amxp_proc_info.c

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#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
 
#include <sys/resource.h>
 
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <limits.h>
#include <libgen.h>
#include <dirent.h>
#include <ctype.h>
 
#include <amxc/amxc.h>
#include <amxc/amxc_macros.h>
#include <amxp/amxp.h>
 
static amxp_expr_status_t amxp_proci_expr_get_field(UNUSED amxp_expr_t* expr,
                                                    amxc_var_t* value,
                                                    const char* path,
                                                    void* priv) {
    amxp_expr_status_t status = amxp_expr_status_ok;
    amxp_proc_info_t* pi = (amxp_proc_info_t*) priv;
 
    if(strcmp(path, "name") == 0) {
        amxc_var_set(cstring_t, value, pi->name);
    } else if(strcmp(path, "parent_pid") == 0) {
        amxc_var_set(int32_t, value, pi->parent_pid);
    } else if(strcmp(path, "ppid") == 0) {
        amxc_var_set(int32_t, value, pi->parent_pid);
    } else if(strcmp(path, "state") == 0) {
        amxc_var_set(int8_t, value, pi->state);
    } else {
        status = amxp_expr_status_field_not_found;
    }
 
    return status;
}
 
static void amxp_proci_fill(amxp_proc_info_t* proc_info, amxc_var_t* data) {
    int index = 0;
    amxc_var_for_each(item, data) {
        switch(index) {
        case 0:
            proc_info->pid = amxc_var_dyncast(int32_t, item);
            break;
        case 1: {
            amxc_string_t name;
            char* n = amxc_var_take(cstring_t, item);
            amxc_string_init(&name, 0);
            amxc_string_push_buffer(&name, n, n == NULL ? 0 : strlen(n) + 1);
            amxc_string_trim(&name, ispunct);
            proc_info->name = amxc_string_take_buffer(&name);
        }
        break;
        case 2:
            proc_info->state = amxc_var_dyncast(int8_t, item);
            break;
        case 3:
            proc_info->parent_pid = amxc_var_dyncast(int32_t, item);
            break;
        case 4:
            proc_info->process_gid = amxc_var_dyncast(int32_t, item);
            break;
        case 5:
            proc_info->session_id = amxc_var_dyncast(int32_t, item);
            break;
        }
        index++;
    }
}
 
static amxp_proc_info_t* amxp_proci_read_stat(amxc_string_t* file) {
    FILE* fp = NULL;
    amxp_proc_info_t* proc_info = NULL;
    amxc_var_t stat;
    ssize_t read = 0;
    char* line = NULL;
    size_t len = 0;
 
    amxc_var_init(&stat);
 
    fp = fopen(amxc_string_get(file, 0), "r");
    if(fp == NULL) {
        goto exit;
    }
 
    read = getline(&line, &len, fp);
    if(read == -1) {
        fclose(fp);
        free(line);
        goto exit;
    }
    fclose(fp);
 
    amxc_var_push(ssv_string_t, &stat, line);
    amxc_var_cast(&stat, AMXC_VAR_ID_LIST);
 
    proc_info = (amxp_proc_info_t*) calloc(1, sizeof(amxp_proc_info_t));
    when_null(proc_info, exit);
 
    amxp_proci_fill(proc_info, &stat);
 
exit:
    amxc_var_clean(&stat);
    return proc_info;
}
 
static int amxp_proci_scan_proc(amxc_llist_t* procs, amxp_expr_t* expr) {
    int retval = -1;
    DIR* dp;
    struct dirent* ep;
    amxc_string_t filename;
    amxp_proc_info_t* pi = NULL;
    amxp_expr_status_t status = amxp_expr_status_ok;
 
    amxc_string_init(&filename, 128);
 
    dp = opendir("/proc/");
    when_null(dp, exit);
 
    for(ep = readdir(dp); ep; ep = readdir(dp)) {
        if(ep->d_type != DT_DIR) {
            continue;
        }
 
        if(ep->d_name[0] == '.') {
            continue;
        }
 
        amxc_string_reset(&filename);
        amxc_string_setf(&filename, "/proc/%s/stat", ep->d_name);
        pi = amxp_proci_read_stat(&filename);
        if(pi != NULL) {
            if(expr != NULL) {
                if(amxp_expr_evaluate(expr, amxp_proci_expr_get_field, pi, &status)) {
                    amxc_llist_append(procs, &pi->it);
                } else {
                    amxp_proci_free_it(&pi->it);
                }
            } else {
                amxc_llist_append(procs, &pi->it);
            }
        }
 
    }
    closedir(dp);
 
    retval = 0;
 
exit:
    amxc_string_clean(&filename);
    return retval;
}
 
void amxp_proci_free_it(amxc_llist_it_t* it) {
    amxp_proc_info_t* pi = amxc_container_of(it, amxp_proc_info_t, it);
    free(pi->name);
    free(pi);
}
 
int amxp_proci_findf(amxc_llist_t* result, const char* filter, ...) {
    int retval = -1;
    amxc_string_t expression;
    va_list args;
    amxp_expr_t expr;
 
    amxc_string_init(&expression, 0);
    when_null(result, exit);
 
    if(filter != NULL) {
        va_start(args, filter);
        amxc_string_vsetf(&expression, filter, args);
        va_end(args);
        when_failed(amxp_expr_init(&expr, amxc_string_get(&expression, 0)), exit);
    }
 
 
    retval = amxp_proci_scan_proc(result, filter == NULL ? NULL : &expr);
 
exit:
    if(filter != NULL) {
        amxp_expr_clean(&expr);
    }
    amxc_string_clean(&expression);
    return retval;
}