Add async cli_pull support

This is the big (and potentially controversial) one. It took a phone call to
explain to metze what is going on inside cli_pull_read_done, but I would really
like everybody to understand this function. It is a very good and reasonably
complex example of async programming. If we want more asynchronism in s3, this
is what we will have to deal with :-)

Make use of it in the smbclient "get" command.

Volker
(This used to be commit 844a163458c7585e4306a21ffdae5d08e03d6e4d)

1 files changed, 15 insertions, 27 deletions

diff --git a/source3/client/client.c b/source3/client/client.c
index f7ed33ad8a..1410fc2f33 100644
--- a/source3/client/client.c
+++ b/source3/client/client.c
@@ -964,12 +964,20 @@ static int cmd_echo(void)
  Get a file from rname to lname
 ****************************************************************************/
 
+static NTSTATUS writefile_sink(char *buf, size_t n, void *priv)
+{
+	int *pfd = (int *)priv;
+	if (writefile(*pfd, buf, n) == -1) {
+		return map_nt_error_from_unix(errno);
+	}
+	return NT_STATUS_OK;
+}
+
 static int do_get(const char *rname, const char *lname_in, bool reget)
 {
 	TALLOC_CTX *ctx = talloc_tos();
 	int handle = 0, fnum;
 	bool newhandle = false;
-	char *data = NULL;
 	struct timeval tp_start;
 	int read_size = io_bufsize;
 	uint16 attr;
@@ -980,6 +988,7 @@ static int do_get(const char *rname, const char *lname_in, bool reget)
 	struct cli_state *targetcli = NULL;
 	char *targetname = NULL;
 	char *lname = NULL;
+	NTSTATUS status;
 
 	lname = talloc_strdup(ctx, lname_in);
 	if (!lname) {
@@ -1038,36 +1047,15 @@ static int do_get(const char *rname, const char *lname_in, bool reget)
 	DEBUG(1,("getting file %s of size %.0f as %s ",
 		 rname, (double)size, lname));
 
-	if(!(data = (char *)SMB_MALLOC(read_size))) {
-		d_printf("malloc fail for size %d\n", read_size);
+	status = cli_pull(targetcli, fnum, start, size, 1024*1024,
+			  writefile_sink, (void *)&handle, &nread);
+	if (!NT_STATUS_IS_OK(status)) {
+		d_fprintf(stderr, "parallel_read returned %s\n",
+			  nt_errstr(status));
 		cli_close(targetcli, fnum);
 		return 1;
 	}
 
-	while (1) {
-		int n = cli_read(targetcli, fnum, data, nread + start, read_size);
-
-		if (n <= 0)
-			break;
-
-		if (writefile(handle,data, n) != n) {
-			d_printf("Error writing local file\n");
-			rc = 1;
-			break;
-		}
-
-		nread += n;
-	}
-
-	if (nread + start < size) {
-		DEBUG (0, ("Short read when getting file %s. Only got %ld bytes.\n",
-			    rname, (long)nread));
-
-		rc = 1;
-	}
-
-	SAFE_FREE(data);
-
 	if (!cli_close(targetcli, fnum)) {
 		d_printf("Error %s closing remote file\n",cli_errstr(cli));
 		rc = 1;