Skip to main content

wasmtime_cli_flags/
lib.rs

1//! Contains the common Wasmtime command line interface (CLI) flags.
2
3use anyhow::{Context, Result};
4use clap::Parser;
5use serde::Deserialize;
6use std::{
7    fmt, fs,
8    path::{Path, PathBuf},
9    time::Duration,
10};
11use wasmtime::Config;
12
13pub mod opt;
14
15#[cfg(feature = "logging")]
16fn init_file_per_thread_logger(prefix: &'static str) {
17    file_per_thread_logger::initialize(prefix);
18    file_per_thread_logger::allow_uninitialized();
19
20    // Extending behavior of default spawner:
21    // https://docs.rs/rayon/1.1.0/rayon/struct.ThreadPoolBuilder.html#method.spawn_handler
22    // Source code says DefaultSpawner is implementation detail and
23    // shouldn't be used directly.
24    #[cfg(feature = "parallel-compilation")]
25    rayon::ThreadPoolBuilder::new()
26        .spawn_handler(move |thread| {
27            let mut b = std::thread::Builder::new();
28            if let Some(name) = thread.name() {
29                b = b.name(name.to_owned());
30            }
31            if let Some(stack_size) = thread.stack_size() {
32                b = b.stack_size(stack_size);
33            }
34            b.spawn(move || {
35                file_per_thread_logger::initialize(prefix);
36                thread.run()
37            })?;
38            Ok(())
39        })
40        .build_global()
41        .unwrap();
42}
43
44wasmtime_option_group! {
45    #[derive(PartialEq, Clone, Deserialize)]
46    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
47    pub struct OptimizeOptions {
48        /// Optimization level of generated code (0-2, s; default: 2)
49        #[serde(default)]
50        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
51        pub opt_level: Option<wasmtime::OptLevel>,
52
53        /// Register allocator algorithm choice.
54        #[serde(default)]
55        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
56        pub regalloc_algorithm: Option<wasmtime::RegallocAlgorithm>,
57
58        /// Do not allow Wasm linear memories to move in the host process's
59        /// address space.
60        pub memory_may_move: Option<bool>,
61
62        /// Initial virtual memory allocation size for memories.
63        pub memory_reservation: Option<u64>,
64
65        /// Bytes to reserve at the end of linear memory for growth into.
66        pub memory_reservation_for_growth: Option<u64>,
67
68        /// Size, in bytes, of guard pages for linear memories.
69        pub memory_guard_size: Option<u64>,
70
71        /// Indicates whether an unmapped region of memory is placed before all
72        /// linear memories.
73        pub guard_before_linear_memory: Option<bool>,
74
75        /// Whether to initialize tables lazily, so that instantiation is
76        /// fast but indirect calls are a little slower. If no, tables are
77        /// initialized eagerly from any active element segments that apply to
78        /// them during instantiation. (default: yes)
79        pub table_lazy_init: Option<bool>,
80
81        /// Enable the pooling allocator, in place of the on-demand allocator.
82        pub pooling_allocator: Option<bool>,
83
84        /// The number of decommits to do per batch. A batch size of 1
85        /// effectively disables decommit batching. (default: 1)
86        pub pooling_decommit_batch_size: Option<usize>,
87
88        /// How many bytes to keep resident between instantiations for the
89        /// pooling allocator in linear memories.
90        pub pooling_memory_keep_resident: Option<usize>,
91
92        /// How many bytes to keep resident between instantiations for the
93        /// pooling allocator in tables.
94        pub pooling_table_keep_resident: Option<usize>,
95
96        /// Enable memory protection keys for the pooling allocator; this can
97        /// optimize the size of memory slots.
98        #[serde(default)]
99        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
100        pub pooling_memory_protection_keys: Option<wasmtime::MpkEnabled>,
101
102        /// Sets an upper limit on how many memory protection keys (MPK) Wasmtime
103        /// will use. (default: 16)
104        pub pooling_max_memory_protection_keys: Option<usize>,
105
106        /// Configure attempting to initialize linear memory via a
107        /// copy-on-write mapping (default: yes)
108        pub memory_init_cow: Option<bool>,
109
110        /// Threshold below which CoW images are guaranteed to be used and be
111        /// dense.
112        pub memory_guaranteed_dense_image_size: Option<u64>,
113
114        /// The maximum number of WebAssembly instances which can be created
115        /// with the pooling allocator.
116        pub pooling_total_core_instances: Option<u32>,
117
118        /// The maximum number of WebAssembly components which can be created
119        /// with the pooling allocator.
120        pub pooling_total_component_instances: Option<u32>,
121
122        /// The maximum number of WebAssembly memories which can be created with
123        /// the pooling allocator.
124        pub pooling_total_memories: Option<u32>,
125
126        /// The maximum number of WebAssembly tables which can be created with
127        /// the pooling allocator.
128        pub pooling_total_tables: Option<u32>,
129
130        /// The maximum number of WebAssembly stacks which can be created with
131        /// the pooling allocator.
132        pub pooling_total_stacks: Option<u32>,
133
134        /// The maximum runtime size of each linear memory in the pooling
135        /// allocator, in bytes.
136        pub pooling_max_memory_size: Option<usize>,
137
138        /// The maximum table elements for any table defined in a module when
139        /// using the pooling allocator.
140        pub pooling_table_elements: Option<usize>,
141
142        /// The maximum size, in bytes, allocated for a core instance's metadata
143        /// when using the pooling allocator.
144        pub pooling_max_core_instance_size: Option<usize>,
145
146        /// Configures the maximum number of "unused warm slots" to retain in the
147        /// pooling allocator. (default: 100)
148        pub pooling_max_unused_warm_slots: Option<u32>,
149
150        /// How much memory, in bytes, to keep resident for async stacks allocated
151        /// with the pooling allocator. (default: 0)
152        pub pooling_async_stack_keep_resident: Option<usize>,
153
154        /// The maximum size, in bytes, allocated for a component instance's
155        /// `VMComponentContext` metadata. (default: 1MiB)
156        pub pooling_max_component_instance_size: Option<usize>,
157
158        /// The maximum number of core instances a single component may contain
159        /// (default is unlimited).
160        pub pooling_max_core_instances_per_component: Option<u32>,
161
162        /// The maximum number of Wasm linear memories that a single component may
163        /// transitively contain (default is unlimited).
