NAME
aepatch - send and receive changes as patches
SYNOPSIS
aepatch -send [ option... ]
aepatch -receive [ option... ]
aepatch -list [ option... ]
aepatch -Help
aepatch -VERSion
DESCRIPTION
The aepatch command is used to send Aegis changes as patches, or
receive patches and turn them into Aegis changes.
Please note that this only works for text files. If your project uses
binary files, the aepatch program will not be useful because the
diff(1) and patch(1) commands only work on text files. Also, this only
works for files with names which do not contain white space.
If you need to merge matches together, you could use the GNU patch
utils, which include a tool to merge patches together.
SEND
The send variant takes a specified change and constructs a patch
containing all of the changes to all of the files in that change. The
result is compressed, and encoded into a text format which can be sent
as e-mail without being corrupted by the mail transfer agents along the
way.
The output of the aepatch -send command is a normal Unix patch, as you
would produce using diff(1), bzip2(1) and a MIME encoder such as
mpack(1). There are no special formats. The output can be
uncompressed with the normal bunzip2(1) command and applied with the
normal patch(1) command.
The compression algorithm is selectable via the -compression-algorithm
option, see the OPTIONS section, below, for details. The
-compatibility option also understands compression needs.
Generating Traditional Patches
If you wish to send "traditional" patches to developers who are not
using Aegis to manage the sources at their end, you can use the
following options:
aepatch -send -cte=none -comp-alg=none
This says to use no Content Transfer Encoding, and no compression. If
you wish to also omit the Aegis meta data, you can use the following
options:
aepatch -send -cte=none -nocomp -compat=4.16
This setting for the -compatibility option omits all Aegis extensions.
By default, a context diff is generated. Some projects prefer to use
the unified diff format. This is controlled by the patch_diff_command
field of the project configuration file (see aepconf(5) for more
information). If you have GNU diff, use the following command:
patch_diff_command = "set +e; "
"diff -u --text "
"-L ${quote $index} -L ${quote $index} "
"${quote $original} ${quote $input} > ${quote $output}; "
"test $? -le 1"";
This setting will cause the aepatch(1) command to produce unified diff
patches instead of context diff patches. As you can see from this
command, the aepatch(1) command is onlu of use if you have text source
files; it produces less than ideal results for binary files.
Options
The following options are understood by the send variant:
-Change number
This option may be used to specify a particular change within a
project. See aegis(1) for a complete description of this
option.
-COMPATibility version-number
This option may be used to specify the version of aepatch(1)
which will be receiving this change set. This information is
used to select which features to include in the data, and which
to omit. By default, the latest feature set will be used.
-compression-algorithm name
This option may be used to specify the compression to be used.
They are listed on order of compression effeciency.
none Use no compression (not always meaningful for all
commands).
gzip Use the compression used by the gzip(1) program.
bzip2 Use the compression used by the bzip2(1) program.
More compression algorithms may be added in the future.
-COMPress
This option is deprecated in favour of the -comp-alg=gzip or
-comp-alg=bzip2 options.
-No_COMPress
This options is deprecated in favour of the -comp-alg=none
option.
-Content_Transfer_Encoding name
This option may be used to specify the content transfer
encoding to be used. It may take one of the following values:
None No content transfer encoding is to be performed.
Base64 The MIME base 64 encoding is to be used. This is the
default.
Quoted_Printable
The MIME quoted printable encoding is to be used.
Unix_to_Unix_encode
The ancient unix-to-unix encoding is to be used.
These encodings may be abbreviated in the same way as comment
line options.
-Ascii_Armor
This means the same as the “-cte=base64” option above.
-No_Ascii_Armor
This means the same as the “-cte=none” option above.
-DELta number
This option may be used to specify a particular delta in the
project’s history to copy the file from, rather than the most
current version. If the delta has been given a name (see
aedn(1) for how) you may use a delta name instead of a delta
number. It is an error if the delta specified does not exist.
Delta numbers start from 1 and increase; delta 0 is a special
case meaning “when the branch started”.
-DELta_Date string
This option may be used to specify a particular date and time
in the project’s history to copy the file from, rather than the
most current version. It is an error if the string specified
cannot be interpreted as a valid date and time. Quote the
string if you need to use spaces.
-DELta_From_Change number
This option may be used to specify a particular project delta
from its change number.
-Output filename
This option may be used to specify the output file. The output
is sent to the standard output by default.
-Project name
This option may be used to select the project of interest.
When no -Project option is specified, the AEGIS_PROJECT
environment variable is consulted. If that does not exist, the
user’s $HOME/.aegisrc file is examined for a default project
field (see aeuconf(5) for more information). If that does not
exist, when the user is only working on changes within a single
project, the project name defaults to that project. Otherwise,
it is an error.
-Signed_Off_By
This option may be used to have a Signed-off-by: line appended
to the change set description.
-No_Signed_Off_By
This option may be used to prevent a Signed-off-by: line from
being appended to the change set description.
RECEIVE
The receive variant takes a patch and creates an Aegis change (see
aenc(1)) to implement the change within. Files are added to the change
(see aenf(1), aecp(1), aerm(1), aent(1)) and then the patch contents
are unpackaged into the development directory, and the changes applied
to the files.
The patch does not have to be produced by the aepatch(1) command.
Normal patches produced by diff(1) command are also valid input. The
intent is that you can particicate in normal open source development,
and also use Aegis, even if your fellow developers are not.
Once unpacked, the change is then built (see aeb(1)), differenced (see
aed(1)), and tested (see aet(1)). The automatic process stops at this
point, so that you can confirm that the change is desired.
File Names
It is common for patch files generated using the usual diff -r
mechanism to contain extra path prefixes. The aepatch(1) command
attempts to remove these automagically. This is usually possible
because patches usually modify files within the project, so the patch
file names are compared with project file names to guess which and how
much path prefixes to remove.
