Add --disable-pcre2grep-callout-fork configuration setting.

CMakeLists.txt

@@ -83,6 +83,7 @@
 # 2018-06-19 PH added checks for stdint.h and inttypes.h (later removed)
 # 2018-06-27 PH added Daniel's patch to increase the stack for MSVC
 # 2018-11-14 PH removed unnecessary checks for stdint.h and inttypes.h
+# 2018-11-16 PH added PCRE2GREP_SUPPORT_CALLOUT_FORK support and tidied
 
 PROJECT(PCRE2 C)
 
@@ -136,7 +137,7 @@ OPTION(PCRE2_BUILD_PCRE2_32 "Build 32 bit PCRE2 library" OFF)
 
 OPTION(PCRE2_DEBUG "Include debugging code" OFF)
 
-OPTION(DISABLE_PERCENT_ZT "Disable the use of %zu and %td (rarely needed)" OFF)
+OPTION(PCRE2_DISABLE_PERCENT_ZT "Disable the use of %zu and %td (rarely needed)" OFF)
 
 SET(PCRE2_EBCDIC OFF CACHE BOOL
     "Use EBCDIC coding instead of ASCII. (This is rarely used outside of mainframe systems.)")
@@ -177,12 +178,15 @@ SET(PCRE2_SUPPORT_JIT OFF CACHE BOOL
 SET(PCRE2_SUPPORT_JIT_SEALLOC OFF CACHE BOOL
     "Enable SELinux compatible execmem allocator in JIT.")
 
-SET(PCRE2_SUPPORT_PCRE2GREP_JIT ON CACHE BOOL
+SET(PCRE2GREP_SUPPORT_JIT ON CACHE BOOL
     "Enable use of Just-in-time compiling in pcre2grep.")
 
-SET(PCRE2_SUPPORT_PCRE2GREP_CALLOUT ON CACHE BOOL
+SET(PCRE2GREP_SUPPORT_CALLOUT ON CACHE BOOL
     "Enable callout string support in pcre2grep.")
 
+SET(PCRE2GREP_SUPPORT_CALLOUT_FORK ON CACHE BOOL
+    "Enable callout string fork support in pcre2grep.")
+
 SET(PCRE2_SUPPORT_UNICODE ON CACHE BOOL
     "Enable support for Unicode and UTF-8/UTF-16/UTF-32 encoding.")
 
@@ -301,18 +305,25 @@ IF(PCRE2_SUPPORT_JIT_SEALLOC)
         SET(SLJIT_PROT_EXECUTABLE_ALLOCATOR 1)
 ENDIF(PCRE2_SUPPORT_JIT_SEALLOC)
 
-IF(PCRE2_SUPPORT_PCRE2GREP_JIT)
+IF(PCRE2GREP_SUPPORT_JIT)
         SET(SUPPORT_PCRE2GREP_JIT 1)
-ENDIF(PCRE2_SUPPORT_PCRE2GREP_JIT)
+ENDIF(PCRE2GREP_SUPPORT_JIT)
 
-IF(PCRE2_SUPPORT_PCRE2GREP_CALLOUT)
+IF(PCRE2GREP_SUPPORT_CALLOUT)
         SET(SUPPORT_PCRE2GREP_CALLOUT 1)
-ENDIF(PCRE2_SUPPORT_PCRE2GREP_CALLOUT)
+        IF(PCRE2GREP_SUPPORT_CALLOUT_FORK)
+                SET(SUPPORT_PCRE2GREP_CALLOUT_FORK 1)
+        ENDIF(PCRE2GREP_SUPPORT_CALLOUT_FORK)
+ENDIF(PCRE2GREP_SUPPORT_CALLOUT)
 
 IF(PCRE2_SUPPORT_VALGRIND)
         SET(SUPPORT_VALGRIND 1)
 ENDIF(PCRE2_SUPPORT_VALGRIND)
 
