/*

   +----------------------------------------------------------------------+

   | Zend Engine                                                          |

   +----------------------------------------------------------------------+

   | Copyright © Zend Technologies Ltd., a subsidiary company of          |

   |     Perforce Software, Inc., and Contributors.                       |

   +----------------------------------------------------------------------+

   | This source file is subject to the Modified BSD License that is      |

   | bundled with this package in the file LICENSE, and is available      |

   | through the World Wide Web at <https://www.php.net/license/>.        |

   |                                                                      |

   | SPDX-License-Identifier: BSD-3-Clause                                |

   +----------------------------------------------------------------------+

   | Authors: Andi Gutmans <andi@php.net>                                 |

   |          Marcus Boerger <helly@php.net>                              |

   |          Sterling Hughes <sterling@php.net>                          |

   |          Zeev Suraski <zeev@php.net>                                 |

   +----------------------------------------------------------------------+

*/

#include "zend.h"

#include "zend_API.h"

#include "zend_builtin_functions.h"

#include "zend_interfaces.h"

#include "zend_exceptions.h"

#include "zend_vm.h"

#include "zend_dtrace.h"

#include "zend_smart_str.h"

#include "zend_exceptions_arginfo.h"

#include "zend_observer.h"

#define ZEND_EXCEPTION_MESSAGE_OFF 0

#define ZEND_EXCEPTION_CODE_OFF 2

#define ZEND_EXCEPTION_FILE_OFF 3

#define ZEND_EXCEPTION_LINE_OFF 4

#define ZEND_EXCEPTION_TRACE_OFF 5

#define ZEND_EXCEPTION_PREVIOUS_OFF 6

ZEND_API zend_class_entry *zend_ce_throwable;

ZEND_API zend_class_entry *zend_ce_exception;

ZEND_API zend_class_entry *zend_ce_error_exception;

ZEND_API zend_class_entry *zend_ce_error;

ZEND_API zend_class_entry *zend_ce_compile_error;

ZEND_API zend_class_entry *zend_ce_parse_error;

ZEND_API zend_class_entry *zend_ce_type_error;

ZEND_API zend_class_entry *zend_ce_argument_count_error;

ZEND_API zend_class_entry *zend_ce_value_error;

ZEND_API zend_class_entry *zend_ce_arithmetic_error;

ZEND_API zend_class_entry *zend_ce_division_by_zero_error;

ZEND_API zend_class_entry *zend_ce_unhandled_match_error;

ZEND_API zend_class_entry *zend_ce_request_parse_body_exception;

/* Internal pseudo-exception that is not exposed to userland. Throwing this exception *does not* execute finally blocks. */

static zend_class_entry zend_ce_unwind_exit;

/* Internal pseudo-exception that is not exposed to userland. Throwing this exception *does* execute finally blocks. */

static zend_class_entry zend_ce_graceful_exit;

ZEND_API void (*zend_throw_exception_hook)(zend_object *ex);

static zend_object_handlers default_exception_handlers;

/* {{{ zend_implement_throwable */

static int zend_implement_throwable(zend_class_entry *interface, zend_class_entry *class_type)

{

  /* zend_ce_exception and zend_ce_error may not be initialized yet when this is called (e.g when

   * implementing Throwable for Exception itself). Perform a manual inheritance check. */

  const zend_class_entry *root = class_type;

  while (root->parent) {

    root = root->parent;

  }

  if (zend_string_equals_literal(root->name, "Exception")

      || zend_string_equals_literal(root->name, "Error")) {

    return SUCCESS;

  }

  bool can_extend = (class_type->ce_flags & ZEND_ACC_ENUM) == 0;

  zend_error_noreturn(E_ERROR,

    can_extend

      ? "%s %s cannot implement interface %s, extend Exception or Error instead"

      : "%s %s cannot implement interface %s",

    zend_get_object_type_uc(class_type),

    ZSTR_VAL(class_type->name),

    ZSTR_VAL(interface->name));

  return FAILURE;

}

/* }}} */

static inline zend_class_entry *i_get_exception_base(const zend_object *object) /* {{{ */

{

  return instanceof_function(object->ce, zend_ce_exception) ? zend_ce_exception : zend_ce_error;

}

/* }}} */

ZEND_API zend_class_entry *zend_get_exception_base(const zend_object *object) /* {{{ */

{

  return i_get_exception_base(object);

}

/* }}} */

void zend_exception_set_previous(zend_object *exception, zend_object *add_previous) /* {{{ */