-Remove_Path_Prefix string
This option may be used to explicitly specify path prefixes to
be removed, if present. It may be specified more than once.
If you have a complex project directory structure, from time to time
people may send you patches relative to a sub-directory, rather than
relative to the project root. The aepatch(1) program can’t guess this
by itself.
-Add_Path_Prefix string
This option may be used to specify the path of a project sub-
directory in which to apply the patch.
Notification
The aepatch command invokes various other Aegis commands. The usual
notifications that these commands would issue are issued.
Options
The following options are understood by the receive variant:
-Change number
This option may be used to choose the change number to be used,
otherwise the change number in the patch (if present) will be
used if it is available, otherwise one will be chosen
automatically.
-DELta number
This option may be used to specify a particular delta in the
project’s history to copy the file from, just as for the
aecp(1) command. You may also use a delta name instead of a
delta number.
-DIRectory path
This option may be used to specify which directory is to be
used. It is an error if the current user does not have
appropriate permissions to create the directory path given.
This must be an absolute path.
Caution: If you are using an automounter do not use ‘pwd‘ to
make an absolute path, it usually gives the wrong answer.
-File filename
Read the change set from the specified file. The default is to
read it from the standard input. The filename ‘-’ is
understood to mean the standard input.
If your system has libcurl(3), and Aegis was configured to use
it at compile time (this is the default if it is available) you
will also be able to specify a Uniform Resource Locator (URL)
in place of the file name. The relevant data will be
downloaded. (The -Verbose option will provide a progress bar.)
-Project name
This option may be used to set the project name. If not
specified the project name in the input package will be used
(if present), otherwise the usual project name default will be
used.
-Trojan This option may be used to treat the change set as if it had a
Trojan horse attack in it.
-No_Trojan
This option may be used to treat the change set as if it
definitely does not have a Trojan horse attack in it. Use with
extreme care. You need to have authenticated the message with
something like PGP first and know the the author well.
Security
Receiving changes by e-mail, and automatically committing them to the
baseline without checking them, would be a recipe for disaster. A
number of safeguards are provided:
· The format of the package is confirmed to be correct, and the package
verified for internal consistency, before it is unpacked and acted
upon.
· The automatic portion of the process stops before development ends.
This ensures that the receiver validates the change before it is
committed, and then it must also be reviewed, preventing accidental
or malicious damage.
· The more you use Aegis’ test management facilities (see aent(1) and
aet(1)) the harder it is for an inadequate change to get into the
baseline.
LIST
The list variant can be used to list the contents of a package without
actually unpacking it first. The output is reminiscent of the aegis
-list change-details output.
Options
The following options are understood by the list variant:
-File filename
Read the change set from the specified file. The default is to
read it from the standard input. The filename ‘-’ is
understood to mean the standard input.
If your system has libcurl(3), and Aegis was configured to use
it at compile time (this is the default if it is available) you
will also be able to specify a Uniform Resource Locator (URL)
in place of the file name. The relevant data will be
downloaded. (The -Verbose option will provide a progress bar.)
-Output filename
This option may be used to specify the output file. The output
is sent to the standard output by default. Only useful with
the -List option.
OPTIONS
The following options to this command haven’t been mentioned yet:
-Help
This option may be used to obtain more information about how to
use the aepatch program.
See also aegis(1) for options common to all aegis commands.
All options may be abbreviated; the abbreviation is documented as the
upper case letters, all lower case letters and underscores (_) are
optional. You must use consecutive sequences of optional letters.
All options are case insensitive, you may type them in upper case or
lower case or a combination of both, case is not important.
For example: the arguments "-project, "-PROJ" and "-p" are all
interpreted to mean the -Project option. The argument "-prj" will not
be understood, because consecutive optional characters were not
supplied.
Options and other command line arguments may be mixed arbitrarily on
the command line, after the function selectors.
The GNU long option names are understood. Since all option names for
aepatch are long, this means ignoring the extra leading ’-’. The
"--option=value" convention is also understood.
FILE FORMAT
The file format re-uses existing formats, rather than introduce
anything new. This means it is possible to extract the contents of a
package even when aepatch is unavailable.
· On sending, the source files are generated using the diff(1) program,
in the same way a normal Unix patch is generated.
On receiving, the differences are applied to the source files, in the
same manner as the normal patch(1) program.
· On sending, the patch is compressed using the GNU gzip format.
Typically primary source files are ASCII text, resulting in
significant compression. (This is optional.)
On receiving, if the patch is compressed it will be automagically
uncompressed, detection is automatic, you do not need to do this
yourself.
· On sending, the compressed patch is encoded using the MIME base64
encoding. This makes the result approximately 33% larger than the
compressed binary would be, but still smaller than the primary
sources. (This is optional.)
On receiving, if the patch is MIME64 encoded it will be automatically
decoded, detetcion is automatic, you do not need to do this yourself.
EXIT STATUS
The aepatch command will exit with a status of 1 on any error. The
aepatch command will only exit with a status of 0 if there are no
errors.
ENVIRONMENT VARIABLES
See aegis(1) for a list of environment variables which may affect this
command. See aepconf(5) for the project configuration file’s project_
specific field for how to set environment variables for all commands
executed by Aegis.
COPYRIGHT
aepatch version 4.24.3.D001
Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Peter
Miller
The aepatch program comes with ABSOLUTELY NO WARRANTY; for details use
the ’aepatch -VERSion License’ command. This is free software and you
are welcome to redistribute it under certain conditions; for details
use the ’aepatch -VERSion License’ command.
AUTHOR
Peter Miller E-Mail: millerp@canb.auug.org.au
/\/\* WWW: http://www.canb.auug.org.au/~millerp/