src/external/pcre2-10.32/src/sljit/sljitUtils.c

   1 /*
   2  *    Stack-less Just-In-Time compiler
   3  *
   4  *    Copyright Zoltan Herczeg (hzmester@freemail.hu). All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without modification, are
   7  * permitted provided that the following conditions are met:
   8  *
   9  *   1. Redistributions of source code must retain the above copyright notice, this list of
  10  *      conditions and the following disclaimer.
  11  *
  12  *   2. Redistributions in binary form must reproduce the above copyright notice, this list
  13  *      of conditions and the following disclaimer in the documentation and/or other materials
  14  *      provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) AND CONTRIBUTORS ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  19  * SHALL THE COPYRIGHT HOLDER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  21  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  22  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  24  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 /* ------------------------------------------------------------------------ */
  28 /*  Locks                                                                   */
  29 /* ------------------------------------------------------------------------ */
  30
  31 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) || (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
  32
  33 #if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED)
  34
  35 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
  36
  37 static SLJIT_INLINE void allocator_grab_lock(void)
  38 {
  39         /* Always successful. */
  40 }
  41
  42 static SLJIT_INLINE void allocator_release_lock(void)
  43 {
  44         /* Always successful. */
  45 }
  46
  47 #endif /* SLJIT_EXECUTABLE_ALLOCATOR */
  48
  49 #if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
  50
  51 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_grab_lock(void)
  52 {
  53         /* Always successful. */
  54 }
  55
  56 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_release_lock(void)
  57 {
  58         /* Always successful. */
  59 }
  60
  61 #endif /* SLJIT_UTIL_GLOBAL_LOCK */
  62
  63 #elif defined(_WIN32) /* SLJIT_SINGLE_THREADED */
  64
  65 #include "windows.h"
  66
  67 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
  68
  69 static HANDLE allocator_mutex = 0;
  70
  71 static SLJIT_INLINE void allocator_grab_lock(void)
  72 {
  73         /* No idea what to do if an error occures. Static mutexes should never fail... */
  74         if (!allocator_mutex)
  75                 allocator_mutex = CreateMutex(NULL, TRUE, NULL);
  76         else
  77                 WaitForSingleObject(allocator_mutex, INFINITE);
  78 }
  79
  80 static SLJIT_INLINE void allocator_release_lock(void)
  81 {
  82         ReleaseMutex(allocator_mutex);
  83 }
  84
  85 #endif /* SLJIT_EXECUTABLE_ALLOCATOR */
  86
  87 #if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
  88
  89 static HANDLE global_mutex = 0;
  90
  91 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_grab_lock(void)
  92 {
  93         /* No idea what to do if an error occures. Static mutexes should never fail... */
  94         if (!global_mutex)
  95                 global_mutex = CreateMutex(NULL, TRUE, NULL);
  96         else
  97                 WaitForSingleObject(global_mutex, INFINITE);
  98 }
  99
 100 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_release_lock(void)
 101 {
 102         ReleaseMutex(global_mutex);
 103 }
 104
 105 #endif /* SLJIT_UTIL_GLOBAL_LOCK */
 106
 107 #else /* _WIN32 */
 108
 109 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
 110
 111 #include <pthread.h>
 112
 113 static pthread_mutex_t allocator_mutex = PTHREAD_MUTEX_INITIALIZER;
 114
