virt: make virtualization enum a named type

These days we have a mechanism for safely returning errnos in enum
types, via definining -ERRNO_MAX as one special enu value. Let's use
that for Virtualization.

No change in behaviour, just some typesafety improvement.
This commit is contained in:
Lennart Poettering 2022-04-04 11:19:44 +02:00
parent 0f534758d1
commit 1b86c7c59e
8 changed files with 119 additions and 107 deletions

View File

@ -28,14 +28,14 @@ enum {
SMBIOS_VM_BIT_UNKNOWN,
};
static int detect_vm_cpuid(void) {
static Virtualization detect_vm_cpuid(void) {
/* CPUID is an x86 specific interface. */
#if defined(__i386__) || defined(__x86_64__)
static const struct {
const char sig[13];
int id;
Virtualization id;
} vm_table[] = {
{ "XenVMMXenVMM", VIRTUALIZATION_XEN },
{ "KVMKVMKVM", VIRTUALIZATION_KVM }, /* qemu with KVM */
@ -92,7 +92,7 @@ static int detect_vm_cpuid(void) {
return VIRTUALIZATION_NONE;
}
static int detect_vm_device_tree(void) {
static Virtualization detect_vm_device_tree(void) {
#if defined(__arm__) || defined(__aarch64__) || defined(__powerpc__) || defined(__powerpc64__)
_cleanup_free_ char *hvtype = NULL;
int r;
@ -142,7 +142,7 @@ static int detect_vm_device_tree(void) {
}
#if defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) || defined(__loongarch64)
static int detect_vm_dmi_vendor(void) {
static Virtualization detect_vm_dmi_vendor(void) {
static const char *const dmi_vendors[] = {
"/sys/class/dmi/id/product_name", /* Test this before sys_vendor to detect KVM over QEMU */
"/sys/class/dmi/id/sys_vendor",
@ -153,7 +153,7 @@ static int detect_vm_dmi_vendor(void) {
static const struct {
const char *vendor;
int id;
Virtualization id;
} dmi_vendor_table[] = {
{ "KVM", VIRTUALIZATION_KVM },
{ "Amazon EC2", VIRTUALIZATION_AMAZON },
@ -230,7 +230,7 @@ static int detect_vm_smbios(void) {
}
#endif /* defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) || defined(__loongarch64) */
static int detect_vm_dmi(void) {
static Virtualization detect_vm_dmi(void) {
#if defined(__i386__) || defined(__x86_64__) || defined(__arm__) || defined(__aarch64__) || defined(__loongarch64)
int r;
@ -332,7 +332,7 @@ static int detect_vm_xen_dom0(void) {
}
}
static int detect_vm_xen(void) {
static Virtualization detect_vm_xen(void) {
/* The presence of /proc/xen indicates some form of a Xen domain
The check for Dom0 is handled outside this function */
if (access("/proc/xen", F_OK) < 0) {
@ -343,7 +343,7 @@ static int detect_vm_xen(void) {
return VIRTUALIZATION_XEN;
}
static int detect_vm_hypervisor(void) {
static Virtualization detect_vm_hypervisor(void) {
_cleanup_free_ char *hvtype = NULL;
int r;
@ -361,7 +361,7 @@ static int detect_vm_hypervisor(void) {
return VIRTUALIZATION_VM_OTHER;
}
static int detect_vm_uml(void) {
static Virtualization detect_vm_uml(void) {
_cleanup_fclose_ FILE *f = NULL;
int r;
@ -400,7 +400,7 @@ static int detect_vm_uml(void) {
return VIRTUALIZATION_NONE;
}
static int detect_vm_zvm(void) {
static Virtualization detect_vm_zvm(void) {
#if defined(__s390__)
_cleanup_free_ char *t = NULL;
@ -424,10 +424,11 @@ static int detect_vm_zvm(void) {
}
/* Returns a short identifier for the various VM implementations */
int detect_vm(void) {
static thread_local int cached_found = _VIRTUALIZATION_INVALID;
Virtualization detect_vm(void) {
static thread_local Virtualization cached_found = _VIRTUALIZATION_INVALID;
bool other = false;
int r, dmi, xen_dom0 = 0;
int xen_dom0 = 0;
Virtualization v, dmi;
if (cached_found >= 0)
return cached_found;
@ -446,22 +447,22 @@ int detect_vm(void) {
dmi = detect_vm_dmi();
if (IN_SET(dmi, VIRTUALIZATION_ORACLE, VIRTUALIZATION_XEN, VIRTUALIZATION_AMAZON)) {
r = dmi;
v = dmi;
goto finish;
}
/* Detect UML */
r = detect_vm_uml();
if (r < 0)
return r;
if (r != VIRTUALIZATION_NONE)
v = detect_vm_uml();
if (v < 0)
return v;
if (v != VIRTUALIZATION_NONE)
goto finish;
/* Detect Xen */
r = detect_vm_xen();
if (r < 0)
return r;
if (r == VIRTUALIZATION_XEN) {
v = detect_vm_xen();
if (v < 0)
return v;
if (v == VIRTUALIZATION_XEN) {
/* If we are Dom0, then we expect to not report as a VM. However, as we might be nested
* inside another hypervisor which can be detected via the CPUID check, wait to report this
* until after the CPUID check. */
@ -471,17 +472,17 @@ int detect_vm(void) {
if (xen_dom0 == 0)
goto finish;
r = VIRTUALIZATION_NONE;
} else if (r != VIRTUALIZATION_NONE)
v = VIRTUALIZATION_NONE;
} else if (v != VIRTUALIZATION_NONE)
assert_not_reached();
/* Detect from CPUID */
r = detect_vm_cpuid();
if (r < 0)
return r;
if (r == VIRTUALIZATION_VM_OTHER)
v = detect_vm_cpuid();
if (v < 0)
return v;
if (v == VIRTUALIZATION_VM_OTHER)
other = true;
else if (r != VIRTUALIZATION_NONE)
else if (v != VIRTUALIZATION_NONE)
goto finish;
/* If we are in Dom0 and have not yet finished, finish with the result of detect_vm_cpuid */
@ -494,38 +495,38 @@ int detect_vm(void) {
