/*
 *
 * honggfuzz - utilities
 * -----------------------------------------
 *
 * Author: Robert Swiecki <swiecki@google.com>
 *
 * Copyright 2010-2015 by Google Inc. All Rights Reserved.
 *
 * Licensed 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.
 *
 */

#include "common.h"
#include "util.h"

#include <fcntl.h>
#include <inttypes.h>
#include <math.h>
#include <pthread.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#include <ctype.h>

#include "files.h"
#include "log.h"

void *util_Malloc(size_t sz)
{
    void *p = malloc(sz);
    if (p == NULL) {
        LOG_F("malloc(size='%zu')", sz);
    }
    return p;
}

void *util_Calloc(size_t sz)
{
    void *p = util_Malloc(sz);
    memset(p, '\0', sz);
    return p;
}

extern void *util_Realloc(void *ptr, size_t sz)
{
    void *ret = realloc(ptr, sz);
    if (ret == NULL) {
        PLOG_W("realloc(%p, %zu)", ptr, sz);
        free(ptr);
        return NULL;
    }
    return ret;
}

void *util_MMap(size_t sz)
{
    void *p = mmap(NULL, sz, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE | MAP_NORESERVE, -1, 0);
    if (p == MAP_FAILED) {
        LOG_F("mmap(size='%zu')", sz);
    }
    return p;
}

char *util_StrDup(const char *s)
{
    char *ret = strdup(s);
    if (ret == NULL) {
        LOG_F("strdup(size=%zu)", strlen(s));
    }
    return ret;
}

static __thread pthread_once_t rndThreadOnce = PTHREAD_ONCE_INIT;
static __thread uint64_t rndX;

/* MMIX LCG PRNG */
static const uint64_t a = 6364136223846793005ULL;
static const uint64_t c = 1442695040888963407ULL;

static void util_rndInitThread(void)
{
    int fd = open("/dev/urandom", O_RDONLY | O_CLOEXEC);
    if (fd == -1) {
        PLOG_F("Couldn't open /dev/urandom for reading");
    }
    defer {
        close(fd);
    };

    if (files_readFromFd(fd, (uint8_t *) & rndX, sizeof(rndX)) != sizeof(rndX)) {
        PLOG_F("Couldn't read '%zu' bytes from /dev/urandom", sizeof(rndX));
    }
}

uint64_t util_rnd64(void)
{
    pthread_once(&rndThreadOnce, util_rndInitThread);
    rndX = a * rndX + c;
    return rndX;
}

uint64_t util_rndGet(uint64_t min, uint64_t max)
{
    if (min > max) {
        LOG_F("min:%" PRIu64 " > max:%" PRIu64, min, max);
    }

    return ((util_rnd64() % (max - min + 1)) + min);
}

void util_rndBuf(uint8_t * buf, size_t sz)
{
    if (sz == 0) {
        return;
    }
    pthread_once(&rndThreadOnce, util_rndInitThread);
    for (size_t i = 0; i < sz; i++) {
        rndX = a * rndX + c;
        buf[i] = (uint8_t) (rndX >> 15);
    }
}

/*
 * Function has variable length stack size, although already we know it's invoked
 * with relatively small sizes (max is _HF_REPORT_SIZE), thus safe to silent warning.
 */
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wframe-larger-than="
int util_vssnprintf(char *str, size_t size, const char *format, va_list ap)
{
    char buf1[size];
    char buf2[size];

    strncpy(buf1, str, size);

    vsnprintf(buf2, size, format, ap);

    return snprintf(str, size, "%s%s", buf1, buf2);
}

int util_ssnprintf(char *str, size_t size, const char *format, ...)
{
    char buf1[size];
    char buf2[size];

    snprintf(buf1, sizeof(buf1), "%s", str);

    va_list args;
    va_start(args, format);
    vsnprintf(buf2, size, format, args);
    va_end(args);

    return snprintf(str, size, "%s%s", buf1, buf2);
}

#pragma GCC diagnostic pop      /* EOF diagnostic ignored "-Wstack-usage=" */

void util_getLocalTime(const char *fmt, char *buf, size_t len, time_t tm)
{
    struct tm ltime;
    localtime_r(&tm, &ltime);
    if (strftime(buf, len, fmt, &ltime) < 1) {
        snprintf(buf, len, "[date fetch error]");
    }
}

void util_nullifyStdio(void)
{
    int fd = open("/dev/null", O_RDWR);

