util: generalize code that checks whether PIDs are alive or unwaited for

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index 3482b9b743b8e1cc7861dcf8c746807cc7dcd6eb..72b1e2f3c89da92c302b10c6f80e3c5940d42f28 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -513,6 +513,31 @@ char *truncate_nl(char *s) {
         return s;
 }
 
+int get_process_state(pid_t pid) {
+        const char *p;
+        char state;
+        int r;
+        _cleanup_free_ char *line = NULL;
+
+        assert(pid >= 0);
+
+        p = procfs_file_alloca(pid, "stat");
+        r = read_one_line_file(p, &line);
+        if (r < 0)
+                return r;
+
+        p = strrchr(line, ')');
+        if (!p)
+                return -EIO;
+
+        p++;
+
+        if (sscanf(p, " %c", &state) != 1)
+                return -EIO;
+
+        return (unsigned char) state;
+}
+
 int get_process_comm(pid_t pid, char **name) {
         const char *p;
         int r;
@@ -2903,24 +2928,6 @@ int status_printf(const char *status, bool ellipse, bool ephemeral, const char *
         return r;
 }
 
-int status_welcome(void) {
-        _cleanup_free_ char *pretty_name = NULL, *ansi_color = NULL;
-        int r;
-
-        r = parse_env_file("/etc/os-release", NEWLINE,
-                           "PRETTY_NAME", &pretty_name,
-                           "ANSI_COLOR", &ansi_color,
-                           NULL);
-
-        if (r < 0 && r != -ENOENT)
-                log_warning("Failed to read /etc/os-release: %s", strerror(-r));
-
-        return status_printf(NULL, false, false,
-                             "\nWelcome to \x1B[%sm%s\x1B[0m!\n",
-                             isempty(ansi_color) ? "1" : ansi_color,
-                             isempty(pretty_name) ? "Linux" : pretty_name);
-}
-
 char *replace_env(const char *format, char **env) {
         enum {
                 WORD,
@@ -5918,6 +5925,35 @@ int proc_cmdline(char **ret) {
         return 1;
 }
 
+int parse_proc_cmdline(int (*parse_word)(const char *word)) {
+        _cleanup_free_ char *line = NULL;
+        char *w, *state;
+        size_t l;
+        int r;
+
+        r = proc_cmdline(&line);
+        if (r < 0)
+                log_warning("Failed to read /proc/cmdline, ignoring: %s", strerror(-r));
+        if (r <= 0)
+                return 0;
+
+        FOREACH_WORD_QUOTED(w, l, line, state) {
+                _cleanup_free_ char *word;
+
+                word = strndup(w, l);
+                if (!word)
+                        return log_oom();
+
+                r = parse_word(word);
+                if (r < 0) {
+                        log_error("Failed on cmdline argument %s: %s", word, strerror(-r));
+                        return r;
+                }
+        }
+
+        return 0;
+}
+
 int container_get_leader(const char *machine, pid_t *pid) {
         _cleanup_free_ char *s = NULL, *class = NULL;
         const char *p;
@@ -6009,7 +6045,9 @@ int namespace_enter(int pidns_fd, int mntns_fd, int root_fd) {
         return 0;
 }
 
-bool pid_valid(pid_t pid) {
+bool pid_is_unwaited(pid_t pid) {
+        /* Checks whether a PID is still valid at all, including a zombie */
+
         if (pid <= 0)
                 return false;
 
@@ -6019,6 +6057,21 @@ bool pid_valid(pid_t pid) {
         return errno != ESRCH;
 }
 
+bool pid_is_alive(pid_t pid) {
+        int r;
+
+        /* Checks whether a PID is still valid and not a zombie */
+
+        if (pid <= 0)
+                return false;
+
+        r = get_process_state(pid);
+        if (r == -ENOENT || r == 'Z')
+                return false;
+
+        return true;
+}
+
 int getpeercred(int fd, struct ucred *ucred) {
         socklen_t n = sizeof(struct ucred);
         struct ucred u;