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* Fix hash table deletion to prevent lost entriesPeter Barada2011-03-22-5/+13
| | | | | | | | | | | | | | Use negative used value to mark deleted entry. Search keeps probing past deleted entries. Adding an entry uses first deleted entry when it hits end of probe chain. Initially found that "ramdiskimage" and "preboot" collide modulus 347, causing "preboot" to be inserted at idx 190, "ramdiskimage" at idx 191. Previous to this fix when "preboot" is deleted, "ramdiskimage" is orphaned. Signed-off-by: Peter Barada <peter.barada@logicpd.com> Tested-by: Wolfgang Denk <wd@denx.de>
* env: re-add support for auto-completionMike Frysinger2011-01-09-0/+20
| | | | | | | Currently, only basic completion is supported (no globs), but this is what we had previously. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
* hashtable: drop all non-reentrant versionsMike Frysinger2010-12-17-38/+2
| | | | | | | | | | | The non-reentrant versions of the hashtable functions operate on a single shared hashtable. So if two different people try using these funcs for two different purposes, they'll cause problems for the other. Avoid this by converting all existing hashtable consumers over to the reentrant versions and then punting the non-reentrant ones. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
* Coding Style cleanupWolfgang Denk2010-10-27-6/+6
| | | | Signed-off-by: Wolfgang Denk <wd@denx.de>
* lib/hashtable.c: add CONFIG_ENV_MIN_ENTRIESAndreas Bießmann2010-10-06-4/+8
| | | | | | | | | | | | | | | 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 Bießmann <andreas.devel@googlemail.com>
* New implementation for internal handling of environment variables.Wolfgang Denk2010-09-19-9/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Add hash table support as base for new environment codeWolfgang Denk2010-09-19-0/+721
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>