Do not delete old store before the sync succeeds

7 files changed, 34 insertions, 24 deletions

diff --git a/src/include/s6-rc/repo.h b/src/include/s6-rc/repo.h
index 7122404..5d0426a 100644
--- a/src/include/s6-rc/repo.h
+++ b/src/include/s6-rc/repo.h
@@ -21,7 +21,7 @@ extern int s6rc_repo_sv_bcmpr (void const *a, void const *b, void *aux) ;
 
 extern char const s6rc_repo_subnames[4][7] ;
 
-extern int s6rc_repo_makestores (char const *, char const *const *, uint16_t) ;
+extern int s6rc_repo_makestores (char const *, char const *const *, uint16_t, char *) ;
 
 extern int s6rc_repo_fillset (char const *, char const *, char const *const *, uint32_t) ;
 
diff --git a/src/libs6rc/s6rc_livedir_create.c b/src/libs6rc/s6rc_livedir_create.c
index 0fa4696..7695dfd 100644
--- a/src/libs6rc/s6rc_livedir_create.c
+++ b/src/libs6rc/s6rc_livedir_create.c
@@ -18,17 +18,20 @@ int s6rc_livedir_create (stralloc *sa, char const *live, char const *suffix, cha
 {
   size_t newlen, ddirlen ;
   size_t sabase = sa->len ;
+  mode_t m ;
   int wasnull = !sa->s ;
   if (!s6rc_sanitize_dir(sa, live, &ddirlen)) return 0 ;
   if (!stralloc_cats(sa, ":")) goto err ;
   if (!stralloc_cats(sa, suffix)) goto err ;
   if (!stralloc_cats(sa, ":XXXXXX")) goto err ;
   if (!stralloc_0(sa)) goto err ;
-  if (!mkdtemp(sa->s + sabase)) goto err ;
+  m = umask(0) ;
+  if (!mkdtemp(sa->s + sabase)) { umask(m) ; goto err ; }
   newlen = sa->len-- ;
+  if (!stralloc_catb(sa, "/servicedirs", 13)) { umask(m) ; goto delerr ; }  /* allocates enough for the next strcpys */
+  if (mkdir(sa->s + sabase, 0755) < 0) { umask(m) ; goto delerr ; }
+  umask(m) ;
   if (chmod(sa->s + sabase, 0755) < 0) goto delerr ;
-  if (!stralloc_catb(sa, "/servicedirs", 13)) goto delerr ;  /* allocates enough for the next strcpys */
-  if (mkdir(sa->s + sabase, 0755) < 0) goto delerr ;
   strcpy(sa->s + newlen, "compiled") ;
   if (symlink(compiled, sa->s + sabase) < 0) goto delerr ;
   strcpy(sa->s + newlen, "scandir") ;
diff --git a/src/libs6rc/s6rc_repo_makestores.c b/src/libs6rc/s6rc_repo_makestores.c
index 5568ec5..f61f94c 100644
--- a/src/libs6rc/s6rc_repo_makestores.c
+++ b/src/libs6rc/s6rc_repo_makestores.c
@@ -15,19 +15,17 @@
 
 #include <s6-rc/repo.h>
 
-int s6rc_repo_makestores (char const *repo, char const *const *stores, uint16_t n)
+int s6rc_repo_makestores (char const *repo, char const *const *stores, uint16_t n, char *sold)
 {
   size_t repolen = strlen(repo) ;
   mode_t m = umask(0) ;
   char slink[repolen + 8] ;
   char sdir[repolen + 21] ;
-  char sold[repolen + 16] ;
 
   memcpy(slink, repo, repolen) ;
   memcpy(slink + repolen, "/stores", 8) ;
   memcpy(sdir, slink, repolen + 1) ;
   memcpy(sdir + repolen + 1, ".stores:XXXXXX", 15) ;
-  memcpy(sold, slink, repolen + 1) ;
 
   if (!mkdtemp(sdir))
   {
@@ -54,12 +52,11 @@ int s6rc_repo_makestores (char const *repo, char const *const *stores, uint16_t
     strerr_warnfu2sys("chmod ", sdir) ;
     goto err ;
   }
-  if (!atomic_symlink4(sdir + repolen + 1, slink, sold + repolen + 1, 15))
+  if (!atomic_symlink4(sdir + repolen + 1, slink, sold, 15))
   {
     strerr_warnfu4sys("atomically symlink ", sdir + repolen + 1, " to ", slink) ;
     goto err ;
   }
-  rm_rf(sold) ;
   return 1 ;
 
  err:
diff --git a/src/libs6rc/s6rc_repo_sync.c b/src/libs6rc/s6rc_repo_sync.c
index df462ad..2ec1356 100644
--- a/src/libs6rc/s6rc_repo_sync.c
+++ b/src/libs6rc/s6rc_repo_sync.c
@@ -9,6 +9,7 @@
 #include <errno.h>
 
