pcre2_jit_match.c

/*************************************************
*      Perl-Compatible Regular Expressions       *
*************************************************/

/* PCRE is a library of functions to support regular expressions whose syntax
and semantics are as close as possible to those of the Perl 5 language.

                       Written by Philip Hazel
     Original API code Copyright (c) 1997-2012 University of Cambridge
          New API code Copyright (c) 2016-2018 University of Cambridge

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    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.

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      this software without specific prior written permission.

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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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-----------------------------------------------------------------------------
*/

#ifndef INCLUDED_FROM_PCRE2_JIT_COMPILE
#error This file must be included from pcre2_jit_compile.c.
#endif

#ifdef SUPPORT_JIT

static SLJIT_NOINLINE int jit_machine_stack_exec(jit_arguments *arguments, jit_function executable_func)
{
sljit_u8 local_space[MACHINE_STACK_SIZE];
struct sljit_stack local_stack;

local_stack.min_start = local_space;
local_stack.start = local_space;
local_stack.end = local_space + MACHINE_STACK_SIZE;
local_stack.top = local_space + MACHINE_STACK_SIZE;
arguments->stack = &local_stack;
return executable_func(arguments);
}

#endif


/*************************************************
*              Do a JIT pattern match            *
*************************************************/

/* This function runs a JIT pattern match.

Arguments:
  code            points to the compiled expression
  subject         points to the subject string
  length          length of subject string (may contain binary zeros)
  start_offset    where to start in the subject string
  options         option bits
  match_data      points to a match_data block
  mcontext        points to a match context
  jit_stack       points to a JIT stack

Returns:          > 0 => success; value is the number of ovector pairs filled
                  = 0 => success, but ovector is not big enough
                   -1 => failed to match (PCRE_ERROR_NOMATCH)
                 < -1 => some kind of unexpected problem
*/

PCRE2_EXP_DEFN int PCRE2_CALL_CONVENTION
pcre2_jit_match(const pcre2_code *code, PCRE2_SPTR subject, PCRE2_SIZE length,
  PCRE2_SIZE start_offset, uint32_t options, pcre2_match_data *match_data,
  pcre2_match_context *mcontext)
{
#ifndef SUPPORT_JIT

(void)code;
(void)subject;
(void)length;
(void)start_offset;
(void)options;
(void)match_data;
(void)mcontext;
return PCRE2_ERROR_JIT_BADOPTION;

#else  /* SUPPORT_JIT */

pcre2_real_code *re = (pcre2_real_code *)code;
executable_functions *functions = (executable_functions *)re->executable_jit;
pcre2_jit_stack *jit_stack;
uint32_t oveccount = match_data->oveccount;
uint32_t max_oveccount;
union {
   void *executable_func;
   jit_function call_executable_func;
} convert_executable_func;
jit_arguments arguments;
int rc;
int index = 0;

if ((options & PCRE2_PARTIAL_HARD) != 0)
  index = 2;
else if ((options & PCRE2_PARTIAL_SOFT) != 0)
  index = 1;

if (functions == NULL || functions->executable_funcs[index] == NULL)
  return PCRE2_ERROR_JIT_BADOPTION;

/* Sanity checks should be handled by pcre_exec. */
arguments.str = subject + start_offset;
arguments.begin = subject;
arguments.end = subject + length;
arguments.match_data = match_data;
arguments.startchar_ptr = subject;
arguments.mark_ptr = NULL;
arguments.options = options;

if (mcontext != NULL)
  {
  arguments.callout = mcontext->callout;
  arguments.callout_data = mcontext->callout_data;
  arguments.offset_limit = mcontext->offset_limit;
  arguments.limit_match = (mcontext->match_limit < re->limit_match)?
    mcontext->match_limit : re->limit_match;
  if (mcontext->jit_callback != NULL)
    jit_stack = mcontext->jit_callback(mcontext->jit_callback_data);
  else
    jit_stack = (pcre2_jit_stack *)mcontext->jit_callback_data;
  }
else
  {
  arguments.callout = NULL;
  arguments.callout_data = NULL;
  arguments.offset_limit = PCRE2_UNSET;
  arguments.limit_match = (MATCH_LIMIT < re->limit_match)?
    MATCH_LIMIT : re->limit_match;
  jit_stack = NULL;
  }


max_oveccount = functions->top_bracket;
if (oveccount > max_oveccount)
  oveccount = max_oveccount;
arguments.oveccount = oveccount << 1;


convert_executable_func.executable_func = functions->executable_funcs[index];
if (jit_stack != NULL)
  {
  arguments.stack = (struct sljit_stack *)(jit_stack->stack);
  rc = convert_executable_func.call_executable_func(&arguments);
  }
else
  rc = jit_machine_stack_exec(&arguments, convert_executable_func.call_executable_func);

if (rc > (int)oveccount)
  rc = 0;
match_data->code = re;
match_data->subject = (rc >= 0 || rc == PCRE2_ERROR_PARTIAL)? subject : NULL;
match_data->rc = rc;
match_data->startchar = arguments.startchar_ptr - subject;
match_data->leftchar = 0;
match_data->rightchar = 0;
match_data->mark = arguments.mark_ptr;
match_data->matchedby = PCRE2_MATCHEDBY_JIT;

return match_data->rc;

#endif  /* SUPPORT_JIT */
}

/* End of pcre2_jit_match.c */