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-rw-r--r--mdk-stage1/slang/slstring.c546
1 files changed, 0 insertions, 546 deletions
diff --git a/mdk-stage1/slang/slstring.c b/mdk-stage1/slang/slstring.c
deleted file mode 100644
index 529c41827..000000000
--- a/mdk-stage1/slang/slstring.c
+++ /dev/null
@@ -1,546 +0,0 @@
-/* Copyright (c) 1998, 1999, 2001 John E. Davis
- * This file is part of the S-Lang library.
- *
- * You may distribute under the terms of either the GNU General Public
- * License or the Perl Artistic License.
- */
-#include "slinclud.h"
-
-#include "slang.h"
-#include "_slang.h"
-
-typedef struct _SLstring_Type
-{
- struct _SLstring_Type *next;
- unsigned int ref_count;
- char bytes [1];
-}
-SLstring_Type;
-
-static SLstring_Type *String_Hash_Table [SLSTRING_HASH_TABLE_SIZE];
-static char Single_Char_Strings [256 * 2];
-
-#if _SLANG_OPTIMIZE_FOR_SPEED
-#define MAX_FREE_STORE_LEN 32
-static SLstring_Type *SLS_Free_Store [MAX_FREE_STORE_LEN];
-
-# define NUM_CACHED_STRINGS 601
-typedef struct
-{
- unsigned long hash;
- SLstring_Type *sls;
- unsigned int len;
-}
-Cached_String_Type;
-static Cached_String_Type Cached_Strings [NUM_CACHED_STRINGS];
-
-#define GET_CACHED_STRING(s) \
- (Cached_Strings + (unsigned int)(((unsigned long) (s)) % NUM_CACHED_STRINGS))
-
-_INLINE_
-static void cache_string (SLstring_Type *sls, unsigned int len, unsigned long hash)
-{
- Cached_String_Type *cs;
-
- cs = GET_CACHED_STRING(sls->bytes);
- cs->sls = sls;
- cs->hash = hash;
- cs->len = len;
-}
-
-_INLINE_
-static void uncache_string (char *s)
-{
- Cached_String_Type *cs;
-
- cs = GET_CACHED_STRING(s);
- if ((cs->sls != NULL)
- && (cs->sls->bytes == s))
- cs->sls = NULL;
-}
-#endif
-
-
-
-_INLINE_
-unsigned long _SLstring_hash (unsigned char *s, unsigned char *smax)
-{
- register unsigned long h = 0;
- register unsigned long sum = 0;
- unsigned char *smax4;
-
- smax4 = smax - 4;
-
- while (s < smax4)
- {
- sum += s[0];
- h = sum + (h << 1);
- sum += s[1];
- h = sum + (h << 1);
- sum += s[2];
- h = sum + (h << 1);
- sum += s[3];
- h = sum + (h << 1);
-
- s += 4;
- }
-
- while (s < smax)
- {
- sum += *s++;
- h ^= sum + (h << 3); /* slightly different */
- }
-
- return h;
-}
-
-unsigned long _SLcompute_string_hash (char *s)
-{
-#if _SLANG_OPTIMIZE_FOR_SPEED
- Cached_String_Type *cs;
- SLstring_Type *sls;
-
- cs = GET_CACHED_STRING(s);
- if (((sls = cs->sls) != NULL)
- && (sls->bytes == s))
- return cs->hash;
-#endif
- return _SLstring_hash ((unsigned char *) s, (unsigned char *) s + strlen (s));
-}
-
-_INLINE_
-/* This routine works with any (long) string */
-static SLstring_Type *find_string (char *s, unsigned int len, unsigned long hash)
-{
- SLstring_Type *sls;
- char ch;
-
- sls = String_Hash_Table [(unsigned int)(hash % SLSTRING_HASH_TABLE_SIZE)];
-
- if (sls == NULL)
- return NULL;
-
- ch = s[0];
- do
- {
- char *bytes = sls->bytes;
-
- /* Note that we need to actually make sure that bytes[len] == 0.
