blob: 7ab2e28c8fe8c7a30fc5cfeb231b27b416e967d2 [file] [log] [blame]
/*
/usr/src/ext2ed/init.c
A part of the extended file system 2 disk editor.
--------------------------------
Various initialization routines.
--------------------------------
First written on: April 9 1995
Copyright (C) 1995 Gadi Oxman
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_READLINE
#include <readline.h>
#endif
#include <signal.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include "ext2ed.h"
char lines_s [80],cols_s [80];
void signal_handler (void);
void prepare_to_close (void)
{
close_windows ();
if (device_handle!=NULL)
fclose (device_handle);
free_user_commands (&general_commands);
free_user_commands (&ext2_commands);
free_struct_descriptors ();
}
int init (void)
{
printf ("Initializing ...\n");
if (!process_configuration_file ()) {
fprintf (stderr,"Error - Unable to complete configuration. Quitting.\n");
return (0);
};
general_commands.last_command=-1; /* No commands whatsoever meanwhile */
ext2_commands.last_command=-1;
add_general_commands (); /* Add the general commands, aviable always */
device_handle=NULL; /* Notice that our device is still not set up */
device_offset=-1;
current_type=NULL; /* No filesystem specific types yet */
remember_lifo.entries_count=0; /* Object memory is empty */
init_windows (); /* Initialize the NCURSES interface */
init_readline (); /* Initialize the READLINE interface */
init_signals (); /* Initialize the signal handlers */
write_access=0; /* Write access disabled */
strcpy (last_command_line,"help"); /* Show the help screen to the user */
dispatch ("help");
return (1); /* Success */
}
void add_general_commands (void)
{
add_user_command (&general_commands,"help","EXT2ED help system",help);
add_user_command (&general_commands,"set","Changes a variable in the current object",set);
add_user_command (&general_commands,"setdevice","Selects the filesystem block device (e.g. /dev/hda1)",set_device);
add_user_command (&general_commands,"setoffset","Moves asynchronicly in the filesystem",set_offset);
add_user_command (&general_commands,"settype","Tells EXT2ED how to interpert the current object",set_type);
add_user_command (&general_commands,"show","Displays the current object",show);
add_user_command (&general_commands,"pgup","Scrolls data one page up",pgup);
add_user_command (&general_commands,"pgdn","Scrolls data one page down",pgdn);
add_user_command (&general_commands,"redraw","Redisplay the screen",redraw);
add_user_command (&general_commands,"remember","Saves the current position and data information",remember);
add_user_command (&general_commands,"recall","Gets back to the saved object position",recall);
add_user_command (&general_commands,"enablewrite","Enters Read/Write mode - Allows changing the filesystem",enable_write);
add_user_command (&general_commands,"disablewrite","Enters read only mode",disable_write);
add_user_command (&general_commands,"writedata","Write data back to disk",write_data);
add_user_command (&general_commands,"next","Moves to the next byte in hex mode",next);
add_user_command (&general_commands,"prev","Moves to the previous byte in hex mode",prev);
}
void add_ext2_general_commands (void)
{
add_user_command (&ext2_commands,"super","Moves to the superblock of the filesystem",type_ext2___super);
add_user_command (&ext2_commands,"group","Moves to the first group descriptor",type_ext2___group);
add_user_command (&ext2_commands,"cd","Moves to the directory specified",type_ext2___cd);
}
