rev-list: add optional progress reporting

It's easy to ask rev-list to do a traversal that may takes
many seconds (e.g., by calling "--objects --all"). In theory
you can monitor its progress by the output you get to
stdout, but this isn't always easy.

Some operations, like "--count", don't make any output until
the end.

And some callers, like check_everything_connected(), are
using it just for the error-checking of the traversal, and
throw away stdout entirely.

This patch adds a "--progress" option which can be used to
give some eye-candy for a user waiting for a long traversal.
This is just a rev-list option and not a regular traversal
option, because it needs cooperation from the callbacks in
builtin/rev-list.c to do the actual count.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/Documentation/rev-list-options.txt b/Documentation/rev-list-options.txt
index c5bd21812d63418e9011c32c96f5adc9bc193c90..f39cb6d4f56e55da0c38841c9da0346b12b841a0 100644 (file)
--- a/Documentation/rev-list-options.txt
+++ b/Documentation/rev-list-options.txt
@@ -274,6 +274,10 @@ ifdef::git-rev-list[]
        Try to speed up the traversal using the pack bitmap index (if
        one is available). Note that when traversing with `--objects`,
        trees and blobs will not have their associated path printed.
+
+--progress=<header>::
+       Show progress reports on stderr as objects are considered. The
+       `<header>` text will be printed with each progress update.
 endif::git-rev-list[]
 
 --

diff --git a/builtin/rev-list.c b/builtin/rev-list.c
index b82bcc3436014183084f48575f6c4568a0a94b5c..0ba82b1635b6380d9a7d9fd9a31471b8c8ac9f20 100644 (file)
--- a/builtin/rev-list.c
+++ b/builtin/rev-list.c
@@ -9,6 +9,7 @@
 #include "log-tree.h"
 #include "graph.h"
 #include "bisect.h"
+#include "progress.h"
 
 static const char rev_list_usage[] =
 "git rev-list [OPTION] <commit-id>... [ -- paths... ]\n"
@@ -49,12 +50,17 @@ static const char rev_list_usage[] =
 "    --bisect-all"
 ;
 
+static struct progress *progress;
+static unsigned progress_counter;
+
 static void finish_commit(struct commit *commit, void *data);
 static void show_commit(struct commit *commit, void *data)
 {
        struct rev_list_info *info = data;
        struct rev_info *revs = info->revs;
 
+       display_progress(progress, ++progress_counter);
+
        if (info->flags & REV_LIST_QUIET) {
                finish_commit(commit, data);
                return;
@@ -190,6 +196,7 @@ static void show_object(struct object *obj, const char *name, void *cb_data)
 {
        struct rev_list_info *info = cb_data;
        finish_object(obj, name, cb_data);
+       display_progress(progress, ++progress_counter);
        if (info->flags & REV_LIST_QUIET)
                return;
        show_object_with_name(stdout, obj, name);
@@ -276,6 +283,7 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
        int bisect_show_vars = 0;
        int bisect_find_all = 0;
        int use_bitmap_index = 0;
+       const char *show_progress = NULL;
 
        git_config(git_default_config, NULL);
        init_revisions(&revs, prefix);
@@ -325,6 +333,10 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
                        test_bitmap_walk(&revs);
                        return 0;
                }
+               if (skip_prefix(arg, "--progress=", &arg)) {
+                       show_progress = arg;
+                       continue;
+               }
                usage(rev_list_usage);
 
        }
@@ -355,6 +367,9 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
        if (bisect_list)
                revs.limited = 1;
 
+       if (show_progress)
+               progress = start_progress_delay(show_progress, 0, 0, 2);
+
        if (use_bitmap_index && !revs.prune) {
                if (revs.count && !revs.left_right && !revs.cherry_mark) {
                        uint32_t commit_count;
@@ -392,6 +407,8 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
 
        traverse_commit_list(&revs, show_commit, show_object, &info);
 
+       stop_progress(&progress);
+
        if (revs.count) {
                if (revs.left_right && revs.cherry_mark)
                        printf("%d\t%d\t%d\n", revs.count_left, revs.count_right, revs.count_same);