Convert the string tables to position-independent code.

Author: bhaible

ChangeLog

@@ -1,3 +1,23 @@
+2003-05-22  Bruno Haible  <bruno@clisp.org>
+
+	* lib/genaliases.c (main): Emit %pic instead of %null-strings.
+	Change type of 'name' field to 'int'.
+	* lib/genaliases2.c (emit_encoding): Add a 'tag' argument. Emit an
+	invocation of macro S(), including the tag and a counter.
+	(main): Use the command-line argument as tag.
+	* Makefile.devel (lib/aliases_aix.h, lib/aliases_osf1.h,
+	lib/aliases_dos.h, lib/aliases_extra.h): Pass a tag to the program.
+	* lib/iconv.c (stringpool2_t): New type.
+	(stringpool2_contents): New data table.
+	(stringpool2): New macro.
+	(sysdep_aliases): Make position-independent. Move #includes out to
+	aliases2.h.
+	(aliases2_lookup): Update.
+	(nalias): New type.
+	(compare_by_index): Use 'struct nalias' instead of 'struct alias'.
+	(iconvlist): Convert 'struct alias' to 'struct nalias' while copying.
+	* lib/aliases2.h: New file, extracted from lib/iconv.c.
+
 2003-05-20  Bruno Haible  <bruno@clisp.org>
 
 	* lib/iconv.c (iconvlist): Test p->name against NULL, not against "".

Makefile.devel

@@ -181,22 +181,22 @@ lib/aliases.gperf : lib/encodings.def lib/encodings_local.def lib/genaliases.c
 
 lib/aliases_aix.h : lib/encodings_aix.def lib/genaliases2.c
 	$(CC) $(CFLAGS) -DUSE_AIX lib/genaliases2.c -o genaliases
-	./genaliases > lib/aliases_aix.h
+	./genaliases aix > lib/aliases_aix.h
 	$(RM) genaliases
 
 lib/aliases_osf1.h : lib/encodings_osf1.def lib/genaliases2.c
 	$(CC) $(CFLAGS) -DUSE_OSF1 lib/genaliases2.c -o genaliases
-	./genaliases > lib/aliases_osf1.h
+	./genaliases osf1 > lib/aliases_osf1.h
 	$(RM) genaliases
 
 lib/aliases_dos.h : lib/encodings_dos.def lib/genaliases2.c
 	$(CC) $(CFLAGS) -DUSE_DOS lib/genaliases2.c -o genaliases
-	./genaliases > lib/aliases_dos.h
+	./genaliases dos > lib/aliases_dos.h
 	$(RM) genaliases
 
 lib/aliases_extra.h : lib/encodings_extra.def lib/genaliases2.c
 	$(CC) $(CFLAGS) -DUSE_EXTRA lib/genaliases2.c -o genaliases
-	./genaliases > lib/aliases_extra.h
+	./genaliases extra > lib/aliases_extra.h
 	$(RM) genaliases
 
 

lib/aliases2.h

@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 1999-2003 Free Software Foundation, Inc.
+ * This file is part of the GNU LIBICONV Library.
+ *
+ * The GNU LIBICONV Library is free software; you can redistribute it
+ * and/or modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * The GNU LIBICONV Library is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with the GNU LIBICONV Library; see the file COPYING.LIB.
+ * If not, write to the Free Software Foundation, Inc., 59 Temple Place -
+ * Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifdef USE_AIX
+#include "aliases_aix.h"
+#endif
+#ifdef USE_OSF1
+#include "aliases_osf1.h"
+#endif
+#ifdef USE_DOS
+#include "aliases_dos.h"
+#endif
+#ifdef USE_EXTRA
+#include "aliases_extra.h"
+#endif

lib/genaliases.c

@@ -40,7 +40,7 @@ static void emit_encoding (const char* const* names, size_t n, const char* c_nam
 
 int main ()
 {
-  printf("struct alias { const char* name; unsigned int encoding_index; };\n");
+  printf("struct alias { int name; unsigned int encoding_index; };\n");
   printf("%%struct-type\n");
   printf("%%language=ANSI-C\n");
   printf("%%define hash-function-name aliases_hash\n");
@@ -49,7 +49,7 @@ int main ()
   printf("%%readonly-tables\n");
   printf("%%global-table\n");
   printf("%%define word-array-name aliases\n");
-  printf("%%null-strings\n");
+  printf("%%pic\n");
   printf("%%%%\n");
 
 #define DEFENCODING(xxx_names,xxx,xxx_ifuncs1,xxx_ifuncs2,xxx_ofuncs1,xxx_ofuncs2) \

lib/genaliases2.c

@@ -1,4 +1,4 @@
-/* Copyright (C) 1999-2002 Free Software Foundation, Inc.
+/* Copyright (C) 1999-2003 Free Software Foundation, Inc.
    This file is part of the GNU LIBICONV Library.
 