int set_struct_descriptors (char *file_name)
{
FILE *fp;
char current_line [500],current_word [50],*ch;
char variable_name [50],variable_type [20];
struct struct_descriptor *current_descriptor;
if ( (fp=fopen (file_name,"rt"))==NULL) {
wprintw (command_win,"Error - Failed to open descriptors file %s\n",file_name);
refresh_command_win (); return (0);
};
while (!feof (fp)) {
fgets (current_line,500,fp);
if (feof (fp)) break;
ch=parse_word (current_line,current_word);
if (strcmp (current_word,"struct")==0) {
ch=parse_word (ch,current_word);
current_descriptor=add_new_descriptor (current_word);
while (strchr (current_line,'{')==NULL) {
fgets (current_line,500,fp);
if (feof (fp)) break;
};
if (feof (fp)) break;
fgets (current_line,500,fp);
while (strchr (current_line,'}')==NULL) {
while (strchr (current_line,';')==NULL) {
fgets (current_line,500,fp);
if (strchr (current_line,'}')!=NULL) break;
};
if (strchr (current_line,'}') !=NULL) break;
ch=parse_word (current_line,variable_type);
ch=parse_word (ch,variable_name);
while (variable_name [strlen (variable_name)-1]!=';') {
strcpy (variable_type,variable_name);
ch=parse_word (ch,variable_name);
};
variable_name [strlen (variable_name)-1]=0;
add_new_variable (current_descriptor,variable_type,variable_name);
fgets (current_line,500,fp);
};
};
};
fclose (fp);
return (1);
}
void free_struct_descriptors (void)
{
struct struct_descriptor *ptr,*next;
ptr=first_type;
while (ptr!=NULL) {
next=ptr->next;
free_user_commands (&ptr->type_commands);
free (ptr);
ptr=next;
}
first_type=last_type=current_type=NULL;
}
void free_user_commands (struct struct_commands *ptr)
{
int i;
for (i=0;i<=ptr->last_command;i++) {
free (ptr->names [i]);
free (ptr->descriptions [i]);
}
ptr->last_command=-1;
}
struct struct_descriptor *add_new_descriptor (char *name)
{
struct struct_descriptor *ptr;
ptr = malloc (sizeof (struct struct_descriptor));
if (ptr == NULL) {
printf ("Error - Can not allocate memory - Quitting\n");
exit (1);
}
memset(ptr, 0, sizeof(struct struct_descriptor));
ptr->prev = ptr->next = NULL;
strcpy (ptr->name,name);
ptr->length=0;
ptr->fields_num=0;
if (first_type==NULL) {
first_type = last_type = ptr;
} else {
ptr->prev = last_type; last_type->next = ptr; last_type=ptr;
}
ptr->type_commands.last_command=-1;
fill_type_commands (ptr);
return (ptr);
}
struct type_table {
char *name;
int field_type;
int len;
};
struct type_table type_table[] = {
{ "long", FIELD_TYPE_INT, 4 },
{ "short", FIELD_TYPE_INT, 2 },
{ "char", FIELD_TYPE_CHAR, 1 },
{ "__u32", FIELD_TYPE_UINT, 4 },
{ "__s32", FIELD_TYPE_INT, 4 },
{ "__u16", FIELD_TYPE_UINT, 2 },
{ "__s16", FIELD_TYPE_INT, 2 },
{ "__u8", FIELD_TYPE_UINT, 1 },
{ "__s8", FIELD_TYPE_INT, 1 },
{ 0, 0, 0 }
};
void add_new_variable (struct struct_descriptor *ptr,char *v_type,char *v_name)
{
short len=1;
char field_type=FIELD_TYPE_INT;
struct type_table *p;
strcpy (ptr->field_names [ptr->fields_num],v_name);
ptr->field_positions [ptr->fields_num]=ptr->length;
for (p = type_table; p->name; p++) {
if (strcmp(v_type, p->name) == 0) {
len = p->len;
field_type = p->field_type;
break;
}
}
if (p->name == 0) {
if (strncmp(v_type, "char[", 5) == 0) {
len = atoi(v_type+5);
field_type = FIELD_TYPE_CHAR;
} else {
printf("Unknown type %s for field %s\n", v_type, v_name);
exit(1);
}
}
ptr->field_lengths [ptr->fields_num] = len;
ptr->field_types [ptr->fields_num] = field_type;
ptr->length+=len;
ptr->fields_num++;
}
void fill_type_commands (struct struct_descriptor *ptr)
/*
Set specific type user commands.
