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//!Rust bindings for writing Slurm SPANK Plugins
//!# Introduction
//!This crate allows to write Slurm SPANK plugins using Rust. To learn more
//!about capabilities available through SPANK please refer to the official
//![`SPANK documentation`].
//!
//! [`SPANK documentation`]: https://slurm.schedmd.com/spank.html
//!
//!To create a SPANK plugin using this crate, you need to define a struct for
//!which you implement the [`Plugin`] trait and to make it available as a SPANK
//!plugin using the [`SPANK_PLUGIN!`] macro.
//!
//!The methods of the Plugin trait correspond to the callbacks defined by the
//!SPANK API such as [`init_post_opt`], [`task_post_fork`] etc. These methods
//!have a default implementation which means you only need to implement the
//!callbacks relevant for your plugin.
//!
//! [`init_post_opt`]: crate::Plugin::init_post_opt
//!
//! [`task_post_fork`]: crate::Plugin::task_post_fork
//!
//!Each callback method is passed a [`SpankHandle`] reference which allows to
//!interact with Slurm through the SPANK API.
//!
//!When returning an [`Err`] from a callback an error message will be displayed
//!and/or logged by default, depending on the context. This behaviour may be
//!overridden by the [`report_error`] method. A default [`Subscriber`] is also
//!configured to facilitate the use of the [`tracing`] crate for logging and
//!error reporting while using SPANK log facilities, such as in the example
//!below. This can be overridden by the [`setup`] method.
//!
//! [`report_error`]: crate::Plugin::report_error
//!
//! [`Subscriber`]: tracing::Subscriber
//!
//! [`setup`]: crate::Plugin::setup
//!
//!# Example: hello.so
//!The following example implements a simple hello world plugin. A more complete
//!example is provided in the example directory of the repository which shows
//!how to implement the same renice plugin that is given as an example of the C
//!SPANK API in the Slurm [`SPANK documentation`].
//!```rust,no_run
#![doc = include_str!("hello.md")]
//! ```
//! The following Cargo.toml can be used to build this example plugin
//!```toml
//! [package]
//! name = "slurm-spank-hello"
//! version = "0.1.0"
//! edition = "2021"
//!
//! [lib]
//! crate-type = ["cdylib"]
//!
//! [dependencies]
//! eyre = "0.6.8"
//! slurm-spank = "0.3"
//! tracing = "0.1.37"
//!```
use lazy_static::lazy_static;
use libc::{gid_t, pid_t, uid_t};
use num_enum::{FromPrimitive, IntoPrimitive, TryFromPrimitive};
use std::borrow::Cow;
use std::collections::HashMap;
use std::convert::{TryFrom, TryInto};
use std::error::Error;
use std::ffi::{CStr, CString, OsStr, OsString};
use std::fmt;
use std::os::raw::{c_char, c_int};
use std::os::unix::ffi::OsStrExt;
use std::panic::catch_unwind;
use std::panic::UnwindSafe;
use std::sync::Mutex;
use std::{ptr, slice};
use tracing::{error, span};
use tracing_core::{Event, Subscriber};
use tracing_subscriber::fmt::{
format::Writer, layer, FmtContext, FormatEvent, FormatFields, FormattedFields,
};
use tracing_subscriber::prelude::*;
use tracing_subscriber::registry::LookupSpan;
use tracing_subscriber::{EnvFilter, Registry};
#[doc(hidden)]
pub mod spank_sys;
#[doc(hidden)]
pub use byte_strings;
/// Handle to the Slurm interface exposed to SPANK plugins. It provides methods
/// to query Slurm from a plugin.
pub struct SpankHandle<'a> {
spank: spank_sys::spank_t,
argc: c_int,
argv: *const *const c_char,
opt_cache: &'a mut OptionCache,
}
macro_rules! spank_item_getter {
($(#[$outer:meta])* $name:ident, $spank_item:path, $arg_name:ident, $arg_type:ty, $result_type:ty) => {
$(#[$outer])*
pub fn $name(&self, $arg_name: $arg_type) -> Result<$result_type, SpankError> {
let mut res: $result_type = <$result_type>::default();
let res_ptr: *mut $result_type = &mut res;
match unsafe {
spank_sys::spank_get_item(self.spank, $spank_item.into(), $arg_name, res_ptr)
} {
spank_sys::ESPANK_SUCCESS => Ok(res),
spank_sys::slurm_err_t_ESPANK_NOEXIST => Err(SpankError::from_noexist($arg_name)),
e => Err(SpankError::from_spank_item("spank_get_item", $spank_item, e)),
}
}
};
($(#[$outer:meta])* $name:ident, $spank_item:path, &str) => {
$(#[$outer])*
pub fn $name(&self) -> Result<&str, SpankError> {
let mut res: *const c_char = ptr::null_mut();
let res_ptr: *mut *const c_char = &mut res;
match unsafe { spank_sys::spank_get_item(self.spank, $spank_item.into(), res_ptr) } {
spank_sys::ESPANK_SUCCESS => {
if res.is_null() {
panic!("Received unexpected null pointer from spank_get_item")
} else {
let cstr = unsafe { CStr::from_ptr(res) };
cstr.to_str()
.map_err(|_| SpankError::Utf8Error(cstr.to_string_lossy().to_string()))
}
}
e => Err(SpankError::from_spank_item("spank_get_item", $spank_item, e)),
}
}
};
($(#[$outer:meta])* $name:ident, $spank_item:path,$result_type:ty) => {
$(#[$outer])*
pub fn $name(&self) -> Result<$result_type, SpankError> {
let mut res: $result_type = <$result_type>::default();
let res_ptr: *mut $result_type = &mut res;
match unsafe { spank_sys::spank_get_item(self.spank, $spank_item.into(), res_ptr) } {
spank_sys::ESPANK_SUCCESS => Ok(res),
e => Err(SpankError::from_spank_item("spank_get_item", $spank_item, e)),
}
}
};
}
fn os_value_to_lossy(value: Cow<'_, OsStr>) -> Cow<'_, str> {
match value {
Cow::Borrowed(value) => value.to_string_lossy(),
Cow::Owned(value) => match value.into_string() {
Ok(utf8_value) => Cow::from(utf8_value),
Err(value) => Cow::from(value.to_string_lossy().into_owned()),
},
}
}
fn os_value_to_str(value: Cow<'_, OsStr>) -> Result<Cow<'_, str>, SpankError> {
match value {
Cow::Borrowed(value) => Ok(Cow::from(
value
.to_str()
.ok_or_else(|| SpankError::from_os_str(value))?,
)),
Cow::Owned(value) => {
Ok(Cow::from(value.into_string().map_err(|value_err| {
SpankError::from_os_str(&value_err)
})?))
}
}
}
// XXX: Unfortunately, according to the documentation, there are some contexts
// where you can only use callbacks (init_post_opt) and others where you can
// only use getopt (prolog/epilog). This is an attempt at providing a uniform
// interface by caching callbacks or calls to getopt which feels quite hackish.
