1 files changed, 40 insertions, 16 deletions

diff --git a/progress.c b/progress.c
index a4da26c2aa..a2e8cf64a8 100644
--- a/progress.c
+++ b/progress.c
@@ -35,6 +35,7 @@ struct progress {
 	uint64_t total;
 	unsigned last_percent;
 	unsigned delay;
+	unsigned sparse;
 	struct throughput *throughput;
 	uint64_t start_ns;
 	struct strbuf counters_sb;
@@ -166,12 +167,10 @@ void display_throughput(struct progress *progress, uint64_t total)
 	now_ns = getnanotime();
 
 	if (!tp) {
-		progress->throughput = tp = calloc(1, sizeof(*tp));
-		if (tp) {
-			tp->prev_total = tp->curr_total = total;
-			tp->prev_ns = now_ns;
-			strbuf_init(&tp->display, 0);
-		}
+		progress->throughput = tp = xcalloc(1, sizeof(*tp));
+		tp->prev_total = tp->curr_total = total;
+		tp->prev_ns = now_ns;
+		strbuf_init(&tp->display, 0);
 		return;
 	}
 	tp->curr_total = total;
@@ -222,20 +221,15 @@ void display_progress(struct progress *progress, uint64_t n)
 }
 
 static struct progress *start_progress_delay(const char *title, uint64_t total,
-					     unsigned delay)
+					     unsigned delay, unsigned sparse)
 {
-	struct progress *progress = malloc(sizeof(*progress));
-	if (!progress) {
-		/* unlikely, but here's a good fallback */
-		fprintf(stderr, "%s...\n", title);
-		fflush(stderr);
-		return NULL;
-	}
+	struct progress *progress = xmalloc(sizeof(*progress));
 	progress->title = title;
 	progress->total = total;
 	progress->last_value = -1;
 	progress->last_percent = -1;
 	progress->delay = delay;
+	progress->sparse = sparse;
 	progress->throughput = NULL;
 	progress->start_ns = getnanotime();
 	strbuf_init(&progress->counters_sb, 0);
@@ -247,16 +241,46 @@ static struct progress *start_progress_delay(const char *title, uint64_t total,
 
 struct progress *start_delayed_progress(const char *title, uint64_t total)
 {
-	return start_progress_delay(title, total, 2);
+	return start_progress_delay(title, total, 2, 0);
 }
 
 struct progress *start_progress(const char *title, uint64_t total)
 {
-	return start_progress_delay(title, total, 0);
+	return start_progress_delay(title, total, 0, 0);
+}
+
+/*
+ * Here "sparse" means that the caller might use some sampling criteria to
+ * decide when to call display_progress() rather than calling it for every
+ * integer value in[0 .. total).  In particular, the caller might not call
+ * display_progress() for the last value in the range.
+ *
+ * When "sparse" is set, stop_progress() will automatically force the done
+ * message to show 100%.
+ */
+struct progress *start_sparse_progress(const char *title, uint64_t total)
+{
+	return start_progress_delay(title, total, 0, 1);
+}
+
+struct progress *start_delayed_sparse_progress(const char *title,
+					       uint64_t total)
+{
+	return start_progress_delay(title, total, 2, 1);
+}
+
+static void finish_if_sparse(struct progress *progress)
+{
+	if (progress &&
+	    progress->sparse &&
+	    progress->last_value != progress->total)
+		display_progress(progress, progress->total);
 }
 
 void stop_progress(struct progress **p_progress)
 {
+	finish_if_sparse(*p_progress);
+
 	stop_progress_msg(p_progress, _("done"));
 }