    The GNU LIBICONV Library is free software; you can redistribute it
@@ -21,10 +21,11 @@
 #include <stdio.h>
 #include <stdlib.h>
 
-static void emit_encoding (const char* const* names, size_t n, const char* c_name)
+static void emit_encoding (const char* tag, const char* const* names, size_t n, const char* c_name)
 {
-  for (; n > 0; names++, n--) {
-    printf("  { \"");
+  static unsigned int counter = 0;
+  for (; n > 0; names++, n--, counter++) {
+    printf("  S(%s_%u, \"",tag,counter);
     /* Output *names in upper case. */
     {
       const char* s = *names;
@@ -37,16 +38,17 @@ static void emit_encoding (const char* const* names, size_t n, const char* c_nam
         putc(c, stdout);
       }
     }
-    printf("\", ei_%s },\n", c_name);
+    printf("\", ei_%s )\n", c_name);
   }
 }
 
-int main ()
+int main (int argc, char* argv[])
 {
+  const char * tag = (argc > 1 ? argv[1] : "xxx");
 #define DEFENCODING(xxx_names,xxx,xxx_ifuncs1,xxx_ifuncs2,xxx_ofuncs1,xxx_ofuncs2) \
   {                                                           \
     static const char* const names[] = BRACIFY xxx_names;     \
-    emit_encoding(names,sizeof(names)/sizeof(names[0]),#xxx); \
+    emit_encoding(tag,names,sizeof(names)/sizeof(names[0]),#xxx); \
   }
 #define BRACIFY(...) { __VA_ARGS__ }
 #ifdef USE_AIX

lib/iconv.c

@@ -132,7 +132,7 @@ static struct encoding const all_encodings[] = {
 /*
  * Alias lookup function.
  * Defines
- *   struct alias { const char* name; unsigned int encoding_index; };
+ *   struct alias { int name; unsigned int encoding_index; };
  *   const struct alias * aliases_lookup (const char *str, unsigned int len);
  *   #define MAX_WORD_LENGTH ...
  */
@@ -144,30 +144,32 @@ static struct encoding const all_encodings[] = {
  *   const struct alias * aliases2_lookup (const char *str);
  */
 #if defined(USE_AIX) || defined(USE_OSF1) || defined(USE_DOS) || defined(USE_EXTRA) /* || ... */
-static struct alias sysdep_aliases[] = {
-#ifdef USE_AIX
-#include "aliases_aix.h"
-#endif
-#ifdef USE_OSF1
-#include "aliases_osf1.h"
-#endif
-#ifdef USE_DOS
-#include "aliases_dos.h"
-#endif
-#ifdef USE_EXTRA
-#include "aliases_extra.h"
-#endif
+struct stringpool2_t {
+#define S(tag,name,encoding_index) char stringpool_##tag[sizeof(name)];
+#include "aliases2.h"
+#undef S
+};
+static const struct stringpool2_t stringpool2_contents = {
+#define S(tag,name,encoding_index) name,
+#include "aliases2.h"
+#undef S
+};
+#define stringpool2 ((const char *) &stringpool2_contents)
+static const struct alias sysdep_aliases[] = {
+#define S(tag,name,encoding_index) { (int)(long)&((struct stringpool2_t *)0)->stringpool_##tag, encoding_index },
+#include "aliases2.h"
+#undef S
 };
 #ifdef __GNUC__
 __inline
 #endif
 const struct alias *
 aliases2_lookup (register const char *str)
 {
-  struct alias * ptr;
+  const struct alias * ptr;
   unsigned int count;
   for (ptr = sysdep_aliases, count = sizeof(sysdep_aliases)/sizeof(sysdep_aliases[0]); count > 0; ptr++, count--)
-    if (!strcmp(str,ptr->name))
+    if (!strcmp(str, stringpool2 + ptr->name))
       return ptr;
   return NULL;
 }
@@ -464,10 +466,13 @@ int iconvctl (iconv_t icd, int request, void* argument)
   }
 }
 
+/* An alias after its name has been converted from 'int' to 'const char*'. */
+struct nalias { const char* name; unsigned int encoding_index; };
+
 static int compare_by_index (const void * arg1, const void * arg2)
 {
-  const struct alias * alias1 = (const struct alias *) arg1;
-  const struct alias * alias2 = (const struct alias *) arg2;
+  const struct nalias * alias1 = (const struct nalias *) arg1;
+  const struct nalias * alias2 = (const struct nalias *) arg2;
   return (int)alias1->encoding_index - (int)alias2->encoding_index;
 }
 
@@ -496,7 +501,7 @@ void iconvlist (int (*do_one) (unsigned int namescount,
 #define aliascount2  0
 #endif
 #define aliascount  (aliascount1+aliascount2)
-  struct alias aliasbuf[aliascount];
+  struct nalias aliasbuf[aliascount];
   const char * namesbuf[aliascount];
   size_t num_aliases;
   {
@@ -506,20 +511,26 @@ void iconvlist (int (*do_one) (unsigned int namescount,
     j = 0;
     for (i = 0; i < aliascount1; i++) {
       const struct alias * p = &aliases[i];
-      if (p->name != NULL
+      if (p->name >= 0
           && p->encoding_index != ei_local_char
-          && p->encoding_index != ei_local_wchar_t)
-        aliasbuf[j++] = *p;
+          && p->encoding_index != ei_local_wchar_t) {
+        aliasbuf[j].name = stringpool + p->name;
+        aliasbuf[j].encoding_index = p->encoding_index;
+        j++;
+      }
     }
 #ifndef aliases2_lookup
-    for (i = 0; i < aliascount2; i++)
-      aliasbuf[j++] = sysdep_aliases[i];
+    for (i = 0; i < aliascount2; i++) {
+      aliasbuf[j].name = stringpool2 + sysdep_aliases[i].name;
+      aliasbuf[j].encoding_index = sysdep_aliases[i].encoding_index;
+      j++;
+    }
 #endif
     num_aliases = j;
   }
   /* Sort by encoding_index. */
   if (num_aliases > 1)
-    qsort(aliasbuf, num_aliases, sizeof(struct alias), compare_by_index);
+    qsort(aliasbuf, num_aliases, sizeof(struct nalias), compare_by_index);
   {
     /* Process all aliases with the same encoding_index together. */
     size_t j;