Add a -d flag to wasm-tools strip (#791)

No real reason for doing this but when I was thinking about this while
ago I figured it would be easy to strip only some sections vs others as
opposed to only an all-or-nothing toggle.

Cargo.toml

@@ -84,6 +84,7 @@ wasmparser-dump = { workspace = true, optional = true }
 
 # Dependencies of `strip`
 wasm-encoder = { workspace = true, optional = true }
+regex = { version = "1.6.0", optional = true }
 
 # Dependencies of `compose`
 wasm-compose = { workspace = true, optional = true, features = ['cli'] }
@@ -116,5 +117,5 @@ shrink = ['wasm-shrink', 'is_executable']
 mutate = ['wasm-mutate']
 dump = ['wasmparser-dump']
 objdump = ['wasmparser']
-strip = ['wasm-encoder', 'wasmparser']
+strip = ['wasm-encoder', 'wasmparser', 'regex']
 compose = ['wasm-compose']

src/bin/wasm-tools/strip.rs

@@ -13,10 +13,14 @@ pub struct Opts {
     #[clap(flatten)]
     io: wasm_tools::InputOutput,
 
-    /// Strip all custom sections, including the `name` section
+    /// Remove all custom sections, regardless of name.
     #[clap(long, short)]
     all: bool,
 
+    /// Remove custom sections matching the specified regex.
+    #[clap(long, short, value_name = "REGEX")]
+    delete: Vec<String>,
+
     /// Output the text format of WebAssembly instead of the binary format.
     #[clap(short = 't', long)]
     wat: bool,
@@ -25,6 +29,22 @@ pub struct Opts {
 impl Opts {
     pub fn run(&self) -> Result<()> {
         let input = self.io.parse_input_wasm()?;
+        let to_delete = regex::RegexSet::new(self.delete.iter())?;
+
+        let strip_custom_section = |name: &str| {
+            // If explicitly specified, strip everything.
+            if self.all {
+                return true;
+            }
+
+            // If any section was called out by name only delete those sections.
+            if !to_delete.is_empty() {
+                return to_delete.is_match(name);
+            }
+
+            // Finally default strip everything but the `name` section.
+            name != "name"
+        };
 
         let mut module = wasm_encoder::Module::new();
 
@@ -75,15 +95,15 @@ impl Opts {
                 | ComponentImportSection(_)
                 | ComponentExportSection(_) => unimplemented!("component model"),
 
-                CustomSection(c) if c.name() == "name" && !self.all => {
-                    module.section(&RawSection {
-                        id: SectionId::Custom as u8,
-                        data: &input[c.range()],
-                    });
+                CustomSection(c) => {
+                    if !strip_custom_section(c.name()) {
+                        module.section(&RawSection {
+                            id: SectionId::Custom as u8,
+                            data: &input[c.range()],
+                        });
+                    }
                 }
 
-                CustomSection(_) => {}
-
                 UnknownSection {
                     id,
                     contents,