 115 static SLJIT_INLINE void allocator_grab_lock(void)
 116 {
 117         pthread_mutex_lock(&allocator_mutex);
 118 }
 119
 120 static SLJIT_INLINE void allocator_release_lock(void)
 121 {
 122         pthread_mutex_unlock(&allocator_mutex);
 123 }
 124
 125 #endif /* SLJIT_EXECUTABLE_ALLOCATOR */
 126
 127 #if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
 128
 129 #include <pthread.h>
 130
 131 static pthread_mutex_t global_mutex = PTHREAD_MUTEX_INITIALIZER;
 132
 133 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_grab_lock(void)
 134 {
 135         pthread_mutex_lock(&global_mutex);
 136 }
 137
 138 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_release_lock(void)
 139 {
 140         pthread_mutex_unlock(&global_mutex);
 141 }
 142
 143 #endif /* SLJIT_UTIL_GLOBAL_LOCK */
 144
 145 #endif /* _WIN32 */
 146
 147 /* ------------------------------------------------------------------------ */
 148 /*  Stack                                                                   */
 149 /* ------------------------------------------------------------------------ */
 150
 151 #if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) || (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
 152
 153 #ifdef _WIN32
 154 #include "windows.h"
 155 #else
 156 /* Provides mmap function. */
 157 #include <sys/mman.h>
 158 /* For detecting the page size. */
 159 #include <unistd.h>
 160
 161 #ifndef MAP_ANON
 162
 163 #include <fcntl.h>
 164
 165 /* Some old systems does not have MAP_ANON. */
 166 static sljit_s32 dev_zero = -1;
 167
 168 #if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED)
 169
 170 static SLJIT_INLINE sljit_s32 open_dev_zero(void)
 171 {
 172         dev_zero = open("/dev/zero", O_RDWR);
 173         return dev_zero < 0;
 174 }
 175
 176 #else /* SLJIT_SINGLE_THREADED */
 177
 178 #include <pthread.h>
 179
 180 static pthread_mutex_t dev_zero_mutex = PTHREAD_MUTEX_INITIALIZER;
 181
 182 static SLJIT_INLINE sljit_s32 open_dev_zero(void)
 183 {
 184         pthread_mutex_lock(&dev_zero_mutex);
 185         /* The dev_zero might be initialized by another thread during the waiting. */
 186         if (dev_zero < 0) {
 187                 dev_zero = open("/dev/zero", O_RDWR);
 188         }
 189         pthread_mutex_unlock(&dev_zero_mutex);
 190         return dev_zero < 0;
 191 }
 192
 193 #endif /* SLJIT_SINGLE_THREADED */
 194
 195 #endif
 196
 197 #endif
 198
 199 #endif /* SLJIT_UTIL_STACK || SLJIT_EXECUTABLE_ALLOCATOR */
 200
 201 #if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK)
 202
 203 /* Planning to make it even more clever in the future. */
 204 static sljit_sw sljit_page_align = 0;
 205
 206 SLJIT_API_FUNC_ATTRIBUTE struct sljit_stack* SLJIT_FUNC sljit_allocate_stack(sljit_uw start_size, sljit_uw max_size, void *allocator_data)
 207 {
 208         struct sljit_stack *stack;
 209         void *ptr;
 210 #ifdef _WIN32
 211         SYSTEM_INFO si;
 212 #endif
 213
 214         SLJIT_UNUSED_ARG(allocator_data);
 215         if (start_size > max_size || start_size < 1)
 216                 return NULL;
 217
 218 #ifdef _WIN32
 219         if (!sljit_page_align) {
 220                 GetSystemInfo(&si);
 221                 sljit_page_align = si.dwPageSize - 1;
 222         }
 223 #else
 224         if (!sljit_page_align) {
 225                 sljit_page_align = sysconf(_SC_PAGESIZE);
 226                 /* Should never happen. */
 227                 if (sljit_page_align < 0)
 228                         sljit_page_align = 4096;
 229                 sljit_page_align--;
 230         }
 231 #endif
 232
 233         stack = (struct sljit_stack*)SLJIT_MALLOC(sizeof(struct sljit_stack), allocator_data);
 234         if (!stack)
 235                 return NULL;
 236
 237         /* Align max_size. */
 238         max_size = (max_size + sljit_page_align) & ~sljit_page_align;
