src/lib/lib.c

	lib.c revision 02c335c23bf5fa225a467c19f2c063fb0dc7b8c3
/* Copyright (c) 2001-2016 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "array.h"
#include "env-util.h"
#include "hostpid.h"
#include "ipwd.h"
#include "process-title.h"

#include <unistd.h>
#include <sys/time.h>

struct atexit_callback {
    int priority;
    lib_atexit_callback_t *callback;
};

static ARRAY(struct atexit_callback) atexit_callbacks = ARRAY_INIT;

int close_keep_errno(int *fd)
{
    int ret, old_errno = errno;

    i_assert(*fd != -1);

    ret = close(*fd);
    *fd = -1;
    errno = old_errno;
    return ret;
}

#undef i_unlink
int i_unlink(const char *path, const char *source_fname,
         unsigned int source_linenum)
{
    if (unlink(path) < 0) {
        i_error("unlink(%s) failed: %m (in %s:%u)",
            path, source_fname, source_linenum);
        return -1;
    }
    return 0;
}

#undef i_unlink_if_exists
int i_unlink_if_exists(const char *path, const char *source_fname,
               unsigned int source_linenum)
{
    if (unlink(path) == 0)
        return 1;
    else if (errno == ENOENT)
        return 0;
    else {
        i_error("unlink(%s) failed: %m (in %s:%u)",
            path, source_fname, source_linenum);
        return -1;
    }
}

void i_getopt_reset(void)
{
#ifdef __GLIBC__
    /* a) for subcommands allow -options anywhere in command line
       b) this is actually required for the reset to work (glibc bug?) */
    optind = 0;
#else
    optind = 1;
#endif
}

void lib_atexit(lib_atexit_callback_t *callback)
{
    lib_atexit_priority(callback, 0);
}

void lib_atexit_priority(lib_atexit_callback_t *callback, int priority)
{
    struct atexit_callback *cb;
    const struct atexit_callback *callbacks;
    unsigned int i, count;

    if (!array_is_created(&atexit_callbacks))
        i_array_init(&atexit_callbacks, 8);
    else {
        /* skip if it's already added */
        callbacks = array_get(&atexit_callbacks, &count);
        for (i = count; i > 0; i--) {
            if (callbacks[i-1].callback == callback) {
                i_assert(callbacks[i-1].priority == priority);
                return;
            }
        }
    }
    cb = array_append_space(&atexit_callbacks);
    cb->priority = priority;
    cb->callback = callback;
}

static int atexit_callback_priority_cmp(const struct atexit_callback *cb1,
                    const struct atexit_callback *cb2)
{
    return cb1->priority - cb2->priority;
}

void lib_atexit_run(void)
{
    const struct atexit_callback *cb;

    if (array_is_created(&atexit_callbacks)) {
        array_sort(&atexit_callbacks, atexit_callback_priority_cmp);
        array_foreach(&atexit_callbacks, cb)
            (*cb->callback)();
        array_free(&atexit_callbacks);
    }
}

void lib_init(void)
{
    struct timeval tv;

    /* standard way to get rand() return different values. */
    if (gettimeofday(&tv, NULL) < 0)
        i_fatal("gettimeofday(): %m");
    rand_set_seed((unsigned int) (tv.tv_sec ^ tv.tv_usec ^ getpid()));

    data_stack_init();
    hostpid_init();
}

void lib_deinit(void)
{
    lib_atexit_run();
    ipwd_deinit();
    hostpid_deinit();
    data_stack_deinit();
    env_deinit();
    failures_deinit();
    process_title_deinit();
}