1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
#include <iostream>
#include <unistd.h>
#include "test-session.hh"
#include "util.hh"
#include "escape-char.hh"
namespace nix {
static constexpr const bool DEBUG_REPL_PARSER = false;
RunningProcess RunningProcess::start(std::string executable, Strings args)
{
args.push_front(executable);
Pipe procStdin{};
Pipe procStdout{};
procStdin.create();
procStdout.create();
// This is separate from runProgram2 because we have different IO requirements
pid_t pid = startProcess([&]() {
if (dup2(procStdout.writeSide.get(), STDOUT_FILENO) == -1)
throw SysError("dupping stdout");
if (dup2(procStdin.readSide.get(), STDIN_FILENO) == -1)
throw SysError("dupping stdin");
procStdin.writeSide.close();
procStdout.readSide.close();
if (dup2(STDOUT_FILENO, STDERR_FILENO) == -1)
throw SysError("dupping stderr");
execv(executable.c_str(), stringsToCharPtrs(args).data());
throw SysError("exec did not happen");
});
procStdout.writeSide.close();
procStdin.readSide.close();
return RunningProcess{
.pid = pid,
.procStdin = std::move(procStdin),
.procStdout = std::move(procStdout),
};
}
[[gnu::unused]]
std::ostream & operator<<(std::ostream & os, ReplOutputParser::State s)
{
switch (s) {
case ReplOutputParser::State::Prompt:
os << "prompt";
break;
case ReplOutputParser::State::Context:
os << "context";
break;
}
return os;
}
void ReplOutputParser::transition(State new_state, char responsible_char, bool wasPrompt)
{
if constexpr (DEBUG_REPL_PARSER) {
std::cerr << "transition " << new_state << " for " << MaybeHexEscapedChar{responsible_char}
<< (wasPrompt ? " [prompt]" : "") << "\n";
}
state = new_state;
pos_in_prompt = 0;
}
bool ReplOutputParser::feed(char c)
{
if (c == '\n') {
transition(State::Prompt, c);
return false;
}
switch (state) {
case State::Context:
break;
case State::Prompt:
if (pos_in_prompt == prompt.length() - 1 && prompt[pos_in_prompt] == c) {
transition(State::Context, c, true);
return true;
}
if (pos_in_prompt >= prompt.length() - 1 || prompt[pos_in_prompt] != c) {
transition(State::Context, c);
break;
}
pos_in_prompt++;
break;
}
return false;
}
/** Waits for the prompt and then returns if a prompt was found */
bool TestSession::waitForPrompt()
{
std::vector<char> buf(1024);
for (;;) {
ssize_t res = read(proc.procStdout.readSide.get(), buf.data(), buf.size());
if (res < 0) {
throw SysError("read");
}
if (res == 0) {
return false;
}
bool foundPrompt = false;
for (ssize_t i = 0; i < res; ++i) {
// foundPrompt = foundPrompt || outputParser.feed(buf[i]);
bool wasEaten = true;
eater.feed(buf[i], [&](char c) {
wasEaten = false;
foundPrompt = outputParser.feed(buf[i]) || foundPrompt;
outLog.push_back(c);
});
if constexpr (DEBUG_REPL_PARSER) {
std::cerr << "raw " << MaybeHexEscapedChar{buf[i]} << (wasEaten ? " [eaten]" : "") << "\n";
}
}
if (foundPrompt) {
return true;
}
}
}
void TestSession::close()
{
proc.procStdin.close();
proc.procStdout.close();
}
void TestSession::runCommand(std::string command)
{
if constexpr (DEBUG_REPL_PARSER)
std::cerr << "runCommand " << command << "\n";
command += "\n";
// We have to feed a newline into the output parser, since Nix might not
// give us a newline before a prompt in all cases (it might clear line
// first, e.g.)
outputParser.feed('\n');
// Echo is disabled, so we have to make our own
outLog.append(command);
writeFull(proc.procStdin.writeSide.get(), command, false);
}
};
|