From d965985a5219ed5dbe09fc83177beb5bb56f73fd Mon Sep 17 00:00:00 2001
From: Jakob Kramer <jakob.kramer@gmx.de>
Date: Sat, 3 May 2014 20:24:08 +0200
Subject: [PATCH] sort: add -b flag; don't use it as default

---
 sort.c | 33 +++++++++++++++++++++++++++------
 1 file changed, 27 insertions(+), 6 deletions(-)

diff --git a/sort.c b/sort.c
index 63b9509..5af81d2 100644
--- a/sort.c
+++ b/sort.c
@@ -30,11 +30,13 @@ static char *next_nonblank(char *);
 static char *next_blank(char *);
 static int parse_keydef(struct keydef *, char *);
 static char *skip_columns(char *, size_t);
+static char *end_column(char *);
 static char *columns(char *, const struct keydef *);
 
 static bool rflag = false;
 static bool uflag = false;
 static bool nflag = false;
+static bool bflag = false;
 
 static void
 usage(void)
@@ -59,6 +61,9 @@ main(int argc, char *argv[])
 	case 'u':
 		uflag = true;
 		break;
+	case 'b':
+		bflag = true;
+		break;
 	case 'k':
 		addkeydef(EARGF(usage()));
 		break;
@@ -169,7 +174,7 @@ parse_keydef(struct keydef *kd, char *s)
 		kd->start_char = strtoul(rest+1, &rest, 10);
 	if(*rest == ',') {
 		kd->end_column = strtoul(rest+1, &rest, 10);
-		if(kd->end_column < kd->start_column)
+		if(kd->end_column && kd->end_column < kd->start_column)
 			enprintf(2, ",%u is too small\n", kd->end_column);
 		if(*rest == '.')
 			kd->end_char = strtoul(rest+1, &rest, 10);
@@ -201,14 +206,30 @@ skip_columns(char *s, size_t n)
 	size_t i;
 
 	for(i = 0; i < n; i++) {
-		if(i != 0)
+		if(bflag) {
+			if(i != 0)
+				s = next_blank(s);
+			s = next_nonblank(s);
+		} else {
+			if(i == 0)
+				continue;
+			s = next_nonblank(s);
 			s = next_blank(s);
-		s = next_nonblank(s);
+		}
 	}
 
 	return s;
 }
 
+static char *
+end_column(char *s)
+{
+	if(bflag)
+		return next_blank(s);
+	else
+		return next_blank(next_nonblank(s));
+}
+
 static char *
 columns(char *line, const struct keydef *kd)
 {
@@ -216,14 +237,14 @@ columns(char *line, const struct keydef *kd)
 	char *res;
 
 	start = skip_columns(line, kd->start_column);
-	start += MIN(kd->start_char, next_blank(start) - start) - 1;
+	start += MIN(kd->start_char, end_column(start) - start) - 1;
 
 	if(kd->end_column) {
 		end = skip_columns(line, kd->end_column);
 		if(kd->end_char)
-			end += MIN(kd->end_char, next_blank(end) - end);
+			end += MIN(kd->end_char, end_column(end) - end);
 		else
-			end = next_blank(end);
+			end = end_column(end);
 	} else {
 		end = line + strlen(line);
 	}