Libguestfs - Jul 2023 - [libguestfs PATCH] lib: remove guestfs_int_cmd_clear_close_files()

The last (only?) caller of guestfs_int_cmd_clear_close_files() disappeared
in commit e4c396888056 ("lib/info: Remove /dev/fd hacking and pass a true
filename to qemu-img info.", 2018-01-23), part of v1.37.36.

Simplify the code by removing guestfs_int_cmd_clear_close_files().

Signed-off-by: Laszlo Ersek <lersek at redhat.com>
---
 lib/guestfs-internal.h |  1 -
 lib/command.c          | 37 ++++++++++---------------------------
 2 files changed, 10 insertions(+), 28 deletions(-)

diff --git a/lib/guestfs-internal.h b/lib/guestfs-internal.h
index fb55e02614f5..c7ef32277e93 100644
--- a/lib/guestfs-internal.h
+++ b/lib/guestfs-internal.h
@@ -751,7 +751,6 @@ extern void guestfs_int_cmd_set_stdout_callback (struct
command *, cmd_stdout_ca
 extern void guestfs_int_cmd_set_stderr_to_stdout (struct command *);
 extern void guestfs_int_cmd_set_child_rlimit (struct command *, int resource,
long limit);
 extern void guestfs_int_cmd_clear_capture_errors (struct command *);
-extern void guestfs_int_cmd_clear_close_files (struct command *);
 extern void guestfs_int_cmd_set_child_callback (struct command *,
cmd_child_callback child_callback, void *data);
 extern int guestfs_int_cmd_run (struct command *);
 extern void guestfs_int_cmd_close (struct command *);
diff --git a/lib/command.c b/lib/command.c
index 515ef624bd96..82a47bafa9e5 100644
--- a/lib/command.c
+++ b/lib/command.c
@@ -152,9 +152,6 @@ struct command
   /* When using the pipe_* APIs, stderr is pointed to a temporary file. */
   char *error_file;
 
-  /* Close file descriptors (defaults to true). */
-  bool close_files;
-
   /* Supply a callback to receive stdout. */
   cmd_stdout_callback stdout_callback;
   void *stdout_data;
@@ -186,7 +183,6 @@ guestfs_int_new_command (guestfs_h *g)
   cmd = safe_calloc (g, 1, sizeof *cmd);
   cmd->g = g;
   cmd->capture_errors = true;
-  cmd->close_files = true;
   cmd->errorfd = -1;
   cmd->outfd = -1;
   return cmd;
@@ -358,17 +354,6 @@ guestfs_int_cmd_clear_capture_errors (struct command *cmd)
   cmd->capture_errors = false;
 }
 
-/**
- * Don't close file descriptors after the fork.
- *
- * XXX Should allow single fds to be sent to child process.
- */
-void
-guestfs_int_cmd_clear_close_files (struct command *cmd)
-{
-  cmd->close_files = false;
-}
-
 /**
  * Set a function to be executed in the child, right before the
  * execution.  Can be used to setup the child, for example changing
@@ -564,18 +549,16 @@ run_child (struct command *cmd, char **env)
   for (i = 1; i < NSIG; ++i)
     sigaction (i, &sa, NULL);
 
-  if (cmd->close_files) {
-    /* Close all other file descriptors.  This ensures that we don't
-     * hold open (eg) pipes from the parent process.
-     */
-    max_fd = sysconf (_SC_OPEN_MAX);
-    if (max_fd == -1)
-      max_fd = 1024;
-    if (max_fd > 65536)
-      max_fd = 65536;        /* bound the amount of work we do here */
-    for (fd = 3; fd < max_fd; ++fd)
-      close (fd);
-  }
+  /* Close all other file descriptors.  This ensures that we don't
+   * hold open (eg) pipes from the parent process.
+   */
+  max_fd = sysconf (_SC_OPEN_MAX);
+  if (max_fd == -1)
+    max_fd = 1024;
+  if (max_fd > 65536)
+    max_fd = 65536;        /* bound the amount of work we do here */
+  for (fd = 3; fd < max_fd; ++fd)
+    close (fd);
 
   /* Set the umask for all subcommands to something sensible (RHBZ#610880). */
   umask (022);