*/
{
if (strcmp ((ptr->name),"file")==0) {
add_user_command (&ptr->type_commands,"show","Shows file data",type_file___show);
add_user_command (&ptr->type_commands,"inode","Returns to the inode of the current file",type_file___inode);
add_user_command (&ptr->type_commands,"display","Specifies data format - text or hex",type_file___display);
add_user_command (&ptr->type_commands,"next","Pass to next byte",type_file___next);
add_user_command (&ptr->type_commands,"prev","Pass to the previous byte",type_file___prev);
add_user_command (&ptr->type_commands,"offset","Pass to a specified byte in the current block",type_file___offset);
add_user_command (&ptr->type_commands,"nextblock","Pass to next file block",type_file___nextblock);
add_user_command (&ptr->type_commands,"prevblock","Pass to the previous file block",type_file___prevblock);
add_user_command (&ptr->type_commands,"block","Specify which file block to edit",type_file___block);
add_user_command (&ptr->type_commands,"remember","Saves the file\'s inode position for later reference",type_file___remember);
add_user_command (&ptr->type_commands,"set","Sets the current byte",type_file___set);
add_user_command (&ptr->type_commands,"writedata","Writes the current block to the disk",type_file___writedata);
}
if (strcmp ((ptr->name),"ext2_inode")==0) {
add_user_command (&ptr->type_commands,"show","Shows inode data",type_ext2_inode___show);
add_user_command (&ptr->type_commands,"next","Move to next inode in current block group",type_ext2_inode___next);
add_user_command (&ptr->type_commands,"prev","Move to next inode in current block group",type_ext2_inode___prev);
add_user_command (&ptr->type_commands,"group","Move to the group descriptors of the current inode table",type_ext2_inode___group);
add_user_command (&ptr->type_commands,"entry","Move to a specified entry in the current inode table",type_ext2_inode___entry);
add_user_command (&ptr->type_commands,"file","Display file data of the current inode",type_ext2_inode___file);
add_user_command (&ptr->type_commands,"dir","Display directory data of the current inode",type_ext2_inode___dir);
}
if (strcmp ((ptr->name),"dir")==0) {
add_user_command (&ptr->type_commands,"show","Shows current directory data",type_dir___show);
add_user_command (&ptr->type_commands,"inode","Returns to the inode of the current directory",type_dir___inode);
add_user_command (&ptr->type_commands,"next","Pass to the next directory entry",type_dir___next);
add_user_command (&ptr->type_commands,"prev","Pass to the previous directory entry",type_dir___prev);
add_user_command (&ptr->type_commands,"followinode","Follows the inode specified in this directory entry",type_dir___followinode);
add_user_command (&ptr->type_commands,"remember","Remember the inode of the current directory entry",type_dir___remember);
add_user_command (&ptr->type_commands,"cd","Changes directory relative to the current directory",type_dir___cd);
add_user_command (&ptr->type_commands,"entry","Moves to a specified entry in the current directory",type_dir___entry);
add_user_command (&ptr->type_commands,"writedata","Writes the current entry to the disk",type_dir___writedata);
add_user_command (&ptr->type_commands,"set","Changes a variable in the current directory entry",type_dir___set);
}
if (strcmp ((ptr->name),"ext2_super_block")==0) {
add_user_command (&ptr->type_commands,"show","Displays the super block data",type_ext2_super_block___show);
add_user_command (&ptr->type_commands,"gocopy","Move to another backup copy of the superblock",type_ext2_super_block___gocopy);
add_user_command (&ptr->type_commands,"setactivecopy","Copies the current superblock to the main superblock",type_ext2_super_block___setactivecopy);
}
if (strcmp ((ptr->name),"ext2_group_desc")==0) {
add_user_command (&ptr->type_commands,"next","Pass to the next block group decriptor",type_ext2_group_desc___next);
add_user_command (&ptr->type_commands,"prev","Pass to the previous group descriptor",type_ext2_group_desc___prev);
add_user_command (&ptr->type_commands,"entry","Pass to a specific group descriptor",type_ext2_group_desc___entry);
add_user_command (&ptr->type_commands,"show","Shows the current group descriptor",type_ext2_group_desc___show);
add_user_command (&ptr->type_commands,"inode","Pass to the inode table of the current group block",type_ext2_group_desc___inode);
