[systemd-devel] [PATCH 2/2] tmpfiles: support globbing for w option
Dave Reisner
dreisner at archlinux.org
Mon Sep 3 14:13:18 PDT 2012
Break out the write logic into a separate function and simply use it as
a callback to glob_item.
This allows users to consolidate writes to sysfs with multiple similar
pathnames, e.g.
w /sys/class/block/sd[a-z]/queue/read_ahead_kb - - - - 1024
---
As is, and even without this patch, the example I point out won't work.
I suspect this is a kernel bug, which I've reported:
https://bugzilla.kernel.org/show_bug.cgi?id=46981
Of course, I'm also happy to provide a workaround here, but I assume that
systemd upstream would rather just have the kernel bug fixed. I haven't
come across any other sysfs nodes (yet) that exhibit this broken behavior.
man/tmpfiles.d.xml | 2 +-
src/tmpfiles/tmpfiles.c | 135 +++++++++++++++++++++++++-----------------------
2 files changed, 72 insertions(+), 65 deletions(-)
diff --git a/man/tmpfiles.d.xml b/man/tmpfiles.d.xml
index b7397b6..c6325a4 100644
--- a/man/tmpfiles.d.xml
+++ b/man/tmpfiles.d.xml
@@ -114,7 +114,7 @@ L /tmp/foobar - - - - /dev/null</programlisting>
<varlistentry>
<term><varname>w</varname></term>
- <listitem><para>Write the argument parameter to a file, if it exists.</para></listitem>
+ <listitem><para>Write the argument parameter to a file, if it exists. Lines of this type accept shell-style globs in place of normal path names.</para></listitem>
</varlistentry>
<varlistentry>
diff --git a/src/tmpfiles/tmpfiles.c b/src/tmpfiles/tmpfiles.c
index e70332c..b44beee 100644
--- a/src/tmpfiles/tmpfiles.c
+++ b/src/tmpfiles/tmpfiles.c
@@ -474,6 +474,75 @@ static int item_set_perms(Item *i, const char *path) {
return label_fix(path, false, false);
}
+static int write_one_file(Item *i, const char *path) {
+ int r, e, fd, flags;
+ struct stat st;
+ mode_t u;
+
+ flags = i->type == CREATE_FILE ? O_CREAT|O_APPEND :
+ i->type == TRUNCATE_FILE ? O_CREAT|O_TRUNC : 0;
+
+ u = umask(0);
+ label_context_set(path, S_IFREG);
+ fd = open(path, flags|O_NDELAY|O_CLOEXEC|O_WRONLY|O_NOCTTY|O_NOFOLLOW, i->mode);
+ e = errno;
+ label_context_clear();
+ umask(u);
+ errno = e;
+
+ if (fd < 0) {
+ if (i->type == WRITE_FILE && errno == ENOENT)
+ return 0;
+
+ log_error("Failed to create file %s: %m", path);
+ return -errno;
+ }
+
+ if (i->argument) {
+ ssize_t n;
+ size_t l;
+ struct iovec iovec[2];
+ static const char new_line = '\n';
+
+ l = strlen(i->argument);
+
+ zero(iovec);
+ iovec[0].iov_base = i->argument;
+ iovec[0].iov_len = l;
+
+ iovec[1].iov_base = (void*) &new_line;
+ iovec[1].iov_len = 1;
+
+ n = writev(fd, iovec, 2);
+
+ /* It's OK if we don't write the trailing
+ * newline, hence we check for l, instead of
+ * l+1 here. Files in /sys often refuse
+ * writing of the trailing newline. */
+ if (n < 0 || (size_t) n < l) {
+ log_error("Failed to write file %s: %s", path, n < 0 ? strerror(-n) : "Short write");
+ close_nointr_nofail(fd);
+ return n < 0 ? n : -EIO;
+ }
+ }
+
+ if (stat(path, &st) < 0) {
+ log_error("stat(%s) failed: %m", path);
+ return -errno;
+ }
+
+ if (!S_ISREG(st.st_mode)) {
+ log_error("%s is not a file.", path);
+ return -EEXIST;
+ }
+
+ r = item_set_perms(i, path);
+ if (r < 0)
+ return r;
+
+ return 0;
+}
+
static int recursive_relabel_children(Item *i, const char *path) {
DIR *d;
int ret = 0;
@@ -607,74 +676,12 @@ static int create_item(Item *i) {
case CREATE_FILE:
case TRUNCATE_FILE:
- case WRITE_FILE: {
- int fd, flags;
-
- flags = i->type == CREATE_FILE ? O_CREAT|O_APPEND :
- i->type == TRUNCATE_FILE ? O_CREAT|O_TRUNC : 0;
-
- u = umask(0);
- label_context_set(i->path, S_IFREG);
- fd = open(i->path, flags|O_NDELAY|O_CLOEXEC|O_WRONLY|O_NOCTTY|O_NOFOLLOW, i->mode);
- e = errno;
- label_context_clear();
- umask(u);
- errno = e;
-
- if (fd < 0) {
- if (i->type == WRITE_FILE && errno == ENOENT)
- break;
-
- log_error("Failed to create file %s: %m", i->path);
- return -errno;
- }
-
- if (i->argument) {
- ssize_t n;
- size_t l;
- struct iovec iovec[2];
- static const char new_line = '\n';
-
- l = strlen(i->argument);
-
- zero(iovec);
- iovec[0].iov_base = i->argument;
- iovec[0].iov_len = l;
-
- iovec[1].iov_base = (void*) &new_line;
- iovec[1].iov_len = 1;
-
- n = writev(fd, iovec, 2);
-
- /* It's OK if we don't write the trailing
- * newline, hence we check for l, instead of
- * l+1 here. Files in /sys often refuse
- * writing of the trailing newline. */
- if (n < 0 || (size_t) n < l) {
- log_error("Failed to write file %s: %s", i->path, n < 0 ? strerror(-n) : "Short write");
- close_nointr_nofail(fd);
- return n < 0 ? n : -EIO;
- }
- }
-
- close_nointr_nofail(fd);
-
- if (stat(i->path, &st) < 0) {
- log_error("stat(%s) failed: %m", i->path);
- return -errno;
- }
-
- if (!S_ISREG(st.st_mode)) {
- log_error("%s is not a file.", i->path);
- return -EEXIST;
- }
-
- r = item_set_perms(i, i->path);
+ case WRITE_FILE:
+ r = glob_item(i, write_one_file);
if (r < 0)
return r;
break;
- }
case TRUNCATE_DIRECTORY:
case CREATE_DIRECTORY:
--
1.7.12
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