Some fixes to the mapfile code.

- Update the comments
- use some defined names instead of magic numbers.
- restore /var/run/mdadm/map to have priority over /dev/.mdadm/map

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/mapfile.c b/mapfile.c
index 8e40b6b7c14cbadf7f0e00c3a53c853ecea2a60e..cc222d295df2ae0c78239f19e399d57a09c06e22 100644 (file)
--- a/mapfile.c
+++ b/mapfile.c
@@ -1,5 +1,5 @@
 /*
- * mapfile - manage /var/run/mdadm.map. Part of:
+ * mapfile - manage /var/run/mdadm/map. Part of:
  * mdadm - manage Linux "md" devices aka RAID arrays.
  *
  * Copyright (C) 2006-2009 Neil Brown <neilb@suse.de>
@@ -28,7 +28,7 @@
  *           Australia
  */
 
-/* /var/run/mdadm.map is used to track arrays being created in --incremental
+/* /var/run/mdadm/map is used to track arrays being created in --incremental
  * mode.  It particularly allows lookup from UUID to array device, but
  * also allows the array device name to be easily found.
  *
@@ -38,12 +38,11 @@
  *  UUID       -  uuid of the array
  *  path       -  path where device created: /dev/md/home
  *
- * The preferred location for the map file is /var/run/mdadm.map.
+ * The preferred location for the map file is /var/run/mdadm/map.
  * However /var/run may not exist or be writable in early boot.  And if
  * no-one has created /var/run/mdadm, we still want to survive.
  * So possible locations are:
- *   /var/run/mdadm/map  /var/run/mdadm.map  /lib/initrw/madam/map
- * The last can easily be change at compile to e.g. somewhere in /dev.
+ *   /var/run/mdadm/map  /dev/.mdadm/map(changable at compile time).
  * We read from the first one that exists and write to the first
  * one that we can.
  */
@@ -51,12 +50,21 @@
 #include       <sys/file.h>
 #include       <ctype.h>
 
-#define mapnames(base) { base, base ".new", base ".lock"}
-char *mapname[2][3] = {
-       mapnames(MAP_DIR "/" MAP_FILE),
-       mapnames("/var/run/mdadm.map")
+#define MAP_READ 0
+#define MAP_NEW 1
+#define MAP_LOCK 2
+#define MAP_DIRNAME 3
+#define mapnames(dir, base) { \
+                       dir "/" base,                           \
+                       dir "/" base ".new",                    \
+                       dir "/" base ".lock",                   \
+                       dir }
+
+#define MAP_DIRS 2
+char *mapname[MAP_DIRS][4] = {
+       mapnames("/var/run/mdadm", "map"),
+       mapnames(MAP_DIR, MAP_FILE),
 };
-char *mapdir[2] = { MAP_DIR, NULL };
 
 int mapmode[3] = { O_RDONLY, O_RDWR|O_CREAT, O_RDWR|O_CREAT|O_TRUNC };
 char *mapsmode[3] = { "r", "w", "w"};
@@ -65,13 +73,13 @@ FILE *open_map(int modenum, int *choice)
 {
        int i;
 
-       for (i = 0 ; i < 2 ; i++) {
+       for (i = 0 ; i <= MAP_DIRS ; i++) {
                int fd;
-               if ((mapmode[modenum] & O_CREAT) && mapdir[i])
+               if ((mapmode[modenum] & O_CREAT))
                        /* Attempt to create directory, don't worry about
                         * failure.
                         */
-                       mkdir(mapdir[i], 0755);
+                       (void)mkdir(mapname[i][MAP_DIRNAME], 0755);
                fd = open(mapname[i][modenum], mapmode[modenum], 0600);
                if (fd >= 0) {
                        *choice = i;
@@ -87,7 +95,7 @@ int map_write(struct map_ent *mel)
        int err;
        int which;
 
-       f = open_map(1, &which);
+       f = open_map(MAP_NEW, &which);
 
        if (!f)
                return 0;
@@ -121,7 +129,7 @@ int map_lock(struct map_ent **melp)
 {
        while (lf == NULL) {
                struct stat buf;
-               lf = open_map(2, &lwhich);
+               lf = open_map(MAP_LOCK, &lwhich);
                if (lf == NULL)
                        return -1;
                if (flock(fileno(lf), LOCK_EX) != 0) {
@@ -184,10 +192,10 @@ void map_read(struct map_ent **melp)
 
        *melp = NULL;
 
-       f = open_map(0, &which);
+       f = open_map(MAP_READ, &which);
        if (!f) {
                RebuildMap();
-               f = open_map(0, &which);
+               f = open_map(MAP_READ, &which);
        }
        if (!f)
                return;