[AIX] support read global symbol of big archive

Reviewers: James Henderson, Fangrui Song

Differential Revision: https://reviews.llvm.org/D124865

1 files changed, 58 insertions, 3 deletions

diff --git a/llvm/lib/Object/Archive.cpp b/llvm/lib/Object/Archive.cpp
index ad03f9c..1dffe00 100644
--- a/llvm/lib/Object/Archive.cpp
+++ b/llvm/lib/Object/Archive.cpp
@@ -965,14 +965,15 @@ StringRef Archive::Symbol::getName() const {
 Expected<Archive::Child> Archive::Symbol::getMember() const {
   const char *Buf = Parent->getSymbolTable().begin();
   const char *Offsets = Buf;
-  if (Parent->kind() == K_GNU64 || Parent->kind() == K_DARWIN64)
+  if (Parent->kind() == K_GNU64 || Parent->kind() == K_DARWIN64 ||
+      Parent->kind() == K_AIXBIG)
     Offsets += sizeof(uint64_t);
   else
     Offsets += sizeof(uint32_t);
   uint64_t Offset = 0;
   if (Parent->kind() == K_GNU) {
     Offset = read32be(Offsets + SymbolIndex * 4);
-  } else if (Parent->kind() == K_GNU64) {
+  } else if (Parent->kind() == K_GNU64 || Parent->kind() == K_AIXBIG) {
     Offset = read64be(Offsets + SymbolIndex * 8);
   } else if (Parent->kind() == K_BSD) {
     // The SymbolIndex is an index into the ranlib structs that start at
@@ -1105,6 +1106,8 @@ Archive::symbol_iterator Archive::symbol_begin() const {
     // Skip the byte count of the string table.
     buf += sizeof(uint64_t);
     buf += ran_strx;
+  } else if (kind() == K_AIXBIG) {
+    buf = getStringTable().begin();
   } else {
     uint32_t member_count = 0;
     uint32_t symbol_count = 0;
@@ -1127,7 +1130,7 @@ uint32_t Archive::getNumberOfSymbols() const {
   const char *buf = getSymbolTable().begin();
   if (kind() == K_GNU)
     return read32be(buf);
-  if (kind() == K_GNU64)
+  if (kind() == K_GNU64 || kind() == K_AIXBIG)
     return read64be(buf);
   if (kind() == K_BSD)
     return read32le(buf) / 8;
@@ -1180,6 +1183,58 @@ BigArchive::BigArchive(MemoryBufferRef Source, Error &Err)
     Err = malformedError("malformed AIX big archive: last member offset \"" +
                          RawOffset + "\" is not a number");
 
+  // Calculate the global symbol table.
+  uint64_t GlobSymOffset = 0;
+  RawOffset = getFieldRawString(ArFixLenHdr->GlobSymOffset);
+  if (RawOffset.getAsInteger(10, GlobSymOffset))
+    // TODO: add test case.
+    Err = malformedError(
+        "malformed AIX big archive: global symbol table offset \"" + RawOffset +
+        "\" is not a number");
+
+  if (Err)
+    return;
+
+  if (GlobSymOffset > 0) {
+    uint64_t BufferSize = Data.getBufferSize();
+    uint64_t GlobalSymTblContentOffset =
+        GlobSymOffset + sizeof(BigArMemHdrType);
+    if (GlobalSymTblContentOffset > BufferSize) {
+      Err = malformedError("global symbol table header at offset 0x" +
+                           Twine::utohexstr(GlobSymOffset) + " and size 0x" +
+                           Twine::utohexstr(sizeof(BigArMemHdrType)) +
+                           " goes past the end of file");
+      return;
+    }
+
+    const char *GlobSymTblLoc = Data.getBufferStart() + GlobSymOffset;
+    const BigArMemHdrType *GlobalSymHdr =
+        reinterpret_cast<const BigArMemHdrType *>(GlobSymTblLoc);
+    RawOffset = getFieldRawString(GlobalSymHdr->Size);
+    uint64_t Size;
+    if (RawOffset.getAsInteger(10, Size)) {
+      // TODO: add test case.
+      Err = malformedError(
+          "malformed AIX big archive: global symbol table size \"" + RawOffset +
+          "\" is not a number");
+      return;
+    }
+    if (GlobalSymTblContentOffset + Size > BufferSize) {
+      Err = malformedError("global symbol table content at offset 0x" +
+                           Twine::utohexstr(GlobalSymTblContentOffset) +
+                           " and size 0x" + Twine::utohexstr(Size) +
+                           " goes past the end of file");
+      return;
+    }
+    SymbolTable = StringRef(GlobSymTblLoc + sizeof(BigArMemHdrType), Size);
+    unsigned SymNum = getNumberOfSymbols();
+    unsigned SymOffsetsSize = 8 * (SymNum + 1);
+    uint64_t SymbolTableStringSize = Size - SymOffsetsSize;
+    StringTable =
+        StringRef(GlobSymTblLoc + sizeof(BigArMemHdrType) + SymOffsetsSize,
+                  SymbolTableStringSize);
+  }
+
   child_iterator I = child_begin(Err, false);
   if (Err)
     return;