if (dmi == VIRTUALIZATION_VM_OTHER)
other = true;
else if (dmi != VIRTUALIZATION_NONE) {
r = dmi;
v = dmi;
goto finish;
}
/* Check high-level hypervisor sysfs file */
r = detect_vm_hypervisor();
if (r < 0)
return r;
if (r == VIRTUALIZATION_VM_OTHER)
v = detect_vm_hypervisor();
if (v < 0)
return v;
if (v == VIRTUALIZATION_VM_OTHER)
other = true;
else if (r != VIRTUALIZATION_NONE)
else if (v != VIRTUALIZATION_NONE)
goto finish;
r = detect_vm_device_tree();
if (r < 0)
return r;
if (r == VIRTUALIZATION_VM_OTHER)
v = detect_vm_device_tree();
if (v < 0)
return v;
if (v == VIRTUALIZATION_VM_OTHER)
other = true;
else if (r != VIRTUALIZATION_NONE)
else if (v != VIRTUALIZATION_NONE)
goto finish;
r = detect_vm_zvm();
if (r < 0)
return r;
v = detect_vm_zvm();
if (v < 0)
return v;
finish:
if (r == VIRTUALIZATION_NONE && other)
r = VIRTUALIZATION_VM_OTHER;
if (v == VIRTUALIZATION_NONE && other)
v = VIRTUALIZATION_VM_OTHER;
cached_found = r;
log_debug("Found VM virtualization %s", virtualization_to_string(r));
return r;
cached_found = v;
log_debug("Found VM virtualization %s", virtualization_to_string(v));
return v;
}
static const char *const container_table[_VIRTUALIZATION_MAX] = {
@ -608,12 +609,12 @@ static int running_in_cgroupns(void) {
}
}
static int detect_container_files(void) {
static Virtualization detect_container_files(void) {
unsigned i;
static const struct {
const char *file_path;
int id;
Virtualization id;
} container_file_table[] = {
/* https://github.com/containers/podman/issues/6192 */
/* https://github.com/containers/podman/issues/3586#issuecomment-661918679 */
@ -636,10 +637,11 @@ static int detect_container_files(void) {
return VIRTUALIZATION_NONE;
}
int detect_container(void) {
static thread_local int cached_found = _VIRTUALIZATION_INVALID;
Virtualization detect_container(void) {
static thread_local Virtualization cached_found = _VIRTUALIZATION_INVALID;
_cleanup_free_ char *m = NULL, *o = NULL, *p = NULL;
const char *e = NULL;
Virtualization v;
int r;
if (cached_found >= 0)
@ -651,7 +653,7 @@ int detect_container(void) {
log_debug_errno(errno, "Failed to check if /proc/vz exists, ignoring: %m");
} else if (access("/proc/bc", F_OK) < 0) {
if (errno == ENOENT) {
r = VIRTUALIZATION_OPENVZ;
v = VIRTUALIZATION_OPENVZ;
goto finish;
}
@ -663,7 +665,7 @@ int detect_container(void) {
if (r < 0)
log_debug_errno(r, "Failed to read /proc/sys/kernel/osrelease, ignoring: %m");
else if (strstr(o, "Microsoft") || strstr(o, "WSL")) {
r = VIRTUALIZATION_WSL;
v = VIRTUALIZATION_WSL;
goto finish;
}
@ -688,7 +690,7 @@ int detect_container(void) {
if (r < 0)
log_debug_errno(r, "Failed to read %s, ignoring: %m", pf);
else if (startswith(ptrace_comm, "proot")) {
r = VIRTUALIZATION_PROOT;
v = VIRTUALIZATION_PROOT;
goto finish;
}
}
@ -715,7 +717,7 @@ int detect_container(void) {
if (!e)
goto check_files;
if (isempty(e)) {
r = VIRTUALIZATION_NONE;
v = VIRTUALIZATION_NONE;
goto finish;
}
@ -746,49 +748,51 @@ check_files:
* for other specific container managers, otherwise we risk mistaking another
* container manager for Docker: the /.dockerenv file could inadvertently end up
* in a file system image. */
r = detect_container_files();
if (r)
v = detect_container_files();
if (v < 0)
return v;
if (v != VIRTUALIZATION_NONE)
goto finish;
r = running_in_cgroupns();
if (r > 0) {
r = VIRTUALIZATION_CONTAINER_OTHER;
v = VIRTUALIZATION_CONTAINER_OTHER;
goto finish;
}
if (r < 0)
log_debug_errno(r, "Failed to detect cgroup namespace: %m");
/* If none of that worked, give up, assume no container manager. */
r = VIRTUALIZATION_NONE;
v = VIRTUALIZATION_NONE;
goto finish;
translate_name:
if (streq(e, "oci")) {
/* Some images hardcode container=oci, but OCI is not a specific container manager.
* Try to detect one based on well-known files. */
r = detect_container_files();
if (!r)
r = VIRTUALIZATION_CONTAINER_OTHER;
v = detect_container_files();
if (v != VIRTUALIZATION_NONE)
v = VIRTUALIZATION_CONTAINER_OTHER;
goto finish;
}
r = container_from_string(e);
if (r < 0)
r = VIRTUALIZATION_CONTAINER_OTHER;
v = container_from_string(e);
if (v < 0)
v = VIRTUALIZATION_CONTAINER_OTHER;
finish:
log_debug("Found container virtualization %s.", virtualization_to_string(r));
cached_found = r;
return r;
log_debug("Found container virtualization %s.", virtualization_to_string(v));
cached_found = v;
return v;
}
int detect_virtualization(void) {
int r;
Virtualization detect_virtualization(void) {
int v;
r = detect_container();
if (r == 0)
r = detect_vm();
v = detect_container();
if (v != VIRTUALIZATION_NONE)
return v;
return r;
return detect_vm();
}
static int userns_has_mapping(const char *name) {
@ -1025,4 +1029,4 @@ static const char *const virtualization_table[_VIRTUALIZATION_MAX] = {
[VIRTUALIZATION_CONTAINER_OTHER] = "container-other",
};
DEFINE_STRING_TABLE_LOOKUP(virtualization, int);
DEFINE_STRING_TABLE_LOOKUP(virtualization, Virtualization);

