amxp_syssig.c

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#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
 
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
 
#include <amxc/amxc_macros.h>
#include <amxc/amxc.h>
#include <amxp/amxp.h>
 
static int sig_fd = -1;
static sigset_t mask;
 
int amxp_syssig_enable(const int sigid, const bool enable) {
    int retval = -1;
    amxp_signal_t* signal = NULL;
    sigset_t change_mask;
    when_true(sigid > AMXP_SYSSIG_MAX, exit);
    when_true(sigid == SIGKILL || sigid == SIGSTOP, exit);
 
    sigemptyset(&change_mask);
    sigaddset(&change_mask, sigid);
 
    amxp_signal_new(NULL, &signal, strsignal(sigid));
 
    if(enable) {
        when_failed(sigprocmask(SIG_BLOCK, &change_mask, NULL), exit);
        sigaddset(&mask, sigid);
    } else {
        when_failed(sigprocmask(SIG_UNBLOCK, &change_mask, NULL), exit);
        sigdelset(&mask, sigid);
    }
 
    sig_fd = signalfd(sig_fd, &mask, SFD_NONBLOCK | SFD_CLOEXEC);
    retval = 0;
 
exit:
    return retval;
}
 
bool amxp_syssig_is_enabled(const int sigid) {
    bool enabled = false;
    int inset = -1;
    when_true(sigid > AMXP_SYSSIG_MAX, exit);
 
    inset = sigismember(&mask, sigid);
    when_true(inset < 0, exit);
 
    enabled = (inset == 1);
exit:
    return enabled;
}
 
int amxp_syssig_get_fd(void) {
    return sig_fd;
}
 
int amxp_syssig_read(void) {
    int retval = -1;
    struct signalfd_siginfo si;
    ssize_t res = 0;
    amxc_var_t sig_var;
    int len = sizeof(amxp_siginfo_t);
    amxp_signal_t* signal = NULL;
 
    amxc_var_init(&sig_var);
 
    res = read(sig_fd, &si, len);
    when_true(res != len, exit);
 
    amxc_var_set(amxp_siginfo_t, &sig_var, &si);
 
    signal = amxp_sigmngr_find_signal(NULL, strsignal(si.ssi_signo));
    when_null(signal, exit);
    amxp_signal_trigger(signal, &sig_var);
 
    retval = 0;
 
exit:
    amxc_var_clean(&sig_var);
    return retval;
}
 
CONSTRUCTOR_LVL(200) static void amxp_syssig_init(void) {
    sigemptyset(&mask);
    sig_fd = signalfd(sig_fd, &mask, SFD_NONBLOCK | SFD_CLOEXEC);
}
 
DESTRUCTOR_LVL(200) static void amxp_syssig_cleanup(void) {
    close(sig_fd);
    sigemptyset(&mask);
}