+++ /dev/null
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-/***
- This file is part of systemd.
-
- Copyright 2013 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <stdio.h>
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <sys/mman.h>
-#include <sys/prctl.h>
-
-#include "util.h"
-#include "bus-label.h"
-#include "missing.h"
-
-#include "sd-memfd.h"
-#include "sd-bus.h"
-
-struct sd_memfd {
- int fd;
- FILE *f;
-};
-
-_public_ int sd_memfd_new(sd_memfd **m, const char *name) {
-
- _cleanup_close_ int kdbus = -1;
- _cleanup_free_ char *g = NULL;
- sd_memfd *n;
-
- assert_return(m, -EINVAL);
-
- kdbus = open("/dev/kdbus/control", O_RDWR|O_NOCTTY|O_CLOEXEC);
- if (kdbus < 0)
- return -errno;
-
- if (name) {
- /* The kernel side is pretty picky about the character
- * set here, let's do the usual bus escaping to deal
- * with that. */
-
- g = bus_label_escape(name);
- if (!g)
- return -ENOMEM;
-
- name = g;
-
- } else {
- char pr[17] = {};
-
- /* If no name is specified we generate one. We include
- * a hint indicating our library implementation, and
- * add the thread name to it */
-
- assert_se(prctl(PR_GET_NAME, (unsigned long) pr) >= 0);
-
- if (isempty(pr))
- name = "sd";
- else {
- _cleanup_free_ char *e = NULL;
-
- e = bus_label_escape(pr);
- if (!e)
- return -ENOMEM;
-
- g = strappend("sd-", e);
- if (!g)
- return -ENOMEM;
-
- name = g;
- }
- }
-
- n = new0(struct sd_memfd, 1);
- if (!n)
- return -ENOMEM;
-
- n->fd = memfd_create(name, 0, MFD_ALLOW_SEALING);
- if (n->fd < 0) {
- free(n);
- return -errno;
- }
-
- *m = n;
- return 0;
-}
-
-_public_ int sd_memfd_new_from_fd(sd_memfd **m, int fd) {
- sd_memfd *n;
-
- assert_return(m, -EINVAL);
- assert_return(fd >= 0, -EINVAL);
-
- /* Check if this is a sealable fd */
- if (fcntl(fd, F_GET_SEALS) < 0)
- return -ENOTTY;
-
- n = new0(struct sd_memfd, 1);
- if (!n)
- return -ENOMEM;
-
- n->fd = fd;
- *m = n;
-
- return 0;
-}
-
-_public_ void sd_memfd_free(sd_memfd *m) {
- if (!m)
- return;
-
- if (m->f)
- fclose(m->f);
- else
- safe_close(m->fd);
-
- free(m);
-}
-
-_public_ int sd_memfd_get_fd(sd_memfd *m) {
- assert_return(m, -EINVAL);
-
- return m->fd;
-}
-
-_public_ int sd_memfd_get_file(sd_memfd *m, FILE **f) {
- assert_return(m, -EINVAL);
- assert_return(f, -EINVAL);
-
- if (!m->f) {
- m->f = fdopen(m->fd, "r+");
- if (!m->f)
- return -errno;
- }
-
- *f = m->f;
- return 0;
-}
-
-_public_ int sd_memfd_dup_fd(sd_memfd *m) {
- int fd;
-
- assert_return(m, -EINVAL);
-
- fd = fcntl(m->fd, F_DUPFD_CLOEXEC, 3);
- if (fd < 0)
- return -errno;
-
- return fd;
-}
-
-_public_ int sd_memfd_map(sd_memfd *m, uint64_t offset, size_t size, void **p) {
- void *q;
- int sealed;
-
- assert_return(m, -EINVAL);
- assert_return(size > 0, -EINVAL);
- assert_return(p, -EINVAL);
-
- sealed = sd_memfd_get_sealed(m);
- if (sealed < 0)
- return sealed;
-
- q = mmap(NULL, size, sealed ? PROT_READ : PROT_READ|PROT_WRITE, MAP_PRIVATE, m->fd, offset);
- if (q == MAP_FAILED)
- return -errno;
-
- *p = q;
- return 0;
-}
-
-_public_ int sd_memfd_set_sealed(sd_memfd *m) {
- int r;
-
- assert_return(m, -EINVAL);
-
- r = fcntl(m->fd, F_ADD_SEALS, F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE);
- if (r < 0)
- return -errno;
-
- return 0;
-}
-
-_public_ int sd_memfd_get_sealed(sd_memfd *m) {
- int r;
-
- assert_return(m, -EINVAL);
-
- r = fcntl(m->fd, F_GET_SEALS);
- if (r < 0)
- return -errno;
-
- return (r & (F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE)) ==
- (F_SEAL_SHRINK | F_SEAL_GROW | F_SEAL_WRITE);
-}
-
-_public_ int sd_memfd_get_size(sd_memfd *m, uint64_t *sz) {
- int r;
- struct stat stat;
-
- assert_return(m, -EINVAL);
- assert_return(sz, -EINVAL);
-
- r = fstat(m->fd, &stat);
- if (r < 0)
- return -errno;
-
- *sz = stat.st_size;
- return r;
-}
-
-_public_ int sd_memfd_set_size(sd_memfd *m, uint64_t sz) {
- int r;
-
- assert_return(m, -EINVAL);
-
- r = ftruncate(m->fd, sz);
- if (r < 0)
- return -errno;
-
- return r;
-}
-
-_public_ int sd_memfd_new_and_map(sd_memfd **m, const char *name, size_t sz, void **p) {
- sd_memfd *n;
- int r;
-
- r = sd_memfd_new(&n, name);
- if (r < 0)
- return r;
-
- r = sd_memfd_set_size(n, sz);
- if (r < 0) {
- sd_memfd_free(n);
- return r;
- }
-
- r = sd_memfd_map(n, 0, sz, p);
- if (r < 0) {
- sd_memfd_free(n);
- return r;
- }
-
- *m = n;
- return 0;
-}
-
-_public_ int sd_memfd_get_name(sd_memfd *m, char **name) {
- char path[sizeof("/proc/self/fd/") + DECIMAL_STR_MAX(int)], buf[FILENAME_MAX+1], *e;
- const char *delim, *end;
- _cleanup_free_ char *n = NULL;
- ssize_t k;
-
- assert_return(m, -EINVAL);
- assert_return(name, -EINVAL);
-
- sprintf(path, "/proc/self/fd/%i", m->fd);
-
- k = readlink(path, buf, sizeof(buf));
- if (k < 0)
- return -errno;
-
- if ((size_t) k >= sizeof(buf))
- return -E2BIG;
-
- buf[k] = 0;
-
- delim = strstr(buf, ":[");
- if (!delim)
- return -EIO;
-
- delim = strchr(delim + 2, ':');
- if (!delim)
- return -EIO;
-
- delim++;
-
- end = strchr(delim, ']');
- if (!end)
- return -EIO;
-
- n = strndup(delim, end - delim);
- if (!n)
- return -ENOMEM;
-
- e = bus_label_unescape(n);
- if (!e)
- return -ENOMEM;
-
- *name = e;
-
- return 0;
-}
~ianmdlvl / elogind.git / blobdiff