 #include <skalibs/uint16.h>
+#include <skalibs/stat.h>
 #include <skalibs/direntry.h>
 #include <skalibs/posixplz.h>
 #include <skalibs/strerr.h>
@@ -31,6 +32,7 @@ static inline void cleanup (char const *ato, char const *bun)
 int s6rc_repo_sync (char const *repo, unsigned int verbosity, char const *fdhuser)
 {
   size_t repolen = strlen(repo) ;
+  mode_t m ;
   char store[repolen + 13] ;
   char ato[repolen + 26] ;
   char bun[repolen + 26] ;
@@ -46,14 +48,17 @@ int s6rc_repo_sync (char const *repo, unsigned int verbosity, char const *fdhuse
   memcpy(ato + repolen, "/sources/..atomics:XXXXXX", 26) ;
   memcpy(bun, ato, repolen + 26) ;
   memcpy(bun + repolen + 11, "bundle", 6) ;
+  m = umask(0) ;
   if (!mkdtemp(ato))
   {
     strerr_warnfu2sys("mkdtemp ", ato) ;
+    umask(m) ;
     return 0 ;
   }
   if (chmod(ato, 02755) == -1)
   {
     strerr_warnfu2sys("chmod ", ato) ;
+    umask(m) ;
     return 0 ;
   }
 
@@ -61,8 +66,10 @@ int s6rc_repo_sync (char const *repo, unsigned int verbosity, char const *fdhuse
   {
     strerr_warnfu2sys("mkdtemp ", bun) ;
     rmdir(ato) ;
+    umask(m) ;
     return 0 ;
   }
+  umask(m) ;
   if (chmod(bun, 02755) == -1)
   {
     strerr_warnfu2sys("chmod ", bun) ;
diff --git a/src/libs6rc/s6rc_repo_syncset_tmp.c b/src/libs6rc/s6rc_repo_syncset_tmp.c
index d9bb358..b555bc2 100644
--- a/src/libs6rc/s6rc_repo_syncset_tmp.c
+++ b/src/libs6rc/s6rc_repo_syncset_tmp.c
@@ -1,7 +1,5 @@
 /* ISC license. */
 
-#include <skalibs/nonposix.h>  /* mkdtemp */
-
 #include <string.h>
 #include <stdint.h>
 #include <unistd.h>
diff --git a/src/repo/DESIGN.txt b/src/repo/DESIGN.txt
deleted file mode 100644
index 990e573..0000000
--- a/src/repo/DESIGN.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-
-/var/lib/s6-rc/repository: base
-
-compiled/$name-$stamp
-compiled/$name-current ->
-compiled/$name-previous ->
-
-sources/.everything
-sources/$name -> sources/.$name:XXXXXX
-sources/$name/active
-sources/$name/masked
-sources/$name/onboot
diff --git a/src/repo/s6-rc-repo-init.c b/src/repo/s6-rc-repo-init.c
index b105200..335d83f 100644
--- a/src/repo/s6-rc-repo-init.c
+++ b/src/repo/s6-rc-repo-init.c
@@ -18,6 +18,7 @@
 #include <skalibs/strerr.h>
 #include <skalibs/djbunix.h>
 #include <skalibs/random.h>
+#include <skalibs/unix-transactional.h>
 
 #include <s6-rc/config.h>
 #include <s6-rc/s6rc.h>
@@ -180,13 +181,29 @@ int main (int argc, char const *const *argv)
   if (lockfd == -1)
     strerr_diefu2sys(111, "lock ", wgola[GOLA_REPODIR]) ;
 
-  if (!s6rc_repo_makestores(wgola[GOLA_REPODIR], argv, argc)) _exit(111) ;
+  char sold[repolen + 16] ;
+  memcpy(sold, wgola[GOLA_REPODIR], repolen) ;
+  sold[repolen] = '/' ;
+
+  if (!s6rc_repo_makestores(wgola[GOLA_REPODIR], argv, argc, sold + repolen + 1)) _exit(111) ;
 
   if (!(wgolb & GOLB_BARE))
   {
     if (!s6rc_repo_sync(wgola[GOLA_REPODIR], verbosity, wgola[GOLA_FDHUSER]))
+    {
+      char stores[repolen + 8] ;
+      char snew[repolen + 16] ;
+      memcpy(stores, wgola[GOLA_REPODIR], repolen) ;
+      memcpy(stores + repolen, "/stores", 8) ;
+      memcpy(snew, wgola[GOLA_REPODIR], repolen) ;
+      snew[repolen] = '/' ;
+      if (!atomic_symlink4(sold + repolen + 1, stores, snew + repolen + 1, 15))
+        strerr_diefu7sys(111, "atomically switch back stores at ", wgola[GOLA_REPODIR], " - old store is ", sold + repolen + 1, " and new (invalid) store is ", snew + repolen + 1, " - reported error was") ;
+      rm_rf(snew) ;
       _exit(111) ;
+    }
   }
 
+  rm_rf(sold) ;
   _exit(0) ;
 }