Add instances implementation (still needs testing)

Signed-off-by: Laurent Bercot <ska@appnovation.com>

9 files changed, 283 insertions, 9 deletions

diff --git a/src/instance/deps-exe/s6-instance-control b/src/instance/deps-exe/s6-instance-control
new file mode 100644
index 0000000..e7187fe
--- /dev/null
+++ b/src/instance/deps-exe/s6-instance-control
@@ -0,0 +1 @@
+-lskarnet
diff --git a/src/instance/deps-exe/s6-instance-create b/src/instance/deps-exe/s6-instance-create
new file mode 100644
index 0000000..08815d9
--- /dev/null
+++ b/src/instance/deps-exe/s6-instance-create
@@ -0,0 +1,2 @@
+${LIBS6}
+-lskarnet
diff --git a/src/instance/deps-exe/s6-instance-delete b/src/instance/deps-exe/s6-instance-delete
new file mode 100644
index 0000000..08815d9
--- /dev/null
+++ b/src/instance/deps-exe/s6-instance-delete
@@ -0,0 +1,2 @@
+${LIBS6}
+-lskarnet
diff --git a/src/instance/s6-instance-control.c b/src/instance/s6-instance-control.c
new file mode 100644
index 0000000..899ab89
--- /dev/null
+++ b/src/instance/s6-instance-control.c
@@ -0,0 +1,79 @@
+/* ISC license. */
+
+#include <string.h>
+
+#include <skalibs/bytestr.h>
+#include <skalibs/types.h>
+#include <skalibs/strerr.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/exec.h>
+
+#include <s6/config.h>
+
+#define USAGE "s6-instance-control [ -wu | -wU | -wd | -wD | -wr | -wR ] [ -T timeout ] [ -abqhkti12pcyroduDUxOX ] service instance"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+#define DATASIZE 63
+
+int main (int argc, char const **argv)
+{
+  char const **fullargv = argv ;
+  size_t namelen ;
+  PROG = "s6-instance-control" ;
+
+  {
+    subgetopt l = SUBGETOPT_ZERO ;
+    unsigned int datalen = 1 ;
+    unsigned int timeout = 0 ;
+    for (;;)
+    {
+      int opt = subgetopt_r(argc, argv, "abqhkti12pcyroduxOT:w:", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case 'a' :
+        case 'b' :
+        case 'q' :
+        case 'h' :
+        case 'k' :
+        case 't' :
+        case 'i' :
+        case '1' :
+        case '2' :
+        case 'p' :
+        case 'c' :
+        case 'y' :
+        case 'r' :
+        case 'o' :
+        case 'd' :
+        case 'u' :
+        case 'D' :
+        case 'U' :
+        case 'x' :
+        case 'O' : if (datalen++ >= DATASIZE) strerr_dief1x(100, "too many commands") ; break ;
+        case 'T' : if (!uint0_scan(l.arg, &timeout)) dieusage() ; break ;
+        case 'w' : if (!memchr("dDuUrR", l.arg[0], 6)) dieusage() ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+  }
+
+  if (argc < 2) dieusage() ;
+  namelen = strlen(argv[1]) ;
+  if (!argv[0][0]) strerr_dief1x(100, "invalid service name") ;
+  if (!argv[1][0] || argv[1][0] == '.' || byte_in(argv[1], namelen, " \t\f\r\n", 5) < 5)
+    strerr_dief1x(100, "invalid instance name") ;
+
+  {
+    size_t svlen = strlen(argv[0]) ;
+    char fn[svlen + 11 + namelen] ;
+    memcpy(fn, argv[0], svlen) ;
+    memcpy(fn + svlen, "/instance/", 10) ;
