git-rev-list: Add regexp tuning options

This patch introduces --extended-regexp and --regexp-ignore-case options to
tune what kind of patterns the pattern-limiting options (--grep, --author,
...) accept.

Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Documentation/git-rev-list.txt

@@ -25,6 +25,7 @@ SYNOPSIS
 	     [ \--cherry-pick ]
 	     [ \--encoding[=<encoding>] ]
 	     [ \--(author|committer|grep)=<pattern> ]
+	     [ \--regexp-ignore-case ] [ \--extended-regexp ]
 	     [ \--date={local|relative|default} ]
 	     [ [\--objects | \--objects-edge] [ \--unpacked ] ]
 	     [ \--pretty | \--header ]
@@ -214,6 +215,15 @@ limiting may be applied.
 	Limit the commits output to ones with log message that
 	matches the specified pattern (regular expression).
 
+--regexp-ignore-case::
+
+	Match the regexp limiting patterns without regard to letters case.
+
+--extended-regexp::
+
+	Consider the limiting patterns to be extended regular expressions
+	instead of the default basic regular expressions.
+
 --remove-empty::
 
 	Stop when a given path disappears from the tree.

revision.c

@@ -881,6 +881,7 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
 	const char **unrecognized = argv + 1;
 	int left = 1;
 	int all_match = 0;
+	int regflags = 0;
 
 	/* First, search for "--" */
 	seen_dashdash = 0;
@@ -1152,6 +1153,14 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
 				add_message_grep(revs, arg+7);
 				continue;
 			}
+			if (!prefixcmp(arg, "--extended-regexp")) {
+				regflags |= REG_EXTENDED;
+				continue;
+			}
+			if (!prefixcmp(arg, "--regexp-ignore-case")) {
+				regflags |= REG_ICASE;
+				continue;
+			}
 			if (!strcmp(arg, "--all-match")) {
 				all_match = 1;
 				continue;
@@ -1200,6 +1209,9 @@ int setup_revisions(int argc, const char **argv, struct rev_info *revs, const ch
 		}
 	}
 
+	if (revs->grep_filter)
+		revs->grep_filter->regflags |= regflags;
+
 	if (show_merge)
 		prepare_show_merge(revs);
 	if (def && !revs->pending.nr) {