Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / scripts / genksyms / genksyms.c
diff --git a/kernel/scripts/genksyms/genksyms.c b/kernel/scripts/genksyms/genksyms.c
new file mode 100644 (file)
index 0000000..88632df
--- /dev/null
@@ -0,0 +1,875 @@
+/* Generate kernel symbol version hashes.
+   Copyright 1996, 1997 Linux International.
+
+   New implementation contributed by Richard Henderson <rth@tamu.edu>
+   Based on original work by Bjorn Ekwall <bj0rn@blox.se>
+
+   This file was part of the Linux modutils 2.4.22: moved back into the
+   kernel sources by Rusty Russell/Kai Germaschewski.
+
+   This program is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by the
+   Free Software Foundation; either version 2 of the License, or (at your
+   option) any later version.
+
+   This program 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
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <assert.h>
+#include <stdarg.h>
+#ifdef __GNU_LIBRARY__
+#include <getopt.h>
+#endif                         /* __GNU_LIBRARY__ */
+
+#include "genksyms.h"
+/*----------------------------------------------------------------------*/
+
+#define HASH_BUCKETS  4096
+
+static struct symbol *symtab[HASH_BUCKETS];
+static FILE *debugfile;
+
+int cur_line = 1;
+char *cur_filename, *source_file;
+int in_source_file;
+
+static int flag_debug, flag_dump_defs, flag_reference, flag_dump_types,
+          flag_preserve, flag_warnings;
+static const char *mod_prefix = "";
+
+static int errors;
+static int nsyms;
+
+static struct symbol *expansion_trail;
+static struct symbol *visited_symbols;
+
+static const struct {
+       int n;
+       const char *name;
+} symbol_types[] = {
+       [SYM_NORMAL]     = { 0, NULL},
+       [SYM_TYPEDEF]    = {'t', "typedef"},
+       [SYM_ENUM]       = {'e', "enum"},
+       [SYM_STRUCT]     = {'s', "struct"},
+       [SYM_UNION]      = {'u', "union"},
+       [SYM_ENUM_CONST] = {'E', "enum constant"},
+};
+
+static int equal_list(struct string_list *a, struct string_list *b);
+static void print_list(FILE * f, struct string_list *list);
+static struct string_list *concat_list(struct string_list *start, ...);
+static struct string_list *mk_node(const char *string);
+static void print_location(void);
+static void print_type_name(enum symbol_type type, const char *name);
+
+/*----------------------------------------------------------------------*/
+
+static const unsigned int crctab32[] = {
+       0x00000000U, 0x77073096U, 0xee0e612cU, 0x990951baU, 0x076dc419U,
+       0x706af48fU, 0xe963a535U, 0x9e6495a3U, 0x0edb8832U, 0x79dcb8a4U,
+       0xe0d5e91eU, 0x97d2d988U, 0x09b64c2bU, 0x7eb17cbdU, 0xe7b82d07U,
+       0x90bf1d91U, 0x1db71064U, 0x6ab020f2U, 0xf3b97148U, 0x84be41deU,
+       0x1adad47dU, 0x6ddde4ebU, 0xf4d4b551U, 0x83d385c7U, 0x136c9856U,
+       0x646ba8c0U, 0xfd62f97aU, 0x8a65c9ecU, 0x14015c4fU, 0x63066cd9U,
