Fixed lots of issues with installing a low-caps version of fshell from SIS file.
* Fixed issue in CCommandFactory whereby some APIs like GetCommandInfoL could trigger allocations on the wrong heap or signals to the wrong thread. The symptoms were often seen as a crash in the which_00 thread when running ciftest.
* Lots of build fixes for when FSHELL_PROTECTED_UIDS isn't defined and when all capabilities aren't available.
* Added new platform.mmh macro FSHELL_OPEN_SIGNED.
* Open signing of fshell SIS files is now supported for production S60 handsets. Build fshell with the FSHELL_OPEN_SIGNED macro defined (and without defining FSHELL_CAP_ALL or FSHELL_PROTECTED_UIDS) in your platform.mmh and submit \epoc32\fshell\fshell.unsigned.sis to https://www.symbiansigned.com/app/page/public/openSignedOnline.do . The following commands are not available when using Open Signing due to Platform Security restrictions: fdb; kerninfo; chunkinfo; svrinfo; objinfo; sudo; fsck; localdrive; ramdefrag; readmem; reboot; setcritical; setpriority. Others such as chkdeps, e32header, ps, and fshell itself will run but in a restricted capacity (for example, fshell will no longer allow you to modify files in the \sys\bin directory).
* Removed commands objinfo, svrinfo, chunkinfo, readmem, fsck completely when memory access isn't present - previously they would still appear in the help but would give an error if you tried to run them.
<html>
<head>
<title>pcrecallout specification</title>
</head>
<body bgcolor="#FFFFFF" text="#00005A" link="#0066FF" alink="#3399FF" vlink="#2222BB">
<h1>pcrecallout man page</h1>
<p>
Return to the <a href="index.html">PCRE index page</a>.
</p>
<p>
This page is part of the PCRE HTML documentation. It was generated automatically
from the original man page. If there is any nonsense in it, please consult the
man page, in case the conversion went wrong.
<br>
<ul>
<li><a name="TOC1" href="#SEC1">PCRE CALLOUTS</a>
<li><a name="TOC2" href="#SEC2">MISSING CALLOUTS</a>
<li><a name="TOC3" href="#SEC3">THE CALLOUT INTERFACE</a>
<li><a name="TOC4" href="#SEC4">RETURN VALUES</a>
<li><a name="TOC5" href="#SEC5">AUTHOR</a>
<li><a name="TOC6" href="#SEC6">REVISION</a>
</ul>
<br><a name="SEC1" href="#TOC1">PCRE CALLOUTS</a><br>
<P>
<b>int (*pcre_callout)(pcre_callout_block *);</b>
</P>
<P>
PCRE provides a feature called "callout", which is a means of temporarily
passing control to the caller of PCRE in the middle of pattern matching. The
caller of PCRE provides an external function by putting its entry point in the
global variable <i>pcre_callout</i>. By default, this variable contains NULL,
which disables all calling out.
</P>
<P>
Within a regular expression, (?C) indicates the points at which the external
function is to be called. Different callout points can be identified by putting
a number less than 256 after the letter C. The default value is zero.
For example, this pattern has two callout points:
<pre>
(?C1)abc(?C2)def
</pre>
If the PCRE_AUTO_CALLOUT option bit is set when <b>pcre_compile()</b> is called,
PCRE automatically inserts callouts, all with number 255, before each item in
the pattern. For example, if PCRE_AUTO_CALLOUT is used with the pattern
<pre>
A(\d{2}|--)
</pre>
it is processed as if it were
<br>
<br>
(?C255)A(?C255)((?C255)\d{2}(?C255)|(?C255)-(?C255)-(?C255))(?C255)
<br>
<br>
Notice that there is a callout before and after each parenthesis and
alternation bar. Automatic callouts can be used for tracking the progress of
pattern matching. The
<a href="pcretest.html"><b>pcretest</b></a>
command has an option that sets automatic callouts; when it is used, the output
indicates how the pattern is matched. This is useful information when you are
trying to optimize the performance of a particular pattern.
</P>
<br><a name="SEC2" href="#TOC1">MISSING CALLOUTS</a><br>
<P>
You should be aware that, because of optimizations in the way PCRE matches
patterns, callouts sometimes do not happen. For example, if the pattern is
<pre>
ab(?C4)cd
</pre>
PCRE knows that any matching string must contain the letter "d". If the subject
string is "abyz", the lack of "d" means that matching doesn't ever start, and
the callout is never reached. However, with "abyd", though the result is still
no match, the callout is obeyed.
