Initial vendor packages

Signed-off-by: Valentin Popov <valentin@popov.link>

1 files changed, 158 insertions, 0 deletions

diff --git a/vendor/object/src/read/macho/relocation.rs b/vendor/object/src/read/macho/relocation.rs
new file mode 100644
index 0000000..709f1a4
--- /dev/null
+++ b/vendor/object/src/read/macho/relocation.rs
@@ -0,0 +1,158 @@
+use core::{fmt, slice};
+
+use crate::endian::Endianness;
+use crate::macho;
+use crate::read::{
+    ReadRef, Relocation, RelocationEncoding, RelocationKind, RelocationTarget, SectionIndex,
+    SymbolIndex,
+};
+
+use super::{MachHeader, MachOFile};
+
+/// An iterator for the relocations in a [`MachOSection32`](super::MachOSection32).
+pub type MachORelocationIterator32<'data, 'file, Endian = Endianness, R = &'data [u8]> =
+    MachORelocationIterator<'data, 'file, macho::MachHeader32<Endian>, R>;
+/// An iterator for the relocations in a [`MachOSection64`](super::MachOSection64).
+pub type MachORelocationIterator64<'data, 'file, Endian = Endianness, R = &'data [u8]> =
+    MachORelocationIterator<'data, 'file, macho::MachHeader64<Endian>, R>;
+
+/// An iterator for the relocations in a [`MachOSection`](super::MachOSection).
+pub struct MachORelocationIterator<'data, 'file, Mach, R = &'data [u8]>
+where
+    Mach: MachHeader,
+    R: ReadRef<'data>,
+{
+    pub(super) file: &'file MachOFile<'data, Mach, R>,
+    pub(super) relocations: slice::Iter<'data, macho::Relocation<Mach::Endian>>,
+}
+
+impl<'data, 'file, Mach, R> Iterator for MachORelocationIterator<'data, 'file, Mach, R>
+where
+    Mach: MachHeader,
+    R: ReadRef<'data>,
+{
+    type Item = (u64, Relocation);
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let mut paired_addend = 0;
+        loop {
+            let reloc = self.relocations.next()?;
+            let endian = self.file.endian;
+            let cputype = self.file.header.cputype(endian);
+            if reloc.r_scattered(endian, cputype) {
+                // FIXME: handle scattered relocations
+                // We need to add `RelocationTarget::Address` for this.
+                continue;
+            }
+            let reloc = reloc.info(self.file.endian);
+            let mut encoding = RelocationEncoding::Generic;
+            let kind = match cputype {
+                macho::CPU_TYPE_ARM => match (reloc.r_type, reloc.r_pcrel) {
+                    (macho::ARM_RELOC_VANILLA, false) => RelocationKind::Absolute,
+                    _ => RelocationKind::MachO {
+                        value: reloc.r_type,
+                        relative: reloc.r_pcrel,
+                    },
+                },
+                macho::CPU_TYPE_ARM64 | macho::CPU_TYPE_ARM64_32 => {
+                    match (reloc.r_type, reloc.r_pcrel) {
+                        (macho::ARM64_RELOC_UNSIGNED, false) => RelocationKind::Absolute,
+                        (macho::ARM64_RELOC_ADDEND, _) => {
+                            paired_addend = i64::from(reloc.r_symbolnum)
+                                .wrapping_shl(64 - 24)
+                                .wrapping_shr(64 - 24);
+                            continue;
+                        }
+                        _ => RelocationKind::MachO {
+                            value: reloc.r_type,
+                            relative: reloc.r_pcrel,
+                        },
+                    }
+                }
+                macho::CPU_TYPE_X86 => match (reloc.r_type, reloc.r_pcrel) {
+                    (macho::GENERIC_RELOC_VANILLA, false) => RelocationKind::Absolute,
+                    _ => RelocationKind::MachO {
+                        value: reloc.r_type,
+                        relative: reloc.r_pcrel,
+                    },
+                },
+                macho::CPU_TYPE_X86_64 => match (reloc.r_type, reloc.r_pcrel) {
+                    (macho::X86_64_RELOC_UNSIGNED, false) => RelocationKind::Absolute,
+                    (macho::X86_64_RELOC_SIGNED, true) => {
+                        encoding = RelocationEncoding::X86RipRelative;
+                        RelocationKind::Relative
+                    }
+                    (macho::X86_64_RELOC_BRANCH, true) => {
+                        encoding = RelocationEncoding::X86Branch;
+                        RelocationKind::Relative
+                    }
+                    (macho::X86_64_RELOC_GOT, true) => RelocationKind::GotRelative,
+                    (macho::X86_64_RELOC_GOT_LOAD, true) => {
+                        encoding = RelocationEncoding::X86RipRelativeMovq;
+                        RelocationKind::GotRelative
+                    }
+                    _ => RelocationKind::MachO {
+                        value: reloc.r_type,
+                        relative: reloc.r_pcrel,
+                    },
+                },
+                _ => RelocationKind::MachO {
+                    value: reloc.r_type,
+                    relative: reloc.r_pcrel,
+                },
+            };
+            let size = 8 << reloc.r_length;
+            let target = if reloc.r_extern {
+                RelocationTarget::Symbol(SymbolIndex(reloc.r_symbolnum as usize))
+            } else {
+                RelocationTarget::Section(SectionIndex(reloc.r_symbolnum as usize))
+            };
+            let implicit_addend = paired_addend == 0;
+            let mut addend = paired_addend;
+            if reloc.r_pcrel {
+                // For PC relative relocations on some architectures, the
+                // addend does not include the offset required due to the
+                // PC being different from the place of the relocation.
+                // This differs from other file formats, so adjust the
+                // addend here to account for this.
+                match cputype {
+                    macho::CPU_TYPE_X86 => {
+                        addend -= 1 << reloc.r_length;
+                    }
+                    macho::CPU_TYPE_X86_64 => {
+                        addend -= 1 << reloc.r_length;
+                        match reloc.r_type {
+                            macho::X86_64_RELOC_SIGNED_1 => addend -= 1,
+                            macho::X86_64_RELOC_SIGNED_2 => addend -= 2,
+                            macho::X86_64_RELOC_SIGNED_4 => addend -= 4,
+                            _ => {}
+                        }
+                    }
+                    // TODO: maybe missing support for some architectures and relocations
+                    _ => {}
+                }
+            }
+            return Some((
+                reloc.r_address as u64,
+                Relocation {
+                    kind,
+                    encoding,
+                    size,
+                    target,
+                    addend,
+                    implicit_addend,
+                },
+            ));
+        }
+    }
+}
+
+impl<'data, 'file, Mach, R> fmt::Debug for MachORelocationIterator<'data, 'file, Mach, R>
+where
+    Mach: MachHeader,
+    R: ReadRef<'data>,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("MachORelocationIterator").finish()
+    }
+}