X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=libiberty%2Fpex-unix.c;h=f9e5277897bf6bd2d4aec0869375932bf568bd27;hb=3061113bf336048d538241282c39baf684de31bf;hp=b9654fca9f8129719006a06c4e38282b2e237123;hpb=b109e79adcb0d7e31737de397f97fa41d1d4e528;p=deliverable%2Fbinutils-gdb.git

diff --git a/libiberty/pex-unix.c b/libiberty/pex-unix.c
index b9654fca9f..f9e5277897 100644
--- a/libiberty/pex-unix.c
+++ b/libiberty/pex-unix.c
@@ -1,8 +1,7 @@
 /* Utilities to execute a program in a subprocess (possibly linked by pipes
    with other subprocesses), and wait for it.  Generic Unix version
    (also used for UWIN and VMS).
-   Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005
-   Free Software Foundation, Inc.
+   Copyright (C) 1996-2019 Free Software Foundation, Inc.
 
 This file is part of the libiberty library.
 Libiberty is free software; you can redistribute it and/or
@@ -17,12 +16,13 @@ Library General Public License for more details.
 
 You should have received a copy of the GNU Library General Public
 License along with libiberty; see the file COPYING.LIB.  If not,
-write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA.  */
+write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
+Boston, MA 02110-1301, USA.  */
 
 #include "config.h"
 #include "libiberty.h"
 #include "pex-common.h"
+#include "environ.h"
 
 #include <stdio.h>
 #include <signal.h>
@@ -55,7 +55,9 @@ extern int errno;
 #ifdef HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif
-
+#ifdef HAVE_PROCESS_H
+#include <process.h>
+#endif
 
 #ifdef vfork /* Autoconf may define this to fork for us. */
 # define VFORK_STRING "fork"
@@ -65,11 +67,42 @@ extern int errno;
 #ifdef HAVE_VFORK_H
 #include <vfork.h>
 #endif
-#ifdef VMS
-#define vfork() (decc$$alloc_vfork_blocks() >= 0 ? \
-               lib$get_current_invo_context(decc$$get_vfork_jmpbuf()) : -1)
-#endif /* VMS */
+#if defined(VMS) && defined (__LONG_POINTERS)
+#ifndef __CHAR_PTR32
+typedef char * __char_ptr32
+__attribute__ ((mode (SI)));
+#endif
+
+typedef __char_ptr32 *__char_ptr_char_ptr32
+__attribute__ ((mode (SI)));
+
+/* Return a 32 bit pointer to an array of 32 bit pointers 
+   given a 64 bit pointer to an array of 64 bit pointers.  */
+
+static __char_ptr_char_ptr32
+to_ptr32 (char **ptr64)
+{
+  int argc;
+  __char_ptr_char_ptr32 short_argv;
+
+  /* Count number of arguments.  */
+  for (argc = 0; ptr64[argc] != NULL; argc++)
+    ;
 
+  /* Reallocate argv with 32 bit pointers.  */
+  short_argv = (__char_ptr_char_ptr32) decc$malloc
+    (sizeof (__char_ptr32) * (argc + 1));
+
+  for (argc = 0; ptr64[argc] != NULL; argc++)
+    short_argv[argc] = (__char_ptr32) decc$strdup (ptr64[argc]);
+
+  short_argv[argc] = (__char_ptr32) 0;
+  return short_argv;
+
+}
+#else
+#define to_ptr32(argv) argv
+#endif
 
 /* File mode to use for private and world-readable files.  */
 
@@ -252,7 +285,7 @@ pex_wait (struct pex_obj *obj, pid_t pid, int *status, struct pex_time *time)
 	  return cpid;
 	}
 
-      psl = xmalloc (sizeof (struct status_list));
+      psl = XNEW (struct status_list);
       psl->pid = cpid;
       psl->status = *status;
       if (time != NULL)
@@ -265,18 +298,18 @@ pex_wait (struct pex_obj *obj, pid_t pid, int *status, struct pex_time *time)
 #endif /* ! defined (HAVE_WAITPID) */
 #endif /* ! defined (HAVE_WAIT4) */
 