</P>
<br><a name="SEC3" href="#TOC1">THE CALLOUT INTERFACE</a><br>
<P>
During matching, when PCRE reaches a callout point, the external function
defined by <i>pcre_callout</i> is called (if it is set). This applies to both
the <b>pcre_exec()</b> and the <b>pcre_dfa_exec()</b> matching functions. The
only argument to the callout function is a pointer to a <b>pcre_callout</b>
block. This structure contains the following fields:
<pre>
int <i>version</i>;
int <i>callout_number</i>;
int *<i>offset_vector</i>;
const char *<i>subject</i>;
int <i>subject_length</i>;
int <i>start_match</i>;
int <i>current_position</i>;
int <i>capture_top</i>;
int <i>capture_last</i>;
void *<i>callout_data</i>;
int <i>pattern_position</i>;
int <i>next_item_length</i>;
</pre>
The <i>version</i> field is an integer containing the version number of the
block format. The initial version was 0; the current version is 1. The version
number will change again in future if additional fields are added, but the
intention is never to remove any of the existing fields.
</P>
<P>
The <i>callout_number</i> field contains the number of the callout, as compiled
into the pattern (that is, the number after ?C for manual callouts, and 255 for
automatically generated callouts).
</P>
<P>
The <i>offset_vector</i> field is a pointer to the vector of offsets that was
passed by the caller to <b>pcre_exec()</b> or <b>pcre_dfa_exec()</b>. When
<b>pcre_exec()</b> is used, the contents can be inspected in order to extract
substrings that have been matched so far, in the same way as for extracting
substrings after a match has completed. For <b>pcre_dfa_exec()</b> this field is
not useful.
</P>
<P>
The <i>subject</i> and <i>subject_length</i> fields contain copies of the values
that were passed to <b>pcre_exec()</b>.
</P>
<P>
The <i>start_match</i> field normally contains the offset within the subject at
which the current match attempt started. However, if the escape sequence \K
has been encountered, this value is changed to reflect the modified starting
point. If the pattern is not anchored, the callout function may be called
several times from the same point in the pattern for different starting points
in the subject.
</P>
<P>
The <i>current_position</i> field contains the offset within the subject of the
current match pointer.
</P>
<P>
When the <b>pcre_exec()</b> function is used, the <i>capture_top</i> field
contains one more than the number of the highest numbered captured substring so
far. If no substrings have been captured, the value of <i>capture_top</i> is
one. This is always the case when <b>pcre_dfa_exec()</b> is used, because it
does not support captured substrings.
</P>
<P>
The <i>capture_last</i> field contains the number of the most recently captured
substring. If no substrings have been captured, its value is -1. This is always
the case when <b>pcre_dfa_exec()</b> is used.
</P>
<P>
The <i>callout_data</i> field contains a value that is passed to
<b>pcre_exec()</b> or <b>pcre_dfa_exec()</b> specifically so that it can be
passed back in callouts. It is passed in the <i>pcre_callout</i> field of the
<b>pcre_extra</b> data structure. If no such data was passed, the value of
<i>callout_data</i> in a <b>pcre_callout</b> block is NULL. There is a
description of the <b>pcre_extra</b> structure in the
<a href="pcreapi.html"><b>pcreapi</b></a>
documentation.
</P>
<P>
The <i>pattern_position</i> field is present from version 1 of the
<i>pcre_callout</i> structure. It contains the offset to the next item to be
matched in the pattern string.
</P>
<P>
The <i>next_item_length</i> field is present from version 1 of the
<i>pcre_callout</i> structure. It contains the length of the next item to be
matched in the pattern string. When the callout immediately precedes an
alternation bar, a closing parenthesis, or the end of the pattern, the length
is zero. When the callout precedes an opening parenthesis, the length is that
of the entire subpattern.
</P>
<P>
The <i>pattern_position</i> and <i>next_item_length</i> fields are intended to
help in distinguishing between different automatic callouts, which all have the
same callout number. However, they are set for all callouts.
</P>
<br><a name="SEC4" href="#TOC1">RETURN VALUES</a><br>
<P>
The external callout function returns an integer to PCRE. If the value is zero,
matching proceeds as normal. If the value is greater than zero, matching fails
at the current point, but the testing of other matching possibilities goes
ahead, just as if a lookahead assertion had failed. If the value is less than
zero, the match is abandoned, and <b>pcre_exec()</b> (or <b>pcre_dfa_exec()</b>)
returns the negative value.
</P>
<P>
Negative values should normally be chosen from the set of PCRE_ERROR_xxx
values. In particular, PCRE_ERROR_NOMATCH forces a standard "no match" failure.
The error number PCRE_ERROR_CALLOUT is reserved for use by callout functions;
it will never be used by PCRE itself.
</P>
<br><a name="SEC5" href="#TOC1">AUTHOR</a><br>
<P>
Philip Hazel
<br>
University Computing Service
<br>
Cambridge CB2 3QH, England.
<br>
</P>
<br><a name="SEC6" href="#TOC1">REVISION</a><br>
<P>
Last updated: 29 May 2007
<br>
Copyright © 1997-2007 University of Cambridge.
<br>
<p>
Return to the <a href="index.html">PCRE index page</a>.
</p>