+    memcpy(fn + svlen + 10, argv[1], namelen + 1) ;
+    argv[0] = fn ;
+    argv[1] = 0 ;
+    fullargv[0] = S6_BINPREFIX "s6-svc" ;
+    xexec(fullargv) ;
+  }
+}
diff --git a/src/instance/s6-instance-create.c b/src/instance/s6-instance-create.c
new file mode 100644
index 0000000..2e97618
--- /dev/null
+++ b/src/instance/s6-instance-create.c
@@ -0,0 +1,97 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <skalibs/bytestr.h>
+#include <skalibs/types.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/tai.h>
+#include <skalibs/strerr.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/djbunix.h>
+
+#include <s6/supervise.h>
+
+#define USAGE "s6-instance-create [ -d | -D ] [ -f ] [ -P ] [ -t timeout ] service instancename"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+static inline void checkinstanced (char const *s)  /* chdirs */
+{
+  int fd, r ;
+  size_t len = strlen(s) ;
+  char fn[len + 10] ;
+  memcpy(fn, s, len) ;
+  memcpy(fn + len, "/instance", 10) ;
+  if (chdir(fn) == -1) strerr_diefu2sys(111, "chdir to ", fn) ;
+  fd = open_read(S6_SVSCAN_CTLDIR "/lock") ;
+  if (fd < 0) strerr_diefu3sys(111, "open ", fn, "/" S6_SVSCAN_CTLDIR "/lock") ;
+  r = fd_islocked(fd) ;
+  if (r < 0) strerr_diefu3sys(111, "check lock on ", fn, "/" S6_SVSCAN_CTLDIR "/lock") ;
+  if (!r) strerr_dief2x(1, "instanced service not running on ", s) ;
+  fd_close(fd) ;
+}
+
+static void cleanup (char const *s)
+{
+  int e = errno ;
+  rm_rf(s) ;
+  errno = e ;
+}
+
+int main (int argc, char const *const *argv)
+{
+  tain tto = TAIN_INFINITE_RELATIVE ;
+  size_t namelen ;
+  uint32_t options = 16 ;
+  PROG = "s6-instance-create" ;
+  {
+    unsigned int t = 0 ;
+    subgetopt l = SUBGETOPT_ZERO ;
+    for (;;)
+    {
+      int opt = subgetopt_r(argc, argv, "dDfPt:", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case 'd' : options |= 12 ; break ;
+        case 'D' : options |= 4 ; options &= ~8U ; break ;
+        case 'f' : options |= 1 ; break ;
+        case 'P' : options |= 2 ; break ;
+        case 't' : if (!uint0_scan(l.arg, &t)) dieusage() ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+    if (t) tain_from_millisecs(&tto, t) ;
+  }
+  if (argc < 2) dieusage() ;
+
+  namelen = strlen(argv[1]) ;
+  if (!argv[0][0]) strerr_dief1x(100, "invalid service path") ;
+  if (!argv[1][0] || argv[1][0] == '.' || byte_in(argv[1], namelen, " \t\f\r\n", 5) < 5)
+    strerr_dief1x(100, "invalid instance name") ;
+  checkinstanced(argv[0]) ;
+
+  tain_now_set_stopwatch_g() ;
+  tain_add_g(&tto, &tto) ;
+
+  {
+    char sv[namelen + 14] ;
+    memcpy(sv, "../instances/", 13) ;
+    memcpy(sv + 13, argv[1], namelen + 1) ;
+    if (!hiercopy("../instances/.template", sv))
+    {
+      cleanup(sv) ;
+      strerr_diefu5sys(111, "copy ", argv[0], "/instances/.template to ", argv[0], sv+2) ;
+    }
+    if (s6_supervise_link_names_g(".", (char const *const *)&sv, argv + 1, 1, options, &tto) == -1)
+    {
+      cleanup(sv) ;
