File tidies, version updates, etc. for 10.21-RC1

This commit is contained in:
Philip.Hazel 2015-12-17 18:44:06 +00:00
parent 293da188aa
commit dffd559601
48 changed files with 1726 additions and 1357 deletions

41
NEWS
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@ -1,6 +1,47 @@
News about PCRE2 releases
-------------------------
Version 10.21 15-December-2015
------------------------------
1. Many bugs have been fixed. A large number of them were provoked only by very
strange pattern input, and were discovered by fuzzers. Some others were
discovered by code auditing. See ChangeLog for details.
2. The Unicode tables have been updated to Unicode version 8.0.0.
3. For Perl compatibility in EBCDIC environments, ranges such as a-z in a
class, where both values are literal letters in the same case, omit the
non-letter EBCDIC code points within the range.
4. There have been a number of enhancements to the pcre2_substitute() function,
giving more flexibility to replacement facilities. It is now also possible to
cause the function to return the needed buffer size if the one given is too
small.
5. The PCRE2_ALT_VERBNAMES option causes the "name" parts of special verbs such
as (*THEN:name) to be processed for backslashes and to take note of
PCRE2_EXTENDED.
6. PCRE2_INFO_HASBACKSLASHC makes it possible for a client to find out if a
pattern uses \C, and --never-backslash-C makes it possible to compile a version
PCRE2 in which the use of \C is always forbidden.
7. A limit to the length of pattern that can be handled can now be set by
calling pcre2_set_max_pattern_length().
8. When matching an unanchored pattern, a match can be required to begin within
a given number of code units after the start of the subject by calling
pcre2_set_offset_limit().
9. The pcre2test program has been extended to test new facilities, and it can
now run the tests when LF on its own is not a valid newline sequence.
10. The RunTest script has also been updated to enable more tests to be run.
11. There have been some minor performance enhancements.
Version 10.20 30-June-2015
--------------------------

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@ -11,16 +11,16 @@ dnl be defined as -RC2, for example. For real releases, it should be empty.
m4_define(pcre2_major, [10])
m4_define(pcre2_minor, [21])
m4_define(pcre2_prerelease, [-RC1])
m4_define(pcre2_date, [2015-07-06])
m4_define(pcre2_date, [2015-12-15])
# NOTE: The CMakeLists.txt file searches for the above variables in the first
# 50 lines of this file. Please update that if the variables above are moved.
# Libtool shared library interface versions (current:revision:age)
m4_define(libpcre2_8_version, [2:0:2])
m4_define(libpcre2_16_version, [2:0:2])
m4_define(libpcre2_32_version, [2:0:2])
m4_define(libpcre2_posix_version, [0:0:0])
m4_define(libpcre2_8_version, [3:0:3])
m4_define(libpcre2_16_version, [3:0:3])
m4_define(libpcre2_32_version, [3:0:3])
m4_define(libpcre2_posix_version, [0:1:0])
AC_PREREQ(2.57)
AC_INIT(PCRE2, pcre2_major.pcre2_minor[]pcre2_prerelease, , pcre2)

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@ -42,19 +42,20 @@ request are as follows:
PCRE2_BSR_ANYCRLF: CR, LF, or CRLF only
PCRE2_INFO_CAPTURECOUNT Number of capturing subpatterns
PCRE2_INFO_FIRSTBITMAP Bitmap of first code units, or NULL
PCRE2_INFO_FIRSTCODEUNIT First code unit when type is 1
PCRE2_INFO_FIRSTCODETYPE Type of start-of-match information
0 nothing set
1 first code unit is set
2 start of string or after newline
PCRE2_INFO_FIRSTCODEUNIT First code unit when type is 1
PCRE2_INFO_HASBACKSLASHC Return 1 if pattern contains \C
PCRE2_INFO_HASCRORLF Return 1 if explicit CR or LF matches
exist in the pattern
PCRE2_INFO_JCHANGED Return 1 if (?J) or (?-J) was used
PCRE2_INFO_JITSIZE Size of JIT compiled code, or 0
PCRE2_INFO_LASTCODEUNIT Last code unit when type is 1
PCRE2_INFO_LASTCODETYPE Type of must-be-present information
0 nothing set
1 code unit is set
PCRE2_INFO_LASTCODEUNIT Last code unit when type is 1
PCRE2_INFO_MATCHEMPTY 1 if the pattern can match an
empty string, 0 otherwise
PCRE2_INFO_MATCHLIMIT Match limit if set,
@ -62,8 +63,8 @@ request are as follows:
PCRE2_INFO_MAXLOOKBEHIND Length (in characters) of the longest
lookbehind assertion
PCRE2_INFO_MINLENGTH Lower bound length of matching strings
PCRE2_INFO_NAMEENTRYSIZE Size of name table entries
PCRE2_INFO_NAMECOUNT Number of named subpatterns
PCRE2_INFO_NAMEENTRYSIZE Size of name table entries
PCRE2_INFO_NAMETABLE Pointer to name table
PCRE2_CONFIG_NEWLINE Code for the newline sequence:
PCRE2_NEWLINE_CR

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@ -70,6 +70,9 @@ The options are:
PCRE2_UTF was set at compile time)
PCRE2_SUBSTITUTE_EXTENDED Do extended replacement processing
PCRE2_SUBSTITUTE_GLOBAL Replace all occurrences in the subject
PCRE2_SUBSTITUTE_OVERFLOW_LENGTH If overflow, compute needed length
PCRE2_SUBSTITUTE_UNKNOWN_UNSET Treat unknown group as unset
PCRE2_SUBSTITUTE_UNSET_EMPTY Simple unset insert = empty string
</pre>
The function returns the number of substitutions, which may be zero if there
were no matches. The result can be greater than one only when

