 |
|
| |
| aer(5) |
FreeBSD File Formats Manual |
aer(5) |
aer - aegis report script language definition
This manual entry describes the report generator script language used by the
aer(1) command. The language resembles C, with a touch of awk
and perl for flavour. It also closely resembles the appearance of
aegis' database files.
This language grew out of the need to have a general purpose
programming language to describe reports, and yet be as familiar as possible
to the people who will be using it.
This section describes the various words and symbols understood by the language.
A name is a contiguous set of alphanumeric characters, including underscore (_).
It must not start with a digit. Names may be of any length. Names are case
sensitive, so uppercase and lowercase letters are unique.
Here are some examples of names
| print |
sqrt |
if |
| how_long |
UpperCase |
dig57 |
Some words are reserved as keywords. These are the words
which appear in bold in the statement descriptions, below.
An integer constant may be decimal, any sequence of digits. Constants may be
octal, any sequence of octal digits starting with a zero. Constant may be
hexadecimal, any sequence of hexadecimal digits, starting with a
0x prefix. These are represented by the internal
long type, so significance is limited.
Here are some examples of integer constants:
| 43 |
015 |
0xbeEf |
| 2147483647 |
017777777777 |
0x7FFFFFFF |
A floating point constant has an integer part, a fraction part and an exponent
part.
Here are some examples of floating point constants:
| 1.2e3 |
4.2e+1 |
1.628e-94 |
| 0.567 |
5e6 |
.67 |
A string constant is represented as characters within double quotes (").
All characters in the script file are required to be printable, so special
characters are represented by escape sequences. These escape sequences
are:
| \" |
the " character |
| \\ |
the \ character |
| \n |
Newline |
| \f |
Form Feed |
| \r |
Carriage Return |
| \b |
Backspace |
| \t |
Horizontal Tab |
| \nnn |
octal character value |
Here are some examples of string constants:
| "Hello, World!" |
"Go away" |
"" |
| "The End0 |
"slosh is \\" |
"Say \"Please\"" |
The non‐alphanumeric characters are used to represent symbols, usually
expression operators or statement terminators. The symbols used include:
| ! |
!= |
!~ |
## |
##= |
| % |
%= |
& |
&& |
&= |
| ( |
) |
* |
** |
**= |
| *= |
+ |
++ |
+= |
, |
| - |
-- |
-= |
. |
/ |
| /= |
: |
; |
< |
<< |
| <<= |
<= |
= |
== |
> |
| >= |
>> |
>>= |
? |
[ |
| ] |
^ |
^= |
{ |
| |
| |= |
|| |
} |
~ |
~~ |
White space serves to separate words and symbols, and has no other significance.
The language is free‐form. White space includes the SPACE, TAB, FF, and
NEWLINE characters.
Comments are delimited by /* and
*/ pairs, and are treated as a single white space
character.
Statement serve to control the flow of execution of the program, or the
existence of variables.
The commonest statement consists of an expression terminated by a semicolon. The
expression is evaluated, and any result is discarded.
Examples of this statement include
x = 42;
print("Hello, World!0);
The if statement is used to conditionally execute portions of code.
Examples if the if statement include:
if (x == 42)
x = 1;
if (x * x < 1)
print("no");
else
print("yes");
The for statement has two forms. The first form is described as
for (expr1; expr2; expr3)
stmt
The expr1 is done before the loop begins. The expr2 controls, the
loop; if it does not evaluate to true the loop
terminates. The loop body is the stmt. The loop increment is done by
the expr3, and the the test is performed again.
Each of the expressions is optional; any or all may be
omitted.
Here is an example of a for loop:
for (j = 0; j < 10; ++j)
print(j);
The second form of the for statement looks like this:
for (name in keys(passwd))
print(name, passwd[name].pw_comment);
The break statement is used to break out of a loop.
Here is an example of a break statement:
for (j = 0; ; j = 2 * j + 4)
{
print(j);
if (j >= 0x800)
break;
}
The break statement works within all loop statements.
The continue statement is used to terminate the loop body and start
another repetition.
Here is an example of a continue statement:
for (j = 0; j < 1000; j = 2 * j + 4)
{
if (j < 42)
continue;
print(j);
}
The continue statement works within all loop statements.
