sulogin: use the linked lists from list.h for consoles list

with this the double linked list feature from util-linux is used
instead of the single linked list.

[kzak@redhat.com: use list_last_entry() and list INIT macros]

Signed-off-by: Werner Fink <werner@suse.de>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/include/consoles.h b/include/consoles.h
index 2283d024b6e89c132afbe160754a93aabd0af690..25442631b7f032ac243ad1eab816102cc3776104 100644 (file)
--- a/include/consoles.h
+++ b/include/consoles.h
@@ -2,6 +2,7 @@
  * consoles.h      Header file for routines to detect the system consoles
  *
  * Copyright (c) 2011 SuSE LINUX Products GmbH, All rights reserved.
+ * Copyright (c) 2012 Werner Fink <werner@suse.de>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -25,6 +26,7 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <termios.h>
+#include <list.h>
 
 struct chardata {
        uint8_t erase;
@@ -33,6 +35,7 @@ struct chardata {
        uint8_t parity;
 };
 struct console {
+       struct list_head entry;
        char *tty;
        FILE *file;
        uint32_t flags;
@@ -42,8 +45,7 @@ struct console {
        pid_t pid;
        struct chardata cp;
        struct termios tio;
-       struct console *next;
 };
 
 extern int detect_consoles(const char *device, int fallback,
-                          struct console **consoles);
+                          struct list_head *consoles);

diff --git a/lib/consoles.c b/lib/consoles.c
index 7bc21b61c9d2e2d6a2e3799058b9f1551c929c16..21c5a249a3ee0aed737821af32a148e8000b3c4b 100644 (file)
--- a/lib/consoles.c
+++ b/lib/consoles.c
@@ -3,6 +3,7 @@
  *
  * Copyright (c) 2011 SuSE LINUX Products GmbH, All rights reserved.
  * Copyright (C) 2012 Karel Zak <kzak@redhat.com>
+ * Copyright (C) 2012 Werner Fink <werner@suse.de>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -56,6 +57,7 @@
 #endif
 
 #define alignof(type)          ((sizeof(type)+(sizeof(void*)-1)) & ~(sizeof(void*)-1))
+#define strsize(string)                (strlen((string))+1)
 
 static int consoles_debug;
 #define DBG(x) do { \
@@ -200,7 +202,7 @@ static
 #ifdef __GNUC__
 __attribute__((__nonnull__,__hot__))
 #endif
-int append_console(struct console **list, char * name)
+int append_console(struct list_head *consoles, const char *name)
 {
        static const struct chardata initcp = {
                .erase  = CERASE,
@@ -209,17 +211,22 @@ int append_console(struct console **list, char * name)
                .parity = 0
        };
        struct console *restrict tail;
-       struct console *last;
+       struct console *last = NULL;
 
        DBG(dbgprint("appenging %s", name));
 
-       if (posix_memalign((void*)&tail, sizeof(void*), alignof(typeof(struct console))) != 0)
+       if (!list_empty(consoles))
+               last = list_last_entry(consoles, struct console, entry);
+
+       if (posix_memalign((void *) &tail, sizeof(void *),
+                          alignof(struct console) + strsize(name)) != 0)
                return -ENOMEM;
 
-       for (last = *list; last && last->next; last = last->next);
+       INIT_LIST_HEAD(&tail->entry);
 
-       tail->next = NULL;
-       tail->tty = name;
+       list_add_tail(&tail->entry, consoles);
+       tail->tty = ((char *) tail) + alignof(struct console);
+       strcpy(tail->tty, name);
 
        tail->file = (FILE*)0;
        tail->flags = 0;
@@ -229,11 +236,6 @@ int append_console(struct console **list, char * name)
        memset(&tail->tio, 0, sizeof(tail->tio));
        memcpy(&tail->cp, &initcp, sizeof(struct chardata));
 
-       if (!last)
-               *list = tail;
-       else
-               last->next = tail;
-
        return 0;
 }
 
@@ -245,7 +247,7 @@ int append_console(struct console **list, char * name)
  *       1     - recoverable error
  *       2     - detection not available
  */
-static int detect_consoles_from_proc(struct console **consoles)
+static int detect_consoles_from_proc(struct list_head *consoles)
 {
        char fbuf[16 + 1];
        DIR *dir = NULL;
@@ -274,11 +276,12 @@ static int detect_consoles_from_proc(struct console **consoles)
                if (!name)
                        continue;
                rc = append_console(consoles, name);
+               free(name);
                if (rc < 0)
                        goto done;
        }
 
-       rc = *consoles ? 0 : 1;
+       rc = list_empty(consoles) ? 1 : 0;
 done:
        if (dir)
                closedir(dir);
@@ -295,7 +298,7 @@ done:
  *       1     - recoverable error
  *       2     - detection not available
  */
-static int detect_consoles_from_sysfs(struct console **consoles)
+static int detect_consoles_from_sysfs(struct list_head *consoles)
 {
        char *attrib = NULL, *words, *token;
        DIR *dir = NULL;
@@ -335,11 +338,12 @@ static int detect_consoles_from_sysfs(struct console **consoles)
                if (!name)
                        continue;
                rc = append_console(consoles, name);
+               free(name);
                if (rc < 0)
                        goto done;
        }
 