// We should try to find a cleaner interface.
#[derive(Default, Debug)]
#[doc(hidden)]
pub struct OptionCache {
pub options: Vec<String>,
pub values: HashMap<String, Option<OsString>>,
}
impl<'a> SpankHandle<'a> {
/// Returns the context in which the calling plugin is loaded.
pub fn context(&self) -> Result<Context, SpankError> {
let ctx = unsafe { spank_sys::spank_context() };
Context::try_from(ctx).map_err(|_| {
SpankError::from_spank("spank_context", spank_sys::slurm_err_t_ESPANK_ERROR)
})
}
/// Registers a plugin-provided option dynamically. This function is only
/// valid when called from a plugin's `init()`, and must be guaranteed to be
/// called in all contexts in which it is used (local, remote, allocator).
pub fn register_option(&mut self, spank_opt: SpankOption) -> Result<(), SpankError> {
let arginfo = match &spank_opt.arginfo {
None => None,
Some(info) => Some(CString::new(info as &str).map_err(|_| SpankError::from_str(info))?),
};
let name = CString::new(&spank_opt.name as &str)
.map_err(|_| SpankError::from_str(&spank_opt.name))?;
let usage = match spank_opt.usage {
None => None,
Some(usage) => {
Some(CString::new(&usage as &str).map_err(|_| SpankError::from_str(&usage))?)
}
};
let mut c_spank_opt = spank_sys::spank_option {
name: name.as_ptr(),
has_arg: arginfo.is_some() as i32,
cb: Some(spank_option_callback),
arginfo: match arginfo {
Some(ref arginfo) => arginfo.as_ptr(),
None => ptr::null(),
},
usage: match usage {
Some(ref usage) => usage.as_ptr(),
None => ptr::null(),
},
val: self
.opt_cache
.options
.len()
.try_into()
.expect("Argument table overflow"),
};
match unsafe { spank_sys::spank_option_register(self.spank, &mut c_spank_opt) } {
spank_sys::ESPANK_SUCCESS => {
self.opt_cache.options.push(spank_opt.name);
Ok(())
}
e => Err(SpankError::from_spank("spank_option_register", e)),
}
}
/// Returns the list of arguments configured in the `plugstack.conf` file
/// for this plugin
pub fn plugin_argv(&self) -> Result<Vec<&str>, SpankError> {
self.argv_to_vec(self.argc as usize, self.argv)
}
/// Prepends the vector of str `argv` to the argument vector of the task
/// to be spawned. This function can be invoked from the following
/// functions: slurm_spank_task_init_privileged, and slurm_spank_task_init.
///
/// An error is returned if called outside of a task context or if the
/// argument vector is invalid.
pub fn prepend_task_argv(&self, argv: Vec<&str>) -> Result<(), SpankError> {
let c_argv: Vec<CString> = argv
.iter()
.map(|&arg| CString::new(arg).map_err(|_| SpankError::from_str(arg)))
.collect::<Result<Vec<CString>, SpankError>>()?;
self.prepend_task_cstring(c_argv)
}
/// Prepends the vector of OsStr `argv` to the argument vector of the task
/// to be spawned. This function can be invoked from the following
/// functions: slurm_spank_task_init_privileged, and slurm_spank_task_init.
///
/// An error is returned if called outside of a task context or if the
/// argument vector is invalid.
pub fn prepend_task_argv_os(&self, argv: Vec<&OsStr>) -> Result<(), SpankError> {
let c_argv: Vec<CString> = argv
.iter()
.map(|&arg| {
CString::new(arg.as_bytes())
.map_err(|_| SpankError::CStringError(arg.to_string_lossy().to_string()))
})
.collect::<Result<Vec<CString>, SpankError>>()?;
self.prepend_task_cstring(c_argv)
}
fn prepend_task_cstring(&self, argv: Vec<CString>) -> Result<(), SpankError> {
let mut c_argv_ptrs: Vec<*const c_char> = argv.iter().map(|arg| arg.as_ptr()).collect();
let c_argv_ptr: *mut *const c_char = c_argv_ptrs.as_mut_ptr();
let count = i32::try_from(argv.len()).map_err(|_| SpankError::Overflow(argv.len()))?;
match unsafe { spank_sys::spank_prepend_task_argv(self.spank, count, c_argv_ptr) } {
spank_sys::ESPANK_SUCCESS => Ok(()),
e => Err(SpankError::from_spank("spank_prepend_task_argv", e)),
}
}
fn argv_to_vec(
&self,
argc: usize,
argv: *const *const c_char,
) -> Result<Vec<&str>, SpankError> {
unsafe { slice::from_raw_parts(argv, argc) }
.iter()
.map(|&arg| {
let cstr = unsafe { CStr::from_ptr(arg) };
cstr.to_str().map_err(|_| SpankError::from_cstr(cstr))
})
.collect::<Result<Vec<_>, _>>()
}
fn argv_to_vec_os(&self, argc: usize, argv: *const *const c_char) -> Vec<&OsStr> {
unsafe { slice::from_raw_parts(argv, argc) }
.iter()
.map(|&arg| OsStr::from_bytes(unsafe { CStr::from_ptr(arg) }.to_bytes()))
.collect()
}
/// Retrieves the environment variable `name` from the job's environment as
/// a String
///
/// This function returns Ok(none) if the environment variable is not set.
/// It returns an error if the value is not a valid UTF-8 string or if
/// called outside of remote context. To access job environment variables
/// from local context, use std::env directly
pub fn getenv<N: AsRef<OsStr>>(&self, name: N) -> Result<Option<String>, SpankError> {
match self.do_getenv_os(name, spank_sys::spank_getenv)? {
None => Ok(None),
Some(env) => Ok(Some(
env.into_string().map_err(|e| SpankError::from_os_str(&e))?,
)),
}
}
/// Retrieves the environment variable `name` from the job's environment as
/// a lossy String
///
/// If the value contains invalid UTF-8 code points, those invalid points
/// will be replaced with � (U+FFFD). This function returns Ok(none) if the
/// environment variable is not set. It returns an error if called outside
/// of remote context. To access job environment variables from local
/// context, use std::env directly
pub fn getenv_lossy<N: AsRef<OsStr>>(&self, name: N) -> Result<Option<String>, SpankError> {
self.do_getenv_os(name, spank_sys::spank_getenv)
.map(|env| env.map(|s| s.to_string_lossy().into_owned()))
}
/// Retrieves the environment variable `name` from the job's environment as
/// an OsString
///
/// The return value is an OsString which can hold arbitrary sequences of
/// bytes on Unix-like systems. This function returns Ok(none) if the
/// environment variable is not set. It returns an error if called outside
/// of remote context. To access job environment variables from local
/// context, use std::env directly
pub fn getenv_os<N: AsRef<OsStr>>(&self, name: N) -> Result<Option<OsString>, SpankError> {
self.do_getenv_os(name, spank_sys::spank_getenv)
}
/// Retrieves the environment variable `name` from the job's control
/// environment as a String
///
/// This function returns Ok(none) if the environment variable is not set.