{

  zval *previous, *ancestor, *ex;

  zval  pv, zv, rv;

  zend_class_entry *base_ce;

  if (!exception || !add_previous) {

    return;

  }

  if (exception == add_previous || zend_is_unwind_exit(add_previous) || zend_is_graceful_exit(add_previous)) {

    OBJ_RELEASE(add_previous);

    return;

  }

  ZEND_ASSERT(instanceof_function(add_previous->ce, zend_ce_throwable)

    && "Previous exception must implement Throwable");

  ZVAL_OBJ(&pv, add_previous);

  ZVAL_OBJ(&zv, exception);

  ex = &zv;

  do {

    ancestor = zend_read_property_ex(i_get_exception_base(add_previous), add_previous, ZSTR_KNOWN(ZEND_STR_PREVIOUS), 1, &rv);

    ZVAL_DEREF(ancestor);

    while (Z_TYPE_P(ancestor) == IS_OBJECT) {

      if (Z_OBJ_P(ancestor) == Z_OBJ_P(ex)) {

        OBJ_RELEASE(add_previous);

        return;

      }

      ancestor = zend_read_property_ex(i_get_exception_base(Z_OBJ_P(ancestor)), Z_OBJ_P(ancestor), ZSTR_KNOWN(ZEND_STR_PREVIOUS), 1, &rv);

      ZVAL_DEREF(ancestor);

    }

    base_ce = i_get_exception_base(Z_OBJ_P(ex));

    previous = zend_read_property_ex(base_ce, Z_OBJ_P(ex), ZSTR_KNOWN(ZEND_STR_PREVIOUS), 1, &rv);

    ZVAL_DEREF(previous);

    if (Z_TYPE_P(previous) == IS_NULL) {

      zend_update_property_ex(base_ce, Z_OBJ_P(ex), ZSTR_KNOWN(ZEND_STR_PREVIOUS), &pv);

      GC_DELREF(add_previous);

      return;

    }

    ex = previous;

  } while (Z_OBJ_P(ex) != add_previous);

}

/* }}} */

static zend_always_inline bool is_handle_exception_set(void) {

  zend_execute_data *execute_data = EG(current_execute_data);

  return !execute_data

    || !execute_data->func

    || !ZEND_USER_CODE(execute_data->func->common.type)

    || execute_data->opline->opcode == ZEND_HANDLE_EXCEPTION;

}

ZEND_API ZEND_COLD void zend_throw_exception_internal(zend_object *exception) /* {{{ */

{

#ifdef HAVE_DTRACE

  if (DTRACE_EXCEPTION_THROWN_ENABLED()) {

    if (exception != NULL) {

      DTRACE_EXCEPTION_THROWN(ZSTR_VAL(exception->ce->name));

    } else {

      DTRACE_EXCEPTION_THROWN(NULL);

    }

  }

#endif /* HAVE_DTRACE */

  if (exception != NULL) {

    const zend_object *previous = EG(exception);

    if (previous && zend_is_unwind_exit(previous)) {

      /* Don't replace unwinding exception with different exception. */

      OBJ_RELEASE(exception);

      return;

    }

    zend_exception_set_previous(exception, EG(exception));

    EG(exception) = exception;

    if (previous) {

      return;

    }

  }

  if (!EG(current_execute_data)) {

    if (exception && (exception->ce == zend_ce_parse_error || exception->ce == zend_ce_compile_error)) {

      return;

    }

    if (EG(exception)) {

      if (Z_TYPE(EG(user_exception_handler)) != IS_UNDEF

       && !zend_is_unwind_exit(EG(exception))

       && !zend_is_graceful_exit(EG(exception))) {

        zend_user_exception_handler();

        if (EG(exception)) {

          zend_exception_error(EG(exception), E_ERROR);

        }

        return;

      } else {

        zend_exception_error(EG(exception), E_ERROR);

      }

      zend_bailout();

    }

    zend_error_noreturn(E_CORE_ERROR, "Exception thrown without a stack frame");

  }

  if (zend_throw_exception_hook) {

    zend_throw_exception_hook(exception);

  }

  if (is_handle_exception_set()) {

    /* no need to rethrow the exception */

    return;

  }

  EG(opline_before_exception) = EG(current_execute_data)->opline;

  EG(current_execute_data)->opline = EG(exception_op);

}

/* }}} */

ZEND_API void zend_clear_exception(void) /* {{{ */

{

  zend_object *exception;

  if (!EG(exception)) {

    return;

  }

  /* exception may have destructor */

  exception = EG(exception);

  EG(exception) = NULL;

  OBJ_RELEASE(exception);

  if (EG(current_execute_data)) {

    EG(current_execute_data)->opline = EG(opline_before_exception);

  }

#if ZEND_DEBUG

  EG(opline_before_exception) = NULL;

#endif

}

/* }}} */

/* Same as writing to OBJ_PROP_NUM() when there are no hooks,

 * but checks the offset is correct when Zend is built in debug mode.

