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2d77f6fcf8
Handling a host mconsole version request must be done in a process context rather than interrupt context now that utsname information can be process-specific rather than global. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
228 lines
5.6 KiB
C
228 lines
5.6 KiB
C
/*
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* Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org)
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* Copyright (C) 2001 - 2003 Jeff Dike (jdike@addtoit.com)
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* Licensed under the GPL
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <errno.h>
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#include <signal.h>
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#include <sys/socket.h>
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#include <sys/types.h>
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#include <sys/uio.h>
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#include <sys/un.h>
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#include <unistd.h>
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#include "user.h"
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#include "mconsole.h"
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#include "umid.h"
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static struct mconsole_command commands[] = {
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/* With uts namespaces, uts information becomes process-specific, so
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* we need a process context. If we try handling this in interrupt
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* context, we may hit an exiting process without a valid uts
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* namespace.
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*/
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{ "version", mconsole_version, MCONSOLE_PROC },
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{ "halt", mconsole_halt, MCONSOLE_PROC },
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{ "reboot", mconsole_reboot, MCONSOLE_PROC },
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{ "config", mconsole_config, MCONSOLE_PROC },
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{ "remove", mconsole_remove, MCONSOLE_PROC },
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{ "sysrq", mconsole_sysrq, MCONSOLE_INTR },
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{ "help", mconsole_help, MCONSOLE_INTR },
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{ "cad", mconsole_cad, MCONSOLE_INTR },
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{ "stop", mconsole_stop, MCONSOLE_PROC },
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{ "go", mconsole_go, MCONSOLE_INTR },
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{ "log", mconsole_log, MCONSOLE_INTR },
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{ "proc", mconsole_proc, MCONSOLE_PROC },
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{ "stack", mconsole_stack, MCONSOLE_INTR },
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};
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/* Initialized in mconsole_init, which is an initcall */
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char mconsole_socket_name[256];
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int mconsole_reply_v0(struct mc_request *req, char *reply)
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{
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struct iovec iov;
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struct msghdr msg;
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iov.iov_base = reply;
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iov.iov_len = strlen(reply);
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msg.msg_name = &(req->origin);
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msg.msg_namelen = req->originlen;
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msg.msg_iov = &iov;
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msg.msg_iovlen = 1;
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msg.msg_control = NULL;
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msg.msg_controllen = 0;
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msg.msg_flags = 0;
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return sendmsg(req->originating_fd, &msg, 0);
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}
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static struct mconsole_command *mconsole_parse(struct mc_request *req)
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{
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struct mconsole_command *cmd;
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int i;
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for(i=0;i<sizeof(commands)/sizeof(commands[0]);i++){
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cmd = &commands[i];
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if(!strncmp(req->request.data, cmd->command,
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strlen(cmd->command))){
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return(cmd);
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}
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}
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return(NULL);
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}
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#define MIN(a,b) ((a)<(b) ? (a):(b))
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#define STRINGX(x) #x
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#define STRING(x) STRINGX(x)
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int mconsole_get_request(int fd, struct mc_request *req)
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{
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int len;
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req->originlen = sizeof(req->origin);
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req->len = recvfrom(fd, &req->request, sizeof(req->request), 0,
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(struct sockaddr *) req->origin, &req->originlen);
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if (req->len < 0)
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return 0;
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req->originating_fd = fd;
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if(req->request.magic != MCONSOLE_MAGIC){
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/* Unversioned request */
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len = MIN(sizeof(req->request.data) - 1,
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strlen((char *) &req->request));
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memmove(req->request.data, &req->request, len);
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req->request.data[len] = '\0';
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req->request.magic = MCONSOLE_MAGIC;
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req->request.version = 0;
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req->request.len = len;
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mconsole_reply_v0(req, "ERR Version 0 mconsole clients are "
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"not supported by this driver");
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return(0);
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}
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if(req->request.len >= MCONSOLE_MAX_DATA){
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mconsole_reply(req, "Request too large", 1, 0);
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return(0);
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}
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if(req->request.version != MCONSOLE_VERSION){
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mconsole_reply(req, "This driver only supports version "
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STRING(MCONSOLE_VERSION) " clients", 1, 0);
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}
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req->request.data[req->request.len] = '\0';
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req->cmd = mconsole_parse(req);
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if(req->cmd == NULL){
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mconsole_reply(req, "Unknown command", 1, 0);
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return(0);
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}
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return(1);
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}
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int mconsole_reply_len(struct mc_request *req, const char *str, int total,
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int err, int more)
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{
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struct mconsole_reply reply;
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int len, n;
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do {
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reply.err = err;
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/* err can only be true on the first packet */
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err = 0;
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len = MIN(total, MCONSOLE_MAX_DATA - 1);
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if(len == total) reply.more = more;
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else reply.more = 1;
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memcpy(reply.data, str, len);
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reply.data[len] = '\0';
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total -= len;
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str += len;
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reply.len = len + 1;
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len = sizeof(reply) + reply.len - sizeof(reply.data);
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n = sendto(req->originating_fd, &reply, len, 0,
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(struct sockaddr *) req->origin, req->originlen);
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if(n < 0) return(-errno);
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} while(total > 0);
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return(0);
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}
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int mconsole_reply(struct mc_request *req, const char *str, int err, int more)
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{
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return mconsole_reply_len(req, str, strlen(str), err, more);
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}
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int mconsole_unlink_socket(void)
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{
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unlink(mconsole_socket_name);
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return 0;
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}
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static int notify_sock = -1;
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int mconsole_notify(char *sock_name, int type, const void *data, int len)
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{
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struct sockaddr_un target;
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struct mconsole_notify packet;
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int n, err = 0;
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lock_notify();
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if(notify_sock < 0){
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notify_sock = socket(PF_UNIX, SOCK_DGRAM, 0);
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if(notify_sock < 0){
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err = -errno;
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printk("mconsole_notify - socket failed, errno = %d\n",
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err);
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}
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}
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unlock_notify();
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if(err)
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return(err);
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target.sun_family = AF_UNIX;
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strcpy(target.sun_path, sock_name);
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packet.magic = MCONSOLE_MAGIC;
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packet.version = MCONSOLE_VERSION;
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packet.type = type;
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len = (len > sizeof(packet.data)) ? sizeof(packet.data) : len;
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packet.len = len;
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memcpy(packet.data, data, len);
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err = 0;
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len = sizeof(packet) + packet.len - sizeof(packet.data);
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n = sendto(notify_sock, &packet, len, 0, (struct sockaddr *) &target,
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sizeof(target));
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if(n < 0){
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err = -errno;
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printk("mconsole_notify - sendto failed, errno = %d\n", errno);
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}
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return(err);
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}
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/*
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* Overrides for Emacs so that we follow Linus's tabbing style.
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* Emacs will notice this stuff at the end of the file and automatically
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* adjust the settings for this buffer only. This must remain at the end
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* of the file.
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* ---------------------------------------------------------------------------
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* Local variables:
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* c-file-style: "linux"
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* End:
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*/
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