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@ -716,8 +716,8 @@ of the following match-time parameters:
<pre>
A callout function
The offset limit for matching an unanchored pattern
The limit for calling <i>match()</i>
The limit for calling <i>match()</i> recursively
The limit for calling <b>match()</b> (see below)
The limit for calling <b>match()</b> recursively
</pre>
A match context is also required if you are using custom memory management.
If none of these apply, just pass NULL as the context argument of
@ -771,7 +771,9 @@ PCRE2_USE_OFFSET_LIMIT is not set, an error is generated.
<P>
The offset limit facility can be used to track progress when searching large
subject strings. See also the PCRE2_FIRSTLINE option, which requires a match to
start within the first line of the subject.
start within the first line of the subject. If this is set with an offset
limit, a match must occur in the first line and also within the offset limit.
In other words, whichever limit comes first is used.
<b>int pcre2_set_match_limit(pcre2_match_context *<i>mcontext</i>,</b>
<b> uint32_t <i>value</i>);</b>
<br>
@ -1212,7 +1214,9 @@ built.
If this option is set, an unanchored pattern is required to match before or at
the first newline in the subject string, though the matched text may continue
over the newline. See also PCRE2_USE_OFFSET_LIMIT, which provides a more
general limiting facility.
general limiting facility. If PCRE2_FIRSTLINE is set with an offset limit, a
match must occur in the first line and also within the offset limit. In other
words, whichever limit comes first is used.
<pre>
PCRE2_MATCH_UNSET_BACKREF
</pre>
@ -1563,11 +1567,10 @@ are as follows:
Return a copy of the pattern's options. The third argument should point to a
<b>uint32_t</b> variable. PCRE2_INFO_ARGOPTIONS returns exactly the options that
were passed to <b>pcre2_compile()</b>, whereas PCRE2_INFO_ALLOPTIONS returns
the compile options as modified by any top-level option settings at the start
of the pattern itself. In other words, they are the options that will be in
force when matching starts. For example, if the pattern /(?im)abc(?-i)d/ is
compiled with the PCRE2_EXTENDED option, the result is PCRE2_CASELESS,
PCRE2_MULTILINE, and PCRE2_EXTENDED.
the compile options as modified by any top-level option settings such as (*UTF)
at the start of the pattern itself. For example, if the pattern /(*UTF)abc/ is
compiled with the PCRE2_EXTENDED option, the result is PCRE2_EXTENDED and
PCRE2_UTF.
</P>
<P>
A pattern compiled without PCRE2_ANCHORED is automatically anchored by PCRE2 if
@ -1609,18 +1612,27 @@ matches only CR, LF, or CRLF.
<pre>
PCRE2_INFO_CAPTURECOUNT
</pre>
Return the number of capturing subpatterns in the pattern. The third argument
should point to an <b>uint32_t</b> variable.
Return the highest capturing subpattern number in the pattern. In patterns
where (?| is not used, this is also the total number of capturing subpatterns.
The third argument should point to an <b>uint32_t</b> variable.
<pre>
PCRE2_INFO_FIRSTBITMAP
</pre>
In the absence of a single first code unit for a non-anchored pattern,
<b>pcre2_compile()</b> may construct a 256-bit table that defines a fixed set of
values for the first code unit in any match. For example, a pattern that starts
with [abc] results in a table with three bits set. When code unit values
greater than 255 are supported, the flag bit for 255 means "any code unit of
value 255 or above". If such a table was constructed, a pointer to it is
returned. Otherwise NULL is returned. The third argument should point to an
<b>const uint8_t *</b> variable.
<pre>
PCRE2_INFO_FIRSTCODETYPE
</pre>
Return information about the first code unit of any matched string, for a
non-anchored pattern. The third argument should point to an <b>uint32_t</b>
variable.
</P>
<P>
If there is a fixed first value, for example, the letter "c" from a pattern
such as (cat|cow|coyote), 1 is returned, and the character value can be
variable. If there is a fixed first value, for example, the letter "c" from a
pattern such as (cat|cow|coyote), 1 is returned, and the character value can be
retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no fixed first value, but
it is known that a match can occur only at the start of the subject or
following a newline in the subject, 2 is returned. Otherwise, and for anchored
@ -1635,16 +1647,10 @@ value is always less than 256. In the 16-bit library the value can be up to
0xffff. In the 32-bit library in UTF-32 mode the value can be up to 0x10ffff,
and up to 0xffffffff when not using UTF-32 mode.
<pre>
PCRE2_INFO_FIRSTBITMAP
PCRE2_INFO_HASBACKSLASHC
</pre>
In the absence of a single first code unit for a non-anchored pattern,
<b>pcre2_compile()</b> may construct a 256-bit table that defines a fixed set of
values for the first code unit in any match. For example, a pattern that starts
with [abc] results in a table with three bits set. When code unit values
greater than 255 are supported, the flag bit for 255 means "any code unit of
value 255 or above". If such a table was constructed, a pointer to it is
returned. Otherwise NULL is returned. The third argument should point to an
<b>const uint8_t *</b> variable.
Return 1 if the pattern contains any instances of \C, otherwise 0. The third
argument should point to an <b>uint32_t</b> variable.
<pre>
PCRE2_INFO_HASCRORLF
</pre>
@ -1670,13 +1676,10 @@ Returns 1 if there is a rightmost literal code unit that must exist in any
matched string, other than at its start. The third argument should point to an
<b>uint32_t</b> variable. If there is no such value, 0 is returned. When 1 is
returned, the code unit value itself can be retrieved using
PCRE2_INFO_LASTCODEUNIT.
</P>
<P>
For anchored patterns, a last literal value is recorded only if it follows
something of variable length. For example, for the pattern /^a\d+z\d+/ the
returned value is 1 (with "z" returned from PCRE2_INFO_LASTCODEUNIT), but for
/^a\dz\d/ the returned value is 0.
PCRE2_INFO_LASTCODEUNIT. For anchored patterns, a last literal value is
recorded only if it follows something of variable length. For example, for the
pattern /^a\d+z\d+/ the returned value is 1 (with "z" returned from
PCRE2_INFO_LASTCODEUNIT), but for /^a\dz\d/ the returned value is 0.
<pre>
PCRE2_INFO_LASTCODEUNIT
</pre>
@ -1687,8 +1690,11 @@ value, 0 is returned.
<pre>
PCRE2_INFO_MATCHEMPTY
</pre>