The while statement is another loop construct. The condition is evaluated
before the loop body.
line = 0;
while (line < 7)
{
print("");
++line;
}
The do statement is another loop construct. The condition is evaluate
after the loop body.
do
print("yuck");
while
(line++ < 7);
The compound statement is a way of grouping other statements together. It
is enclosed in curly braces.
if ( lines < 7)
{
print("This\n");;
print("could\n");;
print("have\n");;
print("been\n");;
print("seven\n");;
print("blank\n");;
print("lines.\n");;
}
The auto statement is used to declare variables and initialize them to be
nul.
All user‐defined variables must be declared before they are used.
The null statement does nothing. It consists of a single semicolon. It is
most often seen as a loop body.
for (n = 0, bit = 1; n < bit_num; ++n, bit <<= 1)
;
The try catch statement is used to catch errors which would usually cause
the report to fail.
try
statement1
catch (variable)
statement2
The first statement is executed. If no error occurs, nothing else is done. If an
error occurs in the execution of the first statement the firsdt statement
execution is terminated and then the given variable is set to a description of
the error and the second statement is executed.
Expressions are much the same as in C, using the same operators. The following
table describes operator precedence and associativity:
| selection |
value . member |
| [ ] |
subscripting |
value [ expr ] |
| ( ) |
function call |
expr ( expr_list ) |
| ( ) |
grouping |
( expr ) |
| ++ |
post increment |
lvalue ++ |
| ++ |
pre increment |
++lvalue |
| -- |
post decrement |
lvalue -- |
| -- |
pre decrement |
--lvalue |
| ~ |
compliment |
~ expr |
| ! |
not |
! expr |
| - |
unary minus |
- expr |
| + |
unary plus |
+ expr |
| ** |
exponentiation |
expr ** expr |
| * |
multiply |
expr * expr |
| / |
divide |
expr / expr |
| % |
modulo (remainder) |
expr % expr |
| ~~ |
matches |
expr ~~ expr |
| !~ |
does not match |
expr !~ expr |
| in |
list member |
expr in expr |
| + |
addition (plus) |
expr + expr |
| - |
subtraction (minus) |
expr - expr |
| ## |
list and string join |
expr ## expr |
| << |
shift left |
expr << expr |
| >> |
shift right |
expr >> expr |
| < |
less than |
expr < expr |
| <= |
less than or equal |
expr <= expr |
| > |
greater than |
expr > expr |
| >= |
greater than or equal |
expr >= expr |
| == |
equal |
expr == expr |
| != |
not equal |
expr != expr |
| & |
bitwise AND |
expr & expr |
| ^ |
bitwise exclusive OR |
expr ^ expr |
| | |
bitwise inclusive OR |
expr | expr |
| ? : |
arithmetic if |
expr ? expr : expr |
| = |
simple assignment |
expr = expr |
| *= |
multiply and assign |
expr *= expr |
| /= |
divide and assign |
expr /= expr |
| %= |
modulo and assign |
expr %= expr |
| += |
add and assign |
expr += expr |
| -= |
subtract and assign |
expr -= expr |
| <<= |
shift left and assign |
expr <<= expr |
| >>= |
shift right and assign |
expr >>= expr |
| &= |
AND and assign |
expr &= expr |
| ^= |
exclusive OR and assign |
expr ^= expr |
| |= |
inclusive OR and assign |
expr |= expr |
| , |
comma (sequencing) |
expr , expr |
Most of these operators behave as they do in C, but some of these
operators will require some explanation.
The ** operator raises the left argument to the right'th
power. It is right associative.
The ~~ operator compares two strings. It returns a
number between 0.0 and 1.0. Zero means completely different, one means
identical. Case is significant.
The !~ is used to compare two strings, and returns the
opposite of the ~~ operator; one if completely
different, and zero if identical.
The ## operator is used to join two strings together.
There are several types used within the report language.
- array
- Values of this type contain other values, indexed by a string. If you
attempt to index by an arithmetic type, it will be silently converted to a
string. Use the keys function to determine all of the keys; use the
count function to determine how many entries an array has. The type
of an array element is not restricted, only the index must be a
string.
- boolean
- This type has two values: true and
false. These value arise from the boolean
operators described earlier.
