Add functions to print information about SysV mqs

Not needed yet but maybe useful..

README.md

@@ -1,5 +1,6 @@
 # mqrs
-`mqrs` is a small cli application to handle POSIX message queues.
+`mqrs` is a small cli application to handle different kinds of message
+queues.
 
 ## Install `mqrs`
 For information about how to build, install and run `mqrs` please see
@@ -8,8 +9,8 @@ For information about how to build, install and run `mqrs` please see
 ## Using `mqrs`
 Depending on which backend you want to use there are different subsets
 of subcommands. Following backends are supported:
-- `posix`: Uses POSIX message queues
-- `sysv`: Uses SysV IPC message queues
+- `posix`: Use POSIX message queues
+- `sysv`: Use SysV IPC message queues
 
 If a command is clearly distinguishable from all the others,
 it does not have to be completed further.
@@ -66,6 +67,16 @@ queue. Following optional arguments are supported:
 - `-m`, `--mode`: Permissions (octal) to create the queue
   with. Default: 0644.
 
+#### Print information about a message queue
+Use the `info` command to print further information about a message
+queue. Exactly of the following arguments is mandatory:
+- `-i`, `--id id`: Id of the queue
+- `-k`, `--key key`: Key of the queue
+
+#### List all message queues
+Use the `list` command to print a list of all message queues. No
+further arguments are supported.
+
 #### Delete a message queue
 Use the `unlink` command to delete a message queue. This can either be
 done by providing a `key` or an `id` of the queue:

mqrs.1

@@ -41,7 +41,7 @@ The POSIX backend supports six commands:
 and
 .B recv
 .
-.SS create [FLAGS] [OPTIONS] \fI<QUEUE>\fP
+.SS posix create [FLAGS] [OPTIONS] \fI<QUEUE>\fP
 Create a new POSIX message queue.
 .TP 8
 .SS ARGS
@@ -72,7 +72,7 @@ Message size in bytes
 .B \-m, \-\-mode \fI<mode>\fP
 Permissions (octal) to create the queue with
 .RE
-.SS help [SUBCOMMAND]
+.SS posix help [SUBCOMMAND]
 Prints this message or the help of the given subcommand.
 .TP 8
 .SS ARGS
@@ -81,7 +81,7 @@ Prints this message or the help of the given subcommand.
 .B \fI<SUBCOMMAND>\fP
 Show help for \fISUBCOMMAND\fP
 .RE
-.SS info [FLAGS] \fI<QUEUE>\fP
+.SS posix info [FLAGS] \fI<QUEUE>\fP
 Print further information about an existing message queue.
 .TP 8
 .SS ARGS
@@ -100,7 +100,7 @@ Prints help information
 .B \-v, \-\-verbose
 Produce verbose output
 .RE
-.SS list [FLAGS]
+.SS posix list [FLAGS]
 Print a list of all existing POSIX message queues.
 .TP 8
 .SS FLAGS
@@ -115,7 +115,7 @@ Produce verbose output
 .B \-a, \-\-all
 Print all available information
 .RE
-.SS recv [FLAGS] [OPTIONS] \fI<QUEUE>\fP
+.SS posix recv [FLAGS] [OPTIONS] \fI<QUEUE>\fP
 Receive and print one or more messages message from a message queue.
 .TP 8
 .SS ARGS
@@ -153,7 +153,7 @@ Deadline until messages are received (format: "%Y-%m-%d %H:%M:%S")
 .B \-o, \-\-timeout \fI<timeout>\fP
 Timeout as for example in "5h 23min 42ms"
 .RE
-.SS send [FLAGS] [OPTIONS] \fI<QUEUE>\fP \fI<MESSAGE>\fP
+.SS posix send [FLAGS] [OPTIONS] \fI<QUEUE>\fP \fI<MESSAGE>\fP
 Send a message to a message queue.
 .TP 8
 .SS ARGS
@@ -191,7 +191,7 @@ Set a different priority than default, priority >= 0 [default: 0]
 .B \-o, \-\-timeout \fI<timeout>\fP
 Timeout as for example in "5h 23min 42ms"
 .RE
-.SS unlink [FLAGS] \fI<QUEUE>\fP
+.SS posix unlink [FLAGS] \fI<QUEUE>\fP
 Delete an existing POSIX message queue.
 .TP 8
 .SS ARGS
@@ -211,12 +211,16 @@ Prints help information
 Produce verbose output
 .RE
 .SH SYSV IPC MESSAGE QUEUE SUBCOMMANDS
-The SysV IPC backend supports two commands:
+The SysV IPC backend supports four commands:
 .B create\
+,
+.B info\
+,
+.B list
 and
 .B unlink\
 .
-.SS create [FLAGS] [OPTIONS] \fI<KEY>\fP
+.SS sysv create [FLAGS] [OPTIONS] \fI<KEY>\fP
 Create a new SysV IPC message queue.
 .TP 8
 .SS ARGS
@@ -241,7 +245,51 @@ Produce verbose output
 .B \-m, \-\-mode \fI<mode>\fP
 Permissions (octal) to create the queue with (default: 0644)
 .RE
-.SS unlink [FLAGS] [OPTIONS]
+.SS sysv help [SUBCOMMAND]
+Prints this message or the help of the given subcommand.
+.TP 8
+.SS ARGS
+.RS
+.TP 8
+.B \fI<SUBCOMMAND>\fP
+Show help for \fISUBCOMMAND\fP
+.RE
+.SS sysv info [FLAGS] [OPTIONS]
+Print further information about an existing message queue. Exactly of
+the OPTION arguments is mandatory.
+.TP 8
+.SS FLAGS
+.RS
+.TP 8
+.B \-h, \-\-help
+Prints help information
+.TP 8
+.B \-v, \-\-verbose
+Produce verbose output
+.RE
+.TP 8
+.SS OPTIONS
+.RS
+.TP 8
+.B \-i, \-\-id \fI<id>\fP
+Id of the queue
+.TP 8
+.B \-k, \-\-key \fI<key>\fP
+Key of the queue
+.RE
+.SS sysv list [FLAGS]
+Print a list of all existing SysV IPC message queues.
+.TP 8
+.SS FLAGS
+.RS
+.TP 8
+.B \-h, \-\-help
+Prints help information
+.TP 8
+.B \-v, \-\-verbose
+Produce verbose output
+.RE
+.SS sysv unlink [FLAGS] [OPTIONS]
 Delete an existing SysV IPC message queue. It is mandatory to pass
 exactly one OPTION.
 .TP 8

