[PATCH/RFC v2 1/6] Add infrastructure for translating Git with gettext

["Ævar Arnfjörð Bjarmason" <avarab@gmail.com>]

From: Jeff Epler <jepler@unpythonic.net>

Change the build process to use GNU's libintl if it's available. If
not we define our own skeleton replacement functions which degrade
gracefully to English.

Signed-off-by: Jeff Epler <jepler@unpythonic.net>
Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 Makefile    |   26 ++++++++++++
 gettext.c   |   17 ++++++++
 gettext.h   |   15 +++++++
 git.c       |    3 +
 wt-status.c |  129 ++++++++++++++++++++++++++++++-----------------------------
 5 files changed, 126 insertions(+), 64 deletions(-)
 create mode 100644 gettext.c
 create mode 100644 gettext.h

diff --git a/Makefile b/Makefile
index d5d6565..7989121 100644
--- a/Makefile
+++ b/Makefile
@@ -297,6 +297,8 @@ RPMBUILD = rpmbuild
 TCL_PATH = tclsh
 TCLTK_PATH = wish
 PTHREAD_LIBS = -lpthread
+XGETTEXT = xgettext
+MSGFMT = msgfmt
 
 export TCL_PATH TCLTK_PATH
 
@@ -523,6 +525,7 @@ LIB_H += userdiff.h
 LIB_H += utf8.h
 LIB_H += xdiff-interface.h
 LIB_H += xdiff/xdiff.h
+LIB_H += gettext.h
 
 LIB_OBJS += abspath.o
 LIB_OBJS += advice.o
@@ -564,6 +567,7 @@ LIB_OBJS += entry.o
 LIB_OBJS += environment.o
 LIB_OBJS += exec_cmd.o
 LIB_OBJS += fsck.o
+LIB_OBJS += gettext.o
 LIB_OBJS += graph.o
 LIB_OBJS += grep.o
 LIB_OBJS += hash.o
@@ -1386,6 +1390,12 @@ ifdef USE_NED_ALLOCATOR
        COMPAT_OBJS += compat/nedmalloc/nedmalloc.o
 endif
 
+ifdef NO_GETTEXT
+	COMPAT_CFLAGS += -DNO_GETTEXT
+else
+	LIBINTL = -lintl
+endif
+
 ifeq ($(TCLTK_PATH),)
 NO_TCLTK=NoThanks
 endif
@@ -1415,6 +1425,7 @@ ifndef V
 	QUIET_BUILT_IN = @echo '   ' BUILTIN $@;
 	QUIET_GEN      = @echo '   ' GEN $@;
 	QUIET_LNCP     = @echo '   ' LN/CP $@;
+	QUIET_MSGFMT   = @echo '   ' MSGFMT $@;
 	QUIET_SUBDIR0  = +@subdir=
 	QUIET_SUBDIR1  = ;$(NO_SUBDIR) echo '   ' SUBDIR $$subdir; \
 			 $(MAKE) $(PRINT_DIR) -C $$subdir
@@ -1442,6 +1453,7 @@ gitexecdir_SQ = $(subst ','\'',$(gitexecdir))
 template_dir_SQ = $(subst ','\'',$(template_dir))
 htmldir_SQ = $(subst ','\'',$(htmldir))
 prefix_SQ = $(subst ','\'',$(prefix))
+sharedir_SQ = $(subst ','\'',$(sharedir))
 
 SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
 PERL_PATH_SQ = $(subst ','\'',$(PERL_PATH))
@@ -1868,6 +1880,17 @@ cscope:
 	$(RM) cscope*
 	$(FIND) . -name '*.[hcS]' -print | xargs cscope -b
 
