X-Git-Url: https://git.exim.org/users/heiko/exim.git/blobdiff_plain/8ac170f35ed82789928f9e94beaa38991761a88c..7c6d71af3bd2663fed446b87f9231f39e818d93b:/doc/doc-txt/pcretest.txt diff --git a/doc/doc-txt/pcretest.txt b/doc/doc-txt/pcretest.txt index 384a6c38f..d93ec26d1 100644 --- a/doc/doc-txt/pcretest.txt +++ b/doc/doc-txt/pcretest.txt @@ -6,14 +6,13 @@ is built with Exim. PCRETEST(1) PCRETEST(1) - NAME pcretest - a program for testing Perl-compatible regular expressions. + SYNOPSIS - pcretest [-C] [-d] [-dfa] [-i] [-m] [-o osize] [-p] [-t] [source] - [destination] + pcretest [options] [source] [destination] pcretest was written as a test program for the PCRE regular expression library itself, but it can also be used for experimenting with regular @@ -25,18 +24,24 @@ SYNOPSIS OPTIONS + -b Behave as if each regex has the /B (show bytecode) modifier; + the internal form is output after compilation. + -C Output the version number of the PCRE library, and all avail- - able information about the optional features that are + able information about the optional features that are included, and then exit. - -d Behave as if each regex has the /D (debug) modifier; the - internal form is output after compilation. + -d Behave as if each regex has the /D (debug) modifier; the + internal form and information about the compiled pattern is + output after compilation; -d is equivalent to -b -i. -dfa Behave as if each data line contains the \D escape sequence; this causes the alternative matching function, pcre_dfa_exec(), to be used instead of the standard pcre_exec() function (more detail is given below). + -help Output a brief summary these options and then exit. + -i Behave as if each regex has the /I modifier; information about the compiled pattern is given after compilation. @@ -46,20 +51,34 @@ OPTIONS pcretest, -s is a synonym for -m. -o osize Set the number of elements in the output vector that is used - when calling pcre_exec() to be osize. The default value is - 45, which is enough for 14 capturing subexpressions. The vec- - tor size can be changed for individual matching calls by - including \O in the data line (see below). + when calling pcre_exec() or pcre_dfa_exec() to be osize. The + default value is 45, which is enough for 14 capturing subex- + pressions for pcre_exec() or 22 different matches for + pcre_dfa_exec(). The vector size can be changed for individ- + ual matching calls by including \O in the data line (see + below). -p Behave as if each regex has the /P modifier; the POSIX wrap- per API is used to call PCRE. None of the other options has any effect when -p is set. + -q Do not output the version number of pcretest at the start of + execution. + + -S size On Unix-like systems, set the size of the runtime stack to + size megabytes. + -t Run each compile, study, and match many times with a timer, and output resulting time per compile or match (in millisec- onds). Do not set -m with -t, because you will then get the size output a zillion times, and the timing will be dis- - torted. + torted. You can control the number of iterations that are + used for timing by following -t with a number (as a separate + item on the command line). For example, "-t 1000" would iter- + ate 1000 times. The default is to iterate 500000 times. + + -tm This is like -t except that it times only the matching phase, + not the compile or study phases. DESCRIPTION @@ -76,13 +95,15 @@ DESCRIPTION ber of data lines to be matched against the pattern. Each data line is matched separately and independently. If you want to - do multiple-line matches, you have to use the \n escape sequence in a - single line of input to encode the newline characters. The maximum - length of data line is 30,000 characters. + do multi-line matches, you have to use the \n escape sequence (or \r or + \r\n, etc., depending on the newline setting) in a single line of input + to encode the newline sequences. There is no limit on the length of + data lines; the input buffer is automatically extended if it is too + small. An empty line signals the end of the data lines, at which point a new regular expression is read. The regular expressions are given enclosed - in any non-alphanumeric delimiters other than backslash, for example + in any non-alphanumeric delimiters other than backslash, for example: /(a|bc)x+yz/ @@ -130,38 +151,64 @@ PATTERN MODIFIERS The following table shows additional