[PATCH 17/40] odb-helper: add odb_helper_init() to send 'init' instruction

From

Christian Couder <christian.couder@gmail.com>

Date

Jan 3, 2018, 16:33 UTC

Message-ID

<20180103163403.11303-18-chriscool@tuxfamily.org>

In-Reply-To

<20180103163403.11303-1-chriscool@tuxfamily.org>

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
---
 external-odb.c          | 13 +++++++++++-
 odb-helper.c            | 54 +++++++++++++++++++++++++++++++++++++++++++++++++
 odb-helper.h            | 12 +++++++++++
 t/t0400-external-odb.sh |  4 ++++
 4 files changed, 82 insertions(+), 1 deletion(-)

diff --git a/external-odb.c b/external-odb.c
index 81f2aa5fac..2622c12853 100644
--- a/external-odb.c
+++ b/external-odb.c
@@ -35,6 +35,8 @@ static int external_odb_config(const char *var, const char *value, void *data)
 
 	if (!strcmp(subkey, "promisorremote")) {
 		o->type = ODB_HELPER_GIT_REMOTE;
+		o->supported_capabilities |= ODB_HELPER_CAP_HAVE;
+		o->supported_capabilities |= ODB_HELPER_CAP_GET_DIRECT;
 		return git_config_string(&o->dealer, var, value);
 	}
 	if (!strcmp(subkey, "scriptcommand")) {
@@ -48,12 +50,16 @@ static int external_odb_config(const char *var, const char *value, void *data)
 static void external_odb_init(void)
 {
 	static int initialized;
+	struct odb_helper *o;
 
 	if (initialized || !use_external_odb)
 		return;
 	initialized = 1;
 
 	git_config(external_odb_config, NULL);
+
+	for (o = helpers; o; o = o->next)
+		odb_helper_init(o);
 }
 
 int has_external_odb(void)
@@ -77,9 +83,12 @@ int external_odb_has_object(const unsigned char *sha1)
 
 	external_odb_init();
 
-	for (o = helpers; o; o = o->next)
+	for (o = helpers; o; o = o->next) {
+		if (!(o->supported_capabilities & ODB_HELPER_CAP_HAVE))
+			return 1;
 		if (odb_helper_has_object(o, sha1))
 			return 1;
+	}
 	return 0;
 }
 
@@ -133,6 +142,8 @@ int external_odb_get_direct(const unsigned char *sha1)
 	external_odb_init();
 
 	for (o = helpers; o; o = o->next) {
+		if (!(o->supported_capabilities & ODB_HELPER_CAP_GET_DIRECT))
+			continue;
 		if (odb_helper_get_direct(o, sha1) < 0)
 			continue;
 		return 0;
diff --git a/odb-helper.c b/odb-helper.c
index c1a3443dc7..ea642fd438 100644
--- a/odb-helper.c
+++ b/odb-helper.c
@@ -6,6 +6,40 @@
 #include "sha1-lookup.h"
 #include "fetch-object.h"
 
+static void parse_capabilities(char *cap_buf,
+			       unsigned int *supported_capabilities,
+			       const char *process_name)
+{
+	struct string_list cap_list = STRING_LIST_INIT_NODUP;
+
+	string_list_split_in_place(&cap_list, cap_buf, '=', 1);
+
+	if (cap_list.nr == 2 && !strcmp(cap_list.items[0].string, "capability")) {
+		const char *cap_name = cap_list.items[1].string;
+
+		if (!strcmp(cap_name, "get_git_obj")) {
+			*supported_capabilities |= ODB_HELPER_CAP_GET_GIT_OBJ;
+		} else if (!strcmp(cap_name, "get_raw_obj")) {
+			*supported_capabilities |= ODB_HELPER_CAP_GET_RAW_OBJ;
+		} else if (!strcmp(cap_name, "get_direct")) {
+			*supported_capabilities |= ODB_HELPER_CAP_GET_DIRECT;
+		} else if (!strcmp(cap_name, "put_git_obj")) {
+			*supported_capabilities |= ODB_HELPER_CAP_PUT_GIT_OBJ;
+		} else if (!strcmp(cap_name, "put_raw_obj")) {
+			*supported_capabilities |= ODB_HELPER_CAP_PUT_RAW_OBJ;
+		} else if (!strcmp(cap_name, "put_direct")) {
+			*supported_capabilities |= ODB_HELPER_CAP_PUT_DIRECT;
+		} else if (!strcmp(cap_name, "have")) {
+			*supported_capabilities |= ODB_HELPER_CAP_HAVE;
+		} else {
+			warning("external process '%s' requested unsupported read-object capability '%s'",
+				process_name, cap_name);
+		}
+	}
+
+	string_list_clear(&cap_list, 0);
+}
+
 struct odb_helper *odb_helper_new(const char *name, int namelen)
 {
 	struct odb_helper *o;
@@ -80,6 +114,26 @@ static int odb_helper_finish(struct odb_helper *o,
 	return 0;
 }
 