+pot:
+	$(XGETTEXT) -k_ -o po/git.pot $(C_OBJ:o=c)
+
+POFILES := $(wildcard po/*.po)
+MOFILES := $(patsubst po/%.po,share/locale/%/LC_MESSAGES/git.mo,$(POFILES))
+MODIRS := $(patsubst po/%.po,share/locale/%/LC_MESSAGES/,$(POFILES))
+all:: $(MOFILES)
+share/locale/%/LC_MESSAGES/git.mo: po/%.po
+	@mkdir -p $(dir $@)
+	$(QUIET_MSGFMT)$(MSGFMT) -o $@ $<
+
 ### Detect prefix changes
 TRACK_CFLAGS = $(subst ','\'',$(ALL_CFLAGS)):\
              $(bindir_SQ):$(gitexecdir_SQ):$(template_dir_SQ):$(prefix_SQ)
@@ -1980,6 +2003,9 @@ install: all
 	$(INSTALL) $(ALL_PROGRAMS) '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
 	$(INSTALL) -m 644 $(SCRIPT_LIB) '$(DESTDIR_SQ)$(gitexec_instdir_SQ)'
 	$(INSTALL) $(install_bindir_programs) '$(DESTDIR_SQ)$(bindir_SQ)'
+	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(sharedir_SQ)/locale'
+	(cd share && tar cf - locale) | \
+		(cd '$(DESTDIR_SQ)$(sharedir_SQ)' && umask 022 && tar xof -)
 	$(MAKE) -C templates DESTDIR='$(DESTDIR_SQ)' install
 ifndef NO_PERL
 	$(MAKE) -C perl prefix='$(prefix_SQ)' DESTDIR='$(DESTDIR_SQ)' install
diff --git a/gettext.c b/gettext.c
new file mode 100644
index 0000000..aadce19
--- /dev/null
+++ b/gettext.c
@@ -0,0 +1,17 @@
+#ifdef NO_GETTEXT
+void git_setup_gettext() {}
+#else
+#include "exec_cmd.h"
+#include <libintl.h>
+#include <stdlib.h>
+
+void git_setup_gettext() {
+    const char *podir = system_path("share/locale");
+    if(!podir) return;
+    char *ret = bindtextdomain("git", podir);
+    free((void*)podir);
+    ret = setlocale(LC_MESSAGES, "");
+    ret = setlocale(LC_CTYPE, "");
+    ret = textdomain("git");
+}
+#endif
diff --git a/gettext.h b/gettext.h
new file mode 100644
index 0000000..8b221b4
--- /dev/null
+++ b/gettext.h
@@ -0,0 +1,15 @@
+#ifndef GETTEXT_H
+#define GETTEXT_H
+
+void git_setup_gettext();
+
+#ifdef NO_GETTEXT
+#define _(s) (s)
+#define N_(s) (s)
+#else
+#include <libintl.h>
+#define _(s) gettext(s)
+#define N_(s) (s)
+#endif
+
+#endif
diff --git a/git.c b/git.c
index 99f0363..d749eab 100644
--- a/git.c
+++ b/git.c
@@ -3,6 +3,7 @@
 #include "cache.h"
 #include "quote.h"
 #include "run-command.h"
+#include "gettext.h"
 
 const char git_usage_string[] =
 	"git [--version] [--exec-path[=GIT_EXEC_PATH]] [--html-path]\n"
@@ -490,6 +491,8 @@ int main(int argc, const char **argv)
 	if (!cmd)
 		cmd = "git-help";
 
+	git_setup_gettext();
+
 	/*
 	 * "git-xxxx" is the same as "git xxxx", but we obviously:
 	 *
diff --git a/wt-status.c b/wt-status.c
index 14e0acc..70b4293 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -9,6 +9,7 @@
 #include "quote.h"
 #include "run-command.h"
 #include "remote.h"
+#include "gettext.h"
 
 static char default_wt_status_colors[][COLOR_MAXLEN] = {
 	GIT_COLOR_NORMAL, /* WT_STATUS_HEADER */
@@ -49,33 +50,33 @@ static void wt_status_print_unmerged_header(struct wt_status *s)
 {
 	const char *c = color(WT_STATUS_HEADER, s);
 
-	color_fprintf_ln(s->fp, c, "# Unmerged paths:");
+	color_fprintf_ln(s->fp, c, _("# Unmerged paths:"));
 	if (!advice_status_hints)
 		return;
 	if (s->in_merge)
 		;
 	else if (!s->is_initial)
-		color_fprintf_ln(s->fp, c, "#   (use \"git reset %s <file>...\" to unstage)", s->reference);
+		color_fprintf_ln(s->fp, c, _("#   (use \"git reset %s <file>...\" to unstage)"), s->reference);
 	else
-		color_fprintf_ln(s->fp, c, "#   (use \"git rm --cached <file>...\" to unstage)");
-	color_fprintf_ln(s->fp, c, "#   (use \"git add/rm <file>...\" as appropriate to mark resolution)");
-	color_fprintf_ln(s->fp, c, "#");
+		color_fprintf_ln(s->fp, c, _("#   (use \"git rm --cached <file>...\" to unstage)"));
+	color_fprintf_ln(s->fp, c, _("#   (use \"git add/rm <file>...\" as appropriate to mark resolution)"));
+	color_fprintf_ln(s->fp, c, _("#"));
 }
 
 static void wt_status_print_cached_header(struct wt_status *s)
 {
 	const char *c = color(WT_STATUS_HEADER, s);
 
