diff options
| author | David Lamparter <equinox@diac24.net> | 2021-02-04 22:25:49 +0100 |
|---|---|---|
| committer | David Lamparter <equinox@diac24.net> | 2021-02-12 19:28:22 +0100 |
| commit | 6e3253b9790bdb22eff3b74b940c8c20d8cbea2c (patch) | |
| tree | 7d13c7c0c4e251f39e93858d061f5e50d6a82269 | |
| parent | 35da69f1545446ecd9981b5d5fd5f3b4d912e50a (diff) | |
lib: memorize what fds were open at startup
... in case the user does something like `zebra 3>logfile`. Also useful
for some module purposes, maybe even feeding config at some point in the
future.
Signed-off-by: David Lamparter <equinox@diac24.net>
| -rw-r--r-- | lib/libfrr.c | 23 | ||||
| -rw-r--r-- | lib/libfrr.h | 3 |
2 files changed, 25 insertions, 1 deletions
diff --git a/lib/libfrr.c b/lib/libfrr.c index b83883779c..51b97369c9 100644 --- a/lib/libfrr.c +++ b/lib/libfrr.c @@ -71,6 +71,7 @@ static char vtypath_default[512]; bool debug_memstats_at_exit = false; static bool nodetach_term, nodetach_daemon; +static uint64_t startup_fds; static char comb_optstr[256]; static struct option comb_lo[64]; @@ -341,6 +342,28 @@ void frr_preinit(struct frr_daemon_info *daemon, int argc, char **argv) strlcpy(frr_protonameinst, di->logname, sizeof(frr_protonameinst)); di->cli_mode = FRR_CLI_CLASSIC; + + /* we may be starting with extra FDs open for whatever purpose, + * e.g. logging, some module, etc. Recording them here allows later + * checking whether an fd is valid for such extension purposes, + * without this we could end up e.g. logging to a BGP session fd. + */ + startup_fds = 0; + for (int i = 0; i < 64; i++) { + struct stat st; + + if (fstat(i, &st)) + continue; + if (S_ISDIR(st.st_mode) || S_ISBLK(st.st_mode)) + continue; + + startup_fds |= UINT64_C(0x1) << (uint64_t)i; + } +} + +bool frr_is_startup_fd(int fd) +{ + return !!(startup_fds & (UINT64_C(0x1) << (uint64_t)fd)); } void frr_opt_add(const char *optstr, const struct option *longopts, diff --git a/lib/libfrr.h b/lib/libfrr.h index c446931468..825f502bdf 100644 --- a/lib/libfrr.h +++ b/lib/libfrr.h @@ -138,7 +138,8 @@ extern __attribute__((__noreturn__)) void frr_help_exit(int status); extern struct thread_master *frr_init(void); extern const char *frr_get_progname(void); extern enum frr_cli_mode frr_get_cli_mode(void); -uint32_t frr_get_fd_limit(void); +extern uint32_t frr_get_fd_limit(void); +extern bool frr_is_startup_fd(int fd); DECLARE_HOOK(frr_late_init, (struct thread_master * tm), (tm)) DECLARE_HOOK(frr_very_late_init, (struct thread_master * tm), (tm)) |