+IF(PCRE2_DISABLE_PERCENT_ZT)
+        SET(DISABLE_PERCENT_ZT 1)
+ENDIF(PCRE2_DISABLE_PERCENT_ZT)         
+
 # This next one used to reference ${READLINE_LIBRARY})
 # but I was advised to add the NCURSES test as well, along with
 # some modifications to cmake/FindReadline.cmake which should
@@ -802,10 +813,11 @@ IF(PCRE2_SHOW_REPORT)
   MESSAGE(STATUS "  Build shared libs ............... : ${BUILD_SHARED_LIBS}")
   MESSAGE(STATUS "  Build static libs ............... : ${BUILD_STATIC_LIBS}")
   MESSAGE(STATUS "  Build pcre2grep ................. : ${PCRE2_BUILD_PCRE2GREP}")
-  MESSAGE(STATUS "  Enable JIT in pcre2grep ......... : ${PCRE2_SUPPORT_PCRE2GREP_JIT}")
+  MESSAGE(STATUS "  Enable JIT in pcre2grep ......... : ${PCRE2GREP_SUPPORT_JIT}")
-  MESSAGE(STATUS "  Enable callouts in pcre2grep .... : ${PCRE2_SUPPORT_PCRE2GREP_CALLOUT}")
+  MESSAGE(STATUS "  Enable callouts in pcre2grep .... : ${PCRE2GREP_SUPPORT_CALLOUT}")
+  MESSAGE(STATUS "  Enable callout fork in pcre2grep. : ${PCRE2GREP_SUPPORT_CALLOUT_FORK}")
   MESSAGE(STATUS "  Buffer size for pcre2grep ....... : ${PCRE2GREP_BUFSIZE}")
-  MESSAGE(STATUS "  Build tests (implies pcre2test  . : ${PCRE2_BUILD_TESTS}")
+  MESSAGE(STATUS "  Build tests (implies pcre2test .. : ${PCRE2_BUILD_TESTS}")
   MESSAGE(STATUS "               and pcre2grep)")
   IF(ZLIB_FOUND)
     MESSAGE(STATUS "  Link pcre2grep with libz ........ : ${PCRE2_SUPPORT_LIBZ}")
@@ -828,6 +840,11 @@ IF(PCRE2_SHOW_REPORT)
     MESSAGE(STATUS "  Link pcre2test with libreadline . : Library not found" )
   ENDIF(READLINE_FOUND)
   MESSAGE(STATUS "  Support Valgrind .................: ${PCRE2_SUPPORT_VALGRIND}")
+  IF(PCRE2_DISABLE_PERCENT_ZT)
+    MESSAGE(STATUS "  Use %zu and %td ..................: OFF" )
+  ELSE(PCRE2_DISABLE_PERCENT_ZT)   
+    MESSAGE(STATUS "  Use %zu and %td ..................: AUTO" )
+  ENDIF(PCRE2_DISABLE_PERCENT_ZT)   
 
   IF(MINGW AND NOT PCRE2_STATIC)
     MESSAGE(STATUS "  Non-standard dll names (prefix) . : ${NON_STANDARD_LIB_PREFIX}")

ChangeLog

@@ -73,6 +73,10 @@ forcibly disable the use of %zu and %td in formatting strings because there is
 at least one version of VMS that claims to be C99 but does not support these 
 modifiers.
 
+18. Added --disable-pcre2grep-callout-fork, which restricts the callout support 
+in pcre2grep to the inbuilt echo facility. This may be useful in environments 
+that do not support fork().
+
 
 Version 10.32 10-September-2018
 -------------------------------

Makefile.am

@@ -625,6 +625,7 @@ EXTRA_DIST += \
   testdata/grepoutput \
   testdata/grepoutput8 \
   testdata/grepoutputC \
+  testdata/grepoutputCN \
   testdata/grepoutputN \
   testdata/greppatN4 \
   testdata/testinput1 \

RunGrepTest

@@ -732,16 +732,24 @@ fi
 $cf $srcdir/testdata/grepoutputN testtrygrep
 if [ $? != 0 ] ; then exit 1; fi
 
-# If pcre2grep supports script callouts, run some tests on them.
+# If pcre2grep supports script callouts, run some tests on them. It is possible
+# to restrict these callouts to the non-fork case, either for security, or for
+# environments that do not support fork(). This is handled by comparing to a
+# different output.
 
