Make map APIs return an option

switch map() and map_mut() from returning a
`Result` to an `Option` since it's just getting
a value from a Hashmap, and to stay in line with
the Programs API.

Remove `MapError::MapNotFound`

Signed-off-by: Andrew Stoycos <astoycos@redhat.com>

aya-log/src/lib.rs

@@ -90,7 +90,7 @@ impl BpfLogger {
         logger: T,
     ) -> Result<BpfLogger, Error> {
         let logger = Arc::new(logger);
-        let mut logs: AsyncPerfEventArray<_> = bpf.take_map("AYA_LOGS")?.try_into()?;
+        let mut logs: AsyncPerfEventArray<_> = bpf.take_map("AYA_LOGS").unwrap().try_into()?;
 
         for cpu_id in online_cpus().map_err(Error::InvalidOnlineCpu)? {
             let mut buf = logs.open(cpu_id, None)?;

aya/src/bpf.rs

@@ -743,14 +743,8 @@ impl Bpf {
     ///
     /// For more details and examples on maps and their usage, see the [maps module
     /// documentation][crate::maps].
-    ///
-    /// # Errors
-    ///
-    /// Returns [`MapError::MapNotFound`] if the map does not exist.
-    pub fn map(&self, name: &str) -> Result<&Map, MapError> {
-        self.maps.get(name).ok_or_else(|| MapError::MapNotFound {
-            name: name.to_owned(),
-        })
+    pub fn map(&self, name: &str) -> Option<&Map> {
+        self.maps.get(name)
     }
 
     /// Returns a mutable reference to the map with the given name.
@@ -760,16 +754,8 @@ impl Bpf {
     ///
     /// For more details and examples on maps and their usage, see the [maps module
     /// documentation][crate::maps].
-    ///
-    /// # Errors
-    ///
-    /// Returns [`MapError::MapNotFound`] if the map does not exist.
-    pub fn map_mut(&mut self, name: &str) -> Result<&mut Map, MapError> {
-        self.maps
-            .get_mut(name)
-            .ok_or_else(|| MapError::MapNotFound {
-                name: name.to_owned(),
-            })
+    pub fn map_mut(&mut self, name: &str) -> Option<&mut Map> {
+        self.maps.get_mut(name)
     }
 
     /// Takes ownership of a map with the given name.
@@ -785,14 +771,8 @@ impl Bpf {
     ///
     /// For more details and examples on maps and their usage, see the [maps module
     /// documentation][crate::maps].
-    ///
-    /// # Errors
-    ///
-    /// Returns [`MapError::MapNotFound`] if the map does not exist.
-    pub fn take_map(&mut self, name: &str) -> Result<Map, MapError> {
-        self.maps.remove(name).ok_or_else(|| MapError::MapNotFound {
-            name: name.to_owned(),
-        })
+    pub fn take_map(&mut self, name: &str) -> Option<Map> {
+        self.maps.remove(name)
     }
 
     /// An iterator over all the maps.
@@ -808,8 +788,8 @@ impl Bpf {
     /// }
     /// # Ok::<(), aya::BpfError>(())
     /// ```
-    pub fn maps(&self) -> impl Iterator<Item = (&str, Result<&Map, MapError>)> {
-        self.maps.iter().map(|(name, map)| (name.as_str(), Ok(map)))
+    pub fn maps(&self) -> impl Iterator<Item = (&str, &Map)> {
+        self.maps.iter().map(|(name, map)| (name.as_str(), map))
     }
 
     /// Returns a reference to the program with the given name.

aya/src/maps/array/array.rs

@@ -23,7 +23,7 @@ use crate::{
 /// # let mut bpf = aya::Bpf::load(&[])?;
 /// use aya::maps::Array;
 ///
-/// let mut array = Array::try_from(bpf.map_mut("ARRAY")?)?;
+/// let mut array = Array::try_from(bpf.map_mut("ARRAY").unwrap())?;
 /// array.set(1, 42, 0)?;
 /// assert_eq!(array.get(&1, 0)?, 42);
 /// # Ok::<(), aya::BpfError>(())