+       0xfa0f3d63U, 0x8d080df5U, 0x3b6e20c8U, 0x4c69105eU, 0xd56041e4U,
+       0xa2677172U, 0x3c03e4d1U, 0x4b04d447U, 0xd20d85fdU, 0xa50ab56bU,
+       0x35b5a8faU, 0x42b2986cU, 0xdbbbc9d6U, 0xacbcf940U, 0x32d86ce3U,
+       0x45df5c75U, 0xdcd60dcfU, 0xabd13d59U, 0x26d930acU, 0x51de003aU,
+       0xc8d75180U, 0xbfd06116U, 0x21b4f4b5U, 0x56b3c423U, 0xcfba9599U,
+       0xb8bda50fU, 0x2802b89eU, 0x5f058808U, 0xc60cd9b2U, 0xb10be924U,
+       0x2f6f7c87U, 0x58684c11U, 0xc1611dabU, 0xb6662d3dU, 0x76dc4190U,
+       0x01db7106U, 0x98d220bcU, 0xefd5102aU, 0x71b18589U, 0x06b6b51fU,
+       0x9fbfe4a5U, 0xe8b8d433U, 0x7807c9a2U, 0x0f00f934U, 0x9609a88eU,
+       0xe10e9818U, 0x7f6a0dbbU, 0x086d3d2dU, 0x91646c97U, 0xe6635c01U,
+       0x6b6b51f4U, 0x1c6c6162U, 0x856530d8U, 0xf262004eU, 0x6c0695edU,
+       0x1b01a57bU, 0x8208f4c1U, 0xf50fc457U, 0x65b0d9c6U, 0x12b7e950U,
+       0x8bbeb8eaU, 0xfcb9887cU, 0x62dd1ddfU, 0x15da2d49U, 0x8cd37cf3U,
+       0xfbd44c65U, 0x4db26158U, 0x3ab551ceU, 0xa3bc0074U, 0xd4bb30e2U,
+       0x4adfa541U, 0x3dd895d7U, 0xa4d1c46dU, 0xd3d6f4fbU, 0x4369e96aU,
+       0x346ed9fcU, 0xad678846U, 0xda60b8d0U, 0x44042d73U, 0x33031de5U,
+       0xaa0a4c5fU, 0xdd0d7cc9U, 0x5005713cU, 0x270241aaU, 0xbe0b1010U,
+       0xc90c2086U, 0x5768b525U, 0x206f85b3U, 0xb966d409U, 0xce61e49fU,
+       0x5edef90eU, 0x29d9c998U, 0xb0d09822U, 0xc7d7a8b4U, 0x59b33d17U,
+       0x2eb40d81U, 0xb7bd5c3bU, 0xc0ba6cadU, 0xedb88320U, 0x9abfb3b6U,
+       0x03b6e20cU, 0x74b1d29aU, 0xead54739U, 0x9dd277afU, 0x04db2615U,
+       0x73dc1683U, 0xe3630b12U, 0x94643b84U, 0x0d6d6a3eU, 0x7a6a5aa8U,
+       0xe40ecf0bU, 0x9309ff9dU, 0x0a00ae27U, 0x7d079eb1U, 0xf00f9344U,
+       0x8708a3d2U, 0x1e01f268U, 0x6906c2feU, 0xf762575dU, 0x806567cbU,
+       0x196c3671U, 0x6e6b06e7U, 0xfed41b76U, 0x89d32be0U, 0x10da7a5aU,
+       0x67dd4accU, 0xf9b9df6fU, 0x8ebeeff9U, 0x17b7be43U, 0x60b08ed5U,
+       0xd6d6a3e8U, 0xa1d1937eU, 0x38d8c2c4U, 0x4fdff252U, 0xd1bb67f1U,
+       0xa6bc5767U, 0x3fb506ddU, 0x48b2364bU, 0xd80d2bdaU, 0xaf0a1b4cU,
+       0x36034af6U, 0x41047a60U, 0xdf60efc3U, 0xa867df55U, 0x316e8eefU,
+       0x4669be79U, 0xcb61b38cU, 0xbc66831aU, 0x256fd2a0U, 0x5268e236U,
+       0xcc0c7795U, 0xbb0b4703U, 0x220216b9U, 0x5505262fU, 0xc5ba3bbeU,
+       0xb2bd0b28U, 0x2bb45a92U, 0x5cb36a04U, 0xc2d7ffa7U, 0xb5d0cf31U,
+       0x2cd99e8bU, 0x5bdeae1dU, 0x9b64c2b0U, 0xec63f226U, 0x756aa39cU,
+       0x026d930aU, 0x9c0906a9U, 0xeb0e363fU, 0x72076785U, 0x05005713U,
+       0x95bf4a82U, 0xe2b87a14U, 0x7bb12baeU, 0x0cb61b38U, 0x92d28e9bU,
+       0xe5d5be0dU, 0x7cdcefb7U, 0x0bdbdf21U, 0x86d3d2d4U, 0xf1d4e242U,
+       0x68ddb3f8U, 0x1fda836eU, 0x81be16cdU, 0xf6b9265bU, 0x6fb077e1U,
+       0x18b74777U, 0x88085ae6U, 0xff0f6a70U, 0x66063bcaU, 0x11010b5cU,
+       0x8f659effU, 0xf862ae69U, 0x616bffd3U, 0x166ccf45U, 0xa00ae278U,
