more PHP 7 compatibility and license clarification

4 files changed, 162 insertions, 8 deletions

diff --git a/PHP_LICENSE b/PHP_LICENSE
new file mode 100644
index 0000000..4076fe9
--- /dev/null
+++ b/PHP_LICENSE
@@ -0,0 +1,68 @@
+--------------------------------------------------------------------
+                  The PHP License, version 3.01
+Copyright (c) 1999 - 2019 The PHP Group. All rights reserved.
+--------------------------------------------------------------------
+
+Redistribution and use in source and binary forms, with or without
+modification, is permitted provided that the following conditions
+are met:
+
+  1. Redistributions of source code must retain the above copyright
+     notice, this list of conditions and the following disclaimer.
+
+  2. Redistributions in binary form must reproduce the above copyright
+     notice, this list of conditions and the following disclaimer in
+     the documentation and/or other materials provided with the
+     distribution.
+
+  3. The name "PHP" must not be used to endorse or promote products
+     derived from this software without prior written permission. For
+     written permission, please contact group@php.net.
+
+  4. Products derived from this software may not be called "PHP", nor
+     may "PHP" appear in their name, without prior written permission
+     from group@php.net.  You may indicate that your software works in
+     conjunction with PHP by saying "Foo for PHP" instead of calling
+     it "PHP Foo" or "phpfoo"
+
+  5. The PHP Group may publish revised and/or new versions of the
+     license from time to time. Each version will be given a
+     distinguishing version number.
+     Once covered code has been published under a particular version
+     of the license, you may always continue to use it under the terms
+     of that version. You may also choose to use such covered code
+     under the terms of any subsequent version of the license
+     published by the PHP Group. No one other than the PHP Group has
+     the right to modify the terms applicable to covered code created
+     under this License.
+
+  6. Redistributions of any form whatsoever must retain the following
+     acknowledgment:
+     "This product includes PHP software, freely available from
+     <http://www.php.net/software/>".
+
+THIS SOFTWARE IS PROVIDED BY THE PHP DEVELOPMENT TEAM ``AS IS'' AND
+ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE PHP
+DEVELOPMENT TEAM OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+OF THE POSSIBILITY OF SUCH DAMAGE.
+
+--------------------------------------------------------------------
+
+This software consists of voluntary contributions made by many
+individuals on behalf of the PHP Group.
+
+The PHP Group can be contacted via Email at group@php.net.
+
+For more information on the PHP Group and the PHP project,
+please see <http://www.php.net>.
+
+PHP includes the Zend Engine, freely available at
+<http://www.zend.com>.
diff --git a/doc/source/faq.rst b/doc/source/faq.rst
index bdfc7c1..57b910d 100644
--- a/doc/source/faq.rst
+++ b/doc/source/faq.rst
@@ -79,6 +79,12 @@ We chose the LGPL because we don't care that much how you're using Snuffleupagus
 but we'd like to force people to make their improvements/contributions
 available to everyone.
 
+The complete license text is shipped with the sources and can be found under ``LICENSE``.
+
+For compatibility with older PHP versions, some original PHP source code was copied or ported back to older versions.
+This source code resides in ``src/sp_php_compat.c`` and ``src/sp_php_compat.h`` and retains its original license
+`The PHP License, version 3.01 <https://www.php.net/license/3_01.txt>`, also included with the sources as ``PHP_LICENSE``.
+
 
 What is the different between SNuffleupaugs and a (WAF) like ModSecurity?
 """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
diff --git a/src/sp_php_compat.c b/src/sp_php_compat.c
index 933acd8..cd7c3e7 100644
--- a/src/sp_php_compat.c
+++ b/src/sp_php_compat.c
@@ -2,8 +2,7 @@
 
 #if PHP_VERSION_ID < 80000
 
-// zend_string_concat2 taken from PHP 8.0.9 zend_string.c
-// TODO: license clarification
+// copied from PHP 8.0.9 sources
 