View File

@ -3,9 +3,10 @@
#include <stdbool.h>
#include "errno-list.h"
#include "macro.h"
enum {
typedef enum Virtualization {
VIRTUALIZATION_NONE = 0,
VIRTUALIZATION_VM_FIRST,
@ -43,23 +44,24 @@ enum {
_VIRTUALIZATION_MAX,
_VIRTUALIZATION_INVALID = -EINVAL,
};
_VIRTUALIZATION_ERRNO_MAX = -ERRNO_MAX, /* ensure full range of errno fits into this enum */
} Virtualization;
static inline bool VIRTUALIZATION_IS_VM(int x) {
static inline bool VIRTUALIZATION_IS_VM(Virtualization x) {
return x >= VIRTUALIZATION_VM_FIRST && x <= VIRTUALIZATION_VM_LAST;
}
static inline bool VIRTUALIZATION_IS_CONTAINER(int x) {
static inline bool VIRTUALIZATION_IS_CONTAINER(Virtualization x) {
return x >= VIRTUALIZATION_CONTAINER_FIRST && x <= VIRTUALIZATION_CONTAINER_LAST;
}
int detect_vm(void);
int detect_container(void);
int detect_virtualization(void);
Virtualization detect_vm(void);
Virtualization detect_container(void);
Virtualization detect_virtualization(void);
int running_in_userns(void);
int running_in_chroot(void);
const char *virtualization_to_string(int v) _const_;
int virtualization_from_string(const char *s) _pure_;
const char *virtualization_to_string(Virtualization v) _const_;
Virtualization virtualization_from_string(const char *s) _pure_;
bool has_cpu_with_flag(const char *flag);

