X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Futmp-wtmp.c;h=217ae1e2c734ceca3168f1bbeb00463cc9766dbb;hp=cb3f201322edbef648ca68b7bf5cb8933d231711;hb=0071d9f1db6dc9a1035cf5afb81455b67ed462f6;hpb=e99e38bbdcca3fe5956823bdb3d38544ccf93221

diff --git a/src/utmp-wtmp.c b/src/utmp-wtmp.c
index cb3f20132..217ae1e2c 100644
--- a/src/utmp-wtmp.c
+++ b/src/utmp-wtmp.c
@@ -1,4 +1,4 @@
-/*-*- Mode: C; c-basic-offset: 8 -*-*/
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
 
 /***
   This file is part of systemd.
@@ -24,6 +24,9 @@
 #include <assert.h>
 #include <string.h>
 #include <sys/utsname.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/poll.h>
 
 #include "macro.h"
 #include "utmp-wtmp.h"
@@ -89,19 +92,26 @@ int utmp_get_runlevel(int *runlevel, int *previous) {
         return r;
 }
 
-static void init_entry(struct utmpx *store, usec_t timestamp) {
-        struct utsname uts;
-
+static void init_timestamp(struct utmpx *store, usec_t t) {
         assert(store);
 
         zero(*store);
-        zero(uts);
 
-        if (timestamp <= 0)
-                timestamp = now(CLOCK_REALTIME);
+        if (t <= 0)
+                t = now(CLOCK_REALTIME);
 
-        store->ut_tv.tv_sec = timestamp / USEC_PER_SEC;
-        store->ut_tv.tv_usec = timestamp % USEC_PER_SEC;
+        store->ut_tv.tv_sec = t / USEC_PER_SEC;
+        store->ut_tv.tv_usec = t % USEC_PER_SEC;
+}
+
+static void init_entry(struct utmpx *store, usec_t t) {
+        struct utsname uts;
+
+        assert(store);
+
+        init_timestamp(store, t);
+
+        zero(uts);
 
         if (uname(&uts) >= 0)
                 strncpy(store->ut_host, uts.release, sizeof(store->ut_host));
@@ -145,11 +155,11 @@ static int write_entry_wtmp(const struct utmpx *store) {
         return -errno;
 }
 
-static int write_entry_both(const struct utmpx *store) {
+static int write_utmp_wtmp(const struct utmpx *store_utmp, const struct utmpx *store_wtmp) {
         int r, s;
 
-        r = write_entry_utmp(store);
-        s = write_entry_wtmp(store);
+        r = write_entry_utmp(store_utmp);
+        s = write_entry_wtmp(store_wtmp);
 
         if (r >= 0)
                 r = s;
@@ -162,10 +172,14 @@ static int write_entry_both(const struct utmpx *store) {
         return r;
 }
 
-int utmp_put_shutdown(usec_t timestamp) {
+static int write_entry_both(const struct utmpx *store) {
+        return write_utmp_wtmp(store, store);
+}
+
+int utmp_put_shutdown(void) {
         struct utmpx store;
 
-        init_entry(&store, timestamp);
+        init_entry(&store, 0);
 
         store.ut_type = RUN_LVL;
         strncpy(store.ut_user, "shutdown", sizeof(store.ut_user));
@@ -173,10 +187,10 @@ int utmp_put_shutdown(usec_t timestamp) {
         return write_entry_both(&store);
 }
 
-int utmp_put_reboot(usec_t timestamp) {
+int utmp_put_reboot(usec_t t) {
         struct utmpx store;
 
-        init_entry(&store, timestamp);
+        init_entry(&store, t);
 
         store.ut_type = BOOT_TIME;
         strncpy(store.ut_user, "reboot", sizeof(store.ut_user));
@@ -184,7 +198,72 @@ int utmp_put_reboot(usec_t timestamp) {
         return write_entry_both(&store);
 }
 
-int utmp_put_runlevel(usec_t timestamp, int runlevel, int previous) {
+static const char *sanitize_id(const char *id) {
+        size_t l;
+
+        assert(id);
+        l = strlen(id);
+
+        if (l <= sizeof(((struct utmpx*) NULL)->ut_id))
+                return id;
+
+        return id + l - sizeof(((struct utmpx*) NULL)->ut_id);
+}
+
+int utmp_put_init_process(const char *id, pid_t pid, pid_t sid, const char *line) {
+        struct utmpx store;
+
+        assert(id);
+
+        init_timestamp(&store, 0);
+
+        store.ut_type = INIT_PROCESS;
+        store.ut_pid = pid;
+        store.ut_session = sid;
+
+        strncpy(store.ut_id, sanitize_id(id), sizeof(store.ut_id));
+
+        if (line)
+                strncpy(store.ut_line, file_name_from_path(line), sizeof(store.ut_line));
+
+        return write_entry_both(&store);
+}
+
+int utmp_put_dead_process(const char *id, pid_t pid, int code, int status) {
+        struct utmpx lookup, store, store_wtmp, *found;
+
+        assert(id);
+
+        setutxent();
+
+        zero(lookup);
+        lookup.ut_type = INIT_PROCESS; /* looks for DEAD_PROCESS, LOGIN_PROCESS, USER_PROCESS, too */
+        strncpy(lookup.ut_id, sanitize_id(id), sizeof(lookup.ut_id));
+
+        if (!(found = getutxid(&lookup)))
+                return 0;
+
+        if (found->ut_pid != pid)
+                return 0;
+
+        memcpy(&store, found, sizeof(store));
+        store.ut_type = DEAD_PROCESS;
+        store.ut_exit.e_termination = code;
+        store.ut_exit.e_exit = status;
+
+        zero(store.ut_user);
+        zero(store.ut_host);
+        zero(store.ut_tv);
+
+        memcpy(&store_wtmp, &store, sizeof(store_wtmp));
+        /* wtmp wants the current time */
+        init_timestamp(&store_wtmp, 0);
+
+        return write_utmp_wtmp(&store, &store_wtmp);
+}
+
+
+int utmp_put_runlevel(int runlevel, int previous) {
         struct utmpx store;
         int r;
 
@@ -199,12 +278,12 @@ int utmp_put_runlevel(usec_t timestamp, int runlevel, int previous) {
 
                         previous = 0;
                 }
-
-                if (previous == runlevel)
-                        return 0;
         }
 
-        init_entry(&store, timestamp);
+        if (previous == runlevel)
+                return 0;
+
+        init_entry(&store, 0);
 
         store.ut_type = RUN_LVL;
         store.ut_pid = (runlevel & 0xFF) | ((previous & 0xFF) << 8);
@@ -212,3 +291,140 @@ int utmp_put_runlevel(usec_t timestamp, int runlevel, int previous) {
 
         return write_entry_both(&store);
 }
+
+#define TIMEOUT_MSEC 50
+
+static int write_to_terminal(const char *tty, const char *message) {
+        int fd, r;
+        const char *p;
+        size_t left;
+        usec_t end;
+
+        assert(tty);
+        assert(message);
+
+        if ((fd = open(tty, O_WRONLY|O_NDELAY|O_NOCTTY|O_CLOEXEC)) < 0)
+                return -errno;
+
+        if (!isatty(fd)) {
+                r = -errno;
+                goto finish;
+        }
+
+        p = message;
+        left = strlen(message);
+
+        end = now(CLOCK_MONOTONIC) + TIMEOUT_MSEC*USEC_PER_MSEC;
+
+        while (left > 0) {
+                ssize_t n;
+                struct pollfd pollfd;
+                usec_t t;
+                int k;
+
+                t = now(CLOCK_MONOTONIC);
+
+                if (t >= end) {
+                        r = -ETIME;
+                        goto finish;
+                }
+
+                zero(pollfd);
+                pollfd.fd = fd;
+                pollfd.events = POLLOUT;
+
+                if ((k = poll(&pollfd, 1, (end - t) / USEC_PER_MSEC)) < 0)
+                        return -errno;
+
+                if (k <= 0) {
+                        r = -ETIME;
+                        goto finish;
+                }
+
+                if ((n = write(fd, p, left)) < 0) {
+
+                        if (errno == EAGAIN)
+                                continue;
+
+                        r = -errno;
+                        goto finish;
+                }
+
+                assert((size_t) n <= left);
+
+                p += n;
+                left -= n;
+        }
+
+        r = 0;
+
+finish:
+        close_nointr_nofail(fd);
+
+        return r;
+}
+
+int utmp_wall(const char *message, bool (*match_tty)(const char *tty)) {
+        struct utmpx *u;
+        char date[FORMAT_TIMESTAMP_MAX];
+        char *text = NULL, *hn = NULL, *un = NULL, *tty = NULL;
+        int r;
+
+        if (!(hn = gethostname_malloc()) ||
+            !(un = getlogname_malloc())) {
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        getttyname_harder(STDIN_FILENO, &tty);
+
+        if (asprintf(&text,
+                     "\a\r\n"
+                     "Broadcast message from %s@%s%s%s (%s):\r\n\r\n"
+                     "%s\r\n\r\n",
+                     un, hn,
+                     tty ? " on " : "", strempty(tty),
+                     format_timestamp(date, sizeof(date), now(CLOCK_REALTIME)),
+                     message) < 0) {
+                r = -ENOMEM;
+                goto finish;
+        }
+
+        setutxent();
+
+        r = 0;
+
+        while ((u = getutxent())) {
+                int q;
+                const char *path;
+                char *buf = NULL;
+
+                if (u->ut_type != USER_PROCESS || u->ut_user[0] == 0)
+                        continue;
+
+                if (path_startswith(u->ut_line, "/dev/"))
+                        path = u->ut_line;
+                else {
+                        if (asprintf(&buf, "/dev/%s", u->ut_line) < 0) {
+                                r = -ENOMEM;
+                                goto finish;
+                        }
+
+                        path = buf;
+                }
+
+                if (!match_tty || match_tty(path))
+                        if ((q = write_to_terminal(path, text)) < 0)
+                                r = q;
+
+                free(buf);
+        }
+
+finish:
+        free(hn);
+        free(un);
+        free(tty);
+        free(text);
+
+        return r;
+}