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#include "monitor.h"
#include "minix.h"
/* #define DEBUG 1 /**/
#define SECTOR_SIZE 512
block_nr inode_tbl = 0; /* super.s_imap_blocks+super.s_zmap_blocks+2 */
static int fs_dir32 = 0; /* Using 30 char filenames ? */
struct file_pos {
inode_nr inode;
zone_nr seek_addr;
file_pos i_size; /* current file size in bytes */
mask_bits i_mode; /* File type */
zone_nr i_zone[NR_ZONE_NUMS]; /* block numbers from inode */
} current_file = { 0,0 };
static int first_time = 1;
static inode_nr current_dir = ROOT_INODE;
static block_nr fs_ind = 0;
static block_nr fs_block = 0;
static char fs_buf[BLOCK_SIZE]; /* For storing inodes and ind sectors */
static min_inode_open();
#define b_super(x) ((struct super_block *)(x))
#define b_dir(x) ((dir_struct*)(x))
min_open_file(fname)
char * fname;
{
char * sptr;
if( disk_heads == 0 ) return -1;
if( (sptr = read_sector(SUPER_BLOCK*BLOCK_SIZE/SECTOR_SIZE)) == 0 )
return -1;
/* Check super */
if(b_super(sptr)->s_magic == SUPER_MAGIC )
fs_dir32 = 0;
else if(b_super(sptr)->s_magic == SUPER_MAGIC2 )
fs_dir32 = 16;
else
return -1;
inode_tbl = b_super(sptr)->s_imap_blocks+b_super(sptr)->s_zmap_blocks+2;
/* Check for boot directory */
current_dir = ROOT_INODE;
if( min_name_open("boot") >= 0 && current_file.i_mode == I_DIRECTORY )
current_dir = current_file.inode;
#ifdef DEBUG
fprintf(stderr, "Opening minix file <%d>/%s[1,%d]\n",
current_dir,fname,fs_dir32+14);
#endif
return min_name_open(fname);
}
static
min_name_open(fname)
char * fname;
{
int do_dir = 0;
char dirbuf[1024];
long len;
int v;
inode_nr file_inode = 0;
if( strcmp(fname, ".") == 0 ) do_dir = 1;
/* open current_dir inode */
if( min_inode_open(current_dir) < 0 ) return -1;
/* scan for file */
for(len = min_file_length(); len>0; len-=1024)
{
if( min_read_block(dirbuf) < 0 ) break;
for(v=0; v<1024; v+= 16+fs_dir32)
{
if( b_dir(dirbuf+v)->d_inum == 0 )
continue;
#ifndef NOCOMMAND
if( do_dir )
{
if( b_dir(dirbuf+v)->d_name[0] == '.' )
continue;
if( fs_dir32 ) printf("%.30s\n", b_dir(dirbuf+v)->d_name);
else printf("%.14s\n", b_dir(dirbuf+v)->d_name);
}
else
#endif
if( strncmp(b_dir(dirbuf+v)->d_name, fname,14+fs_dir32) ==0)
{
file_inode = b_dir(dirbuf+v)->d_inum;
break;
}
}
}
/* open */
if( file_inode )
{
if( min_inode_open(file_inode) >= 0 ) return 0;
}
return -1;
}
static
min_inode_open(inode)
int inode;
{
int inode_sector = inode_tbl*BLOCK_SIZE/SECTOR_SIZE;
d_inode * sptr = 0;
int i;
min_close_file();
inode--;
inode_sector += inode/(SECTOR_SIZE/sizeof(d_inode));
if( (sptr = read_sector(inode_sector)) == 0 ) return -1;
sptr += inode%(SECTOR_SIZE/sizeof(d_inode));
current_file.i_mode = (sptr->i_mode & I_TYPE);
if( current_file.i_mode != I_REGULAR &&
current_file.i_mode != I_DIRECTORY )
return -1;
current_file.i_size = sptr->i_size;
for(i=0; i<NR_ZONE_NUMS; i++)
current_file.i_zone[i] = sptr->i_zone[i];
current_file.inode = inode+1;
return 0;
}
min_rewind_file()
{
current_file.seek_addr = 0;
return 0;
}
min_close_file()
{
if( current_file.inode == 0 ) return -1;
current_file.inode = 0;
current_file.seek_addr = 0;
fs_ind = 0;
return 0;
}
long
min_file_length()
{
if( current_file.inode == 0 ) return -1;
return current_file.i_size;
}
min_read_block(buffer)
char * buffer;
{
block_nr block_no;
if( current_file.seek_addr < NR_DZONE_NUM )
block_no = current_file.i_zone[current_file.seek_addr];
else if( current_file.seek_addr < NR_DZONE_NUM + NR_INDIRECTS )
{
if( fs_block != current_file.i_zone[NR_DZONE_NUM] )
{
block_no = current_file.i_zone[NR_DZONE_NUM];
read_fs_block(block_no, fs_buf);
fs_block = current_file.i_zone[NR_DZONE_NUM];
fs_ind = 0;
}
block_no = ((zone_nr*)fs_buf)[current_file.seek_addr-NR_DZONE_NUM];
}
else
{
int ind_block;
ind_block = current_file.seek_addr - NR_DZONE_NUM - NR_INDIRECTS;
if( fs_ind != ind_block/NR_INDIRECTS + 1 )
{
block_no = current_file.i_zone[NR_DZONE_NUM+1];
read_fs_block(block_no, fs_buf);
fs_block = current_file.i_zone[NR_DZONE_NUM+1];
block_no = ((zone_nr*)fs_buf)[ind_block/NR_INDIRECTS];
read_fs_block(block_no, fs_buf);
fs_block = current_file.i_zone[NR_DZONE_NUM];
fs_ind = ind_block/NR_INDIRECTS + 1;
}
block_no = ((zone_nr*)fs_buf)[ind_block%NR_INDIRECTS];
}
current_file.seek_addr++;
read_fs_block(block_no, buffer);
return 0;
}
read_fs_block(block_no, buffer)
block_nr block_no;
char * buffer;
{
long sector_no;
char * sptr;
if( block_no == 0 ) goto zappit;
sector_no = ((long)block_no) * BLOCK_SIZE/SECTOR_SIZE;
sptr = read_sector(sector_no);
if( sptr ) memcpy(buffer, sptr, SECTOR_SIZE);
else goto zappit;
sptr = read_sector(sector_no+1);
if( sptr ) memcpy(buffer+SECTOR_SIZE, sptr, SECTOR_SIZE);
else goto zappit;
return;
zappit:;
memset(buffer, '\0', 1024);
}
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