stellar-stellar/src/hexdump/hexdump.cpp

#include "hexdump.h"

void hexdump_to_fd(int fd, uint32_t idx, const char *data, uint16_t len)
{
    uint16_t i = 0;
    uint16_t used = 0;
    uint16_t offset = 0;

#define LINE_LEN 80
    char line[LINE_LEN]; /* space needed 8+16*3+3+16 == 75 */
    while (offset < len)
    {
        used = snprintf(line, LINE_LEN, "%08X ", idx + offset);

        // hexdump
        for (i = 0; ((offset + i) < len) && (i < 16); i++)
        {
            if (i == 8)
            {
                used += snprintf(line + used, LINE_LEN - used, " ");
            }
            used += snprintf(line + used, LINE_LEN - used, " %02x", (data[offset + i] & 0xff));
        }

        // padding
        for (; i <= 16; i++)
        {
            if (i == 8)
            {
                used += snprintf(line + used, LINE_LEN - used, " ");
            }
            used += snprintf(line + used, LINE_LEN - used, "   ");
        }

        // ascii
        for (i = 0; (offset < len) && (i < 16); i++, offset++)
        {
            unsigned char c = data[offset];
            if ((c < ' ') || (c > '~'))
            {
                c = '.';
            }
            if (i == 8)
            {
                used += snprintf(line + used, LINE_LEN - used, " ");
            }
            used += snprintf(line + used, LINE_LEN - used, "%c", c);
        }
        dprintf(fd, "%s\n", line);
    }
}