diff --git a/standalone/regex.c b/standalone/regex.c
index 495a18eb97..acd46a1593 100644
--- a/standalone/regex.c
+++ b/standalone/regex.c
@@ -1,162 +1,242 @@
-/*
-* ModSecurity for Apache 2.x, http://www.modsecurity.org/
-* Copyright (c) 2004-2013 Trustwave Holdings, Inc. (http://www.trustwave.com/)
-*
-* You may not use this file except in compliance with
-* the License.  You may obtain a copy of the License at
-*
-*     http://www.apache.org/licenses/LICENSE-2.0
-*
-* If any of the files related to licensing are missing or if you have any
-* other questions related to licensing please contact Trustwave Holdings, Inc.
-* directly using the email address security@modsecurity.org.
-*/
-
-#include <limits.h>
-
-#include "http_core.h"
-#include "http_request.h"
-
-#include "modsecurity.h"
-#include "apache2.h"
-#include "http_main.h"
-#include "http_connection.h"
-
-#include "apr_optional.h"
-#include "mod_log_config.h"
-
-#include "msc_logging.h"
-#include "msc_util.h"
-
-#include "ap_mpm.h"
-#include "scoreboard.h"
-
-#include "apr_version.h"
-
-#include "apr_lib.h"
-#include "ap_config.h"
-#include "http_config.h"
-
-
-static apr_status_t regex_cleanup(void *preg)
-{
-    ap_regfree((ap_regex_t *) preg);
-    return APR_SUCCESS;
-}
-
-AP_DECLARE(ap_regex_t *) ap_pregcomp(apr_pool_t *p, const char *pattern,
-                                     int cflags)
-{
-    ap_regex_t *preg = apr_palloc(p, sizeof *preg);
-
-    if (ap_regcomp(preg, pattern, cflags)) {
-        return NULL;
-    }
-
-    apr_pool_cleanup_register(p, (void *) preg, regex_cleanup,
-                              apr_pool_cleanup_null);
-
-    return preg;
-}
-
-AP_DECLARE(void) ap_regfree(ap_regex_t *preg)
-{
-(pcre_free)(preg->re_pcre);
-}
-
-AP_DECLARE(int) ap_regcomp(ap_regex_t *preg, const char *pattern, int cflags)
-{
-const char *errorptr;
-int erroffset;
-int options = 0;
-int nsub = 0;
-
-if ((cflags & AP_REG_ICASE) != 0) options |= PCRE_CASELESS;
-if ((cflags & AP_REG_NEWLINE) != 0) options |= PCRE_MULTILINE;
-
-preg->re_pcre = pcre_compile(pattern, options, &errorptr, &erroffset, NULL);
-preg->re_erroffset = erroffset;
-
-if (preg->re_pcre == NULL) return AP_REG_INVARG;
-
-pcre_fullinfo((const pcre *)preg->re_pcre, NULL, PCRE_INFO_CAPTURECOUNT, &nsub);
-preg->re_nsub = nsub;
-return 0;
-}
-
-#ifndef POSIX_MALLOC_THRESHOLD
-#define POSIX_MALLOC_THRESHOLD (10)
-#endif
-
-AP_DECLARE(int) ap_regexec(const ap_regex_t *preg, const char *string,
-                           apr_size_t nmatch, ap_regmatch_t pmatch[],
-                           int eflags)
-{
-int rc;
-int options = 0;
-int *ovector = NULL;
-int small_ovector[POSIX_MALLOC_THRESHOLD * 3];
-int allocated_ovector = 0;
-
-if ((eflags & AP_REG_NOTBOL) != 0) options |= PCRE_NOTBOL;
-if ((eflags & AP_REG_NOTEOL) != 0) options |= PCRE_NOTEOL;
-