-if $valgrind $vjs $pcre2grep --help | $valgrind $vjs $pcre2grep -q 'Callout scripts in patterns are supported'; then
+if $valgrind $vjs $pcre2grep --help | $valgrind $vjs $pcre2grep -q 'callout scripts in patterns are supported'; then
   echo "Testing pcre2grep script callouts"
   $valgrind $vjs $pcre2grep '(T)(..(.))(?C"/bin/echo|Arg1: [$1] [$2] [$3]|Arg2: $|${1}$| ($4) ($14) ($0)")()' $srcdir/testdata/grepinputv >testtrygrep
   $valgrind $vjs $pcre2grep '(T)(..(.))()()()()()()()(..)(?C"/bin/echo|Arg1: [$11] [${11}]")' $srcdir/testdata/grepinputv >>testtrygrep
   $valgrind $vjs $pcre2grep '(T)(?C"|$0:$1$n")' $srcdir/testdata/grepinputv >>testtrygrep
   $valgrind $vjs $pcre2grep '(T)(?C"|$1$n")(*F)' $srcdir/testdata/grepinputv >>testtrygrep
-  # The above has no newline, which 'diff -ub' ignores, so add one.
+
-  $cf $srcdir/testdata/grepoutputC testtrygrep
+  if $valgrind $vjs $pcre2grep --help | $valgrind $vjs $pcre2grep -q 'Non-fork callout scripts in patterns are supported'; then
+    $cf $srcdir/testdata/grepoutputCN testtrygrep
+  else
+    $cf $srcdir/testdata/grepoutputC testtrygrep
+  fi
+ 
   if [ $? != 0 ] ; then exit 1; fi
 else
   echo "Script callouts are not supported"

RunGrepTest.bat

@@ -653,14 +653,19 @@ if ERRORLEVEL 1 exit /b 1
 
 :: If pcre2grep supports script callouts, run some tests on them.
 
-%pcre2grep% --help | %pcre2grep% -q "Callout scripts in patterns are supported"
+%pcre2grep% --help | %pcre2grep% -q "callout scripts in patterns are supported"
 if %ERRORLEVEL% equ 0 (
   echo Testing pcre2grep script callouts
   %pcre2grep% "(T)(..(.))(?C'cmd|/c echo|Arg1: [$1] [$2] [$3]|Arg2: ^$|${1}^$| ($4) ($14) ($0)')()" %srcdir%/testdata/grepinputv >testtrygrep
   %pcre2grep% "(T)(..(.))()()()()()()()(..)(?C'cmd|/c echo|Arg1: [$11] [${11}]')" %srcdir%/testdata/grepinputv >>testtrygrep
   %pcre2grep% "(T)(?C'|$0:$1$n')" %srcdir%/testdata/grepinputv >>testtrygrep
   %pcre2grep% "(T)(?C'|$1$n')(*F)" %srcdir%/testdata/grepinputv >>testtrygrep
-  %cf% %srcdir%\testdata\grepoutputC testtrygrep %cfout%
+  %pcre2grep% --help | %pcre2grep% -q "Non-script callout scripts in patterns are supported"
+  if %ERRORLEVEL% equ 0 (
+    %cf% %srcdir%\testdata\grepoutputCN testtrygrep %cfout%
+  ) else (
+    %cf% %srcdir%\testdata\grepoutputC testtrygrep %cfout%
+  )
   if ERRORLEVEL 1 exit /b 1
 ) else (
   echo Script callouts are not supported

config-cmake.h.in

@@ -28,6 +28,8 @@
 #cmakedefine SUPPORT_JIT 1
 #cmakedefine SLJIT_PROT_EXECUTABLE_ALLOCATOR 1
 #cmakedefine SUPPORT_PCRE2GREP_JIT 1
+#cmakedefine SUPPORT_PCRE2GREP_CALLOUT 1
+#cmakedefine SUPPORT_PCRE2GREP_CALLOUT_FORK 1
 #cmakedefine SUPPORT_UNICODE 1
 #cmakedefine SUPPORT_VALGRIND 1
 

configure.ac

@@ -173,6 +173,12 @@ AC_ARG_ENABLE(pcre2grep-callout,
                              [disable callout script support in pcre2grep]),
               , enable_pcre2grep_callout=yes)
 