+       0xd70dd2eeU, 0x4e048354U, 0x3903b3c2U, 0xa7672661U, 0xd06016f7U,
+       0x4969474dU, 0x3e6e77dbU, 0xaed16a4aU, 0xd9d65adcU, 0x40df0b66U,
+       0x37d83bf0U, 0xa9bcae53U, 0xdebb9ec5U, 0x47b2cf7fU, 0x30b5ffe9U,
+       0xbdbdf21cU, 0xcabac28aU, 0x53b39330U, 0x24b4a3a6U, 0xbad03605U,
+       0xcdd70693U, 0x54de5729U, 0x23d967bfU, 0xb3667a2eU, 0xc4614ab8U,
+       0x5d681b02U, 0x2a6f2b94U, 0xb40bbe37U, 0xc30c8ea1U, 0x5a05df1bU,
+       0x2d02ef8dU
+};
+
+static unsigned long partial_crc32_one(unsigned char c, unsigned long crc)
+{
+       return crctab32[(crc ^ c) & 0xff] ^ (crc >> 8);
+}
+
+static unsigned long partial_crc32(const char *s, unsigned long crc)
+{
+       while (*s)
+               crc = partial_crc32_one(*s++, crc);
+       return crc;
+}
+
+static unsigned long crc32(const char *s)
+{
+       return partial_crc32(s, 0xffffffff) ^ 0xffffffff;
+}
+
+/*----------------------------------------------------------------------*/
+
+static enum symbol_type map_to_ns(enum symbol_type t)
+{
+       switch (t) {
+       case SYM_ENUM_CONST:
+       case SYM_NORMAL:
+       case SYM_TYPEDEF:
+               return SYM_NORMAL;
+       case SYM_ENUM:
+       case SYM_STRUCT:
+       case SYM_UNION:
+               return SYM_STRUCT;
+       }
+       return t;
+}
+
+struct symbol *find_symbol(const char *name, enum symbol_type ns, int exact)
+{
+       unsigned long h = crc32(name) % HASH_BUCKETS;
+       struct symbol *sym;
+
+       for (sym = symtab[h]; sym; sym = sym->hash_next)
+               if (map_to_ns(sym->type) == map_to_ns(ns) &&
+                   strcmp(name, sym->name) == 0 &&
+                   sym->is_declared)
+                       break;
+
+       if (exact && sym && sym->type != ns)
+               return NULL;
+       return sym;
+}
+
+static int is_unknown_symbol(struct symbol *sym)
+{
+       struct string_list *defn;
+
+       return ((sym->type == SYM_STRUCT ||
+                sym->type == SYM_UNION ||
+                sym->type == SYM_ENUM) &&
+               (defn = sym->defn)  && defn->tag == SYM_NORMAL &&
+                       strcmp(defn->string, "}") == 0 &&
+               (defn = defn->next) && defn->tag == SYM_NORMAL &&
+                       strcmp(defn->string, "UNKNOWN") == 0 &&
+               (defn = defn->next) && defn->tag == SYM_NORMAL &&
+                       strcmp(defn->string, "{") == 0);
+}
+
+static struct symbol *__add_symbol(const char *name, enum symbol_type type,
+                           struct string_list *defn, int is_extern,
+                           int is_reference)
+{
+       unsigned long h;
+       struct symbol *sym;
+       enum symbol_status status = STATUS_UNCHANGED;
+       /* The parser adds symbols in the order their declaration completes,
+        * so it is safe to store the value of the previous enum constant in
+        * a static variable.
