implement dropsection

Author: axic

libchisel/src/dropsection.rs

@@ -1,6 +1,9 @@
+use std::collections::HashMap;
+use std::error::Error;
+
 use parity_wasm::elements::{Module, Section};
 
-use super::{ChiselModule, ModuleError, ModuleKind, ModuleTranslator};
+use super::{ChiselModule, ModuleConfig, ModuleError, ModuleKind, ModuleTranslator};
 
 /// Enum on which ModuleTranslator is implemented.
 pub enum DropSection {
@@ -29,6 +32,36 @@ impl<'a> ChiselModule<'a> for DropSection {
     }
 }
 
+impl From<std::num::ParseIntError> for ModuleError {
+    fn from(error: std::num::ParseIntError) -> Self {
+        ModuleError::Custom(error.description().to_string())
+    }
+}
+
+impl ModuleConfig for DropSection {
+    fn with_defaults() -> Result<Self, ModuleError> {
+        Err(ModuleError::NotSupported)
+    }
+
+    fn with_config(config: &HashMap<String, String>) -> Result<Self, ModuleError> {
+        if let Some((key, val)) = config.iter().next() {
+            return match key.as_str() {
+                "names" => Ok(DropSection::NamesSection),
+                "custom_by_name" => Ok(DropSection::CustomSectionByName(val.clone())),
+                "custom_by_index" => {
+                    Ok(DropSection::CustomSectionByIndex(str::parse::<usize>(val)?))
+                }
+                "unknown_by_index" => Ok(DropSection::UnknownSectionByIndex(str::parse::<usize>(
+                    val,
+                )?)),
+                _ => Err(ModuleError::NotSupported),
+            };
+        } else {
+            Err(ModuleError::NotFound)
+        }
+    }
+}
+
 // TODO: consider upstreaming this
 fn custom_section_index_for(module: &Module, name: &str) -> Option<usize> {
     module.sections().iter().position(|e| match e {

libchisel/src/fromwat.rs

@@ -1,7 +1,7 @@
 use parity_wasm::elements::Module;
 use wabt::Wat2Wasm;
 
-use super::{ChiselModule, ModuleCreator, ModuleError, ModuleKind};
+use super::{ChiselModule, ModuleConfig, ModuleCreator, ModuleError, ModuleKind};
 
 /// Struct on which ModuleCreator is implemented.
 pub struct FromWat<'a> {