+# Handle --disable-pcre2grep-callout-fork (enabled by default)
+AC_ARG_ENABLE(pcre2grep-callout-fork,
+              AS_HELP_STRING([--disable-pcre2grep-callout-fork],
+                             [disable callout script fork support in pcre2grep]),
+              , enable_pcre2grep_callout_fork=yes)
+
 # Handle --enable-rebuild-chartables
 AC_ARG_ENABLE(rebuild-chartables,
               AS_HELP_STRING([--enable-rebuild-chartables],
@@ -630,13 +636,21 @@ if test "$enable_pcre2grep_jit" = "yes"; then
 fi
 
 if test "$enable_pcre2grep_callout" = "yes"; then
-  if test "$HAVE_WINDOWS_H" != "1"; then
+  if test "$enable_pcre2grep_callout_fork" = "yes"; then
-    if test "$HAVE_SYS_WAIT_H" != "1"; then
+    if test "$HAVE_WINDOWS_H" != "1"; then
-      AC_MSG_ERROR([Callout script support needs sys/wait.h.])
+      if test "$HAVE_SYS_WAIT_H" != "1"; then
+        AC_MSG_ERROR([Callout script support needs sys/wait.h.])
+      fi
     fi
+    AC_DEFINE([SUPPORT_PCRE2GREP_CALLOUT_FORK], [], [
+      Define to any value to enable fork support in pcre2grep callout scripts.
+      This will have no effect unless SUPPORT_PCRE2GREP_CALLOUT is also 
+      defined.])  
   fi
   AC_DEFINE([SUPPORT_PCRE2GREP_CALLOUT], [], [
     Define to any value to enable callout script support in pcre2grep.])
+else
+  enable_pcre2grep_callout_fork="no"     
 fi
 
 if test "$enable_unicode" = "yes"; then
@@ -1038,6 +1052,7 @@ $PACKAGE-$VERSION configuration summary:
     Build static libs .................. : ${enable_static}
     Use JIT in pcre2grep ............... : ${enable_pcre2grep_jit}
     Enable callouts in pcre2grep ....... : ${enable_pcre2grep_callout}
+    Enable fork in pcre2grep callouts .. : ${enable_pcre2grep_callout_fork} 
     Initial buffer size for pcre2grep .. : ${with_pcre2grep_bufsize}
     Maximum buffer size for pcre2grep .. : ${with_pcre2grep_max_bufsize}
     Link pcre2grep with libz ........... : ${enable_pcre2grep_libz}

