/*

    Task Spooler - a task queue system for the unix user

    Copyright (C) 2007  Lluís Batlle i Rossell

    Please find the license in the provided COPYING file.

*/

#include <signal.h>

#include <string.h>

#include <sys/types.h>

#include <sys/wait.h>

#include <stdlib.h>

#include <unistd.h>

#include <stdio.h>

#include <sys/stat.h>

#include <fcntl.h>

#include "main.h"

/* Returns the write pipe */

static int run_sendmail(const char *dest)

{

    int pid;

    int p[2];

    pipe(p);

    pid = fork();

    switch(pid)

    {

        case 0: /* Child */

            restore_sigmask();

            close(0);

            close(1);

            close(2);

            dup2(p[0], 0);

            execl("/usr/sbin/sendmail", "sendmail", "-oi", dest, NULL);

            error("run sendmail");

        case -1:

            error("fork sendmail");

        default: /* Parent */

            ;

    }

    return p[1];

}

static void write_header(int fd, const char *dest, const char * command,

        int jobid, int errorlevel)

{

    FILE *f;

    f = fdopen(fd, "a");

    if (f == NULL)

        error("Cannot fdopen the letter file");

    fprintf(f, "From: Task Spooler <taskspooler>\n");

    fprintf(f, "To: %s\n", dest);

    fprintf(f, "Subject: the task %i finished with error %i. \n", jobid,

            errorlevel);

    fprintf(f, "\nCommand: %s\n", command);

    fprintf(f, "Output:\n");

    fflush(f);

}

static void copy_output(int write_fd, const char *ofname)

{

    int file_fd;

    char buffer[1000];

    int read_bytes;

    int res;

    file_fd = open(ofname, O_RDONLY);

    if (file_fd == -1)

        error("mail: Cannot open the output file %s", ofname);

    do {

        read_bytes = read(file_fd, buffer, 1000);

        if (read_bytes > 0)

        {

            res = write(write_fd, buffer, read_bytes);

            if (res == -1)

                warning("Cannot write to the mail pipe %i", write_fd);

        }

    } while (read_bytes > 0);

    if (read_bytes == -1)

        warning("Cannot read the output file %s from %i", ofname, file_fd);

}

void hook_on_finish(int jobid, int errorlevel, const char *ofname,

    const char *command)

{

    char *onfinish;

    int pid;

    char sjobid[20];

    char serrorlevel[20];

    int status;

    onfinish = getenv("TS_ONFINISH");

    if (onfinish == NULL)

        return;

    pid = fork();

    switch(pid)

    {

        case 0: /* Child */

            restore_sigmask();

            sprintf(sjobid, "%i", jobid);

            sprintf(serrorlevel, "%i", errorlevel);

            execlp(onfinish, onfinish, sjobid, serrorlevel, ofname, command,

                    NULL);

        case -1:

            error("fork on finish");

        default: /* Parent */

            wait(&status);

    }

}

void send_mail(int jobid, int errorlevel, const char *ofname,

    const char *command)

{

    char to[101];

    char *user;

    char *env_to;

    int write_fd;

    env_to = getenv("TS_MAILTO");

    if (env_to == NULL || strlen(env_to) > 100)

    {

        user = getenv("USER");

        if (user == NULL)

            user = "nobody";

        strcpy(to, user);

        /*strcat(to, "@localhost");*/

    } else

        strcpy(to, env_to);

    write_fd = run_sendmail(to);

    write_header(write_fd, to, command, jobid, errorlevel);

    copy_output(write_fd, ofname);

    close(write_fd);

}