modifiers for setting PCRE options that do not correspond to anything in Perl: - /A PCRE_ANCHORED - /C PCRE_AUTO_CALLOUT - /E PCRE_DOLLAR_ENDONLY - /f PCRE_FIRSTLINE - /N PCRE_NO_AUTO_CAPTURE - /U PCRE_UNGREEDY - /X PCRE_EXTRA + /A PCRE_ANCHORED + /C PCRE_AUTO_CALLOUT + /E PCRE_DOLLAR_ENDONLY + /f PCRE_FIRSTLINE + /J PCRE_DUPNAMES + /N PCRE_NO_AUTO_CAPTURE + /U PCRE_UNGREEDY + /X PCRE_EXTRA + / PCRE_NEWLINE_CR + / PCRE_NEWLINE_LF + / PCRE_NEWLINE_CRLF + / PCRE_NEWLINE_ANYCRLF + / PCRE_NEWLINE_ANY + + Those specifying line ending sequencess are literal strings as shown. + This example sets multiline matching with CRLF as the line ending + sequence: + + /^abc/m + + Details of the meanings of these PCRE options are given in the pcreapi + documentation. + + Finding all matches in a string - Searching for all possible matches within each subject string can be - requested by the /g or /G modifier. After finding a match, PCRE is + Searching for all possible matches within each subject string can be + requested by the /g or /G modifier. After finding a match, PCRE is called again to search the remainder of the subject string. The differ- ence between /g and /G is that the former uses the startoffset argument - to pcre_exec() to start searching at a new point within the entire - string (which is in effect what Perl does), whereas the latter passes - over a shortened substring. This makes a difference to the matching + to pcre_exec() to start searching at a new point within the entire + string (which is in effect what Perl does), whereas the latter passes + over a shortened substring. This makes a difference to the matching process if the pattern begins with a lookbehind assertion (including \b or \B). - If any call to pcre_exec() in a /g or /G sequence matches an empty - string, the next call is done with the PCRE_NOTEMPTY and PCRE_ANCHORED - flags set in order to search for another, non-empty, match at the same - point. If this second match fails, the start offset is advanced by - one, and the normal match is retried. This imitates the way Perl han- + If any call to pcre_exec() in a /g or /G sequence matches an empty + string, the next call is done with the PCRE_NOTEMPTY and PCRE_ANCHORED + flags set in order to search for another, non-empty, match at the same + point. If this second match fails, the start offset is advanced by + one, and the normal match is retried. This imitates the way Perl han- dles such cases when using the /g modifier or the split() function. + Other modifiers + There are yet more modifiers for controlling the way pcretest operates. - The /+ modifier requests that as well as outputting the substring that - matched the entire pattern, pcretest should in addition output the - remainder of the subject string. This is useful for tests where the + The /+ modifier requests that as well as outputting the substring that + matched the entire pattern, pcretest should in addition output the + remainder of the subject string. This is useful for tests where the subject contains multiple copies of the same substring. + The /B modifier is a debugging feature. It requests that pcretest out- + put a representation of the compiled byte code after compilation. Nor- + mally this information contains length and offset values; however, if + /Z is also present, this data is replaced by spaces. This is a special + feature for use in the automatic test scripts; it ensures that the same + output is generated for different internal link sizes. + The /L modifier must be followed directly by the name of a locale, for example, @@ -180,10 +227,8 @@ PATTERN MODIFIERS pattern. If the pattern is studied, the results of that are also out- put. - The /D modifier is a PCRE debugging feature, which also assumes /I. It - causes the internal form of compiled regular expressions to be output - after compilation. If the pattern was studied, the information returned - is also output. + The /D modifier is a PCRE debugging feature, and is equivalent to /BI, + that is, both the /B and the /I modifiers. The /F modifier causes pcretest to flip the byte order of the fields in the compiled pattern that contain 2-byte and 4-byte numbers. This @@ -225,20 +270,24 @@ DATA LINES nary" regular expressions, you probably don't need any of these. The following escapes are recognized: - \a alarm (= BEL) - \b backspace - \e escape - \f formfeed - \n newline - \r carriage return - \t tab - \v vertical tab + \a alarm (BEL, \x07) + \b backspace (\x08) + \e escape (\x27) + \f formfeed (\x0c) + \n newline (\x0a) + \qdd set the PCRE_MATCH_LIMIT limit to dd + (any number of digits) + \r carriage return (\x0d) + \t tab (\x09) + \v vertical tab (\x0b) \nnn octal character (up to 3 octal digits) \xhh hexadecimal character (up to 2 hex digits) \x{hh...