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-rw-r--r--libebl/eblwstrtab.c344
1 files changed, 344 insertions, 0 deletions
diff --git a/libebl/eblwstrtab.c b/libebl/eblwstrtab.c
new file mode 100644
index 00000000..8320cb58
--- /dev/null
+++ b/libebl/eblwstrtab.c
@@ -0,0 +1,344 @@
+/* ELF string table handling.
+ Copyright (C) 2000, 2001, 2002 Red Hat, Inc.
+ Written by Ulrich Drepper <drepper@redhat.com>, 2000.
+
+ This program is Open Source software; you can redistribute it and/or
+ modify it under the terms of the Open Software License version 1.0 as
+ published by the Open Source Initiative.
+
+ You should have received a copy of the Open Software License along
+ with this program; if not, you may obtain a copy of the Open Software
+ License version 1.0 from http://www.opensource.org/licenses/osl.php or
+ by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
+ 3001 King Ranch Road, Ukiah, CA 95482. */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <inttypes.h>
+#include <libelf.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <wchar.h>
+#include <sys/param.h>
+
+#include "libebl.h"
+#include <system.h>
+
+#ifndef MIN
+# define MIN(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+
+struct Ebl_WStrent
+{
+ const wchar_t *string;
+ size_t len;
+ struct Ebl_WStrent *next;
+ struct Ebl_WStrent *left;
+ struct Ebl_WStrent *right;
+ size_t offset;
+ wchar_t reverse[0];
+};
+
+
+struct memoryblock
+{
+ struct memoryblock *next;
+ char memory[0];
+};
+
+
+struct Ebl_WStrtab
+{
+ struct Ebl_WStrent *root;
+ struct memoryblock *memory;
+ char *backp;
+ size_t left;
+ size_t total;
+ bool nullstr;
+
+ struct Ebl_WStrent null;
+};
+
+
+/* Cache for the pagesize. We correct this value a bit so that `malloc'
+ is not allocating more than a page. */
+static size_t ps;
+
+
+struct Ebl_WStrtab *
+ebl_wstrtabinit (bool nullstr)
+{
+ struct Ebl_WStrtab *ret;
+
+ if (ps == 0)
+ {
+ ps = sysconf (_SC_PAGESIZE) - 2 * sizeof (void *);
+ assert (sizeof (struct memoryblock) < ps);
+ }
+
+ ret = (struct Ebl_WStrtab *) calloc (1, sizeof (struct Ebl_WStrtab));
+ if (ret != NULL)
+ {
+ ret->nullstr = nullstr;
+ if (nullstr)
+ {
+ ret->null.len = 1;
+ ret->null.string = L"";
+ }
+ }
+ return ret;
+}
+
+
+static int
+morememory (struct Ebl_WStrtab *st, size_t len)
+{
+ struct memoryblock *newmem;
+
+ if (len < ps)
+ len = ps;
+ newmem = (struct memoryblock *) malloc (len);
+ if (newmem == NULL)
+ return 1;
+
+ newmem->next = st->memory;
+ st->memory = newmem;
+ st->backp = newmem->memory;
+ st->left = len - offsetof (struct memoryblock, memory);
+
+ return 0;
+}
+
+
+void
+ebl_wstrtabfree (struct Ebl_WStrtab *st)
+{
+ struct memoryblock *mb = st->memory;
+
+ while (mb != NULL)
+ {
+ void *old = mb;
+ mb = mb->next;
+ free (old);
+ }
+
+ free (st);
+}
+
+
+static struct Ebl_WStrent *
+newstring (struct Ebl_WStrtab *st, const wchar_t *str, size_t len)
+{
+ struct Ebl_WStrent *newstr;
+ size_t align;
+ int i;
+
+ /* Compute the amount of padding needed to make the structure aligned. */
+ align = ((__alignof__ (struct Ebl_WStrent)
+ - (((uintptr_t) st->backp)
+ & (__alignof__ (struct Ebl_WStrent) - 1)))
+ & (__alignof__ (struct Ebl_WStrent) - 1));
+
+ /* Make sure there is enough room in the memory block. */
+ if (st->left < align + sizeof (struct Ebl_WStrent) + len * sizeof (wchar_t))
+ {
+ if (morememory (st,
+ sizeof (struct Ebl_WStrent) + len * sizeof (wchar_t)))
+ return NULL;
+
+ align = 0;
+ }
+
+ /* Create the reserved string. */
+ newstr = (struct Ebl_WStrent *) (st->backp + align);
+ newstr->string = str;
+ newstr->len = len;
+ newstr->next = NULL;
+ newstr->left = NULL;
+ newstr->right = NULL;
+ newstr->offset = 0;
+ for (i = len - 2; i >= 0; --i)
+ newstr->reverse[i] = str[len - 2 - i];
+ newstr->reverse[len - 1] = L'\0';
+ st->backp += align + sizeof (struct Ebl_WStrent) + len * sizeof (wchar_t);
+ st->left -= align + sizeof (struct Ebl_WStrent) + len * sizeof (wchar_t);
+
+ return newstr;
+}
+
+
+/* XXX This function should definitely be rewritten to use a balancing
+ tree algorith (AVL, red-black trees). For now a simple, correct
+ implementation is enough. */
+static struct Ebl_WStrent **
+searchstring (struct Ebl_WStrent **sep, struct Ebl_WStrent *newstr)
+{
+ int cmpres;
+
+ /* More strings? */