/// It returns an error if the value is not a valid UTF-8 string or if
/// called outside of local/allocator context. To access job control environment
/// variables from job script context, use std::env directly.
pub fn job_control_getenv<N: AsRef<OsStr>>(
&self,
name: N,
) -> Result<Option<String>, SpankError> {
match self.do_getenv_os(name, spank_sys::spank_job_control_getenv)? {
None => Ok(None),
Some(env) => Ok(Some(
env.into_string().map_err(|e| SpankError::from_os_str(&e))?,
)),
}
}
/// Retrieves the environment variable `name` from the job's control
/// environment as a lossy String
///
/// If the value contains invalid UTF-8 code points, those invalid points
/// will be replaced with � (U+FFFD). This function returns Ok(none) if the
/// environment variable is not set. It returns an error if called outside
/// of local/allocator context. To access job control environment variables from
/// job script context, use std::env directly.
pub fn job_control_getenv_lossy<N: AsRef<OsStr>>(
&self,
name: N,
) -> Result<Option<String>, SpankError> {
self.do_getenv_os(name, spank_sys::spank_job_control_getenv)
.map(|env| env.map(|s| s.to_string_lossy().into_owned()))
}
/// Retrieves the environment variable `name` from the job's control
/// environment as an OsString
///
/// The return value is an OsString which can hold arbitrary sequences of
/// bytes on Unix-like systems. This function returns Ok(none) if the
/// environment variable is not set. It returns an error if called outside
/// of local/allocator context. To access job control environment variables from
/// job script context, use std::env directly.
pub fn job_control_getenv_os<N: AsRef<OsStr>>(
&self,
name: N,
) -> Result<Option<OsString>, SpankError> {
self.do_getenv_os(name, spank_sys::spank_job_control_getenv)
}
fn do_getenv_os<N: AsRef<OsStr>>(
&self,
name: N,
spank_fn: unsafe extern "C" fn(
spank_sys::spank_t,
*const c_char,
*mut c_char,
c_int,
) -> spank_sys::spank_err_t,
) -> Result<Option<OsString>, SpankError> {
let mut max_size = 4096;
let c_name = CString::new(name.as_ref().as_bytes())
.map_err(|_| SpankError::from_str(&name.as_ref().to_string_lossy()))?;
loop {
let mut buffer = vec![0; max_size];
let buffer_ptr = buffer.as_mut_ptr();
match unsafe {
spank_fn(
self.spank,
c_name.as_ptr(),
buffer_ptr as *mut c_char,
max_size as i32,
)
} {
spank_sys::slurm_err_t_ESPANK_ENV_NOEXIST => return Ok(None),
spank_sys::ESPANK_SUCCESS => {
let cstr = unsafe { CStr::from_ptr(buffer_ptr) };
return Ok(Some(OsStr::from_bytes(cstr.to_bytes()).to_os_string()));
}
spank_sys::slurm_err_t_ESPANK_NOSPACE => {
max_size *= 2;
continue;
}
e => return Err(SpankError::from_spank("spank_getenv", e)),
}
}
}
/// Sets the environment variable `name` in the job's environment to the
/// provided `value`.
///
/// Existing values will be overwritten if `overwrite` is set. This function
/// will return an error if called outside of remote context. To access job
/// environment variables from local context, use std::env directly.
pub fn setenv<N: AsRef<OsStr>, V: AsRef<OsStr>>(
&self,
name: N,
value: V,
overwrite: bool,
) -> Result<(), SpankError> {
self.do_setenv(name, value, overwrite, spank_sys::spank_setenv)
}
/// Sets the environment variable `name` in the job's control environment to
/// the provided `value`.
///
/// Existing values will be overwritten if `overwrite` is set. This function
/// will return an error if called outside of local context. To access job
/// control environment variables from remote context, use std::env directly.
pub fn job_control_setenv<N: AsRef<OsStr>, V: AsRef<OsStr>>(
&self,
name: N,
value: V,
overwrite: bool,
) -> Result<(), SpankError> {
self.do_setenv(name, value, overwrite, spank_sys::spank_job_control_setenv)
}
pub fn do_setenv<N: AsRef<OsStr>, V: AsRef<OsStr>>(
&self,
name: N,
value: V,
overwrite: bool,
spank_fn: unsafe extern "C" fn(
spank_sys::spank_t,
*const c_char,
*const c_char,
c_int,
) -> spank_sys::spank_err_t,
) -> Result<(), SpankError> {
let c_name = CString::new(name.as_ref().as_bytes())
.map_err(|_| SpankError::from_os_str(name.as_ref()))?;
let c_value = CString::new(value.as_ref().as_bytes())
.map_err(|_| SpankError::from_os_str(value.as_ref()))?;
match unsafe {
spank_fn(
self.spank,
c_name.as_ptr(),
c_value.as_ptr(),
overwrite as c_int,
)
} {
spank_sys::ESPANK_SUCCESS => Ok(()),
spank_sys::slurm_err_t_ESPANK_ENV_EXISTS => Err(SpankError::EnvExists(
name.as_ref().to_string_lossy().to_string(),
)),
e => Err(SpankError::from_spank("spank_setenv", e)),
}
}
/// Unsets the environment variable `name` in the job's environment.
///
/// This function is a no-op if the variable is already unset. It will return an
/// error if called outside of remote context. To access the job variables
/// from local context, use std::env directly.
pub fn unsetenv<N: AsRef<OsStr>>(&self, name: N) -> Result<(), SpankError> {
self.do_unsetenv(name, spank_sys::spank_unsetenv)
}
/// Unsets the environment variable `name` in the job's control environment.
///
/// This function is a no-op if the variable is already unset. It will
/// return an error if called outside of local/allocator context. To access job
/// control environment variables from remote context, use std::env
/// directly.
pub fn job_control_unsetenv<N: AsRef<OsStr>>(&self, name: N) -> Result<(), SpankError> {
self.do_unsetenv(name, spank_sys::spank_job_control_unsetenv)
}
fn do_unsetenv<N: AsRef<OsStr>>(
&self,
name: N,
spank_fn: unsafe extern "C" fn(spank_sys::spank_t, *const c_char) -> spank_sys::spank_err_t,
) -> Result<(), SpankError> {
let c_name = CString::new(name.as_ref().as_bytes())
.map_err(|_| SpankError::from_os_str(name.as_ref()))?;
match unsafe { spank_fn(self.spank, c_name.as_ptr()) } {
spank_sys::ESPANK_SUCCESS => Ok(()),
e => Err(SpankError::from_spank("spank_unsetenv", e)),
}
}
fn getopt_os(&self, name: &str) -> Result<Option<OsString>, SpankError> {
let name_c = if let Ok(n) = CString::new(name) {
n
} else {
return Err(SpankError::from_str(name));
};
let mut c_spank_opt = spank_sys::spank_option {
name: name_c.as_ptr(),
has_arg: 1,
cb: None,
usage: ptr::null(),
arginfo: ptr::null(),
val: 0,
};
let mut optarg: *mut c_char = ptr::null_mut();
match unsafe { spank_sys::spank_option_getopt(self.spank, &mut c_spank_opt, &mut optarg) } {
spank_sys::ESPANK_SUCCESS => {
if !optarg.is_null() {
Ok(Some(
OsStr::from_bytes(unsafe { CStr::from_ptr(optarg) }.to_bytes())
.to_os_string(),
))
} else {
Ok(None)
}
}
e => Err(SpankError::from_spank("spank_option_getopt", e)),
}
}
/// Returns the value set for the option `name` as a lossy String
///
/// If the value contains invalid UTF-8 code points, those invalid points
/// will be replaced with � (U+FFFD). If the option was specified multiple
/// times, this function returns the last value provided.
