vircgroupmock: rewrite cgroup fopen mocking

Move all the cgroup data into separate files out of vircgroupmock.c
and rework the fopen function to load data from files.  This will
make it easier to add more test cases.
Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

tests/vircgroupdata/all-in-one.cgroups

+#subsys_name    hierarchy       num_cgroups     enabled
+cpuset   6   1  1
+cpu      6   1  1
+cpuacct  6   1  1
+memory   6   1  1
+devices  6   1  1
+blkio    6   1  1

tests/vircgroupdata/all-in-one.mounts

@@ -4,4 +4,4 @@ proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0
 udev /dev devtmpfs rw,relatime,size=16458560k,nr_inodes=4114640,mode=755 0 0
 devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0
 nfsd /proc/fs/nfsd nfsd rw,relatime 0 0
-cgroup /sys/fs/cgroup cgroup rw,relatime,blkio,devices,memory,cpuacct,cpu,cpuset 0 0
+cgroup /not/really/sys/fs/cgroup cgroup rw,relatime,blkio,devices,memory,cpuacct,cpu,cpuset 0 0

tests/vircgroupdata/all-in-one.parsed

-cpu          /sys/fs/cgroup
-cpuacct      /sys/fs/cgroup
-cpuset       /sys/fs/cgroup
-memory       /sys/fs/cgroup
-devices      /sys/fs/cgroup
+cpu          /not/really/sys/fs/cgroup
+cpuacct      /not/really/sys/fs/cgroup
+cpuset       /not/really/sys/fs/cgroup
+memory       /not/really/sys/fs/cgroup
+devices      /not/really/sys/fs/cgroup
 freezer      <null>
-blkio        /sys/fs/cgroup
+blkio        /not/really/sys/fs/cgroup
 net_cls      <null>
 perf_event   <null>
 name=systemd <null>

tests/vircgroupdata/all-in-one.self.cgroup

+6:blkio,devices,memory,cpuacct,cpu,cpuset:/

tests/vircgroupdata/logind.cgroups

+#subsys_name    hierarchy       num_cgroups     enabled
+cpuset    0  1  1
+cpu       0  1  1
+cpuacct   0  1  1
+memory    0  1  0
+devices   0  1  1
+freezer   0  1  1
+net_cls   0  1  1
+blkio     0  1  1
+perf_event  0  1  1

tests/vircgroupdata/logind.mounts

+none /not/really/sys/fs/cgroup tmpfs rw,rootcontext=system_u:object_r:sysfs_t:s0,seclabel,relatime,size=4k,mode=755 0 0
+systemd /not/really/sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,name=systemd 0 0

tests/vircgroupdata/logind.self.cgroup

+0:name=systemd:/

tests/vircgroupdata/systemd.cgroups

+#subsys_name    hierarchy       num_cgroups     enabled
+cpuset  2       4       1
+cpu     3       48      1
+cpuacct 3       48      1
+memory  4       4       1
+devices 5       4       1
+freezer 6       4       1
+blkio   8       4       1

tests/vircgroupdata/systemd.mounts

+rootfs / rootfs rw 0 0
+tmpfs /run tmpfs rw,seclabel,nosuid,nodev,mode=755 0 0
+tmpfs /not/really/sys/fs/cgroup tmpfs rw,seclabel,nosuid,nodev,noexec,mode=755 0 0
+cgroup /not/really/sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd 0 0
+cgroup /not/really/sys/fs/cgroup/cpuset cgroup rw,nosuid,nodev,noexec,relatime,cpuset 0 0
+cgroup /not/really/sys/fs/cgroup/cpu,cpuacct cgroup rw,nosuid,nodev,noexec,relatime,cpuacct,cpu 0 0
+cgroup /not/really/sys/fs/cgroup/freezer cgroup rw,nosuid,nodev,noexec,relatime,freezer 0 0
+cgroup /not/really/sys/fs/cgroup/blkio cgroup rw,nosuid,nodev,noexec,relatime,blkio 0 0
+cgroup /not/really/sys/fs/cgroup/memory cgroup rw,nosuid,nodev,noexec,relatime,memory 0 0
+/dev/sda1 /boot ext4 rw,seclabel,relatime,data=ordered 0 0
+tmpfs /tmp tmpfs rw,seclabel,relatime,size=1024000k 0 0

tests/vircgroupdata/systemd.self.cgroup

+115:memory:/
+8:blkio:/
+6:freezer:/
+3:cpuacct,cpu:/system
+2:cpuset:/
+1:name=systemd:/user/berrange/123

tests/vircgroupmock.c

@@ -79,85 +79,6 @@ const char *fakedevicedir1 = FAKEDEVDIR1;
  * of files beneath it
  */
 
