From 6e0dbefde3ddb0711e2b0961ee913084dc5e6a41 Mon Sep 17 00:00:00 2001

From: Pino Toscano <ptoscano@redhat.com>

Date: Tue, 19 Feb 2019 10:50:01 +0100

Subject: [PATCH] common/mlpcre: add offset flag for PCRE.matches

This way it is possible to change where the matching start, instead of

always assuming it is the beginning.

(cherry picked from commit 0ed2e5c14a302d15fd3b75ee2c1cb808a06cb746)

---

 common/mlpcre/PCRE.ml       |  2 +-

 common/mlpcre/PCRE.mli      |  5 ++++-

 common/mlpcre/pcre-c.c      | 16 +++++++++++++---

 common/mlpcre/pcre_tests.ml | 11 ++++++++---

 4 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/common/mlpcre/PCRE.ml b/common/mlpcre/PCRE.ml

index b054928f9..33074af1c 100644

--- a/common/mlpcre/PCRE.ml

+++ b/common/mlpcre/PCRE.ml

@@ -23,7 +23,7 @@ exception Error of string * int

 type regexp

 external compile : ?anchored:bool -> ?caseless:bool -> ?dotall:bool -> ?extended:bool -> ?multiline:bool -> string -> regexp = "guestfs_int_pcre_compile_byte" "guestfs_int_pcre_compile"

-external matches : regexp -> string -> bool = "guestfs_int_pcre_matches"

+external matches : ?offset:int -> regexp -> string -> bool = "guestfs_int_pcre_matches"

 external sub : int -> string = "guestfs_int_pcre_sub"

 external subi : int -> int * int = "guestfs_int_pcre_subi"

diff --git a/common/mlpcre/PCRE.mli b/common/mlpcre/PCRE.mli

index eacb6fd90..e10d512fc 100644

--- a/common/mlpcre/PCRE.mli

+++ b/common/mlpcre/PCRE.mli

@@ -62,7 +62,7 @@ val compile : ?anchored:bool -> ?caseless:bool -> ?dotall:bool -> ?extended:bool

     See pcreapi(3) for details of what they do.

     All flags default to false. *)

-val matches : regexp -> string -> bool

+val matches : ?offset:int -> regexp -> string -> bool

 (** Test whether the regular expression matches the string.  This

     returns true if the regexp matches or false otherwise.

@@ -71,6 +71,9 @@ val matches : regexp -> string -> bool

     or the thread/program exits.  You can call {!sub} to return

     these substrings.

+    The [?offset] flag is used to change the start of the search,

+    which by default is at the beginning of the string (position 0).

+

     This can raise {!Error} if PCRE returns an error. *)

 val sub : int -> string

diff --git a/common/mlpcre/pcre-c.c b/common/mlpcre/pcre-c.c

index 0762a8341..be054a004 100644

--- a/common/mlpcre/pcre-c.c

+++ b/common/mlpcre/pcre-c.c

@@ -121,6 +121,15 @@ is_Some_true (value v)

     Bool_val (Field (v, 0)) /* Some true */;

 }

+static int

+Optint_val (value intv, int defval)

+{

+  if (intv == Val_int (0))      /* None */

+    return defval;

+  else                          /* Some int */

+    return Int_val (Field (intv, 0));

+}

+

 value

 guestfs_int_pcre_compile (value anchoredv, value caselessv, value dotallv,

                           value extendedv, value multilinev,

@@ -165,9 +174,9 @@ guestfs_int_pcre_compile_byte (value *argv, int argn)

 }

 value

-guestfs_int_pcre_matches (value rev, value strv)

+guestfs_int_pcre_matches (value offsetv, value rev, value strv)

 {

-  CAMLparam2 (rev, strv);

+  CAMLparam3 (offsetv, rev, strv);

   pcre *re = Regexp_val (rev);

   struct last_match *m, *oldm;

   size_t len = caml_string_length (strv);

@@ -205,7 +214,8 @@ guestfs_int_pcre_matches (value rev, value strv)

     caml_raise_out_of_memory ();

   }

-  m->r = pcre_exec (re, NULL, m->subject, len, 0, 0, m->vec, veclen);

+  m->r = pcre_exec (re, NULL, m->subject, len, Optint_val (offsetv, 0), 0,

+                    m->vec, veclen);

   if (m->r < 0 && m->r != PCRE_ERROR_NOMATCH) {

     int ret = m->r;

     free_last_match (m);

diff --git a/common/mlpcre/pcre_tests.ml b/common/mlpcre/pcre_tests.ml

index 346019c40..3e5981107 100644

--- a/common/mlpcre/pcre_tests.ml

+++ b/common/mlpcre/pcre_tests.ml

@@ -30,9 +30,9 @@ let compile ?(anchored = false) ?(caseless = false)

           patt;

   PCRE.compile ~anchored ~caseless ~dotall ~extended ~multiline patt

-let matches re str =

-  eprintf "PCRE.matches %s ->%!" str;

-  let r = PCRE.matches re str in

+let matches ?(offset = 0) re str =

+  eprintf "PCRE.matches %s, %d ->%!" str offset;

+  let r = PCRE.matches ~offset re str in

   eprintf " %b\n%!" r;

   r

@@ -103,6 +103,11 @@ let () =

     assert (subi 1 = (2, 3));

     assert (subi 2 = (3, 3));

+    assert (matches ~offset:5 re0 "aaabcabc" = true);

+    assert (sub 0 = "ab");

+

+    assert (matches ~offset:5 re0 "aaabcbaac" = false);

+

     assert (replace re0 "dd" "abcabcaabccca" = "ddcabcaabccca");

     assert (replace ~global:true re0 "dd" "abcabcaabccca" = "ddcddcddccca");

-- 

2.24.1