///
/// *WARNING*: If options have not yet been processed (e.g in init callbacks
/// or all slurmd contexts), this function will always return None.
///
/// *WARNING*: This function always returns None for options which don't
/// take values (flag options created without takes_value()) no matter whether
/// they were used or not. To check whether a flag was set, use
/// is_option_set.
pub fn get_option_value_lossy(&self, name: &str) -> Option<Cow<'_, str>> {
self.get_option_value_os(name).map(os_value_to_lossy)
}
/// Returns the value set for the option `name` as a String
///
/// An error is returned if the value cannot be converted to a String. If
/// the option was specified multiple times, it returns the last value
/// provided.
///
/// *WARNING*: If options have not yet been processed (e.g in init callbacks
/// or all slurmd contexts), this function will always return None.
///
/// *WARNING*: This function always returns None for options which don't
/// take values (flag options created without takes_value()) no matter whether
/// they were used or not. To check whether a flag was set, use
/// is_option_set.
pub fn get_option_value(&self, name: &str) -> Result<Option<Cow<'_, str>>, SpankError> {
match self.get_option_value_os(name) {
Some(val) => Ok(Some(os_value_to_str(val)?)),
None => Ok(None),
}
}
/// Returns the value set for the option `name` as an OsString
///
/// If the option was specified multiple times, it returns the last value
/// provided.
///
/// *WARNING*: If options have not yet been processed (e.g in init callbacks
/// or all slurmd contexts), this function will always return None.
///
/// *WARNING*: This function always returns None for options which don't
/// take values (flag options created without takes_value()) no matter whether
/// they were used or not. To check whether a flag was set, use
/// get_option_count.
pub fn get_option_value_os(&self, name: &str) -> Option<Cow<'_, OsStr>> {
match self.context() {
Ok(Context::JobScript) => self
.getopt_os(name)
.ok() // We made sure call from the correct context
.map(|opt| opt.map(Cow::from))
.unwrap_or(None),
_ => {
if let Some(Some(ref value)) = self.opt_cache.values.get(name) {
Some(Cow::from(value))
} else {
None
}
}
}
}
/// Returns whether an option was set
///
/// Use this function to process flag options.
///
/// *WARNING*: If options have not yet been processed (e.g in init callbacks
/// or all slurmd contexts), this function will always return false.
pub fn is_option_set(&self, name: &str) -> bool {
match self.context() {
Ok(Context::JobScript) => self.getopt_os(name).is_ok(),
_ => self.opt_cache.values.get(name).is_some(),
}
}
spank_item_getter!(
/// Returns the primary group id
job_gid,
SpankItem::JobGid,
gid_t
);
spank_item_getter!(
/// Returns the user id
job_uid,
SpankItem::JobUid,
uid_t
);
spank_item_getter!(
/// Returns the job id
job_id,
SpankItem::JobId,
u32
);
spank_item_getter!(
/// Returns the job step id
job_stepid,
SpankItem::JobStepid,
u32
);
spank_item_getter!(
/// Returns the total number of nodes in job
job_nnodes,
SpankItem::JobNnodes,
u32
);
spank_item_getter!(
/// Returns the relative id of this node
job_nodeid,
SpankItem::JobNodeid,
u32
);
spank_item_getter!(
/// Returns the number of local tasks
job_local_task_count,
SpankItem::JobLocalTaskCount,
u32
);
spank_item_getter!(
/// Returns the total number of tasks in job
job_total_task_count,
SpankItem::JobTotalTaskCount,
u32
);
spank_item_getter!(
/// Returns the number of CPUs used by this job
job_ncpus,
SpankItem::JobNcpus,
u16
);
/// Returns the job command arguments as Vec<&str>. An error is returned if
/// arguments are not valid UTF-8
pub fn job_argv(&self) -> Result<Vec<&str>, SpankError> {
self.job_argv_c()
.and_then(|(argc, argv)| self.argv_to_vec(argc, argv))
}
/// Returns the job command args as Vec<&OsStr>
pub fn job_argv_os(&self) -> Result<Vec<&OsStr>, SpankError> {
self.job_argv_c()
.map(|(argc, argv)| self.argv_to_vec_os(argc, argv))
}
fn job_argv_c(&self) -> Result<(usize, *const *const c_char), SpankError> {
let mut argc: c_int = 0;
let mut argv: *const *const c_char = ptr::null_mut();
let argc_ptr: *mut c_int = &mut argc;
let argv_ptr: *mut *const *const c_char = &mut argv;
match unsafe {
spank_sys::spank_get_item(self.spank, SpankItem::JobArgv.into(), argc_ptr, argv_ptr)
} {
spank_sys::ESPANK_SUCCESS => {
if argv.is_null() {
panic!("spank_get_item returned unexpected NULL ptr");
}
Ok((argc as usize, argv))
}
e => Err(SpankError::from_spank("spank_get_item", e)),
}
}
/// Returns the job environment variables as a Vec<&str>. An error is
/// returned if variables are not valid UTF-8
pub fn job_env(&self) -> Result<Vec<&str>, SpankError> {
self.job_env_c()
.and_then(|(argc, argv)| self.argv_to_vec(argc, argv))
}
/// Returns the job environment variables as an array of Vec<&OsStr>
pub fn job_env_os(&self) -> Result<Vec<&OsStr>, SpankError> {
self.job_env_c()
.map(|(argc, argv)| self.argv_to_vec_os(argc, argv))
}
fn job_env_c(&self) -> Result<(usize, *const *const c_char), SpankError> {
let mut envv: *const *const c_char = ptr::null_mut();
match unsafe { spank_sys::spank_get_item(self.spank, SpankItem::JobEnv.into(), &mut envv) }
{
spank_sys::ESPANK_SUCCESS => {
if envv.is_null() {
panic!("spank_get_item returned unexpected NULL ptr")
}
let mut argc: isize = 0;
while !unsafe { *envv.offset(argc) }.is_null() {
argc += 1;
}
Ok((argc as usize, envv))
}
e => Err(SpankError::from_spank("spank_get_item", e)),
}
}
spank_item_getter!(
/// Returns the local task id
task_id,
SpankItem::TaskId,
c_int
);
spank_item_getter!(
/// Returns the global task id
task_global_id,
SpankItem::TaskGlobalId,
u32
);
spank_item_getter!(
/// Returns the exit status of the current task if exited
task_exit_status,
SpankItem::TaskExitStatus,
c_int
);
spank_item_getter!(
/// Returns the pid of the current task
task_pid,
SpankItem::TaskPid,
pid_t
);
spank_item_getter!(
/// Returns the the global task id corresponding to the specified pid