src/main.rs

@@ -25,6 +25,8 @@ enum PosixCommand {
 #[derive(Clap, Debug)]
 enum SysvCommand {
     Create(sysv::Create),
+    Info(sysv::Info),
+    List(sysv::List),
     Unlink(sysv::Unlink),
 }
 
@@ -69,6 +71,8 @@ fn main() -> Result<()> {
         },
         Backend::Sysv(s) => match s {
             SysvCommand::Create(c) => c.run()?,
+            SysvCommand::Info(i) => i.run()?,
+            SysvCommand::List(l) => l.run()?,
             SysvCommand::Unlink(u) => u.run()?,
         },
     }

src/posix/info.rs

@@ -7,7 +7,7 @@ use posixmq::PosixMq;
 pub struct Info {
     /// Name of the queue
     #[clap(value_name = "QUEUE")]
-    pub queue: String,
+    queue: String,
 }
 
 impl Info {

src/posix/list.rs

@@ -4,7 +4,7 @@ use clap::Clap;
 use log::warn;
 use std::{fs, os::unix::fs::PermissionsExt};
 
-/// Print information about an existing message queue
+/// Print a list of existing message queues
 #[derive(Clap, Debug)]
 pub struct List {
     /// Show all parameters

src/posix/recv.rs

@@ -11,22 +11,22 @@ use std::str;
 pub struct Recv {
     /// Do not block
     #[clap(short, long)]
-    pub non_blocking: bool,
+    non_blocking: bool,
     /// Print messages as they are received
     #[clap(short, long)]
-    pub follow: bool,
+    follow: bool,
     /// Print a timestamp before each message
     #[clap(short, long)]
-    pub timestamp: bool,
+    timestamp: bool,
     /// Timeout, example "5h 23min 42ms"
     #[clap(short = 'o', long, conflicts_with = "deadline")]
-    pub timeout: Option<String>,
+    timeout: Option<String>,
     /// Deadline until messages are received (format: "%Y-%m-%d %H:%M:%S")
     #[clap(short, long, conflicts_with = "timeout")]
-    pub deadline: Option<String>,
+    deadline: Option<String>,
     /// Name of the queue
     #[clap(value_name = "QUEUE")]
-    pub queue: String,
+    queue: String,
 }
 