Return 1 if the pattern can match an empty string, otherwise 0. The third
argument should point to an <b>uint32_t</b> variable.
Return 1 if the pattern might match an empty string, otherwise 0. The third
argument should point to an <b>uint32_t</b> variable. When a pattern contains
recursive subroutine calls it is not always possible to determine whether or
not it can match an empty string. PCRE2 takes a cautious approach and returns 1
in such cases.
<pre>
PCRE2_INFO_MATCHLIMIT
</pre>
@ -2142,8 +2148,13 @@ documentation.
When PCRE2 is built, a default newline convention is set; this is usually the
standard convention for the operating system. The default can be overridden in
a
<a href="#compilecontext">compile context.</a>
During matching, the newline choice affects the behaviour of the dot,
<a href="#compilecontext">compile context</a>
by calling <b>pcre2_set_newline()</b>. It can also be overridden by starting a
pattern string with, for example, (*CRLF), as described in the
<a href="pcre2pattern.html#newlines">section on newline conventions</a>
in the
<a href="pcre2pattern.html"><b>pcre2pattern</b></a>
page. During matching, the newline choice affects the behaviour of the dot,
circumflex, and dollar metacharacters. It may also alter the way the match
starting position is advanced after a match failure for an unanchored pattern.
</P>
@ -2191,19 +2202,20 @@ function can be used to find out how many capturing subpatterns there are in a
compiled pattern.
</P>
<P>
A successful match returns the overall matched string and any captured
substrings to the caller via a vector of PCRE2_SIZE values. This is called the
<b>ovector</b>, and is contained within the
<a href="#matchdatablock">match data block.</a>
You can obtain direct access to the ovector by calling
<b>pcre2_get_ovector_pointer()</b> to find its address, and
<b>pcre2_get_ovector_count()</b> to find the number of pairs of values it
contains. Alternatively, you can use the auxiliary functions for accessing
captured substrings
You can use auxiliary functions for accessing captured substrings
<a href="#extractbynumber">by number</a>
or
<a href="#extractbyname">by name</a>
(see below).
<a href="#extractbyname">by name,</a>
as described in sections below.
</P>
<P>
Alternatively, you can make direct use of the vector of PCRE2_SIZE values,
called the <b>ovector</b>, which contains the offsets of captured strings. It is
part of the
<a href="#matchdatablock">match data block.</a>
The function <b>pcre2_get_ovector_pointer()</b> returns the address of the
ovector, and <b>pcre2_get_ovector_count()</b> returns the number of pairs of
values it contains.
</P>
<P>
Within the ovector, the first in each pair of values is set to the offset of
@ -2292,7 +2304,13 @@ After a successful match, a partial match (PCRE2_ERROR_PARTIAL), or a failure
to match (PCRE2_ERROR_NOMATCH), a (*MARK) name may be available, and
<b>pcre2_get_mark()</b> can be called. It returns a pointer to the
zero-terminated name, which is within the compiled pattern. Otherwise NULL is
returned. After a successful match, the (*MARK) name that is returned is the
returned. The length of the (*MARK) name (excluding the terminating zero) is
stored in the code unit that preceeds the name. You should use this instead of
relying on the terminating zero if the (*MARK) name might contain a binary
zero.
</P>
<P>
After a successful match, the (*MARK) name that is returned is the
last one encountered on the matching path through the pattern. After a "no
match" or a partial match, the last encountered (*MARK) name is returned. For
example, consider this pattern:
@ -2313,7 +2331,7 @@ escape sequence. After a partial match, however, this value is always the same
as <i>ovector[0]</i> because \K does not affect the result of a partial match.
</P>
<P>
After a UTF check failure, \fBpcre2_get_startchar()\fB can be used to obtain
After a UTF check failure, <b>pcre2_get_startchar()</b> can be used to obtain
the code unit offset of the invalid UTF character. Details are given in the
<a href="pcre2unicode.html"><b>pcre2unicode</b></a>
page.
@ -2650,12 +2668,21 @@ allocate memory for the compiled code.
</P>
<P>
The <i>outlengthptr</i> argument must point to a variable that contains the
length, in code units, of the output buffer. If the function is successful,
the value is updated to contain the length of the new string, excluding the
trailing zero that is automatically added. If the function is not successful,
the value is set to PCRE2_UNSET for general errors (such as output buffer too
small). For syntax errors in the replacement string, the value is set to the
offset in the replacement string where the error was detected.
length, in code units, of the output buffer. If the function is successful, the
value is updated to contain the length of the new string, excluding the
trailing zero that is automatically added.
</P>
<P>
If the function is not successful, the value set via <i>outlengthptr</i> depends
on the type of error. For syntax errors in the replacement string, the value is
the offset in the replacement string where the error was detected. For other
errors, the value is PCRE2_UNSET by default. This includes the case of the
output buffer being too small, unless PCRE2_SUBSTITUTE_OVERFLOW_LENGTH is set
(see below), in which case the value is the minimum length needed, including
space for the trailing zero. Note that in order to compute the required length,
<b>pcre2_substitute()</b> has to simulate all the matching and copying, instead
of giving an error return as soon as the buffer overflows. Note also that the
length is in code units, not bytes.
</P>
<P>
In the replacement string, which is interpreted as a UTF string in UTF mode,
@ -2682,15 +2709,53 @@ simultaneous substitutions, as this <b>pcre2test</b> example shows:
apple lemon
2: pear orange
</pre>
There is an additional option, PCRE2_SUBSTITUTE_GLOBAL, which causes the
function to iterate over the subject string, replacing every matching
substring. If this is not set, only the first matching substring is replaced.
As well as the usual options for <b>pcre2_match()</b>, a number of additional
options can be set in the <i>options</i> argument.
</P>
<P>
A second additional option, PCRE2_SUBSTITUTE_EXTENDED, causes extra processing
to be applied to the replacement string. Without this option, only the dollar
character is special, and only the group insertion forms listed above are