-       rc = *consoles ? 0 : 1;
+       rc = list_empty(consoles) ? 1 : 0;
 done:
        free(attrib);
        if (dir)
@@ -349,7 +353,7 @@ done:
 }
 
 
-static int detect_consoles_from_cmdline(struct console **consoles)
+static int detect_consoles_from_cmdline(struct list_head *consoles)
 {
        char *cmdline, *words, *token;
        dev_t comparedev;
@@ -422,11 +426,12 @@ static int detect_consoles_from_cmdline(struct console **consoles)
                if (!name)
                        continue;
                rc = append_console(consoles, name);
+               free(name);
                if (rc < 0)
                        goto done;
        }
 
-       rc = *consoles ? 0 : 1;
+       rc = list_empty(consoles) ? 1 : 0;
 done:
        if (dir)
                closedir(dir);
@@ -435,7 +440,7 @@ done:
        return rc;
 }
 
-static int detect_consoles_from_tiocgdev(struct console **consoles,
+static int detect_consoles_from_tiocgdev(struct list_head *consoles,
                                        int fallback,
                                        const char *device)
 {
@@ -445,6 +450,7 @@ static int detect_consoles_from_tiocgdev(struct console **consoles,
        int rc = 1, fd = -1;
        dev_t comparedev;
        DIR *dir = NULL;
+       struct console *console;
 
        DBG(dbgprint("trying tiocgdev"));
 
@@ -478,12 +484,16 @@ static int detect_consoles_from_tiocgdev(struct console **consoles,
                }
        }
        rc = append_console(consoles, name);
+       free(name);
        if (rc < 0)
                goto done;
-       if (*consoles &&  (!device || !*device))
-               (*consoles)->fd = fallback;
-
-       rc = *consoles ? 0 : 1;
+       if (list_empty(consoles)) {
+               rc = 1;
+               goto done;
+       }
+       console = list_last_entry(consoles, struct console, entry);
+       if (console &&  (!device || !*device))
+               console->fd = fallback;
 done:
        if (fd >= 0)
                close(fd);
@@ -503,7 +513,7 @@ done:
  * Returns 1 if stdout and stderr should be reconnected and 0
  * otherwise or less than zero on error.
  */
-int detect_consoles(const char *device, int fallback, struct console **consoles)
+int detect_consoles(const char *device, int fallback, struct list_head *consoles)
 {
        int fd, reconnect = 0, rc;
        dev_t comparedev = 0;
@@ -581,10 +591,11 @@ int detect_consoles(const char *device, int fallback, struct console **consoles)
 
                if (name) {
                        rc = append_console(consoles, name);
+                       free(name);
                        if (rc < 0)
                                return rc;
                }
-               if (!*consoles)
+               if (list_empty(consoles))
                        goto fallback;
 
                DBG(dbgprint("detection success [rc=%d]", reconnect));
@@ -632,7 +643,7 @@ console:
        if (rc < 0)
                return rc;              /* fatal error */
 
-       if (*consoles) {
+       if (!list_empty(consoles)) {
                DBG(dbgprint("detection success [rc=%d]", reconnect));
                return reconnect;
        }
@@ -642,6 +653,7 @@ console:
 fallback:
        if (fallback >= 0) {
                const char *name;
+               struct console *console;
 
                if (device && *device != '\0')
                        name = device;
@@ -653,8 +665,11 @@ fallback:
                rc = append_console(consoles, strdup(name));
                if (rc < 0)
                        return rc;
-               if (*consoles)
-                       (*consoles)->fd = fallback;
+               if (list_empty(consoles))
+                       return 1;
+               console = list_last_entry(consoles, struct console, entry);
+               if (console)
+                       console->fd = fallback;
        }
 
        DBG(dbgprint("detection done by fallback [rc=%d]", reconnect));
@@ -667,7 +682,8 @@ int main(int argc, char *argv[])
 {
        char *name = NULL;
        int fd, re;
-       struct console *p, *consoles = NULL;
+       LIST_HEAD(consoles);
+       struct list_head *p;
 
        if (argc == 2) {
                name = argv[1];
@@ -682,8 +698,10 @@ int main(int argc, char *argv[])
 
        re = detect_consoles(name, fd, &consoles);
 
-       for (p = consoles; p; p = p->next)
-               printf("%s: id=%d %s\n", p->tty, p->id, re ? "(reconnect) " : "");
+       list_for_each(p, &consoles) {
+               struct console *c = list_entry(p, struct console, entry);
+               printf("%s: id=%d %s\n", c->tty, c->id, re ? "(reconnect) " : "");
+       }
 
        return 0;
 }