+        */
+       static int enum_counter;
+       static struct string_list *last_enum_expr;
+
+       if (type == SYM_ENUM_CONST) {
+               if (defn) {
+                       free_list(last_enum_expr, NULL);
+                       last_enum_expr = copy_list_range(defn, NULL);
+                       enum_counter = 1;
+               } else {
+                       struct string_list *expr;
+                       char buf[20];
+
+                       snprintf(buf, sizeof(buf), "%d", enum_counter++);
+                       if (last_enum_expr) {
+                               expr = copy_list_range(last_enum_expr, NULL);
+                               defn = concat_list(mk_node("("),
+                                                  expr,
+                                                  mk_node(")"),
+                                                  mk_node("+"),
+                                                  mk_node(buf), NULL);
+                       } else {
+                               defn = mk_node(buf);
+                       }
+               }
+       } else if (type == SYM_ENUM) {
+               free_list(last_enum_expr, NULL);
+               last_enum_expr = NULL;
+               enum_counter = 0;
+               if (!name)
+                       /* Anonymous enum definition, nothing more to do */
+                       return NULL;
+       }
+
+       h = crc32(name) % HASH_BUCKETS;
+       for (sym = symtab[h]; sym; sym = sym->hash_next) {
+               if (map_to_ns(sym->type) == map_to_ns(type) &&
+                   strcmp(name, sym->name) == 0) {
+                       if (is_reference)
+                               /* fall through */ ;
+                       else if (sym->type == type &&
+                                equal_list(sym->defn, defn)) {
+                               if (!sym->is_declared && sym->is_override) {
+                                       print_location();
+                                       print_type_name(type, name);
+                                       fprintf(stderr, " modversion is "
+                                               "unchanged\n");
+                               }
+                               sym->is_declared = 1;
+                               return sym;
+                       } else if (!sym->is_declared) {
+                               if (sym->is_override && flag_preserve) {
+                                       print_location();
+                                       fprintf(stderr, "ignoring ");
+                                       print_type_name(type, name);
+                                       fprintf(stderr, " modversion change\n");
+                                       sym->is_declared = 1;
+                                       return sym;
+                               } else {
+                                       status = is_unknown_symbol(sym) ?
+                                               STATUS_DEFINED : STATUS_MODIFIED;
+                               }
+                       } else {
+                               error_with_pos("redefinition of %s", name);
+                               return sym;
+                       }
+                       break;
+               }
+       }
+
+       if (sym) {
+               struct symbol **psym;
+
+               for (psym = &symtab[h]; *psym; psym = &(*psym)->hash_next) {
+                       if (*psym == sym) {
+                               *psym = sym->hash_next;
+                               break;
+                       }
+               }
+               --nsyms;
+       }
+
+       sym = xmalloc(sizeof(*sym));
+       sym->name = name;
+       sym->type = type;
+       sym->defn = defn;
+       sym->expansion_trail = NULL;
+       sym->visited = NULL;
+       sym->is_extern = is_extern;
+
+       sym->hash_next = symtab[h];
+       symtab[h] = sym;
+
+       sym->is_declared = !is_reference;
+       sym->status = status;
+       sym->is_override = 0;
+
+       if (flag_debug) {
+               if (symbol_types[type].name)
+                       fprintf(debugfile, "Defn for %s %s == <",
+                               symbol_types[type].name, name);
+               else
+                       fprintf(debugfile, "Defn for type%d %s == <",
+                               type, name);
+               if (is_extern)
+                       fputs("extern ", debugfile);
+               print_list(debugfile, defn);
+               fputs(">\n", debugfile);
+       }
+
+       ++nsyms;
+       return sym;
+}
+
+struct symbol *add_symbol(const char *name, enum symbol_type type,
+                         struct string_list *defn, int is_extern)
+{
+       return __add_symbol(name, type, defn, is_extern, 0);
+}
+
+static struct symbol *add_reference_symbol(const char *name, enum symbol_type type,
+                                   struct string_list *defn, int is_extern)
+{
+       return __add_symbol(name, type, defn, is_extern, 1);
+}
+
+/*----------------------------------------------------------------------*/
+
+void free_node(struct string_list *node)
+{
+       free(node->string);
+       free(node);
+}
+
+void free_list(struct string_list *s, struct string_list *e)
+{
+       while (s != e) {
+               struct string_list *next = s->next;
+               free_node(s);
+               s = next;
+       }
+}
+
+static struct string_list *mk_node(const char *string)
+{
+       struct string_list *newnode;
+
+       newnode = xmalloc(sizeof(*newnode));
+       newnode->string = xstrdup(string);
+       newnode->tag = SYM_NORMAL;
+       newnode->next = NULL;
+
+       return newnode;
+}
+
+static struct string_list *concat_list(struct string_list *start, ...)