add_user_command (&ptr->type_commands,"gocopy","Move to another backup copy of the group descriptor",type_ext2_group_desc___gocopy);
add_user_command (&ptr->type_commands,"blockbitmap","Show the block allocation bitmap of the current group block",type_ext2_group_desc___blockbitmap);
add_user_command (&ptr->type_commands,"inodebitmap","Show the inode allocation bitmap of the current group block",type_ext2_group_desc___inodebitmap);
add_user_command (&ptr->type_commands,"setactivecopy","Copies the current group descriptor to the main table",type_ext2_super_block___setactivecopy);
}
if (strcmp ((ptr->name),"block_bitmap")==0) {
add_user_command (&ptr->type_commands,"show","Displays the block allocation bitmap",type_ext2_block_bitmap___show);
add_user_command (&ptr->type_commands,"entry","Moves to a specific bit",type_ext2_block_bitmap___entry);
add_user_command (&ptr->type_commands,"next","Moves to the next bit",type_ext2_block_bitmap___next);
add_user_command (&ptr->type_commands,"prev","Moves to the previous bit",type_ext2_block_bitmap___prev);
add_user_command (&ptr->type_commands,"allocate","Allocates the current block",type_ext2_block_bitmap___allocate);
add_user_command (&ptr->type_commands,"deallocate","Deallocates the current block",type_ext2_block_bitmap___deallocate);
}
if (strcmp ((ptr->name),"inode_bitmap")==0) {
add_user_command (&ptr->type_commands,"show","Displays the inode allocation bitmap",type_ext2_inode_bitmap___show);
add_user_command (&ptr->type_commands,"entry","Moves to a specific bit",type_ext2_inode_bitmap___entry);
add_user_command (&ptr->type_commands,"next","Moves to the next bit",type_ext2_inode_bitmap___next);
add_user_command (&ptr->type_commands,"prev","Moves to the previous bit",type_ext2_inode_bitmap___prev);
add_user_command (&ptr->type_commands,"allocate","Allocates the current inode",type_ext2_inode_bitmap___allocate);
add_user_command (&ptr->type_commands,"deallocate","Deallocates the current inode",type_ext2_inode_bitmap___deallocate);
}
}
void add_user_command (struct struct_commands *ptr,char *name,char *description,PF callback)
{
int num;
num=ptr->last_command;
if (num+1==MAX_COMMANDS_NUM) {
printf ("Internal Error - Can't add command %s\n",name);
return;
}
ptr->last_command=++num;
ptr->names [num]=(char *) malloc (strlen (name)+1);
strcpy (ptr->names [num],name);
if (*description!=0) {
ptr->descriptions [num]=(char *) malloc (strlen (description)+1);
strcpy (ptr->descriptions [num],description);
}
ptr->callback [num]=callback;
}
static unsigned int div_ceil(unsigned int a, unsigned int b)
{
if (!a)
return 0;
return ((a - 1) / b) + 1;
}
int set_file_system_info (void)
{
int ext2_detected=0;
struct ext2_super_block *sb;
file_system_info.super_block_offset=1024;
file_system_info.file_system_size=DefaultTotalBlocks*DefaultBlockSize;
low_read ((char *) &file_system_info.super_block,sizeof (struct ext2_super_block),file_system_info.super_block_offset);
sb=&file_system_info.super_block;
if (sb->s_magic == EXT2_SUPER_MAGIC)
ext2_detected=1;
if (ext2_detected)
wprintw (command_win,"Detected extended 2 file system on device %s\n",device_name);
else
wprintw (command_win,"Warning - Extended 2 filesystem not detected on device %s\n",device_name);
if (!ext2_detected && !ForceExt2)
wprintw (command_win,"You may wish to use the configuration option ForceExt2 on\n");
if (ForceExt2 && !ext2_detected)
wprintw (command_win,"Forcing extended 2 filesystem\n");
if (ForceDefault || !ext2_detected)
wprintw (command_win,"Forcing default parameters\n");
refresh_command_win ();
if (ext2_detected || ForceExt2) {
add_ext2_general_commands ();
if (!set_struct_descriptors (Ext2Descriptors))
return (0);
}
if (!ForceDefault && ext2_detected) {
file_system_info.block_size=EXT2_MIN_BLOCK_SIZE << sb->s_log_block_size;
if (file_system_info.block_size == EXT2_MIN_BLOCK_SIZE)
file_system_info.first_group_desc_offset=2*EXT2_MIN_BLOCK_SIZE;
else
file_system_info.first_group_desc_offset=file_system_info.block_size;
file_system_info.groups_count = div_ceil(sb->s_blocks_count,
sb->s_blocks_per_group);
file_system_info.inodes_per_block=file_system_info.block_size/sizeof (struct ext2_inode);
file_system_info.blocks_per_group=sb->s_inodes_per_group/file_system_info.inodes_per_block;
