This adds support for the script command mode where
an helper script or command is called to retrieve or
manage objects.
This implements the 'have' and 'get_git_obj'
instructions for the script mode.
Signed-off-by: Christian Couder <chrisc...@tuxfamily.org>
---
external-odb.c | 55 +++++++++-
external-odb.h | 1 +
odb-helper.c | 218 +++++++++++++++++++++++++++++++++++++++-
odb-helper.h | 4 +
sha1_file.c | 12 ++-
t/t0500-external-odb.sh | 44 ++++++++
6 files changed, 331 insertions(+), 3 deletions(-)
create mode 100755 t/t0500-external-odb.sh
diff --git a/external-odb.c b/external-odb.c
index 82ac80aa04..ec1ec82dd9 100644
--- a/external-odb.c
+++ b/external-odb.c
@@ -33,8 +33,14 @@ static int external_odb_config(const char *var, const char
*value, void *data)
o = find_or_create_helper(name, namelen);
- if (!strcmp(subkey, "promisorremote"))
+ if (!strcmp(subkey, "promisorremote")) {
+ o->type = ODB_HELPER_GIT_REMOTE;
return git_config_string(&o->dealer, var, value);
+ }
+ if (!strcmp(subkey, "scriptcommand")) {
+ o->type = ODB_HELPER_SCRIPT_CMD;
+ return git_config_string(&o->dealer, var, value);
+ }
return 0;
}
@@ -100,6 +106,53 @@ int external_odb_has_object(const unsigned char *sha1)
return 0;
}
+int external_odb_get_object(const unsigned char *sha1)
+{
+ struct odb_helper *o;
+ struct strbuf pathbuf = STRBUF_INIT;
+
+ if (!external_odb_has_object(sha1))
+ return -1;
+
+ sha1_file_name_alt(&pathbuf, external_odb_root(), sha1);
+ safe_create_leading_directories_const(pathbuf.buf);
+ prepare_external_alt_odb();
+
+ for (o = helpers; o; o = o->next) {
+ struct strbuf tmpfile = STRBUF_INIT;
+ int ret;
+ int fd;
+
+ if (!odb_helper_has_object(o, sha1))
+ continue;
+
+ fd = create_object_tmpfile(&tmpfile, pathbuf.buf);
+ if (fd < 0) {
+ strbuf_release(&tmpfile);
+ strbuf_release(&pathbuf);
+ return -1;
+ }
+
+ if (odb_helper_get_object(o, sha1, fd) < 0) {
+ close(fd);
+ unlink(tmpfile.buf);
+ strbuf_release(&tmpfile);
+ continue;
+ }
+
+ close_sha1_file(fd);
+ ret = finalize_object_file(tmpfile.buf, pathbuf.buf);
+ strbuf_release(&tmpfile);
+ strbuf_release(&pathbuf);
+ if (!ret)
+ return 0;
+ }
+
+ strbuf_release(&pathbuf);
+
+ return -1;
+}
+
int external_odb_get_direct(const unsigned char *sha1)
{
struct odb_helper *o;
diff --git a/external-odb.h b/external-odb.h
index 254070994a..c5ac071995 100644
--- a/external-odb.h
+++ b/external-odb.h
@@ -15,6 +15,7 @@ extern struct odb_helper *find_odb_helper(const char *dealer,
enum odb_helper_type type);
extern const char *external_odb_root(void);
extern int external_odb_has_object(const unsigned char *sha1);
+extern int external_odb_get_object(const unsigned char *sha1);
extern int external_odb_get_direct(const unsigned char *sha1);
#endif /* EXTERNAL_ODB_H */
diff --git a/odb-helper.c b/odb-helper.c
index c6127ce81f..677ea850a5 100644
--- a/odb-helper.c
+++ b/odb-helper.c
@@ -21,13 +21,124 @@ struct odb_helper_cmd {
struct child_process child;
};
+/*
+ * Callers are responsible to ensure that the result of vaddf(fmt, ap)
+ * is properly shell-quoted.
+ */
+static void prepare_helper_command(struct argv_array *argv, const char *cmd,
+ const char *fmt, va_list ap)
+{
+ struct strbuf buf = STRBUF_INIT;
+
+ strbuf_addstr(&buf, cmd);
+ strbuf_addch(&buf, ' ');
+ strbuf_vaddf(&buf, fmt, ap);
+
+ argv_array_push(argv, buf.buf);
+ strbuf_release(&buf);
+}
+
+__attribute__((format (printf,3,4)))
+static int odb_helper_start(struct odb_helper *o,
+ struct odb_helper_cmd *cmd,
+ const char *fmt, ...)
