From 2a294ddadb4b8411b89db2af93cdf0094b068e59 Mon Sep 17 00:00:00 2001
From: Philip Hazel <Philip.Hazel@gmail.com>
Date: Sun, 28 Nov 2021 16:38:36 +0000
Subject: [PATCH] Add check for NULL subject to POSIX regexec().

---
 ChangeLog        | 2 ++
 src/pcre2posix.c | 2 ++
 src/pcre2test.c  | 6 ++++--
 3 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 1a92b9a..a9e90b1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -30,6 +30,8 @@ substituting.
 
 10. Add null_subject and null_replacement modifiers to pcre2test.
 
+11. Add check for NULL subject to POSIX regexec() function.
+
 
 Version 10.39 29-October-2021
 -----------------------------
diff --git a/src/pcre2posix.c b/src/pcre2posix.c
index a5162df..647edcc 100644
--- a/src/pcre2posix.c
+++ b/src/pcre2posix.c
@@ -368,6 +368,8 @@ int rc, so, eo;
 int options = 0;
 pcre2_match_data *md = (pcre2_match_data *)preg->re_match_data;
 
+if (string == NULL) return REG_INVARG;
+
 if ((eflags & REG_NOTBOL) != 0) options |= PCRE2_NOTBOL;
 if ((eflags & REG_NOTEOL) != 0) options |= PCRE2_NOTEOL;
 if ((eflags & REG_NOTEMPTY) != 0) options |= PCRE2_NOTEMPTY;
diff --git a/src/pcre2test.c b/src/pcre2test.c
index 300c255..d5fde0d 100644
--- a/src/pcre2test.c
+++ b/src/pcre2test.c
@@ -771,7 +771,7 @@ static modstruct modlist[] = {
   PCRE2_NOTBOL|PCRE2_NOTEMPTY|PCRE2_NOTEOL)
 
 #define POSIX_SUPPORTED_MATCH_CONTROLS  (CTL_AFTERTEXT|CTL_ALLAFTERTEXT)
-#define POSIX_SUPPORTED_MATCH_CONTROLS2 (0)
+#define POSIX_SUPPORTED_MATCH_CONTROLS2 (CTL2_NULL_SUBJECT)
 
 /* Control bits that are not ignored with 'push'. */
 
@@ -4106,7 +4106,7 @@ Returns:      nothing
 static void
 show_controls(uint32_t controls, uint32_t controls2, const char *before)
 {
-fprintf(outfile, "%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s",
+fprintf(outfile, "%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s",
   before,
   ((controls & CTL_AFTERTEXT) != 0)? " aftertext" : "",
   ((controls & CTL_ALLAFTERTEXT) != 0)? " allaftertext" : "",
@@ -4136,6 +4136,8 @@ fprintf(outfile, "%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s
   ((controls & CTL_MEMORY) != 0)? " memory" : "",
   ((controls2 & CTL2_NL_SET) != 0)? " newline" : "",
   ((controls & CTL_NULLCONTEXT) != 0)? " null_context" : "",
+  ((controls2 & CTL2_NULL_REPLACEMENT) != 0)? " null_replacement" : "",
+  ((controls2 & CTL2_NULL_SUBJECT) != 0)? " null_subject" : "",
   ((controls & CTL_POSIX) != 0)? " posix" : "",
   ((controls & CTL_POSIX_NOSUB) != 0)? " posix_nosub" : "",
   ((controls & CTL_PUSH) != 0)? " push" : "",