1: # include   "ctlmod.h"
   2: # include   "pipes.h"
   3: # include   <sccs.h>
   4: 
   5: SCCSID(@(#)proc_err.c	8.1	12/31/84)
   6: 
   7: /*
   8: **  PROC_ERR -- Process error message
   9: **
  10: **	This routine processes an error.  It searches back through
  11: **	the chain of contexts until it finds one that is willing to
  12: **	process this error, or it finds that it must transfer the
  13: **	error to another process to handle it.
  14: **
  15: **	It also unwinds the tree of
  16: **	activations.  It leaves us in the context that processes
  17: **	the error, or the state that should be reading the
  18: **	input pipe.
  19: **
  20: **	The local error handling function returns zero if the
  21: **	error should be ignored, anything else otherwise.
  22: **
  23: **	Parameters:
  24: **		pc -- error parameter count.
  25: **		pv -- error parameter vector.
  26: **		ppb -- a pointer to a pipe block to use in
  27: **			sending this error.
  28: **
  29: **	Returns:
  30: **		none.
  31: **
  32: **	Side Effects:
  33: **		Unwinds the list of activations.
  34: **		The input pipe can be changed under certain
  35: **			circumstances.
  36: **
  37: **	Trace Flags:
  38: **		6.8 - 6.15
  39: */
  40: 
  41: 
  42: proc_err(ppb, pc, pv)
  43: pb_t    *ppb;
  44: int pc;
  45: PARM    pv[];
  46: {
  47:     register struct fn_def  *f;
  48:     extern char     *Proc_name;
  49:     register int        i;
  50:     register ctx_t      *ctx;
  51:     extern pb_t     *MonPpb;
  52: 
  53: # ifdef xCTR2
  54:     if (tTf(6, 8))
  55:         lprintf("proc_err: new = %d\n", Ctx.ctx_new);
  56: # endif
  57:     pb_prime(ppb, PB_ERR);
  58: 
  59:     /*
  60: 	**  Scan back on the list of context dependencies.
  61: 	**	If we come to someone who can process this message,
  62: 	**	we go ahead and do it.  We also take this
  63: 	**	opportunity to unwind the context list & call the
  64: 	**	cleanup functions.
  65: 	*/
  66: 
  67:     for (ctx = &Ctx; ctx != NULL; ctx = ctx->ctx_link)
  68:     {
  69:         Proc_name = ctx->ctx_name;
  70:         f = ctx->ctx_fn;
  71: # ifdef xCTR2
  72:         if (tTf(6, 9))
  73:             lprintf("proc_err: unwinding %s: errfn=%x, ppb=%x, link=%x, resp=%d, fn=%x\n",
  74:                 Proc_name, ctx->ctx_errfn, ctx->ctx_ppb,
  75:                 ctx->ctx_link, ctx->ctx_resp, f);
  76: # endif
  77: 
  78:         /*  Do the actual error processing. */
  79:         ppb->pb_proc = ctx->ctx_resp;
  80:         if (ctx->ctx_errfn != NULL)
  81:             i = (*ctx->ctx_errfn)(pc, pv);
  82:         else
  83:             i = -1;
  84: 
  85: # ifdef xCTR2
  86:         if (tTf(6, 11))
  87:             lprintf("proc_err: errcode %d\n", i);
  88: # endif
  89:         if (i == 0)
  90:             break;
  91:         else if (i > 0)
  92:         {
  93:             /* turn into nonfatal error */
  94:             ppb->pb_stat |= PB_INFO;
  95:             ppb->pb_proc = PB_FRONT;
  96:         }
  97:         else
  98:         {
  99:             /* call the cleanup function */
 100:             if (f != NULL && f->fn_active > 0)
 101:                 (*f->fn_cleanup)(1);
 102:         }
 103: 
 104:         /* arrange to leave if parent not in this process */
 105:         if (ppb->pb_proc != Cm.cm_myproc)
 106:         {
 107:             send_off(ppb, pc, pv);
 108:             pb_flush(ppb);
 109: 
 110:             /* throw away dead contexts and exit */
 111:             break;
 112:         }
 113:     }
 114:     if (ctx == NULL)
 115:         syserr("proc_err: no parent");
 116: 
 117: # ifdef xCTR3
 118:     if (tTf(6, 12))
 119:     {
 120:         lprintf("proc_err: cleanup: ctx=%x, ->_link=%x, MonPpb = ", ctx, ctx->ctx_link);
 121:         pb_dump(MonPpb, TRUE);
 122:     }
 123: # endif
 124:     /* pop contexts down to ctx and exit */
 125:     ctx = ctx->ctx_link;
 126:     while (Ctx.ctx_link != ctx)
 127:     {
 128:         if (Ctx.ctx_link == NULL)
 129:             syserr("proc_err: underflow");
 130:         Ctx.ctx_new = TRUE;
 131:         resetp();
 132:     }
 133: 
 134:     /*
 135: 	**  Flush input pipe.
 136: 	**	THIS CODE IS ONLY NEEDED TO MAKE READMON WORK, AND
 137: 	**	SHOULD BE REMOVED WHEN READMON GOES AWAY!!
 138: 	*/
 139: 
 140:     if (ctx == NULL)
 141:     {
 142:         Cm.cm_input = Cm.cm_rinput;
 143:         while (!bitset(PB_EOF, MonPpb->pb_stat))
 144:             pb_read(MonPpb);
 145:         MonPpb->pb_st = PB_UNKNOWN;
 146:     }
 147: 
 148:     longjmp(Ctx.ctx_jbuf, 1);
 149: }

Defined functions

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