+struct regex_quote_spec
+regex_quote_spec_posix (int cflags, bool anchored)
+{
+ struct regex_quote_spec result;
+
+ strcpy (result.special, cflags != 0 ? ere_special : bre_special);
+ result.multibyte = true;
+ result.anchored = anchored;
+
+ return result;
+}
+
+/* Syntax bit values, defined in GNU <regex.h>. We don't include it here,
+ otherwise this module would need to depend on gnulib module 'regex'. */
+#define RE_BK_PLUS_QM 0x00000002
+#define RE_INTERVALS 0x00000200
+#define RE_LIMITED_OPS 0x00000400
+#define RE_NEWLINE_ALT 0x00000800
+#define RE_NO_BK_BRACES 0x00001000
+#define RE_NO_BK_PARENS 0x00002000
+#define RE_NO_BK_VBAR 0x00008000
+
+struct regex_quote_spec
+regex_quote_spec_gnu (unsigned long /*reg_syntax_t*/ syntax, bool anchored)
+{
+ struct regex_quote_spec result;
+ char *p;
+
+ p = result.special;
+ memcpy (p, bre_special, sizeof (bre_special) - 1);
+ p += sizeof (bre_special) - 1;
+ if ((syntax & RE_LIMITED_OPS) == 0 && (syntax & RE_BK_PLUS_QM) == 0)
+ {
+ *p++ = '+';
+ *p++ = '?';
+ }
+ if ((syntax & RE_INTERVALS) != 0 && (syntax & RE_NO_BK_BRACES) != 0)
+ {
+ *p++ = '{';
+ *p++ = '}';
+ }
+ if ((syntax & RE_NO_BK_PARENS) != 0)
+ {
+ *p++ = '(';
+ *p++ = ')';
+ }
+ if ((syntax & RE_LIMITED_OPS) == 0 && (syntax & RE_NO_BK_VBAR) != 0)
+ *p++ = '|';
+ if ((syntax & RE_NEWLINE_ALT) != 0)
+ *p++ = '\n';
+ *p = '\0';
+
+ result.multibyte = true;
+ result.anchored = anchored;
+
+ return result;
+}
+
+/* Characters that are special in a PCRE. */
+static const char pcre_special[] = "$^.*[]\\+?{}()|";
+
+/* Options bit values, defined in <pcre.h>. We don't include it here, because
+ it is not a standard header. */
+#define PCRE_ANCHORED 0x00000010
+#define PCRE_EXTENDED 0x00000008
+
+struct regex_quote_spec
+regex_quote_spec_pcre (int options, bool anchored)
+{
+ struct regex_quote_spec result;
+ char *p;
+
+ p = result.special;
+ memcpy (p, bre_special, sizeof (pcre_special) - 1);
+ p += sizeof (pcre_special) - 1;
+ if (options & PCRE_EXTENDED)
+ {
+ *p++ = ' ';
+ *p++ = '\t';
+ *p++ = '\n';
+ *p++ = '\v';
+ *p++ = '\f';
+ *p++ = '\r';
+ *p++ = '#';
+ }
+ *p = '\0';
+
+ /* PCRE regular expressions consist of UTF-8 characters of options contains
+ PCRE_UTF8 and of single bytes otherwise. */
+ result.multibyte = false;
+ /* If options contains PCRE_ANCHORED, the anchoring is implicit. */
+ result.anchored = (options & PCRE_ANCHORED ? 0 : anchored);
+
+ return result;
+}
+