164        pub pooling_max_memories_per_component: Option<u32>,
165
166        /// The maximum number of tables that a single component may transitively
167        /// contain (default is unlimited).
168        pub pooling_max_tables_per_component: Option<u32>,
169
170        /// The maximum number of defined tables for a core module. (default: 1)
171        pub pooling_max_tables_per_module: Option<u32>,
172
173        /// The maximum number of defined linear memories for a module. (default: 1)
174        pub pooling_max_memories_per_module: Option<u32>,
175
176        /// The maximum number of concurrent GC heaps supported. (default: 1000)
177        pub pooling_total_gc_heaps: Option<u32>,
178
179        /// Enable or disable the use of host signal handlers for traps.
180        pub signals_based_traps: Option<bool>,
181
182        /// DEPRECATED: Use `-Cmemory-guard-size=N` instead.
183        pub dynamic_memory_guard_size: Option<u64>,
184
185        /// DEPRECATED: Use `-Cmemory-guard-size=N` instead.
186        pub static_memory_guard_size: Option<u64>,
187
188        /// DEPRECATED: Use `-Cmemory-may-move` instead.
189        pub static_memory_forced: Option<bool>,
190
191        /// DEPRECATED: Use `-Cmemory-reservation=N` instead.
192        pub static_memory_maximum_size: Option<u64>,
193
194        /// DEPRECATED: Use `-Cmemory-reservation-for-growth=N` instead.
195        pub dynamic_memory_reserved_for_growth: Option<u64>,
196    }
197
198    enum Optimize {
199        ...
200    }
201}
202
203wasmtime_option_group! {
204    #[derive(PartialEq, Clone, Deserialize)]
205    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
206    pub struct CodegenOptions {
207        /// Either `cranelift` or `winch`.
208        ///
209        /// Currently only `cranelift` and `winch` are supported, but not all
210        /// builds of Wasmtime have both built in.
211        #[serde(default)]
212        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
213        pub compiler: Option<wasmtime::Strategy>,
214        /// Which garbage collector to use: `drc` or `null`.
215        ///
216        /// `drc` is the deferred reference-counting collector.
217        ///
218        /// `null` is the null garbage collector, which does not collect any
219        /// garbage.
220        ///
221        /// Note that not all builds of Wasmtime will have support for garbage
222        /// collection included.
223        #[serde(default)]
224        #[serde(deserialize_with = "crate::opt::cli_parse_wrapper")]
225        pub collector: Option<wasmtime::Collector>,
226        /// Enable Cranelift's internal debug verifier (expensive)
227        pub cranelift_debug_verifier: Option<bool>,
228        /// Whether or not to enable caching of compiled modules.
229        pub cache: Option<bool>,
230        /// Configuration for compiled module caching.
231        pub cache_config: Option<String>,
232        /// Whether or not to enable parallel compilation of modules.
233        pub parallel_compilation: Option<bool>,
234        /// Whether to enable proof-carrying code (PCC)-based validation.
235        pub pcc: Option<bool>,
236        /// Controls whether native unwind information is present in compiled
237        /// object files.
238        pub native_unwind_info: Option<bool>,
239
240        /// Whether to perform function inlining during compilation.
241        pub inlining: Option<bool>,
242
243        #[prefixed = "cranelift"]
244        #[serde(default)]
245        /// Set a cranelift-specific option. Use `wasmtime settings` to see
246        /// all.
247        pub cranelift: Vec<(String, Option<String>)>,
248    }
249
250    enum Codegen {
251        ...
252    }
253}
254
255wasmtime_option_group! {
256    #[derive(PartialEq, Clone, Deserialize)]
257    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
258    pub struct DebugOptions {
259        /// Enable generation of DWARF debug information in compiled code.
260        pub debug_info: Option<bool>,
261        /// Configure whether compiled code can map native addresses to wasm.
262        pub address_map: Option<bool>,
263        /// Configure whether logging is enabled.
264        pub logging: Option<bool>,
265        /// Configure whether logs are emitted to files
266        pub log_to_files: Option<bool>,
267        /// Enable coredump generation to this file after a WebAssembly trap.
268        pub coredump: Option<String>,
269    }
270
271    enum Debug {
272        ...
273    }
274}
275
276wasmtime_option_group! {
277    #[derive(PartialEq, Clone, Deserialize)]
278    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
279    pub struct WasmOptions {
280        /// Enable canonicalization of all NaN values.
281        pub nan_canonicalization: Option<bool>,
282        /// Enable execution fuel with N units fuel, trapping after running out
283        /// of fuel.
284        ///
285        /// Most WebAssembly instructions consume 1 unit of fuel. Some
286        /// instructions, such as `nop`, `drop`, `block`, and `loop`, consume 0
287        /// units, as any execution cost associated with them involves other
288        /// instructions which do consume fuel.
289        pub fuel: Option<u64>,
290        /// Yield when a global epoch counter changes, allowing for async
291        /// operation without blocking the executor.
292        pub epoch_interruption: Option<bool>,
293        /// Maximum stack size, in bytes, that wasm is allowed to consume before a
294        /// stack overflow is reported.
295        pub max_wasm_stack: Option<usize>,
296        /// Stack size, in bytes, that will be allocated for async stacks.
297        ///
298        /// Note that this must be larger than `max-wasm-stack` and the
299        /// difference between the two is how much stack the host has to execute
300        /// on.
301        pub async_stack_size: Option<usize>,
302        /// Configures whether or not stacks used for async futures are zeroed
303        /// before (re)use as a defense-in-depth mechanism. (default: false)
304        pub async_stack_zeroing: Option<bool>,
305        /// Allow unknown exports when running commands.
306        pub unknown_exports_allow: Option<bool>,
307        /// Allow the main module to import unknown functions, using an
308        /// implementation that immediately traps, when running commands.
309        pub unknown_imports_trap: Option<bool>,
310        /// Allow the main module to import unknown functions, using an
311        /// implementation that returns default values, when running commands.
312        pub unknown_imports_default: Option<bool>,
313        /// Enables memory error checking. (see wmemcheck.md for more info)
314        pub wmemcheck: Option<bool>,
315        /// Maximum size, in bytes, that a linear memory is allowed to reach.