-static void pex_child_error (struct pex_obj *, const char *, const char *, int)
-     ATTRIBUTE_NORETURN;
 static int pex_unix_open_read (struct pex_obj *, const char *, int);
-static int pex_unix_open_write (struct pex_obj *, const char *, int);
-static long pex_unix_exec_child (struct pex_obj *, int, const char *,
-				 char * const *, int, int, int,
+static int pex_unix_open_write (struct pex_obj *, const char *, int, int);
+static pid_t pex_unix_exec_child (struct pex_obj *, int, const char *,
+				 char * const *, char * const *,
+				 int, int, int, int,
 				 const char **, int *);
 static int pex_unix_close (struct pex_obj *, int);
-static int pex_unix_wait (struct pex_obj *, long, int *, struct pex_time *,
+static int pex_unix_wait (struct pex_obj *, pid_t, int *, struct pex_time *,
 			  int, const char **, int *);
 static int pex_unix_pipe (struct pex_obj *, int *, int);
 static FILE *pex_unix_fdopenr (struct pex_obj *, int, int);
+static FILE *pex_unix_fdopenw (struct pex_obj *, int, int);
 static void pex_unix_cleanup (struct pex_obj *);
 
 /* The list of functions we pass to the common routines.  */
@@ -290,6 +323,7 @@ const struct pex_funcs funcs =
   pex_unix_wait,
   pex_unix_pipe,
   pex_unix_fdopenr,
+  pex_unix_fdopenw,
   pex_unix_cleanup
 };
 
@@ -314,11 +348,12 @@ pex_unix_open_read (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name,
 
 static int
 pex_unix_open_write (struct pex_obj *obj ATTRIBUTE_UNUSED, const char *name,
-		     int binary ATTRIBUTE_UNUSED)
+		     int binary ATTRIBUTE_UNUSED, int append)
 {
   /* Note that we can't use O_EXCL here because gcc may have already
      created the temporary file via make_temp_file.  */
-  return open (name, O_WRONLY | O_CREAT | O_TRUNC, PUBLIC_MODE);
+  return open (name, O_WRONLY | O_CREAT
+		     | (append ? O_APPEND : O_TRUNC), PUBLIC_MODE);
 }
 
 /* Close a file.  */
@@ -329,40 +364,257 @@ pex_unix_close (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd)
   return close (fd);
 }
 
-/* Report an error from a child process.  We don't use stdio routines,
-   because we might be here due to a vfork call.  */
+/* Execute a child.  */
 
-static void
-pex_child_error (struct pex_obj *obj, const char *executable,
-		 const char *errmsg, int err)
+#if defined(HAVE_SPAWNVE) && defined(HAVE_SPAWNVPE)
+/* Implementation of pex->exec_child using the Cygwin spawn operation.  */
+
+/* Subroutine of pex_unix_exec_child.  Move OLD_FD to a new file descriptor
+   to be stored in *PNEW_FD, save the flags in *PFLAGS, and arrange for the
+   saved copy to be close-on-exec.  Move CHILD_FD into OLD_FD.  If CHILD_FD
+   is -1, OLD_FD is to be closed.  Return -1 on error.  */
+
+static int
+save_and_install_fd(int *pnew_fd, int *pflags, int old_fd, int child_fd)
 {
-#define writeerr(s) write (STDERR_FILE_NO, s, strlen (s))
-  writeerr (obj->pname);
-  writeerr (": error trying to exec '");
-  writeerr (executable);
-  writeerr ("': ");
-  writeerr (errmsg);
-  writeerr (": ");
-  writeerr (xstrerror (err));
-  writeerr ("\n");
-  _exit (-1);
+  int new_fd, flags;
+
+  flags = fcntl (old_fd, F_GETFD);
+
+  /* If we could not retrieve the flags, then OLD_FD was not open.  */
+  if (flags < 0)
+    {
+      new_fd = -1, flags = 0;
+      if (child_fd >= 0 && dup2 (child_fd, old_fd) < 0)
+	return -1;
+    }
+  /* If we wish to close OLD_FD, just mark it CLOEXEC.  */
+  else if (child_fd == -1)
+    {
+      new_fd = old_fd;
+      if ((flags & FD_CLOEXEC) == 0 && fcntl (old_fd, F_SETFD, FD_CLOEXEC) < 0)
+	return -1;
+    }
+  /* Otherwise we need to save a copy of OLD_FD before installing CHILD_FD.  */
+  else
+    {
+#ifdef F_DUPFD_CLOEXEC
+      new_fd = fcntl (old_fd, F_DUPFD_CLOEXEC, 3);
+      if (new_fd < 0)
+	return -1;
+#else
+      /* Prefer F_DUPFD over dup in order to avoid getting a new fd
+	 in the range 0-2, right where a new stderr fd might get put.  */
+      new_fd = fcntl (old_fd, F_DUPFD, 3);
+      if (new_fd < 0)
+	return -1;
+      if (fcntl (new_fd, F_SETFD, FD_CLOEXEC) < 0)
+	return -1;
+#endif
+      if (dup2 (child_fd, old_fd) < 0)
+	return -1;
+    }
+
+  *pflags = flags;
+  if (pnew_fd)
+    *pnew_fd = new_fd;
+  else if (new_fd != old_fd)
+    abort ();
+
+  return 0;
 }
 
