UTF-8: introduce i18n.logoutputencoding.

It is plausible for somebody to want to view the commit log in a
different encoding from i18n.commitencoding -- the project's
policy may be UTF-8 and the user may be using a commit message
hook to run iconv to conform to that policy (and either not have
i18n.commitencoding to default to UTF-8 or have it explicitly
set to UTF-8).  Even then, Latin-1 may be more convenient for
the usual pager and the terminal the user uses.

The new variable i18n.logoutputencoding is used in preference to
i18n.commitencoding to decide what encoding to recode the log
output in when git-log and friends formats the commit log message.

Signed-off-by: Junio C Hamano <junkio@cox.net>

15 files changed, 160 insertions, 23 deletions

diff --git a/Documentation/config.txt b/Documentation/config.txt
index 22482d6a94..ffef3abfb6 100644
--- a/Documentation/config.txt
+++ b/Documentation/config.txt
@@ -248,6 +248,10 @@ i18n.commitEncoding::
 	browser (and possibly at other places in the future or in other
 	porcelains). See e.g. gitlink:git-mailinfo[1]. Defaults to 'utf-8'.
 
+i18n.logOutputEncoding::
+	Character encoding the commit messages are converted to when
+	running `git-log` and friends.
+
 log.showroot::
 	If true, the initial commit will be shown as a big creation event.
 	This is equivalent to a diff against an empty tree.
diff --git a/builtin-commit-tree.c b/builtin-commit-tree.c
index 33c29f7495..146aaffd28 100644
--- a/builtin-commit-tree.c
+++ b/builtin-commit-tree.c
@@ -118,7 +118,9 @@ int cmd_commit_tree(int argc, const char **argv, const char *prefix)
 			parents++;
 	}
 
-	encoding_is_utf8 = !strcmp(git_commit_encoding, "utf-8");
+	/* Not having i18n.commitencoding is the same as having utf-8 */
+	encoding_is_utf8 = (!git_commit_encoding ||
+			    !strcmp(git_commit_encoding, "utf-8"));
 
 	init_buffer(&buffer, &size);
 	add_buffer(&buffer, &size, "tree %s\n", sha1_to_hex(tree_sha1));
diff --git a/builtin-log.c b/builtin-log.c
index b7e47cb5fe..a59b4acef1 100644
--- a/builtin-log.c
+++ b/builtin-log.c
@@ -33,13 +33,10 @@ static void cmd_log_init(int argc, const char **argv, const char *prefix,
 		const char *arg = argv[i];
 		if (!strncmp(arg, "--encoding=", 11)) {
 			arg += 11;
-			if (MAX_ENCODING_LENGTH <= strlen(arg))
-				die(" Value of output encoding '%s' too long",
-				    arg);
 			if (strcmp(arg, "none"))
-				strcpy(git_commit_encoding, arg);
+				git_log_output_encoding = strdup(arg);
 			else
-				git_commit_encoding[0] = 0;
+				git_log_output_encoding = "";
 		}
 		else
 			die("unrecognized argument: %s", arg);
diff --git a/builtin-mailinfo.c b/builtin-mailinfo.c
index 507b93f6a7..a67f3eb90b 100644
--- a/builtin-mailinfo.c
+++ b/builtin-mailinfo.c
@@ -806,7 +806,8 @@ int cmd_mailinfo(int argc, const char **argv, const char *prefix)
 		if (!strcmp(argv[1], "-k"))
 			keep_subject = 1;
 		else if (!strcmp(argv[1], "-u"))
-			metainfo_charset = git_commit_encoding;
+			metainfo_charset = (git_commit_encoding
+					    ? git_commit_encoding : "utf-8");
 		else if (!strncmp(argv[1], "--encoding=", 11))
 			metainfo_charset = argv[1] + 11;
 		else
diff --git a/cache.h b/cache.h
index 4943056c19..29dd290c92 100644
--- a/cache.h
+++ b/cache.h
@@ -416,8 +416,8 @@ extern int check_repository_format_version(const char *var, const char *value);
 extern char git_default_email[MAX_GITNAME];
 extern char git_default_name[MAX_GITNAME];
 
-#define MAX_ENCODING_LENGTH 64
-extern char git_commit_encoding[MAX_ENCODING_LENGTH];
+extern char *git_commit_encoding;
+extern char *git_log_output_encoding;
 
 extern int copy_fd(int ifd, int ofd);
 extern void write_or_die(int fd, const void *buf, size_t count);
diff --git a/commit.c b/commit.c
index df4bc0775a..6f2839a5cd 100644
--- a/commit.c
+++ b/commit.c
@@ -592,12 +592,20 @@ static char *get_header(const struct commit *commit, const char *key)
 
 static char *logmsg_reencode(const struct commit *commit)
 {
-	char *encoding = get_header(commit, "encoding");
+	char *encoding;
 	char *out;
+	char *output_encoding = (git_log_output_encoding
+				 ? git_log_output_encoding
+				 : git_commit_encoding);
 
