Update Android port

* doc/emacs/android.texi (Android Environment): Document lossage
with SIGSTOP.
* exec/exec.c (exec_0): Check X_OK on file being opened.  Also
handle /proc/self/exe.

1 files changed, 46 insertions, 30 deletions

diff --git a/exec/exec.c b/exec/exec.c
index 17051428658..a15386b51bb 100644
--- a/exec/exec.c
+++ b/exec/exec.c
@@ -961,52 +961,68 @@ exec_0 (char *name, struct exec_tracee *tracee,
   ssize_t link_size;
   size_t remaining;
 
-  /* If name is not absolute, then make it relative to TRACEE's
-     cwd.  Use stpcpy, as sprintf is not reentrant.  */
+  /* If the process is trying to run /proc/self/exe, make it run
+     itself instead.  */
 
-  if (name[0] && name[0] != '/')
+  if (!strcmp (name, "/proc/self/exe") && tracee->exec_file)
     {
-      /* Clear `buffer'.  */
-      memset (buffer, 0, sizeof buffer);
-      memset (buffer1, 0, sizeof buffer);
+      strncpy (name, tracee->exec_file, PATH_MAX - 1);
+      name[PATH_MAX] = '\0';
+    }
+  else
+    {
+      /* If name is not absolute, then make it relative to TRACEE's
+         cwd.  Use stpcpy, as sprintf is not reentrant.  */
 
-      /* Copy over /proc, the PID, and /cwd/.  */
-      rewrite = stpcpy (buffer, "/proc/");
-      rewrite = format_pid (rewrite, tracee->pid);
-      stpcpy (rewrite, "/cwd");
+      if (name[0] && name[0] != '/')
+        {
+          /* Clear `buffer'.  */
+          memset (buffer, 0, sizeof buffer);
+          memset (buffer1, 0, sizeof buffer);
 
-      /* Resolve this symbolic link.  */
+          /* Copy over /proc, the PID, and /cwd/.  */
+          rewrite = stpcpy (buffer, "/proc/");
+          rewrite = format_pid (rewrite, tracee->pid);
+          stpcpy (rewrite, "/cwd");
 
-      link_size = readlink (buffer, buffer1,
-                            PATH_MAX + 1);
+          /* Resolve this symbolic link.  */
 
-      if (link_size < 0)
-        return NULL;
+          link_size = readlink (buffer, buffer1,
+                                PATH_MAX + 1);
 
-      /* Check that the name is a reasonable size.  */
+          if (link_size < 0)
+            return NULL;
 
-      if (link_size > PATH_MAX)
-        {
-          /* The name is too long.  */
-          errno = ENAMETOOLONG;
-          return NULL;
-        }
+          /* Check that the name is a reasonable size.  */
+
+          if (link_size > PATH_MAX)
+            {
+              /* The name is too long.  */
+              errno = ENAMETOOLONG;
+              return NULL;
+            }
 
-      /* Add a directory separator if necessary.  */
+          /* Add a directory separator if necessary.  */
       
-      if (!link_size || buffer1[link_size - 1] != '/')
-        buffer1[link_size] = '/', link_size++;
+          if (!link_size || buffer1[link_size - 1] != '/')
+            buffer1[link_size] = '/', link_size++;
 
-      rewrite = buffer1 + link_size;
-      remaining = buffer1 + sizeof buffer1 - rewrite - 1;
-      rewrite = stpncpy (rewrite, name, remaining);
+          rewrite = buffer1 + link_size;
+          remaining = buffer1 + sizeof buffer1 - rewrite - 1;
+          rewrite = stpncpy (rewrite, name, remaining);
 
-      /* Replace name with buffer1.  */
+          /* Replace name with buffer1.  */
 #ifndef REENTRANT
-      strcpy (name, buffer1);
+          strcpy (name, buffer1);
 #endif /* REENTRANT */
+        }
     }
 
+  /* Check that the file is accessible and executable.  */
+
+  if (access (name, X_OK))
+    return NULL;
+
   fd = open (name, O_RDONLY);
   if (fd < 0)
     return NULL;