-	color_fprintf_ln(s->fp, c, "# Changes to be committed:");
+	color_fprintf_ln(s->fp, c, _("# Changes to be committed:"));
 	if (!advice_status_hints)
 		return;
 	if (s->in_merge)
 		; /* NEEDSWORK: use "git reset --unresolve"??? */
 	else if (!s->is_initial)
-		color_fprintf_ln(s->fp, c, "#   (use \"git reset %s <file>...\" to unstage)", s->reference);
+		color_fprintf_ln(s->fp, c, _("#   (use \"git reset %s <file>...\" to unstage)"), s->reference);
 	else
-		color_fprintf_ln(s->fp, c, "#   (use \"git rm --cached <file>...\" to unstage)");
-	color_fprintf_ln(s->fp, c, "#");
+		color_fprintf_ln(s->fp, c, _("#   (use \"git rm --cached <file>...\" to unstage)"));
+	color_fprintf_ln(s->fp, c, _("#"));
 }
 
 static void wt_status_print_dirty_header(struct wt_status *s,
@@ -84,17 +85,17 @@ static void wt_status_print_dirty_header(struct wt_status *s,
 {
 	const char *c = color(WT_STATUS_HEADER, s);
 
-	color_fprintf_ln(s->fp, c, "# Changed but not updated:");
+	color_fprintf_ln(s->fp, c, _("# Changed but not updated:"));
 	if (!advice_status_hints)
 		return;
 	if (!has_deleted)
-		color_fprintf_ln(s->fp, c, "#   (use \"git add <file>...\" to update what will be committed)");
+		color_fprintf_ln(s->fp, c, _("#   (use \"git add <file>...\" to update what will be committed)"));
 	else
-		color_fprintf_ln(s->fp, c, "#   (use \"git add/rm <file>...\" to update what will be committed)");
-	color_fprintf_ln(s->fp, c, "#   (use \"git checkout -- <file>...\" to discard changes in working directory)");
+		color_fprintf_ln(s->fp, c, _("#   (use \"git add/rm <file>...\" to update what will be committed)"));
+	color_fprintf_ln(s->fp, c, _("#   (use \"git checkout -- <file>...\" to discard changes in working directory)"));
 	if (has_dirty_submodules)
-		color_fprintf_ln(s->fp, c, "#   (commit or discard the untracked or modified content in submodules)");
-	color_fprintf_ln(s->fp, c, "#");
+		color_fprintf_ln(s->fp, c, _("#   (commit or discard the untracked or modified content in submodules)"));
+	color_fprintf_ln(s->fp, c, _("#"));
 }
 
 static void wt_status_print_other_header(struct wt_status *s,
@@ -102,16 +103,16 @@ static void wt_status_print_other_header(struct wt_status *s,
 					 const char *how)
 {
 	const char *c = color(WT_STATUS_HEADER, s);
-	color_fprintf_ln(s->fp, c, "# %s files:", what);
+	color_fprintf_ln(s->fp, c, _("# %s files:"), what);
 	if (!advice_status_hints)
 		return;
-	color_fprintf_ln(s->fp, c, "#   (use \"git %s <file>...\" to include in what will be committed)", how);
-	color_fprintf_ln(s->fp, c, "#");
+	color_fprintf_ln(s->fp, c, _("#   (use \"git %s <file>...\" to include in what will be committed)"), how);
+	color_fprintf_ln(s->fp, c, _("#"));
 }
 
 static void wt_status_print_trailer(struct wt_status *s)
 {
-	color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), "#");
+	color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), _("#"));
 }
 