-	if (!encoding || !strcmp(encoding, git_commit_encoding))
+	if (!output_encoding)
 		return NULL;
-	out = reencode_string(commit->buffer, git_commit_encoding, encoding);
+	encoding = get_header(commit, "encoding");
+	if (!encoding || !strcmp(encoding, output_encoding)) {
+		free(encoding);
+		return NULL;
+	}
+	out = reencode_string(commit->buffer, output_encoding, encoding);
 	free(encoding);
 	if (!out)
 		return NULL;
@@ -618,15 +626,10 @@ unsigned long pretty_print_commit(enum cmit_fmt fmt,
 	int parents_shown = 0;
 	const char *msg = commit->buffer;
 	int plain_non_ascii = 0;
-	char *reencoded = NULL;
+	char *reencoded = logmsg_reencode(commit);
 
-	if (*git_commit_encoding) {
-		reencoded = logmsg_reencode(commit);
-		if (reencoded) {
-			msg = reencoded;
-			len = strlen(msg);
-		}
-	}
+	if (reencoded)
+		msg = reencoded;
 
 	if (fmt == CMIT_FMT_ONELINE || fmt == CMIT_FMT_EMAIL)
 		indent = 0;
@@ -643,7 +646,7 @@ unsigned long pretty_print_commit(enum cmit_fmt fmt,
 		for (in_body = i = 0; (ch = msg[i]) && i < len; i++) {
 			if (!in_body) {
 				/* author could be non 7-bit ASCII but
-				 * the log may so; skip over the
+				 * the log may be so; skip over the
 				 * header part first.
 				 */
 				if (ch == '\n' &&
diff --git a/config.c b/config.c
index 1662a4626e..fcccf7e2a4 100644
--- a/config.c
+++ b/config.c
@@ -309,10 +309,16 @@ int git_default_config(const char *var, const char *value)
 	}
 
 	if (!strcmp(var, "i18n.commitencoding")) {
-		strlcpy(git_commit_encoding, value, sizeof(git_commit_encoding));
+		git_commit_encoding = strdup(value);
 		return 0;
 	}
 