 * This is faster than going through the regular property write routine when the offset is known at compile time. */

static void zend_update_property_num_checked(zend_class_entry *scope, zend_object *object, uint32_t prop_num, zend_string *member, zval *value)

{

  if (UNEXPECTED(object->ce->num_hooked_props > 0)) {

    /* Property may have been overridden with a hook. */

    zend_update_property_ex(scope != NULL ? scope : object->ce, object, member, value);

    zval_ptr_dtor(value);

    return;

  }

#if ZEND_DEBUG

  const zend_class_entry *old_scope = EG(fake_scope);

  EG(fake_scope) = i_get_exception_base(object);

  const zend_property_info *prop_info = zend_get_property_info(object->ce, member, true);

  ZEND_ASSERT(OBJ_PROP_TO_NUM(prop_info->offset) == prop_num);

  EG(fake_scope) = old_scope;

#endif

  zval *zv = OBJ_PROP_NUM(object, prop_num);

  zval_ptr_safe_dtor(zv);

  ZVAL_COPY_VALUE(zv, value);

}

static zend_object *zend_default_exception_new(zend_class_entry *class_type) /* {{{ */

{

  zval tmp;

  zval trace;

  zend_string *filename;

  zend_object *object = zend_objects_new(class_type);

  object_properties_init(object, class_type);

  if (EG(current_execute_data)) {

    zend_fetch_debug_backtrace(&trace,

      0,

      EG(exception_ignore_args) ? DEBUG_BACKTRACE_IGNORE_ARGS : 0, 0);

  } else {

    ZVAL_EMPTY_ARRAY(&trace);

  }

  zend_update_property_num_checked(i_get_exception_base(object), object, ZEND_EXCEPTION_TRACE_OFF, ZSTR_KNOWN(ZEND_STR_TRACE), &trace);

  if (EXPECTED((class_type != zend_ce_parse_error && class_type != zend_ce_compile_error)

      || !(filename = zend_get_compiled_filename()))) {

    ZVAL_STRING(&tmp, zend_get_executed_filename());

    zend_update_property_num_checked(NULL, object, ZEND_EXCEPTION_FILE_OFF, ZSTR_KNOWN(ZEND_STR_FILE), &tmp);

    ZVAL_LONG(&tmp, zend_get_executed_lineno());

    zend_update_property_num_checked(NULL, object, ZEND_EXCEPTION_LINE_OFF, ZSTR_KNOWN(ZEND_STR_LINE), &tmp);

  } else {

    ZVAL_STR_COPY(&tmp, filename);

    zend_update_property_num_checked(NULL, object, ZEND_EXCEPTION_FILE_OFF, ZSTR_KNOWN(ZEND_STR_FILE), &tmp);

    ZVAL_LONG(&tmp, zend_get_compiled_lineno());

    zend_update_property_num_checked(NULL, object, ZEND_EXCEPTION_LINE_OFF, ZSTR_KNOWN(ZEND_STR_LINE), &tmp);

  }

  return object;

}

/* }}} */

/* {{{ Clone the exception object */

ZEND_COLD ZEND_METHOD(Exception, __clone)

{

  /* __clone() is private but this is reachable with reflection */

  zend_throw_exception(NULL, "Cannot clone object using __clone()", 0);

}

/* }}} */

ZEND_API zend_result zend_update_exception_properties(INTERNAL_FUNCTION_PARAMETERS, zend_string *message, zend_long code, zval *previous)

{

  zval tmp, *object = ZEND_THIS;

  if (message) {

    ZVAL_STR_COPY(&tmp, message);

    zend_update_property_num_checked(NULL, Z_OBJ_P(object), ZEND_EXCEPTION_MESSAGE_OFF, ZSTR_KNOWN(ZEND_STR_MESSAGE), &tmp);

    if (UNEXPECTED(EG(exception))) {

      return FAILURE;

    }

  }

  if (code) {

    ZVAL_LONG(&tmp, code);

    zend_update_property_num_checked(NULL, Z_OBJ_P(object), ZEND_EXCEPTION_CODE_OFF, ZSTR_KNOWN(ZEND_STR_CODE), &tmp);

    if (UNEXPECTED(EG(exception))) {

      return FAILURE;