valid. When PCRE2_SUBSTITUTE_EXTENDED is set, two things change:
PCRE2_SUBSTITUTE_GLOBAL causes the function to iterate over the subject string,
replacing every matching substring. If this is not set, only the first matching
substring is replaced. If any matched substring has zero length, after the
substitution has happened, an attempt to find a non-empty match at the same
position is performed. If this is not successful, the current position is
advanced by one character except when CRLF is a valid newline sequence and the
next two characters are CR, LF. In this case, the current position is advanced
by two characters.
</P>
<P>
PCRE2_SUBSTITUTE_OVERFLOW_LENGTH changes what happens when the output buffer is
too small. The default action is to return PCRE2_ERROR_NOMEMORY immediately. If
this option is set, however, <b>pcre2_substitute()</b> continues to go through
the motions of matching and substituting (without, of course, writing anything)
in order to compute the size of buffer that is needed. This value is passed
back via the <i>outlengthptr</i> variable, with the result of the function still
being PCRE2_ERROR_NOMEMORY.
</P>
<P>
Passing a buffer size of zero is a permitted way of finding out how much memory
is needed for given substitution. However, this does mean that the entire
operation is carried out twice. Depending on the application, it may be more
efficient to allocate a large buffer and free the excess afterwards, instead of
using PCRE2_SUBSTITUTE_OVERFLOW_LENGTH.
</P>
<P>
PCRE2_SUBSTITUTE_UNKNOWN_UNSET causes references to capturing groups that do
not appear in the pattern to be treated as unset groups. This option should be
used with care, because it means that a typo in a group name or number no
longer causes the PCRE2_ERROR_NOSUBSTRING error.
</P>
<P>
PCRE2_SUBSTITUTE_UNSET_EMPTY causes unset capturing groups (including unknown
groups when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) to be treated as empty
strings when inserted as described above. If this option is not set, an attempt
to insert an unset group causes the PCRE2_ERROR_UNSET error. This option does
not influence the extended substitution syntax described below.
</P>
<P>
PCRE2_SUBSTITUTE_EXTENDED causes extra processing to be applied to the
replacement string. Without this option, only the dollar character is special,
and only the group insertion forms listed above are valid. When
PCRE2_SUBSTITUTE_EXTENDED is set, two things change:
</P>
<P>
Firstly, backslash in a replacement string is interpreted as an escape
@ -2740,22 +2805,46 @@ string remains in force afterwards, as shown in this <b>pcre2test</b> example:
somebody
1: HELLO
</pre>
If successful, the function returns the number of replacements that were made.
This may be zero if no matches were found, and is never greater than 1 unless
PCRE2_SUBSTITUTE_GLOBAL is set.
The PCRE2_SUBSTITUTE_UNSET_EMPTY option does not affect these extended
substitutions. However, PCRE2_SUBSTITUTE_UNKNOWN_UNSET does cause unknown
groups in the extended syntax forms to be treated as unset.
</P>
<P>
If successful, <b>pcre2_substitute()</b> returns the number of replacements that
were made. This may be zero if no matches were found, and is never greater than
1 unless PCRE2_SUBSTITUTE_GLOBAL is set.
</P>
<P>
In the event of an error, a negative error code is returned. Except for
PCRE2_ERROR_NOMATCH (which is never returned), errors from <b>pcre2_match()</b>
are passed straight back. PCRE2_ERROR_NOMEMORY is returned if the output buffer
is not big enough. PCRE2_ERROR_BADREPLACEMENT is used for miscellaneous syntax
errors in the replacement string, with more particular errors being
PCRE2_ERROR_BADREPESCAPE (invalid escape sequence),
PCRE2_ERROR_REPMISSING_BRACE (closing curly bracket not found),
PCRE2_BADSUBSTITUTION (syntax error in extended group substitution), and
PCRE2_BADSUBPATTERN (the pattern match ended before it started). As for all
PCRE2 errors, a text message that describes the error can be obtained by
calling <b>pcre2_get_error_message()</b>.
are passed straight back.
</P>
<P>
PCRE2_ERROR_NOSUBSTRING is returned for a non-existent substring insertion,
unless PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set.
</P>
<P>
PCRE2_ERROR_UNSET is returned for an unset substring insertion (including an
unknown substring when PCRE2_SUBSTITUTE_UNKNOWN_UNSET is set) when the simple
(non-extended) syntax is used and PCRE2_SUBSTITUTE_UNSET_EMPTY is not set.
</P>
<P>
PCRE2_ERROR_NOMEMORY is returned if the output buffer is not big enough. If the
PCRE2_SUBSTITUTE_OVERFLOW_LENGTH option is set, the size of buffer that is
needed is returned via <i>outlengthptr</i>. Note that this does not happen by
default.
</P>
<P>
PCRE2_ERROR_BADREPLACEMENT is used for miscellaneous syntax errors in the
replacement string, with more particular errors being PCRE2_ERROR_BADREPESCAPE
(invalid escape sequence), PCRE2_ERROR_REPMISSING_BRACE (closing curly bracket
not found), PCRE2_BADSUBSTITUTION (syntax error in extended group
substitution), and PCRE2_BADSUBPATTERN (the pattern match ended before it
started, which can happen if \K is used in an assertion).
</P>
<P>
As for all PCRE2 errors, a text message that describes the error can be
obtained by calling <b>pcre2_get_error_message()</b>.
</P>
<br><a name="SEC35" href="#TOC1">DUPLICATE SUBPATTERN NAMES</a><br>
<P>
@ -2796,11 +2885,11 @@ function returns the length of each entry in code units. In both cases,
PCRE2_ERROR_NOSUBSTRING is returned if there are no entries for the given name.
</P>
<P>
The format of the name table is described above in the section entitled
<i>Information about a pattern</i>
<a href="#infoaboutpattern">above.</a>
Given all the relevant entries for the name, you can extract each of their
numbers, and hence the captured data.
The format of the name table is described
<a href="#infoaboutpattern">above</a>
in the section entitled <i>Information about a pattern</i>. Given all the
relevant entries for the name, you can extract each of their numbers, and hence
the captured data.
</P>
<br><a name="SEC36" href="#TOC1">FINDING ALL POSSIBLE MATCHES AT ONE POSITION</a><br>
<P>
@ -3032,7 +3121,7 @@ Cambridge, England.
</P>
<br><a name="SEC40" href="#TOC1">REVISION</a><br>
<P>
Last updated: 05 November 2015
Last updated: 16 December 2015
<br>
Copyright &copy; 1997-2015 University of Cambridge.
<br>