316        ///
317        /// Growth beyond this limit will cause `memory.grow` instructions in
318        /// WebAssembly modules to return -1 and fail.
319        pub max_memory_size: Option<usize>,
320        /// Maximum size, in table elements, that a table is allowed to reach.
321        pub max_table_elements: Option<usize>,
322        /// Maximum number of WebAssembly instances allowed to be created.
323        pub max_instances: Option<usize>,
324        /// Maximum number of WebAssembly tables allowed to be created.
325        pub max_tables: Option<usize>,
326        /// Maximum number of WebAssembly linear memories allowed to be created.
327        pub max_memories: Option<usize>,
328        /// Force a trap to be raised on `memory.grow` and `table.grow` failure
329        /// instead of returning -1 from these instructions.
330        ///
331        /// This is not necessarily a spec-compliant option to enable but can be
332        /// useful for tracking down a backtrace of what is requesting so much
333        /// memory, for example.
334        pub trap_on_grow_failure: Option<bool>,
335        /// Maximum execution time of wasm code before timing out (1, 2s, 100ms, etc)
336        pub timeout: Option<Duration>,
337        /// Configures support for all WebAssembly proposals implemented.
338        pub all_proposals: Option<bool>,
339        /// Configure support for the bulk memory proposal.
340        pub bulk_memory: Option<bool>,
341        /// Configure support for the multi-memory proposal.
342        pub multi_memory: Option<bool>,
343        /// Configure support for the multi-value proposal.
344        pub multi_value: Option<bool>,
345        /// Configure support for the reference-types proposal.
346        pub reference_types: Option<bool>,
347        /// Configure support for the simd proposal.
348        pub simd: Option<bool>,
349        /// Configure support for the relaxed-simd proposal.
350        pub relaxed_simd: Option<bool>,
351        /// Configure forcing deterministic and host-independent behavior of
352        /// the relaxed-simd instructions.
353        ///
354        /// By default these instructions may have architecture-specific behavior as
355        /// allowed by the specification, but this can be used to force the behavior
356        /// of these instructions to match the deterministic behavior classified in
357        /// the specification. Note that enabling this option may come at a
358        /// performance cost.
359        pub relaxed_simd_deterministic: Option<bool>,
360        /// Configure support for the tail-call proposal.
361        pub tail_call: Option<bool>,
362        /// Configure support for the threads proposal.
363        pub threads: Option<bool>,
364        /// Configure support for the shared-everything-threads proposal.
365        pub shared_everything_threads: Option<bool>,
366        /// Configure support for the memory64 proposal.
367        pub memory64: Option<bool>,
368        /// Configure support for the component-model proposal.
369        pub component_model: Option<bool>,
370        /// Component model support for async lifting/lowering.
371        pub component_model_async: Option<bool>,
372        /// Component model support for async lifting/lowering: this corresponds
373        /// to the 🚝 emoji in the component model specification.
374        pub component_model_async_builtins: Option<bool>,
375        /// Component model support for async lifting/lowering: this corresponds
376        /// to the 🚟 emoji in the component model specification.
377        pub component_model_async_stackful: Option<bool>,
378        /// Component model support for `error-context`: this corresponds
379        /// to the 📝 emoji in the component model specification.
380        pub component_model_error_context: Option<bool>,
381        /// GC support in the component model: this corresponds to the 🛸 emoji
382        /// in the component model specification.
383        pub component_model_gc: Option<bool>,
384        /// Configure support for the function-references proposal.
385        pub function_references: Option<bool>,
386        /// Configure support for the stack-switching proposal.
387        pub stack_switching: Option<bool>,
388        /// Configure support for the GC proposal.
389        pub gc: Option<bool>,
390        /// Configure support for the custom-page-sizes proposal.
391        pub custom_page_sizes: Option<bool>,
392        /// Configure support for the wide-arithmetic proposal.
393        pub wide_arithmetic: Option<bool>,
394        /// Configure support for the extended-const proposal.
395        pub extended_const: Option<bool>,
396        /// Configure support for the exceptions proposal.
397        pub exceptions: Option<bool>,
398        /// DEPRECATED: Configure support for the legacy exceptions proposal.
399        pub legacy_exceptions: Option<bool>,
400    }
401
402    enum Wasm {
403        ...
404    }
405}
406
407wasmtime_option_group! {
408    #[derive(PartialEq, Clone, Deserialize)]
409    #[serde(rename_all = "kebab-case", deny_unknown_fields)]
410    pub struct WasiOptions {
411        /// Enable support for WASI CLI APIs, including filesystems, sockets, clocks, and random.
412        pub cli: Option<bool>,
413        /// Enable WASI APIs marked as: @unstable(feature = cli-exit-with-code)
414        pub cli_exit_with_code: Option<bool>,
415        /// Deprecated alias for `cli`
416        pub common: Option<bool>,
417        /// Enable support for WASI neural network imports (experimental)
418        pub nn: Option<bool>,
419        /// Enable support for WASI threading imports (experimental). Implies preview2=false.
420        pub threads: Option<bool>,
421        /// Enable support for WASI HTTP imports
422        pub http: Option<bool>,
423        /// Number of distinct write calls to the outgoing body's output-stream
424        /// that the implementation will buffer.
425        /// Default: 1.
426        pub http_outgoing_body_buffer_chunks: Option<usize>,
427        /// Maximum size allowed in a write call to the outgoing body's output-stream.
428        /// Default: 1024 * 1024.
429        pub http_outgoing_body_chunk_size: Option<usize>,
430        /// Enable support for WASI config imports (experimental)
431        pub config: Option<bool>,
432        /// Enable support for WASI key-value imports (experimental)
433        pub keyvalue: Option<bool>,
434        /// Inherit environment variables and file descriptors following the
435        /// systemd listen fd specification (UNIX only) (legacy wasip1
436        /// implementation only)
437        pub listenfd: Option<bool>,
438        /// Grant access to the given TCP listen socket (experimental, legacy
439        /// wasip1 implementation only)
440        #[serde(default)]
441        pub tcplisten: Vec<String>,
442        /// Enable support for WASI TLS (Transport Layer Security) imports (experimental)
443        pub tls: Option<bool>,
444        /// Implement WASI Preview1 using new Preview2 implementation (true, default) or legacy
445        /// implementation (false)
446        pub preview2: Option<bool>,
447        /// Pre-load machine learning graphs (i.e., models) for use by wasi-nn.