-/*
- * Intentionally missing the 'devices' mount.
- * Co-mounting cpu & cpuacct controllers
- * An anonymous controller for systemd
- */
-const char *procmounts =
-    "rootfs / rootfs rw 0 0\n"
-    "tmpfs /run tmpfs rw,seclabel,nosuid,nodev,mode=755 0 0\n"
-    "tmpfs /not/really/sys/fs/cgroup tmpfs rw,seclabel,nosuid,nodev,noexec,mode=755 0 0\n"
-    "cgroup /not/really/sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,release_agent=/usr/lib/systemd/systemd-cgroups-agent,name=systemd 0 0\n"
-    "cgroup /not/really/sys/fs/cgroup/cpuset cgroup rw,nosuid,nodev,noexec,relatime,cpuset 0 0\n"
-    "cgroup /not/really/sys/fs/cgroup/cpu,cpuacct cgroup rw,nosuid,nodev,noexec,relatime,cpuacct,cpu 0 0\n"
-    "cgroup /not/really/sys/fs/cgroup/freezer cgroup rw,nosuid,nodev,noexec,relatime,freezer 0 0\n"
-    "cgroup /not/really/sys/fs/cgroup/blkio cgroup rw,nosuid,nodev,noexec,relatime,blkio 0 0\n"
-    "cgroup /not/really/sys/fs/cgroup/memory cgroup rw,nosuid,nodev,noexec,relatime,memory 0 0\n"
-    "/dev/sda1 /boot ext4 rw,seclabel,relatime,data=ordered 0 0\n"
-    "tmpfs /tmp tmpfs rw,seclabel,relatime,size=1024000k 0 0\n";
-
-const char *procselfcgroups =
-    "115:memory:/\n"
-    "8:blkio:/\n"
-    "6:freezer:/\n"
-    "3:cpuacct,cpu:/system\n"
-    "2:cpuset:/\n"
-    "1:name=systemd:/user/berrange/123\n";
-
-const char *proccgroups =
-    "#subsys_name    hierarchy       num_cgroups     enabled\n"
-    "cpuset  2       4       1\n"
-    "cpu     3       48      1\n"
-    "cpuacct 3       48      1\n"
-    "memory  4       4       1\n"
-    "devices 5       4       1\n"
-    "freezer 6       4       1\n"
-    "blkio   8       4       1\n";
-
-
-const char *procmountsallinone =
-    "rootfs / rootfs rw 0 0\n"
-    "sysfs /sys sysfs rw,nosuid,nodev,noexec,relatime 0 0\n"
-    "proc /proc proc rw,nosuid,nodev,noexec,relatime 0 0\n"
-    "udev /dev devtmpfs rw,relatime,size=16458560k,nr_inodes=4114640,mode=755 0 0\n"
-    "devpts /dev/pts devpts rw,nosuid,noexec,relatime,gid=5,mode=620,ptmxmode=000 0 0\n"
-    "nfsd /proc/fs/nfsd nfsd rw,relatime 0 0\n"
-    "cgroup /not/really/sys/fs/cgroup cgroup rw,relatime,blkio,devices,memory,cpuacct,cpu,cpuset 0 0\n";
-
-const char *procselfcgroupsallinone =
-    "6:blkio,devices,memory,cpuacct,cpu,cpuset:/";
-
-const char *proccgroupsallinone =
-    "#subsys_name    hierarchy       num_cgroups     enabled\n"
-    "cpuset   6   1  1\n"
-    "cpu      6   1  1\n"
-    "cpuacct  6   1  1\n"
-    "memory   6   1  1\n"
-    "devices  6   1  1\n"
-    "blkio    6   1  1\n";
-
-const char *procmountslogind =
-    "none /not/really/sys/fs/cgroup tmpfs rw,rootcontext=system_u:object_r:sysfs_t:s0,seclabel,relatime,size=4k,mode=755 0 0\n"
-    "systemd /not/really/sys/fs/cgroup/systemd cgroup rw,nosuid,nodev,noexec,relatime,name=systemd 0 0\n";
-
-const char *procselfcgroupslogind =
-    "1:name=systemd:/\n";
-
-const char *proccgroupslogind =
-    "#subsys_name    hierarchy       num_cgroups     enabled\n"
-    "cpuset    0  1  1\n"
-    "cpu       0  1  1\n"
-    "cpuacct   0  1  1\n"
-    "memory    0  1  0\n"
-    "devices   0  1  1\n"
-    "freezer   0  1  1\n"
-    "net_cls   0  1  1\n"
-    "blkio     0  1  1\n"
-    "perf_event  0  1  1\n";
-
-
-
 static int make_file(const char *path,
                      const char *name,
                      const char *value)
@@ -377,29 +298,16 @@ static void init_sysfs(void)
 