+ if (*sep == NULL)
+ {
+ *sep = newstr;
+ return sep;
+ }
+
+ /* Compare the strings. */
+ cmpres = wmemcmp ((*sep)->reverse, newstr->reverse,
+ MIN ((*sep)->len, newstr->len) - 1);
+ if (cmpres == 0)
+ /* We found a matching string. */
+ return sep;
+ else if (cmpres > 0)
+ return searchstring (&(*sep)->left, newstr);
+ else
+ return searchstring (&(*sep)->right, newstr);
+}
+
+
+/* Add new string. The actual string is assumed to be permanent. */
+struct Ebl_WStrent *
+ebl_wstrtabadd (struct Ebl_WStrtab *st, const wchar_t *str, size_t len)
+{
+ struct Ebl_WStrent *newstr;
+ struct Ebl_WStrent **sep;
+
+ /* Compute the string length if the caller doesn't know it. */
+ if (len == 0)
+ len = wcslen (str) + 1;
+
+ /* Make sure all "" strings get offset 0 but only if the table was
+ created with a special null entry in mind. */
+ if (len == 1 && st->null.string != NULL)
+ return &st->null;
+
+ /* Allocate memory for the new string and its associated information. */
+ newstr = newstring (st, str, len);
+ if (newstr == NULL)
+ return NULL;
+
+ /* Search in the array for the place to insert the string. If there
+ is no string with matching prefix and no string with matching
+ leading substring, create a new entry. */
+ sep = searchstring (&st->root, newstr);
+ if (*sep != newstr)
+ {
+ /* This is not the same entry. This means we have a prefix match. */
+ if ((*sep)->len > newstr->len)
+ {
+ struct Ebl_WStrent *subs;
+
+ /* Check whether we already know this string. */
+ for (subs = (*sep)->next; subs != NULL; subs = subs->next)
+ if (subs->len == newstr->len)
+ {
+ /* We have an exact match with a substring. Free the memory
+ we allocated. */
+ st->left += st->backp - (char *) newstr;
+ st->backp = (char *) newstr;
+
+ return subs;
+ }
+
+ /* We have a new substring. This means we don't need the reverse
+ string of this entry anymore. */
+ st->backp -= newstr->len;
+ st->left += newstr->len;
+
+ newstr->next = (*sep)->next;
+ (*sep)->next = newstr;
+ }
+ else if ((*sep)->len != newstr->len)
+ {
+ /* When we get here it means that the string we are about to
+ add has a common prefix with a string we already have but
+ it is longer. In this case we have to put it first. */
+ st->total += newstr->len - (*sep)->len;
+ newstr->next = *sep;
+ newstr->left = (*sep)->left;
+ newstr->right = (*sep)->right;
+ *sep = newstr;
+ }
+ else
+ {
+ /* We have an exact match. Free the memory we allocated. */
+ st->left += st->backp - (char *) newstr;
+ st->backp = (char *) newstr;
+
+ newstr = *sep;
+ }
+ }
+ else
+ st->total += newstr->len;
+
+ return newstr;
+}
+
+
+static void
+copystrings (struct Ebl_WStrent *nodep, wchar_t **freep, size_t *offsetp)
+{
+ struct Ebl_WStrent *subs;
+
+ if (nodep->left != NULL)
+ copystrings (nodep->left, freep, offsetp);
+
+ /* Process the current node. */
+ nodep->offset = *offsetp;
+ *freep = wmempcpy (*freep, nodep->string, nodep->len);
+ *offsetp += nodep->len * sizeof (wchar_t);
+
+ for (subs = nodep->next; subs != NULL; subs = subs->next)
+ {
+ assert (subs->len < nodep->len);
+ subs->offset = nodep->offset + nodep->len - subs->len;
+ assert (subs->offset != 0 || subs->string[0] == '\0');
+ }
+
+ if (nodep->right != NULL)
+ copystrings (nodep->right, freep, offsetp);
+}
+
+
+void
+ebl_wstrtabfinalize (struct Ebl_WStrtab *st, Elf_Data *data)
+{
+ size_t copylen;
+ wchar_t *endp;
+ size_t nulllen = st->nullstr ? 1 : 0;
+
+ /* Fill in the information. */
+ data->d_buf = malloc ((st->total + nulllen) * sizeof (wchar_t));
+ if (data->d_buf == NULL)
+ abort ();
+
+ /* The first byte must always be zero if we created the table with a
+ null string. */
+ if (st->nullstr)
+ *((wchar_t *) data->d_buf) = L'\0';
+
+ data->d_type = ELF_T_BYTE;
+ data->d_size = st->total + nulllen;
+ data->d_off = 0;
+ data->d_align = 1;
+ data->d_version = EV_CURRENT;
+
+ /* Now run through the tree and add all the string while also updating
+ the offset members of the elfstrent records. */
+ endp = (wchar_t *) data->d_buf + nulllen;
+ copylen = sizeof (wchar_t) * nulllen;
+ copystrings (st->root, &endp, &copylen);
+ assert (copylen == (st->total + nulllen) * sizeof (wchar_t));
+}
+
+
+size_t
+ebl_wstrtaboffset (struct Ebl_WStrent *se)
+{
+ return se->offset;
+}
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