-/* Execute a child.  */
+/* Subroutine of pex_unix_exec_child.  Move SAVE_FD back to OLD_FD
+   restoring FLAGS.  If SAVE_FD < 0, OLD_FD is to be closed.  */
 
-static long
-pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable,
-		     char * const * argv, int in, int out, int errdes,
+static int
+restore_fd(int old_fd, int save_fd, int flags)
+{
+  /* For SAVE_FD < 0, all we have to do is restore the
+     "closed-ness" of the original.  */
+  if (save_fd < 0)
+    return close (old_fd);
+
+  /* For SAVE_FD == OLD_FD, all we have to do is restore the
+     original setting of the CLOEXEC flag.  */
+  if (save_fd == old_fd)
+    {
+      if (flags & FD_CLOEXEC)
+	return 0;
+      return fcntl (old_fd, F_SETFD, flags);
+    }
+
+  /* Otherwise we have to move the descriptor back, restore the flags,
+     and close the saved copy.  */
+#ifdef HAVE_DUP3
+  if (flags == FD_CLOEXEC)
+    {
+      if (dup3 (save_fd, old_fd, O_CLOEXEC) < 0)
+	return -1;
+    }
+  else
+#endif
+    {
+      if (dup2 (save_fd, old_fd) < 0)
+	return -1;
+      if (flags != 0 && fcntl (old_fd, F_SETFD, flags) < 0)
+	return -1;
+    }
+  return close (save_fd);
+}
+
+static pid_t
+pex_unix_exec_child (struct pex_obj *obj ATTRIBUTE_UNUSED,
+		     int flags, const char *executable,
+		     char * const * argv, char * const * env,
+                     int in, int out, int errdes, int toclose,
 		     const char **errmsg, int *err)
 {
+  int fl_in = 0, fl_out = 0, fl_err = 0, fl_tc = 0;
+  int save_in = -1, save_out = -1, save_err = -1;
+  int max, retries;
   pid_t pid;
+
+  if (flags & PEX_STDERR_TO_STDOUT)
+    errdes = out;
+
+  /* We need the three standard file descriptors to be set up as for
+     the child before we perform the spawn.  The file descriptors for
+     the parent need to be moved and marked for close-on-exec.  */
+  if (in != STDIN_FILE_NO
+      && save_and_install_fd (&save_in, &fl_in, STDIN_FILE_NO, in) < 0)
+    goto error_dup2;
+  if (out != STDOUT_FILE_NO
+      && save_and_install_fd (&save_out, &fl_out, STDOUT_FILE_NO, out) < 0)
+    goto error_dup2;
+  if (errdes != STDERR_FILE_NO
+      && save_and_install_fd (&save_err, &fl_err, STDERR_FILE_NO, errdes) < 0)
+    goto error_dup2;
+  if (toclose >= 0
+      && save_and_install_fd (NULL, &fl_tc, toclose, -1) < 0)
+    goto error_dup2;
+
+  /* Now that we've moved the file descriptors for the child into place,
+     close the originals.  Be careful not to close any of the standard
+     file descriptors that we just set up.  */
+  max = -1;
+  if (errdes >= 0)
+    max = STDERR_FILE_NO;
+  else if (out >= 0)
+    max = STDOUT_FILE_NO;
+  else if (in >= 0)
+    max = STDIN_FILE_NO;
