manager: optionally print status updates to console on boot

[elogind.git] / src / util.c

diff --git a/src/util.c b/src/util.c
index ea8bfc198457f554b678a41f63f65d44ac3410fa..4795dbcc6aca0358795bafb460ff5a032d58ee04 100644 (file)
--- a/src/util.c
+++ b/src/util.c
@@ -566,6 +566,67 @@ int get_process_name(pid_t pid, char **name) {
         return 0;
 }
 
+int get_process_cmdline(pid_t pid, size_t max_length, char **line) {
+        char *p, *r, *k;
+        int c;
+        bool space = false;
+        size_t left;
+        FILE *f;
+
+        assert(pid >= 1);
+        assert(max_length > 0);
+        assert(line);
+
+        if (asprintf(&p, "/proc/%lu/cmdline", (unsigned long) pid) < 0)
+                return -ENOMEM;
+
+        f = fopen(p, "r");
+        free(p);
+
+        if (!f)
+                return -errno;
+
+        if (!(r = new(char, max_length))) {
+                fclose(f);
+                return -ENOMEM;
+        }
+
+        k = r;
+        left = max_length;
+        while ((c = getc(f)) != EOF) {
+
+                if (isprint(c)) {
+                        if (space) {
+                                if (left <= 4)
+                                        break;
+
+                                *(k++) = ' ';
+                                left--;
+                                space = false;
+                        }
+
+                        if (left <= 4)
+                                break;
+
+                        *(k++) = (char) c;
+                        left--;
+                }  else
+                        space = true;
+        }
+
+        if (left <= 4) {
+                size_t n = MIN(left-1, 3U);
+                memcpy(k, "...", n);
+                k[n] = 0;
+        } else
+                *k = 0;
+
+        fclose(f);
+
+        *line = r;
+        return 0;
+}
+
 char *strappend(const char *s, const char *suffix) {
         size_t a, b;
         char *r;
@@ -2566,6 +2627,30 @@ cpu_set_t* cpu_set_malloc(unsigned *ncpus) {
         }
 }
 
+void status_vprintf(const char *format, va_list ap) {
+        char *s = NULL;
+        int fd = -1;
+
+        assert(format);
+
+        /* This independent of logging, as status messages are
+         * optional and go exclusively to the console. */
+
+        if (vasprintf(&s, format, ap) < 0)
+                goto finish;
+
+        if ((fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0)
+                goto finish;
+
+        write(fd, s, strlen(s));
+
+finish:
+        free(s);
+
+        if (fd >= 0)
+                close_nointr_nofail(fd);
+}
+
 static const char *const ioprio_class_table[] = {
         [IOPRIO_CLASS_NONE] = "none",
         [IOPRIO_CLASS_RT] = "realtime",