1*b30d1939SAndy Fiddaman /***********************************************************************
2*b30d1939SAndy Fiddaman * *
3*b30d1939SAndy Fiddaman * This software is part of the ast package *
4*b30d1939SAndy Fiddaman * Copyright (c) 1985-2011 AT&T Intellectual Property *
5*b30d1939SAndy Fiddaman * and is licensed under the *
6*b30d1939SAndy Fiddaman * Eclipse Public License, Version 1.0 *
7*b30d1939SAndy Fiddaman * by AT&T Intellectual Property *
8*b30d1939SAndy Fiddaman * *
9*b30d1939SAndy Fiddaman * A copy of the License is available at *
10*b30d1939SAndy Fiddaman * http://www.eclipse.org/org/documents/epl-v10.html *
11*b30d1939SAndy Fiddaman * (with md5 checksum b35adb5213ca9657e911e9befb180842) *
12*b30d1939SAndy Fiddaman * *
13*b30d1939SAndy Fiddaman * Information and Software Systems Research *
14*b30d1939SAndy Fiddaman * AT&T Research *
15*b30d1939SAndy Fiddaman * Florham Park NJ *
16*b30d1939SAndy Fiddaman * *
17*b30d1939SAndy Fiddaman * Glenn Fowler <gsf@research.att.com> *
18*b30d1939SAndy Fiddaman * David Korn <dgk@research.att.com> *
19*b30d1939SAndy Fiddaman * Phong Vo <kpv@research.att.com> *
20*b30d1939SAndy Fiddaman * *
21*b30d1939SAndy Fiddaman ***********************************************************************/
22*b30d1939SAndy Fiddaman #include "sfhdr.h"
23*b30d1939SAndy Fiddaman
24*b30d1939SAndy Fiddaman /* Function to handle io exceptions.
25*b30d1939SAndy Fiddaman ** Written by Kiem-Phong Vo
26*b30d1939SAndy Fiddaman */
27*b30d1939SAndy Fiddaman
28*b30d1939SAndy Fiddaman #if __STD_C
_sfexcept(Sfio_t * f,int type,ssize_t io,Sfdisc_t * disc)29*b30d1939SAndy Fiddaman int _sfexcept(Sfio_t* f, int type, ssize_t io, Sfdisc_t* disc)
30*b30d1939SAndy Fiddaman #else
31*b30d1939SAndy Fiddaman int _sfexcept(f,type,io,disc)
32*b30d1939SAndy Fiddaman Sfio_t* f; /* stream where the exception happened */
33*b30d1939SAndy Fiddaman int type; /* io type that was performed */
34*b30d1939SAndy Fiddaman ssize_t io; /* the io return value that indicated exception */
35*b30d1939SAndy Fiddaman Sfdisc_t* disc; /* discipline in use */
36*b30d1939SAndy Fiddaman #endif
37*b30d1939SAndy Fiddaman {
38*b30d1939SAndy Fiddaman reg int ev, local, lock;
39*b30d1939SAndy Fiddaman reg ssize_t size;
40*b30d1939SAndy Fiddaman reg uchar* data;
41*b30d1939SAndy Fiddaman SFMTXDECL(f); /* declare a local stream variable for multithreading */
42*b30d1939SAndy Fiddaman
43*b30d1939SAndy Fiddaman SFMTXENTER(f,-1);
44*b30d1939SAndy Fiddaman
45*b30d1939SAndy Fiddaman GETLOCAL(f,local);
46*b30d1939SAndy Fiddaman lock = f->mode&SF_LOCK;
47*b30d1939SAndy Fiddaman
48*b30d1939SAndy Fiddaman if(local && io <= 0)
49*b30d1939SAndy Fiddaman f->flags |= io < 0 ? SF_ERROR : SF_EOF;
50*b30d1939SAndy Fiddaman
51*b30d1939SAndy Fiddaman if(disc && disc->exceptf)
52*b30d1939SAndy Fiddaman { /* let the stream be generally accessible for this duration */
53*b30d1939SAndy Fiddaman if(local && lock)
54*b30d1939SAndy Fiddaman SFOPEN(f,0);
55*b30d1939SAndy Fiddaman
56*b30d1939SAndy Fiddaman /* so that exception handler knows what we are asking for */
57*b30d1939SAndy Fiddaman _Sfi = f->val = io;
58*b30d1939SAndy Fiddaman ev = (*(disc->exceptf))(f,type,&io,disc);
59*b30d1939SAndy Fiddaman
60*b30d1939SAndy Fiddaman /* relock if necessary */
61*b30d1939SAndy Fiddaman if(local && lock)
62*b30d1939SAndy Fiddaman SFLOCK(f,0);
