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Diffstat (limited to 'src/lib/libast/sfio/sfpkrd.c')
-rw-r--r--src/lib/libast/sfio/sfpkrd.c325
1 files changed, 325 insertions, 0 deletions
diff --git a/src/lib/libast/sfio/sfpkrd.c b/src/lib/libast/sfio/sfpkrd.c
new file mode 100644
index 0000000..2572e6d
--- /dev/null
+++ b/src/lib/libast/sfio/sfpkrd.c
@@ -0,0 +1,325 @@
+/***********************************************************************
+* *
+* This software is part of the ast package *
+* Copyright (c) 1985-2012 AT&T Intellectual Property *
+* and is licensed under the *
+* Eclipse Public License, Version 1.0 *
+* by AT&T Intellectual Property *
+* *
+* A copy of the License is available at *
+* http://www.eclipse.org/org/documents/epl-v10.html *
+* (with md5 checksum b35adb5213ca9657e911e9befb180842) *
+* *
+* Information and Software Systems Research *
+* AT&T Research *
+* Florham Park NJ *
+* *
+* Glenn Fowler <gsf@research.att.com> *
+* David Korn <dgk@research.att.com> *
+* Phong Vo <kpv@research.att.com> *
+* *
+***********************************************************************/
+#include "sfhdr.h"
+#if !_PACKAGE_ast
+#ifndef FIONREAD
+#if _sys_ioctl
+#include <sys/ioctl.h>
+#endif
+#endif
+#endif
+
+/* Read/Peek a record from an unseekable device
+**
+** Written by Kiem-Phong Vo.
+*/
+
+#define STREAM_PEEK 001
+#define SOCKET_PEEK 002
+
+#if __STD_C
+ssize_t sfpkrd(int fd, Void_t* argbuf, size_t n, int rc, long tm, int action)
+#else
+ssize_t sfpkrd(fd, argbuf, n, rc, tm, action)
+int fd; /* file descriptor */
+Void_t* argbuf; /* buffer to read data */
+size_t n; /* buffer size */
+int rc; /* record character */
+long tm; /* time-out */
+int action; /* >0: peeking, if rc>=0, get action records,
+ <0: no peeking, if rc>=0, get -action records,
+ =0: no peeking, if rc>=0, must get a single record
+ */
+#endif
+{
+ reg ssize_t r;
+ reg int ntry, t;
+ reg char *buf = (char*)argbuf, *endbuf;
+
+ if(rc < 0 && tm < 0 && action <= 0)
+ return sysreadf(fd,buf,n);
+
+ t = (action > 0 || rc >= 0) ? (STREAM_PEEK|SOCKET_PEEK) : 0;
+#if !_stream_peek
+ t &= ~STREAM_PEEK;
+#endif
+#if !_socket_peek
+ t &= ~SOCKET_PEEK;
+#endif
+
+ for(ntry = 0; ntry < 2; ++ntry)
+ {
+ r = -1;
+#if _stream_peek
+ if((t&STREAM_PEEK) && (ntry == 1 || tm < 0) )
+ {
+#ifdef __sun
+ /*
+ * I_PEEK on stdin can hang rsh+ksh on solaris
+ * this kludge will have to do until sun^H^H^Horacle fixes I_PEEK/rsh
+ */
+ static int stream_peek;
+ if (stream_peek == 0) /* this will be done just once */
+ { char *e;
+ stream_peek = (
+ getenv("LOGNAME") == 0 &&
+ getenv("MAIL") == 0 &&
+ ((e = getenv("LANG")) == 0 || strcmp(e, "C") == 0) &&
+ ((e = getenv("PATH")) == 0 || strncmp(e, "/usr/bin:", 9) == 0)
+ ) ? -1 : 1;
+ }
+ if(stream_peek < 0)
+ t &= ~STREAM_PEEK;
+ else
+#endif
+ { struct strpeek pbuf;
+ pbuf.flags = 0;
+ pbuf.ctlbuf.maxlen = -1;
+ pbuf.ctlbuf.len = 0;
+ pbuf.ctlbuf.buf = NIL(char*);
+ pbuf.databuf.maxlen = n;
+ pbuf.databuf.buf = buf;
+ pbuf.databuf.len = 0;
+
+ if((r = ioctl(fd,I_PEEK,&pbuf)) < 0)
+ { if(errno == EINTR)
+ return -1;
+ t &= ~STREAM_PEEK;
+ }
+ else
+ { t &= ~SOCKET_PEEK;
+ if(r > 0 && (r = pbuf.databuf.len) <= 0)
+ { if(action <= 0) /* read past eof */
+ r = sysreadf(fd,buf,1);
+ return r;
+ }
+ if(r == 0)
+ r = -1;
+ else if(r > 0)
+ break;
+ }
+ }
+ }
+#endif /* stream_peek */
+
+ if(ntry == 1)
+ break;
+
+ /* poll or select to see if data is present. */
+ while(tm >= 0 || action > 0 ||
+ /* block until there is data before peeking again */
+ ((t&STREAM_PEEK) && rc >= 0) ||
+ /* let select be interrupted instead of recv which autoresumes */
+ (t&SOCKET_PEEK) )
+ { r = -2;
+#if _lib_poll
+ if(r == -2)
+ {
+ struct pollfd po;
+ po.fd = fd;
+ po.events = POLLIN;
+ po.revents = 0;
+
+ if((r = SFPOLL(&po,1,tm)) < 0)
+ { if(errno == EINTR)
