git/list[1] front-page[2] threads[3] people[4] search[5] about
 

[PATCH] Give better default modes to merge results.

From
Junio C Hamano <junkio@cox.net>
Date
Apr 20, 2005, 09:55 UTC
Message-ID
<7vsm1lkc1g.fsf@assigned-by-dhcp.cox.net>

As shipped, the example git-merge-one-file-script often leaves the merge result with not-so-useful mode bits, especially with glibc 2.0.7 or later whose mkstemp() creates temporary file with mode 0600. This contradicts the way checkout-cache creates new files, which is to use 0666 (or 0777 for files with executable bit on) and let the umask mechanism to take care of adjusting it to the user's preference.

This patch fixes this problem by (1) passing the executable bits for 3 stages from merge-cache to the merge script, and by (2) adjusting the example script to make use of that information.

For backward compatibility with existing merge-one-file-script people may already have developed, the additional 3 arguments are passed after the filename (i.e. as $5, $6 and $7). This does not logically look so nice, but the older scripts can and would just ignore these new parameters.

The patch also fixes some shell quoting problems the original sample script had with the resulting filename "$4". Unlike all the other arguments, this must be quoted to prevent it from being split via shell's $IFS mechanism.

Signed-off-by: Junio C Hamano <junkio@cox.net>
---
 git-merge-one-file-script |   35 +++++++++++++++++++++++++++--------
 merge-cache.c             |   18 ++++++++++++++----
 2 files changed, 41 insertions(+), 12 deletions(-)
--- a/git-merge-one-file-script
+++ b/git-merge-one-file-script
@@ -6,7 +6,9 @@
 #   $2 - file in branch1 SHA1 (or empty)
 #   $3 - file in branch2 SHA1 (or empty)
 #   $4 - pathname in repository
-#
+#   $5 - original file executable bit ('x' or '-' or empty)
+#   $6 - file in branch1  executable bit ('x' or '-' or empty)
+#   $7 - file in branch2  executable bit ('x' or '-' or empty)
 #
 # Handle some trivial cases.. The _really_ trivial cases have
 # been handled already by read-tree, but that one doesn't
@@ -24,17 +26,29 @@ case "${1:-.}${2:-.}${3:-.}" in
 #
 "$1.." | "$1.$1" | "$1$1.")
 	rm -f -- "$4"
-	update-cache --remove -- "$4"
-	exit 0
+	exec update-cache --remove -- "$4"
 	;;
 
 #
 # added in one, or added identically in both
 #
 ".$2." | "..$3" | ".$2$2")
-	mv $(unpack-file "${2:-$3}") "$4"
-	update-cache --add -- "$4" ;# needs filemode fix.
-	exit 0
+
+	# This part is convoluted but necessary to get a sane
+	# default mode bits.  We let the shell to honor default
+	# umask when creating the file, and then rely on chmod +x
+	# to again honor umask.  It used to "mv" the file created
+	# in mode 0600 by unpack-file to "$4", which was almost
+	# always wrong.
+
+	tmp=$(unpack-file "${2:-$3}") &&
+	rm -f "$4" &&
+	cat "$tmp" >"$4" &&
+	case "$6$7" in
+	*x*) chmod +x "$4" ;;
+	esac &&
+	rm -f "$tmp" || exit
+	exec update-cache --add -- "$4"
 	;;
 
 #
@@ -50,11 +64,16 @@ case "${1:-.}${2:-.}${3:-.}" in
 		echo Leaving conflict merge in $src2
 		exit 1
 	fi
-	cp "$src2" "$4" && update-cache --add -- "$4" && exit 0
+	rm -f "$4" &&
+	cat "$src2" >"$4" &&
+	case "$5$6$7" in
+	*x*) chmod +x "$4" ;;
+	esac || exit
+	exec update-cache --add -- "$4"
 	;;
 
 *)
-	echo "Not handling case $1 -> $2 -> $3"
+	echo "Not handling case $1($5) -> $2($6) -> $3($7)"
 	;;
 esac
 exit 1
--- a/merge-cache.c
+++ b/merge-cache.c
@@ -4,7 +4,7 @@
 #include "cache.h"
 
 static const char *pgm = NULL;
-static const char *arguments[5];
+static const char *arguments[8];
 
 static void run_program(void)
 {
@@ -18,6 +18,9 @@ static void run_program(void)
 			    arguments[2],
 			    arguments[3],
 			    arguments[4],
+			    arguments[5],
+			    arguments[6],
+			    arguments[7],
 			    NULL);
 		die("unable to execute '%s'", pgm);
 	}
@@ -36,17 +39,24 @@ static int merge_entry(int pos, const ch
 	arguments[2] = "";
 	arguments[3] = "";
 	arguments[4] = path;
+	arguments[5] = "";
+	arguments[6] = "";
+	arguments[7] = "";
 	found = 0;
 	do {
-		static char hexbuf[4][60];
+		static char hexbuf[3][41];
+		static char xbit[3][2];
 		struct cache_entry *ce = active_cache[pos];
 		int stage = ce_stage(ce);
 
 		if (strcmp(ce->name, path))
 			break;
 		found++;
-		strcpy(hexbuf[stage], sha1_to_hex(ce->sha1));
-		arguments[stage] = hexbuf[stage];
+		strcpy(hexbuf[stage-1], sha1_to_hex(ce->sha1));
+		arguments[stage] = hexbuf[stage-1];
+		xbit[stage-1][0] = (ntohl(ce->ce_mode) & 0100) ? 'x' : '-';
+		xbit[stage-1][1] = 0;
+		arguments[stage+4] = xbit[stage-1];
 	} while (++pos < active_nr);
 	if (!found)
 		die("merge-cache: %s not in the cache", path);
Message 1 of 1 in “Give better default modes to merge results.”
  1. Give better default modes to merge results.Junio C Hamano, Apr 20, 2005

Read the whole thread, see it on lore, or plain text.

$ cat FOOTERMessages come from the public archive at lore.kernel.org/git, fetched every hour. The front page is chosen and written each morning by an AI editor and can be wrong; the threads themselves are the record. About and API. For agents: an MCP server at https://gitlist.dev/mcp, and any thread, story or person page as Markdown by adding .md to its URL (or sending Accept: text/markdown). Details in /llms.txt.