-((ap_regex_t *)preg)->re_erroffset = (apr_size_t)(-1);  /* Only has meaning after compile */
-
-if (nmatch > 0)
-  {
-  if (nmatch <= POSIX_MALLOC_THRESHOLD)
-    {
-    ovector = &(small_ovector[0]);
-    }
-  else
-    {
-    ovector = (int *)malloc(sizeof(int) * nmatch * 3);
-    if (ovector == NULL) return AP_REG_ESPACE;
-    allocated_ovector = 1;
-    }
-  }
-
-rc = pcre_exec((const pcre *)preg->re_pcre, NULL, string, (int)strlen(string),
-  0, options, ovector, nmatch * 3);
-
-if (rc == 0) rc = nmatch;    /* All captured slots were filled in */
-
-if (rc >= 0)
-  {
-  apr_size_t i;
-  for (i = 0; i < (apr_size_t)rc; i++)
-    {
-    pmatch[i].rm_so = ovector[i*2];
-    pmatch[i].rm_eo = ovector[i*2+1];
-    }
-  if (allocated_ovector) free(ovector);
-  for (; i < nmatch; i++) pmatch[i].rm_so = pmatch[i].rm_eo = -1;
-  return 0;
-  }
-
-else
-  {
-  if (allocated_ovector) free(ovector);
-  switch(rc)
-    {
-    case PCRE_ERROR_NOMATCH: return AP_REG_NOMATCH;
-    case PCRE_ERROR_NULL: return AP_REG_INVARG;
-    case PCRE_ERROR_BADOPTION: return AP_REG_INVARG;
-    case PCRE_ERROR_BADMAGIC: return AP_REG_INVARG;
-    case PCRE_ERROR_UNKNOWN_NODE: return AP_REG_ASSERT;
-    case PCRE_ERROR_NOMEMORY: return AP_REG_ESPACE;
-#ifdef PCRE_ERROR_MATCHLIMIT
-    case PCRE_ERROR_MATCHLIMIT: return AP_REG_ESPACE;
-#endif
-#ifdef PCRE_ERROR_BADUTF8
-    case PCRE_ERROR_BADUTF8: return AP_REG_INVARG;
-#endif
-#ifdef PCRE_ERROR_BADUTF8_OFFSET
-    case PCRE_ERROR_BADUTF8_OFFSET: return AP_REG_INVARG;
-#endif
-    default: return AP_REG_ASSERT;
-    }
-  }
-}
-
+/*
+* ModSecurity for Apache 2.x, http://www.modsecurity.org/
+* Copyright (c) 2004-2013 Trustwave Holdings, Inc. (http://www.trustwave.com/)
+*
+* You may not use this file except in compliance with
+* the License.  You may obtain a copy of the License at
+*
+*     http://www.apache.org/licenses/LICENSE-2.0
+*
+* If any of the files related to licensing are missing or if you have any
+* other questions related to licensing please contact Trustwave Holdings, Inc.
+* directly using the email address security@modsecurity.org.
+*/
+
+#include <limits.h>
+
+#include "http_core.h"
+#include "http_request.h"
+
+#include "modsecurity.h"
+#include "apache2.h"
+#include "http_main.h"
+#include "http_connection.h"
+
+#include "apr_optional.h"
+#include "mod_log_config.h"
+
+#include "msc_logging.h"
+#include "msc_util.h"
+
+#include "ap_mpm.h"
+#include "scoreboard.h"
+
+#include "apr_version.h"
+
+#include "apr_lib.h"
+#include "ap_config.h"
+#include "http_config.h"
+
+
+static apr_status_t regex_cleanup(void *preg)
+{
+    ap_regfree((ap_regex_t *) preg);
+    return APR_SUCCESS;
+}
+
+AP_DECLARE(ap_regex_t *) ap_pregcomp(apr_pool_t *p, const char *pattern,
+                                     int cflags)
+{
+    ap_regex_t *preg = apr_palloc(p, sizeof *preg);
+
