C++ read_word函数代码示例

/* Seek zip->fp to compressed data
   return:
	==0 success
	<0 error
*/
int seekcompresszip(ZIP* zip, struct zipent* ent) {
	char buf[ZIPNAME];
	long offset;

	if (!zip->fp) {
		if (!revivezip(zip))
			return -1;
	}

	if (osd_fseek(zip->fp, ent->offset_lcl_hdr_frm_frst_disk, SEEK_SET)!=0) {
		errormsg ("Seeking to header", ERROR_CORRUPT, zip->zip);
		return -1;
	}

	if (osd_fread(zip->fp, buf, ZIPNAME)!=ZIPNAME) {
		errormsg ("Reading header", ERROR_CORRUPT, zip->zip);
		return -1;
	}

	{
		UINT16 filename_length = read_word (buf+ZIPFNLN);
		UINT16 extra_field_length = read_word (buf+ZIPXTRALN);

		/* calculate offset to data and osd_fseek() there */
		offset = ent->offset_lcl_hdr_frm_frst_disk + ZIPNAME + filename_length + extra_field_length;

		if (osd_fseek(zip->fp, offset, SEEK_SET) != 0) {
			errormsg ("Seeking to compressed data", ERROR_CORRUPT, zip->zip);
			return -1;
		}

	}

	return 0;
}

void vbe_biosfn_restore_video_state(uint16_t ES, uint16_t BX)
{
    uint16_t    enable, i;

    enable = read_word(ES, BX);
    BX += 2;

    if (!(enable & VBE_DISPI_ENABLED)) {
        outw(VBE_DISPI_IOPORT_INDEX,VBE_DISPI_INDEX_ENABLE);
        outw(VBE_DISPI_IOPORT_DATA, enable);
    } else {
        outw(VBE_DISPI_IOPORT_INDEX, VBE_DISPI_INDEX_XRES);
        outw(VBE_DISPI_IOPORT_DATA, read_word(ES, BX));
        BX += 2;
        outw(VBE_DISPI_IOPORT_INDEX, VBE_DISPI_INDEX_YRES);
        outw(VBE_DISPI_IOPORT_DATA, read_word(ES, BX));
        BX += 2;
        outw(VBE_DISPI_IOPORT_INDEX, VBE_DISPI_INDEX_BPP);
        outw(VBE_DISPI_IOPORT_DATA, read_word(ES, BX));
        BX += 2;
        outw(VBE_DISPI_IOPORT_INDEX,VBE_DISPI_INDEX_ENABLE);
        outw(VBE_DISPI_IOPORT_DATA, enable);

        for(i = VBE_DISPI_INDEX_BANK; i <= VBE_DISPI_INDEX_Y_OFFSET; i++) {
            outw(VBE_DISPI_IOPORT_INDEX, i);
            outw(VBE_DISPI_IOPORT_DATA, read_word(ES, BX));
            BX += 2;
        }
    }
}

void read_fat_bs(uint8_t* buf, struct fat_BS* bs) {
  memcpy(bs->bootjmp,buf,3);
  memcpy(bs->oem_name,buf+3,8);
  
  bs->bytes_per_sector      = read_halfword(buf, 11);
  bs->sectors_per_cluster   = read_byte(buf, 13);
  bs->reserved_sector_count = read_halfword(buf, 14);
  bs->table_count           = read_byte(buf, 16);
  bs->root_entry_count      = read_halfword(buf, 17);
  bs->total_sectors_16      = read_halfword(buf, 19);
  bs->media_type            = read_byte(buf, 21);
  bs->table_size_16         = read_halfword(buf, 22);
  bs->sectors_per_track     = read_halfword(buf, 24);
  bs->head_side_count       = read_halfword(buf, 26);
  bs->hidden_sector_count   = read_word(buf, 28);
  bs->total_sectors_32      = read_word(buf, 32);

  if (bs->table_size_16==0) {
    memcpy(&bs->ext,buf+36,sizeof(struct fat_extBS_32));
  } else {
    bs->ext.fat16.bios_drive_num = read_byte(buf,36);
    bs->ext.fat16.reserved1 = read_byte(buf,37);
    bs->ext.fat16.boot_signature = read_byte(buf,38);
    bs->ext.fat16.volume_id = read_word(buf,39);
    memcpy(&bs->ext.fat16.volume_label,buf+43,11);
    memcpy(&bs->ext.fat16.fat_type_label,buf+54,8);
  }
}

static void reset_registers(void) {
	uint32_t vectortable = read_word(VECTOR_TABLE_OFFSET);

