[PATCH] ls: make -C exclusive with -l and -1 (bug 2959).

[James Youngman]

Also explain why we cannot do this right now for -c and -u (and that
means this change does not fully fix bug 2959).

Signed-off-by: James Youngman <jay at gnu.org>
---
 coreutils/ls.c |   33 ++++++++++++++++++++++++---------
 1 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/coreutils/ls.c b/coreutils/ls.c
index 72f58c2..dc78b5c 100644
--- a/coreutils/ls.c
+++ b/coreutils/ls.c
@@ -57,9 +57,11 @@ COLUMN_GAP      = 2,            /* includes the file type char */
 
 /* what is the overall style of the listing */
 STYLE_COLUMNS   = 1 << 21,      /* fill columns */
-STYLE_LONG      = 2 << 21,      /* one record per line, extended info */
-STYLE_SINGLE    = 3 << 21,      /* one record per line */
-STYLE_MASK      = STYLE_SINGLE,
+STYLE_SINGLE    = 2 << 21,      /* one record per line */
+STYLE_LONG      = 3 << 21,      /* one record per line, extended info */
+STYLE_MASK      = STYLE_LONG,
+/* If we add -m it's exclusive with respect to -l (last specified wins). */
+/* -x and -l are exclusive, but this works implicitly. */
 
 /* 51306 lrwxrwxrwx  1 root     root         2 May 11 01:43 /bin/view -> vi* */
 /* what file information will be listed */
@@ -102,13 +104,22 @@ SORT_VERSION    = 5 << 28,      /* sort by version */
 SORT_EXT        = 6 << 28,      /* sort by file name extension */
 SORT_DIR        = 7 << 28,      /* sort by file or directory */
 SORT_MASK       = (7 << 28) * ENABLE_FEATURE_LS_SORTFILES,
-
+/* TODO: -c (SORT_CTIME) and -u (SORT_ATIME) should be exclusive
+   (i.e. override the effect of the other), but making that work
+   requires giving them unique bits in the flags passed into getopt32,
+   so that we can make them complementary options.  We don't have
+   enough bits for that.  The existing *_TRIGGER mechanism can't be
+   used for this purpose, because it considers the options in the
+   order they appear in opt_flags, not the order they appear on the
+   command line.  
+*/
 /* which of the three times will be used */
 TIME_CHANGE     = (1 << 23) * ENABLE_FEATURE_LS_TIMESTAMPS,
 TIME_ACCESS     = (1 << 24) * ENABLE_FEATURE_LS_TIMESTAMPS,
 TIME_MASK       = (3 << 23) * ENABLE_FEATURE_LS_TIMESTAMPS,
 
 FOLLOW_LINKS    = (1 << 25) * ENABLE_FEATURE_LS_FOLLOWLINKS,
+/* -H and -L would be exclusive if -H were supported. */
 
 LS_DISP_HR      = (1 << 26) * ENABLE_FEATURE_HUMAN_READABLE,
 
@@ -123,6 +134,8 @@ SPLIT_SUBDIR    = 2,
 
 /* "[-]Cadil1", POSIX mandated options, busybox always supports */
 /* "[-]gnsx", POSIX non-mandated options, busybox always supports */
+/* "[-]L", POSIX mandated option, busybox does not support */
+/* "[-]m", POSIX non-mandated option, busybox does not support */
 /* "[-]Q" GNU option? busybox always supports */
 /* "[-]Ak" GNU options, busybox always supports */
 /* "[-]FLRctur", POSIX mandated options, busybox optionally supports */
@@ -741,7 +754,7 @@ static void showfiles(struct dnode **dn, unsigned nfiles)
 	unsigned nexttab = 0;
 	unsigned column_width = 0; /* used only by STYLE_COLUMNS */
 
-	if (all_fmt & STYLE_LONG) { /* STYLE_LONG or STYLE_SINGLE */
+	if ((all_fmt & STYLE_SINGLE) || ((all_fmt & STYLE_MASK) == STYLE_LONG)) {
 		ncols = 1;
 	} else {
 		/* find the longest file name, use that as the column width */
@@ -984,8 +997,8 @@ int ls_main(int argc UNUSED_PARAM, char **argv)
 
 	/* process options */
 	IF_FEATURE_LS_COLOR(applet_long_options = ls_longopts;)
+	opt_complementary = "C-1:C-l" IF_FEATURE_AUTOWIDTH(":T+:w+"); /* -T N, -w N */
 #if ENABLE_FEATURE_AUTOWIDTH
-	opt_complementary = "T+:w+"; /* -T N, -w N */
 	opt = getopt32(argv, ls_options, &tabstops, &terminal_width
 				IF_FEATURE_LS_COLOR(, &color_opt));
 #else
@@ -1006,7 +1019,7 @@ int ls_main(int argc UNUSED_PARAM, char **argv)
 			if (flags & TIME_MASK)
 				all_fmt &= ~TIME_MASK;
 			if (flags & LIST_CONTEXT)
-				all_fmt |= STYLE_SINGLE;
+			        all_fmt = (all_fmt & ~STYLE_MASK) | STYLE_SINGLE;
 			/* huh?? opt cannot be 'l' */
 			//if (LS_DISP_HR && opt == 'l')
 			//	all_fmt &= ~LS_DISP_HR;
@@ -1054,7 +1067,7 @@ int ls_main(int argc UNUSED_PARAM, char **argv)
 		if ((all_fmt & STYLE_MASK) == STYLE_LONG && (all_fmt & LIST_ID_NUMERIC))
 			all_fmt &= ~LIST_ID_NAME; /* don't list names if numeric uid */
 
-	/* choose a display format */
+	/* choose a display format if one was not already specified by an option */
 	if (!(all_fmt & STYLE_MASK))
 		all_fmt |= (isatty(STDOUT_FILENO) ? STYLE_COLUMNS : STYLE_SINGLE);
 
@@ -1070,7 +1083,9 @@ int ls_main(int argc UNUSED_PARAM, char **argv)
 	nfiles = 0;
 	do {
 		/* NB: follow links on command line unless -l or -s */
-		cur = my_stat(*argv, *argv, !(all_fmt & (STYLE_LONG|LIST_BLOCKS)));
+                const int follow = !(all_fmt & LIST_BLOCKS)
+                  && ((all_fmt & STYLE_MASK) != STYLE_LONG);
+		cur = my_stat(*argv, *argv, follow);
 		argv++;
 		if (!cur)
 			continue;
-- 
1.7.2.3