Commit graph

2764 commits

Author SHA1 Message Date
Andreas Bießmann
fc5fc76bda lib/hashtable.c: add CONFIG_ENV_MIN_ENTRIES
This patch adds a new config parameter for adjusting the calculation of
hash table size when importing a buffer.

When importing a extremely small buffer (e.g. the default_environment)
the old calculation generated a hash table which could hold at most the
buffer content but no more entires.

The new calculation add a fixed number of entries to the result to fit
better for small import buffers. This amount may be configured by the
user in board file to adjust the behaviour.

Signed-off-by: Andreas Biemann <andreas.devel@googlemail.com>
2010-10-06 22:46:35 +02:00
Wolfgang Denk
ea882baf9c New implementation for internal handling of environment variables.
Motivation:

* Old environment code used a pessimizing implementation:
  - variable lookup used linear search => slow
  - changed/added variables were added at the end, i. e. most
    frequently used variables had the slowest access times => slow
  - each setenv() would calculate the CRC32 checksum over the whole
    environment block => slow
* "redundant" envrionment was locked down to two copies
* No easy way to implement features like "reset to factory defaults",
  or to select one out of several pre-defined (previously saved) sets
  of environment settings ("profiles")
* No easy way to import or export environment settings

======================================================================

API Changes:

- Variable names starting with '#' are no longer allowed

  I didn't find any such variable names being used; it is highly
  recommended to follow standard conventions and start variable names
  with an alphanumeric character

- "printenv" will now print a backslash at the end of all but the last
  lines of a multi-line variable value.

  Multi-line variables have never been formally defined, allthough
  there is no reason not to use them. Now we define rules how to deal
  with them, allowing for import and export.

- Function forceenv() and the related code in saveenv() was removed.
  At the moment this is causing build problems for the only user of
  this code (schmoogie - which has no entry in MAINTAINERS); may be
  fixed later by implementing the "env set -f" feature.

Inconsistencies:

- "printenv" will '\\'-escape the '\n' in multi-line variables, while
  "printenv var" will not do that.

======================================================================

Advantages:

- "printenv" output much better readable (sorted)
- faster!
- extendable (additional variable properties can be added)
- new, powerful features like "factory reset" or easy switching
  between several different environment settings ("profiles")

Disadvantages:

- Image size grows by typically 5...7 KiB (might shrink a bit again on
  systems with redundant environment with a following patch series)

======================================================================

Implemented:

- env command with subcommands:

  - env print [arg ...]

    same as "printenv": print environment

  - env set [-f] name [arg ...]

    same as "setenv": set (and delete) environment variables

    ["-f" - force setting even for read-only variables - not
    implemented yet.]

  - end delete [-f] name

    not implemented yet

    ["-f" - force delete even for read-only variables]

  - env save

    same as "saveenv": save environment

  - env export [-t | -b | -c] addr [size]

    export internal representation (hash table) in formats usable for
    persistent storage or processing:

	-t:	export as text format; if size is given, data will be
		padded with '\0' bytes; if not, one terminating '\0'
		will be added (which is included in the "filesize"
		setting so you can for exmple copy this to flash and
		keep the termination).
	-b:	export as binary format (name=value pairs separated by
		'\0', list end marked by double "\0\0")
	-c:	export as checksum protected environment format as
		used for example by "saveenv" command
	addr:	memory address where environment gets stored
	size:	size of output buffer

	With "-c" and size is NOT given, then the export command will
	format the data as currently used for the persistent storage,
	i. e. it will use CONFIG_ENV_SECT_SIZE as output block size and
	prepend a valid CRC32 checksum and, in case of resundant
	environment, a "current" redundancy flag. If size is given, this
	value will be used instead of CONFIG_ENV_SECT_SIZE; again, CRC32
	checksum and redundancy flag will be inserted.

	With "-b" and "-t", always only the real data (including a
	terminating '\0' byte) will be written; here the optional size
	argument will be used to make sure not to overflow the user
	provided buffer; the command will abort if the size is not
	sufficient. Any remainign space will be '\0' padded.

        On successful return, the variable "filesize" will be set.
        Note that filesize includes the trailing/terminating '\0'
        byte(s).