+{
+       va_list ap;
+       struct string_list *n, *n2;
+
+       if (!start)
+               return NULL;
+       for (va_start(ap, start); (n = va_arg(ap, struct string_list *));) {
+               for (n2 = n; n2->next; n2 = n2->next)
+                       ;
+               n2->next = start;
+               start = n;
+       }
+       va_end(ap);
+       return start;
+}
+
+struct string_list *copy_node(struct string_list *node)
+{
+       struct string_list *newnode;
+
+       newnode = xmalloc(sizeof(*newnode));
+       newnode->string = xstrdup(node->string);
+       newnode->tag = node->tag;
+
+       return newnode;
+}
+
+struct string_list *copy_list_range(struct string_list *start,
+                                   struct string_list *end)
+{
+       struct string_list *res, *n;
+
+       if (start == end)
+               return NULL;
+       n = res = copy_node(start);
+       for (start = start->next; start != end; start = start->next) {
+               n->next = copy_node(start);
+               n = n->next;
+       }
+       n->next = NULL;
+       return res;
+}
+
+static int equal_list(struct string_list *a, struct string_list *b)
+{
+       while (a && b) {
+               if (a->tag != b->tag || strcmp(a->string, b->string))
+                       return 0;
+               a = a->next;
+               b = b->next;
+       }
+
+       return !a && !b;
+}
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+static struct string_list *read_node(FILE *f)
+{
+       char buffer[256];
+       struct string_list node = {
+               .string = buffer,
+               .tag = SYM_NORMAL };
+       int c;
+
+       while ((c = fgetc(f)) != EOF) {
+               if (c == ' ') {
+                       if (node.string == buffer)
+                               continue;
+                       break;
+               } else if (c == '\n') {
+                       if (node.string == buffer)
+                               return NULL;
+                       ungetc(c, f);
+                       break;
+               }
+               if (node.string >= buffer + sizeof(buffer) - 1) {
+                       fprintf(stderr, "Token too long\n");
+                       exit(1);
+               }
+               *node.string++ = c;
+       }
+       if (node.string == buffer)
+               return NULL;
+       *node.string = 0;
+       node.string = buffer;
+
+       if (node.string[1] == '#') {
+               size_t n;
+
+               for (n = 0; n < ARRAY_SIZE(symbol_types); n++) {
+                       if (node.string[0] == symbol_types[n].n) {
+                               node.tag = n;
+                               node.string += 2;
+                               return copy_node(&node);
+                       }
+               }
+               fprintf(stderr, "Unknown type %c\n", node.string[0]);
+               exit(1);
+       }
+       return copy_node(&node);
+}
+
+static void read_reference(FILE *f)
+{
+       while (!feof(f)) {
+               struct string_list *defn = NULL;
+               struct string_list *sym, *def;
+               int is_extern = 0, is_override = 0;
+               struct symbol *subsym;
+
+               sym = read_node(f);
+               if (sym && sym->tag == SYM_NORMAL &&
+                   !strcmp(sym->string, "override")) {
+                       is_override = 1;
+                       free_node(sym);
+                       sym = read_node(f);
+               }
+               if (!sym)
+                       continue;
+               def = read_node(f);
+               if (def && def->tag == SYM_NORMAL &&
+                   !strcmp(def->string, "extern")) {
+                       is_extern = 1;
+                       free_node(def);
+                       def = read_node(f);
+               }
+               while (def) {
+                       def->next = defn;
+                       defn = def;
+                       def = read_node(f);
+               }
+               subsym = add_reference_symbol(xstrdup(sym->string), sym->tag,
+                                             defn, is_extern);
+               subsym->is_override = is_override;
+               free_node(sym);
+       }
+}
+
+static void print_node(FILE * f, struct string_list *list)
+{
+       if (symbol_types[list->tag].n) {
+               putc(symbol_types[list->tag].n, f);
+               putc('#', f);
+       }
+       fputs(list->string, f);
+}
+
+static void print_list(FILE * f, struct string_list *list)
