If user doesn't supply console= in cmdline but instead for example specifies
'stdout-path' in device tree bootlogd fails to detect which tty to use. This
patch brings back methods for detecting current console that were removed in
commit 986bee6.
It also introduces chdir_int helper function used to suppress warnings of
type '-Wunused-result' in findtty().
Signed-off-by: Alexander Vickberg <wickbergs...@gmail.com>
---
src/bootlogd.c | 66 +++++++++++++++++++++++++++++++++++++-------------
1 file changed, 49 insertions(+), 17 deletions(-)
diff --git a/src/bootlogd.c b/src/bootlogd.c
index 10d7c0e..aae66ad 100644
--- a/src/bootlogd.c
+++ b/src/bootlogd.c
@@ -106,12 +106,25 @@ void handler(int sig)
}
/*
- * Scan /dev and find the device name.
+ * chdir with error message on fail.
*/
-/*
-This function does not appear to be called anymore. Commenting it
-out for now, can probably be removed entirely in the future.
+static int chdir_int(const char *path)
+{
+ int ret;
+
+ if ((ret = chdir(path)) != 0) {
+ const char *msgprefix = "bootlogd: %s";
+ char msg[PATH_MAX + sizeof(msgprefix)];
+ snprintf(msg, sizeof(msg), msgprefix, path);
+ perror(msg);
+ }
+
+ return ret;
+}
+/*
+ * Scan /dev and find the device name.
+ */
static int findtty(char *res, const char *startdir, int rlen, dev_t dev)
{
DIR *dir;
@@ -120,13 +133,8 @@ static int findtty(char *res, const char *startdir, int
rlen, dev_t dev)
int r = -1;
char *olddir = getcwd(NULL, 0);
- if (chdir(startdir) < 0 || (dir = opendir(".")) == NULL) {
- int msglen = strlen(startdir) + 11;
- char *msg = malloc(msglen);
- snprintf(msg, msglen, "bootlogd: %s", startdir);
- perror(msg);
- free(msg);
- chdir(olddir);
+ if (chdir_int(startdir) < 0 || (dir = opendir(".")) == NULL) {
+ chdir_int(olddir);
return -1;
}
while ((ent = readdir(dir)) != NULL) {
@@ -141,7 +149,7 @@ static int findtty(char *res, const char *startdir, int
rlen, dev_t dev)
free(path);
if (0 == r) {
closedir(dir);
- chdir(olddir);
+ chdir_int(olddir);
return 0;
}
continue;
@@ -152,22 +160,21 @@ static int findtty(char *res, const char *startdir, int
rlen, dev_t dev)
if ( (int) (strlen(ent->d_name) + strlen(startdir) + 1)
>= rlen) {
fprintf(stderr, "bootlogd: console device name
too long\n");
closedir(dir);
- chdir(olddir);
+ chdir_int(olddir);
return -1;
} else {
snprintf(res, rlen, "%s/%s", startdir,
ent->d_name);
closedir(dir);
- chdir(olddir);
+ chdir_int(olddir);
return 0;
}
}
}
closedir(dir);
- chdir(olddir);
+ chdir_int(olddir);
return r;
}
-*/
/*
* For some reason, openpty() in glibc sometimes doesn't
@@ -269,7 +276,7 @@ int isconsole(char *s, char *res, int rlen)
int consolenames(struct real_cons *cons, int max_consoles)
{
#ifdef TIOCGDEV
- /* This appears to be unused. unsigned int kdev; */
+ unsigned int kdev;
#endif
struct stat st, st2;
char buf[KERNEL_COMMAND_LENGTH];
@@ -340,6 +347,31 @@ dontuse:
p--;
}
+ if (num_consoles > 0) return num_consoles;
+#endif
+
+ fstat(0, &st);
+ if (major(st.st_rdev) != 5 || minor(st.st_rdev) != 1) {
+ /*
+ * Old kernel, can find real device easily.
+ */
+ int r = findtty(cons[num_consoles].name, "/dev",
sizeof(cons[num_consoles].name), st.st_rdev);
+ if (!r)
+ num_consoles++;
+ }
+
+ if (num_consoles > 0) return num_consoles;
+
+#ifdef TIOCGDEV
+# ifndef ENOIOCTLCMD
+# define ENOIOCTLCMD 515
+# endif
+ if (ioctl(0, TIOCGDEV, &kdev) == 0) {
+ int r = findtty(cons[num_consoles].name, "/dev",
sizeof(cons[num_consoles].name), (dev_t)kdev);
+ if (!r)
+ num_consoles++;
+ }
+
if (num_consoles > 0) return num_consoles;
#endif
--
2.25.1