+      strerr_diefu4sys(errno == ETIMEDOUT ? 99 : 111, "creatre instance of ", argv[0], " named ", argv[1]) ;
+    }
+  }
+  return 0 ;
+}
diff --git a/src/instance/s6-instance-delete.c b/src/instance/s6-instance-delete.c
new file mode 100644
index 0000000..fc1337a
--- /dev/null
+++ b/src/instance/s6-instance-delete.c
@@ -0,0 +1,61 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <skalibs/bytestr.h>
+#include <skalibs/types.h>
+#include <skalibs/sgetopt.h>
+#include <skalibs/tai.h>
+#include <skalibs/strerr.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/djbunix.h>
+
+#include <s6/supervise.h>
+
+#define USAGE "s6-instance-delete [ -X ] [ -t timeout ] service instancename"
+#define dieusage() strerr_dieusage(100, USAGE)
+
+int main (int argc, char const *const *argv)
+{
+  tain tto = TAIN_INFINITE_RELATIVE ;
+  uint32_t options = 1 ;
+  PROG = "s6-instance-delete" ;
+  {
+    unsigned int t = 0 ;
+    subgetopt l = SUBGETOPT_ZERO ;
+    for (;;)
+    {
+      int opt = subgetopt_r(argc, argv, "Xt:", &l) ;
+      if (opt == -1) break ;
+      switch (opt)
+      {
+        case 'X' : options &= ~1U ; break ;
+        case 't' : if (!uint0_scan(l.arg, &t)) dieusage() ; break ;
+        default : dieusage() ;
+      }
+    }
+    argc -= l.ind ; argv += l.ind ;
+    if (t) tain_from_millisecs(&tto, t) ;
+  }
+  if (argc < 2) dieusage() ;
+  if (!argv[0][0]) strerr_dief1x(100, "invalid service path") ;
+  if (!argv[1][0] || argv[1][0] == '.' || byte_in(argv[1], strlen(argv[1]), " \t\f\r\n", 5) < 5)
+    strerr_dief1x(100, "invalid instance name") ;
+
+  tain_now_set_stopwatch_g() ;
+  tain_add_g(&tto, &tto) ;
+
+  {
+    size_t svlen = strlen(argv[0]) ;
+    char sc[svlen + 10] ;
+    memcpy(sc, argv[0], svlen) ;
+    memcpy(sc + svlen, "/instance", 10) ;
+    if (s6_supervise_unlink_names_g(sc, argv + 1, 1, options, &tto) == -1)
+      strerr_diefu4sys(111, "prepare deletion of instance ", argv[1], " of service ", argv[0]) ;
+  }
+
+  return 0 ;
+}
diff --git a/src/instance/s6-instance-maker.c b/src/instance/s6-instance-maker.c
index 20f557f..e70e569 100644
--- a/src/instance/s6-instance-maker.c
+++ b/src/instance/s6-instance-maker.c
@@ -37,7 +37,7 @@ static int write_run (buffer *b, void *data)
   size_t l ;
   char fmt[UINT_FMT] ;
   l = uint_fmt(fmt, t->maxinstances) ;
-  if (buffer_puts(b, EXECLINE_EXTBINPREFIX "execlineb -S1\n\n"
+  if (buffer_puts(b, EXECLINE_EXTBINPREFIX "execlineb -P\n\n"
     EXECLINE_EXTBINPREFIX "fdmove -c 2 1\n") < 0) return 0 ;
   if (t->user)
   {
diff --git a/src/libs6/s6_supervise_link_names.c b/src/libs6/s6_supervise_link_names.c
index 9af573f..de8e5c5 100644
--- a/src/libs6/s6_supervise_link_names.c
+++ b/src/libs6/s6_supervise_link_names.c
@@ -42,6 +42,7 @@ static uint16_t registerit (ftrigr_t *a, char *fn, size_t len, gid_t gid, uint32
            bit 1: make event/ public
            bit 2: don't start the service
            bit 3: remove down files after starting supervisors
+           bit 4: allow links to relative paths
 */
 
