New API: ls0 - List files, separated by \0 characters.

This API is not especially useful on its own.  It will be used to
reimplement guestfs_ls to work without protocol limits.

3 files changed, 79 insertions, 1 deletions

diff --git a/daemon/ls.c b/daemon/ls.c
index 5c76d7e2..0f60a4ea 100644
--- a/daemon/ls.c
+++ b/daemon/ls.c
@@ -25,10 +25,74 @@
 #include <fcntl.h>
 #include <dirent.h>
 #include <sys/stat.h>
+#include <errno.h>
 
 #include "daemon.h"
 #include "actions.h"
 
+/* Has one FileOut parameter. */
+int
+do_ls0 (const char *path)
+{
+  DIR *dir;
+  struct dirent *d;
+  size_t len;
+
+  CHROOT_IN;
+  dir = opendir (path);
+  CHROOT_OUT;
+
+  if (dir == NULL) {
+    reply_with_perror ("opendir: %s", path);
+    return -1;
+  }
+
+  /* Now we must send the reply message, before the filenames.  After
+   * this there is no opportunity in the protocol to send any error
+   * message back.  Instead we can only cancel the transfer.
+   */
+  reply (NULL, NULL);
+
+  while (1) {
+    errno = 0;
+    d = readdir (dir);
+    if (d == NULL) break;
+
+    /* Ignore . and .. */
+    if (STREQ (d->d_name, ".") || STREQ (d->d_name, ".."))
+      continue;
+
+    /* Send the name in a single chunk.  XXX Needs to be fixed if
+     * names can be longer than the chunk size.  Note we use 'len+1'
+     * because we want to include the \0 terminating character in the
+     * output.
+     */
+    len = strlen (d->d_name);
+    if (send_file_write (d->d_name, len+1) < 0) {
+      closedir (dir);
+      return -1;
+    }
+  }
+
+  if (errno != 0) {
+    perror (path);
+    send_file_end (1);          /* Cancel. */
+    closedir (dir);
+    return -1;
+  }
+
+  if (closedir (dir) == -1) {
+    perror (path);
+    send_file_end (1);          /* Cancel. */
+    return -1;
+  }
+
+  if (send_file_end (0))	/* Normal end of file. */
+    return -1;
+
+  return 0;
+}
+
 char **
 do_ls (const char *path)
 {
diff --git a/generator/generator_actions.ml b/generator/generator_actions.ml
index 9c45a663..be2db82a 100644
--- a/generator/generator_actions.ml
+++ b/generator/generator_actions.ml
@@ -9425,6 +9425,20 @@ so the target must be set up not to require one.
 
 The optional arguments are the same as those of C<guestfs_rsync>." };
 
+  { defaults with
+    name = "ls0";
+    style = RErr, [Pathname "dir"; FileOut "filenames"], [];
+    proc_nr = Some 347;
+    shortdesc = "get list of files in a directory";
+    longdesc = "\
+This specialized command is used to get a listing of
+the filenames in the directory C<dir>.  The list of filenames
+is written to the local file C<filenames> (on the host).
+
+In the output file, the filenames are separated by C<\\0> characters.
+
+C<.> and C<..> are not returned.  The filenames are not sorted." };
+
 ]
 
 (* Non-API meta-commands available only in guestfish.
diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR
index 99ca0d5f..538ad4bc 100644
--- a/src/MAX_PROC_NR
+++ b/src/MAX_PROC_NR
@@ -1 +1 @@
-346
+347