[SV 40236] Handle included file open failures properly.

* read.c (eval_makefile): Set deps->error if we discovered any
error reading makefiles, and set NONEXISTENT_MTIME so we know
it needs to be rebuilt.
* main.c (main): Clean up management of makefile_mtimes.
* tests/scripts/features/include: Add open failure testcases.

3 files changed, 53 insertions, 46 deletions

diff --git a/main.c b/main.c
index aa3d80d2..df7bb3af 100644
--- a/main.c
+++ b/main.c
@@ -2150,12 +2150,11 @@ main (int argc, char **argv, char **envp)
   OUTPUT_UNSET ();
   output_close (&make_sync);
 
-  if (read_files != 0)
+  if (read_files)
     {
       /* Update any makefiles if necessary.  */
 
-      FILE_TIMESTAMP *makefile_mtimes = 0;
-      unsigned int mm_idx = 0;
+      FILE_TIMESTAMP *makefile_mtimes;
       char **aargv = NULL;
       const char **nargv;
       int nargc;
@@ -2163,12 +2162,22 @@ main (int argc, char **argv, char **envp)
 
       DB (DB_BASIC, (_("Updating makefiles....\n")));
 
+      {
+        struct goaldep *d;
+        unsigned int num_mkfiles;
+        for (d = read_files; d != NULL; d = d->next)
+          ++num_mkfiles;
+
+        makefile_mtimes = alloca (num_mkfiles * sizeof (FILE_TIMESTAMP));
+      }
+
       /* Remove any makefiles we don't want to try to update.  Record the
          current modtimes of the others so we can compare them later.  */
       {
-        register struct goaldep *d, *last;
-        last = 0;
-        d = read_files;
+        struct goaldep *d = read_files;
+        struct goaldep *last = NULL;
+        unsigned int mm_idx = 0;
+
         while (d != 0)
           {
             struct file *f;
@@ -2202,9 +2211,6 @@ main (int argc, char **argv, char **envp)
               }
             else
               {
-                makefile_mtimes = xrealloc (makefile_mtimes,
-                                            (mm_idx+1)
-                                            * sizeof (FILE_TIMESTAMP));
                 makefile_mtimes[mm_idx++] = file_mtime_no_search (d->file);
                 last = d;
                 d = d->next;
@@ -2453,9 +2459,6 @@ main (int argc, char **argv, char **envp)
           free (aargv);
           break;
         }
-
-      /* Free the makefile mtimes.  */
-      free (makefile_mtimes);
     }
 
   /* Set up 'MAKEFLAGS' again for the normal targets.  */
diff --git a/read.c b/read.c
index 26ba6f9d..047807ae 100644
--- a/read.c
+++ b/read.c
@@ -318,7 +318,11 @@ eval_makefile (const char *filename, int flags)
   struct ebuffer ebuf;
   const floc *curfile;
   char *expanded = 0;
-  int makefile_errno;
+
+  /* Create a new goaldep entry.  */
+  deps = alloc_goaldep ();
+  deps->next = read_files;
+  read_files = deps;
 
   ebuf.floc.filenm = filename; /* Use the original file name.  */
   ebuf.floc.lineno = 1;
@@ -349,13 +353,12 @@ eval_makefile (const char *filename, int flags)
         filename = expanded;
     }
 
+  errno = 0;
   ENULLLOOP (ebuf.fp, fopen (filename, "r"));
-
-  /* Save the error code so we print the right message later.  */
-  makefile_errno = errno;
+  deps->error = errno;
 
   /* Check for unrecoverable errors: out of mem or FILE slots.  */
-  switch (makefile_errno)
+  switch (deps->error)
     {
 #ifdef EMFILE
     case EMFILE:
@@ -365,7 +368,7 @@ eval_makefile (const char *filename, int flags)
 #endif
     case ENOMEM:
       {
-        const char *err = strerror (makefile_errno);
+        const char *err = strerror (deps->error);
         OS (fatal, reading_file, "%s", err);
       }
     }
@@ -389,14 +392,8 @@ eval_makefile (const char *filename, int flags)
         }
     }
 
-  /* Now we have the final name for this makefile. Enter it into
-     the cache.  */
+  /* Enter the final name for this makefile as a goaldep.  */
   filename = strcache_add (filename);
-
-  /* Add FILENAME to the chain of read makefiles.  */
-  deps = alloc_goaldep ();
-  deps->next = read_files;
-  read_files = deps;
   deps->file = lookup_file (filename);
   if (deps->file == 0)
     deps->file = enter_file (filename);
@@ -405,17 +402,19 @@ eval_makefile (const char *filename, int flags)
 
   free (expanded);
 
-  /* If the makefile can't be found at all, give up entirely.  */
-
   if (ebuf.fp == 0)
     {
-      /* If we did some searching, errno has the error from the last
-         attempt, rather from FILENAME itself.  Store it in case the
-         caller wants to use it in a message.  */
-      errno = makefile_errno;
+      /* The makefile can't be read at all, give up entirely.
+         If we did some searching errno has the error from the last attempt,
+         rather from FILENAME itself: recover the more accurate one.  */
+      errno = deps->error;
+      deps->file->last_mtime = NONEXISTENT_MTIME;
       return deps;
     }
 
+  /* Success; clear errno.  */
+  deps->error = 0;
+
   /* Set close-on-exec to avoid leaking the makefile to children, such as
      $(shell ...).  */
 #ifdef HAVE_FILENO
@@ -904,10 +903,7 @@ eval (struct ebuffer *ebuf, int set_default)
               struct goaldep *d = eval_makefile (files->name, flags);
 
               if (errno)
-                {
-                  d->error = (unsigned short)errno;
-                  d->floc = *fstart;
-                }
+                d->floc = *fstart;
 
               free_ns (files);
               files = next;
diff --git a/tests/scripts/features/include b/tests/scripts/features/include
index a21455dd..fe404ad9 100644
--- a/tests/scripts/features/include
+++ b/tests/scripts/features/include
@@ -235,17 +235,25 @@ inc1: foo; echo > $@
 
 rmfiles('inc1');
 
-# include a directory
-
-if ($all_tests) {
-    # Test that include of a rebuild-able file doesn't show a warning
-    # Savannah bug #102
-    run_make_test(q!
-include foo
-foo: ; @echo foo = bar > $@
+# Including files that can't be read should show an error
+create_file('inc1', 'FOO := foo');
+chmod 0000, 'inc1';
+
+run_make_test(q!
+include inc1
+all:;@echo $(FOO)
 !,
-                  '', "#MAKE#: 'foo' is up to date.\n");
-    rmfiles('foo');
-}
+              '', "#MAKEFILE#:2: inc1: $ERR_unreadable_file\n#MAKE#: *** No rule to make target 'inc1'.  Stop.", 512);
+
+# Unreadable files that we know how to successfully recreate should work
+
+run_make_test(sprintf(q!
+all:;@echo $(FOO)
+include inc1
+inc1:; @%s $@ && echo FOO := bar > $@
+!, $CMD_rmfile),
+              '', "bar");
+
+rmfiles('inc1');
 
 1;