	// R[0..12] = bits(32) UNKNOWN {nop}

	SW(&sp_main,read_word(vectortable) & 0xfffffffc);

	// sp_process = ((bits(30) UNKNOWN):'00')
	SW(&sp_process, SR(&sp_process) & ~0x3);

	CORE_reg_write(LR_REG, 0xFFFFFFFF);

	uint32_t tmp = read_word(vectortable+4);
	bool tbit = tmp & 0x1;
	CORE_reg_write(PC_REG, tmp & 0xfffffffe);
	if (! (tmp & 0x1) ) {
		WARN("Reset vector %08x at %08x invalid\n", tmp, vectortable+4);
		CORE_ERR_unpredictable("Thumb bit must be set for M-series\n");
	}

	// ASPR = bits(32) UNKNOWN {nop}

	union ipsr_t ipsr = CORE_ipsr_read();
	ipsr.bits.exception = 0;
	CORE_ipsr_write(ipsr);

	union epsr_t epsr = CORE_epsr_read();
	epsr.bits.T = tbit;
	epsr.bits.ICI_IT_top = 0;
	epsr.bits.ICI_IT_bot = 0;
	CORE_epsr_write(epsr);
}

Elf32_Shdr *
elf_find_next_higher_section(Elf32_Word offset)
{
  Elf32_Shdr *section;
  Elf32_Shdr *higher;
  Elf32_Word sectionsize;
  int numsections;
  int i = 0;

  section = (Elf32_Shdr *)FILE_OFFSET(read_word(elf_header->e_shoff));
  sectionsize = read_half(elf_header->e_shentsize);
  numsections = read_half(elf_header->e_shnum);

  higher = NULL;

  for (i=0;i<numsections;i++) {
    if (read_word(section->sh_offset) >= offset) {
      if (higher == NULL) {
	higher = section;
      } else if (read_word(section->sh_offset) < read_word(higher->sh_offset)) {
	higher = section;
      }
    }
    
    section = (Elf32_Shdr *)((char *)section + sectionsize);
  }
  
  return higher;
}

unsigned int enqueue_key(uint8_t scan_code, uint8_t ascii_code)
{
    uint16_t    buffer_start, buffer_end, buffer_head, buffer_tail, temp_tail;

#if BX_CPU < 2
    buffer_start = 0x001E;
    buffer_end   = 0x003E;
#else
    buffer_start = read_word(0x0040, 0x0080);
    buffer_end   = read_word(0x0040, 0x0082);
#endif

    buffer_head = read_word(0x0040, 0x001A);
    buffer_tail = read_word(0x0040, 0x001C);

    temp_tail = buffer_tail;
    buffer_tail += 2;
    if (buffer_tail >= buffer_end)
        buffer_tail = buffer_start;

    if (buffer_tail == buffer_head)
        return(0);

    write_byte(0x0040, temp_tail, ascii_code);
    write_byte(0x0040, temp_tail+1, scan_code);
    write_word(0x0040, 0x001C, buffer_tail);
    return(1);
}

/* emu8k_detect:
 *  Locate the EMU8000. This tries to extract the base port from the E section
 *  of the BLASTER environment variable, and then does some test reads to check
 *  that there is an EMU8000 there.
 */
int emu8k_detect() {
 char *envvar;
 if (!(envvar=getenv("BLASTER"))) {
  sprintf(allegro_error,"BLASTER environment variable not set");
  return 0;
 }

 _emu8k_baseport=0;
 while (*envvar) {
  if (*envvar=='E') _emu8k_baseport=strtol(envvar+1,NULL,16);
  while ((*envvar!=' ')&&(*envvar!=0)) envvar++;
  if (*envvar) envvar++;
 }
 if (!_emu8k_baseport) {
  sprintf(allegro_error,"BLASTER environment variable has no E section");
  return 0;
 }

 sprintf(allegro_error,"AWE32 detection failed on port 0x%04x",_emu8k_baseport);

 if ((read_word(7, 0,3)&0x000f)!=0x000c) return 0;
 if ((read_word(1,29,1)&0x007e)!=0x0058) return 0;
 if ((read_word(1,30,1)&0x0003)!=0x0003) return 0;

