nuttx/libs/libc/string/lib_strrchr.c

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/****************************************************************************
* libs/libc/string/lib_strrchr.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <string.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/* The strrchr() function returns a pointer to the last
* occurrence of the character c in the string s.
*/
FAR char *strrchr(FAR const char *s, int c)
{
if (s)
{
Merged in paimonen/nuttx/pullreq_libc_libnx_updates (pull request #757) Pullreq libc libnx updates * NuttX: make strerror() return 'Success' for 0 * NuttX: fix strrchr() so that it considers null terminator as part of string From strrchr(3) man page: "The terminating null byte is considered part of the string, so that if c is specified as '\0', these functions return a pointer to the terminator." * NuttX: mm_free(): Add DEBUGASSERT()'s to catch memory corruption early. It's easier to find the source when asserts fail already when freeing an overflowed buffer, than if the corruption is only detected on next malloc(). * MM_FILL_ALLOCATIONS: Add debug option to fill all mallocs() This is helpful for detecting uninitialized variables, especially in C++ code. I seem to be forgetting to initialize member variables and then they just get random values.. * NuttX: nxtk_bitmapwindow: Fix warning message when bitmap is fully off-screen. * nxfonts_getfont: Avoid unnecessary warnings for other whitespace chars also. * NuttX: Fix kerning of 'I' in Sans17x22 font The I character was running together with some other characters, e.g. in sequence "IMI". * NXMU: Revalidate window pointer for mouse events. NXMU caches the previous window pointer so that further mouse events can be sent to the same window. However, if the window is destroyed while mouse button is held down, the pointer may become invalid and cause a crash. This patch revalidates the pointer before using it. Approved-by: GregoryN <gnutt@nuttx.org>
2018-11-12 16:36:35 +01:00
const char *p = &s[strlen(s)];
for (; p >= s; p--)
{
if (*p == c)
{
return (FAR char *)p;
}
}
}
return NULL;
}