binarybuffer.c

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// SPDX-License-Identifier: GPL-2.0-or-later
 
/***************************************************************************
 *   Copyright (C) 2004, 2005 by Dominic Rath                              *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
 *   oyvind.harboe@zylin.com                                               *
 ***************************************************************************/
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#include "helper/replacements.h"
#include "log.h"
#include "binarybuffer.h"
 
static const unsigned char bit_reverse_table256[] = {
    0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
    0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, 0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
    0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
    0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
    0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
    0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
    0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, 0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
    0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE, 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
    0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
    0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
    0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, 0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
    0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
    0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
    0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, 0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
    0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
    0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
};
 
static const char hex_digits[] = {
    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
    'a', 'b', 'c', 'd', 'e', 'f'
};
 
void *buf_cpy(const void *from, void *_to, unsigned size)
{
    if (!from || !_to)
        return NULL;
 
    /* copy entire buffer */
    memcpy(_to, from, DIV_ROUND_UP(size, 8));
 
    /* mask out bits that don't belong to the buffer */
    unsigned trailing_bits = size % 8;
    if (trailing_bits) {
        uint8_t *to = _to;
        to[size / 8] &= (1 << trailing_bits) - 1;
    }
    return _to;
}
 
static bool buf_cmp_masked(uint8_t a, uint8_t b, uint8_t m)
{
    return (a & m) != (b & m);
}
static bool buf_cmp_trailing(uint8_t a, uint8_t b, uint8_t m, unsigned trailing)
{
    uint8_t mask = (1 << trailing) - 1;
    return buf_cmp_masked(a, b, mask & m);
}
 
bool buf_cmp(const void *_buf1, const void *_buf2, unsigned size)
{
    if (!_buf1 || !_buf2)
        return _buf1 != _buf2;
 
    unsigned last = size / 8;
    if (memcmp(_buf1, _buf2, last) != 0)
        return false;
 
    unsigned trailing = size % 8;
    if (!trailing)
        return false;
 
    const uint8_t *buf1 = _buf1, *buf2 = _buf2;
    return buf_cmp_trailing(buf1[last], buf2[last], 0xff, trailing);
}
 
bool buf_cmp_mask(const void *_buf1, const void *_buf2,
    const void *_mask, unsigned size)
{
    if (!_buf1 || !_buf2)
        return _buf1 != _buf2 || _buf1 != _mask;
 
    const uint8_t *buf1 = _buf1, *buf2 = _buf2, *mask = _mask;
    unsigned last = size / 8;
    for (unsigned i = 0; i < last; i++) {
        if (buf_cmp_masked(buf1[i], buf2[i], mask[i]))
            return true;
    }
    unsigned trailing = size % 8;
    if (!trailing)
        return false;
    return buf_cmp_trailing(buf1[last], buf2[last], mask[last], trailing);
}
 
 
void *buf_set_ones(void *_buf, unsigned size)
{
    uint8_t *buf = _buf;
    if (!buf)
        return NULL;
 
    memset(buf, 0xff, size / 8);
 
    unsigned trailing_bits = size % 8;
    if (trailing_bits)
        buf[size / 8] = (1 << trailing_bits) - 1;
 
    return buf;
}
 
void *buf_set_buf(const void *_src, unsigned src_start,
    void *_dst, unsigned dst_start, unsigned len)
{
    const uint8_t *src = _src;
    uint8_t *dst = _dst;
    unsigned i, sb, db, sq, dq, lb, lq;
 
    sb = src_start / 8;
    db = dst_start / 8;
    sq = src_start % 8;
    dq = dst_start % 8;
    lb = len / 8;
    lq = len % 8;
 
    src += sb;
    dst += db;
 
    /* check if both buffers are on byte boundary and
     * len is a multiple of 8bit so we can simple copy
     * the buffer */
    if ((sq == 0) && (dq == 0) &&  (lq == 0)) {
        for (i = 0; i < lb; i++)
            *dst++ = *src++;
        return _dst;
    }
 