 *allegro_error=0;
 return 1;
}

static zip_error get_compressed_data_offset(zip_file *zip, UINT64 *offset)
{
	file_error error;
	UINT32 read_length;

	/* make sure the file handle is open */
	if (zip->file == nullptr)
	{
		int filerr = osd_open(zip->filename, OPEN_FLAG_READ, &zip->file, &zip->length);
		if (filerr != FILERR_NONE)
			return ZIPERR_FILE_ERROR;
	}

	/* now go read the fixed-sized part of the local file header */
	error = osd_read(zip->file, zip->buffer, zip->header.local_header_offset, ZIPNAME, &read_length);
	if (error != FILERR_NONE || read_length != ZIPNAME)
		return (error == FILERR_NONE) ? ZIPERR_FILE_TRUNCATED : ZIPERR_FILE_ERROR;

	/* compute the final offset */
	*offset = zip->header.local_header_offset + ZIPNAME;
	*offset += read_word(zip->buffer + ZIPFNLN);
	*offset += read_word(zip->buffer + ZIPXTRALN);

	return ZIPERR_NONE;
}

void opcode_dict_unserialize(opcode_dict_t od, reader_t r, void* dl_handle) {
	long i,j,tot,typtot;
	const char* name;

	/* read dict header and check it against "DIC" */
	name = read_string(r);
	assert(!strcmp(name,"DIC"));
	
	/* read number of arrays, check it against OpcodeTypeMax */
	typtot = read_word(r);
	assert(typtot==OpcodeTypeMax);

	/* now for each array */
	for(i=0;i<OpcodeTypeMax;i+=1) {
		/* read number of records in array */
		tot = read_word(r);
		/* now for each record */
		for(j=0;j<tot;j+=1) {
			/* retrieve name */
			typtot = read_word(r);
			name = read_string(r);
			assert(typtot == 1+strlen(name));
			opcode_dict_add(od, i, name, opcode_stub_resolve(i,name,dl_handle));
		}
		/* read END OF RECORD */
		typtot = read_word(r);
		assert(typtot==0xFFFFFFFF);
	}
}

RegExp::RegExp(char* expression) {
	this->operations.reserve(64);
	this->transducers.reserve(64);
	this->expression = expression;
	
	for (ui i = 0; i < strlen(expression); i++) {
		switch(expression[i]) {
			case '<': {
					char* input = read_word(i);
					char* output = read_word(++i);
					i+=2;
					ui weight = read_number(i);
					Monoid monoid(input, output, weight);
					this->transducers.push_back(new Transducer(monoid));
				}
				break;
			case '|':
				this->operations.push_back(UNION);
				break;
			case '*':
				this->operations.push_back(STAR);
				break;
			case '.':
				this->operations.push_back(CONCAT);
				break;
		}
	}
}

void show_heap(void) {
  // TODO: change the code, since i change the heap_tail to one byte after
  void* p = heap_head;
  DebugStr("-----------------\n");
  DebugStr("heap_head = %x, heap size = %u\n",
           p, (char*)heap_tail  - (char*)heap_head);
  DebugStr("-----------------\n");
  DebugStr("%x\n", (char*)p + WSIZE);
  DebugStr("%x\n", (char*)p + 2 * WSIZE);
  DebugStr("-----------------\n");
  p = (char*)p + 3 * WSIZE;
  assert(p < heap_tail);
  while (get_size(p) > 0) {
    assert(p < heap_tail);
    DebugStr("hdrp:%x val = ", p);
    to_hex_str(*(size_t*)p, 1);
    DebugStr("size = %u, ALLOC = %d, PREV_ALLOC = %d\n",
             get_size(p), !!get_alloc(p), !!get_prev_alloc(p));
    void *ftrp = (char*)p + get_size(p) - WSIZE;
    DebugStr("ftrp:%x val = ", ftrp);
    to_hex_str(*(size_t*)ftrp, 1);
    if (!get_alloc(p)) { // if current block is not allocated, header = footer
      assert(read_word(p) == read_word(ftrp));
    }
    DebugStr("-----------------\n");
    p += get_size(p);
  }
  DebugStr("heap_tail = %x\n", p);
  DebugStr("-----------------\n");
}

void EEPROM::loadCalibration(int16_t * xMin, int16_t * xMax, int16_t * yMin, int16_t * yMax)
{
  *xMin = read_word(EEPROM_CAL_XMIN);
  *xMax = read_word(EEPROM_CAL_XMAX);
  *yMin = read_word(EEPROM_CAL_YMIN);
  *yMax = read_word(EEPROM_CAL_YMAX);
}