63*b30d1939SAndy Fiddaman
64*b30d1939SAndy Fiddaman if(io > 0 && !(f->flags&SF_STRING) )
65*b30d1939SAndy Fiddaman SFMTXRETURN(f, ev);
66*b30d1939SAndy Fiddaman if(ev < 0)
67*b30d1939SAndy Fiddaman SFMTXRETURN(f, SF_EDONE);
68*b30d1939SAndy Fiddaman if(ev > 0)
69*b30d1939SAndy Fiddaman SFMTXRETURN(f, SF_EDISC);
70*b30d1939SAndy Fiddaman }
71*b30d1939SAndy Fiddaman
72*b30d1939SAndy Fiddaman if(f->flags&SF_STRING)
73*b30d1939SAndy Fiddaman { if(type == SF_READ)
74*b30d1939SAndy Fiddaman goto chk_stack;
75*b30d1939SAndy Fiddaman else if(type != SF_WRITE && type != SF_SEEK)
76*b30d1939SAndy Fiddaman SFMTXRETURN(f, SF_EDONE);
77*b30d1939SAndy Fiddaman if(local && io >= 0)
78*b30d1939SAndy Fiddaman { if(f->size >= 0 && !(f->flags&SF_MALLOC))
79*b30d1939SAndy Fiddaman goto chk_stack;
80*b30d1939SAndy Fiddaman /* extend buffer */
81*b30d1939SAndy Fiddaman if((size = f->size) < 0)
82*b30d1939SAndy Fiddaman size = 0;
83*b30d1939SAndy Fiddaman if((io -= size) <= 0)
84*b30d1939SAndy Fiddaman io = SF_GRAIN;
85*b30d1939SAndy Fiddaman size = ((size+io+SF_GRAIN-1)/SF_GRAIN)*SF_GRAIN;
86*b30d1939SAndy Fiddaman if(f->size > 0)
87*b30d1939SAndy Fiddaman data = (uchar*)realloc((char*)f->data,size);
88*b30d1939SAndy Fiddaman else data = (uchar*)malloc(size);
89*b30d1939SAndy Fiddaman if(!data)
90*b30d1939SAndy Fiddaman goto chk_stack;
91*b30d1939SAndy Fiddaman f->endb = data + size;
92*b30d1939SAndy Fiddaman f->next = data + (f->next - f->data);
93*b30d1939SAndy Fiddaman f->endr = f->endw = f->data = data;
94*b30d1939SAndy Fiddaman f->size = size;
95*b30d1939SAndy Fiddaman }
96*b30d1939SAndy Fiddaman SFMTXRETURN(f, SF_EDISC);
97*b30d1939SAndy Fiddaman }
98*b30d1939SAndy Fiddaman
99*b30d1939SAndy Fiddaman if(errno == EINTR)
100*b30d1939SAndy Fiddaman { if(_Sfexiting || (f->bits&SF_ENDING) || /* stop being a hero */
101*b30d1939SAndy Fiddaman (f->flags&SF_IOINTR) ) /* application requests to return */
102*b30d1939SAndy Fiddaman SFMTXRETURN(f, SF_EDONE);
103*b30d1939SAndy Fiddaman
104*b30d1939SAndy Fiddaman /* a normal interrupt, we can continue */
105*b30d1939SAndy Fiddaman errno = 0;
106*b30d1939SAndy Fiddaman f->flags &= ~(SF_EOF|SF_ERROR);
107*b30d1939SAndy Fiddaman SFMTXRETURN(f, SF_ECONT);
108*b30d1939SAndy Fiddaman }
109*b30d1939SAndy Fiddaman
110*b30d1939SAndy Fiddaman chk_stack:
111*b30d1939SAndy Fiddaman if(local && f->push &&
112*b30d1939SAndy Fiddaman ((type == SF_READ && f->next >= f->endb) ||
113*b30d1939SAndy Fiddaman (type == SF_WRITE && f->next <= f->data)))
114*b30d1939SAndy Fiddaman { /* pop the stack */
115*b30d1939SAndy Fiddaman reg Sfio_t *pf;
116*b30d1939SAndy Fiddaman
117*b30d1939SAndy Fiddaman if(lock)
118*b30d1939SAndy Fiddaman SFOPEN(f,0);
119*b30d1939SAndy Fiddaman
120*b30d1939SAndy Fiddaman /* pop and close */
121*b30d1939SAndy Fiddaman pf = (*_Sfstack)(f,NIL(Sfio_t*));
122*b30d1939SAndy Fiddaman if((ev = sfclose(pf)) < 0) /* can't close, restack */
123*b30d1939SAndy Fiddaman (*_Sfstack)(f,pf);
124*b30d1939SAndy Fiddaman
125*b30d1939SAndy Fiddaman if(lock)
126*b30d1939SAndy Fiddaman SFLOCK(f,0);
127*b30d1939SAndy Fiddaman
128*b30d1939SAndy Fiddaman ev = ev < 0 ? SF_EDONE : SF_ESTACK;
129*b30d1939SAndy Fiddaman }
130*b30d1939SAndy Fiddaman else ev = SF_EDONE;
131*b30d1939SAndy Fiddaman
132*b30d1939SAndy Fiddaman SFMTXRETURN(f, ev);
133*b30d1939SAndy Fiddaman }
134