pid_to_global_id,
SpankItem::JobPidToGlobalId,
pid,
pid_t,
u32
);
spank_item_getter!(
/// Returns the local task id corresponding to the specified pid
pid_to_local_id,
SpankItem::JobPidToLocalId,
pid,
pid_t,
u32
);
spank_item_getter!(
/// Returns the local task id corresponding to the specified global id
local_to_global_id,
SpankItem::JobLocalToGlobalId,
local_id,
u32,
u32
);
spank_item_getter!(
/// Returns the global task id corresponding to the specified local id
global_to_local_id,
SpankItem::JobGlobalToLocalId,
global_id,
u32,
u32
);
/// Returns the list of supplementary gids for the current job
pub fn job_supplementary_gids(&self) -> Result<Vec<gid_t>, SpankError> {
let mut gidc: c_int = 0;
let mut gidv: *const gid_t = ptr::null_mut();
let gidc_ptr: *mut c_int = &mut gidc;
let gidv_ptr: *mut *const gid_t = &mut gidv;
match unsafe {
spank_sys::spank_get_item(
self.spank,
SpankItem::JobSupplementaryGids.into(),
gidv_ptr,
gidc_ptr,
)
} {
spank_sys::ESPANK_SUCCESS => {
Ok(unsafe { slice::from_raw_parts(gidv, gidc as usize) }.to_vec())
}
e => Err(SpankError::from_spank("spank_get_item", e)),
}
}
spank_item_getter!(
/// Returns the current Slurm version
slurm_version,
SpankItem::SlurmVersion,
&str
);
spank_item_getter!(
/// Returns the major release number of Slurm
slurm_version_major,
SpankItem::SlurmVersionMajor,
&str
);
spank_item_getter!(
/// Returns the minor release number of Slurm
slurm_version_minor,
SpankItem::SlurmVersionMinor,
&str
);
spank_item_getter!(
/// Returns the micro release number of Slurm
slurm_version_micro,
SpankItem::SlurmVersionMicro,
&str
);
spank_item_getter!(
/// Returns the number of CPUs allocated per task. Returns 1 if --overcommit option is used
step_cpus_per_task,
SpankItem::StepCpusPerTask,
u64
);
spank_item_getter!(
/// Returns the list of allocated cores for the job
job_alloc_cores,
SpankItem::JobAllocCores,
&str
);
spank_item_getter!(
/// Returns the amount of allocated memory for the job in MB
job_alloc_mem,
SpankItem::JobAllocMem,
u64
);
spank_item_getter!(
/// Returns the list of allocated cores for the step
step_alloc_cores,
SpankItem::StepAllocCores,
&str
);
spank_item_getter!(
/// Returns the amount of allocated memory for the step in MB
step_alloc_mem,
SpankItem::StepAllocMem,
u64
);
spank_item_getter!(
/// Returns the restart count for the job
slurm_restart_count,
SpankItem::SlurmRestartCount,
u32
);
spank_item_getter!(
/// Returns the job array id
job_array_id,
SpankItem::JobArrayId,
u32
);
spank_item_getter!(
/// Returns the job array task id
job_array_task_id,
SpankItem::JobArrayTaskId,
u32
);
}
fn cstring_escape_null(msg: &str) -> CString {
// XXX: We can't deal with NULL characters when passing strings to slurm log
// functions, but how do we expect a plugin author to handle the error if we
// returned one ? We assume they would prefer that we render them as a 0 in
// the logs instead.
let c_safe_msg = msg.split('\u{0000}').collect::<Vec<&str>>().join("0");
// Should never panic as we made sure there is no NULL chars
CString::new(&c_safe_msg as &str).unwrap()
}
/// Log level for SPANK logging functions
pub enum LogLevel {
Error,
Info,
Verbose,
Debug,
Debug2,
Debug3,
}
static FORMAT_STRING: [u8; 3] = *b"%s\0";
/// Log messages through SPANK
pub fn spank_log(level: LogLevel, msg: &str) {
let c_msg = cstring_escape_null(msg);
let c_format_string = FORMAT_STRING.as_ptr() as *const c_char;
match level {
LogLevel::Error => unsafe { spank_sys::slurm_error(c_format_string, c_msg.as_ptr()) },
LogLevel::Info => unsafe { spank_sys::slurm_info(c_format_string, c_msg.as_ptr()) },
LogLevel::Verbose => unsafe { spank_sys::slurm_verbose(c_format_string, c_msg.as_ptr()) },
LogLevel::Debug => unsafe { spank_sys::slurm_debug(c_format_string, c_msg.as_ptr()) },
LogLevel::Debug2 => unsafe { spank_sys::slurm_debug2(c_format_string, c_msg.as_ptr()) },
LogLevel::Debug3 => unsafe { spank_sys::slurm_debug3(c_format_string, c_msg.as_ptr()) },
}
}
pub fn slurm_spank_log(msg: &str) {
let c_msg = cstring_escape_null(msg);
let c_format_string = FORMAT_STRING.as_ptr() as *const c_char;
unsafe { spank_sys::slurm_spank_log(c_format_string, c_msg.as_ptr()) }
}
#[macro_export]
/// Log messages through SPANK at the error level
macro_rules! spank_log_error {
($($arg:tt)*) => ({
$crate::spank_log($crate::LogLevel::Error,&format!($($arg)*));
})
}
#[macro_export]
/// Log messages through SPANK at the info level
macro_rules! spank_log_info {
($($arg:tt)*) => ({
$crate::spank_log($crate::LogLevel::Info, &format!($($arg)*));
})
}
#[macro_export]
/// Log messages through SPANK at the verbose level
macro_rules! spank_log_verbose {
($($arg:tt)*) => ({
$crate::spank_log($crate::LogLevel::Verbose, &format!($($arg)*));
})
}
#[macro_export]
/// Log messages through SPANK at the debug level
macro_rules! spank_log_debug {
($($arg:tt)*) => ({
$crate::spank_log($crate::LogLevel::Debug, &format!($($arg)*));
})
}
#[macro_export]
/// Log messages through SPANK at the debug2 level
macro_rules! spank_log_debug2 {
($($arg:tt)*) => ({
$crate::spank_log($crate::LogLevel::Debug2, &format!($($arg)*));
})
}
#[macro_export]
/// Log messages through SPANK at the debug3 level
macro_rules! spank_log_debug3 {
($($arg:tt)*) => ({
$crate::spank_log($crate::LogLevel::Debug3, &format!($($arg)*));
})
}
#[macro_export]
/// Log messages back to the user at the error level without prepending "error:"
macro_rules! spank_log_user {
($($arg:tt)*) => ({
$crate::slurm_spank_log(&format!($($arg)*));
})
}
// XXX: Slurm should only call us in a sequential and non-reentrant way but Rust
// doesn't know that. The overhead of locking these Mutex at each Slurm callback
// should be negligible and we'll get a clear error if something is called out
// of order by mistake. However this is not ideal because it requires the Plugin
// to be Send which can be restricting. We should probably confirm with Slurm
// devs that all calls are sequential and switch to a static mut or similar.
