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- #ident "$Id: line_input.c,v 1.5 2004/12/20 22:55:48 hpa Exp $"
- /* ----------------------------------------------------------------------- *
- *
- * Copyright 2004 H. Peter Anvin - All Rights Reserved
- *
- * Permission is hereby granted, free of charge, to any person
- * obtaining a copy of this software and associated documentation
- * files (the "Software"), to deal in the Software without
- * restriction, including without limitation the rights to use,
- * copy, modify, merge, publish, distribute, sublicense, and/or
- * sell copies of the Software, and to permit persons to whom
- * the Software is furnished to do so, subject to the following
- * conditions:
- *
- * The above copyright notice and this permission notice shall
- * be included in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
- * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
- * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
- * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
- * OTHER DEALINGS IN THE SOFTWARE.
- *
- * ----------------------------------------------------------------------- */
-
- /*
- * line_input.c
- *
- * Line-oriented input discupline
- */
-
- #include "file.h"
- #include <errno.h>
-
- ssize_t __line_input(struct file_info *fp, char *buf, size_t bufsize,
- ssize_t (*get_char)(struct file_info *, void *, size_t))
- {
- size_t n = 0;
- char ch;
- int rv;
- ssize_t (* const Write)(struct file_info *, const void *, size_t) =
- fp->oop->write;
-
- for(;;) {
- rv = get_char(fp, &ch, 1);
-
- if ( rv != 1 )
- continue;
-
- switch ( ch ) {
- case '\n': /* Ignore incoming linefeed */
- break;
-
- case '\r':
- *buf = '\n';
- Write(fp, "\n", 1);
- return n+1;
-
- case '\b':
- if ( n > 0 ) {
- n--; buf--;
- Write(fp, "\b \b", 3);
- }
- break;
-
- case '\x15': /* Ctrl-U */
- while ( n ) {
- n--; buf--;
- Write(fp, "\b \b", 3);
- }
- break;
-
- default:
- if ( n < bufsize-1 ) {
- *buf = ch;
- Write(fp, buf, 1);
- n++;
- buf++;
- }
- break;
- }
- }
- }
-
-