Router: matching regular expressions support.

src/nxt_pcre.c

@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) Axel Duch
+ * Copyright (C) NGINX, Inc.
+ */
+
+#include <nxt_main.h>
+#include <nxt_regex.h>
+#include <pcre.h>
+
+
+struct nxt_regex_s {
+    pcre        *code;
+    pcre_extra  *extra;
+    nxt_str_t   pattern;
+};
+
+struct nxt_regex_match_s {
+    int  ovecsize;
+    int  ovec[];
+};
+
+
+static void *nxt_pcre_malloc(size_t size);
+static void nxt_pcre_free(void *p);
+
+static nxt_mp_t  *nxt_pcre_mp;
+
+
+nxt_regex_t *
+nxt_regex_compile(nxt_mp_t *mp, nxt_str_t *source, nxt_regex_err_t *err)
+{
+    int          erroffset;
+    char         *pattern;
+    void         *saved_malloc, *saved_free;
+    nxt_regex_t  *re;
+
+    err->offset = source->length;
+
+    re = nxt_mp_get(mp, sizeof(nxt_regex_t) + source->length + 1);
+    if (nxt_slow_path(re == NULL)) {
+        err->msg = "memory allocation failed";
+        return NULL;
+    }
+
+    pattern = nxt_pointer_to(re, sizeof(nxt_regex_t));
+
+    nxt_memcpy(pattern, source->start, source->length);
+    pattern[source->length] = '\0';
+
+    re->pattern.length = source->length;
+    re->pattern.start = (u_char *) pattern;
+
+    saved_malloc = pcre_malloc;
+    saved_free = pcre_free;
+
+    pcre_malloc = nxt_pcre_malloc;
+    pcre_free = nxt_pcre_free;
+    nxt_pcre_mp = mp;
+
+    re->code = pcre_compile(pattern, 0, &err->msg, &erroffset, NULL);
+    if (nxt_fast_path(re->code != NULL)) {
+#if 0
+        re->extra = pcre_study(re->code, PCRE_STUDY_JIT_COMPILE, &err->msg);
+        if (nxt_slow_path(re->extra == NULL && err->msg != NULL)) {
+            nxt_log_warn(thr->log, "pcre_study(%V) failed: %s", source, err->msg);
+        }
+#else
+        re->extra = NULL;
+#endif
+
+    } else {
+        err->offset = erroffset;
+        re = NULL;
+    }
+
+    pcre_malloc = saved_malloc;
+    pcre_free = saved_free;
+
+    return re;
+}
+
+
+static void*
+nxt_pcre_malloc(size_t size)
+{
+    if (nxt_slow_path(nxt_pcre_mp == NULL)) {
+        nxt_thread_log_alert("pcre_malloc(%uz) called without memory pool",
+                             size);
+        return NULL;
+    }
+
+    nxt_thread_log_debug("pcre_malloc(%uz), pool %p", size, nxt_pcre_mp);
+
+    return nxt_mp_get(nxt_pcre_mp, size);
+}
+
+
+static void
+nxt_pcre_free(void *p)
+{
+}
+
+
+nxt_regex_match_t *
+nxt_regex_match_create(nxt_mp_t *mp, size_t size)
+{
+    nxt_regex_match_t  *match;
+
+    match = nxt_mp_get(mp, sizeof(nxt_regex_match_t) + sizeof(int) * size);
+    if (nxt_fast_path(match != NULL)) {
+        match->ovecsize = size;
+    }
+
+    return match;
+}
+
+
+nxt_int_t
+nxt_regex_match(nxt_regex_t *re, u_char *subject, size_t length,
+    nxt_regex_match_t *match)
+{
+    int  ret;
+
+    ret = pcre_exec(re->code, re->extra, (const char *) subject, length, 0, 0,
+                    match->ovec, match->ovecsize);
+    if (nxt_slow_path(ret < PCRE_ERROR_NOMATCH)) {
+        nxt_thread_log_error(NXT_LOG_ERR,
+                             "pcre_exec() failed: %d on \"%*s\" using \"%V\"",
+                             ret, length, subject, &re->pattern);
+
+        return NXT_ERROR;
+    }
+
+    return (ret != PCRE_ERROR_NOMATCH);
+}