STATIC void init_kernel(void) { COUNT i; LoL->os_setver_major = LoL->os_major = MAJOR_RELEASE; LoL->os_setver_minor = LoL->os_minor = MINOR_RELEASE; /* Init oem hook - returns memory size in KB */ ram_top = init_oem(); /* move kernel to high conventional RAM, just below the init code */ #ifdef __WATCOMC__ lpTop = MK_FP(_CS, 0); #else lpTop = MK_FP(_CS - (FP_OFF(_HMATextEnd) + 15) / 16, 0); #endif MoveKernel(FP_SEG(lpTop)); lpTop = MK_FP(FP_SEG(lpTop) - 0xfff, 0xfff0); /* Initialize IO subsystem */ InitIO(); InitPrinters(); InitSerialPorts(); init_PSPSet(DOS_PSP); set_DTA(MK_FP(DOS_PSP, 0x80)); PSPInit(); Init_clk_driver(); /* Do first initialization of system variable buffers so that */ /* we can read config.sys later. */ /* use largest possible value for the initial CDS */ LoL->lastdrive = 26; /* init_device((struct dhdr FAR *)&blk_dev, NULL, 0, &ram_top); */ blk_dev.dh_name[0] = dsk_init(); PreConfig(); /* Number of units */ if (blk_dev.dh_name[0] > 0) update_dcb(&blk_dev); /* Now config the temporary file system */ FsConfig(); /* Now process CONFIG.SYS */ DoConfig(0); DoConfig(1); /* initialize near data and MCBs */ PreConfig2(); /* and process CONFIG.SYS one last time for device drivers */ DoConfig(2); /* Close all (device) files */ for (i = 0; i < 20; i++) close(i); /* and do final buffer allocation. */ PostConfig(); /* Init the file system one more time */ FsConfig(); configDone(); InitializeAllBPBs(); } STATIC VOID FsConfig(VOID) { struct dpb FAR *dpb = LoL->DPBp; int i; /* Initialize the current directory structures */ for (i = 0; i < LoL->lastdrive; i++) { struct cds FAR *pcds_table = &LoL->CDSp[i]; fmemcpy(pcds_table->cdsCurrentPath, "A:\\\0", 4); pcds_table->cdsCurrentPath[0] += i; if (i < LoL->nblkdev && (ULONG) dpb != 0xffffffffl) { pcds_table->cdsDpb = dpb; pcds_table->cdsFlags = CDSPHYSDRV; dpb = dpb->dpb_next; } else { pcds_table->cdsFlags = 0; } pcds_table->cdsStrtClst = 0xffff; pcds_table->cdsParam = 0xffff; pcds_table->cdsStoreUData = 0xffff; pcds_table->cdsJoinOffset = 2; } /* Log-in the default drive. */ init_setdrive(LoL->BootDrive - 1); /* The system file tables need special handling and are "hand */ /* built. Included is the stdin, stdout, stdaux and stdprn. */ /* a little bit of shuffling is necessary for compatibility */ /* sft_idx=0 is /dev/aux */ open("AUX", O_RDWR); /* handle 1, sft_idx=1 is /dev/con (stdout) */ open("CON", O_RDWR); /* 3 is /dev/aux */ dup2(STDIN, STDAUX); /* 0 is /dev/con (stdin) */ dup2(STDOUT, STDIN); /* 2 is /dev/con (stdin) */ dup2(STDOUT, STDERR); /* 4 is /dev/prn */ open("PRN", O_WRONLY); /* Initialize the disk buffer management functions */ /* init_call_init_buffers(); done from CONFIG.C */ } STATIC VOID signon() { printf("\r%S" "Kernel compatibility %d.%d - " #if defined(__BORLANDC__) "BORLANDC" #elif defined(__TURBOC__) "TURBOC" #elif defined(_MSC_VER) "MSC" #elif defined(__WATCOMC__) "WATCOMC" #elif defined(__GNUC__) "GNUC" /* this is hypothetical only */ #else #error Unknown compiler generate some bullshit error here, as the compiler should be known #endif #if defined (I386) " - 80386 CPU required" #elif defined (I186) " - 80186 CPU required" #endif #ifdef WITHFAT32 " - FAT32 support" #endif "\n\n%s", MK_FP(FP_SEG(LoL), FP_OFF(LoL->os_release)), MAJOR_RELEASE, MINOR_RELEASE, copyright); } STATIC void kernel() { CommandTail Cmd; if (master_env[0] == '\0') /* some shells panic on empty master env. */ strcpy(master_env, "PATH=."); fmemcpy(MK_FP(DOS_PSP + 8, 0), master_env, sizeof(master_env)); /* process 0 */ /* Execute command.com from the drive we just booted from */ memset(Cmd.ctBuffer, 0, sizeof(Cmd.ctBuffer)); strcpy(Cmd.ctBuffer, Config.cfgInitTail); for (Cmd.ctCount = 0; Cmd.ctCount < sizeof(Cmd.ctBuffer); Cmd.ctCount++) if (Cmd.ctBuffer[Cmd.ctCount] == '\r') break; /* if stepping CONFIG.SYS (F5/F8), tell COMMAND.COM about it */ /* 3 for string + 2 for "\r\n" */ if (Cmd.ctCount < sizeof(Cmd.ctBuffer) - 5) { char *insertString = NULL; if (singleStep) insertString = " /Y"; /* single step AUTOEXEC */ if (SkipAllConfig) insertString = " /D"; /* disable AUTOEXEC */ if (insertString) { /* insert /D, /Y as first argument */ char *p, *q; for (p = Cmd.ctBuffer; p < &Cmd.ctBuffer[Cmd.ctCount]; p++) { if (*p == ' ' || *p == '\t' || *p == '\r') { for (q = &Cmd.ctBuffer[Cmd.ctCount + 1]; q >= p; q--) q[3] = q[0]; memcpy(p, insertString, 3); break; } } /* save buffer -- on the stack it's fine here */ Config.cfgInitTail = Cmd.ctBuffer; } } init_call_p_0(&Config); /* go execute process 0 (the shell) */ } /* check for a block device and update device control block */ STATIC VOID update_dcb(struct dhdr FAR * dhp) { REG COUNT Index; COUNT nunits = dhp->dh_name[0]; struct dpb FAR *dpb; if (LoL->nblkdev == 0) dpb = LoL->DPBp; else { for (dpb = LoL->DPBp; (ULONG) dpb->dpb_next != 0xffffffffl; dpb = dpb->dpb_next) ; dpb = dpb->dpb_next = KernelAlloc(nunits * sizeof(struct dpb), 'E', Config.cfgDosDataUmb); } for (Index = 0; Index < nunits; Index++) { dpb->dpb_next = dpb + 1; dpb->dpb_unit = LoL->nblkdev; dpb->dpb_subunit = Index; dpb->dpb_device = dhp; dpb->dpb_flags = M_CHANGED; if ((LoL->CDSp != 0) && (LoL->nblkdev < LoL->lastdrive)) { LoL->CDSp[LoL->nblkdev].cdsDpb = dpb; LoL->CDSp[LoL->nblkdev].cdsFlags = CDSPHYSDRV; } ++dpb; ++LoL->nblkdev; } (dpb - 1)->dpb_next = (void FAR *)0xFFFFFFFFl; } /* If cmdLine is NULL, this is an internal driver */ BOOL init_device(struct dhdr FAR * dhp, char *cmdLine, COUNT mode, char FAR **r_top) { request rq; char name[8]; if (cmdLine) { char *p, *q, ch; int i; p = q = cmdLine; for (;;) { ch = *p; if (ch == '\0' || ch == ' ' || ch == '\t') break; p++; if (ch == '\\' || ch == '/' || ch == ':') q = p; /* remember position after path */ } for (i = 0; i < 8; i++) { ch = '\0'; if (p != q && *q != '.') ch = *q++; /* copy name, without extension */ name[i] = ch; } } rq.r_unit = 0; rq.r_status = 0; rq.r_command = C_INIT; rq.r_length = sizeof(request); rq.r_endaddr = *r_top; rq.r_bpbptr = (void FAR *)(cmdLine ? cmdLine : "\n"); rq.r_firstunit = LoL->nblkdev; execrh((request FAR *) & rq, dhp); /* * Added needed Error handle */ if ((rq.r_status & (S_ERROR | S_DONE)) == S_ERROR) return TRUE; if (cmdLine) { /* Don't link in device drivers which do not take up memory */ if (rq.r_endaddr == (BYTE FAR *) dhp) return TRUE; /* Don't link in block device drivers which indicate no units */ if (!(dhp->dh_attr & ATTR_CHAR) && !rq.r_nunits) { rq.r_endaddr = (BYTE FAR *) dhp; return TRUE; } /* Fix for multisegmented device drivers: */ /* If there are multiple device drivers in a single driver file, */ /* only the END ADDRESS returned by the last INIT call should be */ /* the used. It is recommended that all the device drivers in */ /* the file return the same address */ if (FP_OFF(dhp->dh_next) == 0xffff) { KernelAllocPara(FP_SEG(rq.r_endaddr) + (FP_OFF(rq.r_endaddr) + 15)/16 - FP_SEG(dhp), 'D', name, mode); } /* Another fix for multisegmented device drivers: */ /* To help emulate the functionallity experienced with other DOS */ /* operating systems when calling multiple device drivers in a */ /* single driver file, save the end address returned from the */ /* last INIT call which will then be passed as the end address */ /* for the next INIT call. */ *r_top = (char FAR *)rq.r_endaddr; } if (!