@c
@c COPYRIGHT (c) 1988-2008.
@c On-Line Applications Research Corporation (OAR).
@c All rights reserved.
@c
@c $Id$
@c
@chapter Memory Commands
@section Introduction
The RTEMS shell has the following memory commands:
@itemize @bullet
@item @code{mdump} - Display contents of memory
@item @code{wdump} - Display contents of memory (word)
@item @code{medit} - Modify contents of memory
@item @code{mfill} - File memory with pattern
@item @code{mmove} - Move contents of memory
@item @code{malloc} - Obtain information on C Program Heap
@end itemize
@section Commands
This section details the Memory Commands available. A
subsection is dedicated to each of the commands and
describes the behavior and configuration of that
command as well as providing an example usage.
@c
@c
@c
@page
@subsection mdump - display contents of memory
@pgindex mdump
@subheading SYNOPSYS:
@example
mdump [address [length]]
@end example
@subheading DESCRIPTION:
This command displays the contents of memory at the @code{address}
and @code{length} in bytes specified on the command line.
When @code{length} is not provided, it defaults to @code{320} which
is twenty lines of output with sixteen bytes of output per line.
When @code{address} is not provided, it defaults to @code{0x00000000}.
@subheading EXIT STATUS:
This command always returns 0 to indicate success.
@subheading NOTES:
Dumping memory from a non-existent address may result in an unrecoverable
program fault.
@subheading EXAMPLES:
The following is an example of how to use @code{mdump}:
@smallexample
SHLL [/] $ mdump 0x10000 32
0x0001000000 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00 ................
0x0001001000 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00 ................
SHLL [/] $ mdump 0x02000000 32
0x02000000A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 00 .H..)..3.."...!.
0x02000010A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 01 .H..)..3.."...!.
SHLL [/] $ mdump 0x02001000 32
0x0200100003 00 80 00 82 10 60 00-81 98 40 00 83 48 00 00 ......`...@..H..
0x0200101084 00 60 01 84 08 A0 07-86 10 20 01 87 28 C0 02 ..`....... ..(..
@end smallexample
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_MDUMP
@findex CONFIGURE_SHELL_COMMAND_MDUMP
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_MDUMP} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_MDUMP} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_mdump
The @code{mdump} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_mdump(
int argc,
char **argv
);
@end example
The configuration structure for the @code{mdump} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_MDUMP_Command;
@end example
@c
@c
@c
@page
@subsection wdump - display contents of memory (word)
@pgindex wdump
@subheading SYNOPSYS:
@example
wdump [address [length]]
@end example
@subheading DESCRIPTION:
This command displays the contents of memory at the @code{address}
and @code{length} in bytes specified on the command line.
When @code{length} is not provided, it defaults to @code{320} which
is twenty lines of output with sixteen bytes of output per line.
When @code{address} is not provided, it defaults to @code{0x00000000}.
@subheading EXIT STATUS:
This command always returns 0 to indicate success.
@subheading NOTES:
Dumping memory from a non-existent address may result in an unrecoverable
program fault.
@subheading EXAMPLES:
The following is an example of how to use @code{wdump}:
@smallexample
SHLL [/] $ wdump 0x02010000 32
0x02010000 0201 08D8 0201 08C0-0201 08AC 0201 0874 ...............t
0x02010010 0201 0894 0201 0718-0201 0640 0201 0798 ...........@....
@end smallexample
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_WDUMP
@findex CONFIGURE_SHELL_COMMAND_WDUMP
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_WDUMP} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_WDUMP} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_wdump
The @code{wdump} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_wdump(
int argc,
char **argv
);
@end example
The configuration structure for the @code{wdump} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_WDUMP_Command;
@end example
@c
@c
@c
@page
@subsection medit - modify contents of memory
@pgindex medit
@subheading SYNOPSYS:
@example
medit address value1 [value2 ... valueN]
@end example
@subheading DESCRIPTION:
This command is used to modify the contents of the memory starting
at @code{address} using the octets specified by the parameters
@code{value1} through @code{valueN}.
@subheading EXIT STATUS:
This command returns 0 on success and non-zero if an error is encountered.
