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1.1 ! nbrk 1: /*-
! 2: * Copyright (c) 1990, 1993
! 3: * The Regents of the University of California. All rights reserved.
! 4: *
! 5: * This code is derived from software contributed to Berkeley by
! 6: * Chris Torek.
! 7: *
! 8: * Redistribution and use in source and binary forms, with or without
! 9: * modification, are permitted provided that the following conditions
! 10: * are met:
! 11: * 1. Redistributions of source code must retain the above copyright
! 12: * notice, this list of conditions and the following disclaimer.
! 13: * 2. Redistributions in binary form must reproduce the above copyright
! 14: * notice, this list of conditions and the following disclaimer in the
! 15: * documentation and/or other materials provided with the distribution.
! 16: * 3. Neither the name of the University nor the names of its contributors
! 17: * may be used to endorse or promote products derived from this software
! 18: * without specific prior written permission.
! 19: *
! 20: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 21: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 22: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 23: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 24: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 25: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 26: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 27: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 28: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 29: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 30: * SUCH DAMAGE.
! 31: */
! 32:
! 33: #include <stdio.h>
! 34: #include <string.h>
! 35: #include "local.h"
! 36: #include "fvwrite.h"
! 37:
! 38: /*
! 39: * Write some memory regions. Return zero on success, EOF on error.
! 40: *
! 41: * This routine is large and unsightly, but most of the ugliness due
! 42: * to the three different kinds of output buffering is handled here.
! 43: */
! 44: int
! 45: __sfvwrite(fp, uio)
! 46: FILE *fp;
! 47: struct __suio *uio;
! 48: {
! 49: size_t len;
! 50: char *p;
! 51: struct __siov *iov;
! 52: int w, s;
! 53: char *nl;
! 54: int nlknown, nldist;
! 55:
! 56: if ((len = uio->uio_resid) == 0)
! 57: return (0);
! 58: /* make sure we can write */
! 59: if (cantwrite(fp))
! 60: return (EOF);
! 61:
! 62: #define MIN(a, b) ((a) < (b) ? (a) : (b))
! 63: #define COPY(n) (void)memcpy((void *)fp->_p, (void *)p, (size_t)(n))
! 64:
! 65: iov = uio->uio_iov;
! 66: p = iov->iov_base;
! 67: len = iov->iov_len;
! 68: iov++;
! 69: #define GETIOV(extra_work) \
! 70: while (len == 0) { \
! 71: extra_work; \
! 72: p = iov->iov_base; \
! 73: len = iov->iov_len; \
! 74: iov++; \
! 75: }
! 76: if (fp->_flags & __SNBF) {
! 77: /*
! 78: * Unbuffered: write up to BUFSIZ bytes at a time.
! 79: */
! 80: do {
! 81: GETIOV(;);
! 82: w = __swrite(fp, p, MIN(len, BUFSIZ));
! 83: if (w <= 0)
! 84: goto err;
! 85: p += w;
! 86: len -= w;
! 87: } while ((uio->uio_resid -= w) != 0);
! 88: } else if ((fp->_flags & __SLBF) == 0) {
! 89: /*
! 90: * Fully buffered: fill partially full buffer, if any,
! 91: * and then flush. If there is no partial buffer, write
! 92: * one _bf._size byte chunk directly (without copying).
! 93: *
! 94: * String output is a special case: write as many bytes
! 95: * as fit, but pretend we wrote everything. This makes
! 96: * snprintf() return the number of bytes needed, rather
! 97: * than the number used, and avoids its write function
! 98: * (so that the write function can be invalid).
! 99: */
! 100: do {
! 101: GETIOV(;);
! 102: w = fp->_w;
! 103: if (fp->_flags & __SSTR) {
! 104: if (len < w)
! 105: w = len;
! 106: COPY(w); /* copy MIN(fp->_w,len), */
! 107: fp->_w -= w;
! 108: fp->_p += w;
! 109: w = len; /* but pretend copied all */
! 110: } else if (fp->_p > fp->_bf._base && len > w) {
! 111: /* fill and flush */
! 112: COPY(w);
! 113: /* fp->_w -= w; */ /* unneeded */
! 114: fp->_p += w;
! 115: if (fflush(fp))
! 116: goto err;
! 117: } else if (len >= (w = fp->_bf._size)) {
! 118: /* write directly */
! 119: w = __swrite(fp, p, w);
! 120: if (w <= 0)
! 121: goto err;
! 122: } else {
! 123: /* fill and done */
! 124: w = len;
! 125: COPY(w);
! 126: fp->_w -= w;
! 127: fp->_p += w;
! 128: }
! 129: p += w;
! 130: len -= w;
! 131: } while ((uio->uio_resid -= w) != 0);
! 132: } else {
! 133: /*
! 134: * Line buffered: like fully buffered, but we
! 135: * must check for newlines. Compute the distance
! 136: * to the first newline (including the newline),
! 137: * or `infinity' if there is none, then pretend
! 138: * that the amount to write is MIN(len,nldist).
! 139: */
! 140: nlknown = 0;
! 141: nldist = 0; /* XXX just to keep gcc happy */
! 142: do {
! 143: GETIOV(nlknown = 0);
! 144: if (!nlknown) {
! 145: nl = memchr((void *)p, '\n', len);
! 146: nldist = nl ? nl + 1 - p : len + 1;
! 147: nlknown = 1;
! 148: }
! 149: s = MIN(len, nldist);
! 150: w = fp->_w + fp->_bf._size;
! 151: if (fp->_p > fp->_bf._base && s > w) {
! 152: COPY(w);
! 153: /* fp->_w -= w; */
! 154: fp->_p += w;
! 155: if (fflush(fp))
! 156: goto err;
! 157: } else if (s >= (w = fp->_bf._size)) {
! 158: w = __swrite(fp, p, w);
! 159: if (w <= 0)
! 160: goto err;
! 161: } else {
! 162: w = s;
! 163: COPY(w);
! 164: fp->_w -= w;
! 165: fp->_p += w;
! 166: }
! 167: if ((nldist -= w) == 0) {
! 168: /* copied the newline: flush and forget */
! 169: if (fflush(fp))
! 170: goto err;
! 171: nlknown = 0;
! 172: }
! 173: p += w;
! 174: len -= w;
! 175: } while ((uio->uio_resid -= w) != 0);
! 176: }
! 177: return (0);
! 178:
! 179: err:
! 180: fp->_flags |= __SERR;
! 181: return (EOF);
! 182: }