- integer
- This type is represented by the long C type. It has a limited range
of values (usually -2e9 to 2e9 approximately). If used in a string
context, it will be silently converted to a string. For exact control of
the format, used the sprintf function.
- list
- Values of this type contain a list of other values. The type of these
values is not restricted. The array index operator (e[e]) may be used to
access list elements; indexes start at zero (0).
- string
- Values of this type are an arbitrary string of C characters, except the
NUL character ( ). Strings may be of any length.
- struct
- Values of this type contain additional values. These values are accessed
using the "dot" operator. These values may also be treated as if
they were arrays.
- real
- This type is represented the the double C type. If used in a string
context, it will be silently converted to a string. For exact control of
the format, used the sprintf function.
There are a number of built‐in functions.
- basename
- This function is used to extract the last element from a file path.
- capitalize
- This function converts it argument to a capitalized string in Title
Case.
- ceil
- This function is used to round a number to an integer, towards positive
infinity.
- change_number
- This function is used to determine the change number. It may be set by the
-Change command line option, or it may default. The return value is
an integer.
- change_number_set
- This function maybe used to determine if the change number was set by the
-Change command line option. The return value is a boolean.
- columns
- This function is used to define the report columns. Each argument is a
structure containing some or all of the following fields:
| left |
the left margin, counting characters from 0 on the left |
| right |
the right margin, plus one |
| width |
the width in characters, defaults to 7 if right not specified |
| padding |
white space between columns, defaults to 1 if not set |
| title |
the title for this column, separate multiple lines with \n |
The columns must be defined before the print function is used.
- count
- This function is used to count the number of elements in a list or
array.
- dirname
- This function is used to extract all but the last element from a file
path.
- downcase
- This functions converts its argument to lower case.
- eject
- This function is used to start a new page of output.
- floor
- This function is used to round a number to an integer, towards negative
infinity.
- getenv
- This function is used to get the value of an environment variable. Will
return the empty string if not set.
- gettime
- This function is used to parse a string to produce a time. It understands
a variety of different date formats.
- getuid
- This function takes no arguments, and returns the user ID of the process
which invoked the report generator. The return value is an integer.
- keys
- This function may be given an array or a list as argument. It returns a
list of keys which may be used to index the argument. Most often seen in
for loops.
- length
- This function is used to find the length of a string.
- mktime
- This a synonym for the gettime function.
- mtime
- This function may be used to obtain the modification time of a file.
- need
- This function is used to insert a page break into the report if the
required number of lines is not available before the end of page. If
sufficient lines are available, only a single blank line will be inserted.
The return value is void.
- now
- This function takes no arguments, and returns the current time.
- page_length
- This function may be used to determine the length of the output page in
lines. The return value is an integer.
- page_width
- This function may be used to determine the width of the output page in
columns. The return value is an integer.
- print
- This function is used to print into the defined columns. Columns will wrap
around.
- project_name
- This function is used to determine the project name. It may be set by the
-Project command line option, or it may default. The return value
is a string.
- project_name_set
- This function maybe used to determine if the project name was set by the
-Project command line option. The return value is a boolean.
- quote_html
- This function quotes its argument string to insulate HTML special
characters; these include “less than”
(<), “ampersand”
(&) and non‐printing characters. This is most often used
to generate suitable text for web pages.
- quote_tcl
- This function quotes its argument string to insulate TCL special
characters; these include “[]” and non‐printing
characters. This is most often used to generate suitable text for TCL
interface scripts.
- quote_url
- This function quotes its argument string to insulate URL special
characters; these include “?+#:&=” and
non‐printing characters. This is most often used to generate
suitable text for web pages.
- round
- This function is used to round a number to an integer, towards the closest
integer.
- sort
- This function must be given a list as argument. The values are sorted into
ascending order. A new list is returned.
- split
- This function is used to split a string into a list of strings. The first
argument is the string to split, the second argument is the character to
split around.
- sprintf
- This function is used to build strings. It is similar to the
sprintf(3) function.
- strftime
- This function is used to format times as strings. The first argument is
the format string, the second argument is a time. See the
strftime(3) man page for more the format specifiers.