448        ///
449        /// Each use of the flag will preload a ML model from the host directory
450        /// using the given model encoding. The model will be mapped to the
451        /// directory name: e.g., `--wasi-nn-graph openvino:/foo/bar` will preload
452        /// an OpenVINO model named `bar`. Note that which model encodings are
453        /// available is dependent on the backends implemented in the
454        /// `wasmtime_wasi_nn` crate.
455        #[serde(skip)]
456        pub nn_graph: Vec<WasiNnGraph>,
457        /// Flag for WASI preview2 to inherit the host's network within the
458        /// guest so it has full access to all addresses/ports/etc.
459        pub inherit_network: Option<bool>,
460        /// Indicates whether `wasi:sockets/ip-name-lookup` is enabled or not.
461        pub allow_ip_name_lookup: Option<bool>,
462        /// Indicates whether `wasi:sockets` TCP support is enabled or not.
463        pub tcp: Option<bool>,
464        /// Indicates whether `wasi:sockets` UDP support is enabled or not.
465        pub udp: Option<bool>,
466        /// Enable WASI APIs marked as: @unstable(feature = network-error-code)
467        pub network_error_code: Option<bool>,
468        /// Allows imports from the `wasi_unstable` core wasm module.
469        pub preview0: Option<bool>,
470        /// Inherit all environment variables from the parent process.
471        ///
472        /// This option can be further overwritten with `--env` flags.
473        pub inherit_env: Option<bool>,
474        /// Pass a wasi config variable to the program.
475        #[serde(skip)]
476        pub config_var: Vec<KeyValuePair>,
477        /// Preset data for the In-Memory provider of WASI key-value API.
478        #[serde(skip)]
479        pub keyvalue_in_memory_data: Vec<KeyValuePair>,
480        /// Maximum resources the guest is allowed to create simultaneously.
481        pub max_resources: Option<usize>,
482        /// Fuel to use for all hostcalls to limit guest<->host data transfer.
483        pub hostcall_fuel: Option<usize>,
484        /// Maximum value, in bytes, for a wasi-random 0.2
485        /// `get{,-insecure}-random-bytes` `len` parameter. Calls with a value
486        /// exceeding this limit will trap.
487        pub max_random_size: Option<u64>,
488        /// Maximum value, in bytes, for the contents of a wasi-http 0.2
489        /// `fields` resource (aka `headers` and `trailers`). `fields` methods
490        /// which cause the contents to exceed this size limit will trap.
491        pub max_http_fields_size: Option<usize>,
492    }
493
494    enum Wasi {
495        ...
496    }
497}
498
499#[derive(Debug, Clone, PartialEq)]
500pub struct WasiNnGraph {
501    pub format: String,
502    pub dir: String,
503}
504
505#[derive(Debug, Clone, PartialEq)]
506pub struct KeyValuePair {
507    pub key: String,
508    pub value: String,
509}
510
511/// Common options for commands that translate WebAssembly modules
512#[derive(Parser, Clone, Deserialize)]
513#[serde(deny_unknown_fields)]
514pub struct CommonOptions {
515    // These options groups are used to parse `-O` and such options but aren't
516    // the raw form consumed by the CLI. Instead they're pushed into the `pub`
517    // fields below as part of the `configure` method.
518    //
519    // Ideally clap would support `pub opts: OptimizeOptions` and parse directly
520    // into that but it does not appear to do so for multiple `-O` flags for
521    // now.
522    /// Optimization and tuning related options for wasm performance, `-O help` to
523    /// see all.
524    #[arg(short = 'O', long = "optimize", value_name = "KEY[=VAL[,..]]")]
525    #[serde(skip)]
526    opts_raw: Vec<opt::CommaSeparated<Optimize>>,
527
528    /// Codegen-related configuration options, `-C help` to see all.
529    #[arg(short = 'C', long = "codegen", value_name = "KEY[=VAL[,..]]")]
530    #[serde(skip)]
531    codegen_raw: Vec<opt::CommaSeparated<Codegen>>,
532
533    /// Debug-related configuration options, `-D help` to see all.
534    #[arg(short = 'D', long = "debug", value_name = "KEY[=VAL[,..]]")]
535    #[serde(skip)]
536    debug_raw: Vec<opt::CommaSeparated<Debug>>,
537
538    /// Options for configuring semantic execution of WebAssembly, `-W help` to see
539    /// all.
540    #[arg(short = 'W', long = "wasm", value_name = "KEY[=VAL[,..]]")]
541    #[serde(skip)]
542    wasm_raw: Vec<opt::CommaSeparated<Wasm>>,
543
544    /// Options for configuring WASI and its proposals, `-S help` to see all.
545    #[arg(short = 'S', long = "wasi", value_name = "KEY[=VAL[,..]]")]
546    #[serde(skip)]
547    wasi_raw: Vec<opt::CommaSeparated<Wasi>>,
548
549    // These fields are filled in by the `configure` method below via the
550    // options parsed from the CLI above. This is what the CLI should use.
551    #[arg(skip)]
552    #[serde(skip)]
553    configured: bool,
554
555    #[arg(skip)]
556    #[serde(rename = "optimize", default)]
557    pub opts: OptimizeOptions,
558
559    #[arg(skip)]
560    #[serde(rename = "codegen", default)]
561    pub codegen: CodegenOptions,
562
563    #[arg(skip)]
564    #[serde(rename = "debug", default)]
565    pub debug: DebugOptions,
566
567    #[arg(skip)]
568    #[serde(rename = "wasm", default)]
569    pub wasm: WasmOptions,
570
571    #[arg(skip)]
572    #[serde(rename = "wasi", default)]
573    pub wasi: WasiOptions,
574
575    /// The target triple; default is the host triple
576    #[arg(long, value_name = "TARGET")]
577    #[serde(skip)]
578    pub target: Option<String>,
579
580    /// Use the specified TOML configuration file.
581    /// This TOML configuration file can provide same configuration options as the
582    /// `--optimize`, `--codgen`, `--debug`, `--wasm`, `--wasi` CLI options, with a couple exceptions.
583    ///
584    /// Additional options specified on the command line will take precedent over options loaded from
585    /// this TOML file.
