[PATCH] send pack check for failure to send revisions list

[Andy Whitcroft <apw@shadowen.org>]

When passing the revisions list to pack-objects we do not check for
errors nor short writes.  Introduce a new write_in_full which will
handle short writes and report errors to the caller.  Use this to
short cut the send on failure, allowing us to wait for and report
the child in case the failure is its fault.

Signed-off-by: Andy Whitcroft <apw@shadowen.org>
---
diff --git a/send-pack.c b/send-pack.c
index eaa6efb..c195d08 100644
--- a/send-pack.c
+++ b/send-pack.c
@@ -65,12 +65,16 @@ static int pack_objects(int fd, struct ref *refs)
 			memcpy(buf + 1, sha1_to_hex(refs->old_sha1), 40);
 			buf[0] = '^';
 			buf[41] = '\n';
-			write(pipe_fd[1], buf, 42);
+			if (!write_in_full(pipe_fd[1], buf, 42,
+						"send-pack: send refs"))
+				break;
 		}
 		if (!is_null_sha1(refs->new_sha1)) {
 			memcpy(buf, sha1_to_hex(refs->new_sha1), 40);
 			buf[40] = '\n';
-			write(pipe_fd[1], buf, 41);
+			if (!write_in_full(pipe_fd[1], buf, 41,
+						"send-pack: send refs"))
+				break;
 		}
 		refs = refs->next;
 	}
diff --git a/write_or_die.c b/write_or_die.c
index 8cf6486..6db1d31 100644
--- a/write_or_die.c
+++ b/write_or_die.c
@@ -59,3 +59,26 @@ int write_or_whine(int fd, const void *buf, size_t count, const char *msg)
 
 	return 1;
 }
+
+int write_in_full(int fd, const void *buf, size_t count, const char *msg)
+{
+	const char *p = buf;
+	ssize_t written;
+
+	while (count > 0) {
+		written = xwrite(fd, p, count);
+		if (written == 0) {
+			fprintf(stderr, "%s: disk full?\n", msg);
+			return 0;
+		}
+		else if (written < 0) {
+			fprintf(stderr, "%s: write error (%s)\n",
+				msg, strerror(errno));
+			return 0;
+		}
+		count -= written;
+		p += written;
+	}
+
+	return 1;
+}