contrib/llvm/tools/lldb/source/Plugins/Process/Utility/LinuxProcMaps.cpp

   1 //===-- LinuxProcMaps.cpp ---------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #include "LinuxProcMaps.h"
  11 #include "llvm/ADT/StringRef.h"
  12 #include "lldb/Target/MemoryRegionInfo.h"
  13 #include "lldb/Utility/Status.h"
  14 #include "lldb/Utility/StringExtractor.h"
  15
  16 using namespace lldb_private;
  17
  18 static Status
  19 ParseMemoryRegionInfoFromProcMapsLine(llvm::StringRef maps_line,
  20                                       MemoryRegionInfo &memory_region_info) {
  21   memory_region_info.Clear();
  22
  23   StringExtractor line_extractor(maps_line);
  24
  25   // Format: {address_start_hex}-{address_end_hex} perms offset  dev   inode
  26   // pathname perms: rwxp   (letter is present if set, '-' if not, final
  27   // character is p=private, s=shared).
  28
  29   // Parse out the starting address
  30   lldb::addr_t start_address = line_extractor.GetHexMaxU64(false, 0);
  31
  32   // Parse out hyphen separating start and end address from range.
  33   if (!line_extractor.GetBytesLeft() || (line_extractor.GetChar() != '-'))
  34     return Status(
  35         "malformed /proc/{pid}/maps entry, missing dash between address range");
  36
  37   // Parse out the ending address
  38   lldb::addr_t end_address = line_extractor.GetHexMaxU64(false, start_address);
  39
  40   // Parse out the space after the address.
  41   if (!line_extractor.GetBytesLeft() || (line_extractor.GetChar() != ' '))
  42     return Status(
  43         "malformed /proc/{pid}/maps entry, missing space after range");
  44
  45   // Save the range.
  46   memory_region_info.GetRange().SetRangeBase(start_address);
  47   memory_region_info.GetRange().SetRangeEnd(end_address);
  48
  49   // Any memory region in /proc/{pid}/maps is by definition mapped into the
  50   // process.
  51   memory_region_info.SetMapped(MemoryRegionInfo::OptionalBool::eYes);
  52
  53   // Parse out each permission entry.
  54   if (line_extractor.GetBytesLeft() < 4)
  55     return Status("malformed /proc/{pid}/maps entry, missing some portion of "
  56                   "permissions");
  57
  58   // Handle read permission.
  59   const char read_perm_char = line_extractor.GetChar();
  60   if (read_perm_char == 'r')
  61     memory_region_info.SetReadable(MemoryRegionInfo::OptionalBool::eYes);
  62   else if (read_perm_char == '-')
  63     memory_region_info.SetReadable(MemoryRegionInfo::OptionalBool::eNo);
  64   else
  65     return Status("unexpected /proc/{pid}/maps read permission char");
  66
  67   // Handle write permission.
  68   const char write_perm_char = line_extractor.GetChar();
  69   if (write_perm_char == 'w')
  70     memory_region_info.SetWritable(MemoryRegionInfo::OptionalBool::eYes);
  71   else if (write_perm_char == '-')
  72     memory_region_info.SetWritable(MemoryRegionInfo::OptionalBool::eNo);
  73   else
  74     return Status("unexpected /proc/{pid}/maps write permission char");
  75
  76   // Handle execute permission.
  77   const char exec_perm_char = line_extractor.GetChar();
  78   if (exec_perm_char == 'x')
  79     memory_region_info.SetExecutable(MemoryRegionInfo::OptionalBool::eYes);
  80   else if (exec_perm_char == '-')
  81     memory_region_info.SetExecutable(MemoryRegionInfo::OptionalBool::eNo);
  82   else
  83     return Status("unexpected /proc/{pid}/maps exec permission char");
  84
  85   line_extractor.GetChar();              // Read the private bit
  86   line_extractor.SkipSpaces();           // Skip the separator
  87   line_extractor.GetHexMaxU64(false, 0); // Read the offset
  88   line_extractor.GetHexMaxU64(false, 0); // Read the major device number
  89   line_extractor.GetChar();              // Read the device id separator
  90   line_extractor.GetHexMaxU64(false, 0); // Read the major device number
  91   line_extractor.SkipSpaces();           // Skip the separator
  92   line_extractor.GetU64(0, 10);          // Read the inode number
  93
  94   line_extractor.SkipSpaces();
  95   const char *name = line_extractor.Peek();
  96   if (name)
  97     memory_region_info.SetName(name);
  98
  99   return Status();
 100 }
 101
 102 void lldb_private::ParseLinuxMapRegions(llvm::StringRef linux_map,
 103                                         LinuxMapCallback const &callback) {
 104   llvm::StringRef lines(linux_map);
 105   llvm::StringRef line;
 106   while (!lines.empty()) {
 107     std::tie(line, lines) = lines.split('\n');
 108     MemoryRegionInfo region;
 109     Status error = ParseMemoryRegionInfoFromProcMapsLine(line, region);
 110     if (!callback(region, error))
 111       break;
 112   }
 113 }