amxp_proc_ctrl.c

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#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
 
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <limits.h>
#include <sys/inotify.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
 
#include <amxc/amxc.h>
#include <amxc/amxc_macros.h>
#include <amxp/amxp.h>
 
#define PROC_CHILDREN "/proc/%d/task/%d/children"
 
static void amxp_proc_ctrl_free_char(amxc_array_it_t* it) {
    char* txt = (char*) amxc_array_it_get_data(it);
    free(txt);
}
 
static void amxp_proc_ctrl_timer_callback(UNUSED amxp_timer_t* const timer,
                                          void* data) {
    amxp_proc_ctrl_t* proc = (amxp_proc_ctrl_t*) data;
    amxc_var_t pid;
    amxc_var_init(&pid);
    amxc_var_set(uint32_t, &pid, proc->proc->pid);
    amxp_sigmngr_emit_signal(NULL, "proc:disable", &pid);
    amxp_proc_ctrl_stop(proc);
 
    amxc_var_clean(&pid);
}
 
static void amxp_proc_ctrl_stopped(UNUSED const char* const event_name,
                                   UNUSED const amxc_var_t* const event_data,
                                   void* const priv) {
    amxp_proc_ctrl_t* proc = (amxp_proc_ctrl_t*) priv;
    amxc_var_t pid;
    amxc_var_init(&pid);
 
    when_null(proc, leave);
 
    amxc_var_set(uint32_t, &pid, proc->proc->pid);
    amxp_timer_stop(proc->timer);
    amxp_proc_ctrl_stop_childs(proc);
 
    amxp_sigmngr_emit_signal(NULL, "proc:stopped", &pid);
 
leave:
    amxc_var_clean(&pid);
}
 
static int amxp_proc_ctrl_get_child_pids_proc_children(amxp_proc_ctrl_t* proc) {
    int retval = -1;
    FILE* fp = NULL;
    amxc_string_t file;
    pid_t ppid = 0;
    ssize_t read = 0;
    char* line = NULL;
    size_t len = 0;
 
    amxc_string_init(&file, 0);
 
    ppid = amxp_subproc_get_pid(proc->proc);
    amxc_var_set_type(&proc->child_proc_pids, AMXC_VAR_ID_LIST);
 
    amxc_string_setf(&file, PROC_CHILDREN, ppid, ppid);
    fp = fopen(amxc_string_get(&file, 0), "r");
    if(fp == NULL) {
        goto leave;
    }
 
    read = getline(&line, &len, fp);
    if(read == -1) {
        free(line);
        goto leave;
    }
 
    amxc_var_push(ssv_string_t, &proc->child_proc_pids, line);
    amxc_var_cast(&proc->child_proc_pids, AMXC_VAR_ID_LIST);
 
    retval = 0;
 
leave:
    if(fp != NULL) {
        fclose(fp);
    }
    amxc_string_clean(&file);
    return retval;
}
 
static int amxp_proc_ctrl_get_child_pids_scan_proc(amxp_proc_ctrl_t* proc) {
    int retval = -1;
    amxc_llist_t children;
 
    amxc_llist_init(&children);
    retval = amxp_proci_findf(&children,
                              "ppid == %d", amxp_subproc_get_pid(proc->proc));
 
    when_failed(retval, leave);
    amxc_var_set_type(&proc->child_proc_pids, AMXC_VAR_ID_LIST);
 
    amxc_llist_iterate(it, (&children)) {
        amxp_proc_info_t* pi = amxc_container_of(it, amxp_proc_info_t, it);
        amxc_var_add(int32_t, &proc->child_proc_pids, pi->pid);
    }
 
leave:
    amxc_llist_clean(&children, amxp_proci_free_it);
    return retval;
}
 
int amxp_proc_ctrl_new(amxp_proc_ctrl_t** proc, amxp_proc_ctrl_cmd_t cmd_build_fn) {
    int retval = -1;
    when_null(proc, leave);
    when_null(cmd_build_fn, leave);
 
    *proc = (amxp_proc_ctrl_t*) calloc(1, sizeof(amxp_proc_ctrl_t));
    when_null(*proc, leave);
 
    when_failed(amxp_subproc_new(&(*proc)->proc), leave);
    when_failed(amxp_timer_new(&(*proc)->timer, amxp_proc_ctrl_timer_callback, *proc), leave);
    when_failed(amxc_array_init(&(*proc)->cmd, 10), leave);
    when_failed(amxc_var_init(&(*proc)->child_proc_pids), leave);
 