586    #[arg(long = "config", value_name = "FILE")]
587    #[serde(skip)]
588    pub config: Option<PathBuf>,
589}
590
591macro_rules! match_feature {
592    (
593        [$feat:tt : $config:expr]
594        $val:ident => $e:expr,
595        $p:pat => err,
596    ) => {
597        #[cfg(feature = $feat)]
598        {
599            if let Some($val) = $config {
600                $e;
601            }
602        }
603        #[cfg(not(feature = $feat))]
604        {
605            if let Some($p) = $config {
606                anyhow::bail!(concat!("support for ", $feat, " disabled at compile time"));
607            }
608        }
609    };
610}
611
612impl CommonOptions {
613    /// Creates a blank new set of [`CommonOptions`] that can be configured.
614    pub fn new() -> CommonOptions {
615        CommonOptions {
616            opts_raw: Vec::new(),
617            codegen_raw: Vec::new(),
618            debug_raw: Vec::new(),
619            wasm_raw: Vec::new(),
620            wasi_raw: Vec::new(),
621            configured: true,
622            opts: Default::default(),
623            codegen: Default::default(),
624            debug: Default::default(),
625            wasm: Default::default(),
626            wasi: Default::default(),
627            target: None,
628            config: None,
629        }
630    }
631
632    fn configure(&mut self) -> Result<()> {
633        if self.configured {
634            return Ok(());
635        }
636        self.configured = true;
637        if let Some(toml_config_path) = &self.config {
638            let toml_options = CommonOptions::from_file(toml_config_path)?;
639            self.opts = toml_options.opts;
640            self.codegen = toml_options.codegen;
641            self.debug = toml_options.debug;
642            self.wasm = toml_options.wasm;
643            self.wasi = toml_options.wasi;
644        }
645        self.opts.configure_with(&self.opts_raw);
646        self.codegen.configure_with(&self.codegen_raw);
647        self.debug.configure_with(&self.debug_raw);
648        self.wasm.configure_with(&self.wasm_raw);
649        self.wasi.configure_with(&self.wasi_raw);
650        Ok(())
651    }
652
653    pub fn init_logging(&mut self) -> Result<()> {
654        self.configure()?;
655        if self.debug.logging == Some(false) {
656            return Ok(());
657        }
658        #[cfg(feature = "logging")]
659        if self.debug.log_to_files == Some(true) {
660            let prefix = "wasmtime.dbg.";
661            init_file_per_thread_logger(prefix);
662        } else {
663            use std::io::IsTerminal;
664            use tracing_subscriber::{EnvFilter, FmtSubscriber};
665            let builder = FmtSubscriber::builder()
666                .with_writer(std::io::stderr)
667                .with_env_filter(EnvFilter::from_env("WASMTIME_LOG"))
668                .with_ansi(std::io::stderr().is_terminal());
669            if std::env::var("WASMTIME_LOG_NO_CONTEXT").is_ok_and(|value| value.eq("1")) {
670                builder
671                    .with_level(false)
672                    .with_target(false)
673                    .without_time()
674                    .init()
675            } else {
676                builder.init();
677            }
678        }
679        #[cfg(not(feature = "logging"))]
680        if self.debug.log_to_files == Some(true) || self.debug.logging == Some(true) {
681            anyhow::bail!("support for logging disabled at compile time");
682        }
683        Ok(())
684    }
685
686    pub fn config(&mut self, pooling_allocator_default: Option<bool>) -> Result<Config> {
687        self.configure()?;
688        let mut config = Config::new();
689
690        match_feature! {
691            ["cranelift" : self.codegen.compiler]
692            strategy => config.strategy(strategy),
693            _ => err,
694        }
695        match_feature! {
696            ["gc" : self.codegen.collector]
697            collector => config.collector(collector),
698            _ => err,
699        }
700        if let Some(target) = &self.target {
701            config.target(target)?;
702        }
703        match_feature! {
704            ["cranelift" : self.codegen.cranelift_debug_verifier]
705            enable => config.cranelift_debug_verifier(enable),
706            true => err,
707        }
708        if let Some(enable) = self.debug.debug_info {
709            config.debug_info(enable);
710        }
711        if self.debug.coredump.is_some() {
712            #[cfg(feature = "coredump")]
713            config.coredump_on_trap(true);
714            #[cfg(not(feature = "coredump"))]
715            anyhow::bail!("support for coredumps disabled at compile time");
716        }
717        match_feature! {
718            ["cranelift" : self.opts.opt_level]
719            level => config.cranelift_opt_level(level),
720            _ => err,
721        }
722        match_feature! {
723            ["cranelift": self.opts.regalloc_algorithm]
724            algo => config.cranelift_regalloc_algorithm(algo),
725            _ => err,
726        }
727        match_feature! {
728            ["cranelift" : self.wasm.nan_canonicalization]
729            enable => config.cranelift_nan_canonicalization(enable),
730            true => err,
731        }
732        match_feature! {
733            ["cranelift" : self.codegen.pcc]
734            enable => config.cranelift_pcc(enable),
735            true => err,
736        }
737
738        self.enable_wasm_features(&mut config)?;
739
740        #[cfg(feature = "cranelift")]
741        for (name, value) in self.codegen.cranelift.iter() {
742            let name = name.replace('-', "_");
743            unsafe {
744                match value {
745                    Some(val) => {
746                        config.cranelift_flag_set(&name, val);
747                    }
748                    None => {
749                        config.cranelift_flag_enable(&name);
750                    }
751                }
752            }
753        }
754        #[cfg(not(feature = "cranelift"))]
755        if !self.codegen.cranelift.is_empty() {
756            anyhow::bail!("support for cranelift disabled at compile time");
757        }
758
759        #[cfg(feature = "cache")]
760        if self.codegen.cache != Some(false) {
761            use wasmtime::Cache;
762            let cache = match &self.codegen.cache_config {
763                Some(path) => Cache::from_file(Some(Path::new(path)))?,
764                None => Cache::from_file(None)?,
765            };
766            config.cache(Some(cache));
767        }
768        #[cfg(not(feature = "cache"))]
769        if self.codegen.cache == Some(true) {
770            anyhow::bail!("support for caching disabled at compile time");
771        }
772
773        match_feature! {
774            ["parallel-compilation" : self.codegen.parallel_compilation]
775            enable => config.parallel_compilation(enable),
776            true => err,
777        }
778
779        let memory_reservation = self
780            .opts
781            .memory_reservation
782            .or(self.opts.static_memory_maximum_size);
783        if let Some(size) = memory_reservation {
784            config.memory_reservation(size);
785        }
786
787        if let Some(enable) = self.opts.static_memory_forced {
788            config.memory_may_move(!enable);
789        }
790        if let Some(enable) = self.opts.memory_may_move {
791            config.memory_may_move(enable);
792        }
793
794        let memory_guard_size = self
795            .opts
796            .static_memory_guard_size
797            .or(self.opts.dynamic_memory_guard_size)
798            .or(self.opts.memory_guard_size);
799        if let Some(size) = memory_guard_size {
800            config.memory_guard_size(size);
801        }
802
803        let mem_for_growth = self
804            .opts
805            .memory_reservation_for_growth
806            .or(self.opts.dynamic_memory_reserved_for_growth);
807        if let Some(size) = mem_for_growth {
808            config.memory_reservation_for_growth(size);
809        }
810        if let Some(enable) = self.opts.guard_before_linear_memory {
811            config.guard_before_linear_memory(enable);
812        }
813        if let Some(enable) = self.opts.table_lazy_init {
814            config.table_lazy_init(enable);
815        }
816
817        // If fuel has been configured, set the `consume fuel` flag on the config.