 fn print_message(priority: u32, length: usize, timestamp: bool, msg: &str) {

src/posix/send.rs

@@ -9,22 +9,22 @@ use log::info;
 pub struct Send {
     /// Set a different priority, priority >= 0
     #[clap(short, long, default_value = "0")]
-    pub priority: u32,
+    priority: u32,
     /// Do not block
     #[clap(short, long)]
-    pub non_blocking: bool,
+    non_blocking: bool,
     /// Timeout, example "5h 23min 42ms"
     #[clap(short = 'o', long, conflicts_with = "deadline")]
-    pub timeout: Option<String>,
+    timeout: Option<String>,
     /// Deadline until messages are sent (format: "%Y-%m-%d %H:%M:%S")
     #[clap(short, long, conflicts_with = "timeout")]
-    pub deadline: Option<String>,
+    deadline: Option<String>,
     /// Name of the queue
     #[clap(value_name = "QUEUE")]
-    pub queue: String,
+    queue: String,
     /// Message to be sent to the queue
     #[clap(value_name = "MESSAGE")]
-    pub msg: String,
+    msg: String,
 }
 
 impl Send {

src/sysv.rs

@@ -1,5 +1,9 @@
 mod create;
+mod info;
+mod list;
 mod unlink;
 
 pub use create::Create;
+pub use info::Info;
+pub use list::List;
 pub use unlink::Unlink;

src/sysv/info.rs

@@ -0,0 +1,53 @@
+use anyhow::Result;
+use clap::Clap;
+use std::{
+    fs::File,
+    io::{BufRead, BufReader},
+};
+
+/// Print information about an existing message queue
+#[derive(Clap, Debug)]
+pub struct Info {
+    /// Id of the queue
+    #[clap(short, long, required_unless_present_any = &["key"], conflicts_with = "key")]
+    id: Option<i32>,
+    /// Key of the queue
+    #[clap(short, long, required_unless_present_any = &["id"], conflicts_with = "id")]
+    key: Option<i32>,
+}
+
+fn print_line(line: &str) {
+    for field in line.split_whitespace().collect::<Vec<&str>>() {
+        print!("{0: <10}", field);
+    }
+
+    println!();
+}
+
+impl Info {
+    pub fn run(&self) -> Result<()> {
+        let mut lines = BufReader::new(File::open("/proc/sysvipc/msg")?).lines();
+
+        print_line(&lines.nth(0).unwrap_or(Ok(String::new()))?);
+
+        for line in lines {
+            let line = line?;
+
+            if let Some(id) = self.id {
+                if id == line.split_whitespace().collect::<Vec<&str>>()[1].parse::<i32>()? {
+                    print_line(&line);
+
+                    break;
+                }
+            } else if let Some(key) = self.key {
+                if key == line.split_whitespace().collect::<Vec<&str>>()[0].parse::<i32>()? {
+                    print_line(&line);
+
+                    break;
+                }
+            }
+        }
+
+        Ok(())
+    }
+}

src/sysv/list.rs

@@ -0,0 +1,24 @@
+use anyhow::Result;
+use clap::Clap;
+use std::{
+    fs::File,
+    io::{BufRead, BufReader},
+};
+
+/// Print a list of existing message queues
+#[derive(Clap, Debug)]
+pub struct List {}
+
+impl List {
+    pub fn run(&self) -> Result<()> {
+        for line in BufReader::new(File::open("/proc/sysvipc/msg")?).lines() {
+            for field in line?.split_whitespace().collect::<Vec<&str>>() {
+                print!("{0: <10}", field);
+            }
+
+            println!();
+        }
+
+        Ok(())
+    }
+}

src/sysv/unlink.rs

@@ -7,15 +7,15 @@ use log::info;
 pub struct Unlink {
     /// Id of the queue
     #[clap(
-        long,
         short,
+        long,
         required_unless_present_any = &["key"],
         conflicts_with = "key"
     )]
-    pub id: Option<i32>,
+    id: Option<i32>,
     /// Key of the queue
-    #[clap(long, short, required_unless_present_any = &["id"], conflicts_with = "id")]
-    pub key: Option<i32>,
+    #[clap(short, long, required_unless_present_any = &["id"], conflicts_with = "id")]
+    key: Option<i32>,
 }
 
 impl Unlink {
@@ -25,9 +25,11 @@ impl Unlink {
 
             info!("Removed message queue with id: {}", id);
         } else if let Some(key) = self.key {
-            sysvmq::unlink_key(key)?;
+            let id = sysvmq::id_from_key(key)?;
 
