(EXTRA_DIST): Avoid +=, a GNU make extension.

[bison.git] / src / scan-skel.l

diff --git a/src/scan-skel.l b/src/scan-skel.l
index 71577d7e6aa3281f0655d82989e7bb319dce771f..114407fc06764fc30b7d663fc8106c55e9355d41 100644 (file)
--- a/src/scan-skel.l
+++ b/src/scan-skel.l
@@ -1,6 +1,5 @@
-                                                             /* -*- C -*- */
-/* Scan Bison Skeletons.
-   Copyright (C) 2001  Free Software Foundation, Inc.
+/* Scan Bison Skeletons.                                       -*- C -*-
+   Copyright (C) 2001, 2002  Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -19,63 +18,83 @@
    Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
    02111-1307, USA.  */
 
-%{
+%option nodefault noyywrap nounput never-interactive
+%option prefix="skel_" outfile="lex.yy.c"
 
+%{
 #include "system.h"
-#include "skeleton.h"
-#include "parse-skel.h"
-
+#include "error.h"
+#include "getargs.h"
+#include "files.h"
+int skel_lex PARAMS ((void));
+static int yylineno = 1;
+static char *yyoutname = NULL;
 %}
-
-%option nounput
-%option noyywrap
-/* If we enable
-
-   %option yylineno
-
-   Then we have warning: `yy_flex_realloc' defined but not used.
-   Seems like a Flex bug to me: Why the heck yylineno would trigger
-   the REJECT exception???  */
-
+%%
+  /* This is an approximation, but we don't need more. */
+^"#output \""[^\"]+\"\n        {
+     yytext[yyleng - 2] = '\0';
+     XFREE (yyoutname);
+     yyoutname = xstrdup (yytext + strlen ("#output \""));
+     yyout = xfopen (yyoutname, "w");
+     yylineno = 1;
+   }
+
+"@<:@"           fputc ('[', yyout);
+"@:>@"           fputc (']', yyout);
+
+"__oline__"      fprintf (yyout, "%d", yylineno+1);
+"__ofile__"      fprintf (yyout, "%s", yyoutname);
+[^@_\n]+         ECHO;
+\n+              yylineno += yyleng; ECHO;
+.                ECHO;
+
+<<EOF>>          xfclose (yyout); free (yyoutname); return EOF;
 %%
 
-"%%{line}"          { return LINE; }
-"%%{skeleton-line}" { return SLINE; }
-
-"%%{yacc}"    { return YACC; }
-"%%{section}" { return SECTION; }
-
-"%%{guards}"   { return GUARDS; }
-"%%{actions}"  { return ACTIONS; }
-"%%{tokendef}" { return TOKENS; }
-
-"%%{"[a-zA-Z][0-9a-zA-Z_-]+"}" { /* Muscle.  */
-  size_t len = strlen (yytext);
-  yylval.string = (char*) malloc (len - 3);
-  strncpy (yylval.string, yytext + 3, len - 4);
-  yylval.string[len - 4] = 0;
-  return MUSCLE;
-}
-
-"%%\"".*"\"" { /* String.  */
-  size_t len = strlen (yytext);
-  yylval.string = (char*) malloc (len - 3);
-  strncpy (yylval.string, yytext + 3, len - 4);
-  yylval.string[len - 4] = 0;
-  return STRING;
-}
-
-<<EOF>> { /* End of file.  */
-  return 0;
-}
-
-"\n" { /* End of line.  */
-  return '\n';
-}
-
-. { /* Character.  */
-  yylval.character = *yytext;
-  return CHARACTER;
+/* From lib/readpipe.c.  */
+FILE *readpipe PARAMS ((const char *, ...));
+
+/*----------------------.
+| Run our backend, M4.  |
+`----------------------*/
+
+void m4_invoke PARAMS ((const char *definitions));
+
+void
+m4_invoke (const char *definitions)
+{
+  /* Invoke m4 on the definition of the muscles, and the skeleton. */
+  const char *bison_pkgdatadir = getenv ("BISON_PKGDATADIR");
+  const char *m4 = getenv ("M4");
+  int pkg_data_len;
+  char *full_skeleton;
+
+  if (!m4)
+    m4 = M4;
+  if (!bison_pkgdatadir)
+    bison_pkgdatadir = PKGDATADIR;
+  pkg_data_len = strlen (bison_pkgdatadir);
+  full_skeleton = XMALLOC (char, pkg_data_len + strlen (skeleton) + 2);
+  if (bison_pkgdatadir[pkg_data_len-1] == '/')
+    sprintf (full_skeleton, "%s%s", bison_pkgdatadir, skeleton);
+  else
+    sprintf (full_skeleton, "%s/%s", bison_pkgdatadir, skeleton);
+  if (trace_flag & trace_tools)
+    fprintf (stderr,
+            "running: %s -I %s m4sugar/m4sugar.m4 %s %s\n",
+            m4, bison_pkgdatadir, definitions, full_skeleton);
+  skel_in = readpipe (m4,
+                     "-I", bison_pkgdatadir,
+                     "m4sugar/m4sugar.m4",
+                     definitions,
+                     full_skeleton,
+                     NULL);
+  XFREE (full_skeleton);
+  if (!skel_in)
+    error (EXIT_FAILURE, errno, "cannot run m4");
+  skel_lex ();
+
+  /* Reclaim Flex's buffers.  */
+  yy_delete_buffer (YY_CURRENT_BUFFER);
 }
-
-%%