    if (fd == -1) {
        PLOG_E("Couldn't open '/dev/null'");
        return;
    }

    dup2(fd, 0);
    dup2(fd, 1);
    dup2(fd, 2);

    if (fd > 2) {
        close(fd);
    }
}

bool util_redirectStdin(const char *inputFile)
{
    int fd = open(inputFile, O_RDONLY);

    if (fd == -1) {
        PLOG_W("Couldn't open '%s'", inputFile);
        return false;
    }

    dup2(fd, 0);
    if (fd != 0) {
        close(fd);
    }

    return true;
}

/*
 * This is not a cryptographically secure hash
 */
uint64_t util_hash(const char *buf, size_t len)
{
    uint64_t ret = 0;

    for (size_t i = 0; i < len; i++) {
        ret += buf[i];
        ret += (ret << 10);
        ret ^= (ret >> 6);
    }

    return ret;
}

int64_t util_timeNowMillis(void)
{
    struct timeval tv;
    if (gettimeofday(&tv, NULL) == -1) {
        PLOG_F("gettimeofday()");
    }

    return (((int64_t) tv.tv_sec * 1000LL) + ((int64_t) tv.tv_usec / 1000LL));
}

uint64_t util_getUINT32(const uint8_t * buf)
{
    uint32_t r;
    memcpy(&r, buf, sizeof(r));
    return (uint64_t) r;
}

uint64_t util_getUINT64(const uint8_t * buf)
{
    uint64_t r;
    memcpy(&r, buf, sizeof(r));
    return r;
}

void util_mutexLock(pthread_mutex_t * mutex, const char *func, int line)
{
    if (pthread_mutex_lock(mutex)) {
        PLOG_F("%s():%d pthread_mutex_lock(%p)", func, line, (void *)mutex);
    }
}

void util_mutexUnlock(pthread_mutex_t * mutex, const char *func, int line)
{
    if (pthread_mutex_unlock(mutex)) {
        PLOG_F("%s():%d pthread_mutex_unlock(%p)", func, line, (void *)mutex);
    }
}

int64_t fastArray64Search(uint64_t * array, size_t arraySz, uint64_t key)
{
    size_t low = 0;
    size_t high = arraySz - 1;
    size_t mid;

    while (array[high] != array[low] && key >= array[low] && key <= array[high]) {
        mid = low + (key - array[low]) * ((high - low) / (array[high] - array[low]));

        if (array[mid] < key) {
            low = mid + 1;
        } else if (key < array[mid]) {
            high = mid - 1;
        } else {
            return mid;
        }
    }

    if (key == array[low]) {
        return low;
    } else {
        return -1;
    }
}

bool util_isANumber(const char *s)
{
    if (!isdigit(s[0])) {
        return false;
    }
    for (int i = 0; s[i]; s++) {
        if (!isdigit(s[i]) && s[i] != 'x') {
            return false;
        }
    }
    return true;
}

size_t util_decodeCString(char *s)
{
    size_t len = strlen(s);
    size_t o = 0;
    for (size_t i = 0; s[i] != '\0' && i < len; i++, o++) {
        switch (s[i]) {
        case '\\':{
                i++;
                switch (s[i]) {
                case 'a':
                    s[o] = '\a';
                    break;
                case 'r':
                    s[o] = '\r';
                    break;
                case 'n':
                    s[o] = '\n';
                    break;
                case 't':
                    s[o] = '\t';
                    break;
                case '0':
                    s[o] = '\0';
                    break;
                case 'x':{
                        /* Yup, this can overflow */
                        char hex[] = { s[i + 1], s[i + 2], 0 };
                        s[o] = strtoul(hex, NULL, 16);
                        i += 2;
                        break;
                    }
                default:
                    s[o] = ' ';
                    break;
                }
                break;
            }
        default:{
                s[o] = s[i];
                break;
            }
        }
    }
    s[o] = '\0';
    return o;
}

