diff options
Diffstat (limited to 'src/journal/journal-send.c')
| -rw-r--r-- | src/journal/journal-send.c | 516 |
1 files changed, 516 insertions, 0 deletions
diff --git a/src/journal/journal-send.c b/src/journal/journal-send.c new file mode 100644 index 0000000000..32e94af91f --- /dev/null +++ b/src/journal/journal-send.c @@ -0,0 +1,516 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2011 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 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 + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <sys/socket.h> +#include <sys/un.h> +#include <errno.h> +#include <stddef.h> +#include <unistd.h> +#include <fcntl.h> + +#define SD_JOURNAL_SUPPRESS_LOCATION + +#include "sd-journal.h" +#include "util.h" +#include "socket-util.h" + +#define SNDBUF_SIZE (8*1024*1024) + +/* We open a single fd, and we'll share it with the current process, + * all its threads, and all its subprocesses. This means we need to + * initialize it atomically, and need to operate on it atomically + * never assuming we are the only user */ + +static int journal_fd(void) { + int fd; + static int fd_plus_one = 0; + +retry: + if (fd_plus_one > 0) + return fd_plus_one - 1; + + fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0); + if (fd < 0) + return -errno; + + fd_inc_sndbuf(fd, SNDBUF_SIZE); + + if (!__sync_bool_compare_and_swap(&fd_plus_one, 0, fd+1)) { + close_nointr_nofail(fd); + goto retry; + } + + return fd; +} + +_public_ int sd_journal_print(int priority, const char *format, ...) { + int r; + va_list ap; + + va_start(ap, format); + r = sd_journal_printv(priority, format, ap); + va_end(ap); + + return r; +} + +_public_ int sd_journal_printv(int priority, const char *format, va_list ap) { + char buffer[8 + LINE_MAX], p[11]; + struct iovec iov[2]; + + if (priority < 0 || priority > 7) + return -EINVAL; + + if (!format) + return -EINVAL; + + snprintf(p, sizeof(p), "PRIORITY=%i", priority & LOG_PRIMASK); + char_array_0(p); + + memcpy(buffer, "MESSAGE=", 8); + vsnprintf(buffer+8, sizeof(buffer) - 8, format, ap); + char_array_0(buffer); + + zero(iov); + IOVEC_SET_STRING(iov[0], buffer); + IOVEC_SET_STRING(iov[1], p); + + return sd_journal_sendv(iov, 2); +} + +static int fill_iovec_sprintf(const char *format, va_list ap, int extra, struct iovec **_iov) { + int r, n = 0, i, j; + struct iovec *iov = NULL; + int saved_errno; + + assert(_iov); + saved_errno = errno; + + if (extra > 0) { + n = MAX(extra * 2, extra + 4); + iov = malloc0(n * sizeof(struct iovec)); + if (!iov) { + r = -ENOMEM; + goto fail; + } + + i = extra; + } else + i = 0; + + while (format) { + struct iovec *c; + char *buffer; + + if (i >= n) { + n = MAX(i*2, 4); + c = realloc(iov, n * sizeof(struct iovec)); + if (!c) { + r = -ENOMEM; + goto fail; + } + + iov = c; + } + + if (vasprintf(&buffer, format, ap) < 0) { + r = -ENOMEM; + goto fail; + } + + IOVEC_SET_STRING(iov[i++], buffer); + + format = va_arg(ap, char *); + } + + *_iov = iov; + + errno = saved_errno; + return i; + +fail: + for (j = 0; j < i; j++) + free(iov[j].iov_base); + + free(iov); + + errno = saved_errno; + return r; +} + +_public_ int sd_journal_send(const char *format, ...) { + int r, i, j; + va_list ap; + struct iovec *iov = NULL; + + va_start(ap, format); + i = fill_iovec_sprintf(format, ap, 0, &iov); + va_end(ap); + + if (_unlikely_(i < 0)) { + r = i; + goto finish; + } + + r = sd_journal_sendv(iov, i); + +finish: + for (j = 0; j < i; j++) + free(iov[j].iov_base); + + free(iov); + + return r; +} + +_public_ int sd_journal_sendv(const struct iovec *iov, int n) { + int fd, buffer_fd; + struct iovec *w; + uint64_t *l; + int r, i, j = 0; + struct msghdr mh; + struct sockaddr_un sa; + ssize_t k; + int saved_errno; + union { + struct cmsghdr cmsghdr; + uint8_t buf[CMSG_SPACE(sizeof(int))]; + } control; + struct cmsghdr *cmsg; + /* We use /dev/shm instead of /tmp here, since we want this to + * be a tmpfs, and one that is available from early boot on + * and where unprivileged users can create files. */ + char path[] = "/dev/shm/journal.XXXXXX"; + + if (_unlikely_(!iov)) + return -EINVAL; + + if (_unlikely_(n <= 0)) + return -EINVAL; + + saved_errno = errno; + + w = alloca(sizeof(struct iovec) * n * 5); + l = alloca(sizeof(uint64_t) * n); + + for (i = 0; i < n; i++) { + char *c, *nl; + + if (_unlikely_(!iov[i].iov_base || iov[i].iov_len <= 1)) { + r = -EINVAL; + goto finish; + } + + c = memchr(iov[i].iov_base, '=', iov[i].iov_len); + if (_unlikely_(!c || c == iov[i].iov_base)) { + r = -EINVAL; + goto finish; + } + + nl = memchr(iov[i].iov_base, '\n', iov[i].iov_len); + if (nl) { + if (_unlikely_(nl < c)) { + r = -EINVAL; + goto finish; + } + + /* Already includes a newline? Bummer, then + * let's write the variable name, then a + * newline, then the size (64bit LE), followed + * by the data and a final newline */ + + w[j].iov_base = iov[i].iov_base; + w[j].iov_len = c - (char*) iov[i].iov_base; + j++; + + IOVEC_SET_STRING(w[j++], "\n"); + + l[i] = htole64(iov[i].iov_len - (c - (char*) iov[i].iov_base) - 1); + w[j].iov_base = &l[i]; + w[j].iov_len = sizeof(uint64_t); + j++; + + w[j].iov_base = c + 1; + w[j].iov_len = iov[i].iov_len - (c - (char*) iov[i].iov_base) - 1; + j++; + + } else + /* Nothing special? Then just add the line and + * append a newline */ + w[j++] = iov[i]; + + IOVEC_SET_STRING(w[j++], "\n"); + } + + fd = journal_fd(); + if (_unlikely_(fd < 0)) { + r = fd; + goto finish; + } + + zero(sa); + sa.sun_family = AF_UNIX; + strncpy(sa.sun_path, "/run/systemd/journal/socket", sizeof(sa.sun_path)); + + zero(mh); + mh.msg_name = &sa; + mh.msg_namelen = offsetof(struct sockaddr_un, sun_path) + strlen(sa.sun_path); + mh.msg_iov = w; + mh.msg_iovlen = j; + + k = sendmsg(fd, &mh, MSG_NOSIGNAL); + if (k >= 0) { + r = 0; + goto finish; + } + + if (errno != EMSGSIZE && errno != ENOBUFS) { + r = -errno; + goto finish; + } + + /* Message doesn't fit... Let's dump the data in a temporary + * file and just pass a file descriptor of it to the other + * side */ + + buffer_fd = mkostemp(path, O_CLOEXEC|O_RDWR); + if (buffer_fd < 0) { + r = -errno; + goto finish; + } + + if (unlink(path) < 0) { + close_nointr_nofail(buffer_fd); + r = -errno; + goto finish; + } + + n = writev(buffer_fd, w, j); + if (n < 0) { + close_nointr_nofail(buffer_fd); + r = -errno; + goto finish; + } + + mh.msg_iov = NULL; + mh.msg_iovlen = 0; + + zero(control); + mh.msg_control = &control; + mh.msg_controllen = sizeof(control); + + cmsg = CMSG_FIRSTHDR(&mh); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + cmsg->cmsg_len = CMSG_LEN(sizeof(int)); + memcpy(CMSG_DATA(cmsg), &buffer_fd, sizeof(int)); + + mh.msg_controllen = cmsg->cmsg_len; + + k = sendmsg(fd, &mh, MSG_NOSIGNAL); + close_nointr_nofail(buffer_fd); + + if (k < 0) { + r = -errno; + goto finish; + } + + r = 0; + +finish: + errno = saved_errno; + + return r; +} + +_public_ int sd_journal_stream_fd(const char *identifier, int priority, int level_prefix) { + union sockaddr_union sa; + int fd; + char *header; + size_t l; + ssize_t r; + + if (priority < 0 || priority > 7) + return -EINVAL; + + fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0); + if (fd < 0) + return -errno; + + zero(sa); + sa.un.sun_family = AF_UNIX; + strncpy(sa.un.sun_path, "/run/systemd/journal/stdout", sizeof(sa.un.sun_path)); + + r = connect(fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path)); + if (r < 0) { + close_nointr_nofail(fd); + return -errno; + } + + if (shutdown(fd, SHUT_RD) < 0) { + close_nointr_nofail(fd); + return -errno; + } + + fd_inc_sndbuf(fd, SNDBUF_SIZE); + + if (!identifier) + identifier = ""; + + l = strlen(identifier); + header = alloca(l + 1 + 2 + 2 + 2 + 2 + 2); + + memcpy(header, identifier, l); + header[l++] = '\n'; + header[l++] = '0' + priority; + header[l++] = '\n'; + header[l++] = '0' + !!level_prefix; + header[l++] = '\n'; + header[l++] = '0'; + header[l++] = '\n'; + header[l++] = '0'; + header[l++] = '\n'; + header[l++] = '0'; + header[l++] = '\n'; + + r = loop_write(fd, header, l, false); + if (r < 0) { + close_nointr_nofail(fd); + return (int) r; + } + + if ((size_t) r != l) { + close_nointr_nofail(fd); + return -errno; + } + + return fd; +} + +_public_ int sd_journal_print_with_location(int priority, const char *file, const char *line, const char *func, const char *format, ...) { + int r; + va_list ap; + + va_start(ap, format); + r = sd_journal_printv_with_location(priority, file, line, func, format, ap); + va_end(ap); + + return r; +} + +_public_ int sd_journal_printv_with_location(int priority, const char *file, const char *line, const char *func, const char *format, va_list ap) { + char buffer[8 + LINE_MAX], p[11]; + struct iovec iov[5]; + char *f; + size_t fl; + + if (priority < 0 || priority > 7) + return -EINVAL; + + if (_unlikely_(!format)) + return -EINVAL; + + snprintf(p, sizeof(p), "PRIORITY=%i", priority & LOG_PRIMASK); + char_array_0(p); + + memcpy(buffer, "MESSAGE=", 8); + vsnprintf(buffer+8, sizeof(buffer) - 8, format, ap); + char_array_0(buffer); + + /* func is initialized from __func__ which is not a macro, but + * a static const char[], hence cannot easily be prefixed with + * CODE_FUNC=, hence let's do it manually here. */ + fl = strlen(func); + f = alloca(fl + 10); + memcpy(f, "CODE_FUNC=", 10); + memcpy(f + 10, func, fl + 1); + + zero(iov); + IOVEC_SET_STRING(iov[0], buffer); + IOVEC_SET_STRING(iov[1], p); + IOVEC_SET_STRING(iov[2], file); + IOVEC_SET_STRING(iov[3], line); + IOVEC_SET_STRING(iov[4], f); + + return sd_journal_sendv(iov, ELEMENTSOF(iov)); +} + +_public_ int sd_journal_send_with_location(const char *file, const char *line, const char *func, const char *format, ...) { + int r, i, j; + va_list ap; + struct iovec *iov = NULL; + char *f; + size_t fl; + + va_start(ap, format); + i = fill_iovec_sprintf(format, ap, 3, &iov); + va_end(ap); + + if (_unlikely_(i < 0)) { + r = i; + goto finish; + } + + fl = strlen(func); + f = alloca(fl + 10); + memcpy(f, "CODE_FUNC=", 10); + memcpy(f + 10, func, fl + 1); + + IOVEC_SET_STRING(iov[0], file); + IOVEC_SET_STRING(iov[1], line); + IOVEC_SET_STRING(iov[2], f); + + r = sd_journal_sendv(iov, i); + +finish: + for (j = 3; j < i; j++) + free(iov[j].iov_base); + + free(iov); + + return r; +} + +_public_ int sd_journal_sendv_with_location(const char *file, const char *line, const char *func, const struct iovec *iov, int n) { + struct iovec *niov; + char *f; + size_t fl; + + if (_unlikely_(!iov)) + return -EINVAL; + + if (_unlikely_(n <= 0)) + return -EINVAL; + + niov = alloca(sizeof(struct iovec) * (n + 3)); + memcpy(niov, iov, sizeof(struct iovec) * n); + + fl = strlen(func); + f = alloca(fl + 10); + memcpy(f, "CODE_FUNC=", 10); + memcpy(f + 10, func, fl + 1); + + IOVEC_SET_STRING(niov[n++], file); + IOVEC_SET_STRING(niov[n++], line); + IOVEC_SET_STRING(niov[n++], f); + + return sd_journal_sendv(niov, n); +} |