# fork.c

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    00001 /*****************************************************************************************
    00002  Copyright (c) 2002-2004 The UbixOS Project
    00003  All rights reserved.
    00004
    00005  Redistribution and use in source and binary forms, with or without modification, are
    00006  permitted provided that the following conditions are met:
    00007
    00008  Redistributions of source code must retain the above copyright notice, this list of
    00009  conditions, the following disclaimer and the list of authors.  Redistributions in binary
    00010  form must reproduce the above copyright notice, this list of conditions, the following
    00011  disclaimer and the list of authors in the documentation and/or other materials provided
    00012  with the distribution. Neither the name of the UbixOS Project nor the names of its
    00013  contributors may be used to endorse or promote products derived from this software
    00014  without specific prior written permission.
    00015
    00016  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
    00017  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
    00018  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
    00019  THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
    00020  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
    00021  OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    00022  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
    00023  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
    00024  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    00025
    00026  $Id: fork_8c-source.html 88 2016-01-12 00:11:29Z reddawg $
    00027
    00028 *****************************************************************************************/
    00029
    00030 #include <ubixos/fork.h>
    00031 #include <ubixos/types.h>
    00032 #include <ubixos/sched.h>
    00033 #include <ubixos/tty.h>
    00034 #include <ubixos/vitals.h>
    00035 #include <vmm/vmm.h>
    00036 #include <string.h>
    00037 #include <assert.h>
    00038
    00039 /*****************************************************************************************
    00040  Functoin: static int fork_copyProcess(struct taskStruct *newProcess,long ebp,long edi,
    00041              long esi, long none,long ebx,long ecx,long edx,long eip,long cs,long eflags,
    00042              long esp,long ss)
    00043
    00044  Desc: This function will copy a process
    00045
    00046  Notes:
    00047
    00048 *****************************************************************************************/
    00049 /* Had to remove static though tihs function is only used in this file */
    00050 int fork_copyProcess(struct taskStruct *newProcess,long ebp,long edi,long esi,long none,long ebx,long ecx,long edx,long eip,long cs,long eflags,long esp,long ss) {
    00051   volatile struct taskStruct * tmpProcPtr = newProcess;
    00052   assert(newProcess);
    00053   assert(_current);
    00054
    00055   /* Set Up New Tasks Information */
    00056   memcpy(newProcess->oInfo.cwd,_current->oInfo.cwd,1024);
    00057
    00058   newProcess->tss.eip          = eip;
    00059   newProcess->oInfo.vmStart    = _current->oInfo.vmStart;
    00060   newProcess->term             = _current->term;
    00061   newProcess->term->owner      = newProcess->id;
    00062   newProcess->uid              = _current->uid;
    00063   newProcess->gid              = _current->gid;
    00064   newProcess->tss.back_link    = 0x0;
    00065   newProcess->tss.esp0         = _current->tss.esp0;
    00066   newProcess->tss.ss0          = 0x10;
    00067   newProcess->tss.esp1         = 0x0;
    00068   newProcess->tss.ss1          = 0x0;
    00069   newProcess->tss.esp2         = 0x0;
    00070   newProcess->tss.ss2          = 0x0;
    00071   newProcess->tss.eflags       = eflags;
    00072   newProcess->tss.eax          = 0x0;
    00073   newProcess->tss.ebx          = ebx;
    00074   newProcess->tss.ecx          = ecx;
    00075   newProcess->tss.edx          = edx;
    00076   newProcess->tss.esi          = esi;
    00077   newProcess->tss.edi          = edi;
    00078   newProcess->tss.ebp          = ebp;
    00079   newProcess->tss.esp          = esp;
    00080   newProcess->tss.cs           = cs & 0xFF;
    00081   newProcess->tss.ss           = ss & 0xFF;
    00082   newProcess->tss.ds           = _current->tss.ds & 0xFF;
    00083   newProcess->tss.fs           = _current->tss.fs & 0xFF;
    00084   newProcess->tss.gs           = _current->tss.gs & 0xFF;
    00085   newProcess->tss.es           = _current->tss.es & 0xFF;
    00086   newProcess->tss.ldt          = 0x18;
    00087   newProcess->tss.trace_bitmap = 0x0000;
    00088   newProcess->tss.io_map       = 0x8000;
    00089   /* Create A Copy Of The VM Space For New Task */
    00090   newProcess->tss.cr3 = (uInt32)vmmCopyVirtualSpace(newProcess->id);
    00091   newProcess->state = FORK;
    00092
    00093   /* Fix gcc optimization problems */
    00094   while (tmpProcPtr->state == FORK) sched_yield();
    00095
    00096   /* Return Id of Proccess */
    00097   return(newProcess->id);
    00098   }
    00099
    00100 /*****************************************************************************************
    00101  Functoin: void sysFork();
    00102
    00103  Desc: This function will fork a new task
    00104
    00105  Notes:
    00106
    00107    08/01/02 - This Seems To Be Working Fine However I'm Not Sure If I
    00108               Chose The Best Path To Impliment It I Guess We Will See
    00109               What The Future May Bring
    00110
    00111 *****************************************************************************************/
    00112 asm(
    00113   ".globl sysFork           \n"
    00114   "sysFork:                 \n"
    00115   "  xor   %eax,%eax        \n"
    00116   "  call  schedNewTask     \n"
    00117   "  testl %eax,%eax        \n"
    00118   "  je fork_ret            \n"
    00119   "  pushl %esi             \n"
    00120   "  pushl %edi             \n"
    00121   "  pushl %ebp             \n"
    00122   "  pushl %eax             \n"
    00123   "  call  fork_copyProcess \n"
    00124   "  movl  %eax,(%ebx)      \n"
    00125   "  addl  $16,%esp         \n"
    00126   "fork_ret:                \n"
    00127   "  ret                    \n"
    00128   );
    00129
    00130 /***
    00131  END
    00132  ***/
    00133