+    if (ap_regcomp(preg, pattern, cflags)) {
+        return NULL;
+    }
+
+    apr_pool_cleanup_register(p, (void *) preg, regex_cleanup,
+                              apr_pool_cleanup_null);
+
+    return preg;
+}
+
+AP_DECLARE(void) ap_regfree(ap_regex_t *preg)
+{
+#ifdef WITH_PCRE2
+(pcre2_code_free)(preg->re_pcre);
+#else
+(pcre_free)(preg->re_pcre);
+#endif
+}
+
+AP_DECLARE(int) ap_regcomp(ap_regex_t *preg, const char *pattern, int cflags)
+{
+const char *errorptr;
+int erroffset;
+int options = 0;
+int nsub = 0;
+
+#ifdef WITH_PCRE2
+if ((cflags & AP_REG_ICASE) != 0) options |= PCRE2_CASELESS;
+if ((cflags & AP_REG_NEWLINE) != 0) options |= PCRE2_MULTILINE;
+int error_number = 0;
+PCRE2_SIZE error_offset = 0;
+PCRE2_SPTR pcre2_pattern = (PCRE2_SPTR)pattern;
+
+preg->re_pcre = pcre2_compile(pcre2_pattern, PCRE2_ZERO_TERMINATED,
+  options, &error_number, &error_offset, NULL);
+preg->re_erroffset = error_offset;
+
+if (preg->re_pcre == NULL) return AP_REG_INVARG;
+
+pcre2_pattern_info((const pcre2_code *)preg->re_pcre, PCRE2_INFO_CAPTURECOUNT, &nsub);
+preg->re_nsub = nsub;
+
+#else // otherwise use PCRE
+if ((cflags & AP_REG_ICASE) != 0) options |= PCRE_CASELESS;
+if ((cflags & AP_REG_NEWLINE) != 0) options |= PCRE_MULTILINE;
+
+preg->re_pcre = pcre_compile(pattern, options, &errorptr, &erroffset, NULL);
+preg->re_erroffset = erroffset;
+
+if (preg->re_pcre == NULL) return AP_REG_INVARG;
+
+pcre_fullinfo((const pcre *)preg->re_pcre, NULL, PCRE_INFO_CAPTURECOUNT, &nsub);
+preg->re_nsub = nsub;
+#endif  // end of WITH_PCRE
+return 0;
+}
+
+#ifndef POSIX_MALLOC_THRESHOLD
+#define POSIX_MALLOC_THRESHOLD (10)
+#endif
+
+AP_DECLARE(int) ap_regexec(const ap_regex_t *preg, const char *string,
+                           apr_size_t nmatch, ap_regmatch_t pmatch[],
+                           int eflags)
+{
+int rc;
+int options = 0;
+int *ovector = NULL;
+int small_ovector[POSIX_MALLOC_THRESHOLD * 3];
+int allocated_ovector = 0;
+
+#ifdef WITH_PCRE2
+if ((eflags & AP_REG_NOTBOL) != 0) options |= PCRE2_NOTBOL;
+if ((eflags & AP_REG_NOTEOL) != 0) options |= PCRE2_NOTEOL;
+#else
+if ((eflags & AP_REG_NOTBOL) != 0) options |= PCRE_NOTBOL;
+if ((eflags & AP_REG_NOTEOL) != 0) options |= PCRE_NOTEOL;
+#endif
+
+((ap_regex_t *)preg)->re_erroffset = (apr_size_t)(-1);  /* Only has meaning after compile */
+
+if (nmatch > 0)
+  {
+  if (nmatch <= POSIX_MALLOC_THRESHOLD)
+    {
+    ovector = &(small_ovector[0]);
+    }
+  else
+    {
+    ovector = (int *)malloc(sizeof(int) * nmatch * 3);
+    if (ovector == NULL) return AP_REG_ESPACE;
+    allocated_ovector = 1;
+    }
+  }
+
+#ifdef WITH_PCRE2
+{
+  PCRE2_SPTR pcre2_s;
+  int pcre2_ret;
+  pcre2_match_data *match_data;
+  PCRE2_SIZE *pcre2_ovector = NULL;
+
+  pcre2_s = (PCRE2_SPTR)string;
+  match_data = pcre2_match_data_create_from_pattern(preg->re_pcre, NULL);