} hexadecimal character, any number of digits in UTF-8 mode \A pass the PCRE_ANCHORED option to pcre_exec() + or pcre_dfa_exec() \B pass the PCRE_NOTBOL option to pcre_exec() + or pcre_dfa_exec() \Cdd call pcre_copy_substring() for substring dd after a successful match (number less than 32) \Cname call pcre_copy_named_substring() for substring @@ -262,19 +311,39 @@ DATA LINES ated by next non-alphanumeric character) \L call pcre_get_substringlist() after a successful match - \M discover the minimum MATCH_LIMIT setting + \M discover the minimum MATCH_LIMIT and + MATCH_LIMIT_RECURSION settings \N pass the PCRE_NOTEMPTY option to pcre_exec() + or pcre_dfa_exec() \Odd set the size of the output vector passed to pcre_exec() to dd (any number of digits) \P pass the PCRE_PARTIAL option to pcre_exec() or pcre_dfa_exec() + \Qdd set the PCRE_MATCH_LIMIT_RECURSION limit to dd + (any number of digits) \R pass the PCRE_DFA_RESTART option to pcre_dfa_exec() \S output details of memory get/free calls during matching \Z pass the PCRE_NOTEOL option to pcre_exec() + or pcre_dfa_exec() \? pass the PCRE_NO_UTF8_CHECK option to - pcre_exec() + pcre_exec() or pcre_dfa_exec() \>dd start the match at offset dd (any number of digits); this sets the startoffset argument for pcre_exec() + or pcre_dfa_exec() + \ pass the PCRE_NEWLINE_CR option to pcre_exec() + or pcre_dfa_exec() + \ pass the PCRE_NEWLINE_LF option to pcre_exec() + or pcre_dfa_exec() + \ pass the PCRE_NEWLINE_CRLF option to pcre_exec() + or pcre_dfa_exec() + \ pass the PCRE_NEWLINE_ANYCRLF option to pcre_exec() + or pcre_dfa_exec() + \ pass the PCRE_NEWLINE_ANY option to pcre_exec() + or pcre_dfa_exec() + + The escapes that specify line ending sequences are literal strings, + exactly as shown. No more than one newline setting should be present in + any data line. A backslash followed by anything else just escapes the anything else. If the very last character is a backslash, it is ignored. This gives a @@ -282,21 +351,25 @@ DATA LINES nates the data input. If \M is present, pcretest calls pcre_exec() several times, with dif- - ferent values in the match_limit field of the pcre_extra data struc- - ture, until it finds the minimum number that is needed for pcre_exec() - to complete. This number is a measure of the amount of recursion and - backtracking that takes place, and checking it out can be instructive. - For most simple matches, the number is quite small, but for patterns - with very large numbers of matching possibilities, it can become large - very quickly with increasing length of subject string. - - When \O is used, the value specified may be higher or lower than the + ferent values in the match_limit and match_limit_recursion fields of + the pcre_extra data structure, until it finds the minimum numbers for + each parameter that allow pcre_exec() to complete. The match_limit num- + ber is a measure of the amount of backtracking that takes place, and + checking it out can be instructive. For most simple matches, the number + is quite small, but for patterns with very large numbers of matching + possibilities, it can become large very quickly with increasing length + of subject string. The match_limit_recursion number is a measure of how + much stack (or, if PCRE is compiled with NO_RECURSE, how much heap) + memory is needed to complete the match attempt. + + When \O is used, the value specified may be higher or lower than the size set by the -O command line option (or defaulted to 45); \O applies only to the call of pcre_exec() for the line in which it appears. - If the /P modifier was present on the pattern, causing the POSIX wrap- - per API to be used, only \B and \Z have any effect, causing REG_NOTBOL - and REG_NOTEOL to be passed to regexec() respectively. + If the /P modifier was present on the pattern, causing the POSIX wrap- + per API to be used, the only option-setting sequences that have any + effect are \B and \Z, causing REG_NOTBOL and REG_NOTEOL, respectively, + to be passed to regexec(). The use of \x{hh...