doc/html/pcre2grep.html

@@ -853,10 +853,12 @@ character. Otherwise <b>pcre2grep</b> will assume that it has no data.
 <P>
 <b>pcre2grep</b> has, by default, support for calling external programs or
 scripts or echoing specific strings during matching by making use of PCRE2's
-callout facility. However, this support can be disabled when <b>pcre2grep</b> is
+callout facility. However, this support can be completely or partially disabled
-built. You can find out whether your binary has support for callouts by running
+when <b>pcre2grep</b> is built. You can find out whether your binary has support
-it with the <b>--help</b> option. If the support is not enabled, all callouts in
+for callouts by running it with the <b>--help</b> option. If callout support is
-patterns are ignored by <b>pcre2grep</b>.
+completely disabled, all callouts in patterns are ignored by <b>pcre2grep</b>.
+If the facility is partially disabled, calling external programs is not
+supported, and callouts that request it are ignored.
 </P>
 <P>
 A callout in a PCRE2 pattern is of the form (?C&#60;arg&#62;) where the argument is
@@ -869,8 +871,9 @@ only callouts with string arguments are useful.
 Calling external programs or scripts
 </b><br>
 <P>
-If the callout string does not start with a pipe (vertical bar) character, it
+This facility can be independently disabled when <b>pcre2grep</b> is built. If
-is parsed into a list of substrings separated by pipe characters. The first
+the callout string does not start with a pipe (vertical bar) character, it is
+parsed into a list of substrings separated by pipe characters. The first
 substring must be an executable name, with the following substrings specifying
 arguments:
 <pre>
@@ -910,14 +913,15 @@ matcher backtracks in the normal way.
 Echoing a specific string
 </b><br>
 <P>
-If the callout string starts with a pipe (vertical bar) character, the rest of
+This facility is always available, provided that callouts were not completely
-the string is written to the output, having been passed through the same escape
+disabled when <b>pcre2grep</b> was built. If the callout string starts with a
-processing as text from the --output option. This provides a simple echoing
+pipe (vertical bar) character, the rest of the string is written to the output,
-facility that avoids calling an external program or script. No terminator is
+having been passed through the same escape processing as text from the --output
-added to the string, so if you want a newline, you must include it explicitly.
+option. This provides a simple echoing facility that avoids calling an external
-Matching continues normally after the string is output. If you want to see only
+program or script. No terminator is added to the string, so if you want a
-the callout output but not any output from an actual match, you should end the
+newline, you must include it explicitly. Matching continues normally after the
-relevant pattern with (*FAIL).
+string is output. If you want to see only the callout output but not any output
+from an actual match, you should end the relevant pattern with (*FAIL).
 </P>
 <br><a name="SEC12" href="#TOC1">MATCHING ERRORS</a><br>
 <P>
@@ -962,7 +966,7 @@ Cambridge, England.
 </P>
 <br><a name="SEC16" href="#TOC1">REVISION</a><br>
 <P>
-Last updated: 24 February 2018
+Last updated: 17 November 2018
 <br>
 Copyright &copy; 1997-2018 University of Cambridge.
 <br>

doc/pcre2grep.1

@@ -1,4 +1,4 @@
-.TH PCRE2GREP 1 "24 February 2018" "PCRE2 10.32"
+.TH PCRE2GREP 1 "17 November 2018" "PCRE2 10.33"
 .SH NAME
 pcre2grep - a grep with Perl-compatible regular expressions.
 .SH SYNOPSIS
@@ -759,10 +759,12 @@ character. Otherwise \fBpcre2grep\fP will assume that it has no data.
 .sp
 \fBpcre2grep\fP has, by default, support for calling external programs or
 scripts or echoing specific strings during matching by making use of PCRE2's
-callout facility. However, this support can be disabled when \fBpcre2grep\fP is
+callout facility. However, this support can be completely or partially disabled
-built. You can find out whether your binary has support for callouts by running
+when \fBpcre2grep\fP is built. You can find out whether your binary has support
-it with the \fB--help\fP option. If the support is not enabled, all callouts in
+for callouts by running it with the \fB--help\fP option. If callout support is
-patterns are ignored by \fBpcre2grep\fP.
+completely disabled, all callouts in patterns are ignored by \fBpcre2grep\fP.
+If the facility is partially disabled, calling external programs is not
+supported, and callouts that request it are ignored.
 .P
 A callout in a PCRE2 pattern is of the form (?C<arg>) where the argument is
 either a number or a quoted string (see the
@@ -776,8 +778,9 @@ only callouts with string arguments are useful.
 .SS "Calling external programs or scripts"
 .rs
 .sp
-If the callout string does not start with a pipe (vertical bar) character, it
+This facility can be independently disabled when \fBpcre2grep\fP is built. If
-is parsed into a list of substrings separated by pipe characters. The first
+the callout string does not start with a pipe (vertical bar) character, it is
+parsed into a list of substrings separated by pipe characters. The first
 substring must be an executable name, with the following substrings specifying
 arguments:
 .sp
@@ -816,14 +819,15 @@ matcher backtracks in the normal way.
 .SS "Echoing a specific string"
 .rs
 .sp
-If the callout string starts with a pipe (vertical bar) character, the rest of
+This facility is always available, provided that callouts were not completely
-the string is written to the output, having been passed through the same escape
+disabled when \fBpcre2grep\fP was built. If the callout string starts with a
-processing as text from the --output option. This provides a simple echoing
+pipe (vertical bar) character, the rest of the string is written to the output,
-facility that avoids calling an external program or script. No terminator is
+having been passed through the same escape processing as text from the --output
-added to the string, so if you want a newline, you must include it explicitly.
+option. This provides a simple echoing facility that avoids calling an external
-Matching continues normally after the string is output. If you want to see only
+program or script. No terminator is added to the string, so if you want a
-the callout output but not any output from an actual match, you should end the
+newline, you must include it explicitly. Matching continues normally after the
-relevant pattern with (*FAIL).
+string is output. If you want to see only the callout output but not any output
+from an actual match, you should end the relevant pattern with (*FAIL).
 .
 .
 .SH "MATCHING ERRORS"
@@ -876,6 +880,6 @@ Cambridge, England.
 .rs
 .sp
 .nf
-Last updated: 24 February 2018
+Last updated: 17 November 2018
 Copyright (c) 1997-2018 University of Cambridge.
 .fi

