C语言dump一块内存

void dump_buffer(const char * buffer, int size)
{
    if (size > 0 && buffer != NULL) {
        int   i = 0;
        char *dump_buffer = (char *)malloc(size * 5);
        for (i = 0; i < size; i++) {
            unsigned char c = buffer[i];
            sprintf(dump_buffer + i * 5, "%02x/%c ", c, isprint(c) ? c : '.');
        }
        dump_buffer[size * 5 - 1]='\0';
        printf("dumpbuffer size=%d, buffer=[%s]", size, dump_buffer);
        free(dump_buffer);
    }
}