lazy_static! {
static ref OPTION_CACHE: Mutex<OptionCache> = Mutex::new(OptionCache::default());
static ref PLUGIN: Mutex<Option<Box<dyn Plugin>>> = Mutex::new(None);
}
#[doc(hidden)]
pub fn spank_callback_with_globals<P: Plugin + Default + 'static, F>(func: F) -> c_int
where
F: FnOnce(&mut dyn Plugin, &mut OptionCache, bool) -> Result<(), Box<dyn Error>> + UnwindSafe,
{
let unwind_res = catch_unwind(|| {
// These Mutexes should never be contended unless something unreoverable
// happened before
let mut opt_cache = OPTION_CACHE
.try_lock()
.expect("Failed to acquire global options mutex");
let mut plugin_option = PLUGIN
.try_lock()
.expect("Failed to acquire global plugin mutex");
let mut need_setup = false;
let mut plugin = plugin_option.take().unwrap_or_else(|| {
let p = P::default();
need_setup = true;
Box::new(p)
});
let err = match func(plugin.as_mut(), &mut opt_cache, need_setup) {
Ok(()) => 0,
Err(_) => -1,
};
plugin_option.replace(plugin);
err
});
match unwind_res {
Ok(e) => e,
Err(panic) => {
let panic_string = panic
.downcast::<&str>()
.map(|b| b.to_string())
.or_else(|panic| panic.downcast::<String>().map(|s| *s))
.unwrap_or_else(|_| "non-string panic".to_string());
spank_log_error!(
"Caught panic while running spank callback: {}",
panic_string
);
-1
}
}
}
#[no_mangle]
// We pass this callback to process all spank options
// It just stores which options were set in a cache for later retrieval
extern "C" fn spank_option_callback(
val: std::os::raw::c_int,
optarg: *const std::os::raw::c_char,
_remote: std::os::raw::c_int,
) -> std::os::raw::c_int {
// This Mutex should never be contended unless something unrecoverable
// already happened before
let mut opt_cache = OPTION_CACHE
.try_lock()
.expect("Failed to acquire global options mutex");
let name = opt_cache.options.get(val as usize).cloned();
let name = match name {
None => {
spank_log(
LogLevel::Error,
&format!(
"Internal spank-rs error: received unexpected option callback {}",
val
),
);
return -1;
}
Some(name) => name,
};
let optarg = {
if optarg.is_null() {
None
} else {
Some(
std::ffi::OsStr::from_bytes(unsafe { std::ffi::CStr::from_ptr(optarg) }.to_bytes())
.to_os_string(),
)
}
};
opt_cache.values.insert(name, optarg);
0
}
#[doc(hidden)]
// This function only public so that it may be called from the callbacks
// generated by the macro. It should not be called to create handles manually.
pub fn init_spank_handle(
spank: spank_sys::spank_t,
argc: c_int,
argv: *const *const c_char,
opt_cache: &mut OptionCache,
) -> SpankHandle {
SpankHandle {
spank,
argc,
argv,
opt_cache,
}
}
#[doc(hidden)]
// This function is only public so that it may be called from the callbacks
// generated by the macro.
pub fn make_cb_span(id: &str, cb: &str, ctx: &str, task_id: Option<u32>) -> tracing::Span {
if let Some(task_id) = task_id {
span!(tracing::Level::DEBUG, "spank", id, cb, ctx, task_id)
} else {
span!(tracing::Level::DEBUG, "spank", id, cb, ctx)
}
}
pub use spank_sys::SLURM_VERSION_NUMBER;
#[macro_export]
/// Export a Plugin to make it available to the Slurm plugin loader
///
/// # Example
///
///```rust,no_run
///SPANK_PLUGIN!(b"renice", SLURM_VERSION_NUMBER, SpankRenice);
///```
///
/// The first argument is the name of the SPANK plugin. It has to be provided as a byte string.
///
/// The second argument is the Slurm version for which the plugin is built, specified in hexadecimal (2 digits per version component).
/// The SLURM_VERSION_NUMBER constant can be used. It refers to the version of the Slurm headers that the plugin is built against.
///
/// The last argument is a struct for which the Plugin trait has been implemented
macro_rules! SPANK_PLUGIN {
($spank_name:literal, $spank_version:expr, $spank_ty:ty) => {
const fn byte_string_size<T>(_: &T) -> usize {
std::mem::size_of::<T>()
}
#[no_mangle]
pub static plugin_name: [u8; byte_string_size($spank_name) + 1] =
*$crate::byte_strings::concat_bytes!($spank_name, "\0");
#[no_mangle]
pub static mut plugin_type: [u8; 6] = *b"spank\0";
#[no_mangle]
pub static plugin_version: std::os::raw::c_uint = $spank_version;
fn _check_spank_trait<T: Plugin>() {}
fn _t() {
_check_spank_trait::<$spank_ty>()
}
macro_rules! spank_hook {
($c_spank_cb:ident, $rust_spank_cb:ident) => {
#[no_mangle]
#[doc(hidden)]
pub extern "C" fn $c_spank_cb(
spank: $crate::spank_sys::spank_t,
ac: std::os::raw::c_int,
argv: *const *const std::os::raw::c_char,
) -> std::os::raw::c_int {
$crate::spank_callback_with_globals::<$spank_ty, _>(
|plugin, options, need_setup| {
let mut spank = $crate::init_spank_handle(spank, ac, argv, options);
if need_setup {
plugin.setup(&mut spank).map_err(|e| {
plugin.report_error(e.as_ref());
e
})?;
}
let context = spank
.context()
.map(|ctx| format!("{:?}", ctx))
.unwrap_or("Error".to_string());
let tid = spank.task_global_id().ok();
let span = $crate::make_cb_span(
std::ffi::CStr::from_bytes_with_nul(&plugin_name)?.to_str()?,
stringify!($c_spank_cb),
&context,
tid,
);
let _guard = span.enter();
unsafe {
plugin.$rust_spank_cb(&mut spank).map_err(|e| {
plugin.report_error(e.as_ref());
e
})
}
},
)
}
};
}
spank_hook!(slurm_spank_init, init);
spank_hook!(slurm_spank_job_prolog, job_prolog);
spank_hook!(slurm_spank_init_post_opt, init_post_opt);
spank_hook!(slurm_spank_local_user_init, local_user_init);
spank_hook!(slurm_spank_user_init, user_init);
spank_hook!(slurm_spank_task_init_privileged, task_init_privileged);
spank_hook!(slurm_spank_task_init, task_init);
spank_hook!(slurm_spank_task_post_fork, task_post_fork);
spank_hook!(slurm_spank_task_exit, task_exit);
spank_hook!(slurm_spank_job_epilog, job_epilog);
spank_hook!(slurm_spank_slurmd_exit, slurmd_exit);
spank_hook!(slurm_spank_exit, exit);
};
}
/// Implement this trait to create a SPANK plugin
/// # Safety
/// The task callbacks (task_init, task_init_privileged, ...) are called from child processes which slurmstepd creates by forking itself.