doc/pcre2grep.txt

@@ -832,22 +832,26 @@ USING PCRE2'S CALLOUT FACILITY
 
        pcre2grep  has,  by  default,  support for calling external programs or
        scripts or echoing specific strings during matching by  making  use  of
-       PCRE2's  callout  facility.  However, this support can be disabled when
+       PCRE2's  callout  facility.  However, this support can be completely or
-       pcre2grep is built. You can find out whether your  binary  has  support
+       partially disabled when pcre2grep is built. You can  find  out  whether
-       for  callouts  by  running it with the --help option. If the support is
+       your  binary  has  support  for  callouts by running it with the --help
-       not enabled, all callouts in patterns are ignored by pcre2grep.
+       option. If callout support is completely disabled, all callouts in pat-
+       terns are ignored by pcre2grep.  If the facility is partially disabled,
+       calling external programs is not supported, and callouts  that  request
+       it are ignored.
 
-       A callout in a PCRE2 pattern is of the form (?C<arg>) where  the  argu-
+       A  callout  in a PCRE2 pattern is of the form (?C<arg>) where the argu-
-       ment  is either a number or a quoted string (see the pcre2callout docu-
+       ment is either a number or a quoted string (see the pcre2callout  docu-
-       mentation for details). Numbered callouts  are  ignored  by  pcre2grep;
+       mentation  for  details).  Numbered  callouts are ignored by pcre2grep;
        only callouts with string arguments are useful.
 
    Calling external programs or scripts
 
-       If the callout string does not start with a pipe (vertical bar) charac-
+       This facility can be independently disabled when pcre2grep is built. If
-       ter, it is parsed into a list of substrings separated by  pipe  charac-
+       the callout string does not start with a pipe (vertical bar) character,
-       ters.  The first substring must be an executable name, with the follow-
+       it is parsed into a list of substrings separated  by  pipe  characters.
-       ing substrings specifying arguments:
+       The first substring must be an executable name, with the following sub-
+       strings specifying arguments:
 
          executable_name|arg1|arg2|...
 
@@ -885,44 +889,45 @@ USING PCRE2'S CALLOUT FACILITY
 
    Echoing a specific string
 
-       If  the callout string starts with a pipe (vertical bar) character, the
+       This facility is always available, provided that callouts were not com-
-       rest of the string is written to the output, having been passed through
+       pletely disabled when pcre2grep was built. If the callout string starts
-       the  same escape processing as text from the --output option. This pro-
+       with a pipe (vertical bar) character, the rest of the string is written
-       vides a simple echoing facility that avoids calling an external program
+       to the output, having been passed through the same escape processing as
-       or  script. No terminator is added to the string, so if you want a new-
+       text  from the --output option. This provides a simple echoing facility
-       line, you must include  it  explicitly.   Matching  continues  normally
+       that avoids calling an external program or  script.  No  terminator  is
-       after  the string is output. If you want to see only the callout output
+       added  to  the  string,  so  if you want a newline, you must include it
-       but not any output from an actual match, you should  end  the  relevant
+       explicitly. Matching continues normally after the string is output.  If
-       pattern with (*FAIL).
+       you  want  to  see  only  the callout output but not any output from an
+       actual match, you should end the relevant pattern with (*FAIL).
 