View File

@ -86,6 +86,13 @@ results. The returned value from <b>pcre2_jit_compile()</b> is zero on success,
or a negative error code.
</P>
<P>
There is a limit to the size of pattern that JIT supports, imposed by the size
of machine stack that it uses. The exact rules are not documented because they
may change at any time, in particular, when new optimizations are introduced.
If a pattern is too big, a call to \fBpcre2_jit_compile()\fB returns
PCRE2_ERROR_NOMEMORY.
</P>
<P>
PCRE2_JIT_COMPLETE requests the JIT compiler to generate code for complete
matches. If you want to run partial matches using the PCRE2_PARTIAL_HARD or
PCRE2_PARTIAL_SOFT options of <b>pcre2_match()</b>, you should set one or both
@ -425,7 +432,7 @@ Cambridge, England.
</P>
<br><a name="SEC13" href="#TOC1">REVISION</a><br>
<P>
Last updated: 28 July 2015
Last updated: 14 November 2015
<br>
Copyright &copy; 1997-2015 University of Cambridge.
<br>

View File

@ -669,8 +669,8 @@ This is an example of an "atomic group", details of which are given
This particular group matches either the two-character sequence CR followed by
LF, or one of the single characters LF (linefeed, U+000A), VT (vertical tab,
U+000B), FF (form feed, U+000C), CR (carriage return, U+000D), or NEL (next
line, U+0085). The two-character sequence is treated as a single unit that
cannot be split.
line, U+0085). Because this is an atomic group, the two-character sequence is
treated as a single unit that cannot be split.
</P>
<P>
In other modes, two additional characters whose codepoints are greater than 255
@ -1186,6 +1186,16 @@ when the <i>startoffset</i> argument of <b>pcre2_match()</b> is non-zero. The
PCRE2_DOLLAR_ENDONLY option is ignored if PCRE2_MULTILINE is set.
</P>
<P>
When the newline convention (see
<a href="#newlines">"Newline conventions"</a>
below) recognizes the two-character sequence CRLF as a newline, this is
preferred, even if the single characters CR and LF are also recognized as
newlines. For example, if the newline convention is "any", a multiline mode
circumflex matches before "xyz" in the string "abc\r\nxyz" rather than after
CR, even though CR on its own is a valid newline. (It also matches at the very
start of the string, of course.)
</P>
<P>
Note that the sequences \A, \Z, and \z can be used to match the start and
end of the subject in both modes, and if all branches of a pattern start with
\A it is always anchored, whether or not PCRE2_MULTILINE is set.
@ -1672,6 +1682,10 @@ first one in the pattern with the given number. The following pattern matches
<pre>
/(?|(abc)|(def))(?1)/
</pre>
A relative reference such as (?-1) is no different: it is just a convenient way
of computing an absolute group number.
</P>
<P>
If a
<a href="#conditions">condition test</a>
for a subpattern's having matched refers to a non-unique number, the test is
@ -2626,6 +2640,21 @@ parentheses preceding the recursion. In other words, a negative number counts
capturing parentheses leftwards from the point at which it is encountered.
</P>
<P>
Be aware however, that if
<a href="#dupsubpatternnumber">duplicate subpattern numbers</a>
are in use, relative references refer to the earliest subpattern with the
appropriate number. Consider, for example:
<pre>
(?|(a)|(b)) (c) (?-2)
</pre>
The first two capturing groups (a) and (b) are both numbered 1, and group (c)
is number 2. When the reference (?-2) is encountered, the second most recently
opened parentheses has the number 1, but it is the first such group (the (a)
group) to which the recursion refers. This would be the same if an absolute
reference (?1) was used. In other words, relative references are just a
shorthand for computing a group number.
</P>
<P>
It is also possible to refer to subsequently opened parentheses, by writing
references such as (?+2). However, these cannot be recursive because the
reference is not inside the parentheses that are referenced. They are always
@ -3359,7 +3388,7 @@ Cambridge, England.
</P>
<br><a name="SEC30" href="#TOC1">REVISION</a><br>
<P>
Last updated: 01 November 2015
Last updated: 13 November 2015
<br>
Copyright &copy; 1997-2015 University of Cambridge.
<br>

View File

@ -235,7 +235,8 @@ to have a terminating NUL located at <i>string</i> + <i>pmatch[0].rm_eo</i>
IEEE Standard 1003.2 (POSIX.2), and should be used with caution in software
intended to be portable to other systems. Note that a non-zero <i>rm_so</i> does
not imply REG_NOTBOL; REG_STARTEND affects only the location of the string, not
how it is matched.
how it is matched. Setting REG_STARTEND and passing <i>pmatch</i> as NULL are
mutually exclusive; the error REG_INVARG is returned.
</P>
<P>
If the pattern was compiled with the REG_NOSUB flag, no data about any matched
@ -289,7 +290,7 @@ Cambridge, England.
</P>
<br><a name="SEC9" href="#TOC1">REVISION</a><br>
<P>
Last updated: 30 October 2015
Last updated: 29 November 2015
<br>
Copyright &copy; 1997-2015 University of Cambridge.
<br>

