Re: RFC: yacc.c: factor (was: yacc.c does not prototype yyparse in the header)

[Akim Demaille]

Le 12 juin 2012 à 18:24, Akim Demaille a écrit :

> Fourth step.  This introduces a weakness in Bison: when
> given arguments such as
> 
>       --output=sub1/foo.c --defines=sub2/foo.h
> 
> then sub1/foo.c features '#include "sub2/foo.h"'.  But we actually
> already have this problem in glr.c which already prefers to include
> the header instead of duplicating its content.
> 
> So we really need to be able to compute "relative" paths here, to
> be addressed in the near future.
> 
> Ok to install?

I have given a try to computing relative paths by stealing some
bits from the coreutils (relpath.[ch] and a function from ln.c,
as suggested by Eric Blake).  I have pushed in gnulib an akim/relpath
branch with this.

Then I used it in Bison, see below, but I am frighten by the sheer
number of dependencies that this simple idea incurs.  Am I missing
something?  Just have a look at the gitignore changes…
(this is in the declare-yyparse branch of Bison).

Any opinion is *most* welcome.

From 424cb4f460a0f4f1f8325a8eb7e1d0686635962b Mon Sep 17 00:00:00 2001
From: Akim Demaille <address@hidden>
Date: Wed, 13 Jun 2012 22:22:38 +0200
Subject: [PATCH] compute relative paths from parser.c to parser.h for
 #include

* bootstrap.conf: Request relpath.
* gnulib: Update to get it.
* src/scan-skel.l (@relative): New.
* data/glr.c: Use it.
---
 bootstrap.conf  |    2 ++
 data/glr.c      |    2 +-
 gnulib          |    2 +-
 lib/.gitignore  |   47 +++++++++++++++++++++++++++++++++++++++++++++++
 m4/.gitignore   |   25 +++++++++++++++++++++++++
 src/scan-skel.l |   14 ++++++++++++++
 6 files changed, 90 insertions(+), 2 deletions(-)

diff --git a/bootstrap.conf b/bootstrap.conf
index aa05e34..1b68ef5 100644
--- a/bootstrap.conf
+++ b/bootstrap.conf
@@ -28,6 +28,7 @@ gnulib_modules='
   quote quotearg
   readme-release
   realloc-posix
+  relpath
   spawn-pipe stdbool stpcpy strdup-posix strerror strtoul strverscmp
   unistd unistd-safer unlocked-io update-copyright unsetenv verify
   warnings
@@ -42,6 +43,7 @@ XGETTEXT_OPTIONS=$XGETTEXT_OPTIONS'\\\
  --from-code=UTF-8\\\
  --flag=asprintf:2:c-format\\\
  --flag=complain:1:c-format --flag=complain_at:2:c-format\\\
+ --flag=error:3:c-format --flag=error_at_line:5:c-format\\\
  --flag=fatal:1:c-format --flag=fatal_at:2:c-format\\\
  --flag=warn:1:c-format  --flag=warn_at:2:c-format\\\
  --flag=unexpected_end:2:c-format\\\
diff --git a/data/glr.c b/data/glr.c
index 7ebc65c..117ccaa 100644
--- a/data/glr.c
+++ b/data/glr.c
@@ -202,7 +202,7 @@ m4_if(b4_prefix, [yy], [],
 
 ]b4_null_define[
 
-]b4_defines_if([[#include "@basename(]b4_spec_defines_file[@)"]],
+]b4_defines_if([[#include "@relative(]b4_spec_defines_file[@, 
]b4_parser_file_name[@)"]],
               [b4_shared_declarations])[
 
 /* Enabling traces.  */
diff --git a/gnulib b/gnulib
index b42157d..2005fbf 160000
--- a/gnulib
+++ b/gnulib
@@ -1 +1 @@
-Subproject commit b42157dd01e3243646f5a8270c09ee125a8aca21
+Subproject commit 2005fbf739536a0f60bf970c24c1ecf3c9cc8a43
diff --git a/lib/.gitignore b/lib/.gitignore
index 5eec743..bb516bd 100644
--- a/lib/.gitignore
+++ b/lib/.gitignore
@@ -268,3 +268,50 @@
 /xmemdup0.c
 /xmemdup0.h
 /sys_types.in.h
+/relpath.c
+/relpath.h
+/areadlink-with-size.c
+/areadlink.h
+/at-func.c
+/canonicalize.c
+/canonicalize.h
+/chdir-long.c
+/chdir-long.h
+/closedir.c
+/dirent-private.h
+/dirent.in.h
+/dirfd.c
+/dup.c
+/fchdir.c
+/fdopendir.c
+/file-set.c
+/file-set.h
+/filename.h
+/filenamecat-lgpl.c
+/filenamecat.h
+/fstatat.c
+/getcwd-lgpl.c
+/getcwd.c
+/hash-pjw.c
+/hash-pjw.h
+/hash-triple.c
+/hash-triple.h
+/lstat.c
+/mempcpy.c
+/memrchr.c
+/openat-die.c
+/openat-priv.h
+/openat-proc.c
+/openat.c
+/openat.h
+/opendir.c
+/readdir.c
+/readlink.c
+/rewinddir.c
+/same-inode.h
+/same.c
+/same.h
+/save-cwd.c
+/save-cwd.h
+/xgetcwd.c
+/xgetcwd.h
diff --git a/m4/.gitignore b/m4/.gitignore
index d47aee0..d505bf8 100644
--- a/m4/.gitignore
+++ b/m4/.gitignore
@@ -178,3 +178,28 @@
 /xstrndup.m4
 /off_t.m4
 /sys_types_h.m4
+/canonicalize.m4
+/chdir-long.m4
+/closedir.m4
+/d-ino.m4
+/dirent_h.m4
+/dirfd.m4
+/dup.m4
+/fchdir.m4
+/fdopendir.m4
+/filenamecat.m4
+/fstatat.m4
+/getcwd-abort-bug.m4
+/getcwd-path-max.m4
+/getcwd.m4
+/lstat.m4
+/mempcpy.m4
+/memrchr.m4
+/openat.m4
+/opendir.m4
+/readdir.m4
+/readlink.m4
+/rewinddir.m4
+/same.m4
+/save-cwd.m4
+/xgetcwd.m4
diff --git a/src/scan-skel.l b/src/scan-skel.l
index 2433905..7e7f68e 100644
--- a/src/scan-skel.l
+++ b/src/scan-skel.l
@@ -36,6 +36,7 @@
 #include "complain.h"
 #include "getargs.h"
 #include "files.h"
+#include "relpath.h"
 #include "scan-skel.h"
 
 #define YY_DECL static int skel_lex (void)
@@ -265,6 +266,19 @@ at_directive_perform (int at_directive_argc,
             break;
         }
     }
+  else if (0 == strcmp (at_directive_argv[0], "@relative"))
+    {
+      if (at_directive_argc < 3)
+        fail_for_at_directive_too_few_args (at_directive_argv[0]);
+      if (at_directive_argc > 3)
+        fail_for_at_directive_too_many_args (at_directive_argv[0]);
+      {
+       char *rel = convert_abs_rel(at_directive_argv[1],
+                                   at_directive_argv[2]);
+       fputs (rel, yyout);
+       free (rel);
+      }
+    }
   else if (0 == strcmp (at_directive_argv[0], "@output"))
     {
       if (at_directive_argc > 2)
-- 
1.7.10.4