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Plumb both data and address endians through
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@cadmic
cadmic committed May 16, 2024
1 parent aadcb31 commit cb0e073
Showing 1 changed file with 36 additions and 23 deletions.
59 changes: 36 additions & 23 deletions src/util/dwarf.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -491,7 +491,7 @@ where R: BufRead + Seek + ?Sized {
if position >= len {
break;
}
let tags = read_tags(reader, e, include_erased, false)?;
let tags = read_tags(reader, e, e, include_erased, false)?;
for tag in tags {
info.tags.insert(tag.key, tag);
}
Expand Down Expand Up @@ -531,7 +531,8 @@ where R: BufRead + Seek + ?Sized {

fn read_tags<R>(
reader: &mut R,
e: Endian,
data_endian: Endian,
addr_endian: Endian,
include_erased: bool,
is_erased: bool,
) -> Result<Vec<Tag>>
Expand All @@ -540,7 +541,7 @@ where
{
let mut tags = Vec::new();
let position = reader.stream_position()?;
let size = u32::from_reader(reader, e)?;
let size = u32::from_reader(reader, data_endian)?;
if size < 8 {
// Null entry
if size > 4 {
Expand All @@ -556,7 +557,7 @@ where
return Ok(tags);
}

let tag_num = u16::from_reader(reader, e)?;
let tag_num = u16::from_reader(reader, data_endian)?;
let tag = TagKind::try_from(tag_num).context("Unknown DWARF tag type")?;
if tag == TagKind::Padding {
if include_erased {
Expand All @@ -569,7 +570,7 @@ where
let mut attributes = Vec::new();
let mut is_function = false;
while reader.stream_position()? < position + size as u64 {
// peek next two bytes
// Peek next two bytes
let mut buf = [0u8; 2];
reader.read_exact(&mut buf)?;
let attr_tag = u16::from_reader(&mut Cursor::new(&buf), Endian::Little)?;
Expand All @@ -579,7 +580,7 @@ where
break;
}

let attr = read_attribute(reader, Endian::Little)?;
let attr = read_attribute(reader, Endian::Little, addr_endian)?;
if attr.kind == AttributeKind::HighPc {
is_function = true;
}
Expand All @@ -596,7 +597,7 @@ where

// Read the rest of the tags
while reader.stream_position()? < position + size as u64 {
for tag in read_tags(reader, Endian::Little, include_erased, true)? {
for tag in read_tags(reader, Endian::Little, addr_endian, include_erased, true)? {
tags.push(tag);
}
}
Expand All @@ -606,7 +607,7 @@ where
} else {
let mut attributes = Vec::new();
while reader.stream_position()? < position + size as u64 {
attributes.push(read_attribute(reader, e)?);
attributes.push(read_attribute(reader, data_endian, addr_endian)?);
}
tags.push(Tag {
key: position as u32,
Expand Down Expand Up @@ -634,29 +635,35 @@ where R: BufRead + ?Sized {
Ok(str)
}

fn read_attribute<R>(reader: &mut R, e: Endian) -> Result<Attribute>
where R: BufRead + Seek + ?Sized {
let attr_type = u16::from_reader(reader, e)?;
fn read_attribute<R>(
reader: &mut R,
data_endian: Endian,
addr_endian: Endian,
) -> Result<Attribute>
where
R: BufRead + Seek + ?Sized,
{
let attr_type = u16::from_reader(reader, data_endian)?;
let attr = AttributeKind::try_from(attr_type).context("Unknown DWARF attribute type")?;
let form = FormKind::try_from(attr_type & FORM_MASK).context("Unknown DWARF form type")?;
let value = match form {
FormKind::Addr => AttributeValue::Address(u32::from_reader(reader, Endian::Big)?),
FormKind::Ref => AttributeValue::Reference(u32::from_reader(reader, Endian::Big)?),
FormKind::Addr => AttributeValue::Address(u32::from_reader(reader, addr_endian)?),
FormKind::Ref => AttributeValue::Reference(u32::from_reader(reader, addr_endian)?),
FormKind::Block2 => {
let size = u16::from_reader(reader, e)?;
let size = u16::from_reader(reader, data_endian)?;
let mut data = vec![0u8; size as usize];
reader.read_exact(&mut data)?;
AttributeValue::Block(data)
}
FormKind::Block4 => {
let size = u32::from_reader(reader, e)?;
let size = u32::from_reader(reader, data_endian)?;
let mut data = vec![0u8; size as usize];
reader.read_exact(&mut data)?;
AttributeValue::Block(data)
}
FormKind::Data2 => AttributeValue::Data2(u16::from_reader(reader, e)?),
FormKind::Data4 => AttributeValue::Data4(u32::from_reader(reader, e)?),
FormKind::Data8 => AttributeValue::Data8(u64::from_reader(reader, e)?),
FormKind::Data2 => AttributeValue::Data2(u16::from_reader(reader, data_endian)?),
FormKind::Data4 => AttributeValue::Data4(u32::from_reader(reader, data_endian)?),
FormKind::Data8 => AttributeValue::Data8(u64::from_reader(reader, data_endian)?),
FormKind::String => AttributeValue::String(read_string(reader)?),
};
Ok(Attribute { kind: attr, value })
Expand Down Expand Up @@ -2019,9 +2026,9 @@ fn process_array_tag(info: &DwarfInfo, tag: &Tag) -> Result<ArrayType> {
(AttributeKind::Sibling, _) => {}
(AttributeKind::SubscrData, AttributeValue::Block(data)) => {
subscr_data =
Some(process_array_subscript_data(data, info.e).with_context(|| {
format!("Failed to process SubscrData for tag: {:?}", tag)
})?)
Some(process_array_subscript_data(data, info.e, tag.is_erased).with_context(
|| format!("Failed to process SubscrData for tag: {:?}", tag),
)?)
}
(AttributeKind::Ordering, val) => match val {
AttributeValue::Data2(d2) => {
Expand All @@ -2047,7 +2054,11 @@ fn process_array_tag(info: &DwarfInfo, tag: &Tag) -> Result<ArrayType> {
Ok(ArrayType { element_type: Box::from(element_type), dimensions })
}

fn process_array_subscript_data(data: &[u8], e: Endian) -> Result<(Type, Vec<ArrayDimension>)> {
fn process_array_subscript_data(
data: &[u8],
e: Endian,
is_erased: bool,
) -> Result<(Type, Vec<ArrayDimension>)> {
let mut element_type = None;
let mut dimensions = Vec::new();
let mut data = data;
Expand Down Expand Up @@ -2087,7 +2098,9 @@ fn process_array_subscript_data(data: &[u8], e: Endian) -> Result<(Type, Vec<Arr
}
SubscriptFormat::ElementType => {
let mut cursor = Cursor::new(data);
let type_attr = read_attribute(&mut cursor, e)?;
// TODO: is this the right endianness to use for erased tags?
let type_attr =
read_attribute(&mut cursor, if is_erased { Endian::Little } else { e }, e)?;
element_type = Some(process_type(&type_attr, e)?);
data = &data[cursor.position() as usize..];
}
Expand Down

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