Elf32_Shdr *
elf_find_section_named(char *name)
{
  Elf32_Shdr *section;
  Elf32_Shdr *strtab_section;
  Elf32_Word sectionsize;
  int numsections;
  char *strtab;
  int i = 0;

  section = (Elf32_Shdr *)FILE_OFFSET(read_word(elf_header->e_shoff));

  strtab_section = elf_find_section_num(read_half(elf_header->e_shstrndx));
  
  strtab = (char *)FILE_OFFSET(read_word(strtab_section->sh_offset));
  
  sectionsize = read_half(elf_header->e_shentsize);
  numsections = read_half(elf_header->e_shnum);

  for (i=0;i<numsections;i++) {
    if (strcmp(&strtab[read_word(section->sh_name)], name) == 0) {
      return section;
    }
    section = (Elf32_Shdr *)((char *)section + sectionsize);
  }
  return NULL;
}

/*
 * read_images: Reads the images from and mnist image db file and puts the
 *              images into and array of vectors.
 *
 * Parameters:
 *  - train: boolean value, read from training db if 0, test db if 1
 *
 * Return value:
 *  - array of vectors containing mnist images
 */ 
mnist_images_t read_images(uint32_t train)
{
    // Set the filename based the mode (train or test)
    char *full_path;
    if (train) {
        full_path = concat_fname(mnist_path, train_image_fname);
    } else {
        full_path = concat_fname(mnist_path, test_image_fname);
    }

    // Open the file for reading
    char *mode = FILE_MODE;
    FILE *fp = Fopen(full_path, mode); 

    // Read the header of the file
    uint8_t header[IMAGE_HEADER_SIZE];
    Fread(header, sizeof(uint8_t), IMAGE_HEADER_SIZE, fp);

    // Extract size info from mnist db header
    uint32_t num_images = read_word(header, NUM_ITEMS_OFFSET);
    uint32_t rows = read_word(header, ROW_OFFSET);
    uint32_t cols = read_word(header, COL_OFFSET);
    uint32_t img_size = rows * cols;

    // Create array of mnist image vectors
    vector_t *mnist_data = (vector_t*) Calloc(num_images, sizeof(vector_t));
    
    // Populate vectors with one image each
    for (uint32_t i = 0; i < num_images; i++) {
        mnist_data[i] = Vector((size_t) img_size);

        uint8_t *image_bytes = (uint8_t*) Calloc(img_size, sizeof(uint8_t));
        uint32_t actual_size;
        // Read img_size bytes from the db file into the byte array
        if ((actual_size = fread(image_bytes, sizeof(uint8_t), img_size, fp)) < img_size) {
            Free(image_bytes);
            for (uint32_t i = 0; i < num_images; i++) vector_destroy(mnist_data[i]);
            return NULL;
        }

        // Move 8 bit data to 32 bit integer for more precision
        uint32_t *vector_data = (uint32_t*) Calloc(img_size, sizeof(uint32_t));
        for (uint32_t j = 0; j < img_size; j++) {
            vector_data[j] = (uint32_t) image_bytes[j];
        }
        mnist_data[i]->data = vector_data;
        Free(image_bytes);
    }

    // Create the mnist_images_t pointer and populate the struct it points to
    mnist_images_t mnist_imgs = Mnist_images((size_t) num_images); 
    mnist_imgs->imgs = mnist_data;

    Free(full_path);
    Fclose(fp);
    return mnist_imgs;
}

print_bin(){
	if(dbg.flag != 0)puts("");
	return;
	printf(" |%04X %04X %04X %04X\n", 
			read_word(PC-2),
			read_word(PC),
			read_word(PC+2),
			read_word(PC+4));
}