aya/src/maps/array/per_cpu_array.rs

@@ -33,7 +33,7 @@ use crate::{
 /// use aya::maps::{PerCpuArray, PerCpuValues};
 /// use aya::util::nr_cpus;
 ///
-/// let mut array = PerCpuArray::try_from(bpf.map_mut("ARRAY")?)?;
+/// let mut array = PerCpuArray::try_from(bpf.map_mut("ARRAY").unwrap())?;
 ///
 /// // set array[1] = 42 for all cpus
 /// let nr_cpus = nr_cpus()?;

aya/src/maps/array/program_array.rs

@@ -27,7 +27,7 @@ use crate::{
 /// use aya::maps::ProgramArray;
 /// use aya::programs::CgroupSkb;
 ///
-/// let mut prog_array = ProgramArray::try_from(bpf.take_map("JUMP_TABLE")?)?;
+/// let mut prog_array = ProgramArray::try_from(bpf.take_map("JUMP_TABLE").unwrap())?;
 /// let prog_0: &CgroupSkb = bpf.program("example_prog_0").unwrap().try_into()?;
 /// let prog_0_fd =  prog_0.fd().unwrap();
 /// let prog_1: &CgroupSkb = bpf.program("example_prog_1").unwrap().try_into()?;

aya/src/maps/bloom_filter.rs

@@ -19,7 +19,7 @@ use crate::{
 /// # let mut bpf = aya::Bpf::load(&[])?;
 /// use aya::maps::bloom_filter::BloomFilter;
 ///
-/// let mut bloom_filter = BloomFilter::try_from(bpf.map_mut("BLOOM_FILTER")?)?;
+/// let mut bloom_filter = BloomFilter::try_from(bpf.map_mut("BLOOM_FILTER").unwrap())?;
 ///
 /// bloom_filter.insert(1, 0)?;
 ///

aya/src/maps/hash_map/hash_map.rs

@@ -21,7 +21,7 @@ use crate::{
 /// # let mut bpf = aya::Bpf::load(&[])?;
 /// use aya::maps::HashMap;
 ///
-/// let mut redirect_ports = HashMap::try_from(bpf.map_mut("REDIRECT_PORTS")?)?;
+/// let mut redirect_ports = HashMap::try_from(bpf.map_mut("REDIRECT_PORTS").unwrap())?;
 ///
 /// // redirect port 80 to 8080
 /// redirect_ports.insert(80, 8080, 0);

aya/src/maps/hash_map/per_cpu_hash_map.rs

@@ -31,7 +31,7 @@ use crate::{
 /// const CPU_IDS: u8 = 1;
 /// const WAKEUPS: u8 = 2;
 ///
-/// let mut hm = PerCpuHashMap::<_, u8, u32>::try_from(bpf.map_mut("PER_CPU_STORAGE")?)?;
+/// let mut hm = PerCpuHashMap::<_, u8, u32>::try_from(bpf.map_mut("PER_CPU_STORAGE").unwrap())?;
 /// let cpu_ids = unsafe { hm.get(&CPU_IDS, 0)? };
 /// let wakeups = unsafe { hm.get(&WAKEUPS, 0)? };
 /// for (cpu_id, wakeups) in cpu_ids.iter().zip(wakeups.iter()) {
@@ -107,7 +107,7 @@ impl<T: AsMut<MapData>, K: Pod, V: Pod> PerCpuHashMap<T, K, V> {
     ///
     /// const RETRIES: u8 = 1;
     ///
-    /// let mut hm = PerCpuHashMap::<_, u8, u32>::try_from(bpf.map_mut("PER_CPU_STORAGE")?)?;
+    /// let mut hm = PerCpuHashMap::<_, u8, u32>::try_from(bpf.map_mut("PER_CPU_STORAGE").unwrap())?;
     /// hm.insert(
     ///     RETRIES,
     ///     PerCpuValues::try_from(vec![3u32; nr_cpus()?])?,

aya/src/maps/lpm_trie.rs

@@ -24,7 +24,7 @@ use crate::{
 /// use aya::maps::lpm_trie::{LpmTrie, Key};
 /// use std::net::Ipv4Addr;
 ///
-/// let mut trie = LpmTrie::try_from(bpf.map_mut("LPM_TRIE")?)?;
+/// let mut trie = LpmTrie::try_from(bpf.map_mut("LPM_TRIE").unwrap())?;
 /// let ipaddr = Ipv4Addr::new(8, 8, 8, 8);
 /// // The following represents a key for the "8.8.8.8/16" subnet.
 /// // The first argument - the prefix length - represents how many bytes should be matched against. The second argument is the actual data to be matched.

