Support reading AIX big archive format (#462)

src/archive.rs

@@ -8,6 +8,9 @@ use crate::pod::Pod;
 /// File identification bytes stored at the beginning of the file.
 pub const MAGIC: [u8; 8] = *b"!<arch>\n";
 
+/// File identification bytes at the beginning of AIX big archive.
+pub const AIX_BIG_MAGIC: [u8; 8] = *b"<bigaf>\n";
+
 /// File identification bytes stored at the beginning of a thin archive.
 ///
 /// A thin archive only contains a symbol table and file names.
@@ -36,4 +39,47 @@ pub struct Header {
     pub terminator: [u8; 2],
 }
 
+/// The header at the start of an AIX big archive member, without name.
+#[derive(Debug, Clone, Copy)]
+#[repr(C)]
+pub struct AixHeader {
+    /// File member size in decimal.
+    pub size: [u8; 20],
+    /// Next member offset in decimal.
+    pub nxtmem: [u8; 20],
+    /// Previous member offset in decimal.
+    pub prvmem: [u8; 20],
+    /// File member date in decimal.
+    pub date: [u8; 12],
+    /// File member user id in decimal.
+    pub uid: [u8; 12],
+    /// File member group id in decimal.
+    pub gid: [u8; 12],
+    /// File member mode in octal.
+    pub mode: [u8; 12],
+    /// File member name length in decimal.
+    pub namlen: [u8; 4],
+}
+
+/// The AIX big archive's fixed length header at file beginning.
+#[derive(Debug, Clone, Copy)]
+#[repr(C)]
+pub struct AIXFileHeader {
+    /// Offset of member table
+    pub memoff: [u8; 20],
+    /// Offset of global symbol table
+    pub gstoff: [u8; 20],
+    /// ffset of global symbol table for 64-bit objects
+    pub gst64off: [u8; 20],
+    /// Offset of first member
+    pub fstmoff: [u8; 20],
+    /// Offset of last member
+    pub lstmoff: [u8; 20],
+    /// Offset of first member on free list
+    pub freeoff: [u8; 20],
+}
+
+
 unsafe_impl_pod!(Header);
+unsafe_impl_pod!(AixHeader);
+unsafe_impl_pod!(AIXFileHeader);