 FILE *fopen(const char *path, const char *mode)
 {
-    const char *mock;
-    bool allinone = false, logind = false;
-    init_syms();
+    char *filepath = NULL;
+    const char *type = NULL;
+    FILE *rc = NULL;
+    const char *filename = getenv("VIR_CGROUP_MOCK_FILENAME");
 
-    mock = getenv("VIR_CGROUP_MOCK_MODE");
-    if (mock) {
-        if (STREQ(mock, "allinone"))
-            allinone = true;
-        else if (STREQ(mock, "logind"))
-            logind = true;
-    }
+    init_syms();
 
     if (STREQ(path, "/proc/mounts")) {
         if (STREQ(mode, "r")) {
-            if (allinone)
-                return fmemopen((void *)procmountsallinone,
-                                strlen(procmountsallinone) + 1, mode);
-            else if (logind)
-                return fmemopen((void *)procmountslogind,
-                                strlen(procmountslogind) + 1, mode);
-            else
-                return fmemopen((void *)procmounts,
-                                strlen(procmounts) + 1, mode);
+            type = "mounts";
         } else {
             errno = EACCES;
             return NULL;
@@ -407,15 +315,7 @@ FILE *fopen(const char *path, const char *mode)
     }
     if (STREQ(path, "/proc/cgroups")) {
         if (STREQ(mode, "r")) {
-            if (allinone)
-                return fmemopen((void *)proccgroupsallinone,
-                                strlen(proccgroupsallinone) + 1, mode);
-            else if (logind)
-                return fmemopen((void *)proccgroupslogind,
-                                strlen(proccgroupslogind) + 1, mode);
-            else
-                return fmemopen((void *)proccgroups,
-                                strlen(proccgroups) + 1, mode);
+            type = "cgroups";
         } else {
             errno = EACCES;
             return NULL;
@@ -423,21 +323,25 @@ FILE *fopen(const char *path, const char *mode)
     }
     if (STREQ(path, "/proc/self/cgroup")) {
         if (STREQ(mode, "r")) {
-            if (allinone)
-                return fmemopen((void *)procselfcgroupsallinone,
-                                strlen(procselfcgroupsallinone) + 1, mode);
-            else if (logind)
-                return fmemopen((void *)procselfcgroupslogind,
-                                strlen(procselfcgroupslogind) + 1, mode);
-            else
-                return fmemopen((void *)procselfcgroups,
-                                strlen(procselfcgroups) + 1, mode);
+            type = "self.cgroup";
         } else {
             errno = EACCES;
             return NULL;
         }
     }
 
+    if (type) {
+        if (!filename)
+            abort();
+        if (virAsprintfQuiet(&filepath, "%s/vircgroupdata/%s.%s",
+                             abs_srcdir, filename, type) < 0) {
+            abort();
+        }
+        rc = real_fopen(filepath, mode);
+        free(filepath);
+        return rc;
+    }
+
     return real_fopen(path, mode);
 }
 

tests/vircgrouptest.c

@@ -889,6 +889,7 @@ mymain(void)
     DETECT_MOUNTS("no-cgroups");
     DETECT_MOUNTS("kubevirt");
 
+    setenv("VIR_CGROUP_MOCK_FILENAME", "systemd", 1);
     if (virTestRun("New cgroup for self", testCgroupNewForSelf, NULL) < 0)
         ret = -1;
 
@@ -924,20 +925,21 @@ mymain(void)
 
     if (virTestRun("virCgroupGetPercpuStats works", testCgroupGetPercpuStats, NULL) < 0)
         ret = -1;
+    unsetenv("VIR_CGROUP_MOCK_FILENAME");
 
-    setenv("VIR_CGROUP_MOCK_MODE", "allinone", 1);
+    setenv("VIR_CGROUP_MOCK_FILENAME", "all-in-one", 1);
     if (virTestRun("New cgroup for self (allinone)", testCgroupNewForSelfAllInOne, NULL) < 0)
         ret = -1;
     if (virTestRun("Cgroup available", testCgroupAvailable, (void*)0x1) < 0)
         ret = -1;
-    unsetenv("VIR_CGROUP_MOCK_MODE");
+    unsetenv("VIR_CGROUP_MOCK_FILENAME");
 
-    setenv("VIR_CGROUP_MOCK_MODE", "logind", 1);
+    setenv("VIR_CGROUP_MOCK_FILENAME", "logind", 1);
     if (virTestRun("New cgroup for self (logind)", testCgroupNewForSelfLogind, NULL) < 0)
         ret = -1;
     if (virTestRun("Cgroup available", testCgroupAvailable, (void*)0x0) < 0)
         ret = -1;
-    unsetenv("VIR_CGROUP_MOCK_MODE");
+    unsetenv("VIR_CGROUP_MOCK_FILENAME");
 
     if (getenv("LIBVIRT_SKIP_CLEANUP") == NULL)
         virFileDeleteTree(fakerootdir);