Move read_in_full() and write_in_full() to wrapper.c

A few compat/* layer functions call these functions, but we would really
want to keep them thin, without depending too much on the libgit proper.

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

1 files changed, 38 insertions, 0 deletions

diff --git a/wrapper.c b/wrapper.c
index 4e04f7661b..93562f03ee 100644
--- a/wrapper.c
+++ b/wrapper.c
@@ -133,6 +133,44 @@ ssize_t xwrite(int fd, const void *buf, size_t len)
 	}
 }
 
+ssize_t read_in_full(int fd, void *buf, size_t count)
+{
+	char *p = buf;
+	ssize_t total = 0;
+
+	while (count > 0) {
+		ssize_t loaded = xread(fd, p, count);
+		if (loaded <= 0)
+			return total ? total : loaded;
+		count -= loaded;
+		p += loaded;
+		total += loaded;
+	}
+
+	return total;
+}
+
+ssize_t write_in_full(int fd, const void *buf, size_t count)
+{
+	const char *p = buf;
+	ssize_t total = 0;
+
+	while (count > 0) {
+		ssize_t written = xwrite(fd, p, count);
+		if (written < 0)
+			return -1;
+		if (!written) {
+			errno = ENOSPC;
+			return -1;
+		}
+		count -= written;
+		p += written;
+		total += written;
+	}
+
+	return total;
+}
+
 int xdup(int fd)
 {
 	int ret = dup(fd);