bcachefs-tools/linux/string.c

/*
 *  linux/lib/string.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 */

/*
 * stupid library routines.. The optimized versions should generally be found
 * as inline code in <asm-xx/string.h>
 *
 * These are buggy as well..
 *
 * * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de>
 * -  Added strsep() which will replace strtok() soon (because strsep() is
 *    reentrant and should be faster). Use only strsep() in new code, please.
 *
 * * Sat Feb 09 2002, Jason Thomas <jason@topic.com.au>,
 *                    Matthew Hawkins <matt@mh.dropbear.id.au>
 * -  Kissed strtok() goodbye
 */

#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <string.h>

#include <linux/bug.h>
#include <linux/compiler.h>
#include <linux/string.h>

static char *skip_spaces(const char *str)
{
	while (isspace(*str))
		++str;
	return (char *)str;
}

char *strim(char *s)
{
	size_t size;
	char *end;

	size = strlen(s);
	if (!size)
		return s;

	end = s + size - 1;
	while (end >= s && isspace(*end))
		end--;
	*(end + 1) = '\0';

	return skip_spaces(s);
}

size_t strlcpy(char *dest, const char *src, size_t size)
{
	size_t ret = strlen(src);

	if (size) {
		size_t len = (ret >= size) ? size - 1 : ret;
		memcpy(dest, src, len);
		dest[len] = '\0';
	}
	return ret;
}

ssize_t strscpy(char *dest, const char *src, size_t count)
{
	long res = 0;

	if (count == 0 || WARN_ON_ONCE(count > INT_MAX))
		return -E2BIG;

	while (count) {
		char c;

		c = src[res];
		dest[res] = c;
		if (!c)
			return res;
		res++;
		count--;
	}

	/* Hit buffer length without finding a NUL; force NUL-termination. */
	if (res)
		dest[res-1] = '\0';

	return -E2BIG;
}

void memzero_explicit(void *s, size_t count)
{
	memset(s, 0, count);
	barrier_data(s);
}

int match_string(const char * const *array, size_t n, const char *string)
{
	int index;
	const char *item;

	for (index = 0; index < n; index++) {
		item = array[index];
		if (!item)
			break;
		if (!strcmp(item, string))
			return index;
	}

	return -EINVAL;
}

void *memscan(void *addr, int c, size_t size)
{
	unsigned char *p = addr;

	while (size) {
		if (*p == (unsigned char)c)
			return (void *)p;
		p++;
		size--;
	}
  	return (void *)p;
}