- * In this case, it is not enough to just compare pointers. In fact,
- * this is called from create_nstring, etc... It is unlikely that the
- * pointer is a slstring
- */
- if ((/* (s == bytes) || */ ((ch == bytes[0])
- && (0 == strncmp (s, bytes, len))))
- && (bytes [len] == 0))
- break;
-
- sls = sls->next;
- }
- while (sls != NULL);
-
- return sls;
-}
-
-_INLINE_
-static SLstring_Type *find_slstring (char *s, unsigned long hash)
-{
- SLstring_Type *sls;
-
- sls = String_Hash_Table [(unsigned int)(hash % SLSTRING_HASH_TABLE_SIZE)];
- while (sls != NULL)
- {
- if (s == sls->bytes)
- return sls;
-
- sls = sls->next;
- }
- return sls;
-}
-
-_INLINE_
-static SLstring_Type *allocate_sls (unsigned int len)
-{
- SLstring_Type *sls;
-
-#if _SLANG_OPTIMIZE_FOR_SPEED
- if ((len < MAX_FREE_STORE_LEN)
- && (NULL != (sls = SLS_Free_Store [len])))
- {
- SLS_Free_Store[len] = NULL;
- return sls;
- }
-#endif
- /* FIXME: use structure padding */
- return (SLstring_Type *) SLmalloc (len + sizeof (SLstring_Type));
-}
-
-_INLINE_
-static void free_sls (SLstring_Type *sls, unsigned int len)
-{
-#if _SLANG_OPTIMIZE_FOR_SPEED
- if ((len < MAX_FREE_STORE_LEN)
- && (SLS_Free_Store[len] == NULL))
- {
- SLS_Free_Store [len] = sls;
- return;
- }
-#else
- (void) len;
-#endif
- SLfree ((char *)sls);
-}
-
-_INLINE_
-static char *create_long_string (char *s, unsigned int len, unsigned long hash)
-{
- SLstring_Type *sls;
-
- sls = find_string (s, len, hash);
-
- if (sls != NULL)
- {
- sls->ref_count++;
- s = sls->bytes;
-
-#if _SLANG_OPTIMIZE_FOR_SPEED
- cache_string (sls, len, hash);
-#endif
- return s;
- }
-
- sls = allocate_sls (len);
- if (sls == NULL)
- return NULL;
-
- strncpy (sls->bytes, s, len);
- sls->bytes[len] = 0;
- sls->ref_count = 1;
-
-#if _SLANG_OPTIMIZE_FOR_SPEED
- cache_string (sls, len, hash);
-#endif
-
- hash = hash % SLSTRING_HASH_TABLE_SIZE;
- sls->next = String_Hash_Table [(unsigned int)hash];
- String_Hash_Table [(unsigned int)hash] = sls;
-
- return sls->bytes;
-}
-
-_INLINE_
-static char *create_short_string (char *s, unsigned int len)
-{
- char ch;
-
- /* Note: if len is 0, then it does not matter what *s is. This is
- * important for SLang_create_nslstring.
- */
- if (len) ch = *s; else ch = 0;
-
- len = 2 * (unsigned int) ((unsigned char) ch);
- Single_Char_Strings [len] = ch;
- Single_Char_Strings [len + 1] = 0;
- return Single_Char_Strings + len;
-}
-
-/* s cannot be NULL */
-_INLINE_
-static char *create_nstring (char *s, unsigned int len, unsigned long *hash_ptr)
-{
- unsigned long hash;
-
- if (len < 2)
- return create_short_string (s, len);
-
- hash = _SLstring_hash ((unsigned char *) s, (unsigned char *) (s + len));
- *hash_ptr = hash;
-
- return create_long_string (s, len, hash);
-}
-
-char *SLang_create_nslstring (char *s, unsigned int len)
-{
- unsigned long hash;
- return create_nstring (s, len, &hash);
-}
-
-char *_SLstring_make_hashed_string (char *s, unsigned int len, unsigned long *hashptr)
-{
- unsigned long hash;
-
- if (s == NULL) return NULL;
-
- hash = _SLstring_hash ((unsigned char *) s, (unsigned char *) s + len);
- *hashptr = hash;
-
- if (len < 2)
- return create_short_string (s, len);
-
- return create_long_string (s, len, hash);
-}
-
-char *_SLstring_dup_hashed_string (char *s, unsigned long hash)
-{
- unsigned int len;
-#if _SLANG_OPTIMIZE_FOR_SPEED
- Cached_String_Type *cs;
- SLstring_Type *sls;
-
- if (s == NULL) return NULL;
- if (s[0] == 0)
- return create_short_string (s, 0);
- if (s[1] == 0)
- return create_short_string (s, 1);
-
- cs = GET_CACHED_STRING(s);
- if (((sls = cs->sls) != NULL)
- && (sls->bytes == s))
- {
- sls->ref_count += 1;
- return s;
- }
-#else
- if (s == NULL) return NULL;
-#endif
-
- len = strlen (s);
-#if !_SLANG_OPTIMIZE_FOR_SPEED
- if (len < 2) return create_short_string (s, len);
-#endif
-
- return create_long_string (s, len, hash);
-}
-
-char *_SLstring_dup_slstring (char *s)
-{
- SLstring_Type *sls;
- unsigned int len;
- unsigned long hash;
-#if _SLANG_OPTIMIZE_FOR_SPEED
- Cached_String_Type *cs;
-
- cs = GET_CACHED_STRING(s);
- if (((sls = cs->sls) != NULL)
- && (sls->bytes == s))
- {
- sls->ref_count += 1;
- return s;
- }
-#endif
-
- if ((s == NULL) || ((len = strlen (s)) < 2))
- return s;
-
