hsys.c

这个是LINUX下的GDB调度工具的源码

/* 
 * Copyright (C) 1995 Advanced RISC Machines Limited. All rights reserved.
 * 
 * This software may be freely used, copied, modified, and distributed
 * provided that the above copyright notice is preserved in all copies of the
 * software.
 */

/*
 * Host C Library support functions.
 *
 * $Revision: 1.3 $
 *     $Date: 1999/11/01 13:31:36 $
 */

#ifdef DEBUG
#  include <ctype.h>
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <errno.h>
#include <time.h>

#include "adp.h"
#include "host.h"
#include "ardi.h"
#include "buffers.h"
#include "channels.h"        /* Channel interface. */
#include "angel_endian.h"
#include "logging.h"         /* Angel support functions. */
#include "msgbuild.h"
#include "sys.h"    
#include "hsys.h"      /* Function and structure declarations. */
#include "hostchan.h"

#define FILEHANDLE int

/* Note: no statics allowed.  All globals must be malloc()ed on the heap.
   The state struct is used for this purpose.  See 'hsys.h'.                */
/* This is the message handler function passed to the channel manager in
   HostSysInit.  It is called whenever a message is received. 'buffptr'
   points to the message body.  Functionality is provided by the debugger
   toolkit.  The routine is very loosely based on the HandleSWI routine from
   armos.c in the armulator source.                                         */
/* These routines could be tested by providing a simple interface to armsd, 
   and running them in that.   */


/* taken staight from armulator source */
#ifdef __riscos
  extern int _fisatty(FILE *);
# define isatty_(f) _fisatty(f)
# define EMFILE -1
# define EBADF -1
  int _kernel_escape_seen(void) { return 0 ;}
#else
# if defined(_WINDOWS) || defined(_CONSOLE)
#   define isatty_(f) (f == stdin || f == stdout)
# else
#   ifdef __ZTC__
#     include <io.h>
#     define isatty_(f) isatty((f)->_file)
#   else
#     ifdef macintosh
#       include <ioctl.h>
#       define isatty_(f) (~ioctl((f)->_file,FIOINTERACTIVE,NULL))
#     else
#       define isatty_(f) isatty(fileno(f))
#     endif
#   endif
# endif
#endif

/* Set up the state block, filetable and register the C lib callback fn */
int HostSysInit(const struct Dbg_HostosInterface *hostif, char **cmdline,
                hsys_state **stateptr)
{
  ChannelCallback HandleMessageFPtr = (ChannelCallback) HandleSysMessage;
  int i;
  *stateptr = (hsys_state *)malloc(sizeof(hsys_state));

  if (*stateptr == NULL) return RDIError_OutOfStore;

  (*stateptr)->hostif=hostif;
  (*stateptr)->last_errno=0;
  (*stateptr)->OSptr=(OSblock *)malloc(sizeof(OSblock));
  if ((*stateptr)->OSptr == NULL) return RDIError_OutOfStore;
  for (i=0; i<UNIQUETEMPS; i++) (*stateptr)->OSptr->TempNames[i]=NULL;
  for (i=0; i<HSYS_FOPEN_MAX; i++) {
       (*stateptr)->OSptr->FileTable[i]=NULL;
       (*stateptr)->OSptr->FileFlags[i]=0;
  }
  (*stateptr)->CommandLine=cmdline;

  return Adp_ChannelRegisterRead(CI_CLIB, (ChannelCallback)HandleMessageFPtr,
                                 *stateptr);
}

/* Shut down the Clib support, this will probably never get called though */
int HostSysExit(hsys_state *stateptr)
{
  free(stateptr->OSptr);
  free(stateptr);
  return RDIError_NoError;
}

#ifdef DEBUG
static void DebugCheckNullTermString(char *prefix, bool nl,
                                     unsigned int len, unsigned char *strp)
{
    printf("%s: %d: ", prefix, len);
    if (strp[len]=='\0')
       printf("\"%s\"", strp);
    else
       printf("NOT NULL TERMINATED");
    if (nl)
       printf("\n");
    else
    {
        printf(" ");
        fflush(stdout);
    }
}

