From: Ben Peart <benpe...@microsoft.com>
Signed-off-by: Ben Peart <benpe...@microsoft.com>
Signed-off-by: Christian Couder <chrisc...@tuxfamily.org>
---
odb-helper.c | 202 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
odb-helper.h | 5 ++
sha1_file.c | 33 +++++++++-
3 files changed, 227 insertions(+), 13 deletions(-)
diff --git a/odb-helper.c b/odb-helper.c
index 5fb56c6135..20e83cb55a 100644
--- a/odb-helper.c
+++ b/odb-helper.c
@@ -4,6 +4,187 @@
#include "odb-helper.h"
#include "run-command.h"
#include "sha1-lookup.h"
+#include "sub-process.h"
+#include "pkt-line.h"
+#include "sigchain.h"
+
+struct read_object_process {
+ struct subprocess_entry subprocess;
+ unsigned int supported_capabilities;
+};
+
+static int subprocess_map_initialized;
+static struct hashmap subprocess_map;
+
+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")) {
+ *supported_capabilities |= ODB_HELPER_CAP_GET;
+ } else if (!strcmp(cap_name, "put")) {
+ *supported_capabilities |= ODB_HELPER_CAP_PUT;
+ } 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);
+}
+
+static int start_read_object_fn(struct subprocess_entry *subprocess)
+{
+ int err;
+ struct read_object_process *entry = (struct read_object_process
*)subprocess;
+ struct child_process *process = &subprocess->process;
+ char *cap_buf;
+
+ sigchain_push(SIGPIPE, SIG_IGN);
+
+ err = packet_writel(process->in, "git-read-object-client", "version=1",
NULL);
+ if (err)
+ goto done;
+
+ err = strcmp(packet_read_line(process->out, NULL),
"git-read-object-server");
+ if (err) {
+ error("external process '%s' does not support read-object
protocol version 1", subprocess->cmd);
+ goto done;
+ }
+ err = strcmp(packet_read_line(process->out, NULL), "version=1");
+ if (err)
+ goto done;
+ err = packet_read_line(process->out, NULL) != NULL;
+ if (err)
+ goto done;
+
+ err = packet_writel(process->in, "capability=get", NULL);
+ if (err)
+ goto done;
+
+ while ((cap_buf = packet_read_line(process->out, NULL)))
+ parse_capabilities(cap_buf, &entry->supported_capabilities,
subprocess->cmd);
+
+done:
+ sigchain_pop(SIGPIPE);
+
+ return err;
+}
+
+static struct read_object_process *launch_read_object_process(const char *cmd)
+{
+ struct read_object_process *entry;
+
+ if (!subprocess_map_initialized) {
+ subprocess_map_initialized = 1;
+ hashmap_init(&subprocess_map, (hashmap_cmp_fn) cmd2process_cmp,
0);
+ entry = NULL;
+ } else {
+ entry = (struct read_object_process
*)subprocess_find_entry(&subprocess_map, cmd);
+ }
+
+ fflush(NULL);
+
+ if (!entry) {
+ entry = xmalloc(sizeof(*entry));
+ entry->supported_capabilities = 0;
+
+ if (subprocess_start(&subprocess_map, &entry->subprocess, cmd,
start_read_object_fn)) {
+ free(entry);
+ return 0;
+ }
+ }
+
+ return entry;
+}
+
+static int check_object_process_error(int err,
+ const char *status,
+ struct read_object_process *entry,
+ const char *cmd,
+ unsigned int capability)
+{
+ if (!err)
+ return;
+
+ if (!strcmp(status, "error")) {
+ /* The process signaled a problem with the file. */
+ } else if (!strcmp(status, "notfound")) {
+ /* Object was not found */
+ err = -1;
+ } else if (!strcmp(status, "abort")) {
+ /*
+ * The process signaled a permanent problem. Don't try to read
+ * objects with the same command for the lifetime of the current
+ * Git process.
+ */
+ if (capability)
+ entry->supported_capabilities &= ~capability;
+ } else {
+ /*
+ * Something went wrong with the read-object process.
+ * Force shutdown and restart if needed.
