--- /dev/null
+.\" Copyright (c) 1990, 1991, 1993
+.\" The Regents of the University of California. All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\" notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\" notice, this list of conditions and the following disclaimer in the
+.\" documentation and/or other materials provided with the distribution.
+.\" 3. Neither the name of the University nor the names of its contributors
+.\" may be used to endorse or promote products derived from this software
+.\" without specific prior written permission.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" @(#)fgetln.3 8.3 (Berkeley) 4/19/94
+.\" $FreeBSD$
+.\"
+.Dd July 16, 2004
+.Dt FGETWLN 3
+.Os
+.Sh NAME
+.Nm fgetwln
+.Nd get a line of wide characters from a stream
+.Sh LIBRARY
+.ds str-Lb-libbsd Utility functions from BSD systems (libbsd, \-lbsd)
+.Lb libbsd
+.Sh SYNOPSIS
+.In stdio.h
+.In bsd/wchar.h
+.Ft wchar_t *
+.Fn fgetwln "FILE * restrict stream" "size_t * restrict len"
+.Sh DESCRIPTION
+The
+.Fn fgetwln
+function
+returns a pointer to the next line from the stream referenced by
+.Fa stream .
+This line is
+.Em not
+a standard wide character string as it does not end with a terminating
+null wide character.
+The length of the line, including the final newline,
+is stored in the memory location to which
+.Fa len
+points.
+(Note, however, that if the line is the last
+in a file that does not end in a newline,
+the returned text will not contain a newline.)
+.Sh RETURN VALUES
+Upon successful completion a pointer is returned;
+this pointer becomes invalid after the next
+.Tn I/O
+operation on
+.Fa stream
+(whether successful or not)
+or as soon as the stream is closed.
+Otherwise,
+.Dv NULL
+is returned.
+The
+.Fn fgetwln
+function
+does not distinguish between end-of-file and error; the routines
+.Xr feof 3
+and
+.Xr ferror 3
+must be used
+to determine which occurred.
+If an error occurs, the global variable
+.Va errno
+is set to indicate the error.
+The end-of-file condition is remembered, even on a terminal, and all
+subsequent attempts to read will return
+.Dv NULL
+until the condition is
+cleared with
+.Xr clearerr 3 .
+.Pp
+The text to which the returned pointer points may be modified,
+provided that no changes are made beyond the returned size.
+These changes are lost as soon as the pointer becomes invalid.
+.Sh ERRORS
+.Bl -tag -width Er
+.It Bq Er EBADF
+The argument
+.Fa stream
+is not a stream open for reading.
+.El
+.Pp
+The
+.Fn fgetwln
+function
+may also fail and set
+.Va errno
+for any of the errors specified for the routines
+.Xr mbrtowc 3 ,
+.Xr realloc 3 ,
+or
+.Xr read 2 .
+.Sh SEE ALSO
+.Xr ferror 3 ,
+.Xr fgetln 3 ,
+.Xr fgetws 3 ,
+.Xr fopen 3
--- /dev/null
+/*
+ * Copyright © 2012 Guillem Jover <guillem@hadrons.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <wchar.h>
+
+struct filewbuf {
+ FILE *fp;
+ wchar_t *wbuf;
+ size_t len;
+};
+
+#define FILEWBUF_INIT_LEN 128
+#define FILEWBUF_POOL_ITEMS 32
+
+static struct filewbuf fb_pool[FILEWBUF_POOL_ITEMS];
+static int fb_pool_cur;
+
+wchar_t *
+fgetwln(FILE *stream, size_t *lenp)
+{
+ struct filewbuf *fb;
+ wint_t wc;
+ size_t wused = 0;
+
+ /* Try to diminish the possibility of several fgetwln() calls being
+ * used on different streams, by using a pool of buffers per file. */
+ fb = &fb_pool[fb_pool_cur];
+ if (fb->fp != stream && fb->fp != NULL) {
+ fb_pool_cur++;
+ fb_pool_cur %= FILEWBUF_POOL_ITEMS;
+ fb = &fb_pool[fb_pool_cur];
+ }
+ fb->fp = stream;
+
+ while ((wc = fgetwc(stream)) != WEOF) {
+ if (!fb->len || wused > fb->len) {
+ wchar_t *wp;
+
+ if (fb->len)
+ fb->len *= 2;
+ else
+ fb->len = FILEWBUF_INIT_LEN;
+
+ wp = realloc(fb->wbuf, fb->len * sizeof(wchar_t));
+ if (wp == NULL) {
+ wused = 0;
+ break;
+ }
+ fb->wbuf = wp;
+ }
+
+ fb->wbuf[wused++] = wc;
+
+ if (wc == L'\n')
+ break;
+ }
+
+ *lenp = wused;
+ return wused ? fb->wbuf : NULL;
+}