On Tue, Jul 11, 2023 at 01:39:06PM +0200, Laszlo Ersek
wrote:
> The last (only?) caller of guestfs_int_cmd_clear_close_files() disappeared
> in commit e4c396888056 ("lib/info: Remove /dev/fd hacking and pass a
true
> filename to qemu-img info.", 2018-01-23), part of v1.37.36.
> 
> Simplify the code by removing guestfs_int_cmd_clear_close_files().
> 
> Signed-off-by: Laszlo Ersek <lersek at redhat.com>
> ---
>  lib/guestfs-internal.h |  1 -
>  lib/command.c          | 37 ++++++++++---------------------------
>  2 files changed, 10 insertions(+), 28 deletions(-)
> 
> diff --git a/lib/guestfs-internal.h b/lib/guestfs-internal.h
> index fb55e02614f5..c7ef32277e93 100644
> --- a/lib/guestfs-internal.h
> +++ b/lib/guestfs-internal.h
> @@ -751,7 +751,6 @@ extern void guestfs_int_cmd_set_stdout_callback (struct
command *, cmd_stdout_ca
>  extern void guestfs_int_cmd_set_stderr_to_stdout (struct command *);
>  extern void guestfs_int_cmd_set_child_rlimit (struct command *, int
resource, long limit);
>  extern void guestfs_int_cmd_clear_capture_errors (struct command *);
> -extern void guestfs_int_cmd_clear_close_files (struct command *);
>  extern void guestfs_int_cmd_set_child_callback (struct command *,
cmd_child_callback child_callback, void *data);
>  extern int guestfs_int_cmd_run (struct command *);
>  extern void guestfs_int_cmd_close (struct command *);
> diff --git a/lib/command.c b/lib/command.c
> index 515ef624bd96..82a47bafa9e5 100644
> --- a/lib/command.c
> +++ b/lib/command.c
> @@ -152,9 +152,6 @@ struct command
>    /* When using the pipe_* APIs, stderr is pointed to a temporary file. */
>    char *error_file;
>  
> -  /* Close file descriptors (defaults to true). */
> -  bool close_files;
> -
>    /* Supply a callback to receive stdout. */
>    cmd_stdout_callback stdout_callback;
>    void *stdout_data;
> @@ -186,7 +183,6 @@ guestfs_int_new_command (guestfs_h *g)
>    cmd = safe_calloc (g, 1, sizeof *cmd);
>    cmd->g = g;
>    cmd->capture_errors = true;
> -  cmd->close_files = true;
>    cmd->errorfd = -1;
>    cmd->outfd = -1;
>    return cmd;
> @@ -358,17 +354,6 @@ guestfs_int_cmd_clear_capture_errors (struct command
*cmd)
>    cmd->capture_errors = false;
>  }
>  
> -/**
> - * Don't close file descriptors after the fork.
> - *
> - * XXX Should allow single fds to be sent to child process.
> - */
> -void
> -guestfs_int_cmd_clear_close_files (struct command *cmd)
> -{
> -  cmd->close_files = false;
> -}
> -
>  /**
>   * Set a function to be executed in the child, right before the
>   * execution.  Can be used to setup the child, for example changing
> @@ -564,18 +549,16 @@ run_child (struct command *cmd, char **env)
>    for (i = 1; i < NSIG; ++i)
>      sigaction (i, &sa, NULL);
>  
> -  if (cmd->close_files) {
> -    /* Close all other file descriptors.  This ensures that we don't
> -     * hold open (eg) pipes from the parent process.
> -     */
> -    max_fd = sysconf (_SC_OPEN_MAX);
> -    if (max_fd == -1)
> -      max_fd = 1024;
> -    if (max_fd > 65536)
> -      max_fd = 65536;        /* bound the amount of work we do here */
> -    for (fd = 3; fd < max_fd; ++fd)
> -      close (fd);
> -  }
> +  /* Close all other file descriptors.  This ensures that we don't
> +   * hold open (eg) pipes from the parent process.
> +   */
> +  max_fd = sysconf (_SC_OPEN_MAX);
> +  if (max_fd == -1)
> +    max_fd = 1024;
> +  if (max_fd > 65536)
> +    max_fd = 65536;        /* bound the amount of work we do here */
> +  for (fd = 3; fd < max_fd; ++fd)
> +    close (fd);
>  
>    /* Set the umask for all subcommands to something sensible
(RHBZ#610880). */
>    umask (022);
Reviewed-by: Richard W.M. Jones <rjones at redhat.com>


-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
libguestfs lets you edit virtual machines.  Supports shell scripting,
bindings from many languages.  http://libguestfs.org