(dhp->dh_attr & ATTR_CHAR) && (rq.r_nunits != 0)) { dhp->dh_name[0] = rq.r_nunits; update_dcb(dhp); } if (dhp->dh_attr & ATTR_CONIN) LoL->syscon = dhp; else if (dhp->dh_attr & ATTR_CLOCK) LoL->clock = dhp; return FALSE; } STATIC void InitIO(void) { struct dhdr far *device = &LoL->nul_dev; /* Initialize driver chain */ do { init_device(device, NULL, 0, &lpTop); device = device->dh_next; } while (FP_OFF(device) != 0xffff); } /* issue an internal error message */ VOID init_fatal(BYTE * err_msg) { printf("\nInternal kernel error - %s\nSystem halted\n", err_msg); for (;;) ; } /* Initialize all printers this should work. IMHO, this might also be done on first use of printer, as I never liked the noise by a resetting printer, and I usually much more often reset my system, then I print :-) */ STATIC VOID InitPrinters(VOID) { iregs r; int num_printers, i; init_call_intr(0x11, &r); /* get equipment list */ num_printers = (r.a.x >> 14) & 3; /* bits 15-14 */ for (i = 0; i < num_printers; i++) { r.a.x = 0x0100; /* initialize printer */ r.d.x = i; init_call_intr(0x17, &r); } } STATIC VOID InitSerialPorts(VOID) { iregs r; int serial_ports, i; init_call_intr(0x11, &r); /* get equipment list */ serial_ports = (r.a.x >> 9) & 7; /* bits 11-9 */ for (i = 0; i < serial_ports; i++) { r.a.x = 0xA3; /* initialize serial port to 2400,n,8,1 */ r.d.x = i; init_call_intr(0x14, &r); } } /***************************************************************** if kernel.config.BootHarddiskSeconds is set, the default is to boot from harddisk, because the user is assumed to just have forgotten to remove the floppy/bootable CD from the drive. user has some seconds to hit ANY key to continue to boot from floppy/cd, else the system is booted from HD */ STATIC int EmulatedDriveStatus(int drive,char statusOnly) { iregs r; char buffer[0x13]; buffer[0] = 0x13; r.a.b.h = 0x4b; /* bootable CDROM - get status */ r.a.b.l = statusOnly; r.d.b.l = (char)drive; r.si = (int)buffer; init_call_intr(0x13, &r); if (r.flags & 1) return FALSE; return TRUE; } STATIC void CheckContinueBootFromHarddisk(void) { char *bootedFrom = "Floppy/CD"; iregs r; int key; if (InitKernelConfig.BootHarddiskSeconds == 0) return; if (LoL->BootDrive >= 3) { #if 0 if (!EmulatedDriveStatus(0x80,1)) #endif { /* already booted from HD */ return; } } else { #if 0 if (!EmulatedDriveStatus(0x00,1)) #endif bootedFrom = "Floppy"; } printf("\n" "\n" "\n" " Hit any key within %d seconds to continue boot from %s\n" " Hit 'H' or wait %d seconds to boot from Harddisk\n", InitKernelConfig.BootHarddiskSeconds, bootedFrom, InitKernelConfig.BootHarddiskSeconds ); key = GetBiosKey(InitKernelConfig.BootHarddiskSeconds); if (key != -1 && (key & 0xff) != 'h' && (key & 0xff) != 'H') { /* user has hit a key, continue to boot from floppy/CD */ printf("\n"); return; } /* reboot from harddisk */ EmulatedDriveStatus(0x00,0); EmulatedDriveStatus(0x80,0); /* now jump and run */ r.a.x = 0x0201; r.c.x = 0x0001; r.d.x = 0x0080; r.b.x = 0x7c00; r.es = 0; 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 } }