+ */
+ error("external object process '%s' failed", cmd);
+ subprocess_stop(&subprocess_map, &entry->subprocess);
+ free(entry);
+ }
+
+ return err;
+}
+
+static int read_object_process(const unsigned char *sha1)
+{
+ int err;
+ struct read_object_process *entry;
+ struct child_process *process;
+ struct strbuf status = STRBUF_INIT;
+ const char *cmd = "read-object";
+ uint64_t start;
+
+ start = getnanotime();
+
+ entry = launch_read_object_process(cmd);
+ process = &entry->subprocess.process;
+
+ if (!(ODB_HELPER_CAP_GET & entry->supported_capabilities))
+ return -1;
+
+ sigchain_push(SIGPIPE, SIG_IGN);
+
+ err = packet_write_fmt_gently(process->in, "command=get\n");
+ if (err)
+ goto done;
+
+ err = packet_write_fmt_gently(process->in, "sha1=%s\n",
sha1_to_hex(sha1));
+ if (err)
+ goto done;
+
+ err = packet_flush_gently(process->in);
+ if (err)
+ goto done;
+
+ subprocess_read_status(process->out, &status);
+ err = strcmp(status.buf, "success");
+
+done:
+ sigchain_pop(SIGPIPE);
+
+ err = check_object_process_error(err, status.buf, entry, cmd,
ODB_HELPER_CAP_GET);
+
+ trace_performance_since(start, "read_object_process");
+
+ return err;
+}
struct odb_helper *odb_helper_new(const char *name, int namelen)
{
@@ -350,20 +531,21 @@ static int odb_helper_fetch_git_object(struct odb_helper
*o,
int odb_helper_fault_in_object(struct odb_helper *o,
const unsigned char *sha1)
{
- struct odb_helper_object *obj;
- struct odb_helper_cmd cmd;
+ struct odb_helper_object *obj = odb_helper_lookup(o, sha1);
- obj = odb_helper_lookup(o, sha1);
if (!obj)
return -1;
- if (odb_helper_start(o, &cmd, 0, "get %s", sha1_to_hex(sha1)) < 0)
- return -1;
-
- if (odb_helper_finish(o, &cmd))
- return -1;
-
- return 0;
+ if (o->script_mode) {
+ struct odb_helper_cmd cmd;
+ if (odb_helper_start(o, &cmd, 0, "get %s", sha1_to_hex(sha1)) <
0)
+ return -1;
+ if (odb_helper_finish(o, &cmd))
+ return -1;
+ return 0;
+ } else {
+ return read_object_process(sha1);
+ }
}
int odb_helper_fetch_object(struct odb_helper *o,
diff --git a/odb-helper.h b/odb-helper.h
index 44c98bbf56..b23544aa4a 100644
--- a/odb-helper.h
+++ b/odb-helper.h
@@ -9,11 +9,16 @@ enum odb_helper_fetch_kind {
ODB_FETCH_KIND_FAULT_IN
};
+#define ODB_HELPER_CAP_GET (1u<<0)
+#define ODB_HELPER_CAP_PUT (1u<<1)
+#define ODB_HELPER_CAP_HAVE (1u<<2)
+
struct odb_helper {
const char *name;
const char *cmd;
enum odb_helper_fetch_kind fetch_kind;
int script_mode;
+ unsigned int supported_capabilities;
struct odb_helper_object {
unsigned char sha1[20];
diff --git a/sha1_file.c b/sha1_file.c
index 9d8e37432e..38a0404506 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -698,7 +698,17 @@ int check_and_freshen_file(const char *fn, int freshen)
static int check_and_freshen_local(const unsigned char *sha1, int freshen)
{
- return check_and_freshen_file(sha1_file_name(sha1), freshen);
+ int ret;
+ int tried_hook = 0;
+
+retry:
+ ret = check_and_freshen_file(sha1_file_name(sha1), freshen);
+ if (!ret && !tried_hook) {
+ tried_hook = 1;
+ if (!external_odb_fault_in_object(sha1))
+ goto retry;
+ }
+ return ret;
}
static int check_and_freshen_nonlocal(const unsigned char *sha1, int freshen)
@@ -3000,7 +3010,9 @@ int sha1_object_info_extended(const unsigned char *sha1,
struct object_info *oi,
int rtype;
enum object_type real_type;
const unsigned char *real = lookup_replace_object_extended(sha1, flags);
+ int tried_hook = 0;
+retry:
co = find_cached_object(real);
if (co) {
if (oi->typep)
@@ -3026,8 +3038,14 @@ int sha1_object_info_extended(const unsigned char *sha1,
struct object_info *oi,
/* Not a loose object; someone else may have just packed it. */
reprepare_packed_git();
- if (!find_pack_entry(real, &e))
+ if (!find_pack_entry(real, &e)) {
+ if (!tried_hook) {
+ tried_hook = 1;
+ if (!external_odb_fault_in_object(sha1))
+ goto retry;
+ }
return -1;
+ }
}
/*
@@ -3121,7 +3139,9 @@ static void *read_object(const unsigned char *sha1, enum
object_type *type,
unsigned long mapsize;
void *map, *buf;
struct cached_object *co;
+ int tried_hook = 0;
+retry:
co = find_cached_object(sha1);
if (co) {
*type = co->type;
@@ -3139,7 +3159,14 @@ static void *read_object(const unsigned char *sha1, enum
object_type *type,
return buf;
}
reprepare_packed_git();
- return read_packed_sha1(sha1, type, size);
+ buf = read_packed_sha1(sha1, type, size);
+ if (!buf && !tried_hook) {
+ tried_hook = 1;
+ if (!external_odb_fault_in_object(sha1))
+ goto retry;
+ }
+
+ return buf;
}
/*
--
2.13.1.565.gbfcd7a9048