/// This may lead to deadlocks or other issues if the Rust plugin is multi-threaded (see <https://man7.org/linux/man-pages/man7/signal-safety.7.html>)
#[allow(unused_variables)]
pub unsafe trait Plugin: Send {
/// Called just after plugins are loaded.
///
/// In remote context, this is just after job step is initialized. This
/// function is called before any plugin option processing.
fn init(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called at the same time as the job prolog.
///
/// If this function returns an error and the SPANK plugin that contains it
/// is required in the plugstack.conf, the node that this is run on will be
/// drained.
fn job_prolog(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called at the same point as slurm_spank_init, but after all user options
/// to the plugin have been processed.
///
/// The reason that the init and init_post_opt callbacks are separated is so
/// that plugins can process system-wide options specified in plugstack.conf
/// in the init callback, then process user options, and finally take some
/// action in slurm_spank_init_post_opt if necessary. In the case of a
/// heterogeneous job, slurm_spank_init is invoked once per job component.
fn init_post_opt(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called in local (srun) context only after all options have been
/// processed.
///
/// This is called after the job ID and step IDs are available. This happens
/// in srun after the allocation is made, but before tasks are launched.
fn local_user_init(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called after privileges are temporarily dropped. (remote context only)
fn user_init(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called for each task just after fork, but before all elevated privileges
/// are dropped. (remote context only)
fn task_init_privileged(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called for each task just before execve (2).
///
/// If you are restricting memory with cgroups, memory allocated here will be
/// in the job's cgroup. (remote context only)
fn task_init(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called for each task from parent process after fork (2) is complete.
///
/// Due to the fact that slurmd does not exec any tasks until all tasks
/// have completed fork (2), this call is guaranteed to run before the user
/// task is executed. (remote context only)
fn task_post_fork(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called for each task as its exit status is collected by Slurm. (remote context only)
fn task_exit(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called at the same time as the job epilog.
///
/// If this function returns an error and the SPANK plugin that contains it
/// is required in the plugstack.conf, the node that this is run on will be
/// drained.
fn job_epilog(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called in slurmd when the daemon is shut down.
fn slurmd_exit(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called once just before slurmstepd exits in remote context. In local
/// context, called before srun exits.
fn exit(&mut self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
Ok(())
}
/// Called each time an Err Result is returned from a SPANK callback
///
/// The default implementation logs errors through SPANK along with their
/// causes.
fn report_error(&self, error: &dyn Error) {
// TODO: use error iterators once they're stable
let mut report = error.to_string();
let mut error = error;
while let Some(source) = error.source() {
report.push_str(&format!(": {}", source));
error = source;
}
error!("{}", &report);
}
/// Called before the first callback from SPANK
///
/// The default implementation configures a tracing Subscriber.
fn setup(&self, spank: &mut SpankHandle) -> Result<(), Box<dyn Error>> {
let default_level = match spank.context()? {
Context::Local | Context::Allocator => "error",
_ => "debug",
};
let filter_layer =
EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new(default_level));
let fmt_layer = layer()
.with_ansi(false)
.event_format(SpankTraceFormatter {})
.with_writer(SpankTraceWriter {});
Registry::default()
.with(filter_layer)
.with(fmt_layer)
.init();
Ok(())
}
}
struct SpankTraceFormatter;
impl<S, N> FormatEvent<S, N> for SpankTraceFormatter
where
S: Subscriber + for<'a> LookupSpan<'a>,
N: for<'a> FormatFields<'a> + 'static,
{
fn format_event(
&self,
ctx: &FmtContext<'_, S, N>,
mut writer: Writer,
event: &Event<'_>,
) -> fmt::Result {
// Write level
let level = *event.metadata().level();
write!(writer, "{}: ", level.to_string().to_lowercase())?;
// Write spans and fields of each span
ctx.visit_spans(|span| {
write!(writer, "{}", span.name())?;
let ext = span.extensions();
// `FormattedFields` is a a formatted representation of the span's
// fields, which is stored in its extensions by the `fmt` layer's
// `new_span` method. The fields will have been formatted
// by the same field formatter that's provided to the event
// formatter in the `FmtContext`.