818        if self.wasm.fuel.is_some() {
819            config.consume_fuel(true);
820        }
821
822        if let Some(enable) = self.wasm.epoch_interruption {
823            config.epoch_interruption(enable);
824        }
825        if let Some(enable) = self.debug.address_map {
826            config.generate_address_map(enable);
827        }
828        if let Some(enable) = self.opts.memory_init_cow {
829            config.memory_init_cow(enable);
830        }
831        if let Some(size) = self.opts.memory_guaranteed_dense_image_size {
832            config.memory_guaranteed_dense_image_size(size);
833        }
834        if let Some(enable) = self.opts.signals_based_traps {
835            config.signals_based_traps(enable);
836        }
837        if let Some(enable) = self.codegen.native_unwind_info {
838            config.native_unwind_info(enable);
839        }
840        if let Some(enable) = self.codegen.inlining {
841            config.compiler_inlining(enable);
842        }
843
844        // async_stack_size enabled by either async or stack-switching, so
845        // cannot directly use match_feature!
846        #[cfg(any(feature = "async", feature = "stack-switching"))]
847        {
848            if let Some(size) = self.wasm.async_stack_size {
849                config.async_stack_size(size);
850            }
851        }
852        #[cfg(not(any(feature = "async", feature = "stack-switching")))]
853        {
854            if let Some(_size) = self.wasm.async_stack_size {
855                anyhow::bail!(concat!(
856                    "support for async/stack-switching disabled at compile time"
857                ));
858            }
859        }
860
861        match_feature! {
862            ["pooling-allocator" : self.opts.pooling_allocator.or(pooling_allocator_default)]
863            enable => {
864                if enable {
865                    let mut cfg = wasmtime::PoolingAllocationConfig::default();
866                    if let Some(size) = self.opts.pooling_memory_keep_resident {
867                        cfg.linear_memory_keep_resident(size);
868                    }
869                    if let Some(size) = self.opts.pooling_table_keep_resident {
870                        cfg.table_keep_resident(size);
871                    }
872                    if let Some(limit) = self.opts.pooling_total_core_instances {
873                        cfg.total_core_instances(limit);
874                    }
875                    if let Some(limit) = self.opts.pooling_total_component_instances {
876                        cfg.total_component_instances(limit);
877                    }
878                    if let Some(limit) = self.opts.pooling_total_memories {
879                        cfg.total_memories(limit);
880                    }
881                    if let Some(limit) = self.opts.pooling_total_tables {
882                        cfg.total_tables(limit);
883                    }
884                    if let Some(limit) = self.opts.pooling_table_elements
885                        .or(self.wasm.max_table_elements)
886                    {
887                        cfg.table_elements(limit);
888                    }
889                    if let Some(limit) = self.opts.pooling_max_core_instance_size {
890                        cfg.max_core_instance_size(limit);
891                    }
892                    match_feature! {
893                        ["async" : self.opts.pooling_total_stacks]
894                        limit => cfg.total_stacks(limit),
895                        _ => err,
896                    }
897                    if let Some(max) = self.opts.pooling_max_memory_size
898                        .or(self.wasm.max_memory_size)
899                    {
900                        cfg.max_memory_size(max);
901                    }
902                    if let Some(size) = self.opts.pooling_decommit_batch_size {
903                        cfg.decommit_batch_size(size);
904                    }
905                    if let Some(max) = self.opts.pooling_max_unused_warm_slots {
906                        cfg.max_unused_warm_slots(max);
907                    }
908                    match_feature! {
909                        ["async" : self.opts.pooling_async_stack_keep_resident]
910                        size => cfg.async_stack_keep_resident(size),
911                        _ => err,
912                    }
913                    if let Some(max) = self.opts.pooling_max_component_instance_size {
914                        cfg.max_component_instance_size(max);
915                    }
916                    if let Some(max) = self.opts.pooling_max_core_instances_per_component {
917                        cfg.max_core_instances_per_component(max);
918                    }
919                    if let Some(max) = self.opts.pooling_max_memories_per_component {
920                        cfg.max_memories_per_component(max);
921                    }
922                    if let Some(max) = self.opts.pooling_max_tables_per_component {
923                        cfg.max_tables_per_component(max);
924                    }
925                    if let Some(max) = self.opts.pooling_max_tables_per_module {
926                        cfg.max_tables_per_module(max);
927                    }
928                    if let Some(max) = self.opts.pooling_max_memories_per_module {
929                        cfg.max_memories_per_module(max);
930                    }
931                    match_feature! {
932                        ["memory-protection-keys" : self.opts.pooling_memory_protection_keys]
933                        enable => cfg.memory_protection_keys(enable),
934                        _ => err,
935                    }
936                    match_feature! {
937                        ["memory-protection-keys" : self.opts.pooling_max_memory_protection_keys]
938                        max => cfg.max_memory_protection_keys(max),
939                        _ => err,
940                    }
941                    match_feature! {
942                        ["gc" : self.opts.pooling_total_gc_heaps]
943                        max => cfg.total_gc_heaps(max),
944                        _ => err,
945                    }
946                    config.allocation_strategy(wasmtime::InstanceAllocationStrategy::Pooling(cfg));
947                }
948            },
949            true => err,
950        }
951
952        if self.opts.pooling_memory_protection_keys.is_some()
953            && !self.opts.pooling_allocator.unwrap_or(false)
954        {
955            anyhow::bail!("memory protection keys require the pooling allocator");
956        }
957
958        if self.opts.pooling_max_memory_protection_keys.is_some()
959            && !self.opts.pooling_memory_protection_keys.is_some()
960        {
961            anyhow::bail!(
962                "max memory protection keys requires memory protection keys to be enabled"
963            );
964        }
965
966        match_feature! {
967            ["async" : self.wasm.async_stack_zeroing]
968            enable => config.async_stack_zeroing(enable),
969            _ => err,
970        }
971
972        if let Some(max) = self.wasm.max_wasm_stack {
973            config.max_wasm_stack(max);
974
975            // If `-Wasync-stack-size` isn't passed then automatically adjust it
976            // to the wasm stack size provided here too. That prevents the need
977            // to pass both when one can generally be inferred from the other.
