projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 1bd0b214 BJ |
1 | /* Copyright (c) 1979 Regents of the University of California */ |
| 2 | #include <stdio.h> | |
| 3 | _filbuf(iop) | |
| 4 | register struct _iobuf *iop; | |
| 5 | { | |
| 6 | static char smallbuf[_NFILE]; | |
| 7 | register n; | |
| 8 | char *malloc(); | |
| 9 | ||
| 10 | if ((iop->_flag&_IOREAD) == 0) | |
| 11 | _error("Reading bad file\n"); | |
| 12 | if (iop->_flag&_IOSTRG) | |
| 13 | return(-1); | |
| 14 | tryagain: | |
| 15 | if (iop->_base==NULL) { | |
| 16 | if (iop->_flag&_IONBF) { | |
| 17 | iop->_base = &smallbuf[fileno(iop)]; | |
| 18 | goto tryagain; | |
| 19 | } | |
| 20 | if ((iop->_base = malloc(BUFSIZ)) == NULL) { | |
| 21 | iop->_flag |= _IONBF; | |
| 22 | goto tryagain; | |
| 23 | } | |
| 24 | iop->_flag |= _IOMYBUF; | |
| 25 | } | |
| 26 | if((iop->_flag & _IODIRT) && !(iop->_flag & _IONBF) && (iop->_flag & _IOWRT)) { | |
| 27 | if (iop->_delta) | |
| 28 | if (lseek(iop->_file,(long) -iop->_delta, 1) < 0) { | |
| 29 | _error("Seek error in filbuf\n"); | |
| 30 | iop->_flag |= _IOERR; | |
| 31 | } | |
| 32 | if( 0 < (n = iop->_ptr - iop->_base)) | |
| 33 | if( n != write(iop->_file, iop->_base, n) ) | |
| 34 | iop->_flag |= _IOERR; | |
| 35 | iop->_flag &= ~_IODIRT; | |
| 36 | } | |
| 37 | iop->_ptr = iop->_base; | |
| 38 | iop->_cnt = read(fileno(iop), iop->_ptr, iop->_flag&_IONBF?1:BUFSIZ); | |
| 39 | iop->_delta = iop->_cnt; | |
| 40 | if (--iop->_cnt < 0) { | |
| 41 | if (iop->_cnt == -1) | |
| 42 | iop->_flag |= _IOEOF; | |
| 43 | else | |
| 44 | iop->_flag |= _IOERR; | |
| 45 | iop->_cnt = 0; | |
| 46 | return(-1); | |
| 47 | } | |
| 48 | return(*iop->_ptr++&0377); | |
| 49 | } |