/* ISO 3309 CRC-64 Poly table */
static const uint64_t util_CRC64ISOPoly[] = {
    0x0000000000000000ULL, 0x01B0000000000000ULL, 0x0360000000000000ULL, 0x02D0000000000000ULL,
    0x06C0000000000000ULL, 0x0770000000000000ULL, 0x05A0000000000000ULL, 0x0410000000000000ULL,
    0x0D80000000000000ULL, 0x0C30000000000000ULL, 0x0EE0000000000000ULL, 0x0F50000000000000ULL,
    0x0B40000000000000ULL, 0x0AF0000000000000ULL, 0x0820000000000000ULL, 0x0990000000000000ULL,
    0x1B00000000000000ULL, 0x1AB0000000000000ULL, 0x1860000000000000ULL, 0x19D0000000000000ULL,
    0x1DC0000000000000ULL, 0x1C70000000000000ULL, 0x1EA0000000000000ULL, 0x1F10000000000000ULL,
    0x1680000000000000ULL, 0x1730000000000000ULL, 0x15E0000000000000ULL, 0x1450000000000000ULL,
    0x1040000000000000ULL, 0x11F0000000000000ULL, 0x1320000000000000ULL, 0x1290000000000000ULL,
    0x3600000000000000ULL, 0x37B0000000000000ULL, 0x3560000000000000ULL, 0x34D0000000000000ULL,
    0x30C0000000000000ULL, 0x3170000000000000ULL, 0x33A0000000000000ULL, 0x3210000000000000ULL,
    0x3B80000000000000ULL, 0x3A30000000000000ULL, 0x38E0000000000000ULL, 0x3950000000000000ULL,
    0x3D40000000000000ULL, 0x3CF0000000000000ULL, 0x3E20000000000000ULL, 0x3F90000000000000ULL,
    0x2D00000000000000ULL, 0x2CB0000000000000ULL, 0x2E60000000000000ULL, 0x2FD0000000000000ULL,
    0x2BC0000000000000ULL, 0x2A70000000000000ULL, 0x28A0000000000000ULL, 0x2910000000000000ULL,
    0x2080000000000000ULL, 0x2130000000000000ULL, 0x23E0000000000000ULL, 0x2250000000000000ULL,
    0x2640000000000000ULL, 0x27F0000000000000ULL, 0x2520000000000000ULL, 0x2490000000000000ULL,
    0x6C00000000000000ULL, 0x6DB0000000000000ULL, 0x6F60000000000000ULL, 0x6ED0000000000000ULL,
    0x6AC0000000000000ULL, 0x6B70000000000000ULL, 0x69A0000000000000ULL, 0x6810000000000000ULL,
    0x6180000000000000ULL, 0x6030000000000000ULL, 0x62E0000000000000ULL, 0x6350000000000000ULL,
    0x6740000000000000ULL, 0x66F0000000000000ULL, 0x6420000000000000ULL, 0x6590000000000000ULL,
    0x7700000000000000ULL, 0x76B0000000000000ULL, 0x7460000000000000ULL, 0x75D0000000000000ULL,
    0x71C0000000000000ULL, 0x7070000000000000ULL, 0x72A0000000000000ULL, 0x7310000000000000ULL,
    0x7A80000000000000ULL, 0x7B30000000000000ULL, 0x79E0000000000000ULL, 0x7850000000000000ULL,
    0x7C40000000000000ULL, 0x7DF0000000000000ULL, 0x7F20000000000000ULL, 0x7E90000000000000ULL,
    0x5A00000000000000ULL, 0x5BB0000000000000ULL, 0x5960000000000000ULL, 0x58D0000000000000ULL,
    0x5CC0000000000000ULL, 0x5D70000000000000ULL, 0x5FA0000000000000ULL, 0x5E10000000000000ULL,
    0x5780000000000000ULL, 0x5630000000000000ULL, 0x54E0000000000000ULL, 0x5550000000000000ULL,
    0x5140000000000000ULL, 0x50F0000000000000ULL, 0x5220000000000000ULL, 0x5390000000000000ULL,
    0x4100000000000000ULL, 0x40B0000000000000ULL, 0x4260000000000000ULL, 0x43D0000000000000ULL,
    0x47C0000000000000ULL, 0x4670000000000000ULL, 0x44A0000000000000ULL, 0x4510000000000000ULL,
    0x4C80000000000000ULL, 0x4D30000000000000ULL, 0x4FE0000000000000ULL, 0x4E50000000000000ULL,
    0x4A40000000000000ULL, 0x4BF0000000000000ULL, 0x4920000000000000ULL, 0x4890000000000000ULL,
    0xD800000000000000ULL, 0xD9B0000000000000ULL, 0xDB60000000000000ULL, 0xDAD0000000000000ULL,