    /* fallback to slow bit copy */
    for (i = 0; i < len; i++) {
        if (((*src >> (sq&7)) & 1) == 1)
            *dst |= 1 << (dq&7);
        else
            *dst &= ~(1 << (dq&7));
        if (sq++ == 7) {
            sq = 0;
            src++;
        }
        if (dq++ == 7) {
            dq = 0;
            dst++;
        }
    }
 
    return _dst;
}
 
uint32_t flip_u32(uint32_t value, unsigned int num)
{
    uint32_t c = (bit_reverse_table256[value & 0xff] << 24) |
        (bit_reverse_table256[(value >> 8) & 0xff] << 16) |
        (bit_reverse_table256[(value >> 16) & 0xff] << 8) |
        (bit_reverse_table256[(value >> 24) & 0xff]);
 
    if (num < 32)
        c = c >> (32 - num);
 
    return c;
}
 
static int ceil_f_to_u32(float x)
{
    if (x < 0)  /* return zero for negative numbers */
        return 0;
 
    uint32_t y = x; /* cut off fraction */
 
    if ((x - y) > 0.0)  /* if there was a fractional part, increase by one */
        y++;
 
    return y;
}
 
char *buf_to_hex_str(const void *_buf, unsigned buf_len)
{
    unsigned len_bytes = DIV_ROUND_UP(buf_len, 8);
    char *str = calloc(len_bytes * 2 + 1, 1);
 
    const uint8_t *buf = _buf;
    for (unsigned i = 0; i < len_bytes; i++) {
        uint8_t tmp = buf[len_bytes - i - 1];
        if ((i == 0) && (buf_len % 8))
            tmp &= (0xff >> (8 - (buf_len % 8)));
        str[2 * i] = hex_digits[tmp >> 4];
        str[2 * i + 1] = hex_digits[tmp & 0xf];
    }
 
    return str;
}
 
static void str_radix_guess(const char **_str, unsigned *_str_len,
    unsigned *_radix)
{
    unsigned radix = *_radix;
    if (radix != 0)
        return;
    const char *str = *_str;
    unsigned str_len = *_str_len;
    if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X')) {
        radix = 16;
        str += 2;
        str_len -= 2;
    } else if ((str[0] == '0') && (str_len != 1)) {
        radix = 8;
        str += 1;
        str_len -= 1;
    } else
        radix = 10;
    *_str = str;
    *_str_len = str_len;
    *_radix = radix;
}
 
int str_to_buf(const char *str, unsigned str_len,
    void *_buf, unsigned buf_len, unsigned radix)
{
    str_radix_guess(&str, &str_len, &radix);
 
    float factor;
    if (radix == 16)
        factor = 0.5;   /* log(16) / log(256) = 0.5 */
    else if (radix == 10)
        factor = 0.41524;   /* log(10) / log(256) = 0.41524 */
    else if (radix == 8)
        factor = 0.375; /* log(8) / log(256) = 0.375 */
    else
        return 0;
 
    /* copy to zero-terminated buffer */
    char *charbuf = strndup(str, str_len);
 
    /* number of digits in base-256 notation */
    unsigned b256_len = ceil_f_to_u32(str_len * factor);
    uint8_t *b256_buf = calloc(b256_len, 1);
 
    /* go through zero terminated buffer
     * input digits (ASCII) */
    unsigned i;
    for (i = 0; charbuf[i]; i++) {
        uint32_t tmp = charbuf[i];
        if ((tmp >= '0') && (tmp <= '9'))
            tmp = (tmp - '0');
        else if ((tmp >= 'a') && (tmp <= 'f'))
            tmp = (tmp - 'a' + 10);
        else if ((tmp >= 'A') && (tmp <= 'F'))
            tmp = (tmp - 'A' + 10);
        else
            continue;   /* skip characters other than [0-9,a-f,A-F] */
 
        if (tmp >= radix)
            continue;   /* skip digits invalid for the current radix */
 
        /* base-256 digits */
        for (unsigned j = 0; j < b256_len; j++) {
            tmp += (uint32_t)b256_buf[j] * radix;
            b256_buf[j] = (uint8_t)(tmp & 0xFF);
            tmp >>= 8;
        }
 
