mono/metadata/string-icalls.c

   1 /*
   2  * string-icalls.c: String internal calls for the corlib
   3  *
   4  * Author:
   5  *   Patrik Torstensson (patrik.torstensson@labs2.com)
   6  *   Duncan Mak  (duncan@ximian.com)
   7  *
   8  * Copyright 2001-2003 Ximian, Inc (http://www.ximian.com)
   9  * Copyright 2004-2009 Novell, Inc (http://www.novell.com)
  10  */
  11 #include <config.h>
  12 #include <stdlib.h>
  13 #include <stdio.h>
  14 #include <signal.h>
  15 #include <string.h>
  16 #include "mono/utils/mono-membar.h"
  17 #include <mono/metadata/string-icalls.h>
  18 #include <mono/metadata/class-internals.h>
  19 #include <mono/metadata/appdomain.h>
  20 #include <mono/metadata/tabledefs.h>
  21 #include <mono/metadata/loader.h>
  22 #include <mono/metadata/object.h>
  23 #include <mono/metadata/exception.h>
  24 #include <mono/metadata/debug-helpers.h>
  25 #include <mono/metadata/profiler.h>
  26 #include <mono/metadata/profiler-private.h>
  27 #include <mono/metadata/gc-internal.h>
  28
  29 /* Internal helper methods */
  30
  31 static gboolean
  32 string_icall_is_in_array (MonoArray *chars, gint32 arraylength, gunichar2 chr);
  33
  34 /* This function is redirected to String.CreateString ()
  35    by mono_marshal_get_native_wrapper () */
  36 void
  37 ves_icall_System_String_ctor_RedirectToCreateString (void)
  38 {
  39         g_assert_not_reached ();
  40 }
  41
  42 /* System.StringSplitOptions */
  43 typedef enum {
  44         STRINGSPLITOPTIONS_NONE = 0,
  45         STRINGSPLITOPTIONS_REMOVE_EMPTY_ENTRIES = 1
  46 } StringSplitOptions;
  47
  48 MonoArray *
  49 ves_icall_System_String_InternalSplit (MonoString *me, MonoArray *separator, gint32 count, gint32 options)
  50 {
  51         static MonoClass *String_array;
  52         MonoString * tmpstr;
  53         MonoArray * retarr;
  54         gunichar2 *src;
  55         gint32 arrsize, srcsize, splitsize;
  56         gint32 i, lastpos, arrpos;
  57         gint32 tmpstrsize;
  58         gint32 remempty;
  59         gint32 flag;
  60         gunichar2 *tmpstrptr;
  61
  62         remempty = options & STRINGSPLITOPTIONS_REMOVE_EMPTY_ENTRIES;
  63         src = mono_string_chars (me);
  64         srcsize = mono_string_length (me);
  65         arrsize = mono_array_length (separator);
  66
  67         if (!String_array) {
  68                 MonoClass *klass = mono_array_class_get (mono_get_string_class (), 1);
  69                 mono_memory_barrier ();
  70                 String_array = klass;
  71         }
  72
  73         splitsize = 1;
  74         /* Count the number of elements we will return. Note that this operation
  75          * guarantees that we will return exactly splitsize elements, and we will
  76          * have enough data to fill each. This allows us to skip some checks later on.
  77          */
  78         if (remempty == 0) {
  79                 for (i = 0; i != srcsize && splitsize < count; i++) {
  80                         if (string_icall_is_in_array (separator, arrsize, src [i]))
  81                                 splitsize++;
  82                 }
  83         } else if (count > 1) {
  84                 /* Require pattern "Nondelim + Delim + Nondelim" to increment counter.
  85                  * Lastpos != 0 means first nondelim found.
  86                  * Flag = 0 means last char was delim.
  87                  * Efficient, though perhaps confusing.