    }

  }

  if (previous) {

    Z_ADDREF_P(previous);

    zend_update_property_num_checked(zend_ce_exception, Z_OBJ_P(object), ZEND_EXCEPTION_PREVIOUS_OFF, ZSTR_KNOWN(ZEND_STR_PREVIOUS), previous);

    if (UNEXPECTED(EG(exception))) {

      return FAILURE;

    }

  }

  return SUCCESS;

}

/* {{{ Exception constructor */

ZEND_METHOD(Exception, __construct)

{

  zend_string *message = NULL;

  zend_long   code = 0;

  zval *previous = NULL;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "|SlO!", &message, &code, &previous, zend_ce_throwable) == FAILURE) {

    RETURN_THROWS();

  }

  if (zend_update_exception_properties(INTERNAL_FUNCTION_PARAM_PASSTHRU, message, code, previous) == FAILURE) {

    RETURN_THROWS();

  }

}

/* }}} */

/* {{{ Exception unserialize checks */

#define CHECK_EXC_TYPE(id, type) \

  pvalue = zend_read_property_ex(i_get_exception_base(Z_OBJ_P(object)), Z_OBJ_P(object), ZSTR_KNOWN(id), 1, &value); \

  if (Z_TYPE_P(pvalue) != IS_NULL && Z_TYPE_P(pvalue) != type) { \

    zend_unset_property(i_get_exception_base(Z_OBJ_P(object)), Z_OBJ_P(object), ZSTR_VAL(ZSTR_KNOWN(id)), ZSTR_LEN(ZSTR_KNOWN(id))); \

  }

ZEND_METHOD(Exception, __wakeup)

{

  ZEND_PARSE_PARAMETERS_NONE();

  zval value, *pvalue;

  zval *object = ZEND_THIS;

  CHECK_EXC_TYPE(ZEND_STR_MESSAGE, IS_STRING);

  CHECK_EXC_TYPE(ZEND_STR_CODE,    IS_LONG);

  /* The type of all other properties is enforced through typed properties. */

}

/* }}} */

/* {{{ ErrorException constructor */

ZEND_METHOD(ErrorException, __construct)

{

  zend_string *message = NULL, *filename = NULL;

  zend_long   code = 0, severity = E_ERROR, lineno;

  bool lineno_is_null = true;

  zval   tmp, *object, *previous = NULL;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "|SllS!l!O!", &message, &code, &severity, &filename, &lineno, &lineno_is_null, &previous, zend_ce_throwable) == FAILURE) {

    RETURN_THROWS();

  }

  object = ZEND_THIS;

  if (zend_update_exception_properties(INTERNAL_FUNCTION_PARAM_PASSTHRU, message, code, previous) == FAILURE) {

    RETURN_THROWS();

  }

  ZVAL_LONG(&tmp, severity);

  zend_update_property_ex(zend_ce_exception, Z_OBJ_P(object), ZSTR_KNOWN(ZEND_STR_SEVERITY), &tmp);

  if (UNEXPECTED(EG(exception))) {

    RETURN_THROWS();

  }

  if (filename) {

    ZVAL_STR_COPY(&tmp, filename);

    zend_update_property_num_checked(NULL, Z_OBJ_P(object), ZEND_EXCEPTION_FILE_OFF, ZSTR_KNOWN(ZEND_STR_FILE), &tmp);

    if (UNEXPECTED(EG(exception))) {

      RETURN_THROWS();

    }

  }

  if (!lineno_is_null) {

    ZVAL_LONG(&tmp, lineno);

    zend_update_property_num_checked(NULL, Z_OBJ_P(object), ZEND_EXCEPTION_LINE_OFF, ZSTR_KNOWN(ZEND_STR_LINE), &tmp);

    if (UNEXPECTED(EG(exception))) {

      RETURN_THROWS();

    }

  } else if (filename) {

    ZVAL_LONG(&tmp, 0);

    zend_update_property_num_checked(NULL, Z_OBJ_P(object), ZEND_EXCEPTION_LINE_OFF, ZSTR_KNOWN(ZEND_STR_LINE), &tmp);

    if (UNEXPECTED(EG(exception))) {

      RETURN_THROWS();

    }

  }

}

/* }}} */

#define GET_PROPERTY(object, id) \

  zend_read_property_ex(i_get_exception_base(Z_OBJ_P(object)), Z_OBJ_P(object), ZSTR_KNOWN(id), 0, &rv)