+int odb_helper_init(struct odb_helper *o)
+{
+	struct odb_helper_cmd cmd;
+	FILE *fh;
+	struct strbuf line = STRBUF_INIT;
+
+	if (odb_helper_start(o, &cmd, "init") < 0)
+		return -1;
+
+	fh = xfdopen(cmd.child.out, "r");
+	while (strbuf_getline(&line, fh) != EOF)
+		parse_capabilities(line.buf, &o->supported_capabilities, o->name);
+
+	strbuf_release(&line);
+	fclose(fh);
+	odb_helper_finish(o, &cmd);
+
+	return 0;
+}
+
 static int parse_object_line(struct odb_helper_object *o, const char *line)
 {
 	char *end;
diff --git a/odb-helper.h b/odb-helper.h
index 4f2ac5e476..f8eac7f44c 100644
--- a/odb-helper.h
+++ b/odb-helper.h
@@ -1,6 +1,8 @@
 #ifndef ODB_HELPER_H
 #define ODB_HELPER_H
 
+#include "external-odb.h"
+
 enum odb_helper_type {
 	ODB_HELPER_NONE = 0,
 	ODB_HELPER_GIT_REMOTE,
@@ -9,10 +11,19 @@ enum odb_helper_type {
 	OBJ_HELPER_MAX
 };
 
+#define ODB_HELPER_CAP_GET_GIT_OBJ    (1u<<0)
+#define ODB_HELPER_CAP_GET_RAW_OBJ    (1u<<1)
+#define ODB_HELPER_CAP_GET_DIRECT     (1u<<2)
+#define ODB_HELPER_CAP_PUT_GIT_OBJ    (1u<<3)
+#define ODB_HELPER_CAP_PUT_RAW_OBJ    (1u<<4)
+#define ODB_HELPER_CAP_PUT_DIRECT     (1u<<5)
+#define ODB_HELPER_CAP_HAVE           (1u<<6)
+
 struct odb_helper {
 	const char *name;
 	const char *dealer;
 	enum odb_helper_type type;
+	unsigned int supported_capabilities;
 
 	struct odb_helper_object {
 		unsigned char sha1[20];
@@ -27,6 +38,7 @@ struct odb_helper {
 };
 
 extern struct odb_helper *odb_helper_new(const char *name, int namelen);
+extern int odb_helper_init(struct odb_helper *o);
 extern int odb_helper_has_object(struct odb_helper *o,
 				 const unsigned char *sha1);
 extern int odb_helper_get_object(struct odb_helper *o,
diff --git a/t/t0400-external-odb.sh b/t/t0400-external-odb.sh
index eaa3688a31..977fea852d 100755
--- a/t/t0400-external-odb.sh
+++ b/t/t0400-external-odb.sh
@@ -9,6 +9,10 @@ export ALT_SOURCE
 write_script odb-helper <<\EOF
 GIT_DIR=$ALT_SOURCE; export GIT_DIR
 case "$1" in
+init)
+	echo "capability=get_git_obj"
+	echo "capability=have"
+	;;
 have)
 	git cat-file --batch-check --batch-all-objects |
 	awk '{print $1 " " $3 " " $2}'

-- 
2.16.0.rc0.16.g82191dbc6c.dirty