 int s6_supervise_link_names (char const *scdir, char const *const *servicedirs, char const *const *names, size_t n, uint32_t options, tain const *deadline, tain *stamp)
@@ -118,7 +119,7 @@ int s6_supervise_link_names (char const *scdir, char const *const *servicedirs,
       }
       fn[len] = 0 ;
       strcpy(lname + scdirlen + 1, names[i]) ;
-      if (servicedirs[i][0] != '/')
+      if (!(options & 16) && servicedirs[i][0] != '/')
       {
         rpsa.len = 0 ;
         if (sarealpath(&rpsa, servicedirs[i]) < 0 || !stralloc_0(&rpsa)) goto err ;
diff --git a/src/supervision/s6-svc.c b/src/supervision/s6-svc.c
index 7e00f17..5982248 100644
--- a/src/supervision/s6-svc.c
+++ b/src/supervision/s6-svc.c
@@ -7,28 +7,31 @@
 #include <skalibs/types.h>
 #include <skalibs/sgetopt.h>
 #include <skalibs/strerr.h>
+#include <skalibs/djbunix.h>
 #include <skalibs/exec.h>
 
 #include <s6/config.h>
 #include <s6/supervise.h>
 
-#define USAGE "s6-svc [ -wu | -wU | -wd | -wD | -wr | -wR ] [ -T timeout ] [ -abqhkti12pcyroduxOX ] servicedir"
+#define USAGE "s6-svc [ -wu | -wU | -wd | -wD | -wr | -wR ] [ -T timeout ] [ -abqhkti12pcyroduDUxOX ] servicedir"
 #define dieusage() strerr_dieusage(100, USAGE)
 
 #define DATASIZE 63
 
 int main (int argc, char const *const *argv)
 {
-  char data[DATASIZE+1] = "-" ;
+  size_t len ;
+  int downfile = -1 ;
   unsigned int datalen = 1 ;
   unsigned int timeout = 0 ;
+  char data[DATASIZE+1] = "-" ;
   char updown[3] = "-\0" ;
   PROG = "s6-svc" ;
   {
     subgetopt l = SUBGETOPT_ZERO ;
     for (;;)
     {
-      int opt = subgetopt_r(argc, argv, "abqhkti12pcyroduxOT:w:", &l) ;
+      int opt = subgetopt_r(argc, argv, "abqhkti12pcyroduDUxOT:w:", &l) ;
       if (opt == -1) break ;
       switch (opt)
       {
@@ -55,6 +58,20 @@ int main (int argc, char const *const *argv)
           data[datalen++] = opt ;
           break ;
         }
+        case 'D' :
+        {
+          if (datalen >= DATASIZE) strerr_dief1x(100, "too many commands") ;
+          data[datalen++] = 'd' ;
+          downfile = 1 ;
+          break ;
+        }
+        case 'U' :
+        {
+          if (datalen >= DATASIZE) strerr_dief1x(100, "too many commands") ;
+          data[datalen++] = 'u' ;
+          downfile = 0 ;
+          break ;
+        }
         case 'T' : if (!uint0_scan(l.arg, &timeout)) dieusage() ; break ;
         case 'w' :
         {
@@ -69,13 +86,14 @@ int main (int argc, char const *const *argv)
   }
   if (!argc) dieusage() ;
   if (argc > 1) strerr_warnw1x("ignoring extra arguments") ;
+  len = strlen(argv[0]) ;
+  if (!len) strerr_dief1x(100, "invalid service path") ;
 
   if (updown[1] == 'U' || updown[1] == 'R')
   {
-    size_t arglen = strlen(argv[0]) ;
-    char fn[arglen + 17] ;
-    memcpy(fn, argv[0], arglen) ;
-    memcpy(fn + arglen, "/notification-fd", 17) ;
+    char fn[len + 17] ;
+    memcpy(fn, argv[0], len) ;
+    memcpy(fn + len, "/notification-fd", 17) ;
     if (access(fn, F_OK) < 0)
     {
       if (errno != ENOENT) strerr_diefu2sys(111, "access ", fn) ;
@@ -84,6 +102,19 @@ int main (int argc, char const *const *argv)
     }
   }
 
+  if (downfile >= 0)
+  {
+    char fn[len + 6] ;
+    memcpy(fn, argv[0], len) ;
+    memcpy(fn + len, "/down", 6) ;
+    if (downfile)
+    {
+      if (!openwritenclose_unsafe(fn, "", 0))
+        strerr_diefu2sys(111, "touch ", fn) ;
+    }
+    else unlink_void(fn) ;
+  }
+
   if (updown[1])
   {
     char const *newargv[11] ;