file_system_info.no_blocks_in_group=sb->s_blocks_per_group;
file_system_info.file_system_size=(sb->s_blocks_count-1)*file_system_info.block_size;
}
else {
file_system_info.file_system_size=DefaultTotalBlocks*DefaultBlockSize;
file_system_info.block_size=DefaultBlockSize;
file_system_info.no_blocks_in_group=DefaultBlocksInGroup;
}
if (file_system_info.file_system_size > 2147483647) {
wprintw (command_win,"Sorry, filesystems bigger than 2 GB are currently not supported\n");
return (0);
}
return (1);
}
void init_readline (void)
{
#ifdef HAVE_READLINE
rl_completion_entry_function=(Function *) complete_command;
#endif
}
void init_signals (void)
{
signal (SIGWINCH, signal_SIGWINCH_handler); /* Catch SIGWINCH */
signal (SIGTERM, signal_SIGTERM_handler);
signal (SIGSEGV, signal_SIGSEGV_handler);
}
void signal_SIGWINCH_handler (int sig_num)
{
redraw_request=1; /* We will handle it in main.c */
/* Reset signal handler */
signal (SIGWINCH, signal_SIGWINCH_handler);
}
void signal_SIGTERM_handler (int sig_num)
{
prepare_to_close ();
printf ("Terminated due to signal %d\n",sig_num);
exit (1);
}
void signal_SIGSEGV_handler (int sig_num)
{
prepare_to_close ();
printf ("Killed by signal %d!\n",sig_num);
exit (1);
}
int process_configuration_file (void)
{
char buffer [300];
char option [80],value [80];
FILE *fp;
strcpy (buffer, ETC_DIR);
strcat (buffer,"/ext2ed.conf");
if ((fp=fopen (buffer,"rt"))==NULL) {
fprintf (stderr,"Error - Unable to open configuration file %s\n",buffer);
return (0);
}
while (get_next_option (fp,option,value)) {
if (strcasecmp (option,"Ext2Descriptors")==0) {
strcpy (Ext2Descriptors,value);
}
else if (strcasecmp (option,"AlternateDescriptors")==0) {
strcpy (AlternateDescriptors,value);
}
else if (strcasecmp (option,"LogFile")==0) {
strcpy (LogFile,value);
}
else if (strcasecmp (option,"LogChanges")==0) {
if (strcasecmp (value,"on")==0)
LogChanges = 1;
else if (strcasecmp (value,"off")==0)
LogChanges = 0;
else {
fprintf (stderr,"Error - Illegal value: %s %s\n",option,value);
fclose (fp);return (0);
}
}
else if (strcasecmp (option,"AllowChanges")==0) {
if (strcasecmp (value,"on")==0)
AllowChanges = 1;
else if (strcasecmp (value,"off")==0)
AllowChanges = 0;
else {
fprintf (stderr,"Error - Illegal value: %s %s\n",option,value);
fclose (fp);return (0);
}
}
else if (strcasecmp (option,"AllowMountedRead")==0) {
if (strcasecmp (value,"on")==0)
AllowMountedRead = 1;
else if (strcasecmp (value,"off")==0)
AllowMountedRead = 0;
else {
fprintf (stderr,"Error - Illegal value: %s %s\n",option,value);
fclose (fp);return (0);
}
}
else if (strcasecmp (option,"ForceExt2")==0) {
if (strcasecmp (value,"on")==0)
ForceExt2 = 1;
else if (strcasecmp (value,"off")==0)
ForceExt2 = 0;
else {
fprintf (stderr,"Error - Illegal value: %s %s\n",option,value);
fclose (fp);return (0);
}
}
else if (strcasecmp (option,"DefaultBlockSize")==0) {
DefaultBlockSize = atoi (value);
}
else if (strcasecmp (option,"DefaultTotalBlocks")==0) {
DefaultTotalBlocks = strtoul (value,NULL,10);
}
else if (strcasecmp (option,"DefaultBlocksInGroup")==0) {
DefaultBlocksInGroup = strtoul (value,NULL,10);
}
else if (strcasecmp (option,"ForceDefault")==0) {
if (strcasecmp (value,"on")==0)
ForceDefault = 1;
else if (strcasecmp (value,"off")==0)
ForceDefault = 0;
else {
fprintf (stderr,"Error - Illegal value: %s %s\n",option,value);
fclose (fp);return (0);
}
}
else {
fprintf (stderr,"Error - Unknown option: %s\n",option);
fclose (fp);return (0);
}
}
printf ("Configuration completed\n");
fclose (fp);
return (1);
}
int get_next_option (FILE *fp,char *option,char *value)
{
char *ptr;
char buffer [600];
if (feof (fp)) return (0);
do{
if (feof (fp)) return (0);
fgets (buffer,500,fp);
} while (buffer [0]=='#' || buffer [0]=='\n');
ptr=parse_word (buffer,option);
ptr=parse_word (ptr,value);
return (1);
}
void check_mounted (char *name)
{
FILE *fp;
char *ptr;
char current_line [500],current_word [200];
mounted=0;
if ( (fp=fopen ("/etc/mtab","rt"))==NULL) {
wprintw (command_win,"Error - Failed to open /etc/mtab. Assuming filesystem is mounted.\n");
refresh_command_win ();mounted=1;return;
};
while (!feof (fp)) {
fgets (current_line,500,fp);
if (feof (fp)) break;
ptr=parse_word (current_line,current_word);
if (strcasecmp (current_word,name)==0) {
mounted=1;fclose (fp);return;
}
};
fclose (fp);
return;
}