978            #[cfg(any(feature = "async", feature = "stack-switching"))]
979            if self.wasm.async_stack_size.is_none() {
980                const DEFAULT_HOST_STACK: usize = 512 << 10;
981                config.async_stack_size(max + DEFAULT_HOST_STACK);
982            }
983        }
984
985        if let Some(enable) = self.wasm.relaxed_simd_deterministic {
986            config.relaxed_simd_deterministic(enable);
987        }
988        match_feature! {
989            ["cranelift" : self.wasm.wmemcheck]
990            enable => config.wmemcheck(enable),
991            true => err,
992        }
993
994        Ok(config)
995    }
996
997    pub fn enable_wasm_features(&self, config: &mut Config) -> Result<()> {
998        let all = self.wasm.all_proposals;
999
1000        if let Some(enable) = self.wasm.simd.or(all) {
1001            config.wasm_simd(enable);
1002        }
1003        if let Some(enable) = self.wasm.relaxed_simd.or(all) {
1004            config.wasm_relaxed_simd(enable);
1005        }
1006        if let Some(enable) = self.wasm.bulk_memory.or(all) {
1007            config.wasm_bulk_memory(enable);
1008        }
1009        if let Some(enable) = self.wasm.multi_value.or(all) {
1010            config.wasm_multi_value(enable);
1011        }
1012        if let Some(enable) = self.wasm.tail_call.or(all) {
1013            config.wasm_tail_call(enable);
1014        }
1015        if let Some(enable) = self.wasm.multi_memory.or(all) {
1016            config.wasm_multi_memory(enable);
1017        }
1018        if let Some(enable) = self.wasm.memory64.or(all) {
1019            config.wasm_memory64(enable);
1020        }
1021        if let Some(enable) = self.wasm.stack_switching {
1022            config.wasm_stack_switching(enable);
1023        }
1024        if let Some(enable) = self.wasm.custom_page_sizes.or(all) {
1025            config.wasm_custom_page_sizes(enable);
1026        }
1027        if let Some(enable) = self.wasm.wide_arithmetic.or(all) {
1028            config.wasm_wide_arithmetic(enable);
1029        }
1030        if let Some(enable) = self.wasm.extended_const.or(all) {
1031            config.wasm_extended_const(enable);
1032        }
1033        if let Some(enable) = self.wasm.exceptions.or(all) {
1034            config.wasm_exceptions(enable);
1035        }
1036        if let Some(enable) = self.wasm.legacy_exceptions.or(all) {
1037            #[expect(deprecated, reason = "forwarding CLI flag")]
1038            config.wasm_legacy_exceptions(enable);
1039        }
1040
1041        macro_rules! handle_conditionally_compiled {
1042            ($(($feature:tt, $field:tt, $method:tt))*) => ($(
1043                if let Some(enable) = self.wasm.$field.or(all) {
1044                    #[cfg(feature = $feature)]
1045                    config.$method(enable);
1046                    #[cfg(not(feature = $feature))]
1047                    if enable && all.is_none() {
1048                        anyhow::bail!("support for {} was disabled at compile-time", $feature);
1049                    }
1050                }
1051            )*)
1052        }
1053
1054        handle_conditionally_compiled! {
1055            ("component-model", component_model, wasm_component_model)
1056            ("component-model-async", component_model_async, wasm_component_model_async)
1057            ("component-model-async", component_model_async_builtins, wasm_component_model_async_builtins)
1058            ("component-model-async", component_model_async_stackful, wasm_component_model_async_stackful)
1059            ("component-model", component_model_error_context, wasm_component_model_error_context)
1060            ("threads", threads, wasm_threads)
1061            ("gc", gc, wasm_gc)
1062            ("gc", reference_types, wasm_reference_types)
1063            ("gc", function_references, wasm_function_references)
1064            ("stack-switching", stack_switching, wasm_stack_switching)
1065        }
1066
1067        if let Some(enable) = self.wasm.component_model_gc {
1068            #[cfg(all(feature = "component-model", feature = "gc"))]
1069            config.wasm_component_model_gc(enable);
1070            #[cfg(not(all(feature = "component-model", feature = "gc")))]
1071            if enable && all.is_none() {
1072                anyhow::bail!("support for `component-model-gc` was disabled at compile time")
1073            }
1074        }
1075
1076        Ok(())
1077    }
1078
1079    pub fn from_file<P: AsRef<Path>>(path: P) -> Result<Self> {
1080        let path_ref = path.as_ref();
1081        let file_contents = fs::read_to_string(path_ref)
1082            .with_context(|| format!("failed to read config file: {path_ref:?}"))?;
1083        toml::from_str::<CommonOptions>(&file_contents)
1084            .with_context(|| format!("failed to parse TOML config file {path_ref:?}"))
1085    }
1086}
1087
1088#[cfg(test)]
1089mod tests {
1090    use wasmtime::{OptLevel, RegallocAlgorithm};
1091
1092    use super::*;
1093
1094    #[test]
1095    fn from_toml() {
1096        // empty toml
1097        let empty_toml = "";
1098        let mut common_options: CommonOptions = toml::from_str(empty_toml).unwrap();
1099        common_options.config(None).unwrap();
1100
1101        // basic toml
1102        let basic_toml = r#"
1103            [optimize]
1104            [codegen]
1105            [debug]
1106            [wasm]
1107            [wasi]
1108        "#;
1109        let mut common_options: CommonOptions = toml::from_str(basic_toml).unwrap();
1110        common_options.config(None).unwrap();
1111
1112        // toml with custom deserialization to match CLI flag parsing
1113        for (opt_value, expected) in [
1114            ("0", Some(OptLevel::None)),
1115            ("1", Some(OptLevel::Speed)),
1116            ("2", Some(OptLevel::Speed)),
1117            ("\"s\"", Some(OptLevel::SpeedAndSize)),
1118            ("\"hello\"", None), // should fail
1119            ("3", None),         // should fail