#ifdef NEED_SYSERRLIST
extern int sys_nerr;
extern char *sys_errlist[];
#endif

static char *DebugStrError(int last_errno)
{
    if (last_errno < sys_nerr)
       return sys_errlist[last_errno];
    else
       return "NO MSG (errno>sys_nerr)";
}

static void DebugCheckErr(char *prefix, bool nl, int err, int last_errno)
{
    printf("\t%s: returned ", prefix);
    if (err == 0)
       printf("okay");
    else
       printf("%d, errno = %d \"%s\"", err, last_errno,
              DebugStrError(last_errno));
    if (nl)
       printf("\n");
    else
    {
        printf(" ");
        fflush(stdout);
    }
}

static void DebugCheckNonNull(char *prefix, bool nl,
                              void *handle, int last_errno)
{
    printf("\t%s: returned ", prefix);
    if (handle != NULL)
       printf("okay [%08x]", (unsigned int)handle);
    else
       printf("NULL, errno = %d \"%s\"", last_errno,
              DebugStrError(last_errno));
    if (nl)
       printf("\n");
    else
    {
        printf(" ");
        fflush(stdout);
    }
}

#define DebugPrintF(c) printf c;

#else

#define DebugCheckNullTermString(p, n, l, s)    ((void)(0))
#define DebugCheckErr(p, n, e, l)               ((void)(0))
#define DebugCheckNonNull(p, n, h, l)           ((void)(0))
#define DebugPrintF(c)                          ((void)(0))

#endif /* ifdef DEBUG ... else */

static FILE *hsysGetRealFileHandle(hsys_state *stateptr, int fh, char *flags)
{
    FILE *file_p = NULL;

    if (fh < 0 || fh >= HSYS_FOPEN_MAX)
    {
        stateptr->last_errno = EBADF;
        DebugPrintF(("\tfh %d out-of-bounds!\n", fh));
        return NULL;
    }
    else
    {
        file_p = stateptr->OSptr->FileTable[fh];
        if (file_p != NULL) {
            if (flags != NULL)
               *flags = stateptr->OSptr->FileFlags[fh];
        }
        else {
          stateptr->last_errno = EBADF;
          DebugPrintF(("\tFileTable[%d] is NULL\n", fh));
        }

        return file_p;
    }
}

int HandleSysMessage(Packet *packet, hsys_state *stateptr)
{
  unsigned int reason_code, mode, len, c, nbytes, nbtotal, nbtogo = 0;
  long posn, fl;
  char character;
  int err;

  /* Note: We must not free the buffer passed in as the callback handler */
  /* expects to do this.  Freeing any other buffers we have malloced */
  /* ourselves is acceptable */

  unsigned char *buffp = ((unsigned char *)BUFFERDATA(packet->pk_buffer))+16;
                                          /* buffp points to the parameters*/
                                          /* the invidual messages, excluding*/
                                          /* standard SYS fields (debugID, */
                                          /* osinfo and reasoncode) */
  unsigned char *buffhead = (unsigned char *)(packet->pk_buffer);

  int DebugID, OSInfo1, OSInfo2, count;

  const char* fmode[] = {"r","rb","r+","r+b",
                               "w","wb","w+","w+b",
                               "a","ab","a+","a+b",
                               "r","r","r","r"} /* last 4 are illegal */ ;

  FILEHANDLE fh;  /* fh is used as an index to the real file handle
                         * in OSptr */  
  FILE *fhreal;
  unpack_message(BUFFERDATA(buffhead), "%w%w%w%w", &reason_code,
                 &DebugID, &OSInfo1, &OSInfo2);
                                        /* Extract reason code from buffer. */
  reason_code &= 0xFFFF;        /* Strip away direction bit, OSInfo and     */
                                /* DebugInfo fields.  Will want to do some  */
                                /* sort of validation on this later.        */
  
  switch(reason_code)
  {

  case CL_WriteC:   /* Write a character to the terminal. */
                    /* byte data -> word status           */
    {
#ifdef DEBUG
      int c = (int)(*buffp);
      printf("CL_WriteC: [%02x]>%c<", c, isprint(c) ? c : '.');
#endif
      stateptr->hostif->writec(stateptr->hostif->hostosarg, (int)(*buffp));
      DevSW_FreePacket(packet);
      return msgsend(CI_CLIB,"%w%w%w%w%w", CL_WriteC|HtoT,
                    DebugID, OSInfo1, OSInfo2, NoError);
    }

