get_memory_usage

gistfile1.txt

void get_memory_usage(char *memsiz){
    pid_t pid = getpid();
    FILE *fh = popen("ps aux", "r");
    char buffer[BUFSIZ];
    char colbuf[BUFSIZ];
    if ( fh == NULL ) {
        perror("popen");
        exit(1);
    } else {
        while ( fgets(buffer, BUFSIZ, fh) != NULL ) {
            unsigned int i = 0, j = 0;
            bool in_space = false;
            bool is_target_pid_line = false;
            unsigned int colnum = 0;
            memset(colbuf, '\0', BUFSIZ);
            while ( buffer[i] != '\0' ) {
                if ( buffer[i] == ' ' or buffer[i] == '\t' ) {
                    in_space = true;
                } else {
                    if ( in_space ) {
                        if ( colnum == 1 ) {
                            // match pid.
                            if ( pid == atoi(colbuf) ) {
                                is_target_pid_line = true;
                            }
                        }
                        if ( is_target_pid_line ) {
                            // It's target Rss size.
                            if ( colnum == 5 ) {
                                int k = 0;
                                while ( colbuf[k] != '\0' ) {
                                    memsiz[k] = colbuf[k];
                                    k++;
                                }
                                pclose(fh);
                                return;
                            }
                        }
                        colnum++;
                        j = 0;
                        memset(colbuf, '\0', BUFSIZ);
                        in_space = false;
                    }
                    colbuf[j] = buffer[i];
                    j++;
                }
                
                i++;
            }   
        }   
    }   
    pclose(fh);
}