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
|
#include "current-process.hh"
#include "error.hh"
#include "file-system.hh"
#include "logging.hh"
#include "namespaces.hh"
#include "signals.hh"
#include "strings.hh"
#include <math.h>
#ifdef __APPLE__
# include <mach-o/dyld.h>
#endif
#if __linux__
# include <sys/resource.h>
#endif
#if __FreeBSD__
# include <sys/param.h>
# include <sys/sysctl.h>
#endif
#include <sys/mount.h>
#include <cgroup.hh>
namespace nix {
unsigned int getMaxCPU()
{
#if __linux__
try {
auto cgroupFS = getCgroupFS();
if (!cgroupFS) return 0;
auto cgroups = getCgroups("/proc/self/cgroup");
auto cgroup = cgroups[""];
if (cgroup == "") return 0;
auto cpuFile = *cgroupFS + "/" + cgroup + "/cpu.max";
auto cpuMax = readFile(cpuFile);
auto cpuMaxParts = tokenizeString<std::vector<std::string>>(cpuMax, " \n");
if (cpuMaxParts.size() != 2) {
return 0;
}
auto quota = cpuMaxParts[0];
auto period = cpuMaxParts[1];
if (quota != "max")
return std::ceil(std::stoi(quota) / std::stof(period));
} catch (Error &) { ignoreException(lvlDebug); }
#endif
return 0;
}
rlim_t savedStackSize = 0;
void setStackSize(rlim_t stackSize)
{
struct rlimit limit;
if (getrlimit(RLIMIT_STACK, &limit) == 0 && limit.rlim_cur < stackSize) {
savedStackSize = limit.rlim_cur;
limit.rlim_cur = std::min(stackSize, limit.rlim_max);
if (setrlimit(RLIMIT_STACK, &limit) != 0) {
logger->log(
lvlError,
HintFmt(
"Failed to increase stack size from %1% to %2% (maximum allowed stack size: %3%): %4%",
savedStackSize,
stackSize,
limit.rlim_max,
std::strerror(errno)
).str()
);
}
}
}
void restoreProcessContext(bool restoreMounts)
{
restoreSignals();
if (restoreMounts) {
restoreMountNamespace();
}
if (savedStackSize) {
struct rlimit limit;
if (getrlimit(RLIMIT_STACK, &limit) == 0) {
limit.rlim_cur = savedStackSize;
setrlimit(RLIMIT_STACK, &limit);
}
}
}
std::optional<Path> getSelfExe()
{
static auto cached = []() -> std::optional<Path>
{
#if __linux__
return readLink("/proc/self/exe");
#elif __APPLE__
char buf[1024];
uint32_t size = sizeof(buf);
if (_NSGetExecutablePath(buf, &size) == 0)
return buf;
else
return std::nullopt;
#elif __FreeBSD__
int sysctlName[] = {
CTL_KERN,
KERN_PROC,
KERN_PROC_PATHNAME,
-1,
};
size_t pathLen = 0;
if (sysctl(sysctlName, sizeof(sysctlName) / sizeof(sysctlName[0]), nullptr, &pathLen, nullptr, 0) < 0) {
return std::nullopt;
}
std::vector<char> path(pathLen);
if (sysctl(sysctlName, sizeof(sysctlName) / sizeof(sysctlName[0]), path.data(), &pathLen, nullptr, 0) < 0) {
return std::nullopt;
}
return Path(path.begin(), path.end());
#else
return std::nullopt;
#endif
}();
return cached;
}
}
|