  case CL_Write0:  /* Write a null terminated string to the terminal. */
    {
      unpack_message(buffp, "%w", &len);
      DebugCheckNullTermString("CL_Write0", TRUE, len, buffp+4);
      stateptr->hostif->write(stateptr->hostif->hostosarg,
                              (char *) buffp+4, len);
      DevSW_FreePacket(packet);
      return msgsend(CI_CLIB, "%w%w%w%w%w", CL_Write0|HtoT, DebugID, 
                    OSInfo1, OSInfo2, NoError);
    }

  case CL_ReadC:   /* Read a byte from the terminal */
    {
      DebugPrintF(("CL_ReadC: "));
      DevSW_FreePacket(packet);

      character = stateptr->hostif->readc(stateptr->hostif->hostosarg);
      DebugPrintF(("\nCL_ReadC returning [%02x]>%c<\n", character,
                   isprint(character) ? character : '.'));

      return msgsend(CI_CLIB, "%w%w%w%w%w%b", CL_ReadC|HtoT,
                    DebugID, OSInfo1, OSInfo2, NoError, character);
    }

  case CL_System:  /* Pass NULL terminated string to the hosts command 
                    * interpreter. As it is nULL terminated we dont need
                    * the length
                    */
    {
      unpack_message(buffp, "%w", &len);
      DebugCheckNullTermString("CL_System", TRUE, len, buffp+4);

      err = system((char *)buffp+4); /* Use the string in the buffer */
      stateptr->last_errno = errno;
      DebugCheckErr("system", TRUE, err, stateptr->last_errno);

      err = msgsend(CI_CLIB, "%w%w%w%w%w%w", CL_System|HtoT,
                    DebugID, OSInfo1, OSInfo2, NoError, err);
      DevSW_FreePacket(packet);
      return err;
    }

  case CL_GetCmdLine:  /* Returns the command line used to call the program */
    {
      /* Note: we reuse the packet here, this may not always be desirable */
      /* /* TODO: Use long buffers if possible */
      DebugPrintF(("CL_GetCmdLine: \"%s\"\n", *(stateptr->CommandLine)));

      if (buffhead!=NULL) {
        len = strlen(*(stateptr->CommandLine));
        if (len > Armsd_BufferSize-24) len = Armsd_BufferSize-24; 
        packet->pk_length = len + msgbuild(BUFFERDATA(buffhead),
                                           "%w%w%w%w%w%w", CL_GetCmdLine|HtoT,
                                           DebugID, OSInfo1, OSInfo2,
                                           NoError, len);
        strncpy((char *) BUFFERDATA(buffhead)+24,*(stateptr->CommandLine),
                len);
        
        Adp_ChannelWrite(CI_CLIB, packet);/* Send message. */
        return 0;
      }
      else return -1;
    }

  case CL_Clock:   /* Return the number of centiseconds since the support */
                   /* code started executing */
    {
      time_t retTime = time(NULL);
      if (retTime == (time_t)-1)
             stateptr->last_errno = errno;
      else
             retTime *=100;

      DebugPrintF(("CL_Clock: %lu\n", retTime));
      DebugCheckErr("time", TRUE, (retTime == (time_t)-1),
                    stateptr->last_errno);

      DevSW_FreePacket(packet);
      return msgsend(CI_CLIB, "%w%w%w%w%w%w",CL_Clock|HtoT,
                         DebugID, OSInfo1, OSInfo2, NoError, retTime);
    }

  case CL_Time:    /* return time, in seconds since the start of 1970 */
    {
      time_t retTime = time(NULL);
      if (retTime == (time_t)-1)
              stateptr->last_errno = errno;

      DebugPrintF(("CL_Time: %lu\n", retTime));
      DebugCheckErr("time", TRUE, (retTime == (time_t)-1),
                    stateptr->last_errno);