+	if (!strcmp(var, "i18n.logoutputencoding")) {
+		git_log_output_encoding = strdup(value);
+		return 0;
+	}
+
+
 	if (!strcmp(var, "pager.color") || !strcmp(var, "color.pager")) {
 		pager_use_color = git_config_bool(var,value);
 		return 0;
diff --git a/contrib/completion/git-completion.bash b/contrib/completion/git-completion.bash
index 234cd0954b..7c7520ea29 100755
--- a/contrib/completion/git-completion.bash
+++ b/contrib/completion/git-completion.bash
@@ -711,6 +711,7 @@ _git_repo_config ()
 		core.compression
 		core.legacyHeaders
 		i18n.commitEncoding
+		i18n.logOutputEncoding
 		diff.color
 		color.diff
 		diff.renameLimit
diff --git a/environment.c b/environment.c
index f8c7dbcead..a1502c4e87 100644
--- a/environment.c
+++ b/environment.c
@@ -18,7 +18,8 @@ int prefer_symlink_refs;
 int log_all_ref_updates;
 int warn_ambiguous_refs = 1;
 int repository_format_version;
-char git_commit_encoding[MAX_ENCODING_LENGTH] = "utf-8";
+char *git_commit_encoding;
+char *git_log_output_encoding;
 int shared_repository = PERM_UMASK;
 const char *apply_default_whitespace;
 int zlib_compression_level = Z_DEFAULT_COMPRESSION;
diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
new file mode 100755
index 0000000000..3606ed2efa
--- /dev/null
+++ b/t/t3900-i18n-commit.sh
@@ -0,0 +1,104 @@
+#!/bin/sh
+#
+# Copyright (c) 2006 Junio C Hamano
+#
+
+test_description='commit and log output encodings'
+
+. ./test-lib.sh
+
+compare_with () {
+	git-show -s "$1" | sed -e '1,/^$/d' -e 's/^    //' -e '$d' >current &&
+	diff -u current "$2"
+}
+
+test_expect_success setup '
+	: >F &&
+	git-add F &&
+	T=$(git-write-tree) &&
+	C=$(git-commit-tree $T <../t3900/1-UTF-8.txt) &&
+	git-update-ref HEAD $C &&
+	git-tag C0
+'
+
+test_expect_success 'no encoding header for base case' '
+	E=$(git-cat-file commit C0 | sed -ne "s/^encoding //p") &&
+	test z = "z$E"
+'
+
+for H in ISO-8859-1 EUCJP ISO2022JP
+do
+	test_expect_success "$H setup" '
+		git-repo-config i18n.commitencoding $H &&
+		git-checkout -b $H C0 &&
+		echo $H >F &&
+		git-commit -a -F ../t3900/$H.txt
+	'
+done
+
+for H in ISO-8859-1 EUCJP ISO2022JP
+do
+	test_expect_success "check encoding header for $H" '
+		E=$(git-cat-file commit '$H' | sed -ne "s/^encoding //p") &&
+		test "z$E" = "z'$H'"
+	'
+done
+
+test_expect_success 'repo-config to remove customization' '
+	git-repo-config --unset-all i18n.commitencoding &&
+	if Z=$(git-repo-config --get-all i18n.commitencoding)
+	then
+		echo Oops, should have failed.
+		false
+	else
+		test z = "z$Z"
+	fi &&
+	git-repo-config i18n.commitencoding utf-8
+'
+
+test_expect_success 'ISO-8859-1 should be shown in UTF-8 now' '
+	compare_with ISO-8859-1 ../t3900/1-UTF-8.txt
+'
+
+for H in EUCJP ISO2022JP
+do
+	test_expect_success "$H should be shown in UTF-8 now" '
+		compare_with '$H' ../t3900/2-UTF-8.txt
+	'
+done
+
+test_expect_success 'repo-config to add customization' '
+	git-repo-config --unset-all i18n.commitencoding &&
+	if Z=$(git-repo-config --get-all i18n.commitencoding)
+	then
+		echo Oops, should have failed.
+		false
+	else
+		test z = "z$Z"
+	fi
+'
+
+for H in ISO-8859-1 EUCJP ISO2022JP
+do
+	test_expect_success "$H should be shown in itself now" '
+		git-repo-config i18n.commitencoding '$H' &&
+		compare_with '$H' ../t3900/'$H'.txt
+	'
+done
+
+test_expect_success 'repo-config to tweak customization' '
+	git-repo-config i18n.logoutputencoding utf-8
+'
+
+test_expect_success 'ISO-8859-1 should be shown in UTF-8 now' '
+	compare_with ISO-8859-1 ../t3900/1-UTF-8.txt
+'
+
+for H in EUCJP ISO2022JP
+do
+	test_expect_success "$H should be shown in UTF-8 now" '
+		compare_with '$H' ../t3900/2-UTF-8.txt
+	'
+done
+
+test_done
diff --git a/t/t3900/1-UTF-8.txt b/t/t3900/1-UTF-8.txt
new file mode 100644
index 0000000000..ee31e19738
--- /dev/null
+++ b/t/t3900/1-UTF-8.txt
@@ -0,0 +1,3 @@
+ÄËÑÏÖ
+
+Ábçdèfg
diff --git a/t/t3900/2-UTF-8.txt b/t/t3900/2-UTF-8.txt
new file mode 100644
index 0000000000..63f4f8f121
--- /dev/null
+++ b/t/t3900/2-UTF-8.txt
@@ -0,0 +1,4 @@
+はれひほふ
+
+しているのが、いるので。
+濱浜ほれぷりぽれまびぐりろへ。
diff --git a/t/t3900/EUCJP.txt b/t/t3900/EUCJP.txt
new file mode 100644
index 0000000000..546f2aac01
--- /dev/null
+++ b/t/t3900/EUCJP.txt
@@ -0,0 +1,4 @@
+�Ϥ�Ҥۤ�
+
+���Ƥ���Τ�������Τǡ�
+���ͤۤ�פ�ݤ�ޤӤ�����ء�
diff --git a/t/t3900/ISO-8859-1.txt b/t/t3900/ISO-8859-1.txt
new file mode 100644
index 0000000000..7cbef0ee6f
--- /dev/null
+++ b/t/t3900/ISO-8859-1.txt
@@ -0,0 +1,3 @@
+�����
+
+�b�d�fg
diff --git a/t/t3900/ISO2022JP.txt b/t/t3900/ISO2022JP.txt
new file mode 100644
index 0000000000..74b533042f
--- /dev/null
+++ b/t/t3900/ISO2022JP.txt
@@ -0,0 +1,4 @@
+$B$O$l$R$[$U(B
+
+$B$7$F$$$k$N$,!"$$$k$N$G!#(B
+$B_@IM$[$l$W$j$]$l$^$S$0$j$m$X!#(B