# HG changeset patch
# User Maxim Dounin <mdounin@mdounin.ru>
# Date 1640383636 -10800
# Node ID fbbb5ce5299597fcf7bb502d871a65c75cdb86b5
# Parent  0b5f12d5c531be630a4aae644686be83cfed3267
PCRE2 and PCRE binary compatibility.

With this change, dynamic modules using nginx regex interface can be used
regardless of the variant of the PCRE library nginx was compiled with.

If a module is compiled with different PCRE library variant, in case of
ngx_regex_exec() errors it will report wrong function name in error
messages.  This is believed to be tolerable, given that fixing this will
require interface changes.

diff --git a/src/core/ngx_regex.c b/src/core/ngx_regex.c
--- a/src/core/ngx_regex.c
+++ b/src/core/ngx_regex.c
@@ -118,6 +118,7 @@ ngx_regex_compile(ngx_regex_compile_t *r
     char                   *p;
     u_char                  errstr[128];
     size_t                  erroff;
+    uint32_t                options;
     pcre2_code             *re;
     ngx_regex_elt_t        *elt;
     pcre2_general_context  *gctx;
@@ -152,11 +153,24 @@ ngx_regex_compile(ngx_regex_compile_t *r
         ngx_regex_malloc_done();
     }
 
+    options = 0;
+
+    if (rc->options & NGX_REGEX_CASELESS) {
+        options |= PCRE2_CASELESS;
+    }
+
+    if (rc->options & ~NGX_REGEX_CASELESS) {
+        rc->err.len = ngx_snprintf(rc->err.data, rc->err.len,
+                            "regex \"%V\" compilation failed: invalid options",
+                            &rc->pattern)
+                      - rc->err.data;
+        return NGX_ERROR;
+    }
+
     ngx_regex_malloc_init(rc->pool);
 
-    re = pcre2_compile(rc->pattern.data, rc->pattern.len,
-                       (uint32_t) rc->options, &errcode, &erroff,
-                       ngx_regex_compile_context);
+    re = pcre2_compile(rc->pattern.data, rc->pattern.len, options,
+                       &errcode, &erroff, ngx_regex_compile_context);
 
     /* ensure that there is no current pool */
     ngx_regex_malloc_done();
@@ -252,11 +266,26 @@ ngx_regex_compile(ngx_regex_compile_t *r
     char             *p;
     pcre             *re;
     const char       *errstr;
+    ngx_uint_t        options;
     ngx_regex_elt_t  *elt;
 
+    options = 0;
+
+    if (rc->options & NGX_REGEX_CASELESS) {
+        options |= PCRE_CASELESS;
+    }
+
+    if (rc->options & ~NGX_REGEX_CASELESS) {
+        rc->err.len = ngx_snprintf(rc->err.data, rc->err.len,
+                            "regex \"%V\" compilation failed: invalid options",
+                            &rc->pattern)
+                      - rc->err.data;
+        return NGX_ERROR;
+    }
+
     ngx_regex_malloc_init(rc->pool);
 
-    re = pcre_compile((const char *) rc->pattern.data, (int) rc->options,
+    re = pcre_compile((const char *) rc->pattern.data, (int) options,
                       &errstr, &erroff, NULL);
 
     /* ensure that there is no current pool */
@@ -413,6 +442,15 @@ failed:
     return rc;
 }
 
+#else
+
+ngx_int_t
+ngx_regex_exec(ngx_regex_t *re, ngx_str_t *s, int *captures, ngx_uint_t size)
+{
+    return pcre_exec(re->code, re->extra, (const char *) s->data, s->len,
+                     0, 0, captures, size);
+}
+
 #endif
 
 
diff --git a/src/core/ngx_regex.h b/src/core/ngx_regex.h
--- a/src/core/ngx_regex.h
+++ b/src/core/ngx_regex.h
@@ -19,7 +19,6 @@
 #include <pcre2.h>
 
 #define NGX_REGEX_NO_MATCHED   PCRE2_ERROR_NOMATCH   /* -1 */
-#define NGX_REGEX_CASELESS     PCRE2_CASELESS
 
 typedef pcre2_code  ngx_regex_t;
 
@@ -28,7 +27,6 @@ typedef pcre2_code  ngx_regex_t;
 #include <pcre.h>
 
 #define NGX_REGEX_NO_MATCHED   PCRE_ERROR_NOMATCH    /* -1 */
-#define NGX_REGEX_CASELESS     PCRE_CASELESS
 
 typedef struct {
     pcre        *code;
@@ -38,10 +36,13 @@ typedef struct {
 #endif
 
 
+#define NGX_REGEX_CASELESS     0x00000001
+
+
 typedef struct {
     ngx_str_t     pattern;
     ngx_pool_t   *pool;
-    ngx_int_t     options;
+    ngx_uint_t    options;
 
     ngx_regex_t  *regex;
     int           captures;
@@ -61,19 +62,13 @@ typedef struct {
 void ngx_regex_init(void);
 ngx_int_t ngx_regex_compile(ngx_regex_compile_t *rc);
 
-#if (NGX_PCRE2)
-
 ngx_int_t ngx_regex_exec(ngx_regex_t *re, ngx_str_t *s, int *captures,
     ngx_uint_t size);
+
+#if (NGX_PCRE2)
 #define ngx_regex_exec_n       "pcre2_match()"
-
 #else
-
-#define ngx_regex_exec(re, s, captures, size)                                \
-    pcre_exec(re->code, re->extra, (const char *) (s)->data, (s)->len, 0, 0, \
-              captures, size)
 #define ngx_regex_exec_n       "pcre_exec()"
-
 #endif
 
 ngx_int_t ngx_regex_exec_array(ngx_array_t *a, ngx_str_t *s, ngx_log_t *log);