} to represent UTF-8 characters is not dependent on the use of the /8 modifier on the pattern. It is recognized always. @@ -332,7 +405,7 @@ DEFAULT OUTPUT FROM PCRETEST is an example of an interactive pcretest run. $ pcretest - PCRE version 5.00 07-Sep-2004 + PCRE version 7.0 30-Nov-2006 re> /^abc(\d+)/ data> abc123 @@ -343,16 +416,17 @@ DEFAULT OUTPUT FROM PCRETEST If the strings contain any non-printing characters, they are output as \0x escapes, or as \x{...} escapes if the /8 modifier was present on - the pattern. If the pattern has the /+ modifier, the output for sub- - string 0 is followed by the the rest of the subject string, identified - by "0+" like this: + the pattern. See below for the definition of non-printing characters. + If the pattern has the /+ modifier, the output for substring 0 is fol- + lowed by the the rest of the subject string, identified by "0+" like + this: re> /cat/+ data> cataract 0: cat 0+ aract - If the pattern has the /g or /G modifier, the results of successive + If the pattern has the /g or /G modifier, the results of successive matching attempts are output in sequence, like this: re> /\Bi(\w\w)/g @@ -366,16 +440,17 @@ DEFAULT OUTPUT FROM PCRETEST "No match" is output only if the first match attempt fails. - If any of the sequences \C, \G, or \L are present in a data line that - is successfully matched, the substrings extracted by the convenience + If any of the sequences \C, \G, or \L are present in a data line that + is successfully matched, the substrings extracted by the convenience functions are output with C, G, or L after the string number instead of a colon. This is in addition to the normal full list. The string length - (that is, the return from the extraction function) is given in paren- + (that is, the return from the extraction function) is given in paren- theses after each string for \C and \G. - Note that while patterns can be continued over several lines (a plain + Note that whereas patterns can be continued over several lines (a plain ">" prompt is used for continuations), data lines may not. However new- - lines can be included in data by means of the \n escape. + lines can be included in data by means of the \n escape (or \r, \r\n, + etc., depending on the newline sequence setting). OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION @@ -394,8 +469,8 @@ OUTPUT FROM THE ALTERNATIVE MATCHING FUNCTION (Using the normal matching function on this data finds only "tang".) The longest matching string is always given first (and numbered zero). - If /gP is present on the pattern, the search for further matches - resumes at the end of the longest match. For example: + If /g is present on the pattern, the search for further matches resumes + at the end of the longest match. For example: re> /(tang|tangerine|tan)/g data> yellow tangerine and tangy sultana\D @@ -418,7 +493,7 @@ RESTARTING AFTER A PARTIAL MATCH can restart the match with additional subject data by means of the \R escape sequence. For example: - re> /^?(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)$/ + re> /^\d?\d(jan|feb|mar|apr|may|jun|jul|aug|sep|oct|nov|dec)\d\d$/ data> 23ja\P\D Partial match: 23ja data> n05\R\D @@ -468,6 +543,18 @@ CALLOUTS the pcrecallout documentation. +NON-PRINTING CHARACTERS + + When pcretest is outputting text in the compiled version of a pattern, + bytes other than 32-126 are always treated as non-printing characters + are are therefore shown as hex escapes. + + When pcretest is outputting text that is a matched part of a subject + string, it behaves in the same way, unless a different locale has been + set for the pattern (using the /L modifier). In this case, the + isprint() function to distinguish printing and non-printing characters. + + SAVING AND RELOADING COMPILED PATTERNS The facilities described in this section are not available when the @@ -524,11 +611,20 @@ SAVING AND RELOADING COMPILED PATTERNS a file that is not in the correct format, the result is undefined. +SEE ALSO + + pcre(3), pcreapi(3), pcrecallout(3), pcrematching(3), pcrepartial(d), + pcrepattern(3), pcreprecompile(3). + + AUTHOR Philip Hazel - University Computing Service, - Cambridge CB2 3QG, England. + University Computing Service + Cambridge CB2 3QH, England. + + +REVISION -Last updated: 28 February 2005 -Copyright (c) 1997-2005 University of Cambridge. + Last updated: 24 April 2007 + Copyright (c) 1997-2007 University of Cambridge.