+  pcre2_match_context *match_context = pcre2_match_context_create(NULL);
+
+  pcre2_ret = pcre2_match((const pcre2_code *)preg->re_pcre, pcre2_s, (int)strlen(string),
+      0, (uint32_t)options, match_data, match_context);
+
+  if (match_data != NULL) {
+      pcre2_ovector = pcre2_get_ovector_pointer(match_data);
+      if (pcre2_ovector != NULL) {
+          for (int i = 0; ((i < pcre2_ret) && ((i*2) <= nmatch * 3)); i++) {
+              if ((i*2) < nmatch * 3) {
+                  ovector[2*i] = pcre2_ovector[2*i];
+                  ovector[2*i+1] = pcre2_ovector[2*i+1];
+              }
+          }
+      }
+      pcre2_match_data_free(match_data);
+      pcre2_match_context_free(match_context);
+  }
+  /*
+    pcre2_match() returns one more than the highest numbered capturing pair
+    that has been set (for example, 1 if there are no captures) - see pcre2_match's manual
+  */
+  rc = pcre2_ret - 1;
+}
+#else
+rc = pcre_exec((const pcre *)preg->re_pcre, NULL, string, (int)strlen(string),
+  0, options, ovector, nmatch * 3);
+#endif
+
+if (rc == 0) rc = nmatch;    /* All captured slots were filled in */
+
+if (rc >= 0)
+  {
+  apr_size_t i;
+  for (i = 0; i < (apr_size_t)rc; i++)
+    {
+    pmatch[i].rm_so = ovector[i*2];
+    pmatch[i].rm_eo = ovector[i*2+1];
+    }
+  if (allocated_ovector) free(ovector);
+  for (; i < nmatch; i++) pmatch[i].rm_so = pmatch[i].rm_eo = -1;
+  return 0;
+  }
+
+else
+  {
+  if (allocated_ovector) free(ovector);
+  switch(rc)
+    {
+#ifdef WITH_PCRE2
+    case PCRE2_ERROR_NOMATCH: return AP_REG_NOMATCH;
+    case PCRE2_ERROR_NULL: return AP_REG_INVARG;
+    case PCRE2_ERROR_BADOPTION: return AP_REG_INVARG;
+    case PCRE2_ERROR_BADMAGIC: return AP_REG_INVARG;
+    // case PCRE2_ERROR_UNKNOWN_NODE: return AP_REG_ASSERT; not defined in PCRE2
+    case PCRE2_ERROR_NOMEMORY: return AP_REG_ESPACE;
+#ifdef PCRE2_ERROR_MATCHLIMIT
+    case PCRE2_ERROR_MATCHLIMIT: return AP_REG_ESPACE;
+#endif
+#ifdef PCRE2_ERROR_BADUTF8
+    case PCRE2_ERROR_BADUTF8: return AP_REG_INVARG;
+#endif
+#ifdef PCRE2_ERROR_BADUTF8_OFFSET
+    case PCRE2_ERROR_BADUTF8_OFFSET: return AP_REG_INVARG;
+#endif
+#else // with old PCRE
+    case PCRE_ERROR_NOMATCH: return AP_REG_NOMATCH;
+    case PCRE_ERROR_NULL: return AP_REG_INVARG;
+    case PCRE_ERROR_BADOPTION: return AP_REG_INVARG;
+    case PCRE_ERROR_BADMAGIC: return AP_REG_INVARG;
+    case PCRE_ERROR_UNKNOWN_NODE: return AP_REG_ASSERT;
+    case PCRE_ERROR_NOMEMORY: return AP_REG_ESPACE;
+#ifdef PCRE_ERROR_MATCHLIMIT
+    case PCRE_ERROR_MATCHLIMIT: return AP_REG_ESPACE;
+#endif
+#ifdef PCRE_ERROR_BADUTF8
+    case PCRE_ERROR_BADUTF8: return AP_REG_INVARG;
+#endif
+#ifdef PCRE_ERROR_BADUTF8_OFFSET
+    case PCRE_ERROR_BADUTF8_OFFSET: return AP_REG_INVARG;
+#endif
+#endif // end of WITH_PCRE
+    default: return AP_REG_ASSERT;
+    }
+  }
+}
+