    (*proc)->build = cmd_build_fn;
    amxp_slot_connect((*proc)->proc->sigmngr, "stop", NULL, amxp_proc_ctrl_stopped, *proc);
 
    retval = 0;
 
leave:
    if((retval != 0) &&
       ((proc != NULL) && (*proc != NULL))) {
        amxp_subproc_delete(&(*proc)->proc);
        amxp_timer_delete(&(*proc)->timer);
        amxc_array_clean(&(*proc)->cmd, NULL);
        amxc_var_clean(&(*proc)->child_proc_pids);
        free(*proc);
        *proc = NULL;
    }
    return retval;
}
 
void amxp_proc_ctrl_delete(amxp_proc_ctrl_t** proc) {
    when_null(proc, leave);
    when_null(*proc, leave);
 
    amxp_slot_disconnect((*proc)->proc->sigmngr, "stop", amxp_proc_ctrl_stopped);
 
    amxp_proc_ctrl_stop(*proc);
    amxp_subproc_delete(&(*proc)->proc);
    amxp_timer_delete(&(*proc)->timer);
    amxc_array_clean(&(*proc)->cmd, amxp_proc_ctrl_free_char);
    amxc_var_clean(&(*proc)->child_proc_pids);
 
    free(*proc);
    *proc = NULL;
 
leave:
    return;
}
 
int amxp_proc_ctrl_start(amxp_proc_ctrl_t* proc, uint32_t minutes, amxc_var_t* settings) {
    int retval = -1;
    when_null(proc, leave);
 
    amxc_array_clean(&proc->cmd, amxp_proc_ctrl_free_char);
    retval = proc->build(&proc->cmd, settings);
    when_failed(retval, leave);
    when_true(amxc_array_is_empty(&proc->cmd), leave);
 
    retval = amxp_subproc_astart(proc->proc, &proc->cmd);
    when_failed(retval, leave);
 
    if(minutes != 0) {
        amxp_timer_start(proc->timer, minutes * 60 * 1000);
    }
 
    retval = 0;
 
leave:
    return retval;
}
 
int amxp_proc_ctrl_stop(amxp_proc_ctrl_t* proc) {
    int retval = -1;
    when_null(proc, leave);
 
    amxp_timer_stop(proc->timer);
 
    amxp_proc_ctrl_get_child_pids(proc);
    amxp_proc_ctrl_stop_childs(proc);
 
    amxp_subproc_kill(proc->proc, SIGTERM);
    retval = amxp_subproc_wait(proc->proc, 2000);
    if(retval == 1) {
        // not stopped after waiting for 2 seconds
        // forcekill
        amxp_subproc_kill(proc->proc, SIGKILL);
        retval = amxp_subproc_wait(proc->proc, 2000);
    }
 
leave:
    return retval;
}
 
void amxp_proc_ctrl_set_active_duration(amxp_proc_ctrl_t* proc, uint32_t minutes) {
    when_null(proc, leave);
 
    if(minutes == 0) {
        amxp_timer_stop(proc->timer);
    } else {
        if(amxp_subproc_is_running(proc->proc)) {
            // reset timer to new duration time
            amxp_timer_start(proc->timer, minutes * 60 * 1000);
        }
    }
 
leave:
    return;
}
 
void amxp_proc_ctrl_stop_childs(amxp_proc_ctrl_t* proc) {
    when_null(proc, leave);
 
    if(amxc_var_type_of(&proc->child_proc_pids) == AMXC_VAR_ID_LIST) {
        amxc_var_for_each(child_pid, (&proc->child_proc_pids)) {
            pid_t pid = amxc_var_dyncast(uint32_t, child_pid);
            kill(pid, SIGTERM);
        }
    }
 
leave:
    return;
}
 
int amxp_proc_ctrl_get_child_pids(amxp_proc_ctrl_t* proc) {
    int retval = -1;
    when_null(proc, leave);
 
    when_false(amxp_subproc_is_running(proc->proc), leave);
    retval = amxp_proc_ctrl_get_child_pids_proc_children(proc);
    if(retval == 0) {
        goto leave;
    }
 
    retval = amxp_proc_ctrl_get_child_pids_scan_proc(proc);
 
leave:
    if(retval == 0) {
        const amxc_llist_t* list = amxc_var_constcast(amxc_llist_t, &proc->child_proc_pids);
        retval = amxc_llist_size(list);
    }
    return retval;
}