 
 MATCHING ERRORS
 
-       It  is  possible  to supply a regular expression that takes a very long
+       It is possible to supply a regular expression that takes  a  very  long
-       time to fail to match certain lines.  Such  patterns  normally  involve
+       time  to  fail  to  match certain lines. Such patterns normally involve
-       nested  indefinite repeats, for example: (a+)*\d when matched against a
+       nested indefinite repeats, for example: (a+)*\d when matched against  a
-       line of a's with no final digit. The  PCRE2  matching  function  has  a
+       line  of  a's  with  no  final digit. The PCRE2 matching function has a
-       resource  limit that causes it to abort in these circumstances. If this
+       resource limit that causes it to abort in these circumstances. If  this
-       happens, pcre2grep outputs an error message and the  line  that  caused
+       happens,  pcre2grep  outputs  an error message and the line that caused
-       the  problem  to  the  standard error stream. If there are more than 20
+       the problem to the standard error stream. If there  are  more  than  20
        such errors, pcre2grep gives up.
 
-       The --match-limit option of pcre2grep can be used to  set  the  overall
+       The  --match-limit  option  of pcre2grep can be used to set the overall
-       resource  limit.  There are also other limits that affect the amount of
+       resource limit. There are also other limits that affect the  amount  of
-       memory used during matching; see the  discussion  of  --heap-limit  and
+       memory  used  during  matching;  see the discussion of --heap-limit and
        --depth-limit above.
 
 
 DIAGNOSTICS
 
        Exit status is 0 if any matches were found, 1 if no matches were found,
-       and 2 for syntax errors, overlong lines, non-existent  or  inaccessible
+       and  2  for syntax errors, overlong lines, non-existent or inaccessible
-       files  (even if matches were found in other files) or too many matching
+       files (even if matches were found in other files) or too many  matching
        errors. Using the -s option to suppress error messages about inaccessi-
        ble files does not affect the return code.
 
-       When   run  under  VMS,  the  return  code  is  placed  in  the  symbol
+       When  run  under  VMS,  the  return  code  is  placed  in  the   symbol
-       PCRE2GREP_RC because VMS  does  not  distinguish  between  exit(0)  and
+       PCRE2GREP_RC  because  VMS  does  not  distinguish  between exit(0) and
        exit(1).
 
 
@@ -940,5 +945,5 @@ AUTHOR
 
 REVISION
 
-       Last updated: 24 February 2018
+       Last updated: 17 November 2018
        Copyright (c) 1997-2018 University of Cambridge.

src/config.h.in

@@ -290,6 +290,11 @@ sure both macros are undefined; an emulation function will then be used. */
 /* Define to any value to enable callout script support in pcre2grep. */
 #undef SUPPORT_PCRE2GREP_CALLOUT
 
+/* Define to any value to enable fork support in pcre2grep callout scripts.
+   This will have no effect unless SUPPORT_PCRE2GREP_CALLOUT is also defined.
+   */
+#undef SUPPORT_PCRE2GREP_CALLOUT_FORK
+
 /* Define to any value to enable JIT support in pcre2grep. Note that this will
    have no effect unless SUPPORT_JIT is also defined. */
 #undef SUPPORT_PCRE2GREP_JIT

src/pcre2grep.c

@@ -73,7 +73,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <fcntl.h>             /* For _O_BINARY */
 #endif
 
-#ifdef SUPPORT_PCRE2GREP_CALLOUT
+#if defined(SUPPORT_PCRE2GREP_CALLOUT) && defined(SUPPORT_PCRE2GREP_CALLOUT_FORK)
 #ifdef WIN32
 #include <process.h>
 #else
@@ -1133,7 +1133,11 @@ printf("Search for PATTERN in each FILE or standard input." STDOUT_NL);
 printf("PATTERN must be present if neither -e nor -f is used." STDOUT_NL);
 