aya/src/maps/mod.rs

@@ -22,7 +22,7 @@
 //! use aya::maps::SockMap;
 //! use aya::programs::SkMsg;
 //!
-//! let intercept_egress = SockMap::try_from(bpf.map_mut("INTERCEPT_EGRESS")?)?;
+//! let intercept_egress = SockMap::try_from(bpf.map_mut("INTERCEPT_EGRESS").unwrap())?;
 //! let map_fd = intercept_egress.fd()?;
 //! let prog: &mut SkMsg = bpf.program_mut("intercept_egress_packet").unwrap().try_into()?;
 //! prog.load()?;
@@ -90,13 +90,6 @@ pub use stack_trace::StackTraceMap;
 #[derive(Error, Debug)]
 /// Errors occuring from working with Maps
 pub enum MapError {
-    /// Unable to find the map
-    #[error("map `{name}` not found ")]
-    MapNotFound {
-        /// Map name
-        name: String,
-    },
-
     /// Invalid map type encontered
     #[error("invalid map type {map_type}")]
     InvalidMapType {

aya/src/maps/perf/async_perf_event_array.rs

@@ -53,7 +53,7 @@ use crate::maps::{
 /// use tokio::task; // or async_std::task
 ///
 /// // try to convert the PERF_ARRAY map to an AsyncPerfEventArray
-/// let mut perf_array = AsyncPerfEventArray::try_from(bpf.take_map("PERF_ARRAY")?)?;
+/// let mut perf_array = AsyncPerfEventArray::try_from(bpf.take_map("PERF_ARRAY").unwrap())?;
 ///
 /// for cpu_id in online_cpus()? {
 ///     // open a separate perf buffer for each cpu

aya/src/maps/perf/perf_event_array.rs

@@ -110,7 +110,7 @@ impl<T: AsMut<MapData> + AsRef<MapData>> AsRawFd for PerfEventArrayBuffer<T> {
 /// use aya::util::online_cpus;
 /// use bytes::BytesMut;
 ///
-/// let mut perf_array = PerfEventArray::try_from(bpf.map_mut("EVENTS")?)?;
+/// let mut perf_array = PerfEventArray::try_from(bpf.map_mut("EVENTS").unwrap())?;
 ///
 /// // eBPF programs are going to write to the EVENTS perf array, using the id of the CPU they're
 /// // running on as the array index.

aya/src/maps/queue.rs

@@ -21,7 +21,7 @@ use crate::{
 /// # let mut bpf = aya::Bpf::load(&[])?;
 /// use aya::maps::Queue;
 ///
-/// let mut queue = Queue::try_from(bpf.map_mut("ARRAY")?)?;
+/// let mut queue = Queue::try_from(bpf.map_mut("ARRAY").unwrap())?;
 /// queue.push(42, 0)?;
 /// queue.push(43, 0)?;
 /// assert_eq!(queue.pop(0)?, 42);

aya/src/maps/sock/sock_hash.rs

@@ -46,15 +46,15 @@ use crate::{
 /// use aya::maps::SockHash;
 /// use aya::programs::SkMsg;
 ///
-/// let mut intercept_egress = SockHash::<_, u32>::try_from(bpf.map("INTERCEPT_EGRESS")?)?;
+/// let mut intercept_egress = SockHash::<_, u32>::try_from(bpf.map("INTERCEPT_EGRESS").unwrap())?;
 /// let map_fd = intercept_egress.fd()?;
 ///
 /// let prog: &mut SkMsg = bpf.program_mut("intercept_egress_packet").unwrap().try_into()?;
 /// prog.load()?;
 /// prog.attach(map_fd)?;
 ///
 /// let mut client = TcpStream::connect("127.0.0.1:1234")?;
-/// let mut intercept_egress = SockHash::try_from(bpf.map_mut("INTERCEPT_EGRESS")?)?;
+/// let mut intercept_egress = SockHash::try_from(bpf.map_mut("INTERCEPT_EGRESS").unwrap())?;
 ///
 /// intercept_egress.insert(1234, client.as_raw_fd(), 0)?;
 ///

