[llvm-ar] Implement the O modifier: display member offsets inside the archive

Since GNU ar 2.31, the 't' operation prints member offsets beside file
names if the 'O' modifier is specified. 'O' is ignored for thin
archives.

Reviewed By: gbreynoo, ruiu

Differential Revision: https://reviews.llvm.org/D69087

llvm-svn: 375106

1 files changed, 22 insertions, 12 deletions

diff --git a/llvm/tools/llvm-ar/llvm-ar.cpp b/llvm/tools/llvm-ar/llvm-ar.cpp
index 6233c60e9bd..c9cf217f768 100644
--- a/llvm/tools/llvm-ar/llvm-ar.cpp
+++ b/llvm/tools/llvm-ar/llvm-ar.cpp
@@ -106,6 +106,7 @@ MODIFIERS:
   [L] - add archive's contents
   [N] - use instance [count] of name
   [o] - preserve original dates
+  [O] - display member offsets
   [P] - use full names when matching (implied for thin archives)
   [s] - create an archive index (cf. ranlib)
   [S] - do not build a symbol table
@@ -187,17 +188,18 @@ enum ArchiveOperation {
 };
 
 // Modifiers to follow operation to vary behavior
-static bool AddAfter = false;        ///< 'a' modifier
-static bool AddBefore = false;       ///< 'b' modifier
-static bool Create = false;          ///< 'c' modifier
-static bool OriginalDates = false;   ///< 'o' modifier
-static bool CompareFullPath = false; ///< 'P' modifier
-static bool OnlyUpdate = false;      ///< 'u' modifier
-static bool Verbose = false;         ///< 'v' modifier
-static bool Symtab = true;           ///< 's' modifier
-static bool Deterministic = true;    ///< 'D' and 'U' modifiers
-static bool Thin = false;            ///< 'T' modifier
-static bool AddLibrary = false;      ///< 'L' modifier
+static bool AddAfter = false;             ///< 'a' modifier
+static bool AddBefore = false;            ///< 'b' modifier
+static bool Create = false;               ///< 'c' modifier
+static bool OriginalDates = false;        ///< 'o' modifier
+static bool DisplayMemberOffsets = false; ///< 'O' modifier
+static bool CompareFullPath = false;      ///< 'P' modifier
+static bool OnlyUpdate = false;           ///< 'u' modifier
+static bool Verbose = false;              ///< 'v' modifier
+static bool Symtab = true;                ///< 's' modifier
+static bool Deterministic = true;         ///< 'D' and 'U' modifiers
+static bool Thin = false;                 ///< 'T' modifier
+static bool AddLibrary = false;           ///< 'L' modifier
 
 // Relative Positional Argument (for insert/move). This variable holds
 // the name of the archive member to which the 'a', 'b' or 'i' modifier
@@ -329,6 +331,9 @@ static ArchiveOperation parseCommandLine() {
     case 'o':
       OriginalDates = true;
       break;
+    case 'O':
+      DisplayMemberOffsets = true;
+      break;
     case 'P':
       CompareFullPath = true;
       break;
@@ -486,8 +491,13 @@ static void doDisplayTable(StringRef Name, const object::Archive::Child &C) {
       if (!ParentDir.empty())
         outs() << sys::path::convert_to_slash(ParentDir) << '/';
     }
+    outs() << Name;
+  } else {
+    outs() << Name;
+    if (DisplayMemberOffsets)
+      outs() << " 0x" << utohexstr(C.getDataOffset(), true);
   }
-  outs() << Name << "\n";
+  outs() << '\n';
 }
 
 static std::string normalizePath(StringRef Path) {