-            info!("Removed message queue key: {}", key);
+            sysvmq::unlink_id(id)?;
+
+            info!("Removed message queue key: {} (id: {})", key, id);
         }
 
         Ok(())

sysvmq/src/lib.rs

@@ -1,21 +1,15 @@
 use libc::{
-    msgctl, msgget, msqid_ds, IPC_CREAT, IPC_EXCL, IPC_INFO, IPC_NOWAIT, IPC_PRIVATE, IPC_RMID,
-    IPC_SET, IPC_STAT, MSG_COPY, MSG_EXCEPT, MSG_INFO, MSG_NOERROR, MSG_STAT,
+    msgctl, msgget, msginfo, msqid_ds, IPC_CREAT, IPC_EXCL, IPC_INFO, IPC_NOWAIT, IPC_PRIVATE,
+    IPC_RMID, IPC_SET, IPC_STAT, MSG_COPY, MSG_EXCEPT, MSG_INFO, MSG_NOERROR, MSG_STAT,
 };
 use nix::errno::{errno, Errno};
-use std::{marker::PhantomData, num::ParseIntError, ptr};
+use std::{marker::PhantomData, mem::MaybeUninit, ptr};
 use thiserror::Error;
 
 #[derive(Debug, Error)]
 pub enum SysvMqError {
     #[error("SysV message queue: {0}")]
     ErrnoError(&'static str),
-    #[error("No message queue found with key {0}")]
-    KeyNotFound(i32),
-    #[error("IO Error: {0}")]
-    IoError(#[from] std::io::Error),
-    #[error("Parse Error: {0}")]
-    ParserError(#[from] ParseIntError),
 }
 
 /// IPC bit flags
@@ -69,10 +63,63 @@ pub fn unlink_id(id: i32) -> Result<(), SysvMqError> {
     }
 }
 
-pub fn unlink_key(key: i32) -> Result<(), SysvMqError> {
+pub fn id_from_key(key: i32) -> Result<i32, SysvMqError> {
     let id = unsafe { msgget(key, 0) };
 
-    unlink_id(id)
+    match id {
+        -1 => Err(SysvMqError::ErrnoError(Errno::from_i32(errno()).desc())),
+        id => Ok(id),
+    }
+}
+
+pub fn ipc_info(id: i32) -> Result<(), SysvMqError> {
+    let mut msginfo = MaybeUninit::<msginfo>::uninit();
+
+    unsafe {
+        msgctl(
+            id,
+            ControlCommands::IpcInfo as i32,
+            msginfo.as_mut_ptr() as *mut msqid_ds,
+        );
+    }
+
+    let msginfo = unsafe { msginfo.assume_init() };
+
+    println!("info: {:?}", msginfo);
+
+    Ok(())
+}
+
+pub fn stat_info(id: i32) -> Result<(), SysvMqError> {
+    let mut msginfo = MaybeUninit::<msqid_ds>::uninit();
+
+    unsafe {
+        msgctl(id, ControlCommands::Stat as i32, msginfo.as_mut_ptr());
+    }
+
+    let msginfo = unsafe { msginfo.assume_init() };
+
+    println!("info: {:?}", msginfo);
+
+    Ok(())
+}
+
+pub fn msg_info(id: i32) -> Result<(), SysvMqError> {
+    let mut msginfo = MaybeUninit::<msginfo>::uninit();
+
+    unsafe {
+        msgctl(
+            id,
+            ControlCommands::MsgInfo as i32,
+            msginfo.as_mut_ptr() as *mut msqid_ds,
+        );
+    }
+
+    let msginfo = unsafe { msginfo.assume_init() };
+
+    println!("info: {:?}", msginfo);
+
+    Ok(())
 }
 
 pub struct SysvMq<T> {