update TODO

[elogind.git] / CODING_STYLE

diff --git a/CODING_STYLE b/CODING_STYLE
index 1d1d97049257332671706b1810169feabc1000c4..1748dc4bc4d705e33dcf9ac43bac64a8f7727569 100644 (file)
--- a/CODING_STYLE
+++ b/CODING_STYLE
@@ -202,3 +202,33 @@
   b) socket() and socketpair() must get SOCK_CLOEXEC passed
   c) recvmsg() must get MSG_CMSG_CLOEXEC set
   d) F_DUPFD_CLOEXEC should be used instead of F_DUPFD, and so on
+
+- We never use the XDG version of basename(). glibc defines it in
+  libgen.h. The only reason to include that file is because dirname()
+  is needed. Everytime you need that please immediately undefine
+  basename(), and add a comment about it, so that no code ever ends up
+  using the XDG version!
+
+- Use the bool type for booleans, not integers. One exception: in public
+  headers (i.e those in src/systemd/sd-*.h) use integers after all, as "bool"
+  is C99 and in our public APIs we try to stick to C89 (with a few extension).
+
+- When you invoke certain calls like unlink(), or mkdir_p() and you
+  know it is safe to ignore the error it might return (because a later
+  call would detect the failure anyway, or because the error is in an
+  error path and you thus couldn't do anything about it anyway), then
+  make this clear by casting the invocation explicitly to (void). Code
+  checks like Coverity understand that, and will not complain about
+  ignored error codes. Hence, please use this:
+
+      (void) unlink("/foo/bar/baz");
+
+  instead of just this:
+
+      unlink("/foo/bar/baz");
+
+- Don't invoke exit(), ever. It is not replacement for proper error
+  handling. Please escalate errors up your call chain, and use normal
+  "return" to exit from the main function of a process. If you
+  fork()ed off a child process, please use _exit() instead of exit(),
+  so that the exit handlers are not run.