+{
+       struct string_list **e, **b;
+       struct string_list *tmp, **tmp2;
+       int elem = 1;
+
+       if (list == NULL) {
+               fputs("(nil)", f);
+               return;
+       }
+
+       tmp = list;
+       while ((tmp = tmp->next) != NULL)
+               elem++;
+
+       b = alloca(elem * sizeof(*e));
+       e = b + elem;
+       tmp2 = e - 1;
+
+       (*tmp2--) = list;
+       while ((list = list->next) != NULL)
+               *(tmp2--) = list;
+
+       while (b != e) {
+               print_node(f, *b++);
+               putc(' ', f);
+       }
+}
+
+static unsigned long expand_and_crc_sym(struct symbol *sym, unsigned long crc)
+{
+       struct string_list *list = sym->defn;
+       struct string_list **e, **b;
+       struct string_list *tmp, **tmp2;
+       int elem = 1;
+
+       if (!list)
+               return crc;
+
+       tmp = list;
+       while ((tmp = tmp->next) != NULL)
+               elem++;
+
+       b = alloca(elem * sizeof(*e));
+       e = b + elem;
+       tmp2 = e - 1;
+
+       *(tmp2--) = list;
+       while ((list = list->next) != NULL)
+               *(tmp2--) = list;
+
+       while (b != e) {
+               struct string_list *cur;
+               struct symbol *subsym;
+
+               cur = *(b++);
+               switch (cur->tag) {
+               case SYM_NORMAL:
+                       if (flag_dump_defs)
+                               fprintf(debugfile, "%s ", cur->string);
+                       crc = partial_crc32(cur->string, crc);
+                       crc = partial_crc32_one(' ', crc);
+                       break;
+
+               case SYM_ENUM_CONST:
+               case SYM_TYPEDEF:
+                       subsym = find_symbol(cur->string, cur->tag, 0);
+                       /* FIXME: Bad reference files can segfault here. */
+                       if (subsym->expansion_trail) {
+                               if (flag_dump_defs)
+                                       fprintf(debugfile, "%s ", cur->string);
+                               crc = partial_crc32(cur->string, crc);
+                               crc = partial_crc32_one(' ', crc);
+                       } else {
+                               subsym->expansion_trail = expansion_trail;
+                               expansion_trail = subsym;
+                               crc = expand_and_crc_sym(subsym, crc);
+                       }
+                       break;
+
+               case SYM_STRUCT:
+               case SYM_UNION:
+               case SYM_ENUM:
+                       subsym = find_symbol(cur->string, cur->tag, 0);
+                       if (!subsym) {
+                               struct string_list *n;
+
+                               error_with_pos("expand undefined %s %s",
+                                              symbol_types[cur->tag].name,
+                                              cur->string);
+                               n = concat_list(mk_node
+                                               (symbol_types[cur->tag].name),
+                                               mk_node(cur->string),
+                                               mk_node("{"),
+                                               mk_node("UNKNOWN"),
+                                               mk_node("}"), NULL);
+                               subsym =
+                                   add_symbol(cur->string, cur->tag, n, 0);
+                       }
+                       if (subsym->expansion_trail) {
+                               if (flag_dump_defs) {
+                                       fprintf(debugfile, "%s %s ",
+                                               symbol_types[cur->tag].name,
+                                               cur->string);
+                               }
+
+                               crc = partial_crc32(symbol_types[cur->tag].name,
+                                                   crc);
+                               crc = partial_crc32_one(' ', crc);
+                               crc = partial_crc32(cur->string, crc);
+                               crc = partial_crc32_one(' ', crc);
+                       } else {
+                               subsym->expansion_trail = expansion_trail;
+                               expansion_trail = subsym;
+                               crc = expand_and_crc_sym(subsym, crc);
+                       }
+                       break;
+               }
+       }
+
+       {