#define GET_PROPERTY_SILENT(object, id) \

  zend_read_property_ex(i_get_exception_base(Z_OBJ_P(object)), Z_OBJ_P(object), ZSTR_KNOWN(id), 1, &rv)

/* {{{ Get the file in which the exception occurred */

ZEND_METHOD(Exception, getFile)

{

  zval *prop, rv;

  ZEND_PARSE_PARAMETERS_NONE();

  prop = GET_PROPERTY(ZEND_THIS, ZEND_STR_FILE);

  RETURN_STR(zval_get_string(prop));

}

/* }}} */

/* {{{ Get the line in which the exception occurred */

ZEND_METHOD(Exception, getLine)

{

  zval *prop, rv;

  ZEND_PARSE_PARAMETERS_NONE();

  prop = GET_PROPERTY(ZEND_THIS, ZEND_STR_LINE);

  RETURN_LONG(zval_get_long(prop));

}

/* }}} */

/* {{{ Get the exception message */

ZEND_METHOD(Exception, getMessage)

{

  zval *prop, rv;

  ZEND_PARSE_PARAMETERS_NONE();

  prop = GET_PROPERTY(ZEND_THIS, ZEND_STR_MESSAGE);

  RETURN_STR(zval_get_string(prop));

}

/* }}} */

/* {{{ Get the exception code */

ZEND_METHOD(Exception, getCode)

{

  zval *prop, rv;

  ZEND_PARSE_PARAMETERS_NONE();

  prop = GET_PROPERTY(ZEND_THIS, ZEND_STR_CODE);

  ZVAL_DEREF(prop);

  ZVAL_COPY(return_value, prop);

}

/* }}} */

/* {{{ Get the stack trace for the location in which the exception occurred */

ZEND_METHOD(Exception, getTrace)

{

  zval *prop, rv;

  ZEND_PARSE_PARAMETERS_NONE();

  prop = GET_PROPERTY(ZEND_THIS, ZEND_STR_TRACE);

  ZVAL_DEREF(prop);

  ZVAL_COPY(return_value, prop);

}

/* }}} */

/* {{{ Get the exception severity */

ZEND_METHOD(ErrorException, getSeverity)

{

  zval *prop, rv;

  ZEND_PARSE_PARAMETERS_NONE();

  prop = GET_PROPERTY(ZEND_THIS, ZEND_STR_SEVERITY);

  ZVAL_DEREF(prop);

  ZVAL_COPY(return_value, prop);

}

/* }}} */

#define TRACE_APPEND_KEY(key) do {                                          \

    tmp = zend_hash_find(ht, key);                                      \

    if (tmp) {                                                          \

      if (UNEXPECTED(Z_TYPE_P(tmp) != IS_STRING)) {                   \

        zend_error(E_WARNING, "Value for %s is not a string",       \

          ZSTR_VAL(key));                                         \

        smart_str_appends(str, "[unknown]");                        \

      } else {                                                        \

        smart_str_append(str, Z_STR_P(tmp));                        \

      }                                                               \

    } \

  } while (0)

static void build_trace_args(zval *arg, smart_str *str) /* {{{ */

{

  /* the trivial way would be to do

   * convert_to_string(arg);

   * append it and kill the now tmp arg.

   * but that could cause some E_NOTICE and also damn long lines.

   */

  ZVAL_DEREF(arg);

  if (smart_str_append_zval(str, arg, EG(exception_string_param_max_len)) != SUCCESS) {

    switch (Z_TYPE_P(arg)) {

      case IS_RESOURCE:

        smart_str_appends(str, "Resource id #");

        smart_str_append_long(str, Z_RES_HANDLE_P(arg));

        break;

      case IS_ARRAY:

        smart_str_appends(str, "Array");

        break;

      case IS_OBJECT: {

        zend_string *class_name = Z_OBJ_HANDLER_P(arg, get_class_name)(Z_OBJ_P(arg));

        smart_str_appends(str, "Object(");

        /* cut off on NULL byte ... class@anonymous */

        smart_str_appends(str, ZSTR_VAL(class_name));

        smart_str_appends(str, ")");

        zend_string_release_ex(class_name, 0);

        break;

      }

    }

  }

}

/* }}} */

static void build_trace_args_list(zval *tmp, smart_str *str) /* {{{ */

{

  if (UNEXPECTED(Z_TYPE_P(tmp) != IS_ARRAY)) {

    /* only happens w/ reflection abuse (Zend/tests/bug63762.phpt) */

    zend_error(E_WARNING, "args element is not an array");

    return;

