grep: rewrite an if/else condition to avoid duplicate expression

diff --git a/grep.c b/grep.c
index 7b2b96a4376efe51e41f9311c6fa5250a2dcd13d..6325cafe73fe695d5bb04bc979d79917669255f4 100644 (file)
--- a/grep.c
+++ b/grep.c
@@ -4,6 +4,8 @@
 #include "xdiff-interface.h"
 #include "diff.h"
 #include "diffcore.h"
+#include "commit.h"
+#include "quote.h"
 
 static int grep_source_load(struct grep_source *gs);
 static int grep_source_is_binary(struct grep_source *gs);
@@ -396,15 +398,52 @@ static int is_fixed(const char *s, size_t len)
        return 1;
 }
 
+static void compile_fixed_regexp(struct grep_pat *p, struct grep_opt *opt)
+{
+       struct strbuf sb = STRBUF_INIT;
+       int err;
+       int regflags;
+
+       basic_regex_quote_buf(&sb, p->pattern);
+       regflags = opt->regflags & ~REG_EXTENDED;
+       if (opt->ignore_case)
+               regflags |= REG_ICASE;
+       err = regcomp(&p->regexp, sb.buf, regflags);
+       if (opt->debug)
+               fprintf(stderr, "fixed %s\n", sb.buf);
+       strbuf_release(&sb);
+       if (err) {
+               char errbuf[1024];
+               regerror(err, &p->regexp, errbuf, sizeof(errbuf));
+               regfree(&p->regexp);
+               compile_regexp_failed(p, errbuf);
+       }
+}
+
 static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
 {
+       int icase, ascii_only;
        int err;
 
        p->word_regexp = opt->word_regexp;
        p->ignore_case = opt->ignore_case;
+       icase          = opt->regflags & REG_ICASE || p->ignore_case;
+       ascii_only     = !has_non_ascii(p->pattern);
 
+       /*
+        * Even when -F (fixed) asks us to do a non-regexp search, we
+        * may not be able to correctly case-fold when -i
+        * (ignore-case) is asked (in which case, we'll synthesize a
+        * regexp to match the pattern that matches regexp special
+        * characters literally, while ignoring case differences).  On
+        * the other hand, even without -F, if the pattern does not
+        * have any regexp special characters and there is no need for
+        * case-folding search, we can internally turn it into a
+        * simple string match using kws.  p->fixed tells us if we
+        * want to use kws.
+        */
        if (opt->fixed || is_fixed(p->pattern, p->patternlen))
-               p->fixed = 1;
+               p->fixed = !icase || ascii_only;
        else
                p->fixed = 0;
 
@@ -416,6 +455,14 @@ static void compile_regexp(struct grep_pat *p, struct grep_opt *opt)
                kwsincr(p->kws, p->pattern, p->patternlen);
                kwsprep(p->kws);
                return;
+       } else if (opt->fixed) {
+               /*
+                * We come here when the pattern has the non-ascii
+                * characters we cannot case-fold, and asked to
+                * ignore-case.
+                */
+               compile_fixed_regexp(p, opt);
+               return;
        }
 
        if (opt->pcre) {