diff options
Diffstat (limited to 'server/providers/child_common.c')
| -rw-r--r-- | server/providers/child_common.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/server/providers/child_common.c b/server/providers/child_common.c new file mode 100644 index 000000000..9ec09f297 --- /dev/null +++ b/server/providers/child_common.c @@ -0,0 +1,195 @@ +/* + SSSD + + Common helper functions to be used in child processes + + Authors: + Sumit Bose <sbose@redhat.com> + + Copyright (C) 2009 Red Hat + + This program 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 3 of the License, or + (at your option) any later version. + + This program 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 this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +#include <sys/types.h> +#include <fcntl.h> +#include <tevent.h> +#include <sys/wait.h> + +#include "util/util.h" +#include "util/find_uid.h" +#include "db/sysdb.h" +#include "providers/child_common.h" + +uint8_t *copy_buffer_and_add_zero(TALLOC_CTX *mem_ctx, + const uint8_t *src, size_t len) +{ + uint8_t *str; + + str = talloc_size(mem_ctx, len + 1); + if (str == NULL) { + DEBUG(1, ("talloc_size failed.\n")); + return NULL; + } + memcpy(str, src, len); + str[len] = '\0'; + + return str; +} + +/* Async communication with the child process via a pipe */ + +struct read_pipe_state { + int fd; + uint8_t *buf; + size_t len; +}; + +static void read_pipe_done(struct tevent_context *ev, + struct tevent_fd *fde, + uint16_t flags, void *pvt); + +struct tevent_req *read_pipe_send(TALLOC_CTX *mem_ctx, + struct tevent_context *ev, int fd) +{ + struct tevent_req *req; + struct read_pipe_state *state; + struct tevent_fd *fde; + + req = tevent_req_create(mem_ctx, &state, struct read_pipe_state); + if (req == NULL) return NULL; + + state->fd = fd; + state->buf = talloc_array(state, uint8_t, MAX_CHILD_MSG_SIZE); + state->len = 0; + if (state->buf == NULL) goto fail; + + fde = tevent_add_fd(ev, state, fd, TEVENT_FD_READ, + read_pipe_done, req); + if (fde == NULL) { + DEBUG(1, ("tevent_add_fd failed.\n")); + goto fail; + } + + return req; + +fail: + talloc_zfree(req); + return NULL; +} + +static void read_pipe_done(struct tevent_context *ev, + struct tevent_fd *fde, + uint16_t flags, void *pvt) +{ + ssize_t size; + struct tevent_req *req = talloc_get_type(pvt, struct tevent_req); + struct read_pipe_state *state = tevent_req_data(req, struct read_pipe_state); + + if (flags & TEVENT_FD_WRITE) { + DEBUG(1, ("read_pipe_done called with TEVENT_FD_WRITE, this should not happen.\n")); + tevent_req_error(req, EINVAL); + return; + } + + size = read(state->fd, state->buf + state->len, talloc_get_size(state->buf) - state->len); + if (size == -1) { + if (errno == EAGAIN || errno == EINTR) return; + DEBUG(1, ("read failed [%d][%s].\n", errno, strerror(errno))); + tevent_req_error(req, errno); + return; + } else if (size > 0) { + state->len += size; + if (state->len > talloc_get_size(state->buf)) { + DEBUG(1, ("read to much, this should never happen.\n")); + tevent_req_error(req, EINVAL); + return; + } + return; + } else if (size == 0) { + tevent_req_done(req); + return; + } else { + DEBUG(1, ("unexpected return value of read [%d].\n", size)); + tevent_req_error(req, EINVAL); + return; + } +} + +int read_pipe_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx, + uint8_t **buf, ssize_t *len) +{ + struct read_pipe_state *state = tevent_req_data(req, + struct read_pipe_state); + + TEVENT_REQ_RETURN_ON_ERROR(req); + + *buf = talloc_move(mem_ctx, &state->buf); + *len = state->len; + + return EOK; +} + +/* The pipes to communicate with the child must be nonblocking */ +void fd_nonblocking(int fd) +{ + int flags; + int ret; + + flags = fcntl(fd, F_GETFL, 0); + if (flags == -1) { + ret = errno; + DEBUG(1, ("F_GETFL failed [%d][%s].\n", ret, strerror(ret))); + return; + } + + if (fcntl(fd, F_SETFL, flags | O_NONBLOCK) == -1) { + ret = errno; + DEBUG(1, ("F_SETFL failed [%d][%s].\n", ret, strerror(ret))); + } + + return; +} + +void child_sig_handler(struct tevent_context *ev, + struct tevent_signal *sige, int signum, + int count, void *__siginfo, void *pvt) +{ + int ret; + int child_status; + + DEBUG(7, ("Waiting for [%d] childeren.\n", count)); + do { + errno = 0; + ret = waitpid(-1, &child_status, WNOHANG); + + if (ret == -1) { + DEBUG(1, ("waitpid failed [%d][%s].\n", errno, strerror(errno))); + } else if (ret == 0) { + DEBUG(1, ("waitpid did not found a child with changed status.\n")); + } else { + if (WEXITSTATUS(child_status) != 0) { + DEBUG(1, ("child [%d] failed with status [%d].\n", ret, + child_status)); + } else { + DEBUG(4, ("child [%d] finished successful.\n", ret)); + } + } + + --count; + } while (count < 0); + + return; +} + |