+               static struct symbol **end = &visited_symbols;
+
+               if (!sym->visited) {
+                       *end = sym;
+                       end = &sym->visited;
+                       sym->visited = (struct symbol *)-1L;
+               }
+       }
+
+       return crc;
+}
+
+void export_symbol(const char *name)
+{
+       struct symbol *sym;
+
+       sym = find_symbol(name, SYM_NORMAL, 0);
+       if (!sym)
+               error_with_pos("export undefined symbol %s", name);
+       else {
+               unsigned long crc;
+               int has_changed = 0;
+
+               if (flag_dump_defs)
+                       fprintf(debugfile, "Export %s == <", name);
+
+               expansion_trail = (struct symbol *)-1L;
+
+               sym->expansion_trail = expansion_trail;
+               expansion_trail = sym;
+               crc = expand_and_crc_sym(sym, 0xffffffff) ^ 0xffffffff;
+
+               sym = expansion_trail;
+               while (sym != (struct symbol *)-1L) {
+                       struct symbol *n = sym->expansion_trail;
+
+                       if (sym->status != STATUS_UNCHANGED) {
+                               if (!has_changed) {
+                                       print_location();
+                                       fprintf(stderr, "%s: %s: modversion "
+                                               "changed because of changes "
+                                               "in ", flag_preserve ? "error" :
+                                                      "warning", name);
+                               } else
+                                       fprintf(stderr, ", ");
+                               print_type_name(sym->type, sym->name);
+                               if (sym->status == STATUS_DEFINED)
+                                       fprintf(stderr, " (became defined)");
+                               has_changed = 1;
+                               if (flag_preserve)
+                                       errors++;
+                       }
+                       sym->expansion_trail = 0;
+                       sym = n;
+               }
+               if (has_changed)
+                       fprintf(stderr, "\n");
+
+               if (flag_dump_defs)
+                       fputs(">\n", debugfile);
+
+               /* Used as a linker script. */
+               printf("%s__crc_%s = 0x%08lx ;\n", mod_prefix, name, crc);
+       }
+}
+
+/*----------------------------------------------------------------------*/
+
+static void print_location(void)
+{
+       fprintf(stderr, "%s:%d: ", cur_filename ? : "<stdin>", cur_line);
+}
+
+static void print_type_name(enum symbol_type type, const char *name)
+{
+       if (symbol_types[type].name)
+               fprintf(stderr, "%s %s", symbol_types[type].name, name);
+       else
+               fprintf(stderr, "%s", name);
+}
+
+void error_with_pos(const char *fmt, ...)
+{
+       va_list args;
+
+       if (flag_warnings) {
+               print_location();
+
+               va_start(args, fmt);
+               vfprintf(stderr, fmt, args);
+               va_end(args);
+               putc('\n', stderr);
+
+               errors++;
+       }
+}
+
+static void genksyms_usage(void)
+{
+       fputs("Usage:\n" "genksyms [-adDTwqhV] > /path/to/.tmp_obj.ver\n" "\n"
+#ifdef __GNU_LIBRARY__
+             "  -s, --symbol-prefix   Select symbol prefix\n"
+             "  -d, --debug           Increment the debug level (repeatable)\n"
+             "  -D, --dump            Dump expanded symbol defs (for debugging only)\n"
+             "  -r, --reference file  Read reference symbols from a file\n"
+             "  -T, --dump-types file Dump expanded types into file\n"
+             "  -p, --preserve        Preserve reference modversions or fail\n"
+             "  -w, --warnings        Enable warnings\n"
+             "  -q, --quiet           Disable warnings (default)\n"
+             "  -h, --help            Print this message\n"
+             "  -V, --version         Print the release version\n"
+#else                          /* __GNU_LIBRARY__ */
+             "  -s                    Select symbol prefix\n"
+             "  -d                    Increment the debug level (repeatable)\n"
+             "  -D                    Dump expanded symbol defs (for debugging only)\n"
+             "  -r file               Read reference symbols from a file\n"
+             "  -T file               Dump expanded types into file\n"
