Merge pull request #7983 from poettering/tmpfiles-eexist

make "f" tmpfiles.d behaviour work like documentation suggests + coccinelle fixes

NEWS

@@ -7,6 +7,18 @@ CHANGES WITH 237 in spe:
           keycodes are not recognized by any major desktop. They now produce
           Up/Down key events so that they can be used for scrolling.
 
+        * INCOMPATIBILITY: systemd-tmpfiles' "f" lines changed behaviour
+          slightly: previously, if an argument was specified for lines of this
+          type (i.e. the right-most column was set) this string was appended to
+          existing files each time systemd-tmpfiles was run. This behaviour was
+          different from what the documentation said, and not particularly
+          useful, as repeated systemd-tmpfiles invocations would not be
+          idempotent and grow such files without bounds. With this release
+          behaviour has been altered slightly, to match what the documentation
+          says: lines of this type only have an effect if the indicated files
+          don't exist yet, and only then the argument string is written to the
+          file.
+
         — Berlin, 2018-XX-XX
 
 CHANGES WITH 236:

coccinelle/o-ndelay.occi

@@ -0,0 +1,4 @@
+@@
+@@
+- O_NDELAY
++ O_NONBLOCK

man/tmpfiles.d.xml

@@ -147,9 +147,8 @@ L     /tmp/foobar -    -    -    -   /dev/null</programlisting>
       <variablelist>
         <varlistentry>
           <term><varname>f</varname></term>
-          <listitem><para>Create a file if it does not exist yet. If
+          <listitem><para>Create a file if it does not exist yet. If the argument parameter is given and the file did
-          the argument parameter is given, it will be written to the
+          not exist yet, it will be written to the file. Does not follow symlinks.</para></listitem>
-          file. Does not follow symlinks.</para></listitem>
         </varlistentry>
 
         <varlistentry>
@@ -585,21 +584,14 @@ r! /tmp/.X[0-9]*-lock</programlisting>
     <refsect2>
       <title>Argument</title>
 
-      <para>For <varname>L</varname> lines determines the destination
+      <para>For <varname>L</varname> lines determines the destination path of the symlink. For <varname>c</varname> and
-      path of the symlink. For <varname>c</varname> and
+      <varname>b</varname>, determines the major/minor of the device node, with major and minor formatted as integers,
-      <varname>b</varname>, determines the major/minor of the device
+      separated by <literal>:</literal>, e.g.  <literal>1:3</literal>. For <varname>f</varname>, <varname>F</varname>,
-      node, with major and minor formatted as integers, separated by
+      and <varname>w</varname>, the argument may be used to specify a short string that is written to the file,
-      <literal>:</literal>, e.g.  <literal>1:3</literal>. For
+      suffixed by a newline. For <varname>C</varname>, specifies the source file or directory. For <varname>t</varname>
-      <varname>f</varname>, <varname>F</varname>, and
+      and <varname>T</varname>, determines extended attributes to be set. For <varname>a</varname> and
-      <varname>w</varname>, the argument may be used to specify a short string that
+      <varname>A</varname>, determines ACL attributes to be set. For <varname>h</varname> and <varname>H</varname>,
-      is written to the file, suffixed by a newline. For
+      determines the file attributes to set. Ignored for all other lines.</para>
-      <varname>C</varname>, specifies the source file or
-      directory. For <varname>t</varname> and <varname>T</varname>,
-      determines extended attributes to be set. For
-      <varname>a</varname> and <varname>A</varname>, determines ACL
-      attributes to be set. For <varname>h</varname> and
-      <varname>H</varname>, determines the file attributes to
-      set. Ignored for all other lines.</para>
 
       <para>This field can contain specifiers, see below.</para>
     </refsect2>

src/journal/journald-server.c

@@ -1497,7 +1497,8 @@ static int server_open_hostname(Server *s) {
 
         assert(s);
 
-        s->hostname_fd = open("/proc/sys/kernel/hostname", O_RDONLY|O_CLOEXEC|O_NDELAY|O_NOCTTY);
+        s->hostname_fd = open("/proc/sys/kernel/hostname",
+                              O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
         if (s->hostname_fd < 0)
                 return log_error_errno(errno, "Failed to open /proc/sys/kernel/hostname: %m");
 

src/login/logind-inhibit.c

@@ -305,7 +305,7 @@ int inhibitor_create_fifo(Inhibitor *i) {
 
         /* Open reading side */
         if (i->fifo_fd < 0) {
-                i->fifo_fd = open(i->fifo_path, O_RDONLY|O_CLOEXEC|O_NDELAY);
+                i->fifo_fd = open(i->fifo_path, O_RDONLY|O_CLOEXEC|O_NONBLOCK);
                 if (i->fifo_fd < 0)
                         return -errno;
         }
@@ -321,7 +321,7 @@ int inhibitor_create_fifo(Inhibitor *i) {
         }
 