  88                  */
  89                 lastpos = 0;
  90                 flag = 0;
  91                 for (i = 0; i != srcsize && splitsize < count; i++) {
  92                         if (string_icall_is_in_array (separator, arrsize, src [i])) {
  93                                 flag = 0;
  94                         } else if (flag == 0) {
  95                                 if (lastpos == 1)
  96                                         splitsize++;
  97                                 flag = 1;
  98                                 lastpos = 1;
  99                         }
 100                 }
 101
 102                 /* Nothing but separators */
 103                 if (lastpos == 0) {
 104                         retarr = mono_array_new_specific (mono_class_vtable (mono_domain_get (), String_array), 0);
 105                         return retarr;
 106                 }
 107         }
 108
 109         /* if no split chars found return the string */
 110         if (splitsize == 1) {
 111                 if (remempty == 0 || count == 1) {
 112                         /* Copy the whole string */
 113                         retarr = mono_array_new_specific (mono_class_vtable (mono_domain_get (), String_array), 1);
 114                         mono_array_setref (retarr, 0, me);
 115                 } else {
 116                         /* otherwise we have to filter out leading & trailing delims */
 117
 118                         /* find first non-delim char */
 119                         for (; srcsize != 0; srcsize--, src++) {
 120                                 if (!string_icall_is_in_array (separator, arrsize, src [0]))
 121                                         break;
 122                         }
 123                         /* find last non-delim char */
 124                         for (; srcsize != 0; srcsize--) {
 125                                 if (!string_icall_is_in_array (separator, arrsize, src [srcsize - 1]))
 126                                         break;
 127                         }
 128                         tmpstr = mono_string_new_size (mono_domain_get (), srcsize);
 129                         tmpstrptr = mono_string_chars (tmpstr);
 130
 131                         memcpy (tmpstrptr, src, srcsize * sizeof (gunichar2));
 132                         retarr = mono_array_new_specific (mono_class_vtable (mono_domain_get (), String_array), 1);
 133                         mono_array_setref (retarr, 0, tmpstr);
 134                 }
 135                 return retarr;
 136         }
 137
 138         lastpos = 0;
 139         arrpos = 0;
 140
 141         retarr = mono_array_new_specific (mono_class_vtable (mono_domain_get (), String_array), splitsize);
 142
 143         for (i = 0; i != srcsize && arrpos != splitsize; i++) {
 144                 if (string_icall_is_in_array (separator, arrsize, src [i])) {
 145
 146                         if (lastpos != i || remempty == 0) {
 147                                 tmpstrsize = i - lastpos;
 148                                 tmpstr = mono_string_new_size (mono_domain_get (), tmpstrsize);
 149                                 tmpstrptr = mono_string_chars (tmpstr);
 150
 151                                 memcpy (tmpstrptr, src + lastpos, tmpstrsize * sizeof (gunichar2));
 152                                 mono_array_setref (retarr, arrpos, tmpstr);
 153                                 arrpos++;
 154
 155                                 if (arrpos == splitsize - 1) {
 156                                         /* Shortcut the last array element */
 157
 158                                         lastpos = i + 1;
 159                                         if (remempty != 0) {
 160                                                 /* Search for non-delim starting char (guaranteed to find one) Note that loop
 161                                                  * condition is only there for safety. It will never actually terminate the loop. */
 162                                                 for (; lastpos != srcsize ; lastpos++) {
 163                                                         if (!string_icall_is_in_array (separator, arrsize, src [lastpos]))
 164                                                                 break;
 165                                                 }
 166                                                 if (count > splitsize) {
 167                                                         /* Since we have fewer results than our limit, we must remove
 168                                                          * trailing delimiters as well.
 169                                                          */
 170                                                         for (; srcsize != lastpos + 1 ; srcsize--) {
 171                                                                 if (!string_icall_is_in_array (separator, arrsize, src [srcsize - 1]))
 172                                                                         break;
 173                                                         }
 174                                                 }
 175                                         }
 176
 177                                         tmpstrsize = srcsize - lastpos;
 178                                         tmpstr = mono_string_new_size (mono_domain_get (), tmpstrsize);
 179                                         tmpstrptr = mono_string_chars (tmpstr);
 180
 181                                         memcpy (tmpstrptr, src + lastpos, tmpstrsize * sizeof (gunichar2));
 182                                         mono_array_setref (retarr, arrpos, tmpstr);
 183
 184                                         /* Loop will ALWAYS end here. Test criteria in the FOR loop is technically unnecessary. */
 185                                         break;
 186                                 }
 187                         }
 188                         lastpos = i + 1;
 189                 }
 190         }
 191
 192         return retarr;
 193 }
 194
 195 static gboolean
 196 string_icall_is_in_array (MonoArray *chars, gint32 arraylength, gunichar2 chr)
 197 {
 198         gunichar2 cmpchar;
 199         gint32 arrpos;
 200
 201         for (arrpos = 0; arrpos != arraylength; arrpos++) {
 202                 cmpchar = mono_array_get(chars, gunichar2, arrpos);
 203                 if (cmpchar == chr)
 204                         return TRUE;
 205         }
 206
 207         return FALSE;
 208 }
 209
 210 MonoString *
 211 ves_icall_System_String_InternalAllocateStr (gint32 length)
 212 {
 213         return mono_string_new_size(mono_domain_get (), length);
 214 }
 215
 216 MonoString  *
 217 ves_icall_System_String_InternalIntern (MonoString *str)
 218 {
 219         MONO_ARCH_SAVE_REGS;
 220
 221         return mono_string_intern(str);
 222 }
 223
 224 MonoString *
 225 ves_icall_System_String_InternalIsInterned (MonoString *str)
 226 {
 227         MONO_ARCH_SAVE_REGS;
 228
 229         return mono_string_is_interned(str);
 230 }
 231
 232 int
 233 ves_icall_System_String_GetLOSLimit (void)
 234 {
 235 #ifdef HAVE_SGEN_GC
 236         int limit = mono_gc_get_los_limit ();
 237
 238         return (limit - 2 - sizeof (MonoString)) / 2;
 239 #else
 240         return G_MAXINT;
 241 #endif
 242 }