+  if (in > max)
+    close (in);
+  if (out > max)
+    close (out);
+  if (errdes > max && errdes != out)
+    close (errdes);
+
+  /* If we were not given an environment, use the global environment.  */
+  if (env == NULL)
+    env = environ;
+
+  /* Launch the program.  If we get EAGAIN (normally out of pid's), try
+     again a few times with increasing backoff times.  */
+  retries = 0;
+  while (1)
+    {
+      typedef const char * const *cc_cp;
+
+      if (flags & PEX_SEARCH)
+	pid = spawnvpe (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env);
+      else
+	pid = spawnve (_P_NOWAITO, executable, (cc_cp)argv, (cc_cp)env);
+
+      if (pid > 0)
+	break;
+
+      *err = errno;
+      *errmsg = "spawn";
+      if (errno != EAGAIN || ++retries == 4)
+	return (pid_t) -1;
+      sleep (1 << retries);
+    }
+
+  /* Success.  Restore the parent's file descriptors that we saved above.  */
+  if (toclose >= 0
+      && restore_fd (toclose, toclose, fl_tc) < 0)
+    goto error_dup2;
+  if (in != STDIN_FILE_NO
+      && restore_fd (STDIN_FILE_NO, save_in, fl_in) < 0)
+    goto error_dup2;
+  if (out != STDOUT_FILE_NO
+      && restore_fd (STDOUT_FILE_NO, save_out, fl_out) < 0)
+    goto error_dup2;
+  if (errdes != STDERR_FILE_NO
+      && restore_fd (STDERR_FILE_NO, save_err, fl_err) < 0)
+    goto error_dup2;
+
+  return pid;
+
+ error_dup2:
+  *err = errno;
+  *errmsg = "dup2";
+  return (pid_t) -1;
+}
+
+#else
+/* Implementation of pex->exec_child using standard vfork + exec.  */
+
+static pid_t
+pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable,
+		     char * const * argv, char * const * env,
+                     int in, int out, int errdes,
+		     int toclose, const char **errmsg, int *err)
+{
+  pid_t pid = -1;
+  /* Tuple to communicate error from child to parent.  We can safely
+     transfer string literal pointers as both run with identical
+     address mappings.  */
+  struct fn_err 
+  {
+    const char *fn;
+    int err;
+  };
+  volatile int do_pipe = 0;
+  volatile int pipes[2]; /* [0]:reader,[1]:writer.  */
+#ifdef O_CLOEXEC
+  do_pipe = 1;
+#endif
+  if (do_pipe)
+    {
+#ifdef HAVE_PIPE2
+      if (pipe2 ((int *)pipes, O_CLOEXEC))
+	do_pipe = 0;
+#else
+      if (pipe ((int *)pipes))
+	do_pipe = 0;
+      else
+	{
+	  if (fcntl (pipes[1], F_SETFD, FD_CLOEXEC) == -1)
+	    {
+	      close (pipes[0]);
+	      close (pipes[1]);
+	      do_pipe = 0;
+	    }
+	}
+#endif
+    }
+
   /* We declare these to be volatile to avoid warnings from gcc about
      them being clobbered by vfork.  */
-  volatile int sleep_interval;
+  volatile int sleep_interval = 1;
   volatile int retries;
 
