1 //===-- CommandHistory.cpp ------------------------------------------------===//
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 #include <cinttypes>
10 
11 #include "lldb/Interpreter/CommandHistory.h"
12 
13 using namespace lldb;
14 using namespace lldb_private;
15 
16 size_t CommandHistory::GetSize() const {
17   std::lock_guard<std::recursive_mutex> guard(m_mutex);
18   return m_history.size();
19 }
20 
21 bool CommandHistory::IsEmpty() const {
22   std::lock_guard<std::recursive_mutex> guard(m_mutex);
23   return m_history.empty();
24 }
25 
26 llvm::Optional<llvm::StringRef>
27 CommandHistory::FindString(llvm::StringRef input_str) const {
28   std::lock_guard<std::recursive_mutex> guard(m_mutex);
29   if (input_str.size() < 2)
30     return llvm::None;
31 
32   if (input_str[0] != g_repeat_char)
33     return llvm::None;
34 
35   if (input_str[1] == g_repeat_char) {
36     if (m_history.empty())
37       return llvm::None;
38     return llvm::StringRef(m_history.back());
39   }
40 
41   input_str = input_str.drop_front();
42 
43   size_t idx = 0;
44   if (input_str.front() == '-') {
45     if (input_str.drop_front(1).getAsInteger(0, idx))
46       return llvm::None;
47     if (idx >= m_history.size())
48       return llvm::None;
49     idx = m_history.size() - idx;
50   } else {
51     if (input_str.getAsInteger(0, idx))
52       return llvm::None;
53     if (idx >= m_history.size())
54       return llvm::None;
55   }
56 
57   return llvm::StringRef(m_history[idx]);
58 }
59 
60 llvm::StringRef CommandHistory::GetStringAtIndex(size_t idx) const {
61   std::lock_guard<std::recursive_mutex> guard(m_mutex);
62   if (idx < m_history.size())
63     return m_history[idx];
64   return "";
65 }
66 
67 llvm::StringRef CommandHistory::operator[](size_t idx) const {
68   return GetStringAtIndex(idx);
69 }
70 
71 llvm::StringRef CommandHistory::GetRecentmostString() const {
72   std::lock_guard<std::recursive_mutex> guard(m_mutex);
73   if (m_history.empty())
74     return "";
75   return m_history.back();
76 }
77 
78 void CommandHistory::AppendString(llvm::StringRef str, bool reject_if_dupe) {
79   std::lock_guard<std::recursive_mutex> guard(m_mutex);
80   if (reject_if_dupe) {
81     if (!m_history.empty()) {
82       if (str == m_history.back())
83         return;
84     }
85   }
86   m_history.push_back(std::string(str));
87 }
88 
89 void CommandHistory::Clear() {
90   std::lock_guard<std::recursive_mutex> guard(m_mutex);
91   m_history.clear();
92 }
93 
94 void CommandHistory::Dump(Stream &stream, size_t start_idx,
95                           size_t stop_idx) const {
96   std::lock_guard<std::recursive_mutex> guard(m_mutex);
97   stop_idx = std::min(stop_idx + 1, m_history.size());
98   for (size_t counter = start_idx; counter < stop_idx; counter++) {
99     const std::string hist_item = m_history[counter];
100     if (!hist_item.empty()) {
101       stream.Indent();
102       stream.Printf("%4" PRIu64 ": %s\n", (uint64_t)counter, hist_item.c_str());
103     }
104   }
105 }
106