Separate socket from pipe in child_spawn. Less code in skaclient!

1 files changed, 125 insertions, 0 deletions

diff --git a/src/libstddjb/child_spawn1_internal.c b/src/libstddjb/child_spawn1_internal.c
new file mode 100644
index 0000000..68b0242
--- /dev/null
+++ b/src/libstddjb/child_spawn1_internal.c
@@ -0,0 +1,125 @@
+/* ISC license. */
+
+#include <skalibs/sysdeps.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <errno.h>
+#include <skalibs/djbunix.h>
+
+#ifdef SKALIBS_HASPOSIXSPAWN
+
+#include <signal.h>
+#include <spawn.h>
+#include <stdlib.h>
+#include <skalibs/config.h>
+#include <skalibs/env.h>
+
+pid_t child_spawn1_internal (char const *prog, char const *const *argv, char const *const *envp, int *p, int to)
+{
+  posix_spawn_file_actions_t actions ;
+  posix_spawnattr_t attr ;
+  int e ;
+  pid_t pid ;
+  int haspath = !!env_get("PATH") ;
+  to = !!to ;
+  if (coe(p[!to]) < 0) { e = errno ; goto err ; }
+  e = posix_spawnattr_init(&attr) ;
+  if (e) goto err ;
+  {
+    sigset_t set ;
+    sigemptyset(&set) ;
+    e = posix_spawnattr_setsigmask(&attr, &set) ;
+  }
+  if (e) goto errattr ;
+  e = posix_spawn_file_actions_init(&actions) ;
+  if (e) goto errattr ;
+  e = posix_spawn_file_actions_addclose(&actions, p[!to]) ;
+  if (e) goto erractions ;
+  e = posix_spawn_file_actions_adddup2(&actions, p[to], to) ;
+  if (e) goto erractions ;
+  if (!haspath && (setenv("PATH", SKALIBS_DEFAULTPATH, 0) < 0)) { e = errno ; goto erractions ; }
+  e = posix_spawnp(&pid, prog, &actions, &attr, (char *const *)argv, (char *const *)envp) ;
+  if (!haspath) unsetenv("PATH") ;
+  posix_spawn_file_actions_destroy(&actions) ;
+  posix_spawnattr_destroy(&attr) ;
+  fd_close(p[to]) ;
+  if (e) goto errp ;
+  return pid ;
+
+ erractions:
+  posix_spawn_file_actions_destroy(&actions) ;
+ errattr:
+  posix_spawnattr_destroy(&attr) ;
+ err:
+  fd_close(p[to]) ;
+ errp:
+  fd_close(p[!to]) ;
+  errno = e ;
+  return 0 ;
+}
+
+#else
+
+#include <skalibs/allreadwrite.h>
+#include <skalibs/sig.h>
+
+pid_t child_spawn1_internal (char const *prog, char const *const *argv, char const *const *envp, int *p, int to)
+{
+  int e ;
+  int syncp[2] ;
+  pid_t pid ;
+  if (coe(p[0]) < 0 || pipecoe(syncp) < 0)
+  {
+    e = errno ;
+    fd_close(p[1]) ;
+    fd_close(p[0]) ;
+    errno = e ;
+    return 0 ;
+  }
+  to = !!to ;
+  pid = fork() ;
+  if (pid < 0)
+  {
+    e = errno ;
+    fd_close(syncp[1]) ;
+    fd_close(syncp[0]) ;
+    fd_close(p[1]) ;
+    fd_close(p[0]) ;
+    errno = e ;
+    return 0 ;
+  }
+  if (pid)
+  {
+    fd_close(syncp[0]) ;
+    fd_close(p[!to]) ;
+    if (fd_move(to, p[to]) < 0) goto err ;
+    sig_blocknone() ;
+    pathexec_run(prog, argv, envp) ;
+err:
+    e = errno ;
+    fd_write(syncp[1], (char *)&e, sizeof(e)) ;
+    _exit(127) ;
+  }
+  fd_close(syncp[1]) ;
+  fd_close(p[to]) ;
+  syncp[1] = fd_read(syncp[0], (char *)&e, sizeof(e)) ;
+  if (syncp[1] < 0)
+  {
+    e = errno ;
+    fd_close(syncp[0]) ;
+    fd_close(p[!to]) ;
+    errno = e ;
+    return 0 ;
+  }
+  fd_close(syncp[0]) ;
+  if (syncp[1] == sizeof(e))
+  {
+    fd_close(p[!to]) ;
+    wait_pid(pid, &syncp[1]) ;
+    errno = e ;
+    return 0 ;
+  }
+  return pid ;
+}
+
+#endif