diff options
Diffstat (limited to 'src/mds-server.c')
| -rw-r--r-- | src/mds-server.c | 1597 |
1 files changed, 0 insertions, 1597 deletions
diff --git a/src/mds-server.c b/src/mds-server.c deleted file mode 100644 index d707eab..0000000 --- a/src/mds-server.c +++ /dev/null @@ -1,1597 +0,0 @@ -/** - * mds — A micro-display server - * Copyright © 2014 Mattias Andrée (maandree@member.fsf.org) - * - * 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 "mds-server.h" - -#include <libmdsserver/config.h> -#include <libmdsserver/linked-list.h> -#include <libmdsserver/hash-table.h> -#include <libmdsserver/fd-table.h> -#include <libmdsserver/mds-message.h> -#include <libmdsserver/macros.h> -#include <libmdsserver/util.h> -#include <libmdsserver/hash-help.h> - -#include <alloca.h> -#include <signal.h> -#include <stdio.h> -#include <string.h> -#include <stdlib.h> -#include <limits.h> -#include <unistd.h> -#include <pwd.h> -#include <errno.h> -#include <pthread.h> -#include <sys/socket.h> -#include <sys/mman.h> -#include <fcntl.h> -#include <sys/stat.h> -#include <sys/types.h> -#include <dirent.h> -#include <inttypes.h> - - - -#define MDS_SERVER_VARS_VERSION 0 - - -/** - * Number of elements in `argv` - */ -static int argc; - -/** - * Command line arguments - */ -static char** argv; - - -/** - * The program run state, 1 when running, 0 when shutting down - */ -static volatile sig_atomic_t running = 1; - -/** - * Non-zero when the program is about to re-exec - */ -static volatile sig_atomic_t reexecing = 0; - -/** - * The number of running slaves - */ -static int running_slaves = 0; - -/** - * Mutex for slave data - */ -static pthread_mutex_t slave_mutex; - -/** - * Condition for slave data - */ -static pthread_cond_t slave_cond; - -/** - * The thread that runs the master loop - */ -static pthread_t master_thread; - -/** - * Map from client socket file descriptor to all information (client_t) - */ -static fd_table_t client_map; - -/** - * List of client information (client_t) - */ -static linked_list_t client_list; - -/** - * The next free ID for a client - */ -static uint64_t next_id = 1; - - - -/** - * Entry point of the server - * - * @param argc_ Number of elements in `argv_` - * @param argv_ Command line arguments - * @return Non-zero on error - */ -int main(int argc_, char** argv_) -{ - int is_respawn = -1; - int socket_fd = -1; - int reexec = 0; - int unparsed_args_ptr = 1; - char* unparsed_args[ARGC_LIMIT + LIBEXEC_ARGC_EXTRA_LIMIT + 1]; - int i; - pthread_t _slave_thread; - - - argc = argc_; - argv = argv_; - - - /* Drop privileges like it's hot. */ - if (drop_privileges()) - { - perror(*argv); - return 1; - } - - - /* Sanity check the number of command line arguments. */ - if (argc > ARGC_LIMIT + LIBEXEC_ARGC_EXTRA_LIMIT) - { - eprint("that number of arguments is ridiculous, I will not allow it."); - return 1; - } - - - /* Parse command line arguments. */ - for (i = 1; i < argc; i++) - { - char* arg = argv[i]; - int v; - if ((v = strequals(arg, "--initial-spawn")) || /* Initial spawn? */ - strequals(arg, "--respawn")) /* Respawning after crash? */ - if (is_respawn == v) - { - eprintf("conflicting arguments %s and %s cannot be combined.", - "--initial-spawn", "--respawn"); - return 1; - } - else - is_respawn = !v; - else if (startswith(arg, "--socket-fd=")) /* Socket file descriptor. */ - { - if (socket_fd != -1) - { - eprintf("duplicate declaration of %s.", "--socket-fd"); - return 1; - } - if (strict_atoi(arg += strlen("--socket-fd="), &socket_fd, 0, INT_MAX) < 0) - { - eprintf("invalid value for %s: %s.", "--socket-fd", arg); - return 1; - } - } - else if (strequals(arg, "--re-exec")) /* Re-exec state-marshal. */ - reexec = 1; - else - /* Not recognised, it is probably for another server. */ - unparsed_args[unparsed_args_ptr++] = arg; - } - unparsed_args[unparsed_args_ptr] = NULL; - if (reexec) - is_respawn = 1; - - - /* Check that manditory arguments have been specified. */ - if (is_respawn < 0) - { - eprintf("missing state argument, require either %s or %s.", - "--initial-spawn", "--respawn"); - return 1; - } - if (socket_fd < 0) - { - eprint("missing socket file descriptor argument."); - return 1; - } - - - /* Run mdsinitrc. */ - if (is_respawn == 0) - { - pid_t pid = fork(); - if (pid == (pid_t)-1) - { - perror(*argv); - return 1; - } - if (pid == 0) /* Child process exec:s, the parent continues without waiting for it. */ - { - /* Close all files except stdin, stdout and stderr. */ - close_files((fd > 2) || (fd == socket_fd)); - - /* Run initrc */ - run_initrc(unparsed_args); - return 1; - } - } - - - /* Create list and table of clients. */ - if (reexec == 0) - { - if (fd_table_create(&client_map)) - { - perror(*argv); - fd_table_destroy(&client_map, NULL, NULL); - return 1; - } - if (linked_list_create(&client_list, 32)) - { - perror(*argv); - fd_table_destroy(&client_map, NULL, NULL); - linked_list_destroy(&client_list); - return 1; - } - } - - - /* Store the current thread so it can be killed from elsewhere. */ - master_thread = pthread_self(); - - - /* Make the server update without all slaves dying on SIGUSR1. */ - if (xsigaction(SIGUSR1, sigusr1_trap) < 0) - { - perror(*argv); - fd_table_destroy(&client_map, NULL, NULL); - linked_list_destroy(&client_list); - return 1; - } - - - /* Create mutex and condition for slave counter. */ - pthread_mutex_init(&slave_mutex, NULL); - pthread_cond_init(&slave_cond, NULL); - - - /* Unmarshal the state of the server. */ - if (reexec) - { - pid_t pid = getpid(); - int reexec_fd, r; - char shm_path[NAME_MAX + 1]; - xsnprintf(shm_path, SHM_PATH_PATTERN, (unsigned long int)pid); - reexec_fd = shm_open(shm_path, O_RDWR | O_CREAT | O_EXCL, S_IRWXU); - if (reexec_fd < 0) - { - perror(*argv); - r = -1; - } - else - { - r = unmarshal_server(reexec_fd); - close(reexec_fd); - shm_unlink(shm_path); - } - if (r < 0) - { - /* Close all files (hopefully sockets) we do not know what they are. */ - close_files((fd > 2) && (fd != socket_fd) && (fd_table_contains_key(&client_map, fd) == 0)); - } - } - - /* Accepting incoming connections. */ - while (running && (reexecing == 0)) - { - /* Accept connection. */ - int client_fd = accept(socket_fd, NULL, NULL); - - /* Handle errors and shutdown. */ - if (client_fd == -1) - { - switch (errno) - { - case EINTR: - /* Interrupted. */ - if (reexecing) - goto reexec; - break; - - case ECONNABORTED: - case EINVAL: - /* Closing. */ - running = 0; - break; - - default: - /* Error. */ - perror(*argv); - break; - } - continue; - } - - /* Increase number of running slaves. */ - with_mutex(slave_mutex, running_slaves++;); - - /* Start slave thread. */ - errno = pthread_create(&_slave_thread, NULL, slave_loop, (void*)(intptr_t)client_fd); - if (errno) - { - perror(*argv); - with_mutex(slave_mutex, running_slaves--;); - } - } - if (reexecing) - goto reexec; - - - /* Wait for all slaves to close. */ - with_mutex(slave_mutex, - while (running_slaves > 0) - pthread_cond_wait(&slave_cond, &slave_mutex);); - - - /* Release resources. */ - fd_table_destroy(&client_map, NULL, NULL); - linked_list_destroy(&client_list); - pthread_mutex_destroy(&slave_mutex); - pthread_cond_destroy(&slave_cond); - - return 0; - - - reexec: - { - pid_t pid = getpid(); - int reexec_fd; - char shm_path[NAME_MAX + 1]; - - /* Join with all slaves threads. */ - with_mutex(slave_mutex, - while (running_slaves > 0) - pthread_cond_wait(&slave_cond, &slave_mutex);); - - /* Release resources. */ - pthread_mutex_destroy(&slave_mutex); - pthread_cond_destroy(&slave_cond); - - /* Marshal the state of the server. */ - xsnprintf(shm_path, SHM_PATH_PATTERN, (unsigned long int)pid); - reexec_fd = shm_open(shm_path, O_RDWR | O_CREAT | O_EXCL, S_IRWXU); - if (reexec_fd < 0) - { - perror(*argv); - return 1; - } - if (marshal_server(reexec_fd) < 0) - goto reexec_fail; - close(reexec_fd); - reexec_fd = -1; - - /* Re-exec the server. */ - reexec_server(argc, argv, reexec); - - reexec_fail: - perror(*argv); - if (reexec_fd >= 0) - close(reexec_fd); - shm_unlink(shm_path); - /* Returning non-zero is important, otherwise the server cannot - be respawn if the re-exec fails. */ - return 1; - } -} - - -/** - * Master function for slave threads - * - * @param data Input data - * @return Outout data - */ -void* slave_loop(void* data) -{ - int socket_fd = (int)(intptr_t)data; - ssize_t entry = LINKED_LIST_UNUSED; - size_t information_address = fd_table_get(&client_map, (size_t)socket_fd); - client_t* information = (client_t*)(void*)information_address; - int mutex_created = 0; - char* msgbuf = NULL; - size_t n; - size_t tmp; - int r; - - - if (information == NULL) - { - /* Create information table. */ - if (xmalloc(information, 1, client_t)) - { - perror(*argv); - goto fail; - } - - /* NULL-out pointers. */ - information->interception_conditions = NULL; - information->send_pending = NULL; - - /* Add to list of clients. */ - pthread_mutex_lock(&slave_mutex); - entry = linked_list_insert_end(&client_list, (size_t)(void*)information); - if (entry == LINKED_LIST_UNUSED) - { - perror(*argv); - pthread_mutex_unlock(&slave_mutex); - goto fail; - } - - /* Add client to table. */ - tmp = fd_table_put(&client_map, socket_fd, (size_t)(void*)information); - pthread_mutex_unlock(&slave_mutex); - if ((tmp == 0) && errno) - { - perror(*argv); - goto fail; - } - - /* Fill information table. */ - information->list_entry = entry; - information->socket_fd = socket_fd; - information->open = 1; - information->id = 0; - information->interception_conditions_count = 0; - information->send_pending_size = 0; - if (mds_message_initialise(&(information->message))) - { - perror(*argv); - goto fail; - } - } - - - /* Store the thread so that other threads can kill it. */ - information->thread = pthread_self(); - /* Create mutex to make sure two thread to not try to send - messages concurrently, and other slave local actions. */ - pthread_mutex_init(&(information->mutex), NULL); - mutex_created = 1; - - - /* Make the server update without all slaves dying on SIGUSR1. */ - if (xsigaction(SIGUSR1, sigusr1_trap) < 0) - { - perror(*argv); - goto fail; - } - - - /* Fetch messages from the slave. */ - if (information->open) - while (reexecing == 0) - { - /* Send queued messages. */ - if (information->send_pending_size > 0) - { - char* sendbuf = information->send_pending; - char* sendbuf_ = sendbuf; - size_t sent; - n = information->send_pending_size; - information->send_pending_size = 0; - information->send_pending = NULL; - with_mutex(information->mutex, - while (n > 0) - { - sent = send_message(information->socket_fd, sendbuf_, n); - if ((sent < n) && (errno != EINTR)) /* Ignore EINTR */ - { - perror(*argv); - break; - } - n -= sent; - sendbuf_ += sent; - } - free(sendbuf); - ); - } - - /* Fetch message. */ - r = mds_message_read(&(information->message), socket_fd); - if (r == 0) - message_received(information); - else - if (r == -2) - { - eprint("corrupt message received."); - goto fail; - } - else if (errno == ECONNRESET) - { - r = mds_message_read(&(information->message), socket_fd); - information->open = 0; - if (r == 0) - message_received(information); - /* Connection closed. */ - break; - } - else if (errno == EINTR) - { - /* Stop the thread if we are re-exec:ing the server. */ - if (reexecing) - goto reexec; - } - else - { - perror(*argv); - goto fail; - } - } - /* Stop the thread if we are re-exec:ing the server. */ - if (reexecing) - goto reexec; - - - /* Multicast information about the client closing. */ - n = 2 * 10 + 1 + strlen("Client closed: :\n\n"); - snprintf(msgbuf, n, - "Client closed: %" PRIu32 ":%" PRIu32 "\n" - "\n", - (uint32_t)(information->id >> 32), - (uint32_t)(information->id >> 0)); - n = strlen(msgbuf) + 1; - multicast_message(msgbuf, n); - - - fail: /* The loop does break, this done on success as well. */ - /* Close socket and free resources. */ - close(socket_fd); - free(msgbuf); - if (information != NULL) - { - if (information->interception_conditions != NULL) - { - size_t i; - for (i = 0; i < information->interception_conditions_count; i++) - free(information->interception_conditions[i].condition); - free(information->interception_conditions); - } - if (mutex_created) - pthread_mutex_destroy(&(information->mutex)); - mds_message_destroy(&(information->message)); - free(information->send_pending); - free(information); - } - - /* Unlist client and decrease the slave count. */ - with_mutex(slave_mutex, - fd_table_remove(&client_map, socket_fd); - if (entry != LINKED_LIST_UNUSED) - linked_list_remove(&client_list, entry); - running_slaves--; - pthread_cond_signal(&slave_cond);); - - return NULL; - - - reexec: - /* Tell the master thread that the slave has closed, - this is done because re-exec causes a race-condition - between the acception of a slave and the execution - of the the slave thread. */ - with_mutex(slave_mutex, - running_slaves--; - pthread_cond_signal(&slave_cond);); - - return NULL; -} - - -/** - * Perform actions that should be taken when - * a message has been received from a client - * - * @param client The client has sent a message - */ -void message_received(client_t* client) -{ - mds_message_t message = client->message; - int assign_id = 0; - int modifying = 0; - int intercept = 0; - int64_t priority = 0; - int stop = 0; - const char* message_id = NULL; - size_t i, n; - char* msgbuf; - - - /* Parser headers. */ - for (i = 0; i < message.header_count; i++) - { - const char* h = message.headers[i]; - if (strequals(h, "Command: assign-id")) assign_id = 1; - else if (strequals(h, "Command: intercept")) intercept = 1; - else if (strequals(h, "Modifying: yes")) modifying = 1; - else if (strequals(h, "Stop: yes")) stop = 1; - else if (startswith(h, "Message ID: ")) message_id = strstr(h, ": ") + 2; - else if (startswith(h, "Priority: ")) priority = atoll(strstr(h, ": ") + 2); - } - - /* Ignore message if not labelled with a message ID. */ - if (message_id == NULL) - { - eprint("received message with a message ID, ignoring."); - return; - } - - /* Assign ID if not already assigned. */ - if (assign_id && (client->id == 0)) - { - intercept |= 2; - with_mutex(slave_mutex, - client->id = next_id++; - if (next_id == 0) - { - eprint("this is impossible, ID counter has overflowed."); - /* If the program ran for a millennium it would - take c:a 585 assignments per nanosecond. This - cannot possibly happen. (It would require serious - dedication by generations of ponies (or just an alicorn) - to maintain the process and transfer it new hardware.) */ - abort(); - } - ); - } - - /* Make the client listen for messages addressed to it. */ - if (intercept) - { - size_t size = 64; /* Atleast 25, otherwise we get into problems at ((intercept & 2)) */ - char* buf; - if (xmalloc(buf, size + 1, char)) - { - perror(*argv); - return; - } - - pthread_mutex_lock(&(client->mutex)); - if ((intercept & 1)) /* from payload */ - { - char* payload = client->message.payload; - if (client->message.payload_size == 0) /* All messages */ - { - *buf = '\0'; - add_intercept_condition(client, buf, priority, modifying, stop); - } - else /* Filtered messages */ - for (;;) - { - char* end = strchrnul(payload, '\n'); - size_t len = (size_t)(end - payload); - if (len == 0) - { - payload++; - break; - } - if (len > size) - { - char* old_buf = buf; - buf = realloc(buf, ((size <<= 1) + 1) * sizeof(char)); - if (buf == NULL) - { - perror(*argv); - free(old_buf); - return; - } - } - memcpy(buf, payload, len); - buf[len] = '\0'; - add_intercept_condition(client, buf, priority, modifying, stop); - if (*end == '\0') - break; - payload = end + 1; - } - } - if ((intercept & 2)) /* "To: $(client->id)" */ - { - snprintf(buf, size, "To: %" PRIu32 ":%" PRIu32, - (uint32_t)(client->id >> 32), - (uint32_t)(client->id >> 0)); - add_intercept_condition(client, buf, priority, modifying, stop); - } - pthread_mutex_unlock(&(client->mutex)); - - free(buf); - } - - - /* Multicast the message. */ - n = mds_message_marshal_size(&message, 0); - if ((msgbuf = malloc(n)) == NULL) - { - perror(*argv); - return; - } - mds_message_marshal(&message, msgbuf, 0); - multicast_message(msgbuf, n / sizeof(char)); /* TODO support re-exec */ - free(msgbuf); - - - /* Send asigned ID. */ - if (assign_id) - { - /* Construct response. */ - n = 2 * 10 + strlen(message_id) + 1; - n += strlen("ID assignment: :\nIn response to: \n\n"); - if (xmalloc(msgbuf, n, char)) - { - perror(*argv); - return; - } - snprintf(msgbuf, n, - "ID assignment: %" PRIu32 ":%" PRIu32 "\n" - "In response to: %s\n" - "\n", - (uint32_t)(client->id >> 32), - (uint32_t)(client->id >> 0), - message_id == NULL ? "" : message_id); - n = strlen(msgbuf); - - /* Multicast the reply. */ - multicast_message(msgbuf, n); /* TODO support re-exec */ - - /* Queue message to be sent when this function returns. - This done to simplify `multicast_message` for re-exec. */ - with_mutex(client->mutex, - if (client->send_pending_size == 0) - { - /* Set the pending message. */ - client->send_pending = msgbuf; - client->send_pending_size = n; - } - else - { - /* Concatenate message to already pending messages. */ - size_t new_len = client->send_pending_size + n; - char* msg_new = realloc(client->send_pending, new_len * sizeof(char)); - if (msg_new != NULL) - { - memcpy(msg_new + client->send_pending_size, msgbuf, n * sizeof(char)); - client->send_pending = msg_new; - client->send_pending_size = new_len; - } - else - perror(*argv); - free(msgbuf); - } - ); - } -} - - -/** - * Add an interception condition for a client - * - * @param client The client - * @param condition The header, optionally with value, to look for, or empty (not `NULL`) for all messages - * @param priority Interception priority - * @param modifying Whether the client may modify the messages - * @param stop Whether the condition should be removed rather than added - */ -void add_intercept_condition(client_t* client, char* condition, int64_t priority, int modifying, int stop) -{ - size_t n = client->interception_conditions_count; - interception_condition_t* conds = client->interception_conditions; - ssize_t nonmodifying = -1; - char* header = condition; - char* value; - size_t hash; - size_t i; - - if ((condition = strdup(condition)) == NULL) - { - perror(*argv); - return; - } - - if ((value = strchr(header, ':')) != NULL) - { - *value = '\0'; /* NUL-terminate header. */ - value += 2; /* Skip over delimiter. */ - } - - hash = string_hash(header); - - for (i = 0; i < n; i++) - { - if (conds[i].header_hash == hash) - if (strequals(conds[i].condition, condition)) - { - if (stop) - { - /* Remove the condition from the list. */ - memmove(conds + i, conds + i + 1, --n - i); - client->interception_conditions_count--; - /* Diminish the list. */ - if (n == 0) - { - free(conds); - client->interception_conditions = NULL; - } - else - if ((conds = realloc(conds, n * sizeof(interception_condition_t))) == NULL) - perror(*argv); - else - client->interception_conditions = conds; - } - else - { - /* Update parameters. */ - conds[i].priority = priority; - conds[i].modifying = modifying; - if (modifying && (nonmodifying >= 0)) - { - /* Optimisation: put conditions that are modifying - at the beginning. When a client is intercepting - we most know if any satisfying condition is - modifying. With this optimisation the first - satisfying condition will tell us if there is - any satisfying condition that is modifying. */ - interception_condition_t temp = conds[nonmodifying]; - conds[nonmodifying] = conds[i]; - conds[i] = temp; - } - } - return; - } - /* Look for the first non-modifying, this is a part of the - optimisation where we put all modifying conditions at the - beginning. */ - if ((nonmodifying < 0) && conds[i].modifying) - nonmodifying = (ssize_t)i; - } - - if (stop) - eprint("client tried to stop intercepting messages that it does not intercept."); - else - { - /* Grow the interception condition list. */ - if (conds == NULL) - conds = malloc(1 * sizeof(interception_condition_t)); - else - conds = realloc(conds, (n + 1) * sizeof(interception_condition_t)); - if (conds == NULL) - { - perror(*argv); - return; - } - client->interception_conditions = conds; - /* Store condition. */ - client->interception_conditions_count++; - conds[n].condition = condition; - conds[n].header_hash = hash; - conds[n].priority = priority; - conds[n].modifying = modifying; - if (modifying && (nonmodifying >= 0)) - { - /* Optimisation: put conditions that are modifying - at the beginning. When a client is intercepting - we most know if any satisfying condition is - modifying. With this optimisation the first - satisfying condition will tell us if there is - any satisfying condition that is modifying. */ - interception_condition_t temp = conds[nonmodifying]; - conds[nonmodifying] = conds[n]; - conds[n] = temp; - } - } -} - - -/** - * Compare two queued interceptors by priority - * - * @param a:const queued_interception_t* One of the interceptors - * @param b:const queued_interception_t* The other of the two interceptors - * @return Negative if a before b, positive if a after b, otherwise zero - */ -static int cmp_queued_interception(const void* a, const void* b) -{ - const queued_interception_t* p = b; /* Highest first, so swap them. */ - const queued_interception_t* q = a; - int64_t diff = p->priority - q->priority; - return diff < 0 ? -1 : diff > 0 ? 1 : 0; -} - - -/** - * Multicast a message - * - * @param message The message - * @param length The length of the message - */ -void multicast_message(char* message, size_t length) -{ - size_t header_count = 0; - size_t n = length - 1; - size_t* hashes = NULL; - char** headers = NULL; - char** header_values = NULL; - queued_interception_t* interceptions = NULL; - size_t interceptions_count = 0; - size_t i; - ssize_t node; - - /* Count the number of headers. */ - for (i = 0; i < n; i++) - if (message[i] == '\n') - { - header_count++; - if (message[i + 1] == '\n') - break; - } - - if (header_count == 0) - return; /* Invalid message. */ - - /* Allocate header lists. */ - if (xmalloc(hashes, header_count, size_t)) goto fail; - if (xmalloc(headers, header_count, char*)) goto fail; - if (xmalloc(header_values, header_count, char*)) goto fail; - - /* Populate header lists. */ - for (i = 0; i < header_count; i++) - { - char* end = strchr(message, '\n'); - char* colon = strchr(message, ':'); - - *end = '\0'; - if ((header_values[i] = strdup(message)) == NULL) - { - header_count = i; - goto fail; - } - *colon = '\0'; - if ((headers[i] = strdup(message)) == NULL) - { - free(headers[i]); - header_count = i; - goto fail; - } - *colon = ':'; - *end = '\n'; - hashes[i] = string_hash(headers[i]); - - message = end + 1; - } - - /* Get intercepting clients. */ - with_mutex(slave_mutex, - /* Count clients. */ - n = 0; - foreach_linked_list_node (client_list, node) - n++; - - /* Allocate interceptor list. */ - interceptions = malloc(n * sizeof(queued_interception_t*)); - - /* Search clients. */ - if (interceptions != NULL) - foreach_linked_list_node (client_list, node) - { - client_t* client = (client_t*)(void*)(client_list.values[node]); - pthread_mutex_t mutex = client->mutex; - interception_condition_t* conds = client->interception_conditions; - int64_t priority = 0; /* Initialise to stop incorrect warning. */ - int modifying = 0; /* Initialise to stop incorrect warning. */ - size_t j; - - /* Look for a matching condition. */ - n = client->interception_conditions_count; - with_mutex(mutex, - for (i = 0; i < n; i++) - { - interception_condition_t* cond = conds + i; - for (j = 0; j < header_count; j++) - { - if (*(cond->condition) == '\0') - break; - if (cond->header_hash == hashes[j]) - if (strequals(cond->condition, headers[j]) || - strequals(cond->condition, header_values[j])) - break; - } - if (j < header_count) - { - priority = cond->priority; - modifying = cond->modifying; - break; - } - } - ); - - /* List client of there was a matching condition. */ - if (i < n) - { - interceptions[interceptions_count].client = client; - interceptions[interceptions_count].priority = priority; - interceptions[interceptions_count].modifying = modifying; - interceptions_count++; - } - } - ); - if (interceptions == NULL) - goto fail; - - /* Sort interceptors. */ - qsort(interceptions, interceptions_count, sizeof(queued_interception_t), cmp_queued_interception); - - /* Send message to interceptors. */ - for (i = 0; i < interceptions_count; i++) - { - queued_interception_t client_ = interceptions[i]; - client_t* client = client_.client; - char* msg = message; - size_t sent; - n = length; - - /* Send the message. */ - with_mutex(client->mutex, - if (client->open) - while (n > 0) - { - sent = send_message(client->socket_fd, msg, n); - if ((sent < n) && (errno != EINTR)) /* TODO Support reexec */ - { - perror(*argv); - break; - } - n -= sent; - msg += sent; - } - ); - - /* Wait for a reply. */ - if ((n > 0) && client_.modifying) - { - /* TODO */ - } - } - - - errno = 0; - fail: /* This is done before this function returns even if there was no error. */ - if (errno != 0) - perror(*argv); - /* Release resources. */ - xfree(headers, header_count); - xfree(header_values, header_count); - free(interceptions); - free(hashes); -} - - -/** - * Exec into the mdsinitrc script - * - * @param args The arguments to the child process - */ -void run_initrc(char** args) -{ - char pathname[PATH_MAX]; - struct passwd* pwd; - char* env; - char* home; - args[0] = pathname; - -#define __exec(FORMAT, ...) \ - xsnprintf(pathname, FORMAT, __VA_ARGS__); execv(args[0], args) - - /* Test $XDG_CONFIG_HOME. */ - if ((env = getenv_nonempty("XDG_CONFIG_HOME")) != NULL) - { - __exec("%s/%s", env, INITRC_FILE); - } - - /* Test $HOME. */ - if ((env = getenv_nonempty("HOME")) != NULL) - { - __exec("%s/.config/%s", env, INITRC_FILE); - __exec("%s/.%s", env, INITRC_FILE); - } - - /* Test ~. */ - pwd = getpwuid(getuid()); /* Ignore error. */ - if (pwd != NULL) - { - home = pwd->pw_dir; - if ((home != NULL) && (*home != '\0')) - { - __exec("%s/.config/%s", home, INITRC_FILE); - __exec("%s/.%s", home, INITRC_FILE); - } - } - - /* Test $XDG_CONFIG_DIRS. */ - if ((env = getenv_nonempty("XDG_CONFIG_DIRS")) != NULL) - { - char* begin = env; - char* end; - int len; - for (;;) - { - end = strchrnul(begin, ':'); - len = (int)(end - begin); - if (len > 0) - { - __exec("%.*s/%s", len, begin, INITRC_FILE); - } - if (*end == '\0') - break; - begin = end + 1; - } - } - - /* Test /etc. */ - __exec("%s/%s", SYSCONFDIR, INITRC_FILE); - -#undef __exec - - /* Everything failed. */ - eprintf("unable to run %s file, you might as well kill me.", INITRC_FILE); -} - - -/** - * Called with the signal SIGUSR1 is caught. - * This function should cue a re-exec of the program. - * - * @param signo The caught signal - */ -void sigusr1_trap(int signo) -{ - if (reexecing == 0) - { - pthread_t current_thread; - ssize_t node; - - reexecing = 1; - current_thread = pthread_self(); - - if (pthread_equal(current_thread, master_thread) == 0) - pthread_kill(master_thread, signo); - - with_mutex(slave_mutex, - foreach_linked_list_node (client_list, node) - { - client_t* value = (client_t*)(void*)(client_list.values[node]); - if (pthread_equal(current_thread, value->thread) == 0) - pthread_kill(value->thread, signo); - }); - } -} - - -/** - * Marshal the server's state into a file - * - * @param fd The file descriptor - * @return Negative on error - */ -int marshal_server(int fd) -{ - size_t list_size = linked_list_marshal_size(&client_list); - size_t map_size = fd_table_marshal_size(&client_map); - size_t list_elements = 0; - size_t msg_size = 0; - char* state_buf = NULL; - char* state_buf_; - size_t state_n; - ssize_t wrote; - ssize_t node; - size_t j, n; - - - /* Calculate the grand size of all messages and their buffers. */ - for (node = client_list.edge;; list_elements++) - { - mds_message_t message; - client_t* value; - if ((node = client_list.next[node]) == client_list.edge) - break; - - value = (client_t*)(void*)(client_list.values[node]); - n = value->interception_conditions_count; - message = value->message; - msg_size += mds_message_marshal_size(&message, 1); - msg_size += n * (sizeof(size_t) + sizeof(int64_t) + sizeof(int)); - msg_size += value->send_pending_size * sizeof(char); - - for (j = 0; j < n; j++) - msg_size += (strlen(value->interception_conditions[j].condition) + 1) * sizeof(char); - } - - /* Calculate the grand size of all client information. */ - state_n = 6 + sizeof(size_t) + 2 * sizeof(int) + 1 * sizeof(uint64_t); - state_n *= list_elements; - state_n += msg_size; - - /* Add the size of the rest of the program's state. */ - state_n += 2 * sizeof(int) + 1 * sizeof(sig_atomic_t) + 2 * sizeof(size_t); - - /* Allocate a buffer for all data except the client list and the client map. */ - state_buf = state_buf_ = malloc(state_n); - if (state_buf == NULL) - goto fail; - - - /* Tell the new version of the program what version of the program it is marshalling. */ - buf_set_next(state_buf_, int, MDS_SERVER_VARS_VERSION); - - /* Marshal the miscellaneous state data. */ - buf_set_next(state_buf_, sig_atomic_t, running); - buf_set_next(state_buf_, uint64_t, next_id); - - /* Tell the program how large the marshalled client list is and how any clients are marshalled. */ - buf_set_next(state_buf_, size_t, list_size); - buf_set_next(state_buf_, size_t, list_elements); - - /* Marshal the clients. */ - foreach_linked_list_node (client_list, node) - { - /* Get the memory address of the client. */ - size_t value_address = client_list.values[node]; - /* Get the client's information. */ - client_t* value = (client_t*)(void*)value_address; - - /* Get the marshalled size of the message. */ - msg_size = mds_message_marshal_size(&(value->message), 1); - - /* Marshal the address, it is used the the client list and the client map, that will be marshalled. */ - buf_set_next(state_buf_, size_t, value_address); - /* Tell the program how large the marshalled message is. */ - buf_set_next(state_buf_, size_t, msg_size); - /* Marshal the client info. */ - buf_set_next(state_buf_, ssize_t, value->list_entry); - buf_set_next(state_buf_, int, value->socket_fd); - buf_set_next(state_buf_, int, value->open); - buf_set_next(state_buf_, uint64_t, value->id); - /* Marshal the pending messages. */ - buf_set_next(state_buf_, size_t, value->send_pending_size); - if (value->send_pending_size > 0) - { - memcpy(state_buf_, value->send_pending, value->send_pending_size * sizeof(char)); - state_buf_ += value->send_pending_size; - } - /* Marshal interception conditions. */ - buf_set_next(state_buf_, size_t, n = value->interception_conditions_count); - for (j = 0; j < n; j++) - { - interception_condition_t cond = value->interception_conditions[j]; - memcpy(state_buf_, cond.condition, strlen(cond.condition) + 1); - buf_next(state_buf_, char, strlen(cond.condition) + 1); - buf_set_next(state_buf_, size_t, cond.header_hash); - buf_set_next(state_buf_, int64_t, cond.priority); - buf_set_next(state_buf_, int, cond.modifying); - } - /* Marshal the message. */ - mds_message_marshal(&(value->message), state_buf_, 1); - state_buf_ += msg_size / sizeof(char); - } - - - /* Send the marshalled data into the file. */ - while (state_n > 0) - { - errno = 0; - wrote = write(fd, state_buf, state_n); - if (errno && (errno != EINTR)) - goto fail; - state_n -= (size_t)max(wrote, 0); - state_buf += (size_t)max(wrote, 0); - } - free(state_buf); - - /* Marshal, and send into the file, the client list. */ - state_buf = malloc(list_size); - if (state_buf == NULL) - goto fail; - linked_list_marshal(&client_list, state_buf); - while (list_size > 0) - { - errno = 0; - wrote = write(fd, state_buf, list_size); - if (errno && (errno != EINTR)) - goto fail; - list_size -= (size_t)max(wrote, 0); - state_buf += (size_t)max(wrote, 0); - } - free(state_buf); - - /* Marshal, and send into the file, the client map. */ - state_buf = malloc(map_size); - if (state_buf == NULL) - goto fail; - fd_table_marshal(&client_map, state_buf); - while (map_size > 0) - { - errno = 0; - wrote = write(fd, state_buf, map_size); - if (errno && (errno != EINTR)) - goto fail; - map_size -= (size_t)max(wrote, 0); - state_buf += (size_t)max(wrote, 0); - } - free(state_buf); - - return 0; - - fail: - free(state_buf); - return -1; -} - - -/** - * Address translation table used by `unmarshal_server` and `remapper` - */ -static hash_table_t unmarshal_remap_map; - -/** - * Address translator for `unmarshal_server` - * - * @param old The old address - * @return The new address - */ -static size_t unmarshal_remapper(size_t old) -{ - return hash_table_get(&unmarshal_remap_map, old); -} - -/** - * Unmarshal the server's state from a file - * - * @param fd The file descriptor - * @return Negative on error - */ -int unmarshal_server(int fd) -{ - int with_error = 0; - size_t state_buf_size = 8 << 10; - size_t state_buf_ptr = 0; - ssize_t got; - char* state_buf; - char* state_buf_; - size_t list_size; - size_t list_elements; - size_t i; - ssize_t node; - pthread_t _slave_thread; - - - /* Allocate buffer for data. */ - if (xmalloc(state_buf = state_buf_, state_buf_size, char)) - { - perror(*argv); - return -1; - } - - /* Read the file. */ - for (;;) - { - /* Grow buffer if it is too small. */ - if (state_buf_size == state_buf_ptr) - { - char* old_buf = state_buf; - state_buf = realloc(state_buf, (state_buf_size <<= 1) * sizeof(char)); - if (state_buf == NULL) - { - perror(*argv); - free(old_buf); - return -1; - } - } - - /* Read from the file into the buffer. */ - got = read(fd, state_buf + state_buf_ptr, state_buf_size - state_buf_ptr); - if (got < 0) - { - perror(*argv); - free(state_buf); - return -1; - } - if (got == 0) - break; - state_buf_ptr += (size_t)got; - } - - - /* Create memory address remapping table. */ - if (hash_table_create(&unmarshal_remap_map)) - { - perror(*argv); - free(state_buf); - hash_table_destroy(&unmarshal_remap_map, NULL, NULL); - return -1; - } - - - /* Get the marshal protocal version. Not needed, there is only the one version right now. */ - /* buf_get(state_buf_, int, 0, MDS_SERVER_VARS_VERSION); */ - buf_next(state_buf_, int, 1); - - /* Unmarshal the miscellaneous state data. */ - buf_get_next(state_buf_, sig_atomic_t, running); - buf_get_next(state_buf_, uint64_t, next_id); - - /* Get the marshalled size of the client list and how any clients that are marshalled. */ - buf_get_next(state_buf_, size_t, list_size); - buf_get_next(state_buf_, size_t, list_elements); - - /* Unmarshal the clients. */ - for (i = 0; i < list_elements; i++) - { - size_t seek = 0; - size_t j = 0, n = 0; - size_t value_address; - size_t msg_size; - client_t* value; - - /* Allocate the client's information. */ - if (xmalloc(value, 1, client_t)) - { - perror(*argv); - goto clients_fail; - } - - /* Unmarshal the address, it is used the the client list and the client map, that are also marshalled. */ - buf_get_next(state_buf_, size_t, value_address); - /* Get the marshalled size of the message. */ - buf_get_next(state_buf_, size_t, msg_size); - /* Unmarshal the client info. */ - buf_get_next(state_buf_, ssize_t, value->list_entry); - buf_get_next(state_buf_, int, value->socket_fd); - buf_get_next(state_buf_, int, value->open); - buf_get_next(state_buf_, uint64_t, value->id); - /* Unmarshal the pending messages. */ - buf_get_next(state_buf_, size_t, value->send_pending_size); - if (value->send_pending_size > 0) - { - if (xmalloc(value->send_pending, value->send_pending_size, char)) - { - perror(*argv); - goto clients_fail; - } - memcpy(value->send_pending, state_buf_, value->send_pending_size * sizeof(char)); - state_buf_ += value->send_pending_size; - } - else - value->send_pending = NULL; - /* Unmarshal interception conditions. */ - buf_get_next(state_buf_, size_t, value->interception_conditions_count = n); - seek = 6 * sizeof(size_t) + 2 * sizeof(int) + 1 * sizeof(uint64_t); - if (xmalloc(value->interception_conditions, n, interception_condition_t)) - { - perror(*argv); - goto clients_fail; - } - for (j = 0; j < n; j++) - { - interception_condition_t* cond = value->interception_conditions + j; - size_t m = strlen(state_buf_) + 1; - if (xmalloc(cond->condition, m, char)) - { - perror(*argv); - goto clients_fail; - } - memcpy(cond->condition, state_buf_, m); - buf_next(state_buf_, char, m); - buf_get_next(state_buf_, size_t, cond->header_hash); - buf_get_next(state_buf_, int64_t, cond->priority); - buf_get_next(state_buf_, int, cond->modifying); - seek += m * sizeof(char) + sizeof(size_t) + sizeof(int64_t) + sizeof(int); - } - /* Unmarshal the message. */ - if (mds_message_unmarshal(&(value->message), state_buf_)) - { - perror(*argv); - mds_message_destroy(&(value->message)); - goto clients_fail; - } - state_buf_ += msg_size / sizeof(char); - - /* Populate the remapping table. */ - hash_table_put(&unmarshal_remap_map, value_address, (size_t)(void*)value); - - - /* On error, seek past all clients. */ - continue; - clients_fail: - with_error = 1; - if (value != NULL) - { - if (value->interception_conditions != NULL) - { - for (j = 0; j < n; j++) - free(value->interception_conditions[j].condition); - free(value->interception_conditions); - } - free(value->send_pending); - free(value); - } - state_buf_ -= seek / sizeof(char); - for (; i < list_elements; i++) - { - /* There is not need to close the sockets, it is done by - the caller because there are conditions where we cannot - get here anyway. */ - msg_size = ((size_t*)state_buf_)[1]; - buf_next(state_buf_, size_t, 4); - buf_next(state_buf_, int, 2); - buf_next(state_buf_, uint64_t, 1); - buf_get_next(state_buf_, size_t, n); - for (j = 0; j < n; j++) - { - buf_next(state_buf_, char, strlen(state_buf_) + 1); - buf_next(state_buf_, size_t, 1); - buf_next(state_buf_, int64_t, 1); - buf_next(state_buf_, int, 1); - } - state_buf_ += msg_size / sizeof(char); - } - break; - } - - /* Unmarshal the client list. */ - linked_list_unmarshal(&client_list, state_buf_); - state_buf_ += list_size / sizeof(char); - - /* Unmarshal the client map. */ - fd_table_unmarshal(&client_map, state_buf_, unmarshal_remapper); - - /* Release the raw data. */ - free(state_buf); - - /* Remove non-found elements from the fd table. */ - if (with_error) - for (i = 0; i < client_map.capacity; i++) - if (client_map.used[i / 64] & ((uint64_t)1 << (i % 64))) - if (client_map.values[i] == 0) /* Lets not presume that fd-table actually initialise its allocations. */ - client_map.used[i / 64] &= ~((uint64_t)1 << (i % 64)); - - /* Remap the linked list and remove non-found elements, and start the clients. */ - foreach_linked_list_node (client_list, node) - { - /* Remap the linked list and remove non-found elements. */ - size_t new_address = unmarshal_remapper(client_list.values[node]); - client_list.values[node] = new_address; - if (new_address == 0) /* Returned if missing (or if the address is the invalid NULL.) */ - linked_list_remove(&client_list, node); - else - { - /* Start the clients. (Errors do not need to be reported.) */ - client_t* client = (client_t*)(void*)new_address; - int socket_fd = client->socket_fd; - - /* Increase number of running slaves. */ - with_mutex(slave_mutex, running_slaves++;); - - /* Start slave thread. */ - errno = pthread_create(&_slave_thread, NULL, slave_loop, (void*)(intptr_t)socket_fd); - if (errno) - { - perror(*argv); - with_mutex(slave_mutex, running_slaves--;); - } - } - } - - /* Release the remapping table's resources. */ - hash_table_destroy(&unmarshal_remap_map, NULL, NULL); - - return -with_error; -} - |