chiark / gitweb /
exec: hangup/reset/deallocate VTs in gettys
[elogind.git] / src / util.c
index 5029896ef0635d507fcb9bc8e6e10dab537c81d3..14aa1f97280a5a8f700a3cf7d1b2cd044c08bae8 100644 (file)
@@ -1209,6 +1209,26 @@ char **strv_path_canonicalize(char **l) {
         return l;
 }
 
+char **strv_path_remove_empty(char **l) {
+        char **f, **t;
+
+        if (!l)
+                return NULL;
+
+        for (f = t = l; *f; f++) {
+
+                if (dir_is_empty(*f) > 0) {
+                        free(*f);
+                        continue;
+                }
+
+                *(t++) = *f;
+        }
+
+        *t = NULL;
+        return l;
+}
+
 int reset_all_signal_handlers(void) {
         int sig;
 
@@ -2241,7 +2261,7 @@ int ask(char *ret, const char *replies, const char *text, ...) {
         }
 }
 
-int reset_terminal(int fd) {
+int reset_terminal_fd(int fd) {
         struct termios termios;
         int r = 0;
         long arg;
@@ -2303,6 +2323,19 @@ finish:
         return r;
 }
 
+int reset_terminal(const char *name) {
+        int fd, r;
+
+        fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC);
+        if (fd < 0)
+                return fd;
+
+        r = reset_terminal_fd(fd);
+        close_nointr_nofail(fd);
+
+        return r;
+}
+
 int open_terminal(const char *name, int mode) {
         int fd, r;
         unsigned c = 0;
@@ -2423,8 +2456,8 @@ int acquire_terminal(const char *name, bool fail, bool force, bool ignore_tiocst
                 /* We pass here O_NOCTTY only so that we can check the return
                  * value TIOCSCTTY and have a reliable way to figure out if we
                  * successfully became the controlling process of the tty */
-                if ((fd = open_terminal(name, O_RDWR|O_NOCTTY)) < 0)
-                        return -errno;
+                if ((fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC)) < 0)
+                        return fd;
 
                 /* First, try to get the tty */
                 r = ioctl(fd, TIOCSCTTY, force);
@@ -2491,7 +2524,7 @@ int acquire_terminal(const char *name, bool fail, bool force, bool ignore_tiocst
         if (notify >= 0)
                 close_nointr_nofail(notify);
 
-        if ((r = reset_terminal(fd)) < 0)
+        if ((r = reset_terminal_fd(fd)) < 0)
                 log_warning("Failed to reset terminal: %s", strerror(-r));
 
         return fd;
@@ -3991,7 +4024,7 @@ int detect_vm(const char **id) {
                 : "0" (eax)
         );
 
-        hypervisor = !!(ecx & ecx & 0x80000000U);
+        hypervisor = !!(ecx & 0x80000000U);
 
         if (hypervisor) {
 
@@ -4393,6 +4426,123 @@ char* hostname_cleanup(char *s) {
         return s;
 }
 
+int terminal_vhangup_fd(int fd) {
+        if (ioctl(fd, TIOCVHANGUP) < 0)
+                return -errno;
+
+        return 0;
+}
+
+int terminal_vhangup(const char *name) {
+        int fd, r;
+
+        fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC);
+        if (fd < 0)
+                return fd;
+
+        r = terminal_vhangup_fd(fd);
+        close_nointr_nofail(fd);
+
+        return r;
+}
+
+int vt_disallocate(const char *name) {
+        int fd, r;
+        unsigned u;
+        int temporary_vt, temporary_fd;
+        char tpath[64];
+        struct vt_stat vt_stat;
+
+        /* Deallocate the VT if possible. If not possible
+         * (i.e. because it is the active one), at least clear it
+         * entirely (including the scrollback buffer) */
+
+        if (!tty_is_vc(name))
+                return -EIO;
+
+        if (!startswith(name, "/dev/tty"))
+                return -EINVAL;
+
+        r = safe_atou(name+8, &u);
+        if (r < 0)
+                return r;
+
+        if (u <= 0)
+                return -EIO;
+
+        fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC);
+        if (fd < 0)
+                return fd;
+
+        r = ioctl(fd, VT_DISALLOCATE, u);
+        if (r >= 0) {
+                close_nointr_nofail(fd);
+                return 0;
+        }
+
+        if (errno != EBUSY) {
+                close_nointr_nofail(fd);
+                return -errno;
+        }
+
+        if (ioctl(fd, VT_GETSTATE, &vt_stat) < 0) {
+                close_nointr_nofail(fd);
+                return -errno;
+        }
+
+        if (u != vt_stat.v_active) {
+                close_nointr_nofail(fd);
+                return -EBUSY;
+        }
+
+        if (ioctl(fd, VT_OPENQRY, &temporary_vt) < 0) {
+                close_nointr_nofail(fd);
+                return -errno;
+        }
+
+        if (temporary_vt <= 0) {
+                close_nointr_nofail(fd);
+                return -EIO;
+        }
+
+        /* Switch to temporary VT */
+        snprintf(tpath, sizeof(tpath), "/dev/tty%i", temporary_vt);
+        char_array_0(tpath);
+        temporary_fd = open_terminal(tpath, O_RDWR|O_NOCTTY|O_CLOEXEC);
+        ioctl(fd, VT_ACTIVATE, temporary_vt);
+        if (temporary_fd >= 0)
+                close_nointr_nofail(temporary_fd);
+
+        /* Reopen /dev/tty0 */
+        close_nointr_nofail(fd);
+        fd = open_terminal("/dev/tty0", O_RDWR|O_NOCTTY|O_CLOEXEC);
+        if (fd < 0)
+                r = -errno;
+        else {
+                /* Disallocate the real VT */
+                if (ioctl(fd, VT_DISALLOCATE, u) < 0)
+                        r = -errno;
+                else
+                        r = 0;
+        }
+
+        /* Recreate original VT */
+        temporary_fd = open_terminal(name, O_RDWR|O_NOCTTY|O_CLOEXEC);
+
+        if (temporary_fd >= 0) {
+                loop_write(temporary_fd, "\033[H\033[2J", 7, false); /* clear screen explicitly */
+                close_nointr_nofail(temporary_fd);
+        }
+
+        /* Switch back to original VT */
+        if (fd >= 0) {
+                ioctl(fd, VT_ACTIVATE, vt_stat.v_active);
+                close_nointr_nofail(fd);
+        }
+
+        return r;
+}
+
 static const char *const ioprio_class_table[] = {
         [IOPRIO_CLASS_NONE] = "none",
         [IOPRIO_CLASS_RT] = "realtime",
@@ -4556,17 +4706,25 @@ static int files_add(Hashmap *h, const char *path, const char *suffix) {
         }
 
         for (de = readdir(dir); de; de = readdir(dir)) {
-                char *f;
+                char *p, *f;
                 const char *base;
 
                 if (!file_is_conf(de, suffix))
                         continue;
 
-                if (asprintf(&f, "%s/%s", path, de->d_name) < 0) {
+                if (asprintf(&p, "%s/%s", path, de->d_name) < 0) {
                         r = -ENOMEM;
                         goto finish;
                 }
 
+                f = canonicalize_file_name(p);
+                if (!f) {
+                        log_error("Failed to canonicalize file name '%s': %m", p);
+                        free(p);
+                        continue;
+                }
+                free(p);
+
                 log_debug("found: %s\n", f);
                 base = f + strlen(path) + 1;
                 if (hashmap_put(h, base, f) <= 0)
@@ -4586,39 +4744,55 @@ static int base_cmp(const void *a, const void *b) {
         return strcmp(file_name_from_path(s1), file_name_from_path(s2));
 }
 
-char **conf_files_list(const char *suffix, const char *dir, ...) {
-        Hashmap *fh;
+int conf_files_list(char ***strv, const char *suffix, const char *dir, ...) {
+        Hashmap *fh = NULL;
+        char **dirs = NULL;
         char **files = NULL;
+        char **p;
         va_list ap;
-        int e = 0;
+        int r = 0;
+
+        va_start(ap, dir);
+        dirs = strv_new_ap(dir, ap);
+        va_end(ap);
+        if (!dirs) {
+                r = -ENOMEM;
+                goto finish;
+        }
+        if (!strv_path_canonicalize(dirs)) {
+                r = -ENOMEM;
+                goto finish;
+        }
+        if (!strv_uniq(dirs)) {
+                r = -ENOMEM;
+                goto finish;
+        }
 
         fh = hashmap_new(string_hash_func, string_compare_func);
         if (!fh) {
-                e = ENOMEM;
+                r = -ENOMEM;
                 goto finish;
         }
 
-        va_start(ap, dir);
-        while (dir) {
-                if (files_add(fh, dir, suffix) < 0) {
+        STRV_FOREACH(p, dirs) {
+                if (files_add(fh, *p, suffix) < 0) {
                         log_error("Failed to search for files.");
-                        e = EINVAL;
+                        r = -EINVAL;
                         goto finish;
                 }
-                dir = va_arg(ap, const char *);
         }
-        va_end(ap);
 
         files = hashmap_get_strv(fh);
         if (files == NULL) {
                 log_error("Failed to compose list of files.");
-                e = ENOMEM;
+                r = -ENOMEM;
                 goto finish;
         }
 
         qsort(files, hashmap_size(fh), sizeof(char *), base_cmp);
 finish:
+        strv_free(dirs);
         hashmap_free(fh);
-        errno = e;
-        return files;
+        *strv = files;
+        return r;
 }