        Usage szenario: create a text snapshot/backup of the current
	settings:

		=> env export -t 100000
		=> era ${backup_addr} +${filesize}
		=> cp.b 100000 ${backup_addr} ${filesize}

	Re-import this snapshot, deleting all other settings:

		=> env import -d -t ${backup_addr}

  - env import [-d] [-t | -b | -c] addr [size]

    import external format (text or binary) into hash table,
    optionally deleting existing values:

	-d:	delete existing environment before importing;
		otherwise overwrite / append to existion definitions
	-t:	assume text format; either "size" must be given or the
		text data must be '\0' terminated
	-b:	assume binary format ('\0' separated, "\0\0" terminated)
	-c:	assume checksum protected environment format
	addr:	memory address to read from
	size:	length of input data; if missing, proper '\0'
		termination is mandatory

  - env default -f

    reset default environment: drop all environment settings and load
    default environment

  - env ask name [message] [size]

    same as "askenv": ask for environment variable

  - env edit name

    same as "editenv": edit environment variable

  - env run

    same as "run": run commands in an environment variable

======================================================================

TODO:

- drop default env as implemented now; provide a text file based
  initialization instead (eventually using several text files to
  incrementally build it from common blocks) and a tool to convert it
  into a binary blob / object file.

- It would be nice if we could add wildcard support for environment
  variables; this is needed for variable name auto-completion,
  but it would also be nice to be able to say "printenv ip*" or
  "printenv *addr*"

- Some boards don't link any more due to the grown code size:
  DU405, canyonlands, sequoia, socrates.

	=> cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>,
	       Stefan Roese <sr@denx.de>,
	       Heiko Schocher <hs@denx.de>

- Dropping forceenv() causes build problems on schmoogie

	=> cc: Sergey Kubushyn <ksi@koi8.net>

- Build tested on PPC and ARM only; runtime tested with NOR and NAND
  flash only => needs testing!!

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Matthias Fuchs <matthias.fuchs@esd-electronics.com>,
Cc: Stefan Roese <sr@denx.de>,
Cc: Heiko Schocher <hs@denx.de>
Cc: Sergey Kubushyn <ksi@koi8.net>
2010-09-19 19:29:48 +02:00
Wolfgang Denk
a6826fbc5c Add hash table support as base for new environment code
This implementation is based on code from uClibc-0.9.30.3 but was
modified and extended for use within U-Boot.

Major modifications and extensions:

* hsearch() [modified / extended]:
  - While the standard version does not make any assumptions about
    the type of the stored data objects at all, this implementation
    works with NUL terminated strings only.
  - Instead of storing just pointers to the original objects, we
    create local copies so the caller does not need to care about the
    data any more.
  - The standard implementation does not provide a way to update an
    existing entry.  This version will create a new entry or update an
    existing one when both "action == ENTER" and "item.data != NULL".
  - hsearch_r(): Instead of returning 1 on success, we return the
    index into the internal hash table, which is also guaranteed to be
    positive.  This allows us direct access to the found hash table
    slot for example for functions like hdelete().
* hdelete() [added]:
  - The standard implementation of hsearch(3) does not provide any way
    to delete any entries from the hash table.  We extend the code to
    do that.
* hexport() [added]:
  - Export the data stored in the hash table in linearized form:
    Entries are exported as "name=value" strings, separated by an
    arbitrary (non-NUL, of course) separator character. This allows to
    use this function both when formatting the U-Boot environment for
    external storage (using '\0' as separator), but also when using it
    for the "printenv" command to print all variables, simply by using
    as '\n" as separator. This can also be used for new features like
    exporting the environment data as text file, including the option
    for later re-import.
  - The entries in the result list will be sorted by ascending key
    values.
* himport() [added]:
  - Import linearized data into hash table.  This is the inverse
    function to hexport(): it takes a linear list of "name=value"
    pairs and creates hash table entries from it.
  - Entries without "value", i. e. consisting of only "name" or
    "name=", will cause this entry to be deleted from the hash table.
  - The "flag" argument can be used to control the behaviour: when
    the H_NOCLEAR bit is set, then an existing hash table will kept,
    i. e. new data will be added to an existing hash table;
    otherwise, old data will be discarded and a new hash table will
    be created.
  - The separator character for the "name=value" pairs can be
    selected, so we both support importing from externally stored
    environment data (separated by NUL characters) and from plain text
    files (entries separated by newline characters).
  - To allow for nicely formatted text input, leading white space
    (sequences of SPACE and TAB chars) is ignored, and entries
    starting (after removal of any leading white space) with a '#'
    character are considered comments and ignored.
  - NOTE: this means that a variable name cannot start with a '#'
    character.
  - When using a non-NUL separator character, backslash is used as
    escape character in the value part, allowing for example fo
    multi-line values.
  - In theory, arbitrary separator characters can be used, but only
    '\0' and '\n' have really been tested.

Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-19 19:29:47 +02:00
Wolfgang Denk
54c6977e9c Add qsort - add support for sorting data arrays
Code adapted from uClibc-0.9.30.3

Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-19 19:29:47 +02:00
Wolfgang Denk
65cd3fa81f Add basic errno support.
Needed for hash table support; probably useful in a lot of other
places as well.

Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-19 19:29:47 +02:00
Reinhard Meyer
150f723665 display_buffer: fix misaligned buffer
use a union to cause necessary alignment per architecture

Signed-off-by: Reinhard Meyer <u-boot@emk-elektronik.de>
2010-09-13 13:15:07 +02:00
Mike Frysinger
64419e4751 print_buffer: optimize & shrink
Applying a little creative format string allows us to shrink the initial
data read & display loop by only calling printf once.  Re-using the local
data buffer to generate the string we want to display then allows us to
output everything with just one printf call instead of multiple calls to
the putc function.

The local stack buffer needs increasing by 1 byte, but the resulting code
shrink and speed up is worth it I think.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-08-09 00:28:38 +02:00
Wolfgang Denk
54841ab50c Make sure that argv[] argument pointers are not modified.
The hush shell dynamically allocates (and re-allocates) memory for the
argument strings in the "char *argv[]" argument vector passed to
commands.  Any code that modifies these pointers will cause serious
corruption of the malloc data structures and crash U-Boot, so make
sure the compiler can check that no such modifications are being done
by changing the code into "char * const argv[]".

This modification is the result of debugging a strange crash caused
after adding a new command, which used the following argument
processing code which has been working perfectly fine in all Unix
systems since version 6 - but not so in U-Boot:

int main (int argc, char **argv)
{
	while (--argc > 0 && **++argv == '-') {
/* ====> */	while (*++*argv) {
			switch (**argv) {
			case 'd':
				debug++;
				break;
			...
			default:
				usage ();
			}
		}
	}
	...
}

The line marked "====>" will corrupt the malloc data structures and
usually cause U-Boot to crash when the next command gets executed by
the shell.  With the modification, the compiler will prevent this with
an
	error: increment of read-only location '*argv'

N.B.: The code above can be trivially rewritten like this:

	while (--argc > 0 && **++argv == '-') {
		char *arg = *argv;
		while (*++arg) {
			switch (*arg) {
			...

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
2010-07-04 23:55:42 +02:00
Nick Thompson
f2d76ae4fd Avoid use of divides in print_size
Modification of print_size to avoid use of divides and especially
long long divides. Keep the binary scale factor in terms of bit
shifts instead. This should be faster, since the previous code
gave the compiler no clues that the divides where always powers
of two, preventing optimisation.

Signed-off-by: Nick Thompson <nick.thompson@ge.com>
Acked-by: Timur Tabi <timur@freescale.com>
2010-05-17 23:23:39 +02:00
Timur Tabi
4b42c9059e allow print_size to print large numbers on 32-bit systems
Modify print_size() so that it can accept numbers larger than 4GB on 32-bit
systems.

Add support for display terabyte, petabyte, and exabyte sizes.  Change the
output to use International Electrotechnical Commission binary prefix standard.

Signed-off-by: Timur Tabi <timur@freescale.com>
2010-05-05 22:17:34 +02:00
Timur Tabi
52dbac69c2 fix print_size printing fractional gigabyte numbers on 32-bit platforms
In print_size(), the math that calculates the fractional remainder of a number
used the same integer size as a physical address.  However, the "10 *" factor
of the algorithm means that a large number (e.g. 1.5GB) can overflow the
integer if we're running on a 32-bit system.  Therefore, we need to
disassociate this function from the size of a physical address.

Signed-off-by: Timur Tabi <timur@freescale.com>
2010-05-05 22:17:07 +02:00
Stefan Roese
a47a12becf Move arch/ppc to arch/powerpc
As discussed on the list, move "arch/ppc" to "arch/powerpc" to
better match the Linux directory structure.

Please note that this patch also changes the "ppc" target in
MAKEALL to "powerpc" to match this new infrastructure. But "ppc"
is kept as an alias for now, to not break compatibility with
scripts using this name.

Signed-off-by: Stefan Roese <sr@denx.de>
Acked-by: Wolfgang Denk <wd@denx.de>
Acked-by: Detlev Zundel <dzu@denx.de>
Acked-by: Kim Phillips <kim.phillips@freescale.com>
Cc: Peter Tyser <ptyser@xes-inc.com>
Cc: Anatolij Gustschin <agust@denx.de>
2010-04-21 23:42:38 +02:00
Peter Tyser
0de71d5071 Move libfdt/ into lib/
Move the libfdt directory into the common lib/ directory to clean up the
top-level directory.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2010-04-13 09:13:04 +02:00
Peter Tyser
78acc472d9 Rename lib_generic/ to lib/
Now that the other architecture-specific lib directories have been
moved out of the top-level directory there's not much reason to have the
'_generic' suffix on the common lib directory.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
2010-04-13 09:13:04 +02:00