aya/src/maps/sock/sock_map.rs

@@ -30,7 +30,7 @@ use crate::{
 /// use aya::maps::SockMap;
 /// use aya::programs::SkSkb;
 ///
-/// let intercept_ingress = SockMap::try_from(bpf.map("INTERCEPT_INGRESS")?)?;
+/// let intercept_ingress = SockMap::try_from(bpf.map("INTERCEPT_INGRESS").unwrap())?;
 /// let map_fd = intercept_ingress.fd()?;
 ///
 /// let prog: &mut SkSkb = bpf.program_mut("intercept_ingress_packet").unwrap().try_into()?;

aya/src/maps/stack.rs

@@ -21,7 +21,7 @@ use crate::{
 /// # let mut bpf = aya::Bpf::load(&[])?;
 /// use aya::maps::Stack;
 ///
-/// let mut stack = Stack::try_from(bpf.map_mut("STACK")?)?;
+/// let mut stack = Stack::try_from(bpf.map_mut("STACK").unwrap())?;
 /// stack.push(42, 0)?;
 /// stack.push(43, 0)?;
 /// assert_eq!(stack.pop(0)?, 43);

aya/src/maps/stack_trace.rs

@@ -35,7 +35,7 @@ use crate::{
 /// use aya::maps::StackTraceMap;
 /// use aya::util::kernel_symbols;
 ///
-/// let mut stack_traces = StackTraceMap::try_from(bpf.map("STACK_TRACES")?)?;
+/// let mut stack_traces = StackTraceMap::try_from(bpf.map("STACK_TRACES").unwrap())?;
 /// // load kernel symbols from /proc/kallsyms
 /// let ksyms = kernel_symbols()?;
 ///

aya/src/programs/sk_msg.rs

@@ -43,15 +43,15 @@ use crate::{
 /// use aya::maps::SockHash;
 /// use aya::programs::SkMsg;
 ///
-/// let intercept_egress: SockHash<_, u32> = bpf.map("INTERCEPT_EGRESS")?.try_into()?;
+/// let intercept_egress: SockHash<_, u32> = bpf.map("INTERCEPT_EGRESS").unwrap().try_into()?;
 /// let map_fd = intercept_egress.fd()?;
 ///
 /// let prog: &mut SkMsg = bpf.program_mut("intercept_egress_packet").unwrap().try_into()?;
 /// prog.load()?;
 /// prog.attach(map_fd)?;
 ///
 /// let mut client = TcpStream::connect("127.0.0.1:1234")?;
-/// let mut intercept_egress: SockHash<_, u32> = bpf.map_mut("INTERCEPT_EGRESS")?.try_into()?;
+/// let mut intercept_egress: SockHash<_, u32> = bpf.map_mut("INTERCEPT_EGRESS").unwrap().try_into()?;
 ///
 /// intercept_egress.insert(1234, client.as_raw_fd(), 0)?;
 ///

aya/src/programs/sk_skb.rs

@@ -41,7 +41,7 @@ pub enum SkSkbKind {
 /// use aya::maps::SockMap;
 /// use aya::programs::SkSkb;
 ///
-/// let intercept_ingress: SockMap<_> = bpf.map("INTERCEPT_INGRESS")?.try_into()?;
+/// let intercept_ingress: SockMap<_> = bpf.map("INTERCEPT_INGRESS").unwrap().try_into()?;
 /// let map_fd = intercept_ingress.fd()?;
 ///
 /// let prog: &mut SkSkb = bpf.program_mut("intercept_ingress_packet").unwrap().try_into()?;

test/integration-test/src/tests/load.rs

@@ -36,8 +36,8 @@ fn multiple_btf_maps() -> anyhow::Result<()> {
         include_bytes_aligned!("../../../../target/bpfel-unknown-none/debug/multimap-btf.bpf.o");
     let mut bpf = Bpf::load(bytes)?;
 
-    let map_1: Array<_, u64> = bpf.take_map("map_1")?.try_into()?;
-    let map_2: Array<_, u64> = bpf.take_map("map_2")?.try_into()?;
+    let map_1: Array<_, u64> = bpf.take_map("map_1").unwrap().try_into()?;
+    let map_2: Array<_, u64> = bpf.take_map("map_2").unwrap().try_into()?;
 
     let prog: &mut TracePoint = bpf.program_mut("tracepoint").unwrap().try_into().unwrap();
     prog.load().unwrap();