      DevSW_FreePacket(packet);
      return msgsend(CI_CLIB,"%w%w%w%w%w%w",CL_Time|HtoT,
                         DebugID, OSInfo1, OSInfo2, NoError, retTime);
    }

  case CL_Remove:  /* delete named in the null terminated string */
    {
      /* Removing an open file will cause problems but once again
       * its not our problem, likely result is a tangled FileTable */
      /* As the filename is passed with a null terminator we can use it
       * straight out of the buffer without copying it.*/

      unpack_message(buffp, "%w", &len);
      DebugCheckNullTermString("CL_Remove", TRUE, len, buffp+4);

      err=remove((char *)buffp+4);
      stateptr->last_errno = errno;
      DevSW_FreePacket(packet);
      DebugCheckErr("remove", TRUE, err, stateptr->last_errno);

      return msgsend(CI_CLIB, "%w%w%w%w%w", CL_Remove|HtoT,
                     DebugID, OSInfo1, OSInfo2, err?-1:NoError);
    }

  case CL_Rename:  /* rename file */
    {
      /* Rename(word nbytes, bytes oname, word nbytes, bytes nname)
      * return(byte status)
      */
      unsigned int len2;

      unpack_message(buffp, "%w", &len);
      DebugCheckNullTermString("CL_Rename", FALSE, len, buffp+4);
      unpack_message(buffp+5+len, "%w", &len2);
      DebugCheckNullTermString("to", TRUE, len2, buffp+9+len);

      /* Both names are passed with null terminators so we can use them
       * directly from the buffer. */
      err = rename((char *)buffp+4, (char *)buffp+9+len);
      stateptr->last_errno = errno;
      DebugCheckErr("rename", TRUE, err, stateptr->last_errno);
      DevSW_FreePacket(packet);

      return msgsend(CI_CLIB, "%w%w%w%w%w",  CL_Rename|HtoT,
                     DebugID, OSInfo1, OSInfo2, (err==0)? NoError : -1);
    }
  
  case CL_Open:    /* open the file */
    {
      /* Open(word nbytes, bytes name, byte mode)
      * return(word handle)
      */
      unpack_message(buffp, "%w", &len);
      /* get the open mode */
      unpack_message((buffp)+4+len+1, "%w", &mode);
      DebugCheckNullTermString("CL_Open", FALSE, len, buffp+4);
      DebugPrintF(("mode: %d\n", mode));

      /* do some checking on the file first? */
      /* check if its a tty */
      if (strcmp((char *)buffp+4, ":tt")==0 && (mode==0||mode==1)) {
        /* opening tty "r" */
        fhreal = stdin;
        stateptr->last_errno = errno;
        DebugPrintF(("\tstdin "));
      }
      else if (strcmp((char *)buffp+4, ":tt")== 0 && (mode==4||mode==5)) {
        /* opening tty "w" */
        fhreal = stdout;
        stateptr->last_errno = errno;
        DebugPrintF(("\tstdout "));
      }
      else
      {
        fhreal = fopen((char *)buffp+4, fmode[mode&0xFF]);
        stateptr->last_errno = errno;
        DebugCheckNonNull("fopen", FALSE, fhreal, stateptr->last_errno);
      }
      DevSW_FreePacket(packet);

      c = NONHANDLE;
      if (fhreal != NULL) {
        /* update filetable */
        for (c=3; c < HSYS_FOPEN_MAX; c++) {
          /* allow for stdin, stdout, stderr (!!! WHY? MJG) */
          if (stateptr->OSptr->FileTable[c] == NULL) {
            stateptr->OSptr->FileTable[c]= fhreal;
            stateptr->OSptr->FileFlags[c]= mode & 1;
            DebugPrintF(("fh: %d\n", c));
            break;
          }
          else if (c == HSYS_FOPEN_MAX) {
          /* no filehandles free */
          DebugPrintF(("no free fh: %d\n", c));
          stateptr->last_errno = EMFILE;
          }
        }
      }
      else {
        /*        c = NULL;*/
        DebugPrintF(("error fh: %d\n", c));
      }
      (void) msgsend(CI_CLIB, "%w%w%w%w%w",  CL_Open|HtoT,
                     DebugID, OSInfo1, OSInfo2, c);