-  sleep_interval = 1;
-  pid = -1;
+  /* We vfork and then set environ in the child before calling execvp.
+     This clobbers the parent's environ so we need to restore it.
+     It would be nice to use one of the exec* functions that takes an
+     environment as a parameter, but that may have portability
+     issues.  It is marked volatile so the child doesn't consider it a
+     dead variable and therefore clobber where ever it is stored.  */
+  char **volatile save_environ = environ;
+
   for (retries = 0; retries < 4; ++retries)
     {
       pid = vfork ();
@@ -375,90 +627,147 @@ pex_unix_exec_child (struct pex_obj *obj, int flags, const char *executable,
   switch (pid)
     {
     case -1:
+      if (do_pipe)
+	{
+	  close (pipes[0]);
+	  close (pipes[1]);
+	}
       *err = errno;
       *errmsg = VFORK_STRING;
-      return -1;
+      return (pid_t) -1;
 
     case 0:
       /* Child process.  */
-      if (in != STDIN_FILE_NO)
-	{
-	  if (dup2 (in, STDIN_FILE_NO) < 0)
-	    pex_child_error (obj, executable, "dup2", errno);
-	  if (close (in) < 0)
-	    pex_child_error (obj, executable, "close", errno);
-	}
-      if (out != STDOUT_FILE_NO)
-	{
-	  if (dup2 (out, STDOUT_FILE_NO) < 0)
-	    pex_child_error (obj, executable, "dup2", errno);
-	  if (close (out) < 0)
-	    pex_child_error (obj, executable, "close", errno);
-	}
-      if (errdes != STDERR_FILE_NO)
-	{
-	  if (dup2 (errdes, STDERR_FILE_NO) < 0)
-	    pex_child_error (obj, executable, "dup2", errno);
-	  if (close (errdes) < 0)
-	    pex_child_error (obj, executable, "close", errno);
-	}
-      if ((flags & PEX_STDERR_TO_STDOUT) != 0)
-	{
-	  if (dup2 (STDOUT_FILE_NO, STDERR_FILE_NO) < 0)
-	    pex_child_error (obj, executable, "dup2", errno);
-	}
-      if ((flags & PEX_SEARCH) != 0)
-	{
-	  execvp (executable, argv);
-	  pex_child_error (obj, executable, "execvp", errno);
-	}
-      else
-	{
-	  execv (executable, argv);
-	  pex_child_error (obj, executable, "execv", errno);
-	}
-
+      {
+	struct fn_err failed;
+	failed.fn = NULL;
+
+	if (do_pipe)
+	  close (pipes[0]);
+	if (!failed.fn && in != STDIN_FILE_NO)
+	  {
+	    if (dup2 (in, STDIN_FILE_NO) < 0)
+	      failed.fn = "dup2", failed.err = errno;
+	    else if (close (in) < 0)
+	      failed.fn = "close", failed.err = errno;
+	  }
+	if (!failed.fn && out != STDOUT_FILE_NO)
+	  {
+	    if (dup2 (out, STDOUT_FILE_NO) < 0)
+	      failed.fn = "dup2", failed.err = errno;
+	    else if (close (out) < 0)
+	      failed.fn = "close", failed.err = errno;
+	  }
+	if (!failed.fn && errdes != STDERR_FILE_NO)
+	  {
+	    if (dup2 (errdes, STDERR_FILE_NO) < 0)
+	      failed.fn = "dup2", failed.err = errno;
+	    else if (close (errdes) < 0)
+	      failed.fn = "close", failed.err = errno;
+	  }
+	if (!failed.fn && toclose >= 0)
+	  {
+	    if (close (toclose) < 0)
+	      failed.fn = "close", failed.err = errno;
+	  }
+	if (!failed.fn && (flags & PEX_STDERR_TO_STDOUT) != 0)
+	  {
+	    if (dup2 (STDOUT_FILE_NO, STDERR_FILE_NO) < 0)
+	      failed.fn = "dup2", failed.err = errno;
+	  }
+	if (!failed.fn)
+	  {
+	    if (env)
+	      /* NOTE: In a standard vfork implementation this clobbers
+		 the parent's copy of environ "too" (in reality there's
+		 only one copy).  This is ok as we restore it below.  */
+	      environ = (char**) env;
+	    if ((flags & PEX_SEARCH) != 0)
+	      {
+		execvp (executable, to_ptr32 (argv));
+		failed.fn = "execvp", failed.err = errno;
+	      }
+	    else
+	      {
+		execv (executable, to_ptr32 (argv));
+		failed.fn = "execv", failed.err = errno;
+	      }
+	  }
+
+	/* Something failed, report an error.  We don't use stdio
+	   routines, because we might be here due to a vfork call.  */
+	ssize_t retval = 0;
+
+	if (!do_pipe
+	    || write (pipes[1], &failed, sizeof (failed)) != sizeof (failed))
+	  {
+	    /* The parent will not see our scream above, so write to
+	       stdout.  */
+#define writeerr(s) (retval |= write (STDERR_FILE_NO, s, strlen (s)))
+	    writeerr (obj->pname);
+	    writeerr (": error trying to exec '");
+	    writeerr (executable);
+	    writeerr ("': ");
+	    writeerr (failed.fn);
+	    writeerr (": ");
+	    writeerr (xstrerror (failed.err));
+	    writeerr ("\n");
+#undef writeerr
+	  }
+
+	/* Exit with -2 if the error output failed, too.  */
+	_exit (retval < 0 ? -2 : -1);
+      }
       /* NOTREACHED */
-      return -1;
+      return (pid_t) -1;
 
