nuttx/libs/libc/string/lib_ffsll.c
Xiang Xiao c32b683085 !compiler: drop CONFIG_HAVE_LONG_LONG and require long long support
Every compiler supported by NuttX provides the "long long" types,
so the CONFIG_HAVE_LONG_LONG indirection is no longer useful.
Remove the option from include/nuttx/compiler.h and treat
"long long" as unconditionally available across the OS.

In addition to deleting the guard itself, this commit unconditionally
enables the long-long flavored helpers that used to be gated behind
it:

  - libs/libc/fixedmath: drop the soft-emulated b32/ub32 routines
    in lib_fixedmath.c (-261 lines) and trim the matching
    prototypes, Make.defs and CMakeLists.txt entries; keep only
    the long-long backed implementations.
  - include/sys/endian.h, include/strings.h, libs/libc/string
    /lib_ffsll.c, lib_flsll.c: always expose the 64-bit byte-swap
    and ffsll/flsll variants.
  - libs/libm/libm/lib_llround{,f,l}.c: drop the empty stubs.
  - libs/libc/stdlib (atoll, llabs, lldiv, strtoll/ull, rand48,
    strtold), libs/libc/stream (libvsprintf, libvscanf,
    libbsprintf, ultoa_invert), libs/libc/misc (crc64, crc64emac),
    libs/libc/inttypes/strtoimax, libs/libc/lzf, libs/libc/libc.csv,
    libs/libc/string (memset, vikmemcpy): remove the
    #ifdef CONFIG_HAVE_LONG_LONG branches.
  - include/{stddef.h,stdlib.h,fixedmath.h,sys/epoll.h,cxx/cstdlib,
    nuttx/audio/audio.h,nuttx/crc64.h,nuttx/lib/math.h,
    nuttx/lib/math32.h,nuttx/lib/stdbit.h}: same guard cleanup.
  - drivers/note/note_driver.c, fs/spiffs/src/spiffs.h,
    sched/irq/irq_procfs.c: drop their local guards as well.
  - Documentation/applications/netutils/ntpclient/index.rst:
    refresh the documentation snippet.

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
2026-05-19 16:21:28 +08:00

67 lines
2.3 KiB
C

/****************************************************************************
* libs/libc/string/lib_ffsll.c
*
* SPDX-License-Identifier: Apache-2.0
*
* 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.
*
****************************************************************************/
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define NBITS (8 * sizeof(unsigned long long))
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: ffsll
*
* Description:
* The ffsll() function will find the first bit set (beginning with the
* least significant bit) in i, and return the index of that bit. Bits are
* numbered starting at one (the least significant bit).
*
* Returned Value:
* The ffsll() function will return the index of the first bit set. If j is
* 0, then ffsll() will return 0.
*
****************************************************************************/
int ffsll(long long j)
{
int ret = 0;
if (j != 0)
{
unsigned long long value = (unsigned long long)j;
int bitno;
for (bitno = 1; bitno <= NBITS; bitno++, value >>= 1)
{
if ((value & 1) != 0)
{
ret = bitno;
break;
}
}
}
return ret;
}