 ZEND_API zend_string *zend_string_concat2(
                 const char *str1, size_t str1_len,
diff --git a/src/sp_php_compat.h b/src/sp_php_compat.h
index 380abe4..992c3e2 100644
--- a/src/sp_php_compat.h
+++ b/src/sp_php_compat.h
@@ -1,12 +1,93 @@
 #if PHP_VERSION_ID < 80000
+
+// copied from PHP 8.0.9 sources
 ZEND_API zend_string *zend_string_concat2(
-    const char *str1, size_t str1_len,
-    const char *str2, size_t str2_len);
+        const char *str1, size_t str1_len,
+        const char *str2, size_t str2_len);
 
 #define ZEND_HASH_REVERSE_FOREACH_KEY_PTR(ht, _h, _key, _ptr) \
-    ZEND_HASH_REVERSE_FOREACH(ht, 0); \
-    _h = _p->h; \
-    _key = _p->key; \
-    _ptr = Z_PTR_P(_z);
+        ZEND_HASH_REVERSE_FOREACH(ht, 0); \
+        _h = _p->h; \
+        _key = _p->key; \
+        _ptr = Z_PTR_P(_z);
+
+#endif
+
+#if PHP_VERSION_ID < 70300
+
+// copied from PHP 7.4.22 sources
+
+static zend_always_inline uint32_t zend_gc_delref(zend_refcounted_h *p) {
+        ZEND_ASSERT(p->refcount > 0);
+        // ZEND_RC_MOD_CHECK(p);
+        return --(p->refcount);
+}
+#define GC_DELREF(p)                            zend_gc_delref(&(p)->gc)
+
+static zend_always_inline void zend_string_release_ex(zend_string *s, int persistent)
+{
+        if (!ZSTR_IS_INTERNED(s)) {
+                if (GC_DELREF(s) == 0) {
+                        if (persistent) {
+                                ZEND_ASSERT(GC_FLAGS(s) & IS_STR_PERSISTENT);
+                                free(s);
+                        } else {
+                                ZEND_ASSERT(!(GC_FLAGS(s) & IS_STR_PERSISTENT));
+                                efree(s);
+                        }
+                }
+        }
+}
+
+static zend_always_inline void zend_string_efree(zend_string *s)
+{
+        ZEND_ASSERT(!ZSTR_IS_INTERNED(s));
+        ZEND_ASSERT(GC_REFCOUNT(s) <= 1);
+        ZEND_ASSERT(!(GC_FLAGS(s) & IS_STR_PERSISTENT));
+        efree(s);
+}
+
+#endif
+
+#if PHP_VERSION_ID < 70200
+
+#undef ZEND_HASH_REVERSE_FOREACH
+
+// copied from PHP 7.4.22 sources
+
+#define ZEND_HASH_REVERSE_FOREACH(_ht, indirect) do { \
+        HashTable *__ht = (_ht); \
+        uint32_t _idx = __ht->nNumUsed; \
+        Bucket *_p = __ht->arData + _idx; \
+        zval *_z; \
+        for (_idx = __ht->nNumUsed; _idx > 0; _idx--) { \
+                _p--; \
+                _z = &_p->val; \
+                if (indirect && Z_TYPE_P(_z) == IS_INDIRECT) { \
+                        _z = Z_INDIRECT_P(_z); \
+                } \
+                if (UNEXPECTED(Z_TYPE_P(_z) == IS_UNDEF)) continue;
+
+
+#define ZEND_HASH_FOREACH_END_DEL() \
+                        __ht->nNumOfElements--; \
+                        do { \
+                                uint32_t j = HT_IDX_TO_HASH(_idx - 1); \
+                                uint32_t nIndex = _p->h | __ht->nTableMask; \
+                                uint32_t i = HT_HASH(__ht, nIndex); \
+                                if (UNEXPECTED(j != i)) { \
+                                        Bucket *prev = HT_HASH_TO_BUCKET(__ht, i); \
+                                        while (Z_NEXT(prev->val) != j) { \
+                                                i = Z_NEXT(prev->val); \
+                                                prev = HT_HASH_TO_BUCKET(__ht, i); \
+                                        } \
+                                        Z_NEXT(prev->val) = Z_NEXT(_p->val); \
+                                } else { \
+                                        HT_HASH(__ht, nIndex) = Z_NEXT(_p->val); \
+                                } \
+                        } while (0); \
+                } \
+                __ht->nNumUsed = _idx; \
+        } while (0)
 
 #endif
\ No newline at end of file