@subheading NOTES:
Dumping memory from a non-existent address may result in an unrecoverable
program fault.
@subheading EXAMPLES:
The following is an example of how to use @code{medit}:
@smallexample
SHLL [/] $ mdump 0x02000000 32
0x02000000 A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 00 .H..)..3.."...!.
0x02000010 A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 01 .H..)..3.."...!.
SHLL [/] $ medit 0x02000000 0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08 0x09
SHLL [/] $ mdump 0x02000000 32
0x02000000 01 02 03 04 05 06 07 08-09 00 22 BC A6 10 21 00 .........."...!.
0x02000010 A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 01 .H..)..3.."...!.
@end smallexample
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_MEDIT
@findex CONFIGURE_SHELL_COMMAND_MEDIT
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_MEDIT} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_MEDIT} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_medit
The @code{medit} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_medit(
int argc,
char **argv
);
@end example
The configuration structure for the @code{medit} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_MEDIT_Command;
@end example
@c
@c
@c
@page
@subsection mfill - file memory with pattern
@pgindex mfill
@subheading SYNOPSYS:
@example
mfill address length value
@end example
@subheading DESCRIPTION:
This command is used to fill the memory starting at @code{address}
for the specified @code{length} in octets when the specified at
@code{value}.
@subheading EXIT STATUS:
This command returns 0 on success and non-zero if an error is encountered.
@subheading NOTES:
Filling a non-existent address range may result in an unrecoverable
program fault. Similarly overwriting interrupt vector tables, code
space or critical data areas can be fatal as shown in the example.
@subheading EXAMPLES:
In this example, the address used (@code{0x23d89a0}) as the base
address of the filled area is the end of the stack for the
Idle thread. This address was determined manually using gdb and
is very specific to this application and BSP. The first command
in this example is an @code{mdump} to display the initial contents
of this memory. We see that the first 8 bytes are 0xA5 which is
the pattern used as a guard by the Stack Checker. On
the first context switch after the pattern is overwritten
by the @code{mfill} command, the Stack Checker detect the pattern
has been corrupted and generates a fatal error.
@smallexample
SHLL [/] $ mdump 0x23d89a0 16
0x023D89A0 A5 A5 A5 A5 A5 A5 A5 A5-FE ED F0 0D 0B AD 0D 06 ................
SHLL [/] $ mfill 0x23d89a0 13 0x5a
SHLL [/] $ BLOWN STACK!!! Offending task(0x23D4418): id=0x09010001; name=0x0203D908
stack covers range 0x23D89A0 - 0x23D99AF (4112 bytes)
Damaged pattern begins at 0x023D89A8 and is 16 bytes long
@end smallexample
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_MFILL
@findex CONFIGURE_SHELL_COMMAND_MFILL
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_MFILL} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_MFILL} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_mfill
The @code{mfill} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_mfill(
int argc,
char **argv
);
@end example
The configuration structure for the @code{mfill} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_MFILL_Command;
@end example
@c
@c
@c
@page
@subsection mmove - move contents of memory
@pgindex mmove
@subheading SYNOPSYS:
@example
mmove dst src length
@end example
@subheading DESCRIPTION:
This command is used to copy the contents of the memory
starting at @code{src} to the memory located at @code{dst}
for the specified @code{length} in octets.
@subheading EXIT STATUS:
This command returns 0 on success and non-zero if an error is encountered.
@subheading NOTES:
NONE
@subheading EXAMPLES:
The following is an example of how to use @code{mmove}:
@smallexample
SHLL [/] $ mdump 0x023d99a0 16
0x023D99A0 A5 A5 A5 A5 A5 A5 A5 A5-A5 A5 A5 A5 A5 A5 A5 A5 ................
SHLL [/] $ mdump 0x02000000 16
0x02000000 A1 48 00 00 29 00 80 33-81 C5 22 BC A6 10 21 00 .H..)..3.."...!.
SHLL [/] $ mmove 0x023d99a0 0x02000000 13
SHLL [/] $ mdump 0x023d99a0 16
0x023D99A0 A1 48 00 00 29 00 80 33-81 C5 22 BC A6 A5 A5 A5 .H..)..3..".....