  }

  bool first = true;

  ZEND_HASH_FOREACH_STR_KEY_VAL(Z_ARRVAL_P(tmp), zend_string *name, zval *arg) {

    if (!first) {

      smart_str_appends(str, ", ");

    }

    first = false;

    if (name) {

      smart_str_append(str, name);

      smart_str_appends(str, ": ");

    }

    build_trace_args(arg, str);

  } ZEND_HASH_FOREACH_END();

}

/* }}} */

static void build_trace_string(smart_str *str, const HashTable *ht, uint32_t num) /* {{{ */

{

  zval *file, *tmp;

  smart_str_appendc(str, '#');

  smart_str_append_long(str, num);

  smart_str_appendc(str, ' ');

  file = zend_hash_find_known_hash(ht, ZSTR_KNOWN(ZEND_STR_FILE));

  if (file) {

    if (UNEXPECTED(Z_TYPE_P(file) != IS_STRING)) {

      zend_error(E_WARNING, "File name is not a string");

      smart_str_appends(str, "[unknown file]: ");

    } else{

      zend_long line = 0;

      tmp = zend_hash_find_known_hash(ht, ZSTR_KNOWN(ZEND_STR_LINE));

      if (tmp) {

        if (EXPECTED(Z_TYPE_P(tmp) == IS_LONG)) {

          line = Z_LVAL_P(tmp);

        } else {

          zend_error(E_WARNING, "Line is not an int");

        }

      }

      smart_str_append(str, Z_STR_P(file));

      smart_str_appendc(str, '(');

      smart_str_append_long(str, line);

      smart_str_appends(str, "): ");

    }

  } else {

    smart_str_appends(str, "[internal function]: ");

  }

  const zval *class_name = zend_hash_find(ht, ZSTR_KNOWN(ZEND_STR_CLASS));

  if (class_name) {

    if (UNEXPECTED(Z_TYPE_P(class_name) != IS_STRING)) {

      zend_error(E_WARNING, "Value for class is not a string");

      smart_str_appends(str, "[unknown]");

    } else {

      /* cut off on NULL byte ... class@anonymous */

      smart_str_appends(str, Z_STRVAL_P(class_name));

    }

  }

  TRACE_APPEND_KEY(ZSTR_KNOWN(ZEND_STR_TYPE));

  TRACE_APPEND_KEY(ZSTR_KNOWN(ZEND_STR_FUNCTION));

  smart_str_appendc(str, '(');

  tmp = zend_hash_find_known_hash(ht, ZSTR_KNOWN(ZEND_STR_ARGS));

  if (tmp) {

    build_trace_args_list(tmp, str);

  }

  smart_str_appends(str, ")\n");

}

/* }}} */

/* {{{ Gets the function arguments printed as a string from a backtrace frame. */

ZEND_API zend_string *zend_trace_function_args_to_string(const HashTable *frame) {

  smart_str str = {0};

  zval *tmp = zend_hash_find_known_hash(frame, ZSTR_KNOWN(ZEND_STR_ARGS));

  if (tmp) {

    build_trace_args_list(tmp, &str);

  }

  return smart_str_extract(&str);

}

/* }}} */

/* {{{ Gets the currently executing function's arguments as a string. Used by php_verror. */

ZEND_API zend_string *zend_trace_current_function_args_string(void) {

  zend_string *dynamic_params = NULL;

  /* get a backtrace to snarf function args */

  zval backtrace;

  zend_fetch_debug_backtrace(&backtrace, /* skip_last */ 0, /* options */ 0, /* limit */ 1);

  /* can fail esp if low memory condition */

  if (Z_TYPE(backtrace) == IS_ARRAY) {

    zval *first_frame = zend_hash_index_find(Z_ARRVAL(backtrace), 0);

    if (first_frame) {

      dynamic_params = zend_trace_function_args_to_string(Z_ARRVAL_P(first_frame));

    }

  }

  zval_ptr_dtor(&backtrace);

  return dynamic_params;

}

/* }}} */

ZEND_API zend_string *zend_trace_to_string(const HashTable *trace, bool include_main) {

  zend_ulong index;

  zval *frame;

  uint32_t num = 0;

  smart_str str = {0};

  ZEND_HASH_FOREACH_NUM_KEY_VAL(trace, index, frame) {

    if (UNEXPECTED(Z_TYPE_P(frame) != IS_ARRAY)) {

      zend_error(E_WARNING, "Expected array for frame " ZEND_ULONG_FMT, index);

      continue;