 239
 240 #ifdef _WIN32
 241         ptr = VirtualAlloc(NULL, max_size, MEM_RESERVE, PAGE_READWRITE);
 242         if (!ptr) {
 243                 SLJIT_FREE(stack, allocator_data);
 244                 return NULL;
 245         }
 246
 247         stack->min_start = (sljit_u8 *)ptr;
 248         stack->end = stack->min_start + max_size;
 249         stack->start = stack->end;
 250
 251         if (sljit_stack_resize(stack, stack->end - start_size) == NULL) {
 252                 sljit_free_stack(stack, allocator_data);
 253                 return NULL;
 254         }
 255 #else
 256 #ifdef MAP_ANON
 257         ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
 258 #else
 259         if (dev_zero < 0) {
 260                 if (open_dev_zero()) {
 261                         SLJIT_FREE(stack, allocator_data);
 262                         return NULL;
 263                 }
 264         }
 265         ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, dev_zero, 0);
 266 #endif
 267         if (ptr == MAP_FAILED) {
 268                 SLJIT_FREE(stack, allocator_data);
 269                 return NULL;
 270         }
 271         stack->min_start = (sljit_u8 *)ptr;
 272         stack->end = stack->min_start + max_size;
 273         stack->start = stack->end - start_size;
 274 #endif
 275         stack->top = stack->end;
 276         return stack;
 277 }
 278
 279 #undef PAGE_ALIGN
 280
 281 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_free_stack(struct sljit_stack *stack, void *allocator_data)
 282 {
 283         SLJIT_UNUSED_ARG(allocator_data);
 284 #ifdef _WIN32
 285         VirtualFree((void*)stack->min_start, 0, MEM_RELEASE);
 286 #else
 287         munmap((void*)stack->min_start, stack->end - stack->min_start);
 288 #endif
 289         SLJIT_FREE(stack, allocator_data);
 290 }
 291
 292 SLJIT_API_FUNC_ATTRIBUTE sljit_u8 *SLJIT_FUNC sljit_stack_resize(struct sljit_stack *stack, sljit_u8 *new_start)
 293 {
 294         sljit_uw aligned_old_start;
 295         sljit_uw aligned_new_start;
 296
 297         if ((new_start < stack->min_start) || (new_start >= stack->end))
 298                 return NULL;
 299
 300 #ifdef _WIN32
 301         aligned_new_start = (sljit_uw)new_start & ~sljit_page_align;
 302         aligned_old_start = ((sljit_uw)stack->start) & ~sljit_page_align;
 303         if (aligned_new_start != aligned_old_start) {
 304                 if (aligned_new_start < aligned_old_start) {
 305                         if (!VirtualAlloc((void*)aligned_new_start, aligned_old_start - aligned_new_start, MEM_COMMIT, PAGE_READWRITE))
 306                                 return NULL;
 307                 }
 308                 else {
 309                         if (!VirtualFree((void*)aligned_old_start, aligned_new_start - aligned_old_start, MEM_DECOMMIT))
 310                                 return NULL;
 311                 }
 312         }
 313 #else
 314         if (stack->start < new_start) {
 315                 aligned_new_start = (sljit_uw)new_start & ~sljit_page_align;
 316                 aligned_old_start = ((sljit_uw)stack->start) & ~sljit_page_align;
 317                 /* If madvise is available, we release the unnecessary space. */
 318 #if defined(MADV_DONTNEED)
 319                 if (aligned_new_start > aligned_old_start)
 320                         madvise((void*)aligned_old_start, aligned_new_start - aligned_old_start, MADV_DONTNEED);
 321 #elif defined(POSIX_MADV_DONTNEED)
 322                 if (aligned_new_start > aligned_old_start)
 323                         posix_madvise((void*)aligned_old_start, aligned_new_start - aligned_old_start, POSIX_MADV_DONTNEED);
 324 #endif
 325         }
 326 #endif
 327         stack->start = new_start;
 328         return new_start;
 329 }
 330
 331 #endif /* SLJIT_UTIL_STACK */
 332
 333 #endif