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2010-09-19New implementation for internal handling of environment variables.Wolfgang Denk
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>
2010-09-19Add hash table support as base for new environment codeWolfgang Denk
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>
2010-09-19Add qsort - add support for sorting data arraysWolfgang Denk
Code adapted from uClibc-0.9.30.3 Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-19Add basic errno support.Wolfgang Denk
Needed for hash table support; probably useful in a lot of other places as well. Signed-off-by: Wolfgang Denk <wd@denx.de>
2010-09-13display_buffer: fix misaligned bufferReinhard Meyer
use a union to cause necessary alignment per architecture Signed-off-by: Reinhard Meyer <u-boot@emk-elektronik.de>
2010-08-09print_buffer: optimize & shrinkMike Frysinger
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>
2010-07-04Make sure that argv[] argument pointers are not modified.Wolfgang Denk
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>
2010-05-17Avoid use of divides in print_sizeNick Thompson
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>
2010-05-05allow print_size to print large numbers on 32-bit systemsTimur Tabi
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>
2010-05-05fix print_size printing fractional gigabyte numbers on 32-bit platformsTimur Tabi
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>
2010-04-21Move arch/ppc to arch/powerpcStefan Roese
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>
2010-04-13Move libfdt/ into lib/Peter Tyser
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>
2010-04-13Rename lib_generic/ to lib/Peter Tyser
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>