    }

    build_trace_string(&str, Z_ARRVAL_P(frame), num++);

  } ZEND_HASH_FOREACH_END();

  if (include_main) {

    smart_str_appendc(&str, '#');

    smart_str_append_long(&str, num);

    smart_str_appends(&str, " {main}");

  }

  smart_str_0(&str);

  return str.s ? str.s : ZSTR_EMPTY_ALLOC();

}

/* {{{ Obtain the backtrace for the exception as a string (instead of an array) */

ZEND_METHOD(Exception, getTraceAsString)

{

  ZEND_PARSE_PARAMETERS_NONE();

  zval *object = ZEND_THIS;

  zend_class_entry *base_ce = i_get_exception_base(Z_OBJ_P(object));

  zval rv;

  const zval *trace = zend_read_property_ex(base_ce, Z_OBJ_P(object), ZSTR_KNOWN(ZEND_STR_TRACE), 1, &rv);

  if (EG(exception)) {

    RETURN_THROWS();

  }

  ZVAL_DEREF(trace);

  /* Type should be guaranteed by property type. */

  ZEND_ASSERT(Z_TYPE_P(trace) == IS_ARRAY);

  RETURN_NEW_STR(zend_trace_to_string(Z_ARRVAL_P(trace), /* include_main */ true));

}

/* }}} */

/* {{{ Return previous Throwable or NULL. */

ZEND_METHOD(Exception, getPrevious)

{

  zval rv;

  ZEND_PARSE_PARAMETERS_NONE();

  ZVAL_COPY_DEREF(return_value, GET_PROPERTY_SILENT(ZEND_THIS, ZEND_STR_PREVIOUS));

} /* }}} */

/* {{{ Obtain the string representation of the Exception object */

ZEND_METHOD(Exception, __toString)

{

  zval trace, *exception;

  zend_class_entry *base_ce;

  zend_string *str;

  zval rv, tmp;

  ZEND_PARSE_PARAMETERS_NONE();

  str = ZSTR_EMPTY_ALLOC();

  exception = ZEND_THIS;

  base_ce = i_get_exception_base(Z_OBJ_P(exception));

  /* As getTraceAsString method is final we can grab it once */

  zend_function *getTraceAsString = zend_hash_str_find_ptr(&base_ce->function_table, ZEND_STRL("gettraceasstring"));

  ZEND_ASSERT(getTraceAsString && "Method getTraceAsString must exist");

  zend_fcall_info fci;

  fci.size = sizeof(fci);

  ZVAL_UNDEF(&fci.function_name);

  fci.retval = &trace;

  fci.param_count = 0;

  fci.params = NULL;

  fci.object = NULL;

  fci.named_params = NULL;

  zend_fcall_info_cache fcc;

  fcc.function_handler = getTraceAsString;

  fcc.called_scope = base_ce;

  fcc.closure = NULL;

  while (exception && Z_TYPE_P(exception) == IS_OBJECT && instanceof_function(Z_OBJCE_P(exception), zend_ce_throwable)) {

    zend_string *prev_str = str;

    zend_string *message = zval_get_string(GET_PROPERTY(exception, ZEND_STR_MESSAGE));

    zend_string *file = zval_get_string(GET_PROPERTY(exception, ZEND_STR_FILE));

    zend_long line = zval_get_long(GET_PROPERTY(exception, ZEND_STR_LINE));

    fcc.object = Z_OBJ_P(exception);

    fcc.calling_scope = Z_OBJCE_P(exception);

    zend_call_function(&fci, &fcc);

    if (Z_TYPE(trace) != IS_STRING) {

      zval_ptr_dtor(&trace);

      ZVAL_UNDEF(&trace);

    }

    if ((Z_OBJCE_P(exception) == zend_ce_type_error || Z_OBJCE_P(exception) == zend_ce_argument_count_error) && strstr(ZSTR_VAL(message), ", called in ")) {

      zend_string *real_message = zend_strpprintf_unchecked(0, "%S and defined", message);

      zend_string_release_ex(message, 0);

      message = real_message;

    }

    zend_string *tmp_trace = (Z_TYPE(trace) == IS_STRING && Z_STRLEN(trace))

      ? zend_string_copy(Z_STR(trace))

      : ZSTR_INIT_LITERAL("#0 {main}\n", false);

    zend_string *name = Z_OBJCE_P(exception)->name;

    if (ZSTR_LEN(message) > 0) {

      zval message_zv;