+ return -1;
+ else if(errno == EAGAIN)
+ { errno = 0;
+ continue;
+ }
+ else r = -2;
+ }
+ else r = (po.revents&POLLIN) ? 1 : -1;
+ }
+#endif /*_lib_poll*/
+#if _lib_select
+ if(r == -2)
+ {
+#if _hpux_threads && vt_threaded
+#define fd_set int
+#endif
+ fd_set rd;
+ struct timeval tmb, *tmp;
+ FD_ZERO(&rd);
+ FD_SET(fd,&rd);
+ if(tm < 0)
+ tmp = NIL(struct timeval*);
+ else
+ { tmp = &tmb;
+ tmb.tv_sec = tm/SECOND;
+ tmb.tv_usec = (tm%SECOND)*SECOND;
+ }
+ r = select(fd+1,&rd,NIL(fd_set*),NIL(fd_set*),tmp);
+ if(r < 0)
+ { if(errno == EINTR)
+ return -1;
+ else if(errno == EAGAIN)
+ { errno = 0;
+ continue;
+ }
+ else r = -2;
+ }
+ else r = FD_ISSET(fd,&rd) ? 1 : -1;
+ }
+#endif /*_lib_select*/
+ if(r == -2)
+ {
+#if !_lib_poll && !_lib_select /* both poll and select can't be used */
+#ifdef FIONREAD /* quick and dirty check for availability */
+ long nsec = tm < 0 ? 0 : (tm+999)/1000;
+ while(nsec > 0 && r < 0)
+ { long avail = -1;
+ if((r = ioctl(fd,FIONREAD,&avail)) < 0)
+ { if(errno == EINTR)
+ return -1;
+ else if(errno == EAGAIN)
+ { errno = 0;
+ continue;
+ }
+ else /* ioctl failed completely */
+ { r = -2;
+ break;
+ }
+ }
+ else r = avail <= 0 ? -1 : (ssize_t)avail;
+
+ if(r < 0 && nsec-- > 0)
+ sleep(1);
+ }
+#endif
+#endif
+ }
+
+ if(r > 0) /* there is data now */
+ { if(action <= 0 && rc < 0)
+ return sysreadf(fd,buf,n);
+ else r = -1;
+ }
+ else if(tm >= 0) /* timeout exceeded */
+ return -1;
+ else r = -1;
+ break;
+ }
+
+#if _socket_peek
+ if(t&SOCKET_PEEK)
+ {
+#if __MACH__ && __APPLE__ /* check 10.4 recv(MSG_PEEK) bug that consumes pipe data */
+ static int recv_peek_pipe;
+ if (recv_peek_pipe == 0) /* this will be done just once */
+ { int fds[2], r;
+ char tst[2];
+
+ tst[0] = 'a'; tst[1] = 'z';
+
+ /* open a pipe and write to it */
+ recv_peek_pipe = 1;
+ if(recv_peek_pipe == 1 && pipe(fds) < 0)
+ recv_peek_pipe = -1;
+ if(recv_peek_pipe == 1 && write(fds[1], tst, 2) != 2)
+ recv_peek_pipe = -1;
+
+ /* try recv() to see if it gets anything */
+ tst[0] = tst[1] = 0;
+ if(recv_peek_pipe == 1 && (r = recv(fds[0], tst, 1, MSG_PEEK)) != 1)
+ recv_peek_pipe = -1;
+ if(recv_peek_pipe == 1 && tst[0] != 'a')
+ recv_peek_pipe = -1;
+
+ /* make sure that recv() did not consume data */
+ tst[0] = tst[1] = 0;
+ if(recv_peek_pipe == 1 && (r = recv(fds[0], tst, 2, MSG_PEEK)) != 2)
+ recv_peek_pipe = -1;
+ if(recv_peek_pipe == 1 && (tst[0] != 'a' || tst[1] != 'z') )
+ recv_peek_pipe = -1;
+
+ close(fds[0]);
+ close(fds[1]);
+ }
+
+ if(recv_peek_pipe < 0)
+ { struct stat st; /* recv should work on sockets */
+ if(fstat(fd, &st) < 0 || !S_ISSOCK(st.st_mode) )
+ { r = -1;
+ t &= ~SOCKET_PEEK;
+ }
+ }
+#endif
+ while((t&SOCKET_PEEK) && (r = recv(fd,(char*)buf,n,MSG_PEEK)) < 0)
+ { if(errno == EINTR)
+ return -1;
+ else if(errno == EAGAIN)
+ errno = 0;
+ else t &= ~SOCKET_PEEK;
+ }
+ if(r >= 0)
+ { t &= ~STREAM_PEEK;
+ if(r > 0)
+ break;
+ else /* read past eof */
+ { if(action <= 0)
+ r = sysreadf(fd,buf,1);
+ return r;
+ }
+ }
+ }
+#endif
+ }
+
+ if(r < 0)
+ { if(tm >= 0 || action > 0)
+ return -1;
+ else /* get here means: tm < 0 && action <= 0 && rc >= 0 */
+ { /* number of records read at a time */
+ if((action = action ? -action : 1) > (int)n)
+ action = n;
+ r = 0;
+ while((t = sysreadf(fd,buf,action)) > 0)
+ { r += t;
+ for(endbuf = buf+t; buf < endbuf;)
+ if(*buf++ == rc)
+ action -= 1;
+ if(action == 0 || (int)(n-r) < action)
+ break;
+ }
+ return r == 0 ? t : r;
+ }
+ }
+
+ /* successful peek, find the record end */
+ if(rc >= 0)
+ { reg char* sp;
+
+ t = action == 0 ? 1 : action < 0 ? -action : action;
+ for(endbuf = (sp = buf)+r; sp < endbuf; )
+ if(*sp++ == rc)
+ if((t -= 1) == 0)
+ break;
+ r = sp - buf;
+ }
+
+ /* advance */
+ if(action <= 0)
+ r = sysreadf(fd,buf,r);
+
+ return r;
+}
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