manual: document snprintf truncation better
[glibc.git] / stdio-common / Xprintf_buffer_puts_1.c
blobc6b088b40afdd738bb934b5f4e0b4d217c332a4d
1 /* String write function for struct __*printf_buffer. Generic version.
2 Copyright (C) 2022-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
19 #include <assert.h>
20 #include <string.h>
22 void
23 Xprintf (buffer_puts_1) (struct Xprintf_buffer *buf, const CHAR_T *s)
25 if (__glibc_unlikely (Xprintf_buffer_has_failed (buf)))
26 return;
28 while (*s != 0)
30 if (buf->write_ptr == buf->write_end && !Xprintf_buffer_flush (buf))
31 return;
32 assert (buf->write_ptr != buf->write_end);
33 size_t to_copy = STRNLEN (s, buf->write_end - buf->write_ptr);
34 MEMCPY (buf->write_ptr, s, to_copy);
35 buf->write_ptr += to_copy;
36 s += to_copy;