/**
* Copyright © 2015, 2016 Mattias Andrée <maandree@member.fsf.org>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include "common.h"
#include "parse_time.h"
COMMAND("sat")
USAGE("TIME COMMAND...")
/**
* Return the number of bytes required to store a string array.
*
* @param array The string array.
* @return The number of bytes required to store the array.
*/
#ifdef __GNUC__
__attribute__((__pure__))
#endif
static size_t
measure_array(char *array[])
{
size_t rc = 0;
while (*array) rc += strlen(*array++) + 1;
return rc * sizeof(char);
}
/**
* Store a string array.
*
* @param storage The buffer where the array is to be stored.
* @param array The array to store.
* @return Where in the buffer the array ends.
*/
static char *
store_array(char *restrict storage, char *array[])
{
for (; *array; array++, storage++)
storage = stpcpy(storage, *array);
return storage;
}
/**
* Construct the job specifications, as a storable unit.
*
* @param argc `argc` from `main`, see `main` for descriptor.
* @param argv `argv` from `main`, see `main` for descriptor.
* @param envp `envp` from `main`, see `main` for descriptor.
* @return The job (sans serial number) on success, `NULL` on error.
*/
static struct job *
construct_job(int argc, char *argv[], char *envp[])
{
#define E(CASE, DESC) case CASE: fprintf(stderr, "%s: %s: %s\n", argv0, DESC, argv[1]), exit(2)
char *dummy = NULL;
char *timearg;
void *new;
size_t size = 64;
struct job job = { .no = 0 };
struct job *job_full = NULL;
int saved_errno;
timearg = argv[1];
job.argc = argc -= 2, argv += 2;
/* Parse the time argument. */
if (parse_time(timearg, &(job.ts), &(job.clk))) {
switch (errno) {
E (EINVAL, "time parameter cound not be parsed, perhaps you need an external parser");
E (ERANGE, "the specified time is beyond the limit of what can be stored");
E (EDOM, "the specified time is in past, and more than a day ago");
default: goto fail;
}
}
retry:
/* Get the size of the current working directory's pathname. */
t (!(new = realloc(dummy, size <<= 1)));
if (!getcwd(dummy = new, size)) {
t (errno != ERANGE);
goto retry;
}
size = strlen(getcwd(dummy, size)) + 1;
/* Construct full specification. */
job.n = measure_array(argv) + size + measure_array(envp);
t (!(job_full = malloc(sizeof(job) + job.n)));
memcpy(job_full, &job, sizeof(job));
store_array(getcwd(store_array(job_full->payload, argv), size) + size, envp);
fail:
return S(free(dummy)), job_full;
}
/**
* Queue a job for later execution.
*
* @param argc You guess!
* @param argv The first element should be the name of the process,
* the second argument should be the POSIX time (seconds
* since Epoch (1970-01-01 00:00:00 UTC), disregarding
* leap seconds) the job shall be executed. The rest of
* the arguments (being at least one) shoul be the
* command line arguments for the job the run.
* @param envp The environment.
* @return 0 The process was successful.
* @return 1 The process failed queuing the job.
* @return 2 User error, you do not know what you are doing.
* @return 3 satd(1) failed to queue the job.
*/
int
main(int argc, char *argv[], char *envp[])
{
#define WRITE(MSG, N, OFF) t (pwriten(STATE_FILENO, MSG, (size_t)(N), (size_t)(OFF)) < (ssize_t)(N))
struct job *job = NULL;
struct stat attr;
ssize_t r;
PROLOGUE((argc > 2) && (argv[1][0] != '-'), O_RDWR);
t (set_hookpath());
t (!(job = construct_job(argc, argv, envp)));
/* Update state file and run hook. */
t (flock(STATE_FILENO, LOCK_EX));
t (fstat(STATE_FILENO, &attr));
t (r = preadn(STATE_FILENO, &(job->no), sizeof(job->no), (size_t)0), r < 0);
if (r < (ssize_t)sizeof(job->no)) job->no = 0;
else job->no += 1;
WRITE(&(job->no), sizeof(job->no), (size_t)0);
if (attr.st_size < (off_t)sizeof(job->no))
attr.st_size = (off_t)sizeof(job->no);
WRITE(job, sizeof(*job) + job->n, (size_t)(attr.st_size));
fsync(STATE_FILENO);
run_job_or_hook(job, "queued");
t (flock(STATE_FILENO, LOCK_UN));
t (poke_daemon(1, argv0));
CLEANUP_START;
free(job);
CLEANUP_END;
}