- hash = _SLstring_hash ((unsigned char *)s, (unsigned char *)(s + len));
-
- sls = find_slstring (s, hash);
- if (sls == NULL)
- {
- SLang_Error = SL_INTERNAL_ERROR;
- return NULL;
- }
-
- sls->ref_count++;
-#if _SLANG_OPTIMIZE_FOR_SPEED
- cache_string (sls, len, hash);
-#endif
- return s;
-}
-
-static void free_sls_string (SLstring_Type *sls, char *s, unsigned int len,
- unsigned long hash)
-{
- SLstring_Type *sls1, *prev;
-
-#if _SLANG_OPTIMIZE_FOR_SPEED
- uncache_string (s);
-#endif
-
- hash = hash % SLSTRING_HASH_TABLE_SIZE;
-
- sls1 = String_Hash_Table [(unsigned int) hash];
-
- prev = NULL;
-
- /* This should not fail. */
- while (sls1 != sls)
- {
- prev = sls1;
- sls1 = sls1->next;
- }
-
- if (prev != NULL)
- prev->next = sls->next;
- else
- String_Hash_Table [(unsigned int) hash] = sls->next;
-
- free_sls (sls, len);
-}
-
-_INLINE_
-static void free_long_string (char *s, unsigned int len, unsigned long hash)
-{
- SLstring_Type *sls;
-
- if (NULL == (sls = find_slstring (s, hash)))
- {
- SLang_doerror ("Application internal error: invalid attempt to free string");
- return;
- }
-
- sls->ref_count--;
- if (sls->ref_count != 0)
- {
-#if _SLANG_OPTIMIZE_FOR_SPEED
- /* cache_string (sls, len, hash); */
-#endif
- return;
- }
-
-
- free_sls_string (sls, s, len, hash);
-}
-
-/* This routine may be passed NULL-- it is not an error. */
-void SLang_free_slstring (char *s)
-{
- unsigned long hash;
- unsigned int len;
-#if _SLANG_OPTIMIZE_FOR_SPEED
- Cached_String_Type *cs;
- SLstring_Type *sls;
-
- cs = GET_CACHED_STRING(s);
- if (((sls = cs->sls) != NULL)
- && (sls->bytes == s))
- {
- if (sls->ref_count <= 1)
- free_sls_string (sls, s, cs->len, cs->hash);
- else
- sls->ref_count -= 1;
- return;
- }
-#endif
-
- if (s == NULL) return;
-
- if ((len = strlen (s)) < 2)
- return;
-
- hash = _SLstring_hash ((unsigned char *)s, (unsigned char *) s + len);
- free_long_string (s, len, hash);
-}
-
-char *SLang_create_slstring (char *s)
-{
- unsigned long hash;
-#if _SLANG_OPTIMIZE_FOR_SPEED
- Cached_String_Type *cs;
- SLstring_Type *sls;
-
- cs = GET_CACHED_STRING(s);
- if (((sls = cs->sls) != NULL)
- && (sls->bytes == s))
- {
- sls->ref_count += 1;
- return s;
- }
-#endif
-
- if (s == NULL) return NULL;
- return create_nstring (s, strlen (s), &hash);
-}
-
-void _SLfree_hashed_string (char *s, unsigned int len, unsigned long hash)
-{
- if ((s == NULL) || (len < 2)) return;
- free_long_string (s, len, hash);
-}
-
-
-char *_SLallocate_slstring (unsigned int len)
-{
- SLstring_Type *sls = allocate_sls (len);
- if (sls == NULL)
- return NULL;
-
- return sls->bytes;
-}
-
-void _SLunallocate_slstring (char *s, unsigned int len)
-{
- SLstring_Type *sls;
-
- if (s == NULL)
- return;
-
- sls = (SLstring_Type *) (s - offsetof(SLstring_Type,bytes[0]));
- free_sls (sls, len);
-}
-
-char *_SLcreate_via_alloced_slstring (char *s, unsigned int len)
-{
- unsigned long hash;
- SLstring_Type *sls;
-
- if (s == NULL)
- return NULL;
-
- if (len < 2)
- {
- char *s1 = create_short_string (s, len);
- _SLunallocate_slstring (s, len);
- return s1;
- }
-
- /* s is not going to be in the cache because when it was malloced, its
- * value was unknown. This simplifies the coding.
- */
- hash = _SLstring_hash ((unsigned char *)s, (unsigned char *)s + len);
- sls = find_string (s, len, hash);
- if (sls != NULL)
- {
- sls->ref_count++;
- _SLunallocate_slstring (s, len);
- s = sls->bytes;
-
-#if _SLANG_OPTIMIZE_FOR_SPEED
- cache_string (sls, len, hash);
-#endif
- return s;
- }
-
- sls = (SLstring_Type *) (s - offsetof(SLstring_Type,bytes[0]));
- sls->ref_count = 1;
-
-#if _SLANG_OPTIMIZE_FOR_SPEED
- cache_string (sls, len, hash);
-#endif
-
- hash = hash % SLSTRING_HASH_TABLE_SIZE;
- sls->next = String_Hash_Table [(unsigned int)hash];
- String_Hash_Table [(unsigned int)hash] = sls;
-
- return s;
-}
-
-/* Note, a and b may be ordinary strings. The result is an slstring */
-char *SLang_concat_slstrings (char *a, char *b)
-{
- unsigned int lena, len;
- char *c;
-
- lena = strlen (a);
- len = lena + strlen (b);
-
- c = _SLallocate_slstring (len);
- if (c == NULL)
- return NULL;
-
- strcpy (c, a);
- strcpy (c + lena, b);
-
- return _SLcreate_via_alloced_slstring (c, len);
-}
-
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