1120        ] {
1121            let toml = format!(
1122                r#"
1123                    [optimize]
1124                    opt-level = {opt_value}
1125                "#,
1126            );
1127            let parsed_opt_level = toml::from_str::<CommonOptions>(&toml)
1128                .ok()
1129                .and_then(|common_options| common_options.opts.opt_level);
1130
1131            assert_eq!(
1132                parsed_opt_level, expected,
1133                "Mismatch for input '{opt_value}'. Parsed: {parsed_opt_level:?}, Expected: {expected:?}"
1134            );
1135        }
1136
1137        // Regalloc algorithm
1138        for (regalloc_value, expected) in [
1139            ("\"backtracking\"", Some(RegallocAlgorithm::Backtracking)),
1140            ("\"hello\"", None), // should fail
1141            ("3", None),         // should fail
1142            ("true", None),      // should fail
1143        ] {
1144            let toml = format!(
1145                r#"
1146                    [optimize]
1147                    regalloc-algorithm = {regalloc_value}
1148                "#,
1149            );
1150            let parsed_regalloc_algorithm = toml::from_str::<CommonOptions>(&toml)
1151                .ok()
1152                .and_then(|common_options| common_options.opts.regalloc_algorithm);
1153            assert_eq!(
1154                parsed_regalloc_algorithm, expected,
1155                "Mismatch for input '{regalloc_value}'. Parsed: {parsed_regalloc_algorithm:?}, Expected: {expected:?}"
1156            );
1157        }
1158
1159        // Strategy
1160        for (strategy_value, expected) in [
1161            ("\"cranelift\"", Some(wasmtime::Strategy::Cranelift)),
1162            ("\"winch\"", Some(wasmtime::Strategy::Winch)),
1163            ("\"hello\"", None), // should fail
1164            ("5", None),         // should fail
1165            ("true", None),      // should fail
1166        ] {
1167            let toml = format!(
1168                r#"
1169                    [codegen]
1170                    compiler = {strategy_value}
1171                "#,
1172            );
1173            let parsed_strategy = toml::from_str::<CommonOptions>(&toml)
1174                .ok()
1175                .and_then(|common_options| common_options.codegen.compiler);
1176            assert_eq!(
1177                parsed_strategy, expected,
1178                "Mismatch for input '{strategy_value}'. Parsed: {parsed_strategy:?}, Expected: {expected:?}",
1179            );
1180        }
1181
1182        // Collector
1183        for (collector_value, expected) in [
1184            (
1185                "\"drc\"",
1186                Some(wasmtime::Collector::DeferredReferenceCounting),
1187            ),
1188            ("\"null\"", Some(wasmtime::Collector::Null)),
1189            ("\"hello\"", None), // should fail
1190            ("5", None),         // should fail
1191            ("true", None),      // should fail
1192        ] {
1193            let toml = format!(
1194                r#"
1195                    [codegen]
1196                    collector = {collector_value}
1197                "#,
1198            );
1199            let parsed_collector = toml::from_str::<CommonOptions>(&toml)
1200                .ok()
1201                .and_then(|common_options| common_options.codegen.collector);
1202            assert_eq!(
1203                parsed_collector, expected,
1204                "Mismatch for input '{collector_value}'. Parsed: {parsed_collector:?}, Expected: {expected:?}",
1205            );
1206        }
1207    }
1208}
1209
1210impl Default for CommonOptions {
1211    fn default() -> CommonOptions {
1212        CommonOptions::new()
1213    }
1214}
1215
1216impl fmt::Display for CommonOptions {
1217    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
1218        let CommonOptions {
1219            codegen_raw,
1220            codegen,
1221            debug_raw,
1222            debug,
1223            opts_raw,
1224            opts,
1225            wasm_raw,
1226            wasm,
1227            wasi_raw,
1228            wasi,
1229            configured,
1230            target,
1231            config,
1232        } = self;
1233        if let Some(target) = target {
1234            write!(f, "--target {target} ")?;
1235        }
1236        if let Some(config) = config {
1237            write!(f, "--config {} ", config.display())?;
1238        }
1239
1240        let codegen_flags;
1241        let opts_flags;
1242        let wasi_flags;
1243        let wasm_flags;
1244        let debug_flags;
1245
1246        if *configured {
1247            codegen_flags = codegen.to_options();
1248            debug_flags = debug.to_options();
1249            wasi_flags = wasi.to_options();
1250            wasm_flags = wasm.to_options();
1251            opts_flags = opts.to_options();
1252        } else {
1253            codegen_flags = codegen_raw
1254                .iter()
1255                .flat_map(|t| t.0.iter())
1256                .cloned()
1257                .collect();
1258            debug_flags = debug_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1259            wasi_flags = wasi_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1260            wasm_flags = wasm_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1261            opts_flags = opts_raw.iter().flat_map(|t| t.0.iter()).cloned().collect();
1262        }
1263
1264        for flag in codegen_flags {
1265            write!(f, "-C{flag} ")?;
1266        }
1267        for flag in opts_flags {
1268            write!(f, "-O{flag} ")?;
1269        }
1270        for flag in wasi_flags {
1271            write!(f, "-S{flag} ")?;
1272        }
1273        for flag in wasm_flags {
1274            write!(f, "-W{flag} ")?;
1275        }
1276        for flag in debug_flags {
1277            write!(f, "-D{flag} ")?;
1278        }
1279
1280        Ok(())
1281    }
1282}