      ZVAL_STR(&message_zv, message);

      str = zend_strpprintf_unchecked(0, "%S: %S in %S:" ZEND_LONG_FMT "\nStack trace:\n%S%s%S",

        name, message, file, line,

        tmp_trace, ZSTR_LEN(prev_str) ? "\n\nNext " : "", prev_str);

    } else {

      str = zend_strpprintf_unchecked(0, "%S in %S:" ZEND_LONG_FMT "\nStack trace:\n%S%s%S",

        name, file, line,

        tmp_trace, ZSTR_LEN(prev_str) ? "\n\nNext " : "", prev_str);

    }

    zend_string_release_ex(tmp_trace, false);

    zend_string_release_ex(prev_str, 0);

    zend_string_release_ex(message, 0);

    zend_string_release_ex(file, 0);

    zval_ptr_dtor(&trace);

    Z_PROTECT_RECURSION_P(exception);

    exception = GET_PROPERTY(exception, ZEND_STR_PREVIOUS);

    ZVAL_DEREF(exception);

    if (Z_TYPE_P(exception) == IS_OBJECT && Z_IS_RECURSIVE_P(exception)) {

      break;

    }

  }

  exception = ZEND_THIS;

  /* Reset apply counts */

  zend_class_entry *previous_base_ce;

  while (Z_TYPE_P(exception) == IS_OBJECT && (previous_base_ce = i_get_exception_base(Z_OBJ_P(exception))) && instanceof_function(Z_OBJCE_P(exception), previous_base_ce)) {

    if (Z_IS_RECURSIVE_P(exception)) {

      Z_UNPROTECT_RECURSION_P(exception);

    } else {

      break;

    }

    exception = GET_PROPERTY(exception, ZEND_STR_PREVIOUS);

    ZVAL_DEREF(exception);

  }

  /* We store the result in the private property string so we can access

   * the result in uncaught exception handlers without memleaks. */

  ZVAL_STR(&tmp, str);

  zend_update_property_ex(base_ce, Z_OBJ_P(ZEND_THIS), ZSTR_KNOWN(ZEND_STR_STRING), &tmp);

  RETURN_STR(str);

}

/* }}} */

static void zend_init_exception_class_entry(zend_class_entry *ce) {

  ce->create_object = zend_default_exception_new;

  ce->default_object_handlers = &default_exception_handlers;

}

void zend_register_default_exception(void) /* {{{ */

{

  zend_ce_throwable = register_class_Throwable(zend_ce_stringable);

  zend_ce_throwable->interface_gets_implemented = zend_implement_throwable;

  memcpy(&default_exception_handlers, &std_object_handlers, sizeof(zend_object_handlers));

  default_exception_handlers.clone_obj = NULL;

  zend_ce_exception = register_class_Exception(zend_ce_throwable);

  zend_init_exception_class_entry(zend_ce_exception);

  zend_ce_error_exception = register_class_ErrorException(zend_ce_exception);

  zend_init_exception_class_entry(zend_ce_error_exception);

  zend_ce_error = register_class_Error(zend_ce_throwable);

  zend_init_exception_class_entry(zend_ce_error);

  zend_ce_compile_error = register_class_CompileError(zend_ce_error);

  zend_init_exception_class_entry(zend_ce_compile_error);

  zend_ce_parse_error = register_class_ParseError(zend_ce_compile_error);

  zend_init_exception_class_entry(zend_ce_parse_error);

  zend_ce_type_error = register_class_TypeError(zend_ce_error);

  zend_init_exception_class_entry(zend_ce_type_error);

  zend_ce_argument_count_error = register_class_ArgumentCountError(zend_ce_type_error);

  zend_init_exception_class_entry(zend_ce_argument_count_error);

  zend_ce_value_error = register_class_ValueError(zend_ce_error);

  zend_init_exception_class_entry(zend_ce_value_error);

  zend_ce_arithmetic_error = register_class_ArithmeticError(zend_ce_error);

  zend_init_exception_class_entry(zend_ce_arithmetic_error);

  zend_ce_division_by_zero_error = register_class_DivisionByZeroError(zend_ce_arithmetic_error);

  zend_init_exception_class_entry(zend_ce_division_by_zero_error);

  zend_ce_unhandled_match_error = register_class_UnhandledMatchError(zend_ce_error);

  zend_init_exception_class_entry(zend_ce_unhandled_match_error);

  zend_ce_request_parse_body_exception = register_class_RequestParseBodyException(zend_ce_exception);

  zend_init_exception_class_entry(zend_ce_request_parse_body_exception);