View File

@ -892,14 +892,18 @@ are applied to every subject line that is processed with that pattern. They may
not appear in <b>#pattern</b> commands. These modifiers do not affect the
compilation process.
<pre>
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text
/g global global matching
mark show mark values
replace=&#60;string&#62; specify a replacement string
startchar show starting character when relevant
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text
/g global global matching
mark show mark values
replace=&#60;string&#62; specify a replacement string
startchar show starting character when relevant
substitute_extended use PCRE2_SUBSTITUTE_EXTENDED
substitute_overflow_length use PCRE2_SUBSTITUTE_OVERFLOW_LENGTH
substitute_unknown_unset use PCRE2_SUBSTITUTE_UNKNOWN_UNSET
substitute_unset_empty use PCRE2_SUBSTITUTE_UNSET_EMPTY
</pre>
These modifiers may not appear in a <b>#pattern</b> command. If you want them as
defaults, set them in a <b>#subject</b> command.
@ -964,33 +968,38 @@ information. Some of them may also be specified on a pattern line (see above),
in which case they apply to every subject line that is matched against that
pattern.
<pre>
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text (non-JIT only)
altglobal alternative global matching
callout_capture show captures at callout time
callout_data=&#60;n&#62; set a value to pass via callouts
callout_fail=&#60;n&#62;[:&#60;m&#62;] control callout failure
callout_none do not supply a callout function
copy=&#60;number or name&#62; copy captured substring
dfa use <b>pcre2_dfa_match()</b>
find_limits find match and recursion limits
get=&#60;number or name&#62; extract captured substring
getall extract all captured substrings
/g global global matching
jitstack=&#60;n&#62; set size of JIT stack
mark show mark values
match_limit=&#60;n&#62; set a match limit
memory show memory usage
null_context match with a NULL context
offset=&#60;n&#62; set starting offset
offset_limit=&#60;n&#62; set offset limit
ovector=&#60;n&#62; set size of output vector
recursion_limit=&#60;n&#62; set a recursion limit
replace=&#60;string&#62; specify a replacement string
startchar show startchar when relevant
zero_terminate pass the subject as zero-terminated
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text (non-JIT only)
altglobal alternative global matching
callout_capture show captures at callout time
callout_data=&#60;n&#62; set a value to pass via callouts
callout_fail=&#60;n&#62;[:&#60;m&#62;] control callout failure
callout_none do not supply a callout function
copy=&#60;number or name&#62; copy captured substring
dfa use <b>pcre2_dfa_match()</b>
find_limits find match and recursion limits
get=&#60;number or name&#62; extract captured substring
getall extract all captured substrings
/g global global matching
jitstack=&#60;n&#62; set size of JIT stack
mark show mark values
match_limit=&#60;n&#62; set a match limit
memory show memory usage
null_context match with a NULL context
offset=&#60;n&#62; set starting offset
offset_limit=&#60;n&#62; set offset limit
ovector=&#60;n&#62; set size of output vector
recursion_limit=&#60;n&#62; set a recursion limit
replace=&#60;string&#62; specify a replacement string
startchar show startchar when relevant
startoffset=&#60;n&#62; same as offset=&#60;n&#62;
substitute_extedded use PCRE2_SUBSTITUTE_EXTENDED
substitute_overflow_length use PCRE2_SUBSTITUTE_OVERFLOW_LENGTH
substitute_unknown_unset use PCRE2_SUBSTITUTE_UNKNOWN_UNSET
substitute_unset_empty use PCRE2_SUBSTITUTE_UNSET_EMPTY
zero_terminate pass the subject as zero-terminated
</pre>
The effects of these modifiers are described in the following sections.
</P>
@ -1129,19 +1138,34 @@ Testing the substitution function
</b><br>
<P>
If the <b>replace</b> modifier is set, the <b>pcre2_substitute()</b> function is
called instead of one of the matching functions. Unlike subject strings,
<b>pcre2test</b> does not process replacement strings for escape sequences. In
UTF mode, a replacement string is checked to see if it is a valid UTF-8 string.
If so, it is correctly converted to a UTF string of the appropriate code unit
width. If it is not a valid UTF-8 string, the individual code units are copied
directly. This provides a means of passing an invalid UTF-8 string for testing
purposes.
called instead of one of the matching functions. Note that replacement strings
cannot contain commas, because a comma signifies the end of a modifier. This is
not thought to be an issue in a test program.
</P>
<P>
If the <b>global</b> modifier is set, PCRE2_SUBSTITUTE_GLOBAL is passed to
<b>pcre2_substitute()</b>. After a successful substitution, the modified string
is output, preceded by the number of replacements. This may be zero if there
were no matches. Here is a simple example of a substitution test:
Unlike subject strings, <b>pcre2test</b> does not process replacement strings
for escape sequences. In UTF mode, a replacement string is checked to see if it
is a valid UTF-8 string. If so, it is correctly converted to a UTF string of
the appropriate code unit width. If it is not a valid UTF-8 string, the
individual code units are copied directly. This provides a means of passing an
invalid UTF-8 string for testing purposes.
</P>
<P>
The following modifiers set options (in additional to the normal match options)
for <b>pcre2_substitute()</b>:
<pre>
global PCRE2_SUBSTITUTE_GLOBAL
substitute_extended PCRE2_SUBSTITUTE_EXTENDED
substitute_overflow_length PCRE2_SUBSTITUTE_OVERFLOW_LENGTH
substitute_unknown_unset PCRE2_SUBSTITUTE_UNKNOWN_UNSET
substitute_unset_empty PCRE2_SUBSTITUTE_UNSET_EMPTY
</PRE>
</P>
<P>
After a successful substitution, the modified string is output, preceded by the
number of replacements. This may be zero if there were no matches. Here is a
simple example of a substitution test:
<pre>
/abc/replace=xxx
=abc=abc=
@ -1149,12 +1173,12 @@ were no matches. Here is a simple example of a substitution test:
=abc=abc=\=global
2: =xxx=xxx=
</pre>
Subject and replacement strings should be kept relatively short for
substitution tests, as fixed-size buffers are used. To make it easy to test for
buffer overflow, if the replacement string starts with a number in square
brackets, that number is passed to <b>pcre2_substitute()</b> as the size of the
output buffer, with the replacement string starting at the next character. Here
is an example that tests the edge case:
Subject and replacement strings should be kept relatively short (fewer than 256
characters) for substitution tests, as fixed-size buffers are used. To make it
easy to test for buffer overflow, if the replacement string starts with a
number in square brackets, that number is passed to <b>pcre2_substitute()</b> as
the size of the output buffer, with the replacement string starting at the next
character. Here is an example that tests the edge case:
<pre>
/abc/
123abc123\=replace=[10]XYZ
@ -1162,6 +1186,19 @@ is an example that tests the edge case:
123abc123\=replace=[9]XYZ
Failed: error -47: no more memory
</pre>
The default action of <b>pcre2_substitute()</b> is to return
PCRE2_ERROR_NOMEMORY when the output buffer is too small. However, if the
PCRE2_SUBSTITUTE_OVERFLOW_LENGTH option is set (by using the
<b>substitute_overflow_length</b> modifier), <b>pcre2_substitute()</b> continues
to go through the motions of matching and substituting, in order to compute the
size of buffer that is required. When this happens, <b>pcre2test</b> shows the
required buffer length (which includes space for the trailing zero) as part of
the error message. For example:
<pre>
/abc/substitute_overflow_length
123abc123\=replace=[9]XYZ
Failed: error -47: no more memory: 10 code units are needed
</pre>
A replacement string is ignored with POSIX and DFA matching. Specifying partial
matching provokes an error return ("bad option value") from
<b>pcre2_substitute()</b>.
@ -1623,7 +1660,7 @@ Cambridge, England.
</P>
<br><a name="SEC21" href="#TOC1">REVISION</a><br>
<P>
Last updated: 05 November 2015
Last updated: 12 December 2015
<br>
Copyright &copy; 1997-2015 University of Cambridge.
<br>

