submodule: rewrite `module_name` shell function in C

This implements the helper `name` in C instead of shell,
yielding a nice performance boost.

Before this patch, I measured a time (best out of three):

$ time ./t7400-submodule-basic.sh  >/dev/null
real	0m11.066s
user	0m3.348s
sys	0m8.534s

With this patch applied I measured (also best out of three)

$ time ./t7400-submodule-basic.sh  >/dev/null
real	0m10.063s
user	0m3.044s
sys	0m7.487s

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
index 10db4e6f6a5c5ec38bfe2ce85c524c97aa85e561..bc79c41b5870868b3618710f316ac24ac1f70fe8 100644 (file)
--- a/builtin/submodule--helper.c
+++ b/builtin/submodule--helper.c
@@ -5,6 +5,9 @@
 #include "pathspec.h"
 #include "dir.h"
 #include "utf8.h"
+#include "submodule.h"
+#include "submodule-config.h"
+#include "string-list.h"
 
 struct module_list {
        const struct cache_entry **entries;
@@ -102,6 +105,24 @@ static int module_list(int argc, const char **argv, const char *prefix)
        return 0;
 }
 
+static int module_name(int argc, const char **argv, const char *prefix)
+{
+       const struct submodule *sub;
+
+       if (argc != 2)
+               usage(_("git submodule--helper name <path>"));
+
+       gitmodules_config();
+       sub = submodule_from_path(null_sha1, argv[1]);
+
+       if (!sub)
+               die(_("no submodule mapping found in .gitmodules for path '%s'"),
+                   argv[1]);
+
+       printf("%s\n", sub->name);
+
+       return 0;
+}
 
 struct cmd_struct {
        const char *cmd;
@@ -110,6 +131,7 @@ struct cmd_struct {
 
 static struct cmd_struct commands[] = {
        {"list", module_list},
+       {"name", module_name},
 };
 
 int cmd_submodule__helper(int argc, const char **argv, const char *prefix)

diff --git a/git-submodule.sh b/git-submodule.sh
index 95c04fc60ce7a846ae96e528a873693ab1c3a8d0..2be8da2396eb11dbac887049dae1c8f0dea849d6 100755 (executable)
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -178,24 +178,6 @@ get_submodule_config () {
        printf '%s' "${value:-$default}"
 }
 
-
-#
-# Map submodule path to submodule name
-#
-# $1 = path
-#
-module_name()
-{
-       # Do we have "submodule.<something>.path = $1" defined in .gitmodules file?
-       sm_path="$1"
-       re=$(printf '%s\n' "$1" | sed -e 's/[].[^$\\*]/\\&/g')
-       name=$( git config -f .gitmodules --get-regexp '^submodule\..*\.path$' |
-               sed -n -e 's|^submodule\.\(.*\)\.path '"$re"'$|\1|p' )
-       test -z "$name" &&
-       die "$(eval_gettext "No submodule mapping found in .gitmodules for path '\$sm_path'")"
-       printf '%s\n' "$name"
-}
-
 #
 # Clone a submodule
 #
@@ -498,7 +480,7 @@ cmd_foreach()
                then
                        displaypath=$(relative_path "$sm_path")
                        say "$(eval_gettext "Entering '\$prefix\$displaypath'")"
-                       name=$(module_name "$sm_path")
+                       name=$(git submodule--helper name "$sm_path")
                        (
                                prefix="$prefix$sm_path/"
                                clear_local_git_env
@@ -554,7 +536,7 @@ cmd_init()
        while read mode sha1 stage sm_path
        do
                die_if_unmatched "$mode"
-               name=$(module_name "$sm_path") || exit
+               name=$(git submodule--helper name "$sm_path") || exit
 
                displaypath=$(relative_path "$sm_path")
 
@@ -636,7 +618,7 @@ cmd_deinit()
        while read mode sha1 stage sm_path
        do
                die_if_unmatched "$mode"
-               name=$(module_name "$sm_path") || exit
+               name=$(git submodule--helper name "$sm_path") || exit
 
                displaypath=$(relative_path "$sm_path")
 
@@ -758,7 +740,7 @@ cmd_update()
                        echo >&2 "Skipping unmerged submodule $prefix$sm_path"
                        continue
                fi
-               name=$(module_name "$sm_path") || exit
+               name=$(git submodule--helper name "$sm_path") || exit
                url=$(git config submodule."$name".url)
                branch=$(get_submodule_config "$name" branch master)
                if ! test -z "$update"
@@ -1022,7 +1004,7 @@ cmd_summary() {
                        # Respect the ignore setting for --for-status.
                        if test -n "$for_status"
                        then
-                               name=$(module_name "$sm_path")
+                               name=$(git submodule--helper name "$sm_path")
                                ignore_config=$(get_submodule_config "$name" ignore none)
                                test $status != A && test $ignore_config = all && continue
                        fi
@@ -1184,7 +1166,7 @@ cmd_status()
        while read mode sha1 stage sm_path
        do
                die_if_unmatched "$mode"
-               name=$(module_name "$sm_path") || exit
+               name=$(git submodule--helper name "$sm_path") || exit
                url=$(git config submodule."$name".url)
                displaypath=$(relative_path "$prefix$sm_path")
                if test "$stage" = U
@@ -1261,7 +1243,7 @@ cmd_sync()
        while read mode sha1 stage sm_path
        do
                die_if_unmatched "$mode"
-               name=$(module_name "$sm_path")
+               name=$(git submodule--helper name "$sm_path")
                url=$(git config -f .gitmodules --get submodule."$name".url)
 
                # Possibly a url relative to parent