     default:
       /* Parent process.  */
-      if (in != STDIN_FILE_NO)
-	{
+      {
+	/* Restore environ.  Note that the parent either doesn't run
+	   until the child execs/exits (standard vfork behaviour), or
+	   if it does run then vfork is behaving more like fork.  In
+	   either case we needn't worry about clobbering the child's
+	   copy of environ.  */
+	environ = save_environ;
+
+	struct fn_err failed;
+	failed.fn = NULL;
+	if (do_pipe)
+	  {
+	    close (pipes[1]);
+	    ssize_t len = read (pipes[0], &failed, sizeof (failed));
+	    if (len < 0)
+	      failed.fn = NULL;
+	    close (pipes[0]);
+	  }
+
+	if (!failed.fn && in != STDIN_FILE_NO)
 	  if (close (in) < 0)
-	    {
-	      *err = errno;
-	      *errmsg = "close";
-	      return -1;
-	    }
-	}
-      if (out != STDOUT_FILE_NO)
-	{
+	    failed.fn = "close", failed.err = errno;
+	if (!failed.fn && out != STDOUT_FILE_NO)
 	  if (close (out) < 0)
-	    {
-	      *err = errno;
-	      *errmsg = "close";
-	      return -1;
-	    }
-	}
-      if (errdes != STDERR_FILE_NO)
-	{
+	    failed.fn = "close", failed.err = errno;
+	if (!failed.fn && errdes != STDERR_FILE_NO)
 	  if (close (errdes) < 0)
-	    {
-	      *err = errno;
-	      *errmsg = "close";
-	      return -1;
-	    }
-	}
-
-      return (long) pid;
+	    failed.fn = "close", failed.err = errno;
+
+	if (failed.fn)
+	  {
+	    *err = failed.err;
+	    *errmsg = failed.fn;
+	    return (pid_t) -1;
+	  }
+      }
+      return pid;
     }
 }
+#endif /* SPAWN */
 
 /* Wait for a child process to complete.  */
 
 static int
-pex_unix_wait (struct pex_obj *obj, long pid, int *status,
+pex_unix_wait (struct pex_obj *obj, pid_t pid, int *status,
 	       struct pex_time *time, int done, const char **errmsg,
 	       int *err)
 {
@@ -495,6 +804,15 @@ pex_unix_fdopenr (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd,
   return fdopen (fd, "r");
 }
 
+static FILE *
+pex_unix_fdopenw (struct pex_obj *obj ATTRIBUTE_UNUSED, int fd,
+		  int binary ATTRIBUTE_UNUSED)
+{
+  if (fcntl (fd, F_SETFD, FD_CLOEXEC) < 0)
+    return NULL;
+  return fdopen (fd, "w");
+}
+
 static void
 pex_unix_cleanup (struct pex_obj *obj ATTRIBUTE_UNUSED)
 {