1 //===-- DNBBreakpoint.h -----------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  Created by Greg Clayton on 6/29/07.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLDB_TOOLS_DEBUGSERVER_SOURCE_DNBBREAKPOINT_H
14 #define LLDB_TOOLS_DEBUGSERVER_SOURCE_DNBBREAKPOINT_H
15 
16 #include <mach/mach.h>
17 
18 #include <map>
19 #include <vector>
20 
21 #include "DNBDefs.h"
22 
23 class MachProcess;
24 
25 class DNBBreakpoint {
26 public:
27   DNBBreakpoint(nub_addr_t m_addr, nub_size_t byte_size, bool hardware);
28   ~DNBBreakpoint();
29 
ByteSize()30   nub_size_t ByteSize() const { return m_byte_size; }
SavedOpcodeBytes()31   uint8_t *SavedOpcodeBytes() { return &m_opcode[0]; }
SavedOpcodeBytes()32   const uint8_t *SavedOpcodeBytes() const { return &m_opcode[0]; }
Address()33   nub_addr_t Address() const { return m_addr; }
34   //    nub_thread_t ThreadID() const { return m_tid; }
IsEnabled()35   bool IsEnabled() const { return m_enabled; }
IntersectsRange(nub_addr_t addr,nub_size_t size,nub_addr_t * intersect_addr,nub_size_t * intersect_size,nub_size_t * opcode_offset)36   bool IntersectsRange(nub_addr_t addr, nub_size_t size,
37                        nub_addr_t *intersect_addr, nub_size_t *intersect_size,
38                        nub_size_t *opcode_offset) const {
39     // We only use software traps for software breakpoints
40     if (IsBreakpoint() && IsEnabled() && !IsHardware()) {
41       if (m_byte_size > 0) {
42         const nub_addr_t bp_end_addr = m_addr + m_byte_size;
43         const nub_addr_t end_addr = addr + size;
44         // Is the breakpoint end address before the passed in start address?
45         if (bp_end_addr <= addr)
46           return false;
47         // Is the breakpoint start address after passed in end address?
48         if (end_addr <= m_addr)
49           return false;
50         if (intersect_addr || intersect_size || opcode_offset) {
51           if (m_addr < addr) {
52             if (intersect_addr)
53               *intersect_addr = addr;
54             if (intersect_size)
55               *intersect_size =
56                   std::min<nub_addr_t>(bp_end_addr, end_addr) - addr;
57             if (opcode_offset)
58               *opcode_offset = addr - m_addr;
59           } else {
60             if (intersect_addr)
61               *intersect_addr = m_addr;
62             if (intersect_size)
63               *intersect_size =
64                   std::min<nub_addr_t>(bp_end_addr, end_addr) - m_addr;
65             if (opcode_offset)
66               *opcode_offset = 0;
67           }
68         }
69         return true;
70       }
71     }
72     return false;
73   }
SetEnabled(bool enabled)74   void SetEnabled(bool enabled) {
75     if (!enabled)
76       SetHardwareIndex(INVALID_NUB_HW_INDEX);
77     m_enabled = enabled;
78   }
SetIsWatchpoint(uint32_t type)79   void SetIsWatchpoint(uint32_t type) {
80     m_is_watchpoint = 1;
81     m_watch_read = (type & WATCH_TYPE_READ) != 0;
82     m_watch_write = (type & WATCH_TYPE_WRITE) != 0;
83   }
IsBreakpoint()84   bool IsBreakpoint() const { return m_is_watchpoint == 0; }
IsWatchpoint()85   bool IsWatchpoint() const { return m_is_watchpoint == 1; }
WatchpointRead()86   bool WatchpointRead() const { return m_watch_read != 0; }
WatchpointWrite()87   bool WatchpointWrite() const { return m_watch_write != 0; }
HardwarePreferred()88   bool HardwarePreferred() const { return m_hw_preferred; }
IsHardware()89   bool IsHardware() const { return m_hw_index != INVALID_NUB_HW_INDEX; }
GetHardwareIndex()90   uint32_t GetHardwareIndex() const { return m_hw_index; }
SetHardwareIndex(uint32_t hw_index)91   void SetHardwareIndex(uint32_t hw_index) { m_hw_index = hw_index; }
92   void Dump() const;
Retain()93   uint32_t Retain() { return ++m_retain_count; }
Release()94   uint32_t Release() {
95     if (m_retain_count == 0)
96       return 0;
97     return --m_retain_count;
98   }
99 
100 private:
101   uint32_t m_retain_count; // Each breakpoint is maintained by address and is
102                            // ref counted in case multiple people set a
103                            // breakpoint at the same address
104   uint32_t m_byte_size;    // Length in bytes of the breakpoint if set in memory
105   uint8_t m_opcode[8];     // Saved opcode bytes
106   nub_addr_t m_addr;       // Address of this breakpoint
107   uint32_t m_enabled : 1,  // Flags for this breakpoint
108       m_hw_preferred : 1,  // 1 if this point has been requested to be set using
109                            // hardware (which may fail due to lack of resources)
110       m_is_watchpoint : 1, // 1 if this is a watchpoint
111       m_watch_read : 1,    // 1 if we stop when the watched data is read from
112       m_watch_write : 1;   // 1 if we stop when the watched data is written to
113   uint32_t
114       m_hw_index; // The hardware resource index for this breakpoint/watchpoint
115 };
116 
117 class DNBBreakpointList {
118 public:
119   DNBBreakpointList();
120   ~DNBBreakpointList();
121 
122   DNBBreakpoint *Add(nub_addr_t addr, nub_size_t length, bool hardware);
123   bool Remove(nub_addr_t addr);
124   DNBBreakpoint *FindByAddress(nub_addr_t addr);
125   const DNBBreakpoint *FindByAddress(nub_addr_t addr) const;
126 
127   size_t FindBreakpointsThatOverlapRange(nub_addr_t addr, nub_addr_t size,
128                                          std::vector<DNBBreakpoint *> &bps);
129 
130   void Dump() const;
131 
Size()132   size_t Size() const { return m_breakpoints.size(); }
133   void DisableAll();
134 
135   void RemoveTrapsFromBuffer(nub_addr_t addr, nub_size_t size, void *buf) const;
136 
137   void DisableAllBreakpoints(MachProcess *process);
138   void DisableAllWatchpoints(MachProcess *process);
139   void RemoveDisabled();
140 
141 protected:
142   typedef std::map<nub_addr_t, DNBBreakpoint> collection;
143   typedef collection::iterator iterator;
144   typedef collection::const_iterator const_iterator;
145   collection m_breakpoints;
146 };
147 
148 #endif
149