[PATCH] git-pickaxe: -L /regexp/,/regexp/

@@ -17,6 +17,7 @@
 
 #include <time.h>
 #include <sys/time.h>
+#include <regex.h>
 
 static char pickaxe_usage[] =
 "git-pickaxe [-c] [-l] [-t] [-f] [-n] [-p] [-L n,m] [-S <revs-file>] [-M] [-C] [-C] [commit] [--] file\n"

@@ -1533,6 +1534,85 @@ static const char *add_prefix(const char
 	return prefix_path(prefix, strlen(prefix), path);
 }
 
+static const char *parse_loc(const char *spec,
+			     struct scoreboard *sb, long lno,
+			     long begin, long *ret)
+{
+	char *term;
+	const char *line;
+	long num;
+	regex_t regexp;
+
+	num = strtol(spec, &term, 10);
+	if (term != spec) {
+		*ret = num;
+		return term;
+	}
+
+	if (spec[0] != '/')
+		return spec;
+
+	/* it could be a regexp of form /.../ */
+	for (term = (char*) spec + 1; *term && *term != '/'; term++) {
+		if (*term == '\\')
+			term++;
+	}
+	if (*term != '/')
+		return spec;
+	/* try [spec+1 .. term-1] as regexp */
+	*term = 0;
+	if (regcomp(&regexp, spec + 1, REG_NEWLINE)) {
+		/* not a regexp */
+	error_return:
+		regfree(&regexp);
+		*term = '/';
+		return spec;
+	}
+
+	/* Now find the first line that matches the regexp, after
+	 * line "begin" in sb->final_buf.
+	 */
+	while (begin < lno) {
+		char *nline;
+		int hit;
+
+		begin++;
+		line = nth_line(sb, begin);
+		if (begin < lno) {
+			nline = (char*) nth_line(sb, begin+1);
+			nline[-1] = 0;
+		}
+		hit = regexec(&regexp, line, 0, NULL, 0);
+		if (begin < lno)
+			nline[-1] = '\n';
+		if (!hit) {
+			/* lines count from 1 in UI terms */
+			*ret = begin + 1;
+			regfree(&regexp);
+			*term++ = '/';
+			return term;
+		}
+	}
+	goto error_return;
+}
+
+static void prepare_blame_range(struct scoreboard *sb,
+				const char *bottomtop,
+				long lno,
+				long *bottom, long *top)
+{
+	const char *term;
+
+	term = parse_loc(bottomtop, sb, lno, 0, bottom);
+	if (*term == ',') {
+		term = parse_loc(term + 1, sb, lno, *bottom + 1, top);
+		if (*term)
+			usage(pickaxe_usage);
+	}
+	if (*term)
+		usage(pickaxe_usage);
+}
+
 int cmd_pickaxe(int argc, const char **argv, const char *prefix)
 {
 	struct rev_info revs;

@@ -1547,11 +1627,11 @@ int cmd_pickaxe(int argc, const char **a
 	const char *revs_file = NULL;
 	const char *final_commit_name = NULL;
 	char type[10];
+	const char *bottomtop = NULL;
 
 	save_commit_buffer = 0;
 
 	opt = 0;
-	bottom = top = 0;
 	seen_dashdash = 0;
 	for (unk = i = 1; i < argc; i++) {
 		const char *arg = argv[i];

@@ -1578,7 +1658,6 @@ int cmd_pickaxe(int argc, const char **a
 			blame_copy_score = parse_score(arg+2);
 		}
 		else if (!strncmp("-L", arg, 2)) {
-			char *term;
 			if (!arg[2]) {
 				if (++i >= argc)
 					usage(pickaxe_usage);

@@ -1586,18 +1665,9 @@ int cmd_pickaxe(int argc, const char **a
 			}
 			else
 				arg += 2;
-			if (bottom || top)
+			if (bottomtop)
 				die("More than one '-L n,m' option given");
-			bottom = strtol(arg, &term, 10);
-			if (*term == ',') {
-				top = strtol(term + 1, &term, 10);
-				if (*term)
-					usage(pickaxe_usage);
-			}
-			if (bottom && top && top < bottom) {
-				unsigned long tmp;
-				tmp = top; top = bottom; bottom = tmp;
-			}
+			bottomtop = arg;
 		}
 		else if (!strcmp("--score-debug", arg))
 			output_option |= OUTPUT_SHOW_SCORE;

@@ -1758,6 +1828,13 @@ int cmd_pickaxe(int argc, const char **a
 	num_read_blob++;
 	lno = prepare_lines(&sb);
 
+	bottom = top = 0;
+	if (bottomtop)
+		prepare_blame_range(&sb, bottomtop, lno, &bottom, &top);
+	if (bottom && top && top < bottom) {
+		long tmp;
+		tmp = top; top = bottom; bottom = tmp;
+	}
 	if (bottom < 1)
 		bottom = 1;
 	if (top < 1)