File diff suppressed because it is too large Load Diff

View File

@ -1,4 +1,4 @@
.TH PCRE2API 3 "12 December 2015" "PCRE2 10.21"
.TH PCRE2API 3 "16 December 2015" "PCRE2 10.21"
.SH NAME
PCRE2 - Perl-compatible regular expressions (revised API)
.sp
@ -678,8 +678,8 @@ of the following match-time parameters:
.sp
A callout function
The offset limit for matching an unanchored pattern
The limit for calling \fImatch()\fP
The limit for calling \fImatch()\fP recursively
The limit for calling \fBmatch()\fP (see below)
The limit for calling \fBmatch()\fP recursively
.sp
A match context is also required if you are using custom memory management.
If none of these apply, just pass NULL as the context argument of
@ -1611,8 +1611,9 @@ matches only CR, LF, or CRLF.
.sp
PCRE2_INFO_CAPTURECOUNT
.sp
Return the number of capturing subpatterns in the pattern. The third argument
should point to an \fBuint32_t\fP variable.
Return the highest capturing subpattern number in the pattern. In patterns
where (?| is not used, this is also the total number of capturing subpatterns.
The third argument should point to an \fBuint32_t\fP variable.
.sp
PCRE2_INFO_FIRSTBITMAP
.sp
@ -1629,10 +1630,8 @@ returned. Otherwise NULL is returned. The third argument should point to an
.sp
Return information about the first code unit of any matched string, for a
non-anchored pattern. The third argument should point to an \fBuint32_t\fP
variable.
.P
If there is a fixed first value, for example, the letter "c" from a pattern
such as (cat|cow|coyote), 1 is returned, and the character value can be
variable. If there is a fixed first value, for example, the letter "c" from a
pattern such as (cat|cow|coyote), 1 is returned, and the character value can be
retrieved using PCRE2_INFO_FIRSTCODEUNIT. If there is no fixed first value, but
it is known that a match can occur only at the start of the subject or
following a newline in the subject, 2 is returned. Otherwise, and for anchored
@ -1676,12 +1675,10 @@ Returns 1 if there is a rightmost literal code unit that must exist in any
matched string, other than at its start. The third argument should point to an
\fBuint32_t\fP variable. If there is no such value, 0 is returned. When 1 is
returned, the code unit value itself can be retrieved using
PCRE2_INFO_LASTCODEUNIT.
.P
For anchored patterns, a last literal value is recorded only if it follows
something of variable length. For example, for the pattern /^a\ed+z\ed+/ the
returned value is 1 (with "z" returned from PCRE2_INFO_LASTCODEUNIT), but for
/^a\edz\ed/ the returned value is 0.
PCRE2_INFO_LASTCODEUNIT. For anchored patterns, a last literal value is
recorded only if it follows something of variable length. For example, for the
pattern /^a\ed+z\ed+/ the returned value is 1 (with "z" returned from
PCRE2_INFO_LASTCODEUNIT), but for /^a\edz\ed/ the returned value is 0.
.sp
PCRE2_INFO_LASTCODEUNIT
.sp
@ -2181,9 +2178,19 @@ standard convention for the operating system. The default can be overridden in
a
.\" HTML <a href="#compilecontext">
.\" </a>
compile context.
compile context
.\"
During matching, the newline choice affects the behaviour of the dot,
by calling \fBpcre2_set_newline()\fP. It can also be overridden by starting a
pattern string with, for example, (*CRLF), as described in the
.\" HTML <a href="pcre2pattern.html#newlines">
.\" </a>
section on newline conventions
.\"
in the
.\" HREF
\fBpcre2pattern\fP
.\"
page. During matching, the newline choice affects the behaviour of the dot,
circumflex, and dollar metacharacters. It may also alter the way the match
starting position is advanced after a match failure for an unanchored pattern.
.P
@ -2229,18 +2236,7 @@ that do not cause substrings to be captured. The \fBpcre2_pattern_info()\fP
function can be used to find out how many capturing subpatterns there are in a
compiled pattern.
.P
A successful match returns the overall matched string and any captured
substrings to the caller via a vector of PCRE2_SIZE values. This is called the
\fBovector\fP, and is contained within the
.\" HTML <a href="#matchdatablock">
.\" </a>
match data block.
.\"
You can obtain direct access to the ovector by calling
\fBpcre2_get_ovector_pointer()\fP to find its address, and
\fBpcre2_get_ovector_count()\fP to find the number of pairs of values it
contains. Alternatively, you can use the auxiliary functions for accessing
captured substrings
You can use auxiliary functions for accessing captured substrings
.\" HTML <a href="#extractbynumber">
.\" </a>
by number
@ -2248,9 +2244,20 @@ by number
or
.\" HTML <a href="#extractbyname">
.\" </a>
by name
by name,
.\"
(see below).
as described in sections below.
.P
Alternatively, you can make direct use of the vector of PCRE2_SIZE values,
called the \fBovector\fP, which contains the offsets of captured strings. It is
part of the
.\" HTML <a href="#matchdatablock">
.\" </a>
match data block.
.\"
The function \fBpcre2_get_ovector_pointer()\fP returns the address of the
ovector, and \fBpcre2_get_ovector_count()\fP returns the number of pairs of
values it contains.
.P
Within the ovector, the first in each pair of values is set to the offset of
the first code unit of a substring, and the second is set to the offset of the
@ -2334,7 +2341,12 @@ After a successful match, a partial match (PCRE2_ERROR_PARTIAL), or a failure
to match (PCRE2_ERROR_NOMATCH), a (*MARK) name may be available, and
\fBpcre2_get_mark()\fP can be called. It returns a pointer to the
zero-terminated name, which is within the compiled pattern. Otherwise NULL is
returned. After a successful match, the (*MARK) name that is returned is the
returned. The length of the (*MARK) name (excluding the terminating zero) is
stored in the code unit that preceeds the name. You should use this instead of
relying on the terminating zero if the (*MARK) name might contain a binary
zero.
.P
After a successful match, the (*MARK) name that is returned is the
last one encountered on the matching path through the pattern. After a "no
match" or a partial match, the last encountered (*MARK) name is returned. For
example, consider this pattern:
@ -2353,7 +2365,7 @@ different to the value of \fIovector[0]\fP if the pattern contains the \eK
escape sequence. After a partial match, however, this value is always the same
as \fIovector[0]\fP because \eK does not affect the result of a partial match.
.P
After a UTF check failure, \fBpcre2_get_startchar()\fB can be used to obtain
After a UTF check failure, \fBpcre2_get_startchar()\fP can be used to obtain
the code unit offset of the invalid UTF character. Details are given in the
.\" HREF
\fBpcre2unicode\fP
@ -2901,14 +2913,14 @@ first and last entries in the name-to-number table for the given name, and the
function returns the length of each entry in code units. In both cases,
PCRE2_ERROR_NOSUBSTRING is returned if there are no entries for the given name.
.P
The format of the name table is described above in the section entitled
\fIInformation about a pattern\fP
The format of the name table is described
.\" HTML <a href="#infoaboutpattern">
.\" </a>
above.
above
.\"
Given all the relevant entries for the name, you can extract each of their
numbers, and hence the captured data.
in the section entitled \fIInformation about a pattern\fP. Given all the
relevant entries for the name, you can extract each of their numbers, and hence
the captured data.
.
.
.SH "FINDING ALL POSSIBLE MATCHES AT ONE POSITION"
@ -3154,6 +3166,6 @@ Cambridge, England.
.rs
.sp
.nf
Last updated: 21 December 2015
Last updated: 16 December 2015
Copyright (c) 1997-2015 University of Cambridge.
.fi