         /* Open writing side */
-        r = open(i->fifo_path, O_WRONLY|O_CLOEXEC|O_NDELAY);
+        r = open(i->fifo_path, O_WRONLY|O_CLOEXEC|O_NONBLOCK);
         if (r < 0)
                 return -errno;
 

src/login/logind-session.c

@@ -962,7 +962,7 @@ int session_create_fifo(Session *s) {
 
         /* Open reading side */
         if (s->fifo_fd < 0) {
-                s->fifo_fd = open(s->fifo_path, O_RDONLY|O_CLOEXEC|O_NDELAY);
+                s->fifo_fd = open(s->fifo_path, O_RDONLY|O_CLOEXEC|O_NONBLOCK);
                 if (s->fifo_fd < 0)
                         return -errno;
 
@@ -981,7 +981,7 @@ int session_create_fifo(Session *s) {
         }
 
         /* Open writing side */
-        r = open(s->fifo_path, O_WRONLY|O_CLOEXEC|O_NDELAY);
+        r = open(s->fifo_path, O_WRONLY|O_CLOEXEC|O_NONBLOCK);
         if (r < 0)
                 return -errno;
 

src/resolve/resolved-manager.c

@@ -488,7 +488,8 @@ static int manager_watch_hostname(Manager *m) {
 
         assert(m);
 
-        m->hostname_fd = open("/proc/sys/kernel/hostname", O_RDONLY|O_CLOEXEC|O_NDELAY|O_NOCTTY);
+        m->hostname_fd = open("/proc/sys/kernel/hostname",
+                              O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY);
         if (m->hostname_fd < 0) {
                 log_warning_errno(errno, "Failed to watch hostname: %m");
                 return 0;

src/shared/bus-unit-util.c

@@ -1382,7 +1382,7 @@ static int bus_append_socket_property(sd_bus_message *m, const char *field, cons
                 if (isempty(eq))
                         r = sd_bus_message_append(m, "(sv)", "Listen", "a(ss)", 0);
                 else
-                        r = sd_bus_message_append(m, "(sv)", "Listen", "a(ss)", 1, field + strlen("Listen"), eq);
+                        r = sd_bus_message_append(m, "(sv)", "Listen", "a(ss)", 1, field + STRLEN("Listen"), eq);
                 if (r < 0)
                         return bus_log_create_error(r);
 

src/shared/utmp-wtmp.c

@@ -330,7 +330,7 @@ static int write_to_terminal(const char *tty, const char *message) {
         assert(tty);
         assert(message);
 
-        fd = open(tty, O_WRONLY|O_NDELAY|O_NOCTTY|O_CLOEXEC);
+        fd = open(tty, O_WRONLY|O_NONBLOCK|O_NOCTTY|O_CLOEXEC);
         if (fd < 0 || !isatty(fd))
                 return -errno;
 

src/systemctl/systemctl.c

@@ -8352,7 +8352,7 @@ static int talk_initctl(void) {
 
         request.runlevel = rl;
 
-        fd = open(INIT_FIFO, O_WRONLY|O_NDELAY|O_CLOEXEC|O_NOCTTY);
+        fd = open(INIT_FIFO, O_WRONLY|O_NONBLOCK|O_CLOEXEC|O_NOCTTY);
         if (fd < 0) {
                 if (errno == ENOENT)
                         return 0;

src/tmpfiles/tmpfiles.c

@@ -1189,7 +1189,7 @@ static int write_one_file(Item *i, const char *path) {
         assert(i);
         assert(path);
 
-        flags = i->type == CREATE_FILE ? O_CREAT|O_APPEND|O_NOFOLLOW :
+        flags = i->type == CREATE_FILE ? O_CREAT|O_EXCL|O_NOFOLLOW :
                 i->type == TRUNCATE_FILE ? O_CREAT|O_TRUNC|O_NOFOLLOW : 0;
 
         RUN_WITH_UMASK(0000) {
@@ -1200,9 +1200,13 @@ static int write_one_file(Item *i, const char *path) {
 
         if (fd < 0) {
                 if (i->type == WRITE_FILE && errno == ENOENT) {
-                        log_debug_errno(errno, "Not writing \"%s\": %m", path);
+                        log_debug_errno(errno, "Not writing missing file \"%s\": %m", path);
                         return 0;
                 }
+                if (i->type == CREATE_FILE && errno == EEXIST) {
+                        log_debug_errno(errno, "Not writing to pre-existing file \"%s\": %m", path);
+                        goto done;
+                }
 
                 r = -errno;
                 if (!i->argument && errno == EROFS && stat(path, &st) == 0 &&
@@ -1223,6 +1227,7 @@ static int write_one_file(Item *i, const char *path) {
 
         fd = safe_close(fd);
 
+done:
         if (stat(path, &st) < 0)
                 return log_error_errno(errno, "stat(%s) failed: %m", path);