@end smallexample
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_MMOVE
@findex CONFIGURE_SHELL_COMMAND_MMOVE
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_MMOVE} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_MMOVE} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_mmove
The @code{mmove} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_mmove(
int argc,
char **argv
);
@end example
The configuration structure for the @code{mmove} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_MMOVE_Command;
@end example
@c
@c
@c
@page
@subsection malloc - obtain information on C program heap
@pgindex malloc
@subheading SYNOPSYS:
@example
malloc [info|stats]
@end example
@subheading DESCRIPTION:
This command prints either information or statistics about the
C Program Heap used by the @code{malloc} family of calls based upon
the value of the first argument passed to the command.
When the subcommand @code{info} is specified, information on the
current state of the C Program Heap is reported. This includes the following
information:
@itemize @bullet
@item Number of free blocks
@item Largest free block
@item Total bytes free
@item Number of used blocks
@item Largest used block
@item Total bytes used
@end itemize
When the subcommand @code{stats} is specified, statistics on the
the C Program Heap are reported. Malloc Family Statistics must
be enabled for all of the values to be updated. The statistics
available includes the following information:
@itemize @bullet
@item
@item Currently available memory (in kilobytes)
@item Currently allocated memory (in kilobytes)
@item Maximum amount of memory ever allocated (in kilobytes)
@item Lifetime tally of allocated memory (in kilobytes)
@item Lifetime tally of freed memory (in kilobytes)
@item Number of calls to @code{malloc}
@item Number of calls to @code{free}
@item Number of calls to @code{realloc}
@item Number of calls to @code{calloc}
@end itemize
@subheading EXIT STATUS:
This command returns 0 on success and non-zero if an error is encountered.
@subheading NOTES:
@findex CONFIGURE_MALLOC_STATISTICS
The @code{CONFIGURE_MALLOC_STATISTICS} @code{confdefs.h} constant
must be defined when the application is configured for the full
set of statistics information to be available.
@subheading EXAMPLES:
The following is an example of how to use the @code{malloc} command.
@example
SHLL [/] $ malloc info
Number of free blocks: 3
Largest free block: 3626672
Total bytes free: 3627768
Number of used blocks: 130
Largest used block: 1048
Total bytes used: 10136
SHLL [/] $ malloc stats
Malloc statistics
avail:3552k allocated:9k (0%) max:10k (0%) lifetime:21k freed:12k
Call counts: malloc:203 free:93 realloc:0 calloc:20
SHLL [/] $ malloc info
Number of free blocks: 3
Largest free block: 3626672
Total bytes free: 3627768
Number of used blocks: 130
Largest used block: 1048
Total bytes used: 10136
SHLL [/] $ malloc stats
Malloc statistics
avail:3552k allocated:9k (0%) max:10k (0%) lifetime:23k freed:14k
Call counts: malloc:205 free:95 realloc:0 calloc:20
@end example
Note that in the above example, the lifetime allocated and free
values have increased between the two calls to @code{malloc stats}
even though the amount of memory available in the C Program Heap
is the same in both the @code{malloc info} invocations. This indicates
that memory was allocated and freed as a side-effect of the commands.
@subheading CONFIGURATION:
@findex CONFIGURE_SHELL_NO_COMMAND_MALLOC
@findex CONFIGURE_SHELL_COMMAND_MALLOC
This command is included in the default shell command set.
When building a custom command set, define
@code{CONFIGURE_SHELL_COMMAND_MALLOC} to have this
command included.
This command can be excluded from the shell command set by
defining @code{CONFIGURE_SHELL_NO_COMMAND_MALLOC} when all
shell commands have been configured.
@subheading PROGRAMMING INFORMATION:
@findex rtems_shell_rtems_main_malloc
The @code{malloc} is implemented by a C language function
which has the following prototype:
@example
int rtems_shell_rtems_main_malloc(
int argc,
char **argv
);
@end example
The configuration structure for the @code{malloc} has the
following prototype:
@example
extern rtems_shell_cmd_t rtems_shell_MALLOC_Command;
@end example
