check_everything_connected(): libify

Extract the helper function and the type definition of the iterator
function it uses out of builtin/fetch.c into a separate source and a
header file.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

4 files changed, 85 insertions, 65 deletions

diff --git a/Makefile b/Makefile
index e40ac0c7f5..23d7658924 100644
--- a/Makefile
+++ b/Makefile
@@ -511,6 +511,7 @@ LIB_H += compat/win32/pthread.h
 LIB_H += compat/win32/syslog.h
 LIB_H += compat/win32/sys/poll.h
 LIB_H += compat/win32/dirent.h
+LIB_H += connected.h
 LIB_H += csum-file.h
 LIB_H += decorate.h
 LIB_H += delta.h
@@ -587,6 +588,7 @@ LIB_OBJS += combine-diff.o
 LIB_OBJS += commit.o
 LIB_OBJS += config.o
 LIB_OBJS += connect.o
+LIB_OBJS += connected.o
 LIB_OBJS += convert.o
 LIB_OBJS += copy.o
 LIB_OBJS += csum-file.o
diff --git a/builtin/fetch.c b/builtin/fetch.c
index 0ef912eac0..ffda063d91 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -13,6 +13,7 @@
 #include "sigchain.h"
 #include "transport.h"
 #include "submodule.h"
+#include "connected.h"
 
 static const char * const builtin_fetch_usage[] = {
 	"git fetch [<options>] [<repository> [<refspec>...]]",
@@ -345,71 +346,6 @@ static int update_local_ref(struct ref *ref,
 	}
 }
 
-/*
- * Take callback data, and return next object name in the buffer.
- * When called after returning the name for the last object, return -1
- * to signal EOF, otherwise return 0.
- */
-typedef int (*sha1_iterate_fn)(void *, unsigned char [20]);
-
-/*
- * If we feed all the commits we want to verify to this command
- *
- *  $ git rev-list --verify-objects --stdin --not --all
- *
- * and if it does not error out, that means everything reachable from
- * these commits locally exists and is connected to some of our
- * existing refs.
- *
- * Returns 0 if everything is connected, non-zero otherwise.
- */
-static int check_everything_connected(sha1_iterate_fn fn, int quiet, void *cb_data)
-{
-	struct child_process rev_list;
-	const char *argv[] = {"rev-list", "--verify-objects",
-			      "--stdin", "--not", "--all", NULL, NULL};
-	char commit[41];
-	unsigned char sha1[20];
-	int err = 0;
-
-	if (fn(cb_data, sha1))
-		return err;
-
-	if (quiet)
-		argv[5] = "--quiet";
-
-	memset(&rev_list, 0, sizeof(rev_list));
-	rev_list.argv = argv;
-	rev_list.git_cmd = 1;
-	rev_list.in = -1;
-	rev_list.no_stdout = 1;
-	rev_list.no_stderr = quiet;
-	if (start_command(&rev_list))
-		return error(_("Could not run 'git rev-list'"));
-
-	sigchain_push(SIGPIPE, SIG_IGN);
-
-	commit[40] = '\n';
-	do {
-		memcpy(commit, sha1_to_hex(sha1), 40);
-		if (write_in_full(rev_list.in, commit, 41) < 0) {
-			if (errno != EPIPE && errno != EINVAL)
-				error(_("failed write to rev-list: %s"),
-				      strerror(errno));
-			err = -1;
-			break;
-		}
-	} while (!fn(cb_data, sha1));
-
-	if (close(rev_list.in)) {
-		error(_("failed to close rev-list's stdin: %s"), strerror(errno));
-		err = -1;
-	}
-
-	sigchain_pop(SIGPIPE);
-	return finish_command(&rev_list) || err;
-}
-
 static int iterate_ref_map(void *cb_data, unsigned char sha1[20])
 {
 	struct ref **rm = cb_data;
diff --git a/connected.c b/connected.c
new file mode 100644
index 0000000000..d7624230d4
--- /dev/null
+++ b/connected.c
@@ -0,0 +1,62 @@
+#include "cache.h"
+#include "run-command.h"
+#include "sigchain.h"
+#include "connected.h"
+
+/*
+ * If we feed all the commits we want to verify to this command
+ *
+ *  $ git rev-list --verify-objects --stdin --not --all
+ *
+ * and if it does not error out, that means everything reachable from
+ * these commits locally exists and is connected to some of our
+ * existing refs.
+ *
+ * Returns 0 if everything is connected, non-zero otherwise.
+ */
+int check_everything_connected(sha1_iterate_fn fn, int quiet, void *cb_data)
+{
+	struct child_process rev_list;
+	const char *argv[] = {"rev-list", "--verify-objects",
+			      "--stdin", "--not", "--all", NULL, NULL};
+	char commit[41];
+	unsigned char sha1[20];
+	int err = 0;
+
+	if (fn(cb_data, sha1))
+		return err;
+
+	if (quiet)
+		argv[5] = "--quiet";
+
+	memset(&rev_list, 0, sizeof(rev_list));
+	rev_list.argv = argv;
+	rev_list.git_cmd = 1;
+	rev_list.in = -1;
+	rev_list.no_stdout = 1;
+	rev_list.no_stderr = quiet;
+	if (start_command(&rev_list))
+		return error(_("Could not run 'git rev-list'"));
+
+	sigchain_push(SIGPIPE, SIG_IGN);
+
+	commit[40] = '\n';
+	do {
+		memcpy(commit, sha1_to_hex(sha1), 40);
+		if (write_in_full(rev_list.in, commit, 41) < 0) {
+			if (errno != EPIPE && errno != EINVAL)
+				error(_("failed write to rev-list: %s"),
+				      strerror(errno));
+			err = -1;
+			break;
+		}
+	} while (!fn(cb_data, sha1));
+
+	if (close(rev_list.in)) {
+		error(_("failed to close rev-list's stdin: %s"), strerror(errno));
+		err = -1;
+	}
+
+	sigchain_pop(SIGPIPE);
+	return finish_command(&rev_list) || err;
+}
diff --git a/connected.h b/connected.h
new file mode 100644
index 0000000000..7e4585a6cb
--- /dev/null
+++ b/connected.h
@@ -0,0 +1,20 @@
+#ifndef CONNECTED_H
+#define CONNECTED_H
+
+/*
+ * Take callback data, and return next object name in the buffer.
+ * When called after returning the name for the last object, return -1
+ * to signal EOF, otherwise return 0.
+ */
+typedef int (*sha1_iterate_fn)(void *, unsigned char [20]);
+
+/*
+ * Make sure that our object store has all the commits necessary to
+ * connect the ancestry chain to some of our existing refs, and all
+ * the trees and blobs that these commits use.
+ *
+ * Return 0 if Ok, non zero otherwise (i.e. some missing objects)
+ */
+extern int check_everything_connected(sha1_iterate_fn, int quiet, void *cb_data);
+
+#endif /* CONNECTED_H */