+             "  -p                    Preserve reference modversions or fail\n"
+             "  -w                    Enable warnings\n"
+             "  -q                    Disable warnings (default)\n"
+             "  -h                    Print this message\n"
+             "  -V                    Print the release version\n"
+#endif                         /* __GNU_LIBRARY__ */
+             , stderr);
+}
+
+int main(int argc, char **argv)
+{
+       FILE *dumpfile = NULL, *ref_file = NULL;
+       int o;
+
+#ifdef __GNU_LIBRARY__
+       struct option long_opts[] = {
+               {"symbol-prefix", 1, 0, 's'},
+               {"debug", 0, 0, 'd'},
+               {"warnings", 0, 0, 'w'},
+               {"quiet", 0, 0, 'q'},
+               {"dump", 0, 0, 'D'},
+               {"reference", 1, 0, 'r'},
+               {"dump-types", 1, 0, 'T'},
+               {"preserve", 0, 0, 'p'},
+               {"version", 0, 0, 'V'},
+               {"help", 0, 0, 'h'},
+               {0, 0, 0, 0}
+       };
+
+       while ((o = getopt_long(argc, argv, "s:dwqVDr:T:ph",
+                               &long_opts[0], NULL)) != EOF)
+#else                          /* __GNU_LIBRARY__ */
+       while ((o = getopt(argc, argv, "s:dwqVDr:T:ph")) != EOF)
+#endif                         /* __GNU_LIBRARY__ */
+               switch (o) {
+               case 's':
+                       mod_prefix = optarg;
+                       break;
+               case 'd':
+                       flag_debug++;
+                       break;
+               case 'w':
+                       flag_warnings = 1;
+                       break;
+               case 'q':
+                       flag_warnings = 0;
+                       break;
+               case 'V':
+                       fputs("genksyms version 2.5.60\n", stderr);
+                       break;
+               case 'D':
+                       flag_dump_defs = 1;
+                       break;
+               case 'r':
+                       flag_reference = 1;
+                       ref_file = fopen(optarg, "r");
+                       if (!ref_file) {
+                               perror(optarg);
+                               return 1;
+                       }
+                       break;
+               case 'T':
+                       flag_dump_types = 1;
+                       dumpfile = fopen(optarg, "w");
+                       if (!dumpfile) {
+                               perror(optarg);
+                               return 1;
+                       }
+                       break;
+               case 'p':
+                       flag_preserve = 1;
+                       break;
+               case 'h':
+                       genksyms_usage();
+                       return 0;
+               default:
+                       genksyms_usage();
+                       return 1;
+               }
+       {
+               extern int yydebug;
+               extern int yy_flex_debug;
+
+               yydebug = (flag_debug > 1);
+               yy_flex_debug = (flag_debug > 2);
+
+               debugfile = stderr;
+               /* setlinebuf(debugfile); */
+       }
+
+       if (flag_reference) {
+               read_reference(ref_file);
+               fclose(ref_file);
+       }
+
+       yyparse();
+
+       if (flag_dump_types && visited_symbols) {
+               while (visited_symbols != (struct symbol *)-1L) {
+                       struct symbol *sym = visited_symbols;
+
+                       if (sym->is_override)
+                               fputs("override ", dumpfile);
+                       if (symbol_types[sym->type].n) {
+                               putc(symbol_types[sym->type].n, dumpfile);
+                               putc('#', dumpfile);
+                       }
+                       fputs(sym->name, dumpfile);
+                       putc(' ', dumpfile);
+                       if (sym->is_extern)
+                               fputs("extern ", dumpfile);
+                       print_list(dumpfile, sym->defn);
+                       putc('\n', dumpfile);
+
+                       visited_symbols = sym->visited;
+                       sym->visited = NULL;
+               }
+       }
+
+       if (flag_debug) {
+               fprintf(debugfile, "Hash table occupancy %d/%d = %g\n",
+                       nsyms, HASH_BUCKETS,
+                       (double)nsyms / (double)HASH_BUCKETS);
+       }
+
+       return errors != 0;
+}