 #define quote_path quote_path_relative
@@ -122,20 +123,20 @@ static void wt_status_print_unmerged_data(struct wt_status *s,
 	const char *c = color(WT_STATUS_UNMERGED, s);
 	struct wt_status_change_data *d = it->util;
 	struct strbuf onebuf = STRBUF_INIT;
-	const char *one, *how = "bug";
+	const char *one, *how = _("bug");
 
 	one = quote_path(it->string, -1, &onebuf, s->prefix);
-	color_fprintf(s->fp, color(WT_STATUS_HEADER, s), "#\t");
+	color_fprintf(s->fp, color(WT_STATUS_HEADER, s), _("#\t"));
 	switch (d->stagemask) {
-	case 1: how = "both deleted:"; break;
-	case 2: how = "added by us:"; break;
-	case 3: how = "deleted by them:"; break;
-	case 4: how = "added by them:"; break;
-	case 5: how = "deleted by us:"; break;
-	case 6: how = "both added:"; break;
-	case 7: how = "both modified:"; break;
+	case 1: how = _("both deleted:"); break;
+	case 2: how = _("added by us:"); break;
+	case 3: how = _("deleted by them:"); break;
+	case 4: how = _("added by them:"); break;
+	case 5: how = _("deleted by us:"); break;
+	case 6: how = _("both added:"); break;
+	case 7: how = _("both modified:"); break;
 	}
-	color_fprintf(s->fp, c, "%-20s%s\n", how, one);
+	color_fprintf(s->fp, c, _("%-20s%s\n"), how, one);
 	strbuf_release(&onebuf);
 }
 
@@ -161,13 +162,13 @@ static void wt_status_print_change_data(struct wt_status *s,
 		break;
 	case WT_STATUS_CHANGED:
 		if (d->new_submodule_commits || d->dirty_submodule) {
-			strbuf_addstr(&extra, " (");
+			strbuf_addstr(&extra, _(" ("));
 			if (d->new_submodule_commits)
-				strbuf_addf(&extra, "new commits, ");
+				strbuf_addf(&extra, _("new commits, "));
 			if (d->dirty_submodule & DIRTY_SUBMODULE_MODIFIED)
-				strbuf_addf(&extra, "modified content, ");
+				strbuf_addf(&extra, _("modified content, "));
 			if (d->dirty_submodule & DIRTY_SUBMODULE_UNTRACKED)
-				strbuf_addf(&extra, "untracked content, ");
+				strbuf_addf(&extra, _("untracked content, "));
 			strbuf_setlen(&extra, extra.len - 2);
 			strbuf_addch(&extra, ')');
 		}
@@ -178,40 +179,40 @@ static void wt_status_print_change_data(struct wt_status *s,
 	one = quote_path(one_name, -1, &onebuf, s->prefix);
 	two = quote_path(two_name, -1, &twobuf, s->prefix);
 
-	color_fprintf(s->fp, color(WT_STATUS_HEADER, s), "#\t");
+	color_fprintf(s->fp, color(WT_STATUS_HEADER, s), _("#\t"));
 	switch (status) {
 	case DIFF_STATUS_ADDED:
-		color_fprintf(s->fp, c, "new file:   %s", one);
+		color_fprintf(s->fp, c, _("new file:   %s"), one);
 		break;
 	case DIFF_STATUS_COPIED:
-		color_fprintf(s->fp, c, "copied:     %s -> %s", one, two);
+		color_fprintf(s->fp, c, _("copied:     %s -> %s"), one, two);
 		break;
 	case DIFF_STATUS_DELETED:
-		color_fprintf(s->fp, c, "deleted:    %s", one);
+		color_fprintf(s->fp, c, _("deleted:    %s"), one);
 		break;
 	case DIFF_STATUS_MODIFIED:
-		color_fprintf(s->fp, c, "modified:   %s", one);
+		color_fprintf(s->fp, c, _("modified:   %s"), one);
 		break;
 	case DIFF_STATUS_RENAMED:
-		color_fprintf(s->fp, c, "renamed:    %s -> %s", one, two);
+		color_fprintf(s->fp, c, _("renamed:    %s -> %s"), one, two);
 		break;
 	case DIFF_STATUS_TYPE_CHANGED:
-		color_fprintf(s->fp, c, "typechange: %s", one);
+		color_fprintf(s->fp, c, _("typechange: %s"), one);
 		break;
 	case DIFF_STATUS_UNKNOWN:
-		color_fprintf(s->fp, c, "unknown:    %s", one);
+		color_fprintf(s->fp, c, _("unknown:    %s"), one);
 		break;
 	case DIFF_STATUS_UNMERGED:
-		color_fprintf(s->fp, c, "unmerged:   %s", one);
+		color_fprintf(s->fp, c, _("unmerged:   %s"), one);
 		break;
 	default:
-		die("bug: unhandled diff status %c", status);
+		die(_("bug: unhandled diff status %c"), status);
 	}
 	if (extra.len) {
-		color_fprintf(s->fp, color(WT_STATUS_HEADER, s), "%s", extra.buf);
+		color_fprintf(s->fp, color(WT_STATUS_HEADER, s), _("%s"), extra.buf);
 		strbuf_release(&extra);
 	}
-	fprintf(s->fp, "\n");
+	fprintf(s->fp, _("\n"));
 	strbuf_release(&onebuf);
 	strbuf_release(&twobuf);
 }
@@ -618,14 +619,14 @@ void wt_status_print(struct wt_status *s)
 	const char *branch_color = color(WT_STATUS_HEADER, s);
 