- subst
- This function is used to substitute strings by regular expression. The
first argument is the pattern to match, the second argument is the
substitution pattern, the third argument is the input string to be
substituted. The option fourth argument is the number of substitutions to
perform; the default is as many as possible.
- substr
- This function is used to extract substrings from strings. The first
argument is a string, the second argument is the starting position,
starting from 0, and the third argument is the length.
- terse
- This function may be used to determine of the -TERse command line
option was used. The return type is a boolean.
- title
- This function is used to set the title of the report. It takes at most two
arguments, one for each available title line.
- trunc
- This function is used to round a number to an integer, towards zero.
- typeof
- This function is used to determine the type of a value. The return type is
a string containing the name of the type, as described in the
- unquote_url
- This function will remove URL quoting from the argument string. URL
quoting takes the form of a percent sign (%) followed by two hex digits.
This is replaced by a single character with the value represented by the
hex digits.
- upcase
- This functions converts its argument to upper case.
- working_days
- This function is used to determine the number of working days between two
times.
- wrap
- This function is used to wrap a string into a list of strings. The first
argument is the wring to wrap, the second argument is the maxmium width of
the output strings.
- wrap_html
- This function is used to wrap a string into a list of strings. The first
argument is the wring to wrap, the second argument is the maxmium width of
the output strings. This is very similar to the wrap functions,
except thatit inserts HTML paragraph breaks <p> or line breaks
<br> to reflect the newlines within the string (2 or 1,
respectively). TYPES section.
There are a number of built‐in variables.
- arg
- This variable is a list containing the arguments passed on the
aer(1) command line.
- change
There is a special type of variable created by using an
expression similar to project[project_name()].state.change[n] which
contains all of the fields described in aecstate (5), plus some extras:
- change
- Branches have a change array, just like project below.
- change_number
- The number of the change.
- config
- This gives access to all of the fields described in
aepconf(5).
- project_name
- The name of the project containing the change.
- src
- This gives access to the change files, and when indexed by file name,
yields a value conataining fields as described in aefstate(5), for
the src field.
- group
- This variable is an array containing all of the entries in the
/etc/group file. Each entry is a structure with fields as
documented in the group(5) manual entry. The gr_mem element
is a list of strings. This array may be indexed by either a string,
treated as a group name, or by an integer, treated as a GID.
- passwd
- This variable is an array containing all of the entries in the
/etc/passwd file. Each entry is a structure with fields as
documented in the passwd(5) manual entry. This array may be indexed
by either a string, treated as a user name, or by an integer, treated as a
uid.
- project
- This variable is an array containing one entry for each aegis project,
indexed by name. Each array element is a structure, containing
| name |
the project name |
| directory |
the root of the project directory tree |
| state |
the project state |
The project state contains the fields documented in the aepstate(5)
manual entry. Except: the change field is not a list of change
numbers, it is an array indexed by change number of change states, as
documented in the aecstate(5) manual entry. (See change,
above.)
- user
- This variable is an array containing the .aegisrc file of each
user. Each entry is a structure with fields as documented in the
aeuconf(5) manual entry. This array may be indexed by either a
string, treated as a user name, or by an integer, treated as a uid. Files
which are unreadable or absent will generate an error, so you need to wrap
accesses in a try/catch statement. (Note: count()
and keys() functions think the array is empty; if
you want a list of users, consult the passwd
array.)
The reports are kept in the /usr/local/share/report directory. The
reports are associated with a name by the /usr/local/share/report.index
file. Their names use the command line argument abbreviation scheme, so that
report names may be abbreviated.
- aer(1)
- report generator
- aecstate(5)
- change state description
- aepstate(5)
- project state description
- aerptidx(5)
- report index file format
aegis version 4.25.D510
Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 Peter Miller
The aegis program comes with ABSOLUTELY NO WARRANTY; for details
use the 'aegis -VERSion License' command. This is free software and
you are welcome to redistribute it under certain conditions; for details use
the 'aegis -VERSion License' command.
| Peter Miller |
E‐Mail: |
pmiller@opensource.org.au |
| /\/\* |
WWW: |
http://miller.emu.id.au/pmiller/ |
 Visit the GSP FreeBSD Man Page Interface.
Output converted with ManDoc.
|
