neesenk

static char ffslut32[] = {
	32,  1, 23,  2, 29, 24, 14,  3, 30, 27, 25, 18, 20, 15, 10,  4,
	31, 22, 28, 13, 26, 17, 19,  9, 21, 12, 16,  8, 11,  7,  6,  5
};

static char ffslut64[] = {
	64,  1, 48,  2, 57, 49, 28,  3, 61, 58, 50, 42, 38, 29, 17,  4,
	62, 55, 59, 36, 53, 51, 43, 22, 45, 39, 33, 30, 24, 18, 12,  5,
	63, 47, 56, 27, 60, 41, 37, 16, 54, 35, 52, 21, 44, 32, 23, 11,

neesenk

/* 0000000: 0000 0000 0000 0000 0000 0000 0000 0000  ................ */
void hexdump(const char *buff, int blen)
{
	static char hexmap[] = "0123456789abcdef";
	int offset, len, count, hexoff;
	unsigned char str[58], c;
	str[57] = 0, str[40] = ' ';
	for (offset = 0, len = 16; offset < blen; offset += 16) {
		if (blen - offset < 16) {
			len = blen - offset;

neesenk

#ifndef __DYNAMINC_ARRAY_H__
#define __DYNAMINC_ARRAY_H__

#include <string.h>
#include <stdlib.h>
#include <assert.h>

#ifdef __cplusplus
extern "C" {
#endif

neesenk

#include "darray.h"
int change_path(D_ARRAY *path, const char *change, size_t ch_len)
{
#define IS_DIR_END(path) ((path)->array[(path)->len - 1] == '/')
#define PUT_DRI(path, dir, dir_len) do {			\
	if ((path)->len == 0 || !IS_DIR_END(path))	\
		dynamic_array_put(path, "/", 1);		\
	dynamic_array_put(path, dir, dir_len);			\
} while (0);
	/* 最多可能需要添加额外两个'/' */

neesenk

/* from http://www.isthe.com/chongo/tech/comp/fnv/index.html */
uint32_t fnv(const void *buf, size_t len, uint32_t seed)
{
	const uint8_t *bp, *be;
	uint32_t h = seed ^ len;
	for (bp = (const uint8_t *)buf, be = bp + len; bp < be; bp++) {
		h ^= (uint32_t)(*bp);
		/* h *= 0x01000193 */
		h += (h << 1) + (h << 4) + (h << 7) + (h << 8) + (h << 24);
	}

neesenk

char *strtrim(char *str)
{
	size_t len;
	char *pb;
	for (pb = str; isspace(*pb); pb++); /* isspace(0) == 0 */
	for (len = strlen(pb); len > 0 && isspace(pb[len - 1]); len--);
	if (pb > str && len > 0)
		memmove(str, pb, len);
	str[len] = 0;
	return str;

neesenk

/* 输出[0..n-1]的一个随机子集m */
void randselect(int *a, int m, int n)
{
	while (m > 0) {
		if (random() % n-- < m)
			a[--m] = n;
	}
}

neesenk

const char *getprogname_by_pid(int pid)
{
	static char path[1024];
	static char sympath[32];
	int len = 0;
	snprintf(sympath, sizeof(sympath), "/proc/%d/exe", pid);

	len = readlink(sympath, path, sizeof(path) - 1);
	if (len < 0)
		return NULL;

neesenk

/* 编译时断言, cond为编译时常量 */
#define BUILD_ASSERT(cond) do { (void) sizeof(char [1 - 2*!(cond)]); } while(0)
#define EXPR_BUILD_ASSERT(cond) (sizeof(char [1 - 2*!(cond)]) - 1)

/* 数据类型的对齐方式 == __alignof__(t) */
#define ALIGNOF(t) ((char *)(&((struct { char c; t _h; } *)0)->_h) - (char *)0)

#define container_of(ptr, type, member)				\
	((type *)((char *)(ptr) - (size_t)(&((type *)0)->member)))

neesenk

#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

uint32_t hashint10(uint32_t h)
{
	h ^= (h >> 20) ^ (h >> 12);
	return h ^ (h >> 7) ^ (h >> 4);
}