View File

@ -797,14 +797,18 @@ PATTERN MODIFIERS
with that pattern. They may not appear in #pattern commands. These mod-
ifiers do not affect the compilation process.
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text
/g global global matching
mark show mark values
replace=<string> specify a replacement string
startchar show starting character when relevant
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text
/g global global matching
mark show mark values
replace=<string> specify a replacement string
startchar show starting character when relevant
substitute_extended use PCRE2_SUBSTITUTE_EXTENDED
substitute_overflow_length use PCRE2_SUBSTITUTE_OVERFLOW_LENGTH
substitute_unknown_unset use PCRE2_SUBSTITUTE_UNKNOWN_UNSET
substitute_unset_empty use PCRE2_SUBSTITUTE_UNSET_EMPTY
These modifiers may not appear in a #pattern command. If you want them
as defaults, set them in a #subject command.
@ -860,33 +864,38 @@ SUBJECT MODIFIERS
line (see above), in which case they apply to every subject line that
is matched against that pattern.
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text (non-JIT only)
altglobal alternative global matching
callout_capture show captures at callout time
callout_data=<n> set a value to pass via callouts
callout_fail=<n>[:<m>] control callout failure
callout_none do not supply a callout function
copy=<number or name> copy captured substring
dfa use pcre2_dfa_match()
find_limits find match and recursion limits
get=<number or name> extract captured substring
getall extract all captured substrings
/g global global matching
jitstack=<n> set size of JIT stack
mark show mark values
match_limit=<n> set a match limit
memory show memory usage
null_context match with a NULL context
offset=<n> set starting offset
offset_limit=<n> set offset limit
ovector=<n> set size of output vector
recursion_limit=<n> set a recursion limit
replace=<string> specify a replacement string
startchar show startchar when relevant
zero_terminate pass the subject as zero-terminated
aftertext show text after match
allaftertext show text after captures
allcaptures show all captures
allusedtext show all consulted text (non-JIT only)
altglobal alternative global matching
callout_capture show captures at callout time
callout_data=<n> set a value to pass via callouts
callout_fail=<n>[:<m>] control callout failure
callout_none do not supply a callout function
copy=<number or name> copy captured substring
dfa use pcre2_dfa_match()
find_limits find match and recursion limits
get=<number or name> extract captured substring
getall extract all captured substrings
/g global global matching
jitstack=<n> set size of JIT stack
mark show mark values
match_limit=<n> set a match limit
memory show memory usage
null_context match with a NULL context
offset=<n> set starting offset
offset_limit=<n> set offset limit
ovector=<n> set size of output vector
recursion_limit=<n> set a recursion limit
replace=<string> specify a replacement string
startchar show startchar when relevant
startoffset=<n> same as offset=<n>
substitute_extedded use PCRE2_SUBSTITUTE_EXTENDED
substitute_overflow_length use PCRE2_SUBSTITUTE_OVERFLOW_LENGTH
substitute_unknown_unset use PCRE2_SUBSTITUTE_UNKNOWN_UNSET
substitute_unset_empty use PCRE2_SUBSTITUTE_UNSET_EMPTY
zero_terminate pass the subject as zero-terminated
The effects of these modifiers are described in the following sections.
@ -1011,19 +1020,30 @@ SUBJECT MODIFIERS
Testing the substitution function
If the replace modifier is set, the pcre2_substitute() function is
called instead of one of the matching functions. Unlike subject
strings, pcre2test does not process replacement strings for escape
sequences. In UTF mode, a replacement string is checked to see if it is
a valid UTF-8 string. If so, it is correctly converted to a UTF string
of the appropriate code unit width. If it is not a valid UTF-8 string,
the individual code units are copied directly. This provides a means of
passing an invalid UTF-8 string for testing purposes.
called instead of one of the matching functions. Note that replacement
strings cannot contain commas, because a comma signifies the end of a
modifier. This is not thought to be an issue in a test program.
If the global modifier is set, PCRE2_SUBSTITUTE_GLOBAL is passed to
pcre2_substitute(). After a successful substitution, the modified
string is output, preceded by the number of replacements. This may be
zero if there were no matches. Here is a simple example of a substitu-
tion test:
Unlike subject strings, pcre2test does not process replacement strings
for escape sequences. In UTF mode, a replacement string is checked to
see if it is a valid UTF-8 string. If so, it is correctly converted to
a UTF string of the appropriate code unit width. If it is not a valid
UTF-8 string, the individual code units are copied directly. This pro-
vides a means of passing an invalid UTF-8 string for testing purposes.
The following modifiers set options (in additional to the normal match
options) for pcre2_substitute():
global PCRE2_SUBSTITUTE_GLOBAL
substitute_extended PCRE2_SUBSTITUTE_EXTENDED
substitute_overflow_length PCRE2_SUBSTITUTE_OVERFLOW_LENGTH
substitute_unknown_unset PCRE2_SUBSTITUTE_UNKNOWN_UNSET
substitute_unset_empty PCRE2_SUBSTITUTE_UNSET_EMPTY
After a successful substitution, the modified string is output, pre-
ceded by the number of replacements. This may be zero if there were no
matches. Here is a simple example of a substitution test:
/abc/replace=xxx
=abc=abc=
@ -1031,12 +1051,13 @@ SUBJECT MODIFIERS
=abc=abc=\=global
2: =xxx=xxx=
Subject and replacement strings should be kept relatively short for
substitution tests, as fixed-size buffers are used. To make it easy to
test for buffer overflow, if the replacement string starts with a num-
ber in square brackets, that number is passed to pcre2_substitute() as
the size of the output buffer, with the replacement string starting at
the next character. Here is an example that tests the edge case:
Subject and replacement strings should be kept relatively short (fewer
than 256 characters) for substitution tests, as fixed-size buffers are
used. To make it easy to test for buffer overflow, if the replacement
string starts with a number in square brackets, that number is passed
to pcre2_substitute() as the size of the output buffer, with the
replacement string starting at the next character. Here is an example
that tests the edge case:
/abc/
123abc123\=replace=[10]XYZ
@ -1044,6 +1065,19 @@ SUBJECT MODIFIERS
123abc123\=replace=[9]XYZ
Failed: error -47: no more memory
The default action of pcre2_substitute() is to return
PCRE2_ERROR_NOMEMORY when the output buffer is too small. However, if
the PCRE2_SUBSTITUTE_OVERFLOW_LENGTH option is set (by using the sub-
stitute_overflow_length modifier), pcre2_substitute() continues to go
through the motions of matching and substituting, in order to compute
the size of buffer that is required. When this happens, pcre2test shows
the required buffer length (which includes space for the trailing zero)
as part of the error message. For example:
/abc/substitute_overflow_length
123abc123\=replace=[9]XYZ
Failed: error -47: no more memory: 10 code units are needed
A replacement string is ignored with POSIX and DFA matching. Specifying
partial matching provokes an error return ("bad option value") from
pcre2_substitute().
@ -1471,5 +1505,5 @@ AUTHOR
REVISION
Last updated: 05 November 2015
Last updated: 12 December 2015
Copyright (c) 1997-2015 University of Cambridge.

View File

@ -44,7 +44,7 @@ POSSIBILITY OF SUCH DAMAGE.
#define PCRE2_MAJOR 10
#define PCRE2_MINOR 21
#define PCRE2_PRERELEASE -RC1
#define PCRE2_DATE 2015-07-06
#define PCRE2_DATE 2015-12-15
/* When an application links to a PCRE DLL in Windows, the symbols that are
imported have to be identified as such. When building PCRE2, the appropriate