    }
 
    uint8_t *buf = _buf;
    for (unsigned j = 0; j < DIV_ROUND_UP(buf_len, 8); j++) {
        if (j < b256_len)
            buf[j] = b256_buf[j];
        else
            buf[j] = 0;
    }
 
    /* mask out bits that don't belong to the buffer */
    if (buf_len % 8)
        buf[(buf_len / 8)] &= 0xff >> (8 - (buf_len % 8));
 
    free(b256_buf);
    free(charbuf);
 
    return i;
}
 
void bit_copy_queue_init(struct bit_copy_queue *q)
{
    INIT_LIST_HEAD(&q->list);
}
 
int bit_copy_queued(struct bit_copy_queue *q, uint8_t *dst, unsigned dst_offset, const uint8_t *src,
    unsigned src_offset, unsigned bit_count)
{
    struct bit_copy_queue_entry *qe = malloc(sizeof(*qe));
    if (!qe)
        return ERROR_FAIL;
 
    qe->dst = dst;
    qe->dst_offset = dst_offset;
    qe->src = src;
    qe->src_offset = src_offset;
    qe->bit_count = bit_count;
    list_add_tail(&qe->list, &q->list);
 
    return ERROR_OK;
}
 
void bit_copy_execute(struct bit_copy_queue *q)
{
    struct bit_copy_queue_entry *qe;
    struct bit_copy_queue_entry *tmp;
    list_for_each_entry_safe(qe, tmp, &q->list, list) {
        bit_copy(qe->dst, qe->dst_offset, qe->src, qe->src_offset, qe->bit_count);
        list_del(&qe->list);
        free(qe);
    }
}
 
void bit_copy_discard(struct bit_copy_queue *q)
{
    struct bit_copy_queue_entry *qe;
    struct bit_copy_queue_entry *tmp;
    list_for_each_entry_safe(qe, tmp, &q->list, list) {
        list_del(&qe->list);
        free(qe);
    }
}
 
size_t unhexify(uint8_t *bin, const char *hex, size_t count)
{
    size_t i;
    char tmp;
 
    if (!bin || !hex)
        return 0;
 
    memset(bin, 0, count);
 
    for (i = 0; i < 2 * count; i++) {
        if (hex[i] >= 'a' && hex[i] <= 'f')
            tmp = hex[i] - 'a' + 10;
        else if (hex[i] >= 'A' && hex[i] <= 'F')
            tmp = hex[i] - 'A' + 10;
        else if (hex[i] >= '0' && hex[i] <= '9')
            tmp = hex[i] - '0';
        else
            return i / 2;
 
        bin[i / 2] |= tmp << (4 * ((i + 1) % 2));
    }
 
    return i / 2;
}
 
size_t hexify(char *hex, const uint8_t *bin, size_t count, size_t length)
{
    size_t i;
    uint8_t tmp;
 
    if (!length)
        return 0;
 
    for (i = 0; i < length - 1 && i < 2 * count; i++) {
        tmp = (bin[i / 2] >> (4 * ((i + 1) % 2))) & 0x0f;
        hex[i] = hex_digits[tmp];
    }
 
    hex[i] = 0;
 
    return i;
}
 
void buffer_shr(void *_buf, unsigned buf_len, unsigned count)
{
    unsigned i;
    unsigned char *buf = _buf;
    unsigned bytes_to_remove;
    unsigned shift;
 
    bytes_to_remove = count / 8;
    shift = count - (bytes_to_remove * 8);
 
    for (i = 0; i < (buf_len - 1); i++)
        buf[i] = (buf[i] >> shift) | ((buf[i+1] << (8 - shift)) & 0xff);
 
    buf[(buf_len - 1)] = buf[(buf_len - 1)] >> shift;
 
    if (bytes_to_remove) {
        memmove(buf, &buf[bytes_to_remove], buf_len - bytes_to_remove);
        memset(&buf[buf_len - bytes_to_remove], 0, bytes_to_remove);
    }
}