 	if (s->branch) {
-		const char *on_what = "On branch ";
+		const char *on_what = _("On branch ");
 		const char *branch_name = s->branch;
 		if (!prefixcmp(branch_name, "refs/heads/"))
 			branch_name += 11;
 		else if (!strcmp(branch_name, "HEAD")) {
 			branch_name = "";
 			branch_color = color(WT_STATUS_NOBRANCH, s);
-			on_what = "Not currently on any branch.";
+			on_what = _("Not currently on any branch.");
 		}
 		color_fprintf(s->fp, color(WT_STATUS_HEADER, s), "# ");
 		color_fprintf_ln(s->fp, branch_color, "%s%s", on_what, branch_name);
@@ -634,9 +635,9 @@ void wt_status_print(struct wt_status *s)
 	}
 
 	if (s->is_initial) {
-		color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), "#");
-		color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), "# Initial commit");
-		color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), "#");
+		color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), _("#"));
+		color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), _("# Initial commit"));
+		color_fprintf_ln(s->fp, color(WT_STATUS_HEADER, s), _("#"));
 	}
 
 	wt_status_print_updated(s);
@@ -647,38 +648,38 @@ void wt_status_print(struct wt_status *s)
 		wt_status_print_submodule_summary(s, 1);  /* unstaged */
 	}
 	if (s->show_untracked_files) {
-		wt_status_print_other(s, &s->untracked, "Untracked", "add");
+		wt_status_print_other(s, &s->untracked, _("Untracked"), _("add"));
 		if (s->show_ignored_files)
-			wt_status_print_other(s, &s->ignored, "Ignored", "add -f");
+			wt_status_print_other(s, &s->ignored, _("Ignored"), _("add -f"));
 	} else if (s->commitable)
-		fprintf(s->fp, "# Untracked files not listed%s\n",
+		fprintf(s->fp, _("# Untracked files not listed%s\n"),
 			advice_status_hints
-			? " (use -u option to show untracked files)" : "");
+			? _(" (use -u option to show untracked files)") : "");
 
 	if (s->verbose)
 		wt_status_print_verbose(s);
 	if (!s->commitable) {
 		if (s->amend)
-			fprintf(s->fp, "# No changes\n");
+			fprintf(s->fp, _("# No changes\n"));
 		else if (s->nowarn)
 			; /* nothing */
 		else if (s->workdir_dirty)
-			printf("no changes added to commit%s\n",
+			printf(_("no changes added to commit%s\n"),
 				advice_status_hints
-				? " (use \"git add\" and/or \"git commit -a\")" : "");
+				? _(" (use \"git add\" and/or \"git commit -a\")") : "");
 		else if (s->untracked.nr)
-			printf("nothing added to commit but untracked files present%s\n",
+			printf(_("nothing added to commit but untracked files present%s\n"),
 				advice_status_hints
-				? " (use \"git add\" to track)" : "");
+				? _(" (use \"git add\" to track)") : "");
 		else if (s->is_initial)
 			printf("nothing to commit%s\n", advice_status_hints
-				? " (create/copy files and use \"git add\" to track)" : "");
+				? _(" (create/copy files and use \"git add\" to track)") : "");
 		else if (!s->show_untracked_files)
-			printf("nothing to commit%s\n", advice_status_hints
-				? " (use -u to show untracked files)" : "");
+			printf(_("nothing to commit%s\n"), advice_status_hints
+				? _(" (use -u to show untracked files)") : "");
 		else
-			printf("nothing to commit%s\n", advice_status_hints
-				? " (working directory clean)" : "");
+			printf(_("nothing to commit%s\n"), advice_status_hints
+				? _(" (working directory clean)") : "");
 	}
 }
 
-- 
1.7.1.248.gcd6d1