 #ifdef SUPPORT_PCRE2GREP_CALLOUT
-printf("Callout scripts in patterns are supported." STDOUT_NL);
+#ifdef SUPPORT_PCRE2GREP_CALLOUT_FORK
+printf("All callout scripts in patterns are supported." STDOUT_NL);
+#else
+printf("Non-fork callout scripts in patterns are supported." STDOUT_NL);
+#endif
 #else
 printf("Callout scripts are not supported in this pcre2grep." STDOUT_NL);
 #endif
@@ -2017,10 +2021,10 @@ return printed;
 *        Parse and execute callout scripts       *
 *************************************************/
 
-/* This function parses a callout string block and executes the
+/* If SUPPORT_PCRE2GREP_CALLOUT_FORK is defined, this function parses a callout
-program specified by the string. The string is a list of substrings
+string block and executes the program specified by the string. The string is a
-separated by pipe characters. The first substring represents the
+list of substrings separated by pipe characters. The first substring represents
-executable name, and the following substrings specify the arguments:
+the executable name, and the following substrings specify the arguments:
 
   program_name|param1|param2|...
 
@@ -2037,8 +2041,9 @@ follows:
   dollar or $| replaced by a pipe character.
 
 Alternatively, if string starts with pipe, the remainder is taken as an output
-string, same as --output. In this case, --om-separator is used to separate each
+string, same as --output. This is the only form that is supported if 
-callout, defaulting to newline.
+SUPPORT_PCRE2GREP_FORK is not defined. In this case, --om-separator is used to
+separate each callout, defaulting to newline.
 
 Example:
 
@@ -2066,6 +2071,8 @@ PCRE2_SPTR string = calloutptr->callout_string;
 PCRE2_SPTR subject = calloutptr->subject;
 PCRE2_SIZE *ovector = calloutptr->offset_vector;
 PCRE2_SIZE capture_top = calloutptr->capture_top;
+
+#ifdef SUPPORT_PCRE2GREP_CALLOUT_FORK
 PCRE2_SIZE argsvectorlen = 2;
 PCRE2_SIZE argslen = 1;
 char *args;
@@ -2076,10 +2083,12 @@ char **argsvectorptr;
 pid_t pid;
 #endif
 int result = 0;
+#endif  /* SUPPORT_PCRE2GREP_CALLOUT_FORK */
 
 (void)unused;   /* Avoid compiler warning */
 
 /* Only callout with strings are supported. */
+
 if (string == NULL || length == 0) return 0;
 
 /* If there's no command, output the remainder directly. */
@@ -2091,6 +2100,10 @@ if (*string == '|')
   (void)display_output_text(string, TRUE, subject, ovector, capture_top);
   return 0;
   }
+  
+#ifndef SUPPORT_PCRE2GREP_CALLOUT_FORK
+return 0;
+#else
 
 /* Checking syntax and compute the number of string fragments. Callout strings
 are ignored in case of a syntax error. */
@@ -2294,9 +2307,9 @@ free(argsvector);
 continues) or non-zero (match fails). */
 
 return result != 0;
+#endif  /* SUPPORT_PCRE2GREP_CALLOUT_FORK */
 }
-
+#endif  /* SUPPORT_PCRE2GREP_CALLOUT */
-#endif
 
 
 

testdata/grepoutputCN

@@ -0,0 +1,30 @@
+The quick brown
+This time it jumps and jumps and jumps.
+This line contains \E and (regex) *meta* [characters].
+The word is cat in this line
+The caterpillar sat on the mat
+The snowcat is not an animal
+The quick brown
+This time it jumps and jumps and jumps.
+This line contains \E and (regex) *meta* [characters].
+The word is cat in this line
+The caterpillar sat on the mat
+The snowcat is not an animal
+0:T
+The quick brown
+0:T
+This time it jumps and jumps and jumps.
+0:T
+This line contains \E and (regex) *meta* [characters].
+0:T
+The word is cat in this line
+0:T
+The caterpillar sat on the mat
+0:T
+The snowcat is not an animal
+T
+T
+T
+T
+T
+T