Fix some issues with "AddressSpace"s in core processes.

Populate the "offset" from the start of a file, based on the File note,
and set the inode to be something other than 0 in the case that the file
exists.

Also, because the FileEntry type is only used by the "dead" process,
move it into the .cc file to stop exposing the public headers to it.

Also, previously, vmflags and permissions were aggregated into one
field. After splitting, the local variable used to build up the
permissions remained called "flags". Fix that, and rename it.

Author: peadar

dead.cc

@@ -4,8 +4,61 @@
 
 #include <iostream>
 
+
 namespace pstack::Procman {
 
+namespace {
+
+struct FileEntry {
+    Elf::Off start;
+    Elf::Off end;
+    Elf::Off fileOff;
+};
+
+class FileEntries {
+    FileNoteHeader header;
+    Reader::csptr entries;
+    std::unique_ptr<ReaderArray<FileEntry>> entriesArray;
+    Reader::csptr names;
+
+public:
+    class sentinel { };
+    class iterator {
+        friend class FileEntries;
+        const FileEntries &entries;
+        void fetch();
+        bool fetched = false;
+        size_t nameoff = 0;
+        std::pair<std::string, FileEntry> cur;
+        ReaderArray<FileEntry>::iterator entriesIterator;
+   public:
+        iterator(const FileEntries &entries, ReaderArray<FileEntry>::iterator start);
+        iterator &operator++();
+        std::pair<std::string, FileEntry> operator *() { fetch(); return cur; }
+        bool operator != (const iterator &rhs) const { return entriesIterator != rhs.entriesIterator; }
+        bool operator != (const sentinel &) const { return entriesIterator != entries.entriesArray->end(); }
+    };
+    FileEntries(const Elf::Object &obj) {
+        // find the Notes section.
+        for (auto note : obj.notes()) {
+            if (note.name() == "CORE" && note.type() == NT_FILE) {
+                auto data = note.data();
+                header = data->readObj<FileNoteHeader>(0);
+                entries = data->view("FILE note entries", sizeof header, header.count * sizeof (FileEntry));
+                names = data->view("FILE note names", sizeof header + header.count * sizeof (FileEntry));
+                break;
+            }
+        }
+        if (!entries)
+           entries = std::make_shared<NullReader>();
+        entriesArray = std::make_unique<ReaderArray<FileEntry>>(*entries);
+    }
+    iterator begin() const { return iterator(*this, entriesArray->begin()); }
+    sentinel end() const { return sentinel{}; }
+};
+}
+
+
 CoreProcess::CoreProcess(Context &ctx, Elf::Object::sptr exec, Elf::Object::sptr core)
    : Process(ctx, std::move(exec), std::make_shared<CoreReader>(this, core))
      , prpsinfo{}
@@ -228,20 +281,25 @@ CoreProcess::addressSpace() const {
     for (const auto &hdr : coreImage->getSegments(PT_LOAD)) {
         auto ub = entries.upper_bound(hdr.p_vaddr);
         std::string name;
+        uintmax_t offset = 0;
+        uintmax_t inode = 0;
         if (ub != entries.begin()) {
             --ub;
-            if (ub->first >= hdr.p_vaddr && ub->second.second.end <= hdr.p_vaddr + hdr.p_memsz)
+            if (ub->first >= hdr.p_vaddr && ub->second.second.end <= hdr.p_vaddr + hdr.p_memsz) {
                 name = ub->second.first;
+                offset = ub->second.second.fileOff * getpagesize(); // that's the offset in pages.
+                inode = 1;
+            }
         }
-        std::set<AddressRange::Permission> flags;
+        std::set<AddressRange::Permission> permissions;
         if ((hdr.p_flags & PF_W) != 0)
-           flags.insert(AddressRange::Permission::write);
+           permissions.insert(AddressRange::Permission::write);
         if ((hdr.p_flags & PF_R) != 0)
-           flags.insert(AddressRange::Permission::read);
+           permissions.insert(AddressRange::Permission::read);
         if ((hdr.p_flags & PF_X) != 0)
-           flags.insert(AddressRange::Permission::exec);
+           permissions.insert(AddressRange::Permission::exec);
         rv.push_back( { hdr.p_vaddr, hdr.p_vaddr + hdr.p_memsz,
-                hdr.p_vaddr + hdr.p_filesz, 0, {0, 0, 0, name}, flags, {}});
+                hdr.p_vaddr + hdr.p_filesz, offset, {0, 0, inode, name}, permissions, {}});
     }
     return rv;
 }
@@ -284,11 +342,5 @@ CoreProcess::getSignalInfo() const {
    return std::nullopt;
 }
 
-std::ostream &operator << (std::ostream &os, const JSON<pstack::Procman::FileEntry> &j) {
-    return JObject(os)
-        .field("start", j.object.start)
-        .field("end", j.object.end)
-        .field("fileOff", j.object.fileOff);
-}
 }
 

libpstack/proc.h

@@ -427,54 +427,6 @@ struct FileNoteHeader {
     Elf::Off pageSize;
 };
 
-struct FileEntry {
-    Elf::Off start;
-    Elf::Off end;
-    Elf::Off fileOff;
-};
-
-class FileEntries {
-    FileNoteHeader header;
-    Reader::csptr entries;
-    std::unique_ptr<ReaderArray<FileEntry>> entriesArray;
-    Reader::csptr names;
-
-public:
-    class sentinel { };
-    class iterator {
-        friend class FileEntries;
-        const FileEntries &entries;
-        void fetch();
-        bool fetched = false;
-        size_t nameoff = 0;
-        std::pair<std::string, FileEntry> cur;
-        ReaderArray<FileEntry>::iterator entriesIterator;
-   public:
-        iterator(const FileEntries &entries, ReaderArray<FileEntry>::iterator start);
-        iterator &operator++();
-        std::pair<std::string, FileEntry> operator *() { fetch(); return cur; }
-        bool operator != (const iterator &rhs) const { return entriesIterator != rhs.entriesIterator; }
-        bool operator != (const sentinel &) const { return entriesIterator != entries.entriesArray->end(); }
-    };
-    FileEntries(const Elf::Object &obj) {
-        // find the Notes section.
-        for (auto note : obj.notes()) {
-            if (note.name() == "CORE" && note.type() == NT_FILE) {
-                auto data = note.data();
-                header = data->readObj<FileNoteHeader>(0);
-                entries = data->view("FILE note entries", sizeof header, header.count * sizeof (FileEntry));
-                names = data->view("FILE note names", sizeof header + header.count * sizeof (FileEntry));
-                break;
-            }
-        }
-        if (!entries)
-           entries = std::make_shared<NullReader>();
-        entriesArray = std::make_unique<ReaderArray<FileEntry>>(*entries);
-    }
-    iterator begin() const { return iterator(*this, entriesArray->begin()); }
-    sentinel end() const { return sentinel{}; }
-};
-
 
 struct WaitStatus {
     int status;
@@ -493,7 +445,6 @@ std::ostream &operator << (std::ostream &os, WaitStatus ws);
 
 std::ostream &operator << (std::ostream &os, const JSON<pstack::Procman::StackFrame, pstack::Procman::Process *> &jt);
 std::ostream &operator << (std::ostream &os, const JSON<pstack::Procman::ThreadStack, pstack::Procman::Process *> &jt);
-std::ostream &operator << (std::ostream &os, const JSON<pstack::Procman::FileEntry> &);
 
 }