    0xDEC0000000000000ULL, 0xDF70000000000000ULL, 0xDDA0000000000000ULL, 0xDC10000000000000ULL,
    0xD580000000000000ULL, 0xD430000000000000ULL, 0xD6E0000000000000ULL, 0xD750000000000000ULL,
    0xD340000000000000ULL, 0xD2F0000000000000ULL, 0xD020000000000000ULL, 0xD190000000000000ULL,
    0xC300000000000000ULL, 0xC2B0000000000000ULL, 0xC060000000000000ULL, 0xC1D0000000000000ULL,
    0xC5C0000000000000ULL, 0xC470000000000000ULL, 0xC6A0000000000000ULL, 0xC710000000000000ULL,
    0xCE80000000000000ULL, 0xCF30000000000000ULL, 0xCDE0000000000000ULL, 0xCC50000000000000ULL,
    0xC840000000000000ULL, 0xC9F0000000000000ULL, 0xCB20000000000000ULL, 0xCA90000000000000ULL,
    0xEE00000000000000ULL, 0xEFB0000000000000ULL, 0xED60000000000000ULL, 0xECD0000000000000ULL,
    0xE8C0000000000000ULL, 0xE970000000000000ULL, 0xEBA0000000000000ULL, 0xEA10000000000000ULL,
    0xE380000000000000ULL, 0xE230000000000000ULL, 0xE0E0000000000000ULL, 0xE150000000000000ULL,
    0xE540000000000000ULL, 0xE4F0000000000000ULL, 0xE620000000000000ULL, 0xE790000000000000ULL,
    0xF500000000000000ULL, 0xF4B0000000000000ULL, 0xF660000000000000ULL, 0xF7D0000000000000ULL,
    0xF3C0000000000000ULL, 0xF270000000000000ULL, 0xF0A0000000000000ULL, 0xF110000000000000ULL,
    0xF880000000000000ULL, 0xF930000000000000ULL, 0xFBE0000000000000ULL, 0xFA50000000000000ULL,
    0xFE40000000000000ULL, 0xFFF0000000000000ULL, 0xFD20000000000000ULL, 0xFC90000000000000ULL,
    0xB400000000000000ULL, 0xB5B0000000000000ULL, 0xB760000000000000ULL, 0xB6D0000000000000ULL,
    0xB2C0000000000000ULL, 0xB370000000000000ULL, 0xB1A0000000000000ULL, 0xB010000000000000ULL,
    0xB980000000000000ULL, 0xB830000000000000ULL, 0xBAE0000000000000ULL, 0xBB50000000000000ULL,
    0xBF40000000000000ULL, 0xBEF0000000000000ULL, 0xBC20000000000000ULL, 0xBD90000000000000ULL,
    0xAF00000000000000ULL, 0xAEB0000000000000ULL, 0xAC60000000000000ULL, 0xADD0000000000000ULL,
    0xA9C0000000000000ULL, 0xA870000000000000ULL, 0xAAA0000000000000ULL, 0xAB10000000000000ULL,
    0xA280000000000000ULL, 0xA330000000000000ULL, 0xA1E0000000000000ULL, 0xA050000000000000ULL,
    0xA440000000000000ULL, 0xA5F0000000000000ULL, 0xA720000000000000ULL, 0xA690000000000000ULL,
    0x8200000000000000ULL, 0x83B0000000000000ULL, 0x8160000000000000ULL, 0x80D0000000000000ULL,
    0x84C0000000000000ULL, 0x8570000000000000ULL, 0x87A0000000000000ULL, 0x8610000000000000ULL,
    0x8F80000000000000ULL, 0x8E30000000000000ULL, 0x8CE0000000000000ULL, 0x8D50000000000000ULL,
    0x8940000000000000ULL, 0x88F0000000000000ULL, 0x8A20000000000000ULL, 0x8B90000000000000ULL,
    0x9900000000000000ULL, 0x98B0000000000000ULL, 0x9A60000000000000ULL, 0x9BD0000000000000ULL,
    0x9FC0000000000000ULL, 0x9E70000000000000ULL, 0x9CA0000000000000ULL, 0x9D10000000000000ULL,
    0x9480000000000000ULL, 0x9530000000000000ULL, 0x97E0000000000000ULL, 0x9650000000000000ULL,
    0x9240000000000000ULL, 0x93F0000000000000ULL, 0x9120000000000000ULL, 0x9090000000000000ULL,
};

uint64_t util_CRC64(uint8_t * buf, size_t len)
{
    uint64_t res = 0ULL;

    for (size_t i = 0; i < len; i++) {
        res = util_CRC64ISOPoly[(uint8_t) res ^ buf[i]] ^ (res >> 8);
    }

    return res;
}