+{
+ va_list ap;
+
+ memset(cmd, 0, sizeof(*cmd));
+ argv_array_init(&cmd->argv);
+
+ if (!o->dealer)
+ return -1;
+
+ va_start(ap, fmt);
+ prepare_helper_command(&cmd->argv, o->dealer, fmt, ap);
+ va_end(ap);
+
+ cmd->child.argv = cmd->argv.argv;
+ cmd->child.use_shell = 1;
+ cmd->child.no_stdin = 1;
+ cmd->child.out = -1;
+
+ if (start_command(&cmd->child) < 0) {
+ argv_array_clear(&cmd->argv);
+ return -1;
+ }
+
+ return 0;
+}
+
+static int odb_helper_finish(struct odb_helper *o,
+ struct odb_helper_cmd *cmd)
+{
+ int ret = finish_command(&cmd->child);
+ argv_array_clear(&cmd->argv);
+ if (ret) {
+ warning("odb helper '%s' reported failure", o->name);
+ return -1;
+ }
+ return 0;
+}
+
+static int parse_object_line(struct odb_helper_object *o, const char *line)
+{
+ char *end;
+ if (get_oid_hex(line, &o->oid) < 0)
+ return -1;
+
+ line += 40;
+ if (*line++ != ' ')
+ return -1;
+
+ o->size = strtoul(line, &end, 10);
+ if (line == end || *end++ != ' ')
+ return -1;
+
+ o->type = type_from_string(end);
+ return 0;
+}
+
+static int add_have_entry(struct odb_helper *o, const char *line)
+{
+ ALLOC_GROW(o->have, o->have_nr+1, o->have_alloc);
+ if (parse_object_line(&o->have[o->have_nr], line) < 0) {
+ warning("bad 'have' input from odb helper '%s': %s",
+ o->name, line);
+ return 1;
+ }
+ o->have_nr++;
+ return 0;
+}
+
+static int odb_helper_object_cmp(const void *va, const void *vb)
+{
+ const struct odb_helper_object *a = va, *b = vb;
+ return oidcmp(&a->oid, &b->oid);
+}
+
static void odb_helper_load_have(struct odb_helper *o)
{
+ struct odb_helper_cmd cmd;
+ FILE *fh;
+ struct strbuf line = STRBUF_INIT;
+
if (o->have_valid)
return;
o->have_valid = 1;
- /* TODO */
+ if (odb_helper_start(o, &cmd, "have") < 0)
+ return;
+
+ fh = xfdopen(cmd.child.out, "r");
+ while (strbuf_getline(&line, fh) != EOF)
+ if (add_have_entry(o, line.buf))
+ break;
+
+ strbuf_release(&line);
+ fclose(fh);
+ odb_helper_finish(o, &cmd);
+
+ qsort(o->have, o->have_nr, sizeof(*o->have), odb_helper_object_cmp);
}
static const unsigned char *have_sha1_access(size_t index, void *table)
@@ -53,6 +164,111 @@ int odb_helper_has_object(struct odb_helper *o, const
unsigned char *sha1)
return !!odb_helper_lookup(o, sha1);
}
+int odb_helper_get_object(struct odb_helper *o, const unsigned char *sha1,
+ int fd)
+{
+ struct odb_helper_object *obj;
+ struct odb_helper_cmd cmd;
+ unsigned long total_got;
+ git_zstream stream;
+ int zret = Z_STREAM_END;
+ git_SHA_CTX hash;
+ unsigned char real_sha1[20];
+ struct strbuf header = STRBUF_INIT;
+ unsigned long hdr_size;
+
+ obj = odb_helper_lookup(o, sha1);
+ if (!obj)
+ return -1;
+
+ if (odb_helper_start(o, &cmd, "get_git_obj %s", sha1_to_hex(sha1)) < 0)
+ return -1;
+
+ memset(&stream, 0, sizeof(stream));
+ git_inflate_init(&stream);
+ git_SHA1_Init(&hash);
+ total_got = 0;
+
+ for (;;) {
+ unsigned char buf[4096];
+ int r;
+
+ r = xread(cmd.child.out, buf, sizeof(buf));
+ if (r < 0) {
+ error("unable to read from odb helper '%s': %s",
+ o->name, strerror(errno));
+ close(cmd.child.out);
+ odb_helper_finish(o, &cmd);
+ git_inflate_end(&stream);
+ return -1;
+ }
+ if (r == 0)
+ break;
+
+ write_or_die(fd, buf, r);
+
+ stream.next_in = buf;
+ stream.avail_in = r;
+ do {
+ unsigned char inflated[4096];
+ unsigned long got;
+
+ stream.next_out = inflated;
+ stream.avail_out = sizeof(inflated);
+ zret = git_inflate(&stream, Z_SYNC_FLUSH);
+ got = sizeof(inflated) - stream.avail_out;
+
+ git_SHA1_Update(&hash, inflated, got);
+ /* skip header when counting size */
+ if (!total_got) {
+ const unsigned char *p = memchr(inflated, '\0',
got);
+ if (p) {
+ unsigned long hdr_last = p - inflated +
1;
+ strbuf_add(&header, inflated, hdr_last);
+ got -= hdr_last;
+ } else {
+ strbuf_add(&header, inflated, got);
+ got = 0;
+ }
+ }
+ total_got += got;
+ } while (stream.avail_in && zret == Z_OK);
+ }
+
+ close(cmd.child.out);
+ git_inflate_end(&stream);
+ git_SHA1_Final(real_sha1, &hash);
+ if (odb_helper_finish(o, &cmd))
+ return -1;
+ if (zret != Z_STREAM_END) {
+ warning("bad zlib data from odb helper '%s' for %s",
+ o->name, sha1_to_hex(sha1));
+ return -1;
+ }
+ if (total_got != obj->size) {
+ warning("size mismatch from odb helper '%s' for %s (%lu !=
%lu)",
+ o->name, sha1_to_hex(sha1), total_got, obj->size);
+ return -1;
+ }
+ if (hashcmp(real_sha1, sha1)) {
+ warning("sha1 mismatch from odb helper '%s' for %s (got %s)",
+ o->name, sha1_to_hex(sha1), sha1_to_hex(real_sha1));
+ return -1;
+ }
+ if (parse_sha1_header(header.buf, &hdr_size) < 0) {
+ warning("could not parse header from odb helper '%s' for %s",
+ o->name, sha1_to_hex(sha1));
+ return -1;
+ }
+ if (total_got != hdr_size) {
+ warning("size mismatch from odb helper '%s' for %s (%lu !=
%lu)",
+ o->name, sha1_to_hex(sha1), total_got, hdr_size);
+ return -1;
+ }
+
+ return 0;
+}
+
int odb_helper_get_direct(struct odb_helper *o,
const unsigned char *sha1)
{
diff --git a/odb-helper.h b/odb-helper.h
index d4b968693f..819182f76a 100644
--- a/odb-helper.h
+++ b/odb-helper.h
@@ -23,6 +23,10 @@ struct odb_helper {
extern struct odb_helper *odb_helper_new(const char *name, int namelen);
extern int odb_helper_has_object(struct odb_helper *o,
const unsigned char *sha1);
+extern int odb_helper_get_object(struct odb_helper *o,
+ const unsigned char *sha1,
+ int fd);
extern int odb_helper_get_direct(struct odb_helper *o,
const unsigned char *sha1);
+
#endif /* ODB_HELPER_H */
diff --git a/sha1_file.c b/sha1_file.c
index c460eb2658..847883f261 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -907,6 +907,9 @@ static int stat_sha1_file(const unsigned char *sha1, struct
stat *st,
return 0;
}
+ if (!external_odb_get_object(sha1) && !lstat(*path, st))
+ return 0;
+
return -1;
}
@@ -946,7 +949,14 @@ static int open_sha1_file(const unsigned char *sha1, const
char **path)
if (fd >= 0)
return fd;
- return open_sha1_file_alt(sha1, path);
+ fd = open_sha1_file_alt(sha1, path);
+ if (fd >= 0)
+ return fd;
+
+ if (!external_odb_get_object(sha1))
+ fd = open_sha1_file_alt(sha1, path);
+
+ return fd;
}
/*
diff --git a/t/t0500-external-odb.sh b/t/t0500-external-odb.sh
new file mode 100755
index 0000000000..eaa3688a31
--- /dev/null
+++ b/t/t0500-external-odb.sh
@@ -0,0 +1,44 @@
+#!/bin/sh
+
+test_description='basic tests for external object databases'
+
+. ./test-lib.sh
+
+ALT_SOURCE="$PWD/alt-repo/.git"
+export ALT_SOURCE
+write_script odb-helper <<\EOF
+GIT_DIR=$ALT_SOURCE; export GIT_DIR
+case "$1" in
+have)
+ git cat-file --batch-check --batch-all-objects |
+ awk '{print $1 " " $3 " " $2}'
+ ;;
+get_git_obj)
+ cat "$GIT_DIR"/objects/$(echo $2 | sed 's#..#&/#')
+ ;;
+esac
+EOF
+HELPER="\"$PWD\"/odb-helper"
+
+test_expect_success 'setup alternate repo' '
+ git init alt-repo &&
+ test_commit -C alt-repo one &&
+ test_commit -C alt-repo two &&
+ alt_head=$(git -C alt-repo rev-parse HEAD)
+'
+
+test_expect_success 'alt objects are missing' '
+ test_must_fail git log --format=%s $alt_head
+'
+
+test_expect_success 'helper can retrieve alt objects' '
+ test_config odb.magic.scriptCommand "$HELPER" &&
+ cat >expect <<-\EOF &&
+ two
+ one
+ EOF
+ git log --format=%s $alt_head >actual &&
+ test_cmp expect actual
+'
+
+test_done
--
2.17.0.rc0.37.g8f476fabe9