let fields = &ext
.get::<FormattedFields<N>>()
.expect("will never be `None`");
if !fields.is_empty() {
write!(writer, "{{{}}}", fields)?;
}
write!(writer, ": ")?;
Ok(())
})?;
// Write fields on the event
ctx.field_format().format_fields(writer, event)
}
}
struct SpankTraceWriter {}
impl<'a> tracing_subscriber::fmt::MakeWriter<'a> for SpankTraceWriter {
type Writer = Self;
fn make_writer(&self) -> Self::Writer {
Self {}
}
}
impl std::io::Write for SpankTraceWriter {
fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
let c_string = CString::new(buf)
.map_err(|e| std::io::Error::new(std::io::ErrorKind::InvalidInput, e.to_string()))?;
unsafe {
spank_sys::slurm_info(FORMAT_STRING.as_ptr() as *const c_char, c_string.as_ptr())
};
Ok(buf.len())
}
fn flush(&mut self) -> std::io::Result<()> {
Ok(())
}
}
#[derive(Debug, Copy, Clone, PartialEq, IntoPrimitive)]
#[repr(u32)]
enum SpankItem {
JobGid = spank_sys::spank_item_S_JOB_GID,
JobUid = spank_sys::spank_item_S_JOB_UID,
JobId = spank_sys::spank_item_S_JOB_ID,
JobStepid = spank_sys::spank_item_S_JOB_STEPID,
JobNnodes = spank_sys::spank_item_S_JOB_NNODES,
JobNodeid = spank_sys::spank_item_S_JOB_NODEID,
JobLocalTaskCount = spank_sys::spank_item_S_JOB_LOCAL_TASK_COUNT,
JobTotalTaskCount = spank_sys::spank_item_S_JOB_TOTAL_TASK_COUNT,
JobNcpus = spank_sys::spank_item_S_JOB_NCPUS,
JobArgv = spank_sys::spank_item_S_JOB_ARGV,
JobEnv = spank_sys::spank_item_S_JOB_ENV,
TaskId = spank_sys::spank_item_S_TASK_ID,
TaskGlobalId = spank_sys::spank_item_S_TASK_GLOBAL_ID,
TaskExitStatus = spank_sys::spank_item_S_TASK_EXIT_STATUS,
TaskPid = spank_sys::spank_item_S_TASK_PID,
JobPidToGlobalId = spank_sys::spank_item_S_JOB_PID_TO_GLOBAL_ID,
JobPidToLocalId = spank_sys::spank_item_S_JOB_PID_TO_LOCAL_ID,
JobLocalToGlobalId = spank_sys::spank_item_S_JOB_LOCAL_TO_GLOBAL_ID,
JobGlobalToLocalId = spank_sys::spank_item_S_JOB_GLOBAL_TO_LOCAL_ID,
JobSupplementaryGids = spank_sys::spank_item_S_JOB_SUPPLEMENTARY_GIDS,
SlurmVersion = spank_sys::spank_item_S_SLURM_VERSION,
SlurmVersionMajor = spank_sys::spank_item_S_SLURM_VERSION_MAJOR,
SlurmVersionMinor = spank_sys::spank_item_S_SLURM_VERSION_MINOR,
SlurmVersionMicro = spank_sys::spank_item_S_SLURM_VERSION_MICRO,
StepCpusPerTask = spank_sys::spank_item_S_STEP_CPUS_PER_TASK,
JobAllocCores = spank_sys::spank_item_S_JOB_ALLOC_CORES,
JobAllocMem = spank_sys::spank_item_S_JOB_ALLOC_MEM,
StepAllocCores = spank_sys::spank_item_S_STEP_ALLOC_CORES,
StepAllocMem = spank_sys::spank_item_S_STEP_ALLOC_MEM,
SlurmRestartCount = spank_sys::spank_item_S_SLURM_RESTART_COUNT,
JobArrayId = spank_sys::spank_item_S_JOB_ARRAY_ID,
JobArrayTaskId = spank_sys::spank_item_S_JOB_ARRAY_TASK_ID,
}
#[derive(Debug, Copy, Clone, PartialEq, Eq, IntoPrimitive, FromPrimitive)]
#[repr(u32)]
/// Errors returned by the underlying SPANK API
pub enum SpankApiError {
#[num_enum(default)]
Generic = spank_sys::slurm_err_t_ESPANK_ERROR,
BadArg = spank_sys::slurm_err_t_ESPANK_BAD_ARG,
NotTask = spank_sys::slurm_err_t_ESPANK_NOT_TASK,
EnvExists = spank_sys::slurm_err_t_ESPANK_ENV_EXISTS,
EnvNotExist = spank_sys::slurm_err_t_ESPANK_ENV_NOEXIST,
NoSpace = spank_sys::slurm_err_t_ESPANK_NOSPACE,
NotRemote = spank_sys::slurm_err_t_ESPANK_NOT_REMOTE,
NoExist = spank_sys::slurm_err_t_ESPANK_NOEXIST,
NotExecd = spank_sys::slurm_err_t_ESPANK_NOT_EXECD,
NotAvail = spank_sys::slurm_err_t_ESPANK_NOT_AVAIL,
NotLocal = spank_sys::slurm_err_t_ESPANK_NOT_LOCAL,
}
impl Error for SpankApiError {}
impl fmt::Display for SpankApiError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let cerr = unsafe { CStr::from_ptr(spank_sys::spank_strerror(*self as u32)) };
if let Ok(err) = cerr.to_str() {
write!(f, "{}", err)
} else {
write!(f, "Unknown Error")
}
}
}
impl Error for SpankError {}
#[derive(Debug, Clone)]
/// Main Error enum for interfaces provided by this crate
pub enum SpankError {
CStringError(String),
EnvExists(String),
IdNotFound(u32),
PidNotFound(pid_t),
SpankAPI(String, SpankApiError),
Utf8Error(String),
Overflow(usize),
}
impl SpankError {
fn from_os_str(s: &OsStr) -> SpankError {
SpankError::Utf8Error(s.to_string_lossy().to_string())
}
fn from_str(s: &str) -> SpankError {
SpankError::CStringError(s.to_string())
}
fn from_cstr(s: &CStr) -> SpankError {
SpankError::CStringError(s.to_string_lossy().to_string())
}
fn from_spank(name: &str, err: u32) -> SpankError {
SpankError::SpankAPI(name.to_owned(), SpankApiError::from(err))
}
fn from_spank_item(name: &str, arg: SpankItem, err: u32) -> SpankError {
SpankError::SpankAPI(format!("{}({:?})", name, arg), SpankApiError::from(err))
}
}
trait FromNoExist<T> {
fn from_noexist(v: T) -> SpankError;
}
impl FromNoExist<u32> for SpankError {
fn from_noexist(v: u32) -> SpankError {
SpankError::IdNotFound(v)
}
}
impl FromNoExist<pid_t> for SpankError {
fn from_noexist(v: pid_t) -> SpankError {
SpankError::PidNotFound(v)
}
}
impl fmt::Display for SpankError {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
SpankError::SpankAPI(name, e) => {
write!(f, "Error calling SPANK API function {}: {}", name, e)
}
SpankError::Utf8Error(s) => write!(f, "Cannot parse {} as UTF-8", s),
SpankError::CStringError(s) => {
write!(f, "String {} cannot be converted to a C string", s)
}
SpankError::EnvExists(s) => write!(
f,
"Environment variable {} exists and overwrite was not set",
s
),
SpankError::PidNotFound(p) => write!(f, "Could not find pid {}", p),
SpankError::IdNotFound(i) => write!(f, "Could not find id {}", i),
SpankError::Overflow(u) => write!(f, "Integer overflow: {}", u),
}
}
}
#[derive(Debug, Copy, Clone, PartialEq, Eq, IntoPrimitive, TryFromPrimitive)]
#[repr(u32)]
/// Context in which a plugin is loaded during a Slurm job
pub enum Context {
// We dont represent error here, as errors are better embedded in Results
Local = spank_sys::spank_context_S_CTX_LOCAL,
Remote = spank_sys::spank_context_S_CTX_REMOTE,
Allocator = spank_sys::spank_context_S_CTX_ALLOCATOR,
Slurmd = spank_sys::spank_context_S_CTX_SLURMD,
JobScript = spank_sys::spank_context_S_CTX_JOB_SCRIPT,
}
/// SPANK plugin command-line option that can be registered with
/// SpankHandle::register_option
pub struct SpankOption {
name: String,
arginfo: Option<String>,
usage: Option<String>,
}
impl SpankOption {
pub fn new(name: &str) -> Self {
SpankOption {
name: name.to_string(),
arginfo: None,
usage: None,
}
}
pub fn usage(mut self, usage: &str) -> Self {
self.usage = Some(usage.to_string());
self
}
pub fn takes_value(mut self, arg_name: &str) -> Self {
self.arginfo = Some(arg_name.to_string());
self
}
}