htop/linux/CGroupUtils.c

318 lines
8.3 KiB
C

/*
htop - CGroupUtils.h
(C) 2021 htop dev team
Released under the GNU GPLv2+, see the COPYING file
in the source distribution for its full text.
*/
#include "linux/CGroupUtils.h"
#include "XUtils.h"
typedef struct StrBuf_state {
char *buf;
size_t size;
size_t pos;
} StrBuf_state;
typedef bool (*StrBuf_putc_t)(StrBuf_state* p, char c);
static bool StrBuf_putc_count(StrBuf_state* p, ATTR_UNUSED char c) {
p->pos++;
return true;
}
static bool StrBuf_putc_write(StrBuf_state* p, char c) {
if (p->pos >= p->size)
return false;
p->buf[p->pos] = c;
p->pos++;
return true;
}
static bool StrBuf_putsn(StrBuf_state* p, StrBuf_putc_t w, const char* s, size_t count) {
for (; count; count--)
if (!w(p, *s++))
return false;
return true;
}
static bool StrBuf_putsz(StrBuf_state* p, StrBuf_putc_t w, const char* s) {
while (*s)
if (!w(p, *s++))
return false;
return true;
}
static bool Label_checkEqual(const char* labelStart, size_t labelLen, const char* expected) {
return labelLen == strlen(expected) && String_startsWith(labelStart, expected);
}
static bool Label_checkPrefix(const char* labelStart, size_t labelLen, const char* expected) {
return labelLen > strlen(expected) && String_startsWith(labelStart, expected);
}
static bool Label_checkSuffix(const char* labelStart, size_t labelLen, const char* expected) {
return labelLen > strlen(expected) && String_startsWith(labelStart + labelLen - strlen(expected), expected);
}
static bool CGroup_filterName_internal(const char *cgroup, StrBuf_state* s, StrBuf_putc_t w) {
const char* str_slice_suffix = ".slice";
const char* str_system_slice = "system.slice";
const char* str_user_slice = "user.slice";
const char* str_machine_slice = "machine.slice";
const char* str_user_slice_prefix = "/user-";
const char* str_lxc_monitor_legacy = "lxc.monitor";
const char* str_lxc_payload_legacy = "lxc.payload";
const char* str_lxc_monitor_prefix = "lxc.monitor.";
const char* str_lxc_payload_prefix = "lxc.payload.";
const char* str_nspawn_scope_prefix = "machine-";
const char* str_nspawn_monitor_label = "/supervisor";
const char* str_nspawn_payload_label = "/payload";
const char* str_service_suffix = ".service";
const char* str_scope_suffix = ".scope";
while (*cgroup) {
if ('/' == *cgroup) {
while ('/' == *cgroup)
cgroup++;
if (!w(s, '/'))
return false;
continue;
}
const char* labelStart = cgroup;
const char* nextSlash = strchrnul(labelStart, '/');
const size_t labelLen = nextSlash - labelStart;
if (Label_checkEqual(labelStart, labelLen, str_system_slice)) {
cgroup = nextSlash;
if (!StrBuf_putsz(s, w, "[S]"))
return false;
continue;
}
if (Label_checkEqual(labelStart, labelLen, str_machine_slice)) {
cgroup = nextSlash;
if (!StrBuf_putsz(s, w, "[M]"))
return false;
continue;
}
if (Label_checkEqual(labelStart, labelLen, str_user_slice)) {
cgroup = nextSlash;
if (!StrBuf_putsz(s, w, "[U]"))
return false;
if (!String_startsWith(cgroup, str_user_slice_prefix))
continue;
const char* userSliceSlash = strchrnul(cgroup + strlen(str_user_slice_prefix), '/');
const char* sliceSpec = userSliceSlash - strlen(str_slice_suffix);
if (!String_startsWith(sliceSpec, str_slice_suffix))
continue;
const size_t sliceNameLen = sliceSpec - (cgroup + strlen(str_user_slice_prefix));
s->pos--;
if (!w(s, ':'))
return false;
if (!StrBuf_putsn(s, w, cgroup + strlen(str_user_slice_prefix), sliceNameLen))
return false;
if (!w(s, ']'))
return false;
cgroup = userSliceSlash;
continue;
}
if (Label_checkSuffix(labelStart, labelLen, str_slice_suffix)) {
const size_t sliceNameLen = labelLen - strlen(str_slice_suffix);
if (!w(s, '['))
return false;
if (!StrBuf_putsn(s, w, cgroup, sliceNameLen))
return false;
if (!w(s, ']'))
return false;
cgroup = nextSlash;
continue;
}
if (Label_checkPrefix(labelStart, labelLen, str_lxc_payload_prefix)) {
const size_t cgroupNameLen = labelLen - strlen(str_lxc_payload_prefix);
if (!StrBuf_putsz(s, w, "[lxc:"))
return false;
if (!StrBuf_putsn(s, w, cgroup + strlen(str_lxc_payload_prefix), cgroupNameLen))
return false;
if (!w(s, ']'))
return false;
cgroup = nextSlash;
continue;
}
if (Label_checkPrefix(labelStart, labelLen, str_lxc_monitor_prefix)) {
const size_t cgroupNameLen = labelLen - strlen(str_lxc_monitor_prefix);
if (!StrBuf_putsz(s, w, "[LXC:"))
return false;
if (!StrBuf_putsn(s, w, cgroup + strlen(str_lxc_monitor_prefix), cgroupNameLen))
return false;
if (!w(s, ']'))
return false;
cgroup = nextSlash;
continue;
}
// LXC legacy cgroup naming
if (Label_checkEqual(labelStart, labelLen, str_lxc_monitor_legacy) ||
Label_checkEqual(labelStart, labelLen, str_lxc_payload_legacy)) {
bool isMonitor = Label_checkEqual(labelStart, labelLen, str_lxc_monitor_legacy);
labelStart = nextSlash;
while (*labelStart == '/')
labelStart++;
nextSlash = strchrnul(labelStart, '/');
if (nextSlash - labelStart > 0) {
if (!StrBuf_putsz(s, w, isMonitor ? "[LXC:" : "[lxc:"))
return false;
if (!StrBuf_putsn(s, w, labelStart, nextSlash - labelStart))
return false;
if (!w(s, ']'))
return false;
cgroup = nextSlash;
continue;
}
labelStart = cgroup;
nextSlash = labelStart + labelLen;
}
if (Label_checkSuffix(labelStart, labelLen, str_service_suffix)) {
const size_t serviceNameLen = labelLen - strlen(str_service_suffix);
if (String_startsWith(cgroup, "user@")) {
cgroup = nextSlash;
while(*cgroup == '/')
cgroup++;
continue;
}
if (!StrBuf_putsn(s, w, cgroup, serviceNameLen))
return false;
cgroup = nextSlash;
continue;
}
if (Label_checkSuffix(labelStart, labelLen, str_scope_suffix)) {
const size_t scopeNameLen = labelLen - strlen(str_scope_suffix);
if (Label_checkPrefix(labelStart, scopeNameLen, str_nspawn_scope_prefix)) {
const size_t machineScopeNameLen = scopeNameLen - strlen(str_nspawn_scope_prefix);
const bool is_monitor = String_startsWith(nextSlash, str_nspawn_monitor_label);
if (!StrBuf_putsz(s, w, is_monitor ? "[SNC:" : "[snc:"))
return false;
if (!StrBuf_putsn(s, w, cgroup + strlen(str_nspawn_scope_prefix), machineScopeNameLen))
return false;
if (!w(s, ']'))
return false;
cgroup = nextSlash;
if (String_startsWith(nextSlash, str_nspawn_monitor_label))
cgroup += strlen(str_nspawn_monitor_label);
else if (String_startsWith(nextSlash, str_nspawn_payload_label))
cgroup += strlen(str_nspawn_payload_label);
continue;
}
if (!w(s, '!'))
return false;
if (!StrBuf_putsn(s, w, cgroup, scopeNameLen))
return false;
cgroup = nextSlash;
continue;
}
// Default behavior: Copy the full label
cgroup = labelStart;
if (!StrBuf_putsn(s, w, cgroup, labelLen))
return false;
cgroup = nextSlash;
}
return true;
}
char* CGroup_filterName(const char *cgroup) {
StrBuf_state s = {
.buf = NULL,
.size = 0,
.pos = 0,
};
if (!CGroup_filterName_internal(cgroup, &s, StrBuf_putc_count)) {
return NULL;
}
s.buf = xCalloc(s.pos + 1, sizeof(char));
s.size = s.pos;
s.pos = 0;
if (!CGroup_filterName_internal(cgroup, &s, StrBuf_putc_write)) {
free(s.buf);
return NULL;
}
s.buf[s.size] = '\0';
return s.buf;
}