Re: [libvirt PATCH 04/17] util: Introduce virProcess{Get,Set}Limit()

These functions abstract part of the existing logic, which is the same in all virProcessSetMax*() functions, and changes it so that which underlying syscall is used depends on their availability rather than on the context in which they are called: since prlimit() and {g,s}etrlimit() have slightly different requirements, using the same one every single time should make for a more consistent experience. As part of the change, we also remove the special case for passing zero to virProcessSetMax*() functions: we have removed all callers that depended on that functionality in the previous commit, so this is now safe to do and makes the semantics simpler. This commit is better viewed with 'git show -w'. Signed-off-by: Andrea Bolognani <abologna(a)redhat.com&gt; --- src/util/virprocess.c | 175 +++++++++++++++++++++++------------------- 1 file changed, 95 insertions(+), 80 deletions(-) diff --git a/src/util/virprocess.c b/src/util/virprocess.c index e01ff25540..38b248217e 100644 --- a/src/util/virprocess.c +++ b/src/util/virprocess.c @@ -738,10 +738,66 @@ virProcessPrLimit(pid_t pid G_GNUC_UNUSED, } #endif +#if WITH_GETRLIMIT +static int +virProcessGetRLimit(int resource, + struct rlimit *old_limit) +{ + return getrlimit(resource, old_limit); +} +#endif /* WITH_GETRLIMIT */ + +#if WITH_SETRLIMIT +static int +virProcessSetRLimit(int resource, + const struct rlimit *new_limit) +{ + return setrlimit(resource, new_limit); +} +#endif /* WITH_SETRLIMIT */ + +#if WITH_GETRLIMIT

+static int +virProcessGetLimit(pid_t pid, + int resource, + struct rlimit *old_limit) +{ + pid_t current_pid = getpid(); + bool same_process = (pid == current_pid); + + if (virProcessPrLimit(pid, resource, NULL, old_limit) == 0) + return 0; + + if (same_process && virProcessGetRLimit(resource, old_limit) == 0) + return 0; + + return -1; +} +#endif /* WITH_GETRLIMIT */ + +#if WITH_SETRLIMIT

+static int +virProcessSetLimit(pid_t pid, + int resource, + const struct rlimit *new_limit) +{ + pid_t current_pid = getpid(); + bool same_process = (pid == current_pid); + + if (virProcessPrLimit(pid, resource, new_limit, NULL) == 0) + return 0; + + if (same_process && virProcessSetRLimit(resource, new_limit) == 0) + return 0; + + return -1; +} +#endif /* WITH_SETRLIMIT */ +