View File

@ -71,7 +71,7 @@ static int property_get_virtualization(
void *userdata,
sd_bus_error *error) {
int v;
Virtualization v;
assert(bus);
assert(reply);

View File

@ -102,7 +102,7 @@ static int parse_argv(int argc, char *argv[]) {
break;
case ARG_LIST:
DUMP_STRING_TABLE(virtualization, int, _VIRTUALIZATION_MAX);
DUMP_STRING_TABLE(virtualization, Virtualization, _VIRTUALIZATION_MAX);
return 0;
case '?':
@ -121,6 +121,7 @@ static int parse_argv(int argc, char *argv[]) {
}
static int run(int argc, char *argv[]) {
Virtualization v;
int r;
/* This is mostly intended to be used for scripts which want
@ -135,15 +136,15 @@ static int run(int argc, char *argv[]) {
switch (arg_mode) {
case ONLY_VM:
r = detect_vm();
if (r < 0)
return log_error_errno(r, "Failed to check for VM: %m");
v = detect_vm();
if (v < 0)
return log_error_errno(v, "Failed to check for VM: %m");
break;
case ONLY_CONTAINER:
r = detect_container();
if (r < 0)
return log_error_errno(r, "Failed to check for container: %m");
v = detect_container();
if (v < 0)
return log_error_errno(v, "Failed to check for container: %m");
break;
case ONLY_CHROOT:
@ -160,16 +161,16 @@ static int run(int argc, char *argv[]) {
case ANY_VIRTUALIZATION:
default:
r = detect_virtualization();
if (r < 0)
return log_error_errno(r, "Failed to check for virtualization: %m");
v = detect_virtualization();
if (v < 0)
return log_error_errno(v, "Failed to check for virtualization: %m");
break;
}
if (!arg_quiet)
puts(virtualization_to_string(r));
puts(virtualization_to_string(v));
return r == VIRTUALIZATION_NONE;
return v == VIRTUALIZATION_NONE;
}
DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(run);

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@ -261,8 +261,9 @@ static bool valid_deployment(const char *deployment) {
static const char* fallback_chassis(void) {
const char *chassis;
_cleanup_free_ char *type = NULL;
Virtualization v;
unsigned t;
int v, r;
int r;
v = detect_virtualization();
if (v < 0)

View File

@ -459,7 +459,8 @@ static int condition_test_group(Condition *c, char **env) {
}
static int condition_test_virtualization(Condition *c, char **env) {
int b, v;
Virtualization v;
int b;
assert(c);
assert(c->parameter);
@ -475,7 +476,7 @@ static int condition_test_virtualization(Condition *c, char **env) {
/* First, compare with yes/no */
b = parse_boolean(c->parameter);
if (b >= 0)
return b == !!v;
return b == (v != VIRTUALIZATION_NONE);
/* Then, compare categorization */
if (streq(c->parameter, "vm"))

View File

@ -1,14 +1,16 @@
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include "architecture.h"
#include "errno-util.h"
#include "log.h"
#include "tests.h"
#include "util.h"
#include "virt.h"
int main(int argc, char *argv[]) {
int a, v;
Virtualization v;
const char *p;
int a;
test_setup_logging(LOG_INFO);
@ -20,7 +22,7 @@ int main(int argc, char *argv[]) {
assert_se(architecture_from_string(architecture_to_string(1)) == 1);
v = detect_virtualization();
if (IN_SET(v, -EPERM, -EACCES))
if (v < 0 && ERRNO_IS_PRIVILEGE(v))
return log_tests_skipped("Cannot detect virtualization");
assert_se(v >= 0);

View File

@ -15,10 +15,11 @@
#include <unistd.h>
#include "barrier.h"
#include "util.h"
#include "errno-util.h"
#include "tests.h"
#include "virt.h"
#include "time-util.h"
#include "util.h"
#include "virt.h"
/* 20ms to test deadlocks; All timings use multiples of this constant as
* alarm/sleep timers. If this timeout is too small for slow machines to perform
@ -434,8 +435,8 @@ static int intro(void) {
* false-positives in CIs.
*/
int v = detect_virtualization();
if (IN_SET(v, -EPERM, -EACCES))
Virtualization v = detect_virtualization();
if (v < 0 && ERRNO_IS_PRIVILEGE(v))
return log_tests_skipped("Cannot detect virtualization");
if (v != VIRTUALIZATION_NONE)