1 files changed, 128 insertions, 0 deletions
diff --git a/src/core/show-status.c b/src/core/show-status.c
new file mode 100644
index 0000000..606237e
--- /dev/null
+++ b/src/core/show-status.c
@@ -0,0 +1,128 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "alloc-util.h"
+#include "fd-util.h"
+#include "iovec-util.h"
+#include "parse-util.h"
+#include "show-status.h"
+#include "string-table.h"
+#include "string-util.h"
+#include "terminal-util.h"
+
+static const char* const show_status_table[_SHOW_STATUS_MAX] = {
+        [SHOW_STATUS_NO]        = "no",
+        [SHOW_STATUS_ERROR]     = "error",
+        [SHOW_STATUS_AUTO]      = "auto",
+        [SHOW_STATUS_TEMPORARY] = "temporary",
+        [SHOW_STATUS_YES]       = "yes",
+};
+
+DEFINE_STRING_TABLE_LOOKUP_WITH_BOOLEAN(show_status, ShowStatus, SHOW_STATUS_YES);
+
+int parse_show_status(const char *v, ShowStatus *ret) {
+        ShowStatus s;
+
+        assert(ret);
+
+        s = show_status_from_string(v);
+        if (s < 0 || s == SHOW_STATUS_TEMPORARY)
+                return -EINVAL;
+
+        *ret = s;
+        return 0;
+}
+
+int status_vprintf(const char *status, ShowStatusFlags flags, const char *format, va_list ap) {
+        static const char status_indent[] = "         "; /* "[" STATUS "] " */
+        _cleanup_free_ char *s = NULL;
+        _cleanup_close_ int fd = -EBADF;
+        struct iovec iovec[7] = {};
+        int n = 0;
+        static bool prev_ephemeral;
+
+        assert(format);
+
+        /* This is independent of logging, as status messages are
+         * optional and go exclusively to the console. */
+
+        if (vasprintf(&s, format, ap) < 0)
+                return log_oom();
+
+        /* Before you ask: yes, on purpose we open/close the console for each status line we write individually. This
+         * is a good strategy to avoid PID 1 getting killed by the kernel's SAK concept (it doesn't fix this entirely,
+         * but minimizes the time window the kernel might end up killing PID 1 due to SAK). It also makes things easier
+         * for us so that we don't have to recover from hangups and suchlike triggered on the console. */
+
+        fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC);
+        if (fd < 0)
+                return fd;
+
+        if (FLAGS_SET(flags, SHOW_STATUS_ELLIPSIZE)) {
+                char *e;
+                size_t emax, sl;
+                int c;
+
+                c = fd_columns(fd);
+                if (c <= 0)
+                        c = 80;
+
+                sl = status ? sizeof(status_indent)-1 : 0;
+
+                emax = c - sl - 1;
+                if (emax < 3)
+                        emax = 3;
+
+                e = ellipsize(s, emax, 50);
+                if (e)
+                        free_and_replace(s, e);
+        }
+
+        if (prev_ephemeral)
+                iovec[n++] = IOVEC_MAKE_STRING(ANSI_REVERSE_LINEFEED "\r" ANSI_ERASE_TO_END_OF_LINE);
+
+        if (status) {
+                if (!isempty(status)) {
+                        iovec[n++] = IOVEC_MAKE_STRING("[");
+                        iovec[n++] = IOVEC_MAKE_STRING(status);
+                        iovec[n++] = IOVEC_MAKE_STRING("] ");
+                } else
+                        iovec[n++] = IOVEC_MAKE_STRING(status_indent);
+        }
+
+        iovec[n++] = IOVEC_MAKE_STRING(s);
+        iovec[n++] = IOVEC_MAKE_STRING("\r\n"); /* use CRNL instead of just NL, to be robust towards TTYs in raw mode */
+
+        if (prev_ephemeral && !FLAGS_SET(flags, SHOW_STATUS_EPHEMERAL))
+                iovec[n++] = IOVEC_MAKE_STRING(ANSI_ERASE_TO_END_OF_LINE);
+        prev_ephemeral = FLAGS_SET(flags, SHOW_STATUS_EPHEMERAL);
+
+        if (writev(fd, iovec, n) < 0)
+                return -errno;
+
+        return 0;
+}
+
+int status_printf(const char *status, ShowStatusFlags flags, const char *format, ...) {
+        va_list ap;
+        int r;
+
+        assert(format);
+
+        va_start(ap, format);
+        r = status_vprintf(status, flags, format, ap);
+        va_end(ap);
+
+        return r;
+}
+
+static const char* const status_unit_format_table[_STATUS_UNIT_FORMAT_MAX] = {
+        [STATUS_UNIT_FORMAT_NAME]        = "name",
+        [STATUS_UNIT_FORMAT_DESCRIPTION] = "description",
+        [STATUS_UNIT_FORMAT_COMBINED]    = "combined",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(status_unit_format, StatusUnitFormat);