1 files changed, 205 insertions, 0 deletions
diff --git a/contrib/llvm-project/lldb/source/Plugins/Process/Utility/LinuxProcMaps.cpp b/contrib/llvm-project/lldb/source/Plugins/Process/Utility/LinuxProcMaps.cpp
new file mode 100644
index 000000000000..fd803c8cabaf
--- /dev/null
+++ b/contrib/llvm-project/lldb/source/Plugins/Process/Utility/LinuxProcMaps.cpp
@@ -0,0 +1,205 @@
+//===-- LinuxProcMaps.cpp -------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "LinuxProcMaps.h"
+#include "lldb/Target/MemoryRegionInfo.h"
+#include "lldb/Utility/Status.h"
+#include "lldb/Utility/StringExtractor.h"
+#include "llvm/ADT/StringRef.h"
+#include <optional>
+
+using namespace lldb_private;
+
+enum class MapsKind { Maps, SMaps };
+
+static llvm::Expected<MemoryRegionInfo> ProcMapError(const char *msg,
+                                                     MapsKind kind) {
+  return llvm::createStringError(llvm::inconvertibleErrorCode(), msg,
+                                 kind == MapsKind::Maps ? "maps" : "smaps");
+}
+
+static llvm::Expected<MemoryRegionInfo>
+ParseMemoryRegionInfoFromProcMapsLine(llvm::StringRef maps_line,
+                                      MapsKind maps_kind) {
+  MemoryRegionInfo region;
+  StringExtractor line_extractor(maps_line);
+
+  // Format: {address_start_hex}-{address_end_hex} perms offset  dev   inode
+  // pathname perms: rwxp   (letter is present if set, '-' if not, final
+  // character is p=private, s=shared).
+
+  // Parse out the starting address
+  lldb::addr_t start_address = line_extractor.GetHexMaxU64(false, 0);
+
+  // Parse out hyphen separating start and end address from range.
+  if (!line_extractor.GetBytesLeft() || (line_extractor.GetChar() != '-'))
+    return ProcMapError(
+        "malformed /proc/{pid}/%s entry, missing dash between address range",
+        maps_kind);
+
+  // Parse out the ending address
+  lldb::addr_t end_address = line_extractor.GetHexMaxU64(false, start_address);
+
+  // Parse out the space after the address.
+  if (!line_extractor.GetBytesLeft() || (line_extractor.GetChar() != ' '))
+    return ProcMapError(
+        "malformed /proc/{pid}/%s entry, missing space after range", maps_kind);
+
+  // Save the range.
+  region.GetRange().SetRangeBase(start_address);
+  region.GetRange().SetRangeEnd(end_address);
+
+  // Any memory region in /proc/{pid}/(maps|smaps) is by definition mapped
+  // into the process.
+  region.SetMapped(MemoryRegionInfo::OptionalBool::eYes);
+
+  // Parse out each permission entry.
+  if (line_extractor.GetBytesLeft() < 4)
+    return ProcMapError(
+        "malformed /proc/{pid}/%s entry, missing some portion of "
+        "permissions",
+        maps_kind);
+
+  // Handle read permission.
+  const char read_perm_char = line_extractor.GetChar();
+  if (read_perm_char == 'r')
+    region.SetReadable(MemoryRegionInfo::OptionalBool::eYes);
+  else if (read_perm_char == '-')
+    region.SetReadable(MemoryRegionInfo::OptionalBool::eNo);
+  else
+    return ProcMapError("unexpected /proc/{pid}/%s read permission char",
+                        maps_kind);
+
+  // Handle write permission.
+  const char write_perm_char = line_extractor.GetChar();
+  if (write_perm_char == 'w')
+    region.SetWritable(MemoryRegionInfo::OptionalBool::eYes);
+  else if (write_perm_char == '-')
+    region.SetWritable(MemoryRegionInfo::OptionalBool::eNo);
+  else
+    return ProcMapError("unexpected /proc/{pid}/%s write permission char",
+                        maps_kind);
+
+  // Handle execute permission.
+  const char exec_perm_char = line_extractor.GetChar();
+  if (exec_perm_char == 'x')
+    region.SetExecutable(MemoryRegionInfo::OptionalBool::eYes);
+  else if (exec_perm_char == '-')
+    region.SetExecutable(MemoryRegionInfo::OptionalBool::eNo);
+  else
+    return ProcMapError("unexpected /proc/{pid}/%s exec permission char",
+                        maps_kind);
+
+  // Handle sharing status (private/shared).
+  const char sharing_char = line_extractor.GetChar();
+  if (sharing_char == 's')
+    region.SetShared(MemoryRegionInfo::OptionalBool::eYes);
+  else if (sharing_char == 'p')
+    region.SetShared(MemoryRegionInfo::OptionalBool::eNo);
+  else
+    region.SetShared(MemoryRegionInfo::OptionalBool::eDontKnow);
+
+  line_extractor.SkipSpaces();           // Skip the separator
+  line_extractor.GetHexMaxU64(false, 0); // Read the offset
+  line_extractor.GetHexMaxU64(false, 0); // Read the major device number
+  line_extractor.GetChar();              // Read the device id separator
+  line_extractor.GetHexMaxU64(false, 0); // Read the major device number
+  line_extractor.SkipSpaces();           // Skip the separator
+  line_extractor.GetU64(0, 10);          // Read the inode number
+
+  line_extractor.SkipSpaces();
+  const char *name = line_extractor.Peek();
+  if (name)
+    region.SetName(name);
+
+  return region;
+}
+
+void lldb_private::ParseLinuxMapRegions(llvm::StringRef linux_map,
+                                        LinuxMapCallback const &callback) {
+  llvm::StringRef lines(linux_map);
+  llvm::StringRef line;
+  while (!lines.empty()) {
+    std::tie(line, lines) = lines.split('\n');
+    if (!callback(ParseMemoryRegionInfoFromProcMapsLine(line, MapsKind::Maps)))
+      break;
+  }
+}
+
+void lldb_private::ParseLinuxSMapRegions(llvm::StringRef linux_smap,
+                                         LinuxMapCallback const &callback) {
+  // Entries in /smaps look like:
+  // 00400000-0048a000 r-xp 00000000 fd:03 960637
+  // Size:                552 kB
+  // Rss:                 460 kB
+  // <...>
+  // VmFlags: rd ex mr mw me dw
+  // 00500000-0058a000 rwxp 00000000 fd:03 960637
+  // <...>
+  //
+  // Where the first line is identical to the /maps format
+  // and VmFlags is only printed for kernels >= 3.8.
+
+  llvm::StringRef lines(linux_smap);
+  llvm::StringRef line;
+  std::optional<MemoryRegionInfo> region;
+
+  while (lines.size()) {
+    std::tie(line, lines) = lines.split('\n');
+
+    // A property line looks like:
+    // <word>: <value>
+    // (no spaces on the left hand side)
+    // A header will have a ':' but the LHS will contain spaces
+    llvm::StringRef name;
+    llvm::StringRef value;
+    std::tie(name, value) = line.split(':');
+
+    // If this line is a property line
+    if (!name.contains(' ')) {
+      if (region) {
+        if (name == "VmFlags") {
+          if (value.contains("mt"))
+            region->SetMemoryTagged(MemoryRegionInfo::eYes);
+          else
+            region->SetMemoryTagged(MemoryRegionInfo::eNo);
+        }
+        // Ignore anything else
+      } else {
+        // Orphaned settings line
+        callback(ProcMapError(
+            "Found a property line without a corresponding mapping "
+            "in /proc/{pid}/%s",
+            MapsKind::SMaps));
+        return;
+      }
+    } else {
+      // Must be a new region header
+      if (region) {
+        // Save current region
+        callback(*region);
+        region.reset();
+      }
+
+      // Try to start a new region
+      llvm::Expected<MemoryRegionInfo> new_region =
+          ParseMemoryRegionInfoFromProcMapsLine(line, MapsKind::SMaps);
+      if (new_region) {
+        region = *new_region;
+      } else {
+        // Stop at first invalid